Berry Fruit - Value-Added Products

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Berry

Fruit

Value-Added Products

for Health Promotion

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FOOD SCIENCE

AND TECHNOLOGY

Editorial Advisory Board

Gustavo V. Barbosa-Cánovas Washington State University–Pullman P. Michael Davidson University of Tennessee–Knoxville

Mark Dreher McNeil Nutritionals, New Brunswick, NJ Richard W. Hartel University of Wisconsin–Madison

Lekh R. Juneja Taiyo Kagaku Company, Japan Marcus Karel Massachusetts Institute of Technology Ronald G. Labbe University of Massachusetts–Amherst

Daryl B. Lund University of Wisconsin–Madison David B. Min The Ohio State University Leo M. L. Nollet Hogeschool Gent, Belgium Seppo Salminen University of Turku, Finland

John H. Thorngate III Allied Domecq Technical Services, Napa, CA Pieter Walstra Wageningen University, The Netherlands

John R. Whitaker University of California–Davis Rickey Y. Yada University of Guelph, Canada

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Berry

Fruit

edited by

Yanyun Zhao

Value-Added Products

for Health Promotion

CRC Press is an imprint of the

Taylor & Francis Group, an informa business Boca Raton London New York

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Library of Congress Cataloging-in-Publication Data

Berry fruit : value-added products for health promotion / editor, Yanyun Zhao. p. ; cm. -- (Food science and technology ; 168)

Includes bibliographical references and index. ISBN-13: 978-0-8493-5802-9 (hardcover : alk. paper) ISBN-10: 0-8493-5802-7 (hardcover : alk. paper)

1. Berries. I. Zhao, Yanyun, Dr. II. Title. III. Series: Food science and technology (Taylor & Francis); 168.

[DNLM: 1. Fruit. 2. Food Analysis. 3. Food Handling. 4. Nutritive Value. W1 FO509P v.168 2007 / WB 430 B534 2007]

QP144.F78B47 2007

634’.7--dc22 2007001325

Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com

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Preface

Berries are highly valued fruit crops for their unique flavors, textures, and colors. In recent years, berries have been shown to provide significant health benefits because of their high antioxidant content, vitamins and minerals, fiber, folic acid, etc. In addition to fresh consumption, berry fruits are widely used in beverages, ice cream, yogurt, milkshakes, jams, jellies, smoothies, and many other food products.

This book covers the basic functional chemicals (bioactive compounds), significant health benefits, shelf life, and microbial safety concerns associated with postharvest handling and storage, technologies to develop value-added berry products with high quality, and significant nutraceutical benefits. This book is divided into three parts: bioactive compounds of berry fruit and their health benefits, quality and safety of berry fruit during postharvest handling and storage, and processing technologies for developing value-added berry fruit products.

Each chapter in this book is written by an international expert (or experts), presenting information on the scientific background, research results, and critical reviews of the relevant issue, including a comprehensive list of recently published literature, and case studies, thus providing valuable sources of information for further research and development of berry fruit for the food industry.

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Editor

Dr. Yanyun Zhao received her Ph.D. in food engineering from Louisiana State University, Baton Rouge, Louisiana, in 1993 and is now an associate professor in the Department of Food Science and Technology at Oregon State University, Corvallis, Oregon, with formal responsibilities in extension, research, and teaching. Dr. Zhao’s research efforts are in the area of value-added food products development, with an emphasis on using novel food processing and packaging techniques for developing fruit- and vegetable-based functional foods. Dr. Zhao’s extension activities include providing leadership in identifying educational needs and creating, delivering, and eval-uating educational programs and materials in value-added fruit and vegetable products. Dr. Zhao teaches “Fruit and Vegetable Processing” and “Functional Foods” courses.

Dr. Zhao has published more than 40 journal articles and 8 book chapters, holds 6 patents, and has received more than 10 U.S. Department of Agricul-ture (USDA) competitive grants totaling about $1.5 million. Dr. Zhao serves on the editorial board of the Journal of Food Processing and Preservation, on advisory boards of several industrial organizations, is an expert reviewer for several peer-reviewed journals and USDA competitive research grant pro-grams, and is an active member of the Institute of Food Technologists (IFT).

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Contributors

Dr. Bernadine C. Strik

Department of Horticulture Oregon State University Corvallis, Oregon

Dr. Stephen T. Talcott

Department of Nutrition and Food Science

Texas A&M University College Station, Texas

Dr. Luke R. Howard

Department of Food Science University of Arkansas Fayetteville, Arkansas

Dr. Tiffany J. Hager

Department of Food Science University of Arkansas Fayetteville, Arkansas

Dr. M. Monica Giusti

Food Science and Technology The Ohio State University Columbus, Ohio

Dr. Pu Jing

Food Science and Technology The Ohio State University Columbus, Ohio

Dr. Shiow Y. Wang

Fruit Laboratory, Beltsville Agricultural Research Center, U.S. Department of Agriculture Beltsville, Maryland

Dr. Rui Hai Liu

Department of Food Science Cornell University

Ithaca, New York

Dr. Elizabeth Mitcham

Department of Pomology University of California Davis, California

Dr. Mark A. Daeschel

Department of Food Science and Technology

Oregon State University Corvallis, Oregon

Pathima Udompijitkul

Department of Food Science and Technology

Oregon State University Corvallis, Oregon

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Dr. Cynthia Bower

U.S. Department of Agriculture Agricultural Research Service Subarctic Agricultural Research

Unit, University of Alaska– Fairbanks

Fairbanks, Alaska

Dr. Fernando E. Figuerola

Tecnología de Alimentos

Instituto de Ciencia y Tecnología de los Alimentos (ICYTAL) Universidad Austral de Chile Valdivia, Chile

Dr. Hosahalli Ramaswamy

Department of Food Science and Agricultural Chemistry

McGill University, Ste. Anne de Bellevue

Quebec, Canada

Dr. Yang Meng

Department of Food Science and Agricultural Chemistry

McGill University, Ste. Anne de Bellevue

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Part I

Bioactive compounds

of berry fruits

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3

chapter 1 Berry crops: Worldwide area

and production systems

Bernadine C. Strik

1.1 Introduction

In 2005, there were more than 1.8 million acres of berry crops worldwide pro-ducing 6.3 million tons of fruit. The major berry crops grown, excluding grapes, are strawberries, black currants, blueberries, red raspberries, gooseberries, cran-berries, and blackberries. Other minor berry crops are also grown commercially, including black raspberries, hardy kiwifruit, chokeberries, elderberries, saska-toons, and lingonberries. In addition, harvesting of some berries from the wild, including blueberries, blackberries, raspberries, cranberries, and lingonberries, contributes significantly to the worldwide availability of berry fruit.

Berry crops are grown and sold via one of three marketing channels: (1) direct marketed through U-pick (customer harvested) or on-farm sales (grower harvested); (2) fresh sales via local stores or shipped to more distant markets; and (3) processed as frozen fruit, puree, dried, or juice—processed fruit may be sold directly to consumers in small retail packages, but it is often purchased by food manufacturers to make other products such as ice cream, yogurts, jams, jellies, juice blends, baked goods, cereals, and wines, for example.

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Chapter 1: Berry crops: Worldwide area and production systems 5

Production systems vary depending on whether the main market is for processed or fresh fruit. However, farms that have a fresh market focus may process a portion of their production that does not meet fresh fruit grade standards, when fresh prices are too low, or when there is a demand for processed fruit. Thus many growers access more than one marketing channel and grow a range of berry crops (and other crops as well) to diversify and improve their chances of success and minimize risk. Growers who are tar-geting large fresh or processed markets often work with a local wholesaler (fresh shipper or processing plant or “packer”) who sets prices and provides guidelines for harvesting and packaging. Some wholesalers provide the proprietary cultivars grown.

Most berry crops are grown with conventional or integrated pest man-agement practices. However, there is an increasing market demand for organically grown berry crops and thus organic acreage is increasing.

This chapter details current berry crop acreage and production world-wide. The botanical classifications and growth and development of the major and many of the minor berry crops are described to provide the necessary fundamentals. The most common production systems are described by crop, with any differences among regions noted.

1.2 Worldwide berry crop production

1.2.1 Strawberry

There were more than 600,000 acres and 3.9 million tons of strawberries produced worldwide in 2005 (Table 1.1). More than half the acreage was in Europe, with Poland, Serbia and Montenegro, Germany, Ukraine, and Italy

Table 1.1 Production of Major Berry Crops Worldwide, in Descending

Order of Area Planted, 2005

Berry crop Region Area (acres)

Production (tons) Strawberries Africa 16,264 207,130 Asia 134,670 721,566 Central America 1,142 10,869 Europe 327,205 1,241,718 Middle East 35,360 225,475 North America 75,664 1,299,600 Oceania 4,643 33,547 South America 14,685 131,964 World total 609,633 3,871,869

Red and black currants Asia 179,222 445,417

Europe 219,069 486,675

Oceania 3,855 7,826

World total 402,146 939,918

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being the leading producers. In fact, 40% of the acreage in Europe is in Poland, with most of their production being processed. There is strong year-round demand for high-quality fresh strawberries in Europe. Fresh strawberries are produced in southern Spain and Italy from February to May and are exported to countries in north and central Europe. Traditional cropping systems are

Table 1.1 (Continued) Production of Major Berry Crops Worldwide, in

Descending Order of Area Planted, 2005

Berry crop Region Area (acres)

Productions (tons) Blueberries—Highbush Africa 741 350 Asia 1,754 1,445 Europe 9,736 19,535 North America 74,585 152,350 Oceania 2,434 3,650 South America 18,039 17,500 World total 107,289 194,830

Blueberries—Lowbush North America 172,840 100,750

World total 280,129 295,580

Red raspberries Africa 163 143

Asia 100,428 131,468 Europe 104,069 230,918 North America 21,164 82,783 Oceania 927 761 South America 25,950 57,320 World total 252,701 503,393 Gooseberries Asia 42,056 67,847 Europe 54,520 83,050 World total 96,576 150,897 Cranberries Asia 26,687 36,927 Europe 247 551 North America 46,245 377,056 South America 1500 3000 World total 74,679 417,534 Blackberries Africa 247 220 Asia 3,830 29,051 Central America 4,052 1,753 Europe 19,007 47,386 North America 17,690 65,170 Oceania 734 4,023 South America 3,939 6,975 World total 49,499 154,578

Black raspberries Asia 50 250

North America 1,300 235

World total 1,350 485

Source: United Nations Food and Agriculture Organization (FAO) (strawberry, cur-rants, gooseberries); Strik and Yarborough1_{(Brazelton, D., personal communication;}

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used to produce fresh fruit in northern Europe and Scandinavia from June through August. Protected culture using greenhouses and tunnels is used in many European countries to provide “out-of-season” fresh fruit for 11 months of the year (from end of February until mid-January) in temperate climates. The next largest production region for strawberries is Asia (Table 1.1), where 65% of the acreage is in the Russian Federation, 14% each in Korea and Japan, and 5% in Kazakhstan.

The United States had 51,595 acres of strawberries and 1.1 million tons, making it the largest producer in North America (Table 1.1). In the United States, 63% and 13% of the total acreage is in California and Florida, respec-tively, where strawberries are produced using annual production systems and more than 75% is fresh marketed. Fresh strawberries are available year-round using traditional annual and perennial production systems. Other states in the United States produce strawberries predominantly using perennial production systems, with the third largest producer, Oregon (6% of acreage), processing more than 95% of their production. It is difficult for states like Oregon, that produce high-quality processed strawberries, to com-pete with processed fruit produced at lower cost in Mexico and California. For example, strawberry acreage in Oregon has declined from 7800 acres in 1988 to 2200 acres in 2005. Most of this decline can be attributed to compe-tition from processed fruit produced elsewhere, particularly in California. Historically California strawberry production is about 75% fresh marketed; however, they still produce more than 250 million pounds of processed fruit. While this processed fruit is considered inferior to that from cultivars bred specifically for processing produced in Oregon and other areas of the Pacific Northwest, it is a by-product and is sold at lower cost. In addition, yield in the annual production system used in California is up to six times higher than in the perennial systems used in the Northwest. These higher costs of production have made it difficult for Oregon growers to compete. It is likely that certain manufacturers will always demand premium quality fruit for certain products, so the future for a small, niche market industry in Oregon, for example, seems good.

Mexico produced 165,632 tons of strawberries on 13,378 acres using annual production systems. Mexico typically exports about 30,000 tons/year, of which 70% is processed and 30% is fresh. Most of the exports are to the United States, but fruit is also shipped to Canada, Japan, and Europe. In 2005, Canada had more than 10,600 acres producing strawberries in peren-nial production systems for local fresh markets and processing.

More than 72% of the strawberries in the Middle East (Table 1.1) are grown in Turkey. Other strawberry-producing countries in this region are Iran (21%), Israel (3%), Lebanon, Palestine, Cyprus, and Jordan. Strawberry production in Turkey has increased considerably over the last 10 years. Strawberries are produced in most areas of Turkey, mostly on small family farms.

Egypt and Morocco accounted for 84% of the total acreage in Africa (Table 1.1). There is also some strawberry production in South Africa, Tunisia, and Zimbabwe. Production in most areas uses Californian cultivars in annual

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production systems. Fresh fruit from Egypt is exported mainly to the United Kingdom.

In South America (Table 1.1), strawberries are planted in Chile (27% of acreage), Peru (24%), Columbia (13%), Venezuela and Brazil (7%), Paraguay (5%), and Ecuador (3%). Annual production systems using Californian cul-tivars are common. Nearly 60% of strawberries in South America are pro-duced between June and November, with the remainder propro-duced between November and May. About 50% to 70% of the strawberries are shipped fresh, while 30% to 50% are shipped frozen.

There is also some strawberry production in Central America, mainly in Guatemala and Costa Rica, and in Oceania, with 79% of the acreage in Australia (Table 1.1).

Currently it is not easy to obtain acreage information on organic straw-berry production. However, there is some organic production in most regions. In California, where accurate statistics are reported, there were 965 acres of organic strawberries in 2006 (3% of the total acreage).

Fresh strawberries are most commonly shipped in clamshell containers. Strawberries are processed as individually quick frozen (IQF), bulk frozen, sliced and sugared (“4 + 1”; 4 pounds fruit + 1 pound sugar), freeze-dried, pureed, or juice/concentrate.

1.2.2 Raspberry

1.2.2.1 Red raspberry

In terms of area planted, red raspberries are the fourth most important berry crop in the world (Table 1.1). Europe accounts for the largest portion of red raspberry acreage. Serbia and Montenegro (40% of the acreage) and Poland (34%) are the largest red raspberry producers in Europe, together producing more than 161,500 tons in 2005, mainly for processing. Other countries pro-ducing red raspberries in Europe are the United Kingdom (4%), France (3%), Hungary (3%), Spain (3%), Bulgaria (3%), Germany (3%), and Belgium, Croatia, Czech Republic, Estonia, Finland, Norway, Portugal, Romania, Swit-zerland, Sweden, Slovakia, The Netherlands, Italy, Ireland, and Denmark. More than 60% of the total production in most western European countries is fresh marketed.

Asia accounts for about 40% of world acreage (Table 1.1); however, most (81%) of Asia’s production is in the Russian Federation. More than 12,350 acres were reported in the Ukraine, but an additional 30,000 acres of wild raspberries are harvested. The next largest raspberry producer in Asia is Korea, with 3212 acres; much of their production is locally used to produce wine. Other countries in Asia with red raspberry acreage are the Republic of Azerbaijan, the Republic of Moldova, and China.

Chile is the only country in South America with significant red raspberry acreage (Table 1.1). Only 7% of Chilean production is for domestic use, the rest is exported, mainly (85%) as processed product. Frozen red raspberries from Chile are exported to Europe, the United States, Canada, and Australia.

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North America produces 16% of the red raspberry tonnage in the world (Table 1.1). The United States has about 14,826 acres, mostly in Washington State, but significant production also occurs in Oregon and California. Canada has 5560 acres, mostly in British Columbia, and most of this fruit is processed. The 778 acres in Mexico are mainly grown for the fresh export market. In Oceania, most of the acreage is in New Zealand (80%). Zimbabwe and Morocco produce red raspberries in Africa (Table 1.1).

Red raspberries for the fresh market are most commonly sold in clam-shell containers. Raspberries are processed as IQF, bulk frozen, freeze-dried, puree, or juice/concentrate.

1.2.2.2 Black raspberry

The only countries reporting significant acreages of black raspberries are China and the United States, for a total world production of 485 tons from 1350 acres (Table 1.1). Korea has substantial new, but unreported, acreage being used for the production of berries for liqueur. In the United States, 99% of the black raspberry acreage is in Oregon, with almost all of the production processed as bulk frozen, puree (seedless), freeze-dried, or juice/ concentrate.

1.2.3 Blackberry

Blackberry acreage worldwide has increased an estimated 45% in the last 10 years. In 2005, there were about 49,498 acres of blackberries planted and commercially cultivated worldwide (Table 1.1). Blackberries are now more available to consumers. In 1990, most of the blackberry production in the eastern United States was U-pick or direct marketed and less than 2% was processed.3_{In contrast, in 1990 more than 90% and 50% of the trailing} blackberry crop in Oregon and California, respectively, was processed. Black-berries were not found on grocery store shelves in the eastern United States, and only rarely in the western United States in 1990.4_{However, in the late} 1990s, Chester Thornless became a major shipping blackberry, as it was found to have good fruit firmness. Navaho, from the University of Arkansas, was found to have excellent shelf life and could be shipped. These and other cultivars contributed to a major shift in the production outlook for blackber-ries from that of a locally marketed crop to one shipped for retail marketing.4 Also, the shipping of blackberries from Chile, Guatemala, and Mexico to the United States provided fresh blackberries during the “off-season” autumn, winter, and spring months and increased consumer awareness of this berry crop and consequently increased sales of U.S.-produced “in-season” fruit.

Wild blackberries, not included in Table 1.1, still make significant con-tributions to worldwide production, and although accurate data are hard to obtain, there were an estimated 19,770 acres of wild blackberries harvested in 2005 with a total reported production of 14,837 tons.2_{In some regions, the} fruit harvested from wild blackberries may negatively impact sales of com-mercially grown fruit.

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Worldwide blackberry production was 154,578 tons in 2005, not includ-ing the wild production mentioned above (Table 1.1). The largest blackberry production region is Europe, with Serbia accounting for 69% of the black-berry acreage in Europe. Ninety percent of Serbia’s production is processed and exported. Hungary was the next largest producer in Europe, with 3950 acres (21% of the total area) and 13,227 tons. Countries in Europe with 250 acres or more are the United Kingdom, Romania, Poland, Germany, and Croatia. The area in Poland has doubled in the last 10 years. There were 550 tons produced in 2005, with 80% processed, and most of this was exported, as was most of their fresh production.

The United States accounted for 67% of the blackberry acreage in North America, the second largest in the world, after Serbia. The area planted in the United States increased 28% from 1995 to 2005. The United States had the highest production—35,099 tons—in the world in 2005. Sixty-five percent of the blackberries cultivated in the United States are planted in Oregon— 7755 acres. More than 95% of the total production of 25,185 tons was pro-cessed, with the remaining marketed fresh, and all for domestic use.

The next largest blackberry-producing state in the United States is California, with 700 acres and 2600 tons in 2005. Most of the blackberry production in California is now located on the north-central coast and has a fresh market focus from mid-May through August. Other blackberry-producing states are Texas, Arkansas, and Georgia.5

Mexico accounts for 32% of the planted area in North America, with 5683 acres. Blackberry production in Mexico has increased from 568 acres in 1995 and is projected to grow to at least 12,355 acres by 2015. Most of the Mexican produc-tion targets fresh export markets to the United States. In 2004, Mexico exported 8245 tons to the United States, more than double their export volume in 2002.

In Central America (Table 1.1), Costa Rica (3830 acres) and Guatemala (222 acres) reported commercial production. Of the 1653 tons produced in Costa Rica, less than 15% was exported. Currently most is used for local processing and fresh consumption. Guatemala is the main country in Central America that ships fresh blackberries to the United States.

Ecuador accounts for 53% of the planted area in South America (Table 1.1), with 2100 acres. There was an estimated 30% growth in planted area from 1995 to 2005, but little growth is projected for the next 10 years. Only 15% of their estimated 1421 tons of production is exported for the fresh market, mainly due to the soft fruit of the species they grow (Rubus glaucus Benth.) and the Mediterranean fruit fly (Ceratitis capitata Wiedemann). Chile has 1111 acres of commercial blackberries with a total production of 4275 tons, not including the 6393 tons harvested from wild plantings and exported as a processed product. The area planted increased 50% from 1995 to 2005 and is projected to be 1975 acres in 2015, provided competition from Mexico in the fresh market does not adversely affect the cost of production and com-petitiveness in the processed portion of their industry. In 2004, Chile exported 10,670 tons of processed fruit (55% to 65% was harvested from introduced wild species) and 210 tons of fresh fruit. Their fruiting season is

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from November to March. Brazil had 617 acres and produced 860 tons in 2005, with only 15% exported.

China accounted for all of the production in Asia (Table 1.1). Most of China’s production is in the Jiangsu Province, but the newest regions, the Liaoning, Shandong, and Hebai Provinces, are projected to grow the most in the next 10 years, when China is expected to have 5436 acres. Most of the production in China is processed, with 70% of processed fruit and 10% of their fresh production exported.

Most of the blackberry area in Oceania (Table 1.1) is planted in New Zealand, which had 640 acres and 3690 tons in 2005. The area in Oceania is projected to grow by about 35% in 10 years. The fruiting season in New Zealand is from November through April, with almost all of their blackberry production consisting of trailing types, mainly Boysen. Almost all of their production is processed, with 55% of that exported.

South Africa is currently the only African country with blackberry pro-duction (Table 1.1). However, no fresh fruit is exported because of the dis-tance to the major markets of Europe.

Projections for the greatest growth in the next 10 years are in Romania (900%), Poland (200%), Mexico (117%), Chile (76%), Hungary (50%), China (42%), and the United States (20%). There may be 66,797 acres of commercial blackberries worldwide, not including production from harvested wild plants, in 2015.2

Blackberries for the fresh market are most commonly sold in clamshell containers. Blackberries are processed as IQF, bulk frozen, puree (with or without seeds, depending on the cultivar), freeze-dried, or juice/concentrate.

1.2.4 Blueberry

Blueberries have become a major crop worldwide. Strong markets for pro-cessed and fresh fruit have resulted in good returns for growers and an increase in planted area. The growth in markets and production is related to the positive health benefits of blueberries. These benefits have been used in marketing campaigns since 1997. Over the last 10 years, demand for blueberries has exceeded supply. New cultivars, better adapted to “nontra-ditional” growing areas, have expanded production worldwide. From 1995 to 2005, worldwide highbush blueberry acreage increased by 90%.

In many areas of the world, wild species of blueberries are harvested for personal and commercial use. Data on total production are often difficult or impossible to obtain. For example, Vaccinium uliginosum L. is harvested in China,

Vaccinium myrtillus L. in Europe, and various species in the United States, often

marketed as “huckleberries.” I will not include information on the production of any native Vaccinium species here, other than the lowbush blueberry.

1.2.4.1 Lowbush blueberry

Lowbush blueberry fields consist mainly of native clones of Vaccinium

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on the region. In Canada and the United States, native stands are managed and harvested for commercial production. Fruit are often marketed as “wild blueberries,” with more than 97% of the total production being processed. In 2003, processed lowbush blueberry fruit accounted for 68% of the total pro-cessed fruit (all types of blueberries) produced in North America and they are expected to continue to account for a significant share of this market.

In 2003, the total area of lowbush blueberries managed in North America was 172,845 acres, a 33% increase from 10 years earlier.1_{Since lowbush} blueberries are native, this increase in area reflects a larger portion of native stands being managed for harvest because of the strong blueberry market. There were 65,442 acres of lowbush blueberries in the United States, mainly in Maine, and 107,404 acres in Canada, mainly in Quebec, Nova Scotia, and New Brunswick. Only half of the total area of lowbush blueberries is har-vested annually because of alternate-year pruning practices.5_{Total lowbush} blueberry production in North America in 2003 was 111,058 tons, with approximately 99% sold for processing.

The managed area of lowbush blueberries in North America is expected to increase by 10% by 2013.1_{The major limitation for expansion of this} industry is finding native stands that can be economically brought into production.

1.2.4.2 Highbush blueberry

In 2005, there were an estimated 107,289 acres of highbush blueberries

(Vaccinium corymbosum L.) planted worldwide with a total production of

196,900 tons, a 20% and 51% increase in acreage and production, respectively, from what was reported in 2003.6_{North America accounted for about 70%} of the planted area and 77% of the total highbush blueberry production in the world (Table 1.1). Acreage in North America increased an average of 2535 acres/year from 2003 through 2005. Most of the North American acre-age was in the United States—60,975 acres—but there were 13,500 acres in Canada, mainly in British Columbia, and about 180 acres in Mexico in 2005. South America accounted for about 17% of the world area in 2005 (Table 1.1). Fruit is harvested by hand from the end of September through April, depend-ing on the country and region. Most of the fruit is exported to markets in the Northern Hemisphere. Blueberry production in South America started in Chile, which still accounts for 62% of the area planted and 80% of the total production. The remaining blueberry production is in Argentina.

In Europe, 95% of the total production (Table 1.1) is marketed in Europe. There were an estimated 3954 acres in Poland, 3954 acres in Germany, 741 acres in France, 852 acres in The Netherlands, 593 acres in Spain and Portugal, 445 acres in Italy, and 49 acres in the United Kingdom.

Oceania accounted for about 2% of the world’s blueberry area in 2005 (Table 1.1), with about half the area in each of New Zealand and Australia. South Africa had 741 acres and produced 350 tons of blueberries in 2005 (Table 1.1). There is tremendous interest in blueberries in Asia. Plantings are expected to increase steadily in this region. Japan has about 1112 acres and

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China 642 acres (Table 1.1). However, interest in planting blueberries is strong in both countries. For example, in China there may be more than 1500 acres planted by 2008.

Total highbush blueberry production in the world in 2005 was 194,830 tons, with approximately 63% sold for the fresh market. Blueberries for the fresh market are most commonly sold in clamshell containers. Blueberries are processed as IQF, bulk frozen, freeze-dried, pureed, or juice/concentrate.

Many areas producing highbush blueberries have some limitations to expansion of the area planted, particularly in North America and Europe. These limitations include cold winter climate and insufficient cold hardiness of the present cultivars, lack of suitable soils, insufficient planting stock, pressures for urbanization, and the cost of establishment. Still, many project significant growth in the planted area of highbush blueberries in the next 5 to 10 years. The markets for fresh and processed fruit will need to continue to be strong to support the projected increase in supply.

1.2.5 Cranberry

There were a reported 74,679 acres of cranberries harvested worldwide in 2004 (Table 1.1). The United States is the world’s largest producer, with 39,200 acres of the large-fruited cranberry (Vaccinium macrocarpon Ait.) and 74% of total world production. In the United States, Wisconsin and Massachusetts have the largest cranberry acreage, accounting for 80% of the total. Other states producing cranberries are New Jersey, Oregon, and Washington.

Belarus has the second largest area, with 19,768 acres, but the yield of the small-fruited cranberry (Vaccinium oxycoccos L.) they produce is relatively low, with a total production of 25,353 tons. In comparison, Canada had the second highest production in the world, harvesting 68,556 tons of large-fruited cran-berry from 7045 acres. The area in Europe is currently reported as 247 acres, all in Romania; however, there are commercial cranberry plantings in Ireland and Poland that are not yet reported in official statistics. Other countries producing the small-fruited cranberry are Ukraine, Latvia, and the Republic of Azerbaijan in west Asia. In South America, the only country producing the large-fruited cranberry on established beds is Chile, with 1500 acres (Table 1.1). The majority of cranberry production worldwide is processed. In the United States, 94% of total production was processed in 2004. Cranberries are processed for juice and sauces, and are dried. Chile exported 40 tons of fresh cranberries in 2004; however, fresh cranberries in the Northern Hemi-sphere are typically only sold during Thanksgiving (October in Canada and November in the United States) and Christmas. Fresh cranberries are stored from harvest (September or October) until the time of sale.

1.2.6 Gooseberry and currant

There were 96,576 acres of gooseberries (Ribes uva-crispa L.) and 402,146 acres of red and black currants (Ribes rubrum L. and Ribes nigrum L., respectively) worldwide in 2005 (Table 1.1). Currants are produced mainly in Europe and

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Asia, with black currants being the most common type grown; black currants are mainly processed into juice, but they are also used for jams, jellies, liqueurs, and colorings.7_{Almost all of the currant acreage in Asia is planted} in the Russian Federation. In Europe, countries with currants are Poland (47% of acreage), Germany (23%), Ukraine (5%), and the United Kingdom, Austria, the Czech Republic, France, Estonia, Denmark, and Finland, all with 2% to 3% of European acreage. The predominant acreage of red currants is in Poland and Germany, with lesser acreages in Belgium, France, Holland, and Hungary.7_{Red currants are used mostly for juices and other processed} food items, often in combination with other fruits. White currants are used in parts of Europe for baby food and in Finland for sparkling wines.8_Ninety percent of the acreage in Oceania is in New Zealand. Although some com-mercial acreage of gooseberries and currants exists in North and South America, it is relatively small and scattered. For example, currants are pro-duced for the fresh market in Chile and for the fresh and processed markets in the United States (Oregon).

Gooseberries are mainly grown in Asia and Europe (Table 1.1), with the largest area, 42,000 acres, in the Russian Federation and 30,885 acres in Germany. The next largest producer is Poland, with 8400 acres. Although some commercial acreage of gooseberries exists in North America, it is rel-atively small and scattered. Gooseberries are grown for the fresh market and processing, mainly canning, in Oregon. Worldwide, gooseberries are pro-cessed mainly for jams and are sold to a limited extent for the fresh market.

1.2.7 Miscellaneous minor berry crops

1.2.7.1 Lingonberry

The commercial acreage of lingonberries in established plantings is estimated at 70 acres worldwide. Actual production statistics for this crop are difficult to obtain. Most of the lingonberry production worldwide is harvested from wild stands.

1.2.7.2 Hardy kiwifruit

Kiwifruit is native to Southeast Asia. There are more than 50 species in the genus Actinidia, and many have commercial potential. The most common kiwifruit species grown commercially is Actinidia deliciosa cv. Hayward. Con-sumers are very familiar with this brown, fuzzy fruit. Hayward is grown commercially in New Zealand, Italy, Japan, France, Australia, Greece, Chile, and California. Hardy kiwifruit [Actinidia arguta (Siebold & Zucc.) Planch. ex Miq], however, are much more limited in their production and, unlike Hayward, are often marketed along with other berry crops.

Ananasnaya is the most widely grown cultivar of hardy kiwifruit in the world and may also be known or marketed under alternate names including “baby kiwifruit,” “grape kiwi,” “wee-kee,” and “cocktail kiwi.” In 2003, about 250 acres of Ananasnaya were grown commercially worldwide, in the United States, New Zealand, Canada, Chile, Italy, France, Germany, and

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The Netherlands9_{more than one-third of this acreage was in Oregon. Fresh} fruit of Ananasnaya have been well received in the San Francisco and Los Angeles, California, markets and in Japan, fetching high prices. In addition, private industries are working on developing processed products.

The commercial acreage has been limited mainly by marketing factors, such as development of fresh markets for this relatively unique fruit, the range in fruit size, the limited ripening period, and the relatively short storage and shelf life compared to fuzzy kiwifruit. The continued development of processed markets likely will strengthen this industry.

1.2.7.3 Other berry crops

Every culture around the world has native crops that are important locally and some of these have become important berry crops.10_{Other berry crops} grown commercially include the elderberry (Sambucus canadensis L.), in North America and its counterpart Sambucus nigra L. in Europe. The purplish-black berries, about 1/4 in. in diameter, are produced on large cymes up to 1 ft in diameter. The stems of the American elder have long been used for musical flutes and pipes for conducting liquids. North American Indi-ans and early pioneers adapted the hollow stems for use as a tap to draw sap from sugar maple trees. Tannin in the bark and roots of elderberry was used in tanning leather. The leaves, flowers, and fruit provided dyes for leather, baskets, and other articles made by North American Indians. The berries and oil pressed from seeds have been used to flavor wine. All parts of the elderberry have been used in medicine, and the powdered, freeze-dried, encapsulated fruit of S. nigra is a major use for this crop. At present, elderberry fruit is used for various culinary purposes: in sauces, alone or combined with other fruit in tarts and pies, fruit juice, jelly, and red wine.11

Saskatoons, also called juneberries or serviceberries (Amelanchier alnifolia Nutt.), are grown commercially mainly in Alberta and Saskatchewan, Canada. Various species of Amelanchier are used as ornamentals for their showy flowers and edible, dark purple fruit that look like blueberries. However, this plant does not produce true “berries”; botanically, this species produces a pome fruit. The fruit was used by North American Indians in making pemmican, a semidry mixture of fruit and meat. Early pioneers used this as a major source of fruit. The fruit can be eaten fresh, in pies or other baked desserts, canned, frozen, or made into wines, jellies, or syrup.

The chokeberry [Aronia melanocarpa (Michx.) Elliott] is grown commer-cially as a processed fruit product in eastern Europe and to a limited extent in North America. Plants produce dark purple berries, about 1/4 in. in diameter, that are used mainly for juice production.

Some wild blueberries, commonly called “huckleberries,” are not only har-vested from wild stands, but are planted and commercially cultivated. An exam-ple of this is the “evergreen huckleberry” Vaccinium ovatum Pursch.), grown to a very limited extent in established plantings in Oregon. The small, dark blue to purple fruit are processed and mainly used for “huckleberry” jam.

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1.3 Growth and development

Vegetative and reproductive growth of berry crops is influenced by environ-ment, particularly photoperiod and temperature, soil type, and cultural prac-tices such as fertilization, irrigation, and production systems. This chapter highlights the stages of growth and fruit development. Cold hardiness is not covered here, but is well reviewed in other publications.8,12–18

1.3.1 Strawberry

The cultivated strawberry (Fragaria×ananassa Duch., family Rosaceae) is a perennial plant adapted to a wide range of climates. There are many other species of Fragaria found worldwide, however, the only other species grown commercially to any extent are Fragaria vesca L., the wood or alpine straw-berry, and Fragaria chiloensis (L.) Mill., the beach strawberry.

The strawberry plant has trifoliate leaves arranged spirally around a compressed stem, called a crown.19_{Buds in the axils of each leaf may develop} into a branch crown, inflorescence, a runner, or remain dormant. Branch crowns tend to develop under short day length (less than 10 hours), whereas runners are promoted under long days (more than 10 hours). Runners consist of an aboveground stem with a new daughter plant produced at the second node. Daughter plants may also produce runners, thus leading to a runner “string.” The original plant established is often called the “mother plant.” Some types or cultivars of strawberry produce more runners than others. Runner production may also be manipulated through chilling received in cold storage, as is done in the California production system. Roots arise from the base of the crown, with 90% of the root system found in the upper 6 in. of soil.20

The two main types of strawberry grown worldwide are short-day types (called “June bearers” in the northern hemisphere) and day-neutral types. Short-day cultivars initiate flower buds when the day length or photoperiod is less than 14 hours, whereas day-neutral cultivars typically initiate buds every 6 weeks throughout the growing season.13_{However, at low} tempera-tures (about 50°F to 59°F) most cultivars initiate flowers regardless of the photoperiod, while at high temperatures (about 77°F), flower bud initiation is almost inhibited.13_{The impact of light intensity and temperature on} straw-berry plant growth is well reviewed by Darnell.13

Strawberry inflorescences often produce a terminal flower (primary), two secondary, four tertiary, and eight quaternary flowers.20_{However, as} breeding programs have selected for larger fruit, they have selected for much simpler inflorescences that commonly contain only one to three flowers. Individual flowers typically have 10 sepals (calyx), 5 petals, 20 to 30 stamen, and 60 to 100 pistils, depending on the flower order.21_{The flowers are mainly} pollinated by bees.

The strawberry is an aggregate or accessory fruit composed of a fleshy, red receptacle with achenes (fertilized ovules, often called “seeds”) arranged spirally on the outside of the receptacle. Growth of the receptacle depends

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on the successful fertilization of the ovules and the size and shape of the mature fruit is a function of the number and arrangement of achenes formed.22_{Fruit development from pollination to ripe fruit ranges from 20 to} 50 days, depending on the cultivar and temperature. The primary fruit ripens first and produces the largest fruit (“berry”), then the secondary, and so on.

1.3.2 Raspberry and blackberry

The red raspberry (Rubus idaeus L.), the black raspberry (Rubus occidentalis L.), and the blackberries (Rubus sp.) belong to the family Rosaceae. This group or genus (Rubus) is collectively called “brambles” in eastern North America and “caneberries” in western North America. Most blackberries and rasp-berries have spines, although spine density can vary considerably among cultivars, with some being genetically thornless.

Raspberry and blackberry plants have perennial root systems and crowns (base of the plant). However, the canes are biennial, living for only 2 years. Cane growth (increases in length) occurs only in the first year, when canes are called primocanes. In year two, canes are called floricanes. These canes flower, fruit, and then die after fruiting. In any year, except the planting year, there are both cane types present.

1.3.2.1 Raspberry

The red raspberry (R. idaeus) is commonly divided into two types based on fruiting habit: “summer bearers” or floricane fruiting types (e.g., Tulameen, Meeker, Glen Ample), and “primocane fruiting” types (e.g., Heritage, Autumn Bliss, Polka). The only black raspberry harvested commercially is R. occidentalis (e.g., Munger). Purple raspberries (e.g., Royalty), hybrids between red and black raspberries, are grown to a very limited extent, mainly in eastern North America. Yellow-fruited R. idaeus, in which the fruit color is due to a recessive mutation, is also grown in small quantities for specialty markets.

Wherever raspberry species are found, they have been harvested from the wild; however, several species have interest beyond their area of origin.10 Raspberry species harvested in the wild include Rubus chamaemorus L., the cloudberry, and Rubus arcticus L., the arctic raspberry, both native to alpine and circumpolar regions and having a dwarf, herbaceous, annual bearing habit. Hybrids of the European R. arcticus and the American Rubus stellatus are marketed in northern Europe.23

Primocanes are produced from buds at the base of floricanes at the crown or from buds on roots in red raspberry. Black raspberries only produce new primocanes from buds on the crown. Generally, in summer-bearing red and black raspberries, primocanes are vegetative the first year and fruit the second year on the entire length of the floricane. Primocane fruiting rasp-berries produce a relatively large crop at the tip of the primocane and will produce a floricane crop on the base of the second-year cane.

Raspberries have an extensive root system. Roots start growing in the spring after bud break. If water is adequate, most root growth occurs in midsummer and growth continues in the fall after top growth has stopped.

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In summer-bearing raspberries, flower bud initiation for next year’s crop occurs as the day length shortens and temperatures start to cool in late summer. Flower bud development starts at the tip of the cane and progresses basipetally.

Flower bud initiation in primocane fruiting cultivars is not dependent upon photoperiod or cooler temperatures, but rather is based on the phys-iological age of the cane, starting at the tip.24,25_{Carew et al.}26_{reviewed how} the growth cycles of summer-bearing and primocane fruiting raspberries are controlled by the environment, the cultivar, and cultural practices.

Once plants enter dormancy, a certain number of chilling hours (tem-peratures between 32°F and 45°F) are required before the plant can grow normally. Although the exact chilling requirements of many cultivars are not known, many of the summer-bearing red raspberries grown in the northern hemisphere have a chilling requirement of 800 to about 1400 hours. Pri-mocanes overwinter as dormant canes and become floricanes when growth starts the following spring.

Buds break along the floricane producing fruiting laterals, the lengths of which are cultivar dependent. Cultivars that are suited to machine har-vesting generally have fruiting laterals that are not too short or too long and are not brittle. The range in flower opening time along the fruiting lateral, coupled with a slightly earlier emergence of laterals at the tip of the cane, leads to a range in fruit ripening time within a cultivar. Most summer-bearing cultivars have a ripening season of about 30 days, although some have a season as long as 55 days.

Raspberry flowers have five sepals, five petals, many stamens, and many pistils arranged spirally around a receptacle. Commercial red and black raspberries are self-fertile, in that a cross pollinator is not required. However, they do require insect/bee transfer of pollen to the pistils. Insufficient pol-lination or fruit set within a flower leads to the development of crumbly fruit. Some viruses, such as raspberry bushy dwarf virus, may lead to symp-toms of crumbly fruit.17

It takes about 30 to 35 days for raspberry fruit to mature after pollination. Individual fruit typically weigh from 2.5 to 5 g, depending on the cultivar. For maximum productivity, flavor, and sweetness, fruit must reach full matu-rity and full size before harvest. However, fruit firmness decreases in the later stages of fruit maturation. Fruit firmness is also cultivar dependent.

The “berry” is an aggregate fruit consisting of many drupelets, each of which contains a pyrene (seed). The drupelets are spirally arranged around a white-colored receptacle. When picked, the berry separates from the recep-tacle, or “torus,” yielding a hollow, thimble-shaped fruit. The ease of fruit removal when ripe is cultivar dependent, with those suited for machine harvesting requiring easy fruit removal.

1.3.2.2 Blackberry

Blackberries are often classified according to their cane architecture into three types: erect, semierect, and trailing.27_{Erect blackberries produce primocanes}

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from buds at the base of floricanes at the crown or from buds on roots, whereas trailing and semierect types only produce new primocanes from buds on the crown. With the exception of the primocane fruiting erect types, primocanes are vegetative the first year and fruit the second year on the entire length of the floricane.

Blackberries have an extensive root system. Primocanes emerge in the spring, with rapid growth under suitable temperature conditions. Erect and semierect blackberries produce primocanes that grow upright, with vigor dependent on the cultivar and growing conditions. The primocanes of trail-ing blackberry are not self-supporttrail-ing and will grow along the ground. Canes will continue to grow in length until cold weather in the fall limits their development.

In general, flower bud initiation in blackberry occurs under short day length and low temperature. However, the time of flower bud initiation and the pattern of development on the cane can vary with the growing location and the blackberry type or cultivar.28,29_{Primocane fruiting blackberries} pro-duce fruit on the top one-fifth or so of the cane during the latter part of the growing season.

The chilling requirement of blackberries has been reported to range from 200 to more than 900 hours, depending on the type and cultivar.30,31_Weather, specifically low winter temperatures, limits where blackberries can be grown.32_{In general, erect blackberries can survive much lower winter} tem-peratures (less than 5°F) than trailing types, and thorny cultivars are more winter hardy than thornless types.33

Blackberry flowers and fruit have a similar morphology to raspberries. The “berry” is an aggregate fruit consisting of many drupelets, each of which contains a pyrene (seed). The pyrenes of most trailing blackberries are much smaller or thinner than those of erect and semierect blackberry. In all black-berry fruit, the receptacle or “torus” separates from the plant when picked and is part of the fruit that is consumed. The ease of fruit removal when ripe is cultivar dependent, with those suited for machine harvesting requir-ing easy fruit removal.

It takes from 40 to 60 days for blackberry fruit to mature after pollination. Individual fruit typically weigh from 3 to 12 g, depending on the cultivar. Many blackberry fruit are not at their optimum flavor until they change from glossy black to dull black in color. For maximum productivity, flavor, and sweetness, fruit must reach full maturity and full size before harvest. How-ever, fruit firmness decreases in the later stages of fruit maturation. Fruit firmness is also cultivar dependent.

1.3.2.3 Raspberry-blackberry hybrids

Hybrids of red raspberry and blackberry are grown commercially. These are considered trailing blackberry types due to their growth habit. While Boysen and Logan have historically been very important commercially, the acreage of these, particularly Logan, has declined over the last 10 years. Other hybrids that are occasionally sold include Tayberry and Tummelberry.

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1.3.3 Blueberry

There are about 400 species of blueberry (Vaccinium sp., family Ericaceae). The most important blueberries cultivated worldwide are the northern high-bush (V. corymbosum), southern highhigh-bush (complex hybrids based largely on V. corymbosum and V. darrowi Camp.), and rabbiteye blueberry (V. ashei Reade), all native to eastern North America.34_{The lowbush blueberry in} northeastern North America (mainly V. angustifolium) is harvested from managed native stands. Various other species are harvested from the wild in many regions of the world. Like other ericaceous plants, blueberries thrive in acid soils with a pH between 4.2 and 5.5. All commercial blueberry species are deciduous and have a typical bush height at maturity of 1 foot in lowbush blueberry, 6 to 8 feet in highbush, and 12 feet in rabbiteye blueberry.

The roots of highbush and rabbiteye blueberries are very fine, fibrous, and lack root hairs.35_{Lowbush blueberries produce roots adventitiously from} rhizomes, or below-ground stems. Thus lowbush blueberries are maintained in solid beds without aisles, whereas highbush and rabbiteye types are planted in fields with aisles between rows of plants. The fine, fibrous roots of the blueberry require an open, porous soil. Most blueberry roots are found within the drip line of the bush and in the upper 18 inches of soil.

Blueberries produce simple buds—vegetative buds, producing a leafy shoot, and flower buds, producing only an inflorescence. Flower buds are large and almost spherical, whereas vegetative buds are pointed, small, and scalelike. Buds are found mainly on 1-year-old wood, with latent buds also occurring on older wood. Shoot growth occurs in two or more flushes per season, depending on the cultivar and the length of the growing season. The impact of light intensity and temperature on blueberry plant growth is well reviewed by Darnell.14

New canes develop from the crown (base) of the blueberry plant in early spring or from older wood higher up in the bush. These shoots, usually called “whips,” are extremely vigorous and often are the “renewal” wood for subsequent years’ production.

Flower bud initiation occurs under short day length in late summer and early fall,36,37_{usually on the tip of the current season’s shoot. Initiation} proceeds basipetally, with the number of floral buds per shoot affected by the cultivar, climate, and production practices. Flower bud development continues until temperatures become too cool in fall. Both flower and veg-etative buds require a period of dormancy, from 800 to 1200 hours between 32°F and 45°F in northern highbush blueberries, before growth begins again the following spring.15_{However, flower bud differentiation in southern} high-bush blueberries may occur through the winter without a dormant period.38 Blueberry plants flower in spring, with flowers at the tip of 1-year-old wood and the tip of the cluster opening first. The length of the bloom period varies with the cultivar, but can be affected by climate. Each flower bud contains from 8 to 16 potential flowers.15_{Flowers consist of sepals (calyx),}

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petals (a four- or five-lobed, urn-shaped corolla), 10 stamens, and a pistil.39 Commercial growers usually use honeybees for pollination. Although blue-berries are often self-fertile, cross-pollination increases fruit set and fruit size for many cultivars.40–42

The blueberry fruit is a true berry, consisting of an ovary with up to 100 seeds. The fruit of some species, particularly rabbiteye blueberries, contain stone cells, that contribute to fruit grittiness.14_{Ripe fruit are generally blue,} blue-black, or purple in color, but have a surface wax layer, the “bloom,” which may make the berry appear lighter in color.

The fruit development period ranges from 42 to 90 days for northern highbush,43_{55 to 60 days for southern highbush,}44_{70 to 90 days for} low-bush,45_{and 60 to 135 days for rabbiteye blueberry,}46_{depending on the} cul-tivar, weather, and plant vigor. The sugar content of the fruit will increase during maturation to about 15% when the fruit is ripe. Fruit size continues to increase after the fruit turns blue, due mainly to water uptake. Individual fruit typically weigh from 0.5 to 3 g, depending on the cultivar. Fruit flavor, much of it associated with the skin, increases during ripening, but not after harvest.

1.3.4 Cranberry

The large-fruited American cranberry (V. macrocarpon, family Ericaceae) is a low-growing, trailing, woody, broadleaf, nondeciduous vine. This species of cranberry is native to eastern North America. The small-fruited cranberry (V. oxycoccos) is not commercially cultivated in North America, but is har-vested in eastern Europe and Asia. Like blueberries, cranberries are adapted to acid soils and are best grown at a pH of 4.2 to 5.5.

Cranberry roots are very fine, fibrous, and lack root hairs. Roots are readily formed on decumbent stems when covered with a moist medium such as sand. Plants produce various types of shoots. Runners are horizontal stems ranging from 1 to 6 feet in length and spread profusely over the bed or canopy. The short, vertical branches in cranberry are called uprights. Uprights originate from axillary buds on the runners or from older uprights and grow for several years. Uprights are typically 2 to 3 inches long, but length is affected by light intensity and nutrition. Uprights can be either fruiting or vegetative (nonfruiting). In the Pacific Northwest, from 150 to 700 uprights per square foot have been documented in Stevens cranberry beds, with 10% to 65% of these being fruiting uprights.

Cranberry uprights produce one of two types of buds at their tip: flow-ering (fruit) and vegetative. Flower buds may contain from one to seven flowers, as well as leaves and a growing point. Axillary buds located at a leaf node either on the runner or on an upright are the source of new uprights or runners.

Bud break in cranberry typically occurs in early April, depending on weather conditions and vine nutrition. In April and May, some vegetative growth, including the development of new leaves, occurs. At the “hook”

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stage, the flower pedicels are visible on fruiting uprights. At this stage, the curve of the slender flower stem with the still-closed flower is said to resem-ble the neck and head of a crane, thus suggesting the name “craneberry,” which was shortened to cranberry. Bloom begins around the first part of June and lasts from 3 to 6 weeks, depending on the growing region.

Each flower is borne individually, with one to seven flowers per upright. Normally, vegetative growth continues beyond the flowers. The normal flower consists of an inferior ovary with four cells, a calyx of four sepals, and a corolla of four petals that are pinkish white in color and deeply cleft. Eight stamens surround the pistil.47

The cranberry is self-fertile, however, some evidence indicates that cross-pollination may improve fruit set and berry size. Mixtures of cranberry cultivars, or off-types, are not unusual in commercial beds, although this is not desired from a management perspective. Honeybees are used for polli-nation in commercial plantings.

The ovary and calyx fuse to form a true berry that varies in shape and color. The berry consists of a relatively thin epidermis and four locules containing from 0 to 50 seeds, depending on seed set. A waxy cuticle covers the epidermis and contributes to the ability of the cranberry to resist moisture loss after harvest. Although the thickness of this waxy cuticle has been found to differ among cultivars, it is not related to the keeping quality of the fruit. A typical fruit weight is about 1 to 1.5 g.

Cranberry fruit go through several stages of color development, from green to white to red. Berries reach physiological maturity about 80 days after fruit set. After harvest, the cranberry vine enters dormancy and requires more than 1000 hours of chilling before normal growth resumes the following spring.

1.3.5 Gooseberry and currant

There are about 150 species of gooseberries and currants (Ribes sp., family Grossulariaceae) worldwide; approximately 18 of these have been used to develop modern cultivars. In addition to several species that have ornamen-tal landscape value, five subgenera of Ribes are grown for their fruit: black currants (R. nigrum), red currants (R. rubrum), white currants (variants of

R. rubrum), gooseberries (R. uva-crispa), and jostaberries (Ribes × nidigrolaria

Bauer), hybrids of black currants and gooseberries.8

Cultivated gooseberries and currants are woody, perennial, deciduous shrubs that normally grow from 3 to 5 feet tall. Jostaberries can grow to 8 feet tall. Plants develop root systems about 3 feet in diameter, with most of the roots in the top 16 inches of soil. Roots near the surface are especially abundant in root hairs.

Ribes produce simple buds, either vegetative or floral. Vegetative buds produce short shoots—spurs—in all except black currants, or longer shoots that have strong apical dominance, particularly in currants. Vigorous new shoots also originate from the base of the plant, providing an important source of renewal wood for future production. Leaves, arranged alternately

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along shoots, are lobed and are high in phenolic and terpenoid compounds. Black currant leaves and buds are used as medicinal herbs.48

Flower bud initiation for most Ribes occurs with short days and cool temperatures. Flower bud development is completed about 7 to 10 days before the flowers open. In black currants, flower bud development starts at the base of current-season shoots, progressing acropetally. In red and white currants, most jostaberries, and gooseberries, some flower buds are initiated on current-season shoots, but most are initiated on spurs, located on 1- to 3-year-old wood. Thus the flowers of black currants are produced on 1-year-old wood, whereas all other Ribes grown commercially produce flowers mainly on spurs of 2-year-old or older wood—this affects pruning practices. Once canes enter full dormancy, they must go through a period of chilling—800 to 1600 hours—before growth can resume the following spring. Gooseberries and currants are among the most cold hardy fruit crops, toler-ating −22°F to −31°F when fully dormant.

Currants and gooseberries can bloom early, making them susceptible to frost damage in northern production areas. Currants produce flowers on racemose inflorescences called “strigs.” Gooseberry and jostaberry flowers are borne in clusters of one to three, sometimes called fascicles. Ribes flowers are greenish yellow or red and are pollinated by bees and other insects. Although most red and white currants and gooseberries are considered self-fruiting, some black currant cultivars are considered partially or com-pletely self-sterile. The degree of self-fertility may differ with the cultivar, growing region, and perhaps other factors. Thus many recommend planting a pollinizer in commercial black currants.8

Red and white currant berries have a thin epidermis that tears when the fruit is picked from the pedicel. Thus these crops are harvested by picking the entire strig when all the berries are ripe. Black currants are more firm and can be stripped from the strig as individual fruit or entire clusters can be picked by hand.

1.3.6 Miscellaneous minor berry crops

1.3.6.1 Lingonberry

Lingonberries (Vaccinium vitis-idaea L.) belong to the family Ericaceae and are thus closely related to blueberries and cranberries. Lingonberries are native to the circumpolar boreal region, including Scandinavia, Europe, Alaska, and northern Canada, but are not widely cultivated. The lingonberry is known by many other common names, including lingon, alpine cranberry, dry-ground cranberry, foxberry, moss cranberry, mountain cranberry, northern mountain cranberry, cowberry, partridgeberry, red whortleberry, and rock cranberry.

Lingonberry is a low-growing, woody, perennial, evergreen plant that spreads by below-ground stems called rhizomes. Plants are typically 1 foot tall and produce urn-shaped, white or pink flowers. Flower morphology is similar to that of the blueberry. The fruit is a small, red berry ranging from 0.17 to 0.45 g in size.

Berry Fruit - Value-Added Products

Berry

Fruit

Value-Added Products

for Health Promotion

FOOD SCIENCE

AND TECHNOLOGY

Editorial Advisory Board

Berry

Fruit

edited by

Yanyun Zhao

Value-Added Products

for Health Promotion

Table of Contents

Preface

Editor

Contributors

Part I

Bioactive compounds

of berry fruits

chapter 1

Berry crops: Worldwide area

and production systems

Bernadine C. Strik

Contents

1.1 Introduction

1.2 Worldwide berry crop production

1.2.1 Strawberry

1.2.2 Raspberry

1.2.3 Blackberry

1.2.4 Blueberry

1.2.5 Cranberry

1.2.6 Gooseberry and currant

1.2.7 Miscellaneous minor berry crops

1.3 Growth and development

1.3.1 Strawberry

1.3.2 Raspberry and blackberry

1.3.3 Blueberry

1.3.4 Cranberry

1.3.5 Gooseberry and currant

1.3.6 Miscellaneous minor berry crops