MATERIALS AND EXPERIMENTAL METHODS

8.3.1 Raw Materials and

Fresh boneless mutton legs were obtained from Waitaki International Limited at Feilding and were separately packed in polyethylene bags, frozen and kept in a freezer (-1 8 °C) for 1 week before being packed in chilly bins with dry ice and delivered to Bangkok, Thaila nd by air. The mutton legs were finally kept in a freezer ( - 1 8 °C) at the Depart ment of Food Technology, Chulalongkorn University and later used in production of the meatballs.

Mutton raw material used in all experiments for the focus groups was the trimmed p ro duct. Trimming was done to assure that as little mutton fat and con nective tissue as possible was left i n the prepared product. Other raw materials and ingredients were as described in Chapter 4 (Section 4.1 .1 ).

Bread crumbs and fresh eggs were used in crumbing of the meatballs. The crumbs were slightly gold coloured.

The basic formulation, obtained from the work in New Zealand, was 75% mutton lean, 20% pork lean, 5% pork fat; with 4% tapioca starch, 2.5% salt, 0.25% sodium tripolyphos phate (STPP) , 0.75% white pepper, 0.8% garlic, 0.6% onion and 0.6% ginger (based on t h e total meats and fat weight).

8.3.2 of the Meatballs

The meatballs were made according to the methods described in Section 4.1 .2. I n the sequence of focus groups and sensory e valuation used in this part of the res earch, alteration of the process was made to improve the characteristics of the meatballs. This was because the Scharfen bowl chopper and sausage stutter were not available at t h e Food Technology Department, Chulalongkorn University. Instead, a National food processor, with the very high revolutions of its blades, was used. This equipment m ight result in t o o fine meat particles after chopping. Due to this expectation, a chopping time of 3 minutes was firstly used. This was reduced from 6 minutes, the chopping time normally used with the Scharfen bowl chopper in New Zealand. However, since the results from a series of trials showed that the meatballs were not rubbery enough, the chopping time was seq u e ntially increased from 3 minutes to 4 minutes and then to 5 minutes. Making of the cylinders before being segmented and formed i nto balls was done by using a Kenwood food processor. Crumbing was done manually by dipping the balls into mixed egg white a n d yolk and rolling the balls in the bread crumbs.

8.3.3 Focus and Evaluation

Focus g roups were organised by firstly recruiting a homogeneous group of six academic staff at the Department of Home Economics , Kasetsart University, Bangkok, who were available , willing to help and had good experience in testing food products. This g roup of participants was chosen because it was expected that the staff in this department would be very experienced in cooking and eating many varieties of foods and therefor� they could contribute ideas as to how the product could be improved. This group was regarded as the

Kasetsart focus group.

A second focus group comprising six post-graduate students at the Department of Food Technology, Chulalongkorn University, Bangkok was later organised to retest the meatballs made with the altered fo rmu latio n . The part icipants were competent and had good experience in testing food products and it was expected that they could also con tribute some useful ideas i n a panel discussion. This group was regarded as the Chulalongkorn focus group.

Figure 8.1 shows how the focus groups and sensory evaluations were performed, u s i ng the two groups of panelists, to optimise the formulation of mutton-based meatballs.

Chopping (3 min) Chopping (4 min) Chopping (5 min)

Kasetsart Focus Group 1 st Ideal Profile Testing

(1 st Trial)

No

Reformulation and Process Alteration

Kasetsart Focus Group 2nd Ideal PrOfile Testing

(2nd Trial)

Yes

Chulalongkorn Focus Group 3rd Ideal Profile Testing

(3rd Trial)

Formulation 1

(a)

Formulation 2

(b)

Yes (with process alteration)

Chulalongkorn Focus Group 4th Ideal Profile Testing

(4th Trial)

PROTOTYPE YES - - - - FORMULATION (b)

(a) formulation 1 : 0.75% white pepper, 0.8% garlic, 0.6% onion, 0.6% ginger (a final formulation from the New Zealand work) .

(b) formulation 2 and prototype formulation : similar to formulation 1 but with 1 .0% garlic and 0.8% onion.

A focus group session was started by sensory evaluation of the meatballs using the ideal profile testi ng (see Section 4.2.3 . 1 ) . Organisation o f the sensory testing fol lowe d the methods described in Section 4.2.3.5. The crumbed meatballs were prepared for serving by deep frying i n soybean oil at 200 ± 5 °C. The sensory characteristics assessed by the participa nts included colo u r, aroma, rubberiness, saltiness, spiciness and o v e rall acceptability. Although the participants were experienced, only a limited number of s ensory attributes were used in sensory evaluation. It was expected that any participant could be at ease in following the procedure and concentrating only on the important attributes.

For t e xtu re , o n ly rubberi n e s s was used si nce it was the most import ant t extu ral characteristic for the meatballs and the results in the early stage of development in New Zealand showed that rubberiness was highly correlated with firmness and smooth ness. Moreover, there were higher correlations between rubberiness and the Instron objective test values than between firmness or smoothness and the same Instron values ( refer to S ection 6.3.1 .8). Oiliness and juiciness were not included since they were not as important as rubberiness, and it was expected that the ideal ratio scores for these two characteristics would not change since the basic formulation , in particular the amounts of fat tissue a nd ice, was exactly the same throughout the tests as the one developed from the New Z e aland work.

For flavour, saltiness and spiciness were included since it was desirable to determin e the responses of the members in the focus groups to these two characteristics. If the products were not close enough to the ideals for these pane lists, who were testing the products for the first time, changes in the levels of salt and spices had to be made. Muttoniness was not included because the panelists might have been biased if they had been told in advance about this characteristic.

The colour of the fried crumbed meatballs, the aroma and the overall acceptability w e re also assessed by the panelists. Scoring for colour, aroma, rubberiness, saltiness and spiciness was done by using the scales shown below. For overall acceptability, scoring was done by using a similar scale to the one shown in Appendix 7.3. Each panelist was asked to locate his or her own ideal on the line scale for each sensory attribute.

Colour

0 5 1 0

extremely not intense colour extremely intense colour

Aroma

0 5 1 0

extremely bad aro ma extremely good aroma

Rubberiness

0 5 1 0

extremely not rubbery extremely rubbery

Saltiness

0 5 1 0

extremely not salty extremely salty

0 5 1 0

extremely not spicy extremely spicy

No training for the sensory ideal profile testing was organised for the panelists. This was due to restriction in time and available resources. The participants in the two focus g roups were experienced people, therefore, it was expected that they could follow the instructions and understand the sensory terms used in the questionnaires clearly. If any problem arose,

it was clarified by the author, as a moderator, to ensure that each panelist fully perceived, in the same manner, what he or she was required to do in the sensory evaluation.

Having finished each ideal profile testing, an open discussion was organised immediately. The panelists still had ideas of the product's eating qualities so they could contribute how the products cou ld be improved or optimised in terms of the sensory characteristics. In addition, some topics related to the products were discussed in order to investigate the aspects which would probably be used in designing a questionnaire for the final con s u mer testing.

The two sessio n s of the Kasetsart focus group were held at the H o me Eco n om ics Department, Kasetsart University and the two sessions of the Chulalongkorn focus g roup at

the Food Technology Department, Chulalongkom University. All sessions were held , in the panel rooms in both departments. Each room was well illuminated with fluorescent lamps and also with good ventilation. The participants evaluated the samples and contribute d their ideas l ater whi l e sitting aro u nd a table. The sensory evaluation sessions started at approxi mately 2 .30 p.m.. The discussion session, moderated by the author, was tape recorded and it took approximately between a half and three quarters of an hour to complete it.

8.4 RESULTS AND DISCUSSION

8.4.1 of the Ideal Profiles

The ideal profiles, as represented by the mean ideal absolute scores, of the s ensory attributes of the mutton-based meatballs given by the two focus groups are given in Table 8.1 .

Table 8.1 The ideal profiles of the sensory attributes of the mutton-based meatballs by the two focus groups ( 1 )

Attribute Colour Aroma Rubberiness Saltiness Spiciness

Mean Ideal Absolute Score

Kasetsart Focus Group Chulalongkorn Focus G roup

( 1 st Trial) (3rd Trial) 6.4 8.1 6.7 6.0 6.6 5.8 9.3 7.5 5.7 6.3

( 1 ) These values were used as the 'fixed' ideals for the subsequent ideal profile testings ;

i . e . in the 2nd trial for the Kasetsa rt focus g roup and in t h e 4th t ri a l fo r the Chulalongkom focus group.

The mean scores for 'ideal' saltiness and spiciness as perceived by the two focus groups were close; the difference being 0.3. In general, the members of both groups wanted the ideal meatballs to be salty and relatively spicy. Colou r was another attribute which should be slightly intense in the perceptions of the members of both gro ups. However, the ideal aroma score should be high, over 8.0 for the Kasetsart focus group and even over 9.0 for the Chulalongkorn focus group. The ideal meatballs should also be relatively rubbery for both groups, but the Chulalongkorn focus group preferred the more rubbery product ; the difference being O.S.

8.4.2 of Attributes the Focus

The mean ideal ratio scores (the product's score : the ideal absolute score) of the sensory characteristics of the meatballs, for all fou r sensory ideal p rofile testings (trials) , were calculated and then used in plotting the ideal ratio scores for the four products. This is shown numerically in Table 8.2 and illustrated graphically in Figure 8.2.

Table 8.2 Mean ideal ratio scores of the sensory attributes of the meatballs tested in a sequence of focus groups ( 1 )

Kasetsart Focus Group Chulalongkorn Focus Group

Sensory 1 st Trial 2nd Trial 3rd Trial 4th Trial

Attribute Colour 1 .20 ± 0.03 1 . 1 2 ± 0.09 1 .28 ± 0.07 1 . 1 1 ± 0.01 Aroma 0.69 ± 0.04 0.84 ± 0.1 0 0.86 ± 0.05 0.96 ± 0.02 Rubberiness 0.82 ± 0.05 0.92 ± 0.06 0 .62 ± 0 .07 0 .88 ± 0 .03 Saltiness 0.96 ± 0.09 0.99 ± 0.02 0.92 ± 0.08 0.98 ± 0.03 Spiciness 0.78 ± 0. 1 8 0.84 ± 0.09 0.94 ± 0.06 0.94 ± 0 .02 Overall 0.67 ± 0.07 0.87 ± 0.07 0.77 ± 0.05 0.94 ± 0 .01 Acceptability

r u b b e r i n e s s 8 r o m a

S 8 l t i ne s s c o l o u r

s p i c i n e s s o ve r a l l a c c e p t a b i l i t y

Key: __ Ideal ( 1 .0)

Figure 8.2

Kasetsart focus group, 1 st trial (0.75% white pepper, 0.8% garlic, 0 .6% o nion , 0.6% ginger, 3 min chopping)

Kasetsart focus group, 2nd trial (0.75% white pepper, 1 .0% garlic, 0.8% o nion, 0.6% ginger, 4 min chopping)

Chulalongkorn focus group, 3rd trial (same as 2nd trial)

Chulalongkorn focus group, 4th trial (same as 2nd and 3rd trials, 5 min chopping�

Profiles of the ideal ratio scores of the sensory attributes of the m e atballs tested in a sequence of focus groups

The results showed the Kasetsart focus group was not satisfied· with the sensory attributes of the meatballs in the first trial. The colour score was too high, and the aroma, spiciness and overall acceptability scores were too low. Rubberiness score was relatively high and saltiness was almost perfect.

From the sensory evaluation results and the ideas contributed by the participants in t h e first trial, all partiCipants agreed that the meatballs were acceptable. However, they thought the

sensory characteristics could be improved. For flavour and aroma, they suggested that no other types of spices could be used. They said that hotness of the product was just right, therefore no more white pepper could be used especially if the product would be consumed by children. Most panelists suggested that higher amounts of garlic and onion could be used to improve the flavour and aroma.

Since saltiness of the meatballs was just right, it was expected that changing of the salt level could not be made. The levels of tapioca starch and STPP were also kept con st ant. It was shown that salt had the more pronounced effect on the texture of the meatballs. Therefore , alt eration of the levels of the other two ing redients w as not expected to substantially i mprove the textural characteristics of the meatballs. I nstead, i t was anticipated that the chopping time had to be increased. A little longer chopping time might help in comminuting the meats to a greater extent, thus resulting in more extracte d salt soluble proteins which functioned in binding of meat particles. As a result, this might improve rubberiness.

Therefore , the amount of garlic was increased to 1 % and that of onio n to 0.8%. The chopping time was increased from 3 minutes to 4 minutes. The meatballs made by u sing the altered formulation and chopping time were tested again with the same focus g roup in the second trial. It was shown that the scores for aroma and overall acceptability were very much higher and those for rubberiness and spiciness were also increased. Increasing both garl ic and o n io n contents and altering t h e chopping t i m e i m p roved all s e n so ry characteristics.

This newly optimised formulation was retested with the Chulalongkorn focus gro u p in the third trial. The products were acceptable to the partiCipants for aroma, saltine s s and spicin ess. The co lour was too intense and the rubberiness score was too low . The panelists in this focus group preferred the 'ideal' product to be more rubbery than the 'ideal' product as regarded by the membe rs in the Kasetsart focus group (refer to Table 8 . 1 ) . Therefore, they perceived and commented that the meatballs were not rubbery enough. To increase rubberiness, the chopping time was, therefore, raised to 5 minutes.

The meatballs made by using the same formulation but with the altered chopping ti m e was tested again. The results from this fourth trial showed that all sensory attribute scores were very good; four of the six characteristics having the ideal ratio scores within 0.06 of 1 .0 and the rubberiness score being at 0.88.

8 .4.3 Ideas from the Kasetsart Focus

Most pane lists agreed t hat the colour of the fried crumbed meatballs was too intense but they commented that this defect was not critical since it was rather related to the degree of doneness which might be differently liked by each individual.

For spiciness, the panelists drew the conclusion that no other types of spices should be used to improve flavour and aroma. A few panelists thought that coriander roots, which are commonly used in Thai foods especially meat dishes, would create further problem s such as 'not-smooth' p rod ucts if t h e roots had not been finely g ro u nd and additional microbiological load if the roots had not been hygienically cleaned.

Cru mbing helped differentiate the product from local meatballs and gave the image of co nvenience food . It also improved the textu re of the pro duct s ince the pa n elists experienced something crispy during mastication and it helped conceal the unfamiliar meaty aroma. In addition, the crumbs gave good aroma to the meatballs.

The p anelists indicated that fry ing was the most appropriate cooking method for the crumbed meatballs. However, if the meatballs were not crumbed , they could be prepared by boiling with soup stock, stir-frying with vegetables, charcoaling, and making into salad. The product could be consumed directly with cooked rice in any meals , breakfast, lunch, dinner, or as snacks.

Some ideas related to marketing of the product were also contributed by the participants. Having been informed that the price of the product wou ld be higher than the prices of local meatballs, the pane lists suggested that the meatballs be packed in retail-size package s with approximately 8-1 0 balls per pack so that the total price per pack should not be too h igh for ordinary consumers. All pane lists mentioned that the product ought to be packed in a well­ designed package with transparent plastiC film covering one side of the package and there ought to be a lab e l on the p ackage. The p laces su itable a s retail outlets were supermarkets. The product could be placed beside sausages in refrigerators. One p anelist said that the product could be placed for sale in fresh markets as well.

The panelists wanted to have on the label the name and address of the manufacturer; the ingredients a nd additives, if any, and t heir percentages ; net weight ; expiry date and methods of use. Only one pane list mentioned about the emblem o n the packages . This e mble m is issu ed by the Food and Drug Administration, M i n istry of Public H e alth. Acco rding to the Thai Food regu l ations, o nly 'co ntrolled foods' should require such emblems. However, meatballs are not specified as controlled foods at the present tim e .

The name 'New Zealand meatballs' was considered appropriate if the product would be aimed for sale in the supermarkets because it would reflect the product's uniqueness . On the other hand, a few panelists commented that 'New Zealand' would possibly imply t h at the product was made of sheep meats. Therefore, in their opinion, it might not be suit able to use 'New Zealand' in the name of this product. A few pane lists suggested if there was the indication that the product was fro m an overseas country, it might be more attract ive to consumers than Thai names.

The pane lists suggested that advertising p lanning and campa igning should b e well performed to promote the product. Most panelists thought that advertising in television was