This study investigated the seasonal effect on composition, somatic cell content and coagulationproperties of bovine milk during two different periods of the year (summer and autumn). 592 samples of raw milk from Italian Holstein-Friesian cows from different locations in the Veneto region, Italy, were collected. The samples were submitted to the following analyses: fat, protein, casein and lactose percentages and pH by infrared spectroscopy; somatic cell counting by optical fluorescence and milkcoagulationproperties expressed in rennet coagulation time (RCT, min) and curd firmness or consistency 30 minutes after the addition of rennet (a 30 , mm) by lactodinamography. The index of the aptitude of milk to coagulate (IAC) was also determined from the lactodinamographic parameters that were obtained. To verify the environmental conditions, the temperature humidity index (THI) was calculated for each collection period. No significant difference (p <0.05) was observed between protein, casein, lactose and pH in the samples collected in the summer and the autumn. However, the results for somatic cells, RCT, a 30 and IAC were significantly different, with lower results in the summer. Over all the total samples analysed, 41.2% showed a milk that did not coagulate in the 30 minutes, with a higher percentage for samples collected in the summer and during this period presented lower results to of RCT, a 30 and IAC; the THI values, as expected, were higher in the summer than in the autumn. The THI presented statistically different means (p <0.05), which were 73.24 in the summer and 57.43 in the autumn. Milk with this characteristic is not suitable for cheese production; however, it is suitable to produce fluid milk, or for other derivatives where enzymatic coagulation is not part of the process.
Background: In the last years, difficulties occurring in corn cultivation (i.e., groundwater shortages, mycotoxin contamination) have been forcing dairy farmers to consider alternative silages. Some experiments conducted on lactating cows have proven that the total replacement of corn silage with sorghum silage did not reduce milk yield. However, this kind of substitution involves supplementing sorghum-based diets with grains, to compensate for the lower starch content of sorghum silage compared to corn silage. Change of silage type and inclusion of starch sources in the diet would influence rumen fermentations, with possible effects on milk composition (i.e., fatty acid profile) and coagulationproperties. A worsening of milkcoagulationproperties would have a negative economic impact in Italy, where most of the milk produced is processed into cheese.
ABSTRACT: The aim of this study was to determine the joint effects of CSN3 and LGB genotypes on parameters of production, quality and coagulation of milk in Czech Fleckvieh cows. Three hundred and twenty-eight Czech Fleckvieh cows were determined for CSN3 (kappa-casein) and LGB (beta-lactoglobulin) genotypes using the PCR-RFLP method, milk quality parameters and coagulationproperties. Milk production parameters were obtained from the Official Database of Progeny Testing. Fifteen genotype combinations were detected, with ABAB (21.0%) and AAAB (18.3%) occurring as the most frequent. The observed genes significantly affected the contents of milk protein (crude protein, true protein, casein and whey protein) as well as solid non-fat in milk, casein number and curd quality. BBAA was found to be the genotype with the highest positive impact on most of the milk characteristics evaluated. Whereas ABBB, BBBB, BBAB and ABAB had a positive influence on milk quality and milkcoagulationproperties, genotypes containing CSN3 allele E had a negative effect. Results presented in this study are applicable in the selection of Czech Fleckvieh cattle.
observations of these shapes under different magnifications (8000 x, 6000 x, 3500 x, 500 x, 10000 x). These varying shapes are due to the different surface properties of the biomaterials. The contact angle of O-C 53 Fig. 7D under 500 x was 200 µM in diameter. Because O-C 53 is a powder, observation at a higher magnification was ineffective because the beam could not readily penetrate the sample to detect platelet contact with the desired crossover diameter and failed to form an acceptable image. Platelets were defective and did not display any granulation. All the aggregated platelets had already discharged their granules, shown in Fig. 7A-7C. No single platelets were observed. All the platelets coagulated to form a large group, forming a fibrin clot that reinforced platelet aggregation. Our results were positive compared to those of the Lyostypt, which was made up of highly flexible strands that allowed platelets to form fibrin networks Fig. 7E.
Influence of CaCl 2 dose. The procedure for the prepa- ration was slightly different because each sample of milk was now adjusted separately. Milk was adjusted using the following additions of 0.2M solution of CaCl 2 : 20 ml of CaCl 2 + 980 ml of milk, 30 ml + 970 ml, 40 ml + 960 ml, 50 ml + 950 ml, 60 ml + 940 ml, 70 ml + 930 ml). 250ml samples of adjusted were prepared (i.e. 5, 7.5; 10; 12.5; 15; 17.5 ml of CaCl 2 which were made up with milk to the total volume of 250 ml). The samples were warmed to and kept at the tem- perature of 31°C. To each, conditioned sample of 250 ml volume in the beaker, 12.5 ml of 1% rennet solution was added (basic dose of 50 ml per 1000 ml of adjusted milk). The frequency of oscillation was set to 1 Hz, the relative deformation to 3.2%. The masurement was performed three times and the average value was calculated. Between the individual measurements, the time step of 1 min was se- lected.
The camel’s milk is used to inhibit some cases of cancer, such as lung, breast, and colon (Korashy et al., 2012; Habib et al., 2013). Some studies have found that camel’s milk could prevent the formation of new blood vessels resulting from inflammation. It also has fatal effects on liver cancer cells by blocking the gene expression of one of the enzymes needed to activate carcinogens (Korashy et al., 2012). None of the compounds responsible for cancer resistance in the camel’s milk has been identified to date. However, lactoferrin has been found to have significant effects (Habib et al., 2013). It has been shown to give cancer patients with chemotherapy better results than chemotherapy alone and has had inhibitory growth effects colon and rectum cancer in humans (Habib et al., 2013). In addition, it found to have toxic effects of cancer cells by preventing growth, reproduction, and stimulate death.
Enzymatic hydrolysates of cow milk proteins possessing low allergenic potential and high nutritional value are added into the special infant, sport, and dietetic food formulas (Clemente, 2000; El-Agamy, 2007; Tsabouri et al., 2014). Moreover, fermented dairy products (yogurt, kefir, sour cream, cheese) have a long application record as traditional ingredients of daily alimentary diet (Tamime, 2002). Beneficial physiological effect of protein hydrolysates and fermented foods is achieved by better digestion of peptides in gastrointestinal tract compared with native proteins and amino acids. It is also determined by a broad spectrum of biologically active properties (Schaafsma, 2009; Raikos and Dassios, 2013; Sánchez and Vázquez, 2017).
It is difficult to draw conclusions from the capillary electrophoresis data. When compared to reference values (Ng-Kwai-Hang, 2002), it is apparent that protein losses have occurred in most samples. The sample preparation or CE analysis may have caused low recoveries. It is possible that samples were not adequately reconstituted, resulting in low protein concentration. Another possibility may be that the 6M urea sample buffer was not concentrated enough to solubilise all of the protein in the reconstituted sample. In raw milk, for which Heck et al. (2008) developed the method, no difficulties in protein separation by CE were experienced. Because of time constraints in this study, the validity of this method for testing reconstituted milk powder was assumed and not fully established before use. However, the process of drying alters milk chemistry, making milk powder vastly different from fresh milk. Thermal denaturation of whey proteins takes place and disulphide bonding with κ- casein occurs. It is more than likely that these enhanced protein-protein interactions interfered with separation and that higher amounts of urea are required for complete protein solubilisation and determination in milk powder.Consequently the results of CE in this study were were inconclusive and uninformative.
71 milk casein hydrolysate increased Con A induced IL-2 and IFNγ production in spleen cells. Our findings clearly indicate that digestion products (fermented or unfermented) act on the cytokine network, as illustrated by IFNγ and IL-2. Comparison of IFNγ and IL-2 production with the proliferation response of lymphocytes indicated evidence of parallelism. Cytokine production (Fig. 5.4 and 5.5) and proliferation response (Fig. 5.1) were maximal at 0.125 mg/mL protein concentration. There was no significant difference (P > 0.05) compared to control at higher concentration of proteins. Similarly using Con A stimulated human PBMC, Laffineur et al., (1996) reported Lactobacillus helveticus 5089 fermented cow milk to have the highest IFNγ and IL-2 productions at protein concentrations of 19 and 9 µg/ml, respectively, and the production of the cytokines was decreased with increasing protein concentration. IFNγ is a typical type 1 helper T cytokine, which enhances immune response. Matsuzaki, (1998) showed that Lactobacillus casei strain Shirota had a potent anti-tumour effect on transplanTable tumour cells by inducing production of several cytokines including IFNγ, resulting in the inhibition of tumour growth. IFNγ production has been considered as a key factor for anti-tumour activity of mushroom bioactives (Xu et al., 2011). Blattman et al., (2003) reported that the specific interaction of casein hydrolysates with IL-2 might prove useful in modulating dysregulated immune responses as well in the treatment of various immune processes such as chronic viral infections. Our finding suggests deer milk digests and digests of LAB fermentation can enhance Con A stimulated IL-2 and IFNγ secretion, which would potentially amplify a lymphocyte (T cell) mediated response and differentiate helper T cells into Th1 cells. Therefore, these immunomodulatory deer milk digests (unfermented and fermented) could serve as a potential immunotherapeutic agent by selectively increasing the pool of activated T lymphocytes.
During the continuous coagulation process, samples of flocs were taken from rapid mixer, the third flocculation basin and sedimentation tank using a tube with an inner diameter of 5 mm every ten minutes . Floc size distribution (FSD) was measured by Mastersizer 2000 (Malvern, UK) and each sample was measured thirds times and obtained the average results. During the slow mixing period in the third flocculation basin, zeta potential was measured by zetasizer Nano ZS (Malvern, UK). The images of flocs from rapid mixer, the third flocculation basin and sedimentation tank were captured by IX71 digital photomicrography (Olympus, Japan).
equation (1). Third measured rheologic parameter – ﬂ uidity had increasing exponential shape. Mathematical description of the dependencies are summarised as regression equations 2–4 and by regression and determination coeﬃ cients presented in the tables. Eﬀ ect of storage was analyzed and the results are shown in the paper. Dynamic and kinematic viscosities of milk were a bit higher a er storing due to the loosening of the water during the storage and for same reasons were milk ﬂ uidities higher a er the storing. In all measurements were dynamic viscosities of acidophilus milk lower than at the beginning of storage and that can be caused by structural changes in the sample during the storage. Based on the presented facts of the research results are: Hot wire method is very convenient for measuring of thermophysical parameters of liquid and suspensoid food materials. For detection of selected rheologic parameters is very useful single – spindle viscometer. The research results detected inﬂ uence of temperature, fat content and storing time to the physical properties of milk and acidophilus milk.
β-lactoglobulin is the major milk whey protein in the ruminants. Studies have indicated that this protein is polymorphic in the many breeds of sheep. This is the result of a single base pair substitution in the β-lactoglobulin gene. The genetic variants, A (tyrosine) and B (histidine), differ at the amino acid position 20. The nucleotide mutation disrupts an RsaI site and can be detected by PCR-RFLP analyses. We included in this study 52 animals from Karakul breed. The Karakul may be the oldest breed of domesticated sheep. In Romania it is raised especially for pelts. The aim of this work was to analyze the genotype distribution of β- lactoglobulin in Karakul sheep.
In the second study, it was established how the proteins were affected during heating by determining changes at 75, 85, 95, 100, or 110ºC and prolonged heating of 2.6 minutes at 121ºC. All three concentration level (9, 17 and 25% TS) were examined. Treated samples were analysed for changes in the particle diameter, zeta potential, changes in protein level between the serum and colloidal phase, protein rearrangement in the secondary structure and variations in the mineral content (calcium, magnesium, phosphate and sodium) between the serum and micellar state. According to the results applied temperature induced formation of aggregates, which intensity was dependant of concentration level. Moreover, whey proteins denaturation was delayed in increased solids contented, which moved to higher temperatures as TS increased. However, after reaching specific temperature they were involved in intense aggregation among themselves through thiol-sulfhydryl interchange reactions and with caseins by disulfide interactions forming particles with larger diameter. In skim milk with 9% TS this delay of denaturation of milk proteins was not present and aggregation resulted only in more soluble particles which did not affect the average size distribution. Other important detail was large variations in the casein level in the serum, thus involving intense dissociation of specific caseins at certain temperatures. Observed changes were supported with rearrangement of the secondary structure of the micelle that was variable in regards to concentration level and applied temperature.
formation of the lactic acid from lactose by the lactic bacteria, is firstly buffered . L-Lactic acid is a critical parameter in the production of milk and milk products, confirming the degree of freshness in milk and determines the taste and aromas in fermented products such as yogurt. Changes in acidity appear also during thermal treatment. Heating causes the loss of carbon dioxide, can break down the lactose into various organic acids or cause blockage of amino groups of proteins and then causes an increase in acidity. At high temperature, the tricalcium phosphate may precipitate and cause an increase in acidity triggered by dissociation of the phosphate radicals. The two common ways to measure acidity are pH and titratable acidity (TA). pH measures the concentration of disassociated hydrogen ions in the solution, and titratable acidity measures the concentration of both disassociated and un- disassociated hydrogen ions. TA measures all the acid in solution, both molecules that have given up their protons and those that have not.
subsp. lactis, Leuconostoc mesenteroide, Lactobacillus casei subsp. casei, Lactobacillus casei. Lactobacillus kefiri, Lactobacillus curvatus, Lactobacillus sakei have been isolated from fresh camel bulk milk of both the species (Camelus dromedarius and Camelus bactrianus) and, also, from the sample of ‘Shubat’ (Akhmetsadykova et al., 2015). Hamed and Elattar (2013) had isolated several lactic acid bacteria from raw camel milk obtained from Arabian Camels of Egypt. They determined one isolate Lactobacillus plantarum, Lactococcus lactis, Enterococcus durans, Aerococcus viridians and, in addition, isolated seven isolates of Enterococcus faecium. Benkerroum et al. (2003) and Jans et al. (2012) also exhibited the predominance of Enterococci, especially Enterococcus faecalis, in camel milk microflora in Morocco and in Kenya respectively. From raw camel milk, isolated lactic acid bacteria like Lactobacillus fermentum and Lactobacillus plantarum showed probiotic potential like absence of undesirable properties (Mahmoudi et al., 2016). In their study, Khedid et al. (2009) identified and isolated a variety of bacteria from raw camel milk derived from Morocco, including species such as Lactobacillus helveticus (10%), Lactococcus lactis subsp. lactis (17.5%), Lactobacillus casei subsp. casei (5.80%), Streptococcus salivarius subsp. thermophilus (9.20%) and Lactobacillus plantarum (5%). Same authors (Khedid et al., 2009) also isolated Lactobacillus amylophilus from camel milk which was already proved as a beneficial strain in the fermentation of crude starch to lactic acid and has a lot of applications in food industries (Naveena et al., 2004). In a recent study, probiotic Lactobacillus strains (Lb. reuteri-KX881777, Lb. plantarum-KX881772, Lb. plantarum-KX881779) isolated from camel milk found more promising rather than the other non-camel milk strain (Lb. plantarum DSM2468), during the comparative study (Ayyash et al., 2017).
Clinical nutrition products are specifically formulated nutrients to help people manage various health condi- tions. With recent advances in biotechnology, new tech- niques and tools are now available to isolate components from food that have additional health enhancing properties. Peptides are good candidates for advanced clinical nutrition and supplements since they are easily absorbed, and unlike many plant based com- pounds, peptides are amino acids that can be eliminated naturally by the body with less potential toxicity . We have isolated a peptide mixture from regular cow’s milk that preliminary basic and clinical research indicates may have some beneficial bioactive properties. The pur- pose of this study was to: (1) characterize the molecular
Observing a neutral presence of ginseng extracts in the probiotic milk medium is an interesting finding. Previous research suggests that ginseng has antioxidant constitu- ents as well as antimicrobial properties against various strains of pathogenic bacteria, thus it would be reason- able to expect reduced probiotic viability [1-3,35]. To our knowledge, no data to support or contradict these findings was present in the literature. However, research has been conducted to investigate the effects of adding herbal compounds with antioxidant and antimicrobial properties on probiotic viability within milk products. Beheshtipour and colleagues  added microalgae spe- cies Chlorella vulgaris or Arthrospira platensis to yogurt containing probiotic strains Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12. They observed similar antioxidant activity between probiotic yogurts with and without microalgae, and increased viability of both probiotic species containing either C. vulgaris or A. platensis at each measurement point over the 28-days refrigerated storage period. Haddadin  combined ei- ther aqueous or alcoholic olive leaf extracts with skim milk containing Bifidobacterium infantis and Lactoba- cillus acidophilus (strains unspecified). Increased viabil- ity of both probiotic strains were observed after 16 h in- cubation period for olive extract concentrations below 3.0 mg Catechin Equivalents/mL, whereas adding 5.0 mg Catechin Equivalents/mL resulted in significantly de- creased probiotic viability. The concentration at which olive oil inhibited microbial growth was greater than a previous study where 2 mL of olive oil exerted bacteri- cidal activity against probiotic microorganisms such as L. acidophilus and Bifidobacterium bifidum when placed in bactericidal activity assay . An additional study mixed
The apparent colloidal stability of breadfruit-corn milk was higher than that of soymilk (Fig.1) during the 72 h observation. The slower decline in apparent colloidal stability of breadfruit-corn milk as compared to the soymilk could be an indication of more uniform dispersion of solutes and gradual deterioration during storage. This could be attributed to the nature of protein complexes in the beverage types. Formation of hydrophilic protein-lipid complexes has been implicated in soymilk colloidal stability (Nelson et al., 1976). Hosney et al. (1994) associated glutamic acid with corn proteins. Since glutamic acid is hydrophilic in nature (Nelson et al., 1976), better apparent colloidal stability of corn milk and breadfruit-corn milk could be attributed to stronger hydrophilic protein-lipid complexes in the corn based beverages. Also, the higher occurrence of starch in the corn based beverages due to higher carbohydrate content, with resultant gelation of starch under heat might have contributed to their higher apparent colloidal stability. Weak colloidal stability is one setback for vegetable milk that requires consistent studies to evolve the right combinations of emulsifiers and stabilizers that most suit particular milk extract or their blends. The foam stability of milk samples after 1 min, 10 min, 60 min and 90 min after whip is as shown in Fig.2. It can be seen that all through the 90 min observation, the breadfruit-corn milk had the least stable foam of less than 0.2 ml. The soymilk had the highest foam stability, with a peak value of 4.5 ml after 1 min, maintaining the lead until 90 min when it ended at 1.3 ml behind the corn milk sample which recorded 1.6 ml. The high value of the soybean and sweet corn extracts which might be attributed to the prevalent oligosaccharides and their behavior when subjected to certain processes. Onyesom et al. (2005) stated that a process which increases soluble sugars reduces emulsion and foam stability. Parades-Lopez et al. (1991) reported that foam stability is important because whipping agents depends on its ability to maintain the whip as long as possible.