• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.351-357
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• 2001

The rapid formation of a cream line cannot be observed in raw goat's milk standing at a low temperature. Although the poor creaming ability of goat's milk has been considered to be due to the small size of milk fat globules and the lack of euglobulin capable of being adsorbed on milk fat globules, there is much left to study. The present work attempted to elucidate a factor for poor creaming ability of goat's milk. The creaming ability of the experimental milks reconstituted from creams and skim milks separated from cow's milk or goat's milk was measured by the volume of the cream layer and the fat content of bottom layer. The polypeptides composition of the P1 the fraction (i.e., the high molecular weight fraction eluted near the void volume obtained by the gel filtration of whey) and milk fat globule membrane prepared from both milks were compared. It was found that the promotion of creaming originated from goat's skim milk was lower than that from cow's skim milk. The P1 fraction in goat's skim milk was less than that in cow's skim milk. The polypeptide (M.W. $4.3{\times}10^4$), found in the P1 fraction of cow's milk was not found in the P1 fraction of goat's milk. It is suggested that the poor creaming ability of goat milk is caused mainly by the difference from cow milk in the amount and the composition of the P1 fraction.

• Journal of Dairy Science and Biotechnology
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• v.31 no.2
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• pp.93-98
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• 2013

For purposes of substantiation of organizing measures on industrial processing of goat's and sheep's milk in Mongolia and the production of dairy products we have conducted the studied physico-chemical characteristics of the Mongolian goat's and sheep's milks especially to recognize amino acids, minerals and vitamins in the milk and compare with the Mongolian cow's milk. And also was studied fractional structure of goat's milk whey proteins.

• Journal of Animal Science and Technology
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• v.47 no.1
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• pp.83-90
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• 2005

ACE-inhibitory peptides derived from goat's whey hydrolyzed by various proteolytic enzymes were separated and purified for antihypertension materials. The highest ACE-inhibitory activity of goat's whey hydrolysates was 85.5 % by pepsin for 72 hrs. Also the highest ACE-inhibitory activity of goat's whey hydrolysates was F-4 by pepsin for 72 hrs by Sephadex G-25 gel chromatograms. F-4e and F-4ed from F-4 by RP-HPLC to first and second purification were the highest in ACE-inhibitory activity, respectively. The most abundant amino acid was leucine(I 8.54 %) in F-4ed of ACE-inhibitory peptides after second purification. Amino acid sequence of F-4ed of ACE-inhibitory peptides showed Leu-Lys-Asp-Tyr-Gly-GlyVal- Ser-Leu and Leu-Gly-Asp-Gly-Ala-Gly- Asp-Val-Ala-Phe. $IC_{50}$ calibrated in peptic hydrolysates(72 hrs), F-4, F-4e and F-4ed from goat's whey hydrolysates by pepsin for 72 hrs were 33.93, 28.75, 11.74 and 1.09 mg/ml, respectively. From the results of this experiment, goat's whey hydrolysate by pepsin was shown to have ACE-inhibitory activity.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1513-1513
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• 2001

Present Food Legislation compels dairy industry to carry out analyses in order to guarantee the food safety and quality of products. Furthermore, in many cases industry pays milk according to bacteriological or/and nutritional quality. In order to do these analyses, several expensive instruments are needed (Milkoscan, Fossomatic, Bactoscan). NIRS technology Provides a unique instrument to deal with all analytical requirements. It offers as main advantages its speed and, specially, its versatility, since not only allows determine all the parameters required in milk analysis, but also allows analyse other dairy products, like cheese or whey. The objective of this study is to develop NIRS calibration equations to predict several quality parameters in goat milk, cheese and whey. Three sets of 123 milk samples, 190 cheese samples and 109 whey samples, have been analysed in a FOSS NIR Systems 6500 I spectrophotometer equipped with a spinning module. Milk and whey were analysed by folded transmission, using circular cells with gold surface and pathlength of 0.1 m, while intact cheese was analysed by reflectance using standard circular cells. NIRS calibrations were obtained for the prediction of chemical composition in goat milk, for fat (r$^2$=0.92; SECV=0.20%), total solids (r$^2$=0.95: SECV=0.22%), protein (r$^2$=0.94; SECV=0.07%), casein (r$^2$=0.93; SECV=0.07%) and lactose (r$^2$=0.89; SECV=0.05%). Moreover, equations have been performed to determine somatic cells (r$^2$=0.81; SECV=276.89%) and total bacteria (r$^2$=0.58; SECV=499.32%) counts in goat milk. In the case of cheese, calibrations were obtained for the prediction of fat (r$^2$=0.92; SECV=0.57), total solids (r$^2$=0.80; SECV=0.92%) and protein (r$^2$=0.70; SECV=0.63%). In whey, fat (r$^2$=0.66; SECV=0.08%), total solids (r$^2$=0.67; SECV=0.19%) and protein (r$^2$=0.76; SECV=0.07%) NIRS equations were obtained. These results proved the viability of NIRS technology to predict chemical and microbiological parameters and somatic cells count in goat milk, as well as chemical composition of goat cheese and whey.

• Food Science of Animal Resources
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• v.42 no.5
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• pp.800-815
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• 2022

This study aimed to obtain high Fischer's ratio oligopeptides from goat whey (HFO) and investigate antioxidant property of it. Hydrolysis of goat whey was done with the approach of sequential digestion of pepsin and flavourzyme. With the adsorption of aromatic amino acids by activated carbon, HFO with a Fischer's ratio of 27.070 and a molecular weight of 200-1,000 Da were obtained, and the branched-chain amino acids accounted for 22.87%. Then the antioxidant activity of HFO was evaluated. At the concentrations of 2.0 mg/mL and 0.50 mg/mL, HFO scavenged 77.27% and 99.63% of 1,1-diphenyl-2-picrylhydrazyl and 3-ethylbenzthiazoline-6-sulphonate free radicals respectively. The scavenging rate of HFO against hydroxyl radicals reached 92.31% at the concentration of 0.25 mg/mL. Animal experiments demonstrated that HFO could moderate the changes of malondialdehyde, superoxide dismutase and glutathione peroxidase caused by CCl₄-induced oxidative stress in vivo. This study indicated that HFO from goat whey was capable of oxidation resistance both in vivo and in vitro, which provided a scientific basis for the high-value processing and application of goat milk whey.

• Food Science of Animal Resources
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• v.42 no.2
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• pp.210-224
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• 2022

The use of skim milk is a strategy to increase goat milk yogurt acceptability. However, it can negatively affect yogurt rheology because fat plays a vital role in dairy structural integrity. Thus, this study aimed to investigate the effects of fat replacers on the rheological, physical, and sensory parameters of low-fat cupuassu goat milk yogurts during refrigerated storage (28 days). Five goat milk yogurts formulations were carried out: whole yogurt (WY), skim yogurt (SY), skim yogurt with inulin (SIY), skim yogurt with maltodextrin (SMY), and skim yogurt with whey protein (SWY). Treatments were subjected to bacterial counts, chemical composition, pH, water holding capacity, instrumental color and texture, rheological and sensory analyses. All samples showed reducing pH values, water holding capacity, and L^* and b^* value during storage. Regarding texture, the firmness and consistency decreased during storage. On the other hand, the viscosity index significantly increased during refrigerated storage time. Moreover, all treatments exhibited viscoelastic behaviour. In addition, SIY and SMY showed the highest apparent viscosity. Furthermore, SIY, SMY, and SWY formulations exhibited positive sensory scores for appearance, color, aroma, texture, and viscosity. However, the overall acceptability and purchase intention did not differ statistically between WY and the fat-replacement treatments (SIY, SMY, and SWY). These results indicate that fat substitutes improved the quality of skimmed formulations. Thus, inulin and maltodextrin have the potential as functional fat replaces to produce low-fat goat milk yogurts.

• Food Science of Animal Resources
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• v.40 no.5
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• pp.689-698
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• 2020

The aim of study was to scrutinize the physicochemical and protein profile of milk obtained from local Pakistani breeds of milch animals such as Nilli-Ravi buffalo, Sahiwal cow, Kajli sheep, Beetal goat and Brela camel. Physicochemical analysis unveiled maximum number of total solids and protein found in sheep and minimum in camel. Buffalo milk contains the highest level of fat (7.45%) while camel milk contains minimum (1.94%). Ash was found maximum in buffalo (0.81%) and sheep (0.80%) while minimum in cow's milk (0.71%). Casein and whey proteins were separated by subjecting milk to isoelectric pH and then analyzed through sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The results showed heterogeneity among these species. Different fractions including α_S1, α_S2, κ-casein, β-casein and β-lactoglobulen (β-Lg) were identified and quantitatively compared in all milk samples. Additionally, this electrophoretic method after examining the number and strength of different protein bands (α_S1, α_S2, β-CN, α-LAC, BSA, and β-Lg, etc.), was helpful to understand the properties of milk for different processing purposes and could be successfully applied in dairy industry. Results revealed that camel milk was best suitable for producing allergen free milk protein products. Furthermore, based on the variability of milk proteins, it is suggested to clarify the phylogenetic relationships between different cattle breeds and to gather the necessary data to preserve the genetic fund and biodiversity of the local breeds. Thus, the study of milk protein from different breed and species has a wide range of scope in producing diverse protein based dairy products like cheese.