Characterization of yogurt goat milk added Aloe vera and Stevia rebaudiana with functional potential

The search for functional foods with health benefits has increased,and yogurt represents one of these products due to their properties,such as,source of probiotics that favour the gastrointestinal system,contains vitamins,minerals and improves the action of enzymes.Present work investigated bromatological,microbiological,sensorial properties and shelf-life of different yogurt goat milk formulations with Aloe vera and natural sweeteners.The goat yogurt with 99.40%A.vera pulp and 0.60%S.rebaudiana presented the best nutritional composition,being suitable for human consumption representing an innovative product with a great functional potential.The synergy between the ingredients used in the yogurt processing resulted in an innovative product to the market.Goat milk has a lower cost per liter in comparison with cow milk,Aloe vera is accessible due to its fast-vegetative propagation,Stevia Rebaudiana has a great popularity for being a natural sweetener with no calories,and all these products are produced in México.

Fluorescence-based PCR Detection of Goat Milk Powder Mixed with Cow Milk

[Objectives]To amplify and identify the specific gene fragments of cattle and sheep by real-time fluorescence-based PCR,and quickly and accurately identify the adulteration problem of goat milk powder according to the differences of mitochondrial genes among different species.[Methods]The specificity,limit of detection and repeatability test were carried out by isolating somatic cells,extracting template DNA and determining the reaction conditions of real-time fluorescence-based PCR.[Results]The real-time fluorescence-based PCR method could be used to identify the bovine and ovine-derived materials of milk powder with high specificity,high sensitivity and good repeatability,and the limit of detection of milk components in goat milk powder could reach 0.01%.[Conclusions]The real-time fluorescence-based PCR method can be used to quickly and accurately detect the milk components in goat milk powder,and provide some technical support for the adulteration detection of dairy industry.

Handling and Hygienic Production Practices of Goat Milk in Degahbur District of Jarar Zone, Somali Regional State, Ethiopia

A cross-sectional study was carried out to assess handling and hygienic production practices of goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 120 households were purposively selected for this study using a stratified sampling technique. The data were collected through the questionnaire, field observations, key informants interview and focus group discussions. The study showed that majority of the sampled households were illiterate. The goats were kept in an open kraal made of thorny acacia trees on an earthen floor that had no roof. The goats were milked inside these open kraals, and were sometimes contaminated with muck and animal dung mainly the rainy season which could raise the possibility of milk contamination & spoilage. Moreover, traditional hand milking was the only milking method and majority of the respondents didn’t wash their hands and the udder of the animal before milking, indicating low community awareness and knowledge of sanitary milk production procedures. Plastic equipment which is difficult to clean and can increase milk contamination and spoilage was used. About 43.3% of the pastoralists and 76.67% of the agro-pastoralists were cleaning milk vessels regularly. The most often used plant species for smoking milk handling equipment in the study area to extend shelf life and add flavor & aroma were Acacia ethaica, Blanites galabra, and Solanum Carense. The main constraints to hygienic goat milk in the area were identified to be poor barn hygiene, poor production procedures, disease, source of washing water and lack of extension services. In general, it can be concluded that handling and hygienic production practices of goat milk used in the study area were unsanitary, which may have been primarily caused by the community’s lack of awareness & understanding as well as a lack of supporting infrastructures. Therefore, the concerned bodies should place a high priority on the improvement of hygienic practices by carrying out various relevant development interventions, such as raising milk producers’ awareness, improving the health of goats, and providing the necessities for milk handling.

Microbiological Quality of Goat Milk in Degahbur District of Jarar Zone, Somali Regional State, Ethiopia

A cross-sectional study was carried out to evaluate microbiological quality of raw goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 40 pooled raw goat milk samples (each with a volume of 450 mL) were collected from the udders and milk handling equipment of targeted goat milk producers in the study area. The milk samples were subjected to laboratory analysis to evaluate total bacterial count (TBC) and total coliform count (TCC) in order to determine the microbiological quality of the raw goat milk in the study area. The study showed that the mean total bacterial count (TBC) and total coliform count (TCC) for raw milk samples collected from the udder were 4.92 ± 0.23 and 2.68 ± 0.36 log10 cfu·mL-1, respectively. The mean counts for samples collected from milk equipment were 5.61 ± 0.32 and 3.93 ± 0.21 log10 cfu·mL-1 for TBC and TCC, respectively. The values for the samples collected from pastoral production system were 5.63 ± 0.13 and 4.02 ± 0.20 log10 cfu·mL-1 for TBC and TCC, respectively. The average means of TBC and TCC for samples collected from the agro-pastoral production system were 4.9 ± 0.41 and 2.59 ± 0.37 log10 cfu·mL-1, respectively. Significant difference (P 0.05) in mean TBC and TCC was observed between milk samples collected from pastoral and agro-pastoral production systems as well as milk samples collected from udders and milk handling equipment of the producers. It could be concluded that both TBC & TCC of goat milk samples collected from the udder as well as from the milk handling equipment of producers exceeded the acceptable limits. This indicated that production practices performed during milk production and postharvest handling in the study area were unhygienic. Therefore, hygienic and proper milk production procedures should be followed to improve the quality of goat milk for its intended use in the study area.

Aqueous Two-Phase Systems Applied to Partition Proteins from Goat Milk Whey In-Nature

The proteins coming from the milk whey have numerous functional properties. Among the proteins with high bioactivity, α-lactoalbumin (α-La) and β-lactoglobulin (β-Lg) are present in large quantities in the milk whey. In the separation process of proteins, it is important to choose techniques which besides ensuring purity and high yield will not affect the molecule biological activity. The aqueous two-phase systems (ATS) have been utilized with success in the partition of these proteins, however, the studies were performed using protein in its pure form. Studies using milk whey in-nature and goat milk whey have not been found yet. In this context, the objective of this study was to evaluate the liquid liquid equilibrium of aqueous two-phase systems (ATS) in the partition of α-La and β-Lg from goat milk whey in-nature. Equilibrium data were performed considering ATS comprised of polyethylene glycol, potassium phosphate and water at 25°C and pH 7.0. The influence of the polymer molecular weight and amount of goat milk whey in-nature on the partition coefficient of these proteins were assessed. The partition coefficient, selectivity, process yield and purity of α-lactoalbumin and β-lactoglobulin proteins were determined. The results showed that the separation technique by aqueous biphasic systems is applicable indicating high efficiency in the whey proteins separation process.

Evaluation of 20 Macro and Trace Mineral Concentrations in Commercial Goat Milk Yogurt and Its Cow Milk Counterpart

Concentrations of 20 different minerals in commercial goat milk yogurt (CGY) and its cow milk yogurt (CCY) counterpart were evaluated in reference to goat milk yogurt manufactured from Fort Valley State University (FVGY), Fort Valley, GA, USA. Three different lots of CGY and CCY each were purchased from local retail stores at Warner Robins, GA, and 3 batches of FVGY were made using goat milk from the University milking herd. All 3 types of experimental yogurts were stored at 4°C refrigerator for 4 weeks. Twenty major and trace minerals were analyzed by an Inductively Coupled Plasma Optical Emissions Spectrometer (Thermo Jarrel Ash Enviro 36, Worchester, MA), using argon as the carrier gas and the EPA method 6010. Total solids (TS) content (%) of FVGY, CGY and CCY products were 11.03, 13.1 and 11.3, respectively, indicating CGY had higher TS than the CCY and FVGY yogurt. Respective mean mineral concentrations (ppm, wet basis) of FVGY, CGY and CCY were: Ca 1057, 1162, 1160;P 838, 974, 929;K 1327, 1717, 1208;Mg 102, 133, 113;Na 545, 449, 475;Fe 4.28, 3.33, 2.11;Mn 0.24, 0.19, 0.13;Cu 10.5, 9.85, 7.22;Zn 17.5, 11.7, 11.8. Levels of all macro minerals except potassium were higher in commercial goat and cow yogurts than FVGY, which may be due to the higher TS contents. FVGY had higher Fe, Mn, Cu and Zn than both commercial products. The heavy metal (Pb, Cd and Ni) contents (ppm) appeared to be normal range, while Al contents of FVGY, CGY and CCY were 11.9, 8.66 and 7.65, respectively, which were higher than those of Pb, Cd and Ni. Both commercial products contained higher major mineral contents than the university yogurt, which might be attributable to the differences in diet, breed, and stage of lactation of milking animals, as well as the tapioca additive used in the commercial products.

Evaluation of Total Fatty Acid Profiles of Two Types of Low-Fat Goat Milk Ice Creams

Effects of frozen-storage on fatty acids profiles and basic nutrient contents of two types of low-fat caprine milk ice creams were investigated during 0, 2, 4, 8 weeks of storage at -18°C. Two types of the experimental low-fat soft-serve goat ice creams were manufactured using whole (full-fat) milk and 2% fat goat milk with addition of commercial powdered vanilla flavor pre-mix containing 0.25% fat (Alpha Freeze, D466-A9047, Tampa, FL, USA). Fatty acid concentrations were quantified using a Thermo Electronic gas chromatography (GC)-MS (Model TRACE GC Ultra, Austin, TX, USA) equiped with an automatic sampler (Model AS-3000, Thermo Electronic Co.). The results showed that fat content was the only basic nutrient component exhibited the difference between the two types of ice creams, while no other components have shown differences between the two low-fat ice creams during the storage periods. The level of lauric acid (C12:0) was the highest among all 16 fatty acids, followed by palmitic (C16:0), linoleic (C18:1), and myristic acid (C14:0). The high levels of the medium chain fatty acids (C12:0 and C14:0) might have been derived from the goat milk as well as the palm oil asa part of the ingredients in the commercial ice cream premix. Among long chain fatty acids, palmitic acid (C16:0) was the highest, followed by oleic acid (C18:1) and stearic acid (C18:0). All of the long chain fatty acids contents were significantly higher (P < 0.05 or 0.01) in whole milk ice cream than those in 2% fat ice cream, except for the C22:0 and C24:00 acids. It was concluded that mean levels of the individual fatty acids in the caprine ice creams were significantly influenced by the types of milk fat used in the ice creams, but not by storage periods and storage × fat type interaction effects.

Composition of Triacylglycerols in Fats of Cow and Goat Milk Produced in Four Zones of Mexico

The study of the triacylglycerols (TAG) by gas chromatography (GC) using capillary columns is an efficient technique for the determination of some characteristics of quality of fats and oils. The objective of the present study was to determine by GC the content of TAG present in fat of cow and goat milk produced in four zones of Mexico. According to criteria established in Mexican Standardization, 25 samples were obtained of 1 L of ultra-pasteurized cow milk (UHT) and 27 and 48 of raw cow and goat milk, respectively. The fat was extracted from all of the milk samples by detergent solution, and was stored at –20℃ until its analysis. The chromatographic conditions made it possible to identify and quantify TAG of 28 to 54 numbers of carbons, which were analyzed under descriptive and inferential statistical techniques. For the cow milk fat, the statistical analyses indicated significant difference (p < 0.05) in the TAG C34, C50 and C52, and for the goat milk fat in the TAG of C36 to C52. No equality of means was found among the TAG of the cow and goat milk fat. This study offers an advance in the characterization of the TAG present in the cow and goat milk fat produced in Mexico.

Comparison of free fatty acid composition between low-fat and full-fat goat milk cheeses stored for 3 months under refrigeration

Differences in free fatty acid (FFA) compositions between low-fat (LF) and full-fat (FF: whole milk) goat cheeses were evaluated during 3 months at 4oC refrigeration. The two types of cheeses were manufactured using a bulk milk from the mixed herd of Saanen, Alpine, and Nubian goat breeds. LF cheeses were made using LF milk after cream separation. FFAs of all cheeses were extracted in diisoprophyl ether using polypropylene chromatography column, and FFA concentrations were quantified using a gas chromatograph equipped with a fused silica capillary column. Moisture, fat, protein contents (%) and pH of fresh LF and FF cheeses were: 55.1, 52.3;1.30, 25.6;35.7, 22.5;5.40, 5.42, respectively. The FFA contents (mg/g cheese) of fresh FF and LF cheeses prior to storage treatments for C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C16:0, C18:0, C18:1, and C18:2 were: 0.020, 0.072;0.070, 0.035;0.061, 0.055;0.181, 0.167;0.073, 0.047;0.174, 0.112;0.579, 0.152;0.308, 0.202;0.521, 0.174;and 0.057, 0.026, respectively. The respective FFA to total fatty acid ratios for 0, 1 and 3 months aged FF and LF cheeses were 8.44, 12.4;6.31, 16.91;12.03, 14.19. The LF cheeses generated more FFA than FF cheeses, while actual FFA content in FF cheese was significantly higher than in LF cheese. The FFA contents of LF cheese at 0, 1 and 3 months storage were 48.0, 96.8 and 36.4% of those of FF cheese, respectively. It was concluded LF cheese generated higher amount of FFA than FF cheese, although total FFA content was significantly (P<0.05) lower in LF cheese than in FF cheese.

Study Properties of Fermented Camels’ and Goats’ Milk Beverages Fortified with Date Palm (<i>Phoenix dactylifera L</i>.)

Camels’ milk (CM) and goats’ milk (GM) are rich in nutrients and vitamins necessary for the health of humans and have therapeutic properties as they are rich in antioxidants and have a protective role against free radicals that have harmful effects on human health. Date palm (DP), camels’ milk and goats’ milk have been reported to be used for the prevention and treatment of various diseases in Arab countries. This study was designed to mix date palm with camels’ milk and goats’. Eight formulations of both camels’ milk and goats’ were made from different percentages of date palm. These formulations were added at ratios of 0 (control), 10%, 20% and 30% (w/v) to camels’ milk and goats’ and the effect of this date palm on the composition and texture properties of the fermented obtained products were followed. It has been found that pH, protein, fat decreased and total solid, carbohydrate, ash, viscosity, vitamins, minerals and antioxidants increased with the increase of the added percentage of date palm compared to control. Microbial counts of the fermented camels’ milk (FCM) and goats’ milk (FGM) increased significantly (P < 0.05) with the addition of different formulations and during storage. Also, fermented camels’ milk (FCM) and fermented goats’ milk (FGM) fortified with different ratios date palm (DP) concentration resulted in good properties and higher acceptable sensory values (at a rate of 10% - 20%) in fresh and till the end of storage periods. The addition of the date palm to all treatments improved the composition, viscosity, microbiological quality of fermented camels’ and goats’ milk with nutritional functional values and acceptable sensory attributes.

The Effects of Graded Abomasal Glucose Infusion on Milk Yield and Composition in Lactating Goats

Four non-pregnant multiparous lactating goats were used in a 4 × 4 latin square experiment in the present study. The four treatments were abomasal infusion of 0, 50, 100, and 150 g d^-1 glucose. The results showed that graded glucose infusion increased milk yield （P 〈 0.01）. The highest milk yield was observed when 50 g d^-1 glucose was infused. An infusion of glucose at 100 or 150 g d^-1 failed to increase milk yield further and milk yield of the 100 g d ^-1 glucose infusion treatment was even significantly lower than that of the 50 g d^-1 treatment （P 〈 0.01）. Though milk fat content was gradually decreased by graded glucose infusions and milk fat yield of the 100 and 150 g d 1 treatments were lower than that of the control （P 〈 0.01）; milk fat yield of the 50 g d i treatment was not depressed and was higher than that of the control （P 〈 0.01）. Graded glucose infusion did not change the contents of milk protein and non-fatty solids. Yields of milk protein （P 〈 0.05）, lactose （P 〈 0.01）, non-fat solids （P 〈 0.01）, and lactose content （P 〈 0.01） of the 50 g d^-1 treatment were higher than those of the control but had no difference among the other three treatments. Contents of those de novo synthesized fatty acids in milk fat remained unchanged or increased and those preformed fatty acids remained unchanged or decreased by graded glucose infusion. Glucose infusion decreased the total yields of C16 ＋ C16：1 and 〉 C16 fatty acids and had no influence on the yield of C4-C14：1 fatty acids （P 〈 0.05）. Results of the present study implied that increased glucose supply had positive effects on the production of milk, milk protein, milk fat, and lactose only when glucose was a limiting factor for milk synthesis. Excessive glucose supply had no further beneficial effects and might depress milk fat synthesis.

Relationship between the Contents of MDA, the Activity of SOD in Serum of the Milk Goat with Fluorosis and the Erythrocytic Membrane Liquidity

To research the relation among the erythrocytic membrane.liquidity and the contents of MDA, the activity of SOD in serum of the milk goat with fluorosis. An animal model with fluorosis was constructed, and the fluorescent probe technique of DPH was used to measue the erythrocytic membrane liquidity. At the same time, the contents of MDA and the activity of SOD in serum were measured. The results showed that the erythrocytic membrane liquidity in the control group and flurosis group were 5.6742 ± 0.4417 and 3.7248 ± 0.4521 （P 〈0.01） respectively, the contents of MDA in serum were 2.0408 ± 0.198 and 4.494± 0.438 （P 〈0.01） respectively, the activities of SOD were 175.638 ± 22.201 and 113.714 ± 34.258 （P 〈0.01） respectively. The correlation analysis indicated that the relation between the activity of SOD and the liquidity of erythrocytic membrane was positive correlation （ r= 0.7321, P 〈0.05）, whereas the relation between the contents of MDA and the liquidity of erythrocytic membrane was negative correlation （r = -0.6438, P 〈0.01）. The erythrocytic membrane liquidity decreased in milk goat with fluorosis, which played a role in the occurrence and development of the fluorosis. There was correlation among the erythrocytic membrane liquidity and the contents of MDA, the activity of SOD.

Negative effects of long-term feeding of high-grain diets to lactating goats on milk fat production and composition by regulating gene expression and DNA methylation in the mammary gland

Background： It is well known that feeding a high concentrate（HC） diet to lactating ruminants likely induces subacute ruminal acidosis（SARA） and leads to a decrease in milk fat production. However, the effects of feeding a HC diet for long periods on milk fatty acids composition and the mechanism behind the decline of milk fat still remains poorly understood. The aim of this study was to investigate the impact of feeding a HC diet to lactating dairy goats on milk fat yield and fatty acids composition with an emphasis on the mechanisms underlying the milk fat depression. Seventeen mid-lactating dairy goats were randomly allocated to three groups. The control treatment was fed a low-concentrate diet（35% concentrate, n = 5, LC） and there were two high-concentrate treatments（65% concentrate, HC）, one fed a high concentrate diet for a long period（19 wks, n = 7, HL）; one fed a high concentrate diet for a short period of time（4 wk, n = 5, HS）. Milk fat production and fatty acids profiles were measured. In order to investigate the mechanisms underlying the changes in milk fat production and composition,the gene expression involved in lipid metabolism and DNA methylation in the mammary gland were also analyzed.Results： Milk production was increased by feeding the HC diet in the HS and HL groups compared with the LC diet（P 〈 0.01）, while the percentage of milk fat was lower in the HL（P 〈 0.05） but not in the HS group. The total amount of saturated fatty acids（SFA） in the milk was not changed by feeding the HC diet, whereas the levels of unsaturated fatty acids（UFA） and monounsaturated fatty acids（MUFA） were markedly decreased in the HL group compared with the LC group（P 〈 0.05）. Among these fatty acids, the concentrations of C15：0（P 〈 0.01）, C17：0（P 〈 0.01）, C17：1（P 〈 0.01）, C18：1 n-9 c（P 〈 0.05）, C18：3 n-3 r（P 〈 0.01） and C20：0（P 〈 0.01） were markedly lower in the HL group, and the concentrations of C20：0（P 〈 0.05） and C18：3 n-3 r（P 〈 0.01） were lower in the HS group compared with the LC group. However, the concentrations of C18：2 n-6 c（P 〈 0.05） and C20：4 n-6（P 〈 0.05） in the milk fat were higher in the HS group. Real-time PCR results showed that the m RNA expression of the genes involved in milk fat production in the mammary gland was generally decreased in the HL and HS groups compared with the LC group. Among these genes, ACSL1, ACSS1 ＆ 2, ACACA, FAS, SCD, FADS2, and SREBP1 were downregulated in the mammary gland of the HL group（P 〈 0.05）, and the expressions of ACSS2, ACACA, and FADS2 m RNA were markedly decreased in the HS goats compared with the LC group（P 〈 0.05）. In contrast to the gene expression, the level of DNA methylation in the promoter regions of the ACACA and SCD genes was increased in the HL group compared with the LC group（P 〈 0.05）. The levels of ACSL1 protein expression and FAS enzyme activity were also decreased in the mammary gland of the HL compared with the LC group（P 〈 0.05）.Conclusions： Long-term feeding of a HC diet to lactating goats induced milk fat depression and FAs profile shift with lower MUFAs but higher SFAs. A general down-regulation of the gene expression involved in the milk fat production and a higher DNA methylation in the mammary gland may contribute to the decrease in milk fat production in goats fed a HC diet for long time periods.

Exploring the Novel Genetic Variant of PITX1 Gene and Its Effect on Milk Performance in Dairy Goats

Paired-like homeodomain transcription factor 1 （PITX1） plays an important role in pituitary development by indirectly regulating the expression of the GH and PRL genes, and therefore PITX1 gene is regarded as a potential candidate gene for building the relationship between the gene polymorphism and milk traits. The aim of this study was to explore the novel genetic variant in PITX1 gene and its effect on milk performance in dairy goats. Herein, a novel genetic variation （NW_00314033： g.201GA or IVS1＋41GA） located at nt41 position of the first intron of the goat PITX1 gene was reported at the P1 locus, which can be genotyped by the Msp I PCR-RFLP. In the Msp I PCR-RFLP analyis, the GG variant was a major genotype, and the A variant was a minor allele in Guanzhong dairy goats which was at Hardy-Weinberg disequilibrium （chi-square χ2=140, P0.01）. The establishment of associations between different genotypes and milk performance was performed in the analyzed population. A total of three significant associations of the polymorphism with average milk fat content （%） （P=0.045）, morning milk fat content （%） （P=0.049）, and afternoon milk fat content （%） （P=0.050）, were found, respectively. A significant relationship between the polymorphism and average total solid content （P=0.029） was also detected. This novel single nucleotide polymorphism （SNP） extended the spectrum of genetic variation of the goat PITX1 gene, and its significant association with milk performance would benefit from the application of DNA markers related to improving milk performance through marker-assisted selection （MAS） in dairy goats.

Transfer of PUFA fatty acid protected and carnitin precursor on the ration of chemical composition of milk dairy goat

The experiment was conducted to investigate the effect of transfer of PUFA protected and carnitin precursor on the ration of chemical composition of milk dairy goat. In total, 10 female dairy goats of 2 - 4 years old Peranakan Etawah (PE) with body weight of 25 - 45 kg were used in this experiment. The feed material included a basal diet (control) based on yellow corn, rice bran, soya bean meal, coconut meal, tuna fish oil and lemuru fish oil. The method of the research was experimental in vivo using Randomized Completely Block Design (RCBD). There were 5 treatments in each experiment and 2 replications. The treatment consisted of P0 = control ration, P1 = P0 + 200 ppm L-carnitine on the ration, P2 = P1 + soya bean oil, P3 = P1 + protected tuna fish oil 5 ml or equal with 4% in the ration, and P4 = P1 + protected lemuru fish oil 5 ml or equal with 4% in the ration. The measured variable is chemical composition of milk dairy goat. The results of variance analysis showed that the effect of transfer of PUFA fatty acid in the rations contained 200 ppm L-carnitine significantly