Goat Milk Kefir Research Articles

The Physicochemical, Microbiology, and Sensory Characteristics of Kefir Goat Milk with Different Levels of Kefir Grain

Kefir is a fermented milk product. The kefir grain starter consists of lactic acid bacteria and yeast that produce lactic acid and alcohol. The quality of kefir is strongly influenced by the type of milk used, the amount of kefir grain, kefir grain microorganisms, and the incubation period. The characteristics of goat-milk kefir with the addition of different amounts of kefir grain were studied by measuring pH value, ethanol content, and percentage of lactic acid. The experimental design was a completely randomized design (RCD) with three treatments and five replications. The treatments were performed by using different amounts of kefir grains i.e., 2%, 4%, and 6%. Goat-milk kefir was pasteurized at 105oC for 5 minutes, cooled at room temperature (37oC), and then kefir grain was added at different levels and incubated for 12 hours. The results showed that the amounts of kefir grain had a significant effect (p<0.05) on pH value, the percentage of lactic acid, and ethanol content of goat-milk kefir produced. The higher dose of kefir grain had an influence on physicochemical characteristics, microbiology, and sensory of goat-milk kefir. The optimal characteristics of goat-milk kefir were 2% kefir grain with a pH value of 5.40, lactic acid content of 0.14%, and ethanol content of 0.69%. The weight gain of kefir grain was 7.21% and the total of lactic acid bacteria was 1.64x107 CFU/mL. Sensory quality had a white color, kefir scent, a non-acid taste, and like preference. It is concluded that the best goat-milk kefir can be produced by the addition of 2% kefir grain based on physicochemical, microbiological, and sensory characteristics.

Proteomic analysis of goat milk kefir: Profiling the fermentation-time dependent protein digestion and identification of potential peptides with biological activity

Kefir is a fermented dairy product, associated to health benefits because of being a probiotic and due to the presence of molecules with biological activity. In this work, we have profiled the peptide composition of goat milk kefir at three different fermentation times using a peptidomics approach, in order to study changes in peptide concentrations and patterns of protein digestion throughout the fermentation time. We identified 2328 unique peptides corresponding to 22 protein annotations, with a maximum of peptides found after 24 h fermentation. We established different digestion patterns according to the nature of the proteins, and quantified the changes in the peptides appearing in all the fermentation times. We also identified 11 peptides that matched exactly to sequences with biological activity in databases, almost all of them belonging to caseins. This is the most comprehensive proteomic analysis of goat milk kefir to date.

Assessment of the antibacterial activity of goat milk kefir on Escherichia coli ATCC 8739 and Salmonella enteric subsp. enterica serovar typhimurium ATCC 14028 using a well diffusion method

Kefir is a fermented dairy product that uses kefir grains, which contain lactic acid bacteria and yeast, as a starter. Kefir has various health-promoting properties as a prebiotic food product. The purpose of this research was to measure the antibacterial activity of goat milk kefir against the pathogenic bacteria Escherichia coli ATCC 8739 and Salmonella enteric subsp. enterica serovar typhimurium ATCC 14028 using a well diffusion method. A total of five treatments were tested: kefir grain, kefir curd, kefir whey, distilled water as a negative control, and tetracycline antibiotic as a positive control. The research used a Completely Randomized Design (CRD), and the data were analyzed by ANOVA if it showed significant effects by Least Significant Difference Test (LSD). The highest antibacterial activity against E. coli ATCC 8739 was seen with kefircurd,2.98±0.65 mm, and the lowest with kefir grains, 2.82±0.83 mm. Similarly, antibacterial activity against S. typhimurium ATCC 14028 was lowest with kefir grains, 2.22±1.05 mm, and the highest with kefir curd, 2.34±1.65 mm. The results showed that kefir goat milk, both curds, whey and kefir grains have potential as antibacterial against pathogenic E. coli ATCC 8739 and S. enteric subsp. enterica serovar typhimurium ATCC 14028.

Microbiological properties of preparing facial mask cream from goat milk kefir

Many studies have been published on physicochemical, microbiological and bioactive compound on kefir but the study of microbiological and pysicochemical properties to address the preparation of producing facial mask cream from goat milk kefir have never been investigated. The current study provided the optimum incubation time of goat kefir to produce facial mask cream. Total plate count, total lactic acid bacteria, total yeast, titratable acidity and ethanol content were evaluated from goat milk kefir with different incubation time: 18, 24, 30 and 36 h under conditions of controlled incubator temperature (30 ± 1°C). The lactic acid flora and microbial count between incubation time 18 to 30 h increased by about 1.09 and 1.14 log units, respectively. The sample made using incubation time 24 h had higher total yeast and alcohol content while the sample made using incubation time 36 h had higher titratable acidity.

Effect of enzymatic conversion of lactose on the flavour profile of goat milk kefir and its permeate after microfiltration

The aim of the study was to analyse the flavour profile and general lust of innovative dairy products – kefir, which has increased health-oriented values resulting from an increase in the ratio of whey protein and an enzymatic bioconversion of lactose. Kefir was prepared from a mixture of goat milk and its permeate concentrated with microfiltration and ultrafiltration processes, combined in a ratio of 6:4. The permeate addition increases sweetness and reduces overall flavour of the dairy. The enzymatic conversion of lactose into galactooligosaccharides further increases the sweetness of the dairy mixture, while simultaneously weakening the odours both goatish and processed.

Goat Milk Kefir Supplemented with Porang Glucomannan Improves Lipid Profile and Haematological Parameter in Rat Fed High Fat and High Fructose Diet

Abstract Background and Aims: Diet with a high fat and high sugar is associated with an increased incindence of the metabolic syndrome. Kefir has been known as a natural probiotic, while glucomannan from porang (Amorphophallus oncophyllus) tuber was demonstrated as prebiotic in vivo. Probiotics and prebiotics can be used adjuvant nutritional therapy for metabolic syndrome. The aim of this study was to evaluate the effect of goat milk kefir supplemented with porang glucomannan on the lipid profile and haematological parameters in rats fed with a high-fat/high-fructose (HFHF) diet. Materials and methods: Rats were divided into 5 groups: normal diet; HFHF; HFHF + kefir; HFHF + kefir + glucomannan; and HFHF + simvastatin. Results: There were significant differences before and after treatment in triglycerides and total cholesterol in HFHF + kefir+glucomannan group. The HFHF rats administered kefir with or without glucomannan had higher levels of lymphocytes and lower neutrophils compared to HFHF group (p&lt;0.05). Only goat milk kefir without glucomannan proved to reduce platelets number. Conclusion: Goat milk kefir supplemented with porang glucomannan could improve the health of rats fed high-fat/high-fructose, by decreasing plasma triglycerides, total cholesterol, and their immunomodulatory effect by decreasing number of neutrophils and increasing the lymphocytes. Especially for goat milk kefir had antithrombotic activity which important to prevent cardiovascular diseases.

Microbiological Characteristic and Nutrition Quality of Goat Milk Kefir Based on Vitamin D3 Fortification Time

Goat milk kefir fortified with vitamin D3 is expected to benefit individual with insulin resistance. Different vitamin D3 fortification time allegedly effect microbiological characteristic and nutrition quality of goat milk kefir due to its microbial growth curve, thus this study aimed to analyze those parameters. This study was an experimental research. This study contains five treatments (vitamin D3 fortification at 0, 6, 12, 18, or 24 hours of fermentation) and a group of control. Total lactic acid bacteria, vitamin D3, protein level, fat contain, crude fiber, viscosity, and pH was analyzed by Total Plate Count, spectrophotometry, Bradford method, Babcock method, gravimetric analysis, Ostwald method, and pH meter respectively. Time of vitamin D3 fortification significantly effect vitamin D3 content (p=0,021), fat content (p=0,001), crude fiber (p=0,0001), viscosity (p=0,010), and total lactic acid bacteria (p=0,048). The highest vitamin D3 content was found on the group fortified at 6 hours of fermentation. All treatment groups has lower fat content and crude fiber content than control group. Total LAB in all group meet the Codex standard (≥ 107 CFU/ml). Control group and fortification group at 24 hours of fermentation have higher viscosity than other groups. There was no significant difference found in goat milk kefir protein level (p=0,262) and pH (p=0,056) despite the difference of fortification time. Vitamin D3 fortification time effect vitamin D3 content, fat content, crude fiber, viscosity, and total lactic acid bacteria of goat milk kefir, but did not effect protein content and pH of goat milk kefir.

Nutrition Quality and Microbiology of Goat Milk Kefir Fortified with Vitamin B12 and Vitamin D3 during Storage

Goat milk kefir fortified vitamin B12 and vitamin D3 can be an alternative to improve insulin resistance. Fortification of vitamin B12 and vitamin D3 could affect the balance of complex ecosystems of bacteria and yeasts in goat milk kefir. We analyzed the nutritional quality and microbiology of goat milk kefir during storage. This experiment was done with completely randomized design consisted of five treatments, ie storage day 0, 3rd, 6th, 9th, and 15th. Vitamin B12, vitamin D3, protein were analyzed using spectrophotometric, fat using babcock method, total lactic acid bacteria using total plate count, pH with pH meter, and viscosity using ostwald method. During 15 days in refrigerated storage, there was no significant difference (p>0,05) of vitamin B12 concentration, protein, fat, and viscosity of kefir. Storage time of the final product caused the decrease of vitamin D3 concentration between day 9 and 15 (p=0,038), pH (p=0,023), and total lactic acid of kefir (p=0,0001). Total lactic acid bacteria increased until 9 days of storage (6161 ± 1.296x107cfu / ml), but decreased to 24% on day 15 (150 ±7.78x107cfu/ml). pH kefir tends to fluctuate during storage with the highest pH value of 4,38 on day-3, and lowest 4.13 on day-9.

Physichochemical Properties of Kefir Drink Using Modified Porang Flour (Amorphophallus oncophyllus) During Storage Period

The purpose of this research was to compare physicochemical characteristics of goat milk kefir drink produced by using porang flour and modified porang flourthroughout 21 days storage period. Goat milk kefir drink weretaken at 1, 7, 15 and 21 day of storageperiod, analysed for microstructure, particle size and ethanol content. Analyses of microstructure using confocal laser scaning microscopy (CLSM), particle size using particle size analyser,ethanol content usinggas chromatography (GC).There were significant differencesconsidering the microstructure, particle size and ethanol content of goat milk kefir drink using modified porang flour during storage period.Lower ethanol content was observed in goat milk kefir drink with porang flour and modified porang flour as compared to control sample (no porang flour added) addition, lower ethanol in sample resulted from lower metabolism activity of microbial under lower water activity condition effect of glucomannan in porang flour. Goat milk kefir drink with modified porang flour addition produced lower particle diameter than control and porang flour treatment, it may due to the disruption of milk protein aggregate by modified porang flour. Confocal microscopy showed at modified porang flour treatment shows more homogenous protein milk aggregate.It can be concluded that modified porang flour produced lower ethanol content and particle diameter of goat milk kefir drink and more homogenous protein milk aggregate.

KUALITAS KIMIA, FISIK DAN SENSORI KEFIR SUSU KAMBING YANG DISIMPAN PADA SUHU DAN LAMA PENYIMPANAN BERBEDA

The objective of this research was to investigate the chemical, physical and sensory properties of goat milk kefir during storage under different temperatures and storage time. Experimental method, applied completely randomized factorial design. The first factor was temperature (-1 to -5oC; 5 to 10oC and 6 to 10oC) and the second factor was storage time (10; 20 and 30 days) followed by Duncan test. Result showed that temperature, storage time and interaction highly significantly affected (P&lt;0.01) the level of ethanol and FFA, but not affected (P&gt;0.05) on protein content, fat and ash but CO2 level, texture and flavor of kefir were affected by storage time. Kefir viscosity was only affected by storage temperature (P&lt;0.05). Research concluded that storage temperature affected chemical properties such as ethanol, FFA and kefir viscosity,while kefir sensory properties was predominantly affected by storage

THE DEVELOPMENT OF GOAT MILK KEFIR AND TOFU AT MENDHO SUBIREJO FARM KECAMATAN PURWODADI KABUPATEN PASURUAN

The purpose of IbM program were the strengthen of technology adoption in milk coagulation, packaging and refrigeration at “Mendho Subi Rejo” farm to produce goat milk kefir and tofu thereby the production capacity were improved. “Mendho Subi Rejo” farm has produced and sold goat milk kefir and tofu with specific taste and texture. The application of coagulation technology, continue packaging and refrigeration at “Mendho Subi Rejo” farm improved the coagulation of goat milk tofu, the packaging of goat milk kefir and tofu, and stabilization goat milk produck during storage in refrigeration showcase. The application of these technology improved the production capacity of goat milk kefir and tofu

Development of a technology with an iodine-containing additive to produce kefir from goat milk

The authors have suggested a technology of making goat milk kefir using an iodine-containing supplement – Elamine. The applicability of the iodine-containing additive Elamine was determined in experimental batches of goat milk kefir in terms of increasing the amounts of macro and micro nutrients, including organic iodine and essential amino acids and fatty acids. Tests were conducted to specify the physicochemical and biochemical properties of the aforementioned additive. It has been determined that Elamine contains calcium, phosphorus, copper, manganese, iron, and iodine in the amounts of 1.293, 0.156, 0.612, 0.915, 3.42 and 554 mg/kg, respectively. This indicates that the iodine-containing additive comprises in its composition a balanced set of macro and micro elements in an organically bound form. The contents of iodine, phosphorus, calcium, and iron are higher than in other additives. According to the FAO/WHO scale, the scores of all the essential amino acids of the iodine-containing supplement Elamine (threonine, valine, methionine+cystine, isoleucine, leucine, phenylalanine+tyrosine, and tryptophan) are 15.5, 19.6, 17.1, 32.5, 17 3, 176.4 and 37.0 % higher than in the ideal protein. The only exception is the amino acid lysine, whose score was found to be by 28.5 % lower, compared to the same property of the ideal protein. This indicates that the protein of the iodine-containing supplement is of full value as to the content of essential amino acids. Adding Elamine to a milk mixture in a concentration of 0.10...0.15 mass % increased the amounts of essential amino acids and fatty acids in the experimental batches of kefir. This additive stimulates the growth of lactic acid bacteria in kefir up to 2.2×107…2.5×107 CFU/cm3 (2.2-2.5 times in comparison with the control sample). The amount of yeast in the experimental batches of kefir increased slightly – by 0.5 CFU/cm3, compared with the reference. The increased amounts of beneficial microflora components in the experimental batches of kefir stimulated the intensity of the lactic fermentation of milk sugar. This contributed to reducing the milk clot formation time by 2 hours (6 hours instead of 8 hours in the control sample). The aforementioned allows recommending dairy processors of Ukraine to implement the advanced technology of producing cost-effective high-quality kefir from goat milk

Goat milk kefir with black rice extract reduced insulin resistance through suppressing RBP4 expression in diabetic rats

Goat milk kefir with black rice extract reduced insulin resistance through suppressing RBP4 expression in diabetic rats

Antidiabetic Potential of Kefir Combination from Goat Milk and Soy Milk in Rats Induced with Streptozotocin-Nicotinamide.

The study aimed to evaluate the effect of kefir combination from goat milk and soy milk on lipid profile, plasma glucose, glutathione peroxidase (GPx) activity and the improvement of pancreatic β-cell in diabetic rats. Male rats were divided into five treatments: normal control, diabetic control, goat milk kefir, combination of goat milk-soy milk kefir and soy milk kefir. All rats were induced by streptooztocin-nicotinamide (STZ-NA), except for normal control. After 35 d experiment, the rats were sampled for blood, sacrificed and sampled for pancreatic tissues. Results showed that diabetic rats fed kefir combination had higher (p<0.05) triglyceride than the rats fed goat milk or soy milk kefir. Decreasing of plasma glucose in diabetic rats fed kefir combination was higher (p<0.05) than rats fed goat millk kefir. The activity of GPx in diabetic rats fed three kinds of kefir were higher (p<0.01) than untreated diabetic rats. The average number of Langerhans and β-cells in diabetic rats fed kefir combination was the same as the normal control, but it was higher than diabetic control. It was concluded that kefir combination can be used as antidiabetic through maintaining in serum triglyceride, decreasing in plasma glucose, increasing in GPx activity and improving in pancreatic β-cells.

Nitric Oxide and Inflammatory Cytokine Productions in Diabetic Rats Supplemented with Goat Milk and Soy Milk Kefir

Diabetes has been known as an inflammatory diseases, and the certain of probiotics when administered in adequate amounts were reported have an anti-inflammatory properties. The purpose of this study were to evaluate the effect of administration of goat milk and soy milk kefir on immune responses including spleen lymphocyte proliferation, production of pro-inflammatory cytokine (TNF-α) and anti-inflammatory cytokine (IL-10), as well as peritoneal macrophage nitric oxide (NO) production in diabetic rats induced with streptozotocin-nicotinamide. Male Wistar rats were divided into five groups: negative control, positive control, diabetic rats fed goat milk kefir, diabetic rats fed kefir combination from goat milk and soy milk kefir and diabetic rats fed soy milk kefir. After 5 weeks treatment, the rats were sacrificed and sampled for spleen and peritoneal macrophages. The results showed that kefir combination from goat milk and soy milk kefir could increase lymphocyte proliferation and IL-10 production, as well as decreased TNF-α significantly (p<0.05) in diabetic rats. However, the effect of kefir combination showed the lowest NO production in diabetic rats compared with goat milk kefir and soy milk kefir. In conclusion, kefir combination from goat milk and soy milk may be used as biotherapeutic for type-2 diabetes mellitus by improving systemic immune responses through increasing in lympocyte proliferation and IL-10 as well as decreasing in TNF-α production.

The Influence of Goat Milk and Soybean Milk Kefir On IL-6 and Crp Levels in Diabetic Rats

Abstract Background and Aims: Hyperglycemia increases inflammation in type 2 diabetes mellitus (T2DM). Goat and soybean milks have been known to reduce inflammation. The aim of this study is to evaluate the effect of goat milk and soybean milk kefir on IL-6 and CRP levels in diabetic rats. Materials and Method: A total of 25 male Wistar rats were divided into the following groups: 1) normal rats; 2) diabetic rats; 3) diabetic rats with intake of goat milk kefir; 4) diabetic rats with intake of soybean milk kefir; and 5) diabetic rats with combination of both types of kefir. Before kefir administration for 4 weeks, plasma glucose was measured. After treatment, plasma glucose, CRP and IL-6 levels were assessed. Results: There was a significant decline of plasma glucose in diabetic rats with goat milk kefir (p=0.021), and in diabetic rats with the combination of both goat milk and soybean milk kefir (p&lt;0.001). After treatment, CRP level in diabetic rats was significantly higher when compared with those that had goat milk kefir (p=0.043). All of diabetic rats with kefir had IL-6 values significantly lower than diabetic rats without it (p=0.021). Conclusion: Both goat milk and soybean milk kefir can reduce IL-6 level, but only goat milk kefir can reduce CRP in diabetic rats.

CHEMICAL AND MICROBIOLOGICAL CHARACTERISTICS OF GOAT MILK KEFIR DURING STORAGE UNDER DIFFERENT TEMPERATURES

This research was conducted to study the chemical and microbiogical properties of goat milk kefir stored under different temperatures and storage time. A completely randomized design, factorial pattern 3 x 3 was used in this study. The first factor was storage temperature (-1 to -5; 1 to 5 and 6 to 10 o C) and the second factor was storage time (10; 20 and 30 day s ). Each treatment has three replicates. Variables observed included pH, water activity (aw), total lactic acid bacteria (LAB), and total yeast. Data were subject to analysis of variance and Duncan’s multiple range t est . Results showed that storage time and temperature had significant effects on pH. The lowest pH of Kefir was obtained by storing it for 10 days at 6 to 10 o C. Titratable acidity was significantly affected by temperature, and kefir stored at 6 to 10 o C has the highest titratable acidity. Storage time and temperature had no significant effects on water activity, and the average water activity of kefir was 0.875±0.028. Total LAB and total yeast were significantly affected by temperature, but not by storage time. In average, total LAB and total yeast in kefir were 7.17± 0.92 log cfu/ml and 6.76± 0.39 log cfu/ml , respectively . In conclusion, this study confirmed that temperature of storage has a major contribution to the characteristics of kefir made from goat milk; hence it has to be considered when handling kefir for a longer period of time.

COMPARISON OF THE ANTIBACTERIAL ACTIVITY OF COW MILK KEFIR AND GOAT MILK KEFIR AGAINST BACTERIA Bacillus cereus

Background: Kefir is fermented milk and comes from the Caucasus. Kefir is made by inoculating cow milk, goat or sheep with kefir grain. Kefir contains 0.5–1.0% alcohol and 0.9 to 1.1% lactic acid. This product is very popular in the Soviet Union, where the consumption of kefir reach 4.5 kg per capita per year. Kefir made from pasteurized milk and fermented with kefir grain, kefir grain is white seeds from bacteria colony, such as Streptococcus sp., Lactobacilli and some types of yeast/yeast apatogen. As a probiotic drink, kefir contains bacteria of lactic acid and acetic acid bacteria in kefir are giving acidity and produces secondary metabolites that bacteriocins that kill pathogenic bacteria such as Bacillus cereus . Method: This study used cow milk and goat milk kefir as a starting material, to produce a cow milk kefir and goat milk kefir. Cow milk kefir and goat milk kefir were compared antibacterial activity against Bacillus cereus . Previously each made 3 variations of the concentration of 2%, 4%, and 6% kefir grains were added cow milk and goat milk. Antibacterial activity tested using Kirby Bauer method so that the observation a clear zone formed on the media was the inhibition activity of the bacterium Bacillus cereus . The results were analyzed by ANOVA, Mann Whitney, and Tukey with a significance of 95%. Result: The results showed that goat milk kefir has better antibacterial activity against Bacillus cereus compared to cow milk kefir. Goat milk kefir with kefir seeds concentration of 6% has the best antibacterial activity with inhibition zone diameter of 6 mm. Keywords: kefir, Bacillus cereus , cow milk, goat milk

Microbiological Quality, Fatty Acid and Amino Acid Profiles of Kefir Produced from Combination of Goat and Soy Milk

3 Abstract: The microbiological quality, fatty acid and amino acid profiles were studied in kefir prepared from combination of goat and soy milk (100:0), (50:50) and (0:100). Total counts, total of lactic acid bacteria (LAB) and total yeast of kefir were counted with Standard Plate Count (SPC). Fatty acids composition was analyzed by gas chromatography (GC), whereas amino acids composition was analyzed by high performance liquid chromatography (HPLC). The results showed that there were no significant difference in total counts, LAB and yeast of all kefir. The acidity of kefir made from soy milk only was lower (p<0.05) than kefir made from goat milk or combination of goat and soy milk, whereas there were no significant difference in pH. Caproic (C6:0), heptadecanoic (C17:0), behenic (C22:0) and pentadecanoic (C15:1) acid of kefir made from 50% goat milk and 50% soy milk mixture (50:50) were lower (p<0.05) than goat milk kefir (100:0), but the oleic acid (C18:1) of kefir made from combination of 50:50 was higher (p<0.05) than 100:0. The amino acids composition of kefir made from goat milk only (100:0) and combination 50:50 was not significantly different. Therefore, this study suggests that soy milk can substitute 50% of goat milk to produce kefir without changing the microbiological quality, acidity, pH value, amino acids profile and even increase the oleic acid.

Study of the Microbial and Chemical Properties of Goat Milk Kefir Produced by Inoculation with Taiwanese Kefir Grains

One of the prerequisites for the successful implementation of industrial-scale goat kefir production is to understand the effects of different kefir grains and culture conditions on the microbial and chemical properties of the goat kefir. Thus, the objectives of the present study were to evaluate the characteristics of kefir grains in Taiwan on the microbial and chemical properties of goat milk kefir, as well as to understand the influence of culture conditions on production of medium chain-length triglycerides (MCT). Kefir grains were collected from households in northern Taiwan. Heat-treated goat milk was inoculated with 3-5% (V/W) kefir grains incubated at 15, 17.5, 20 or 22.5°C for 20 h, and the microflora count, ethanol content, and caproic (C6), caprylic (C8), and capric acid (C10) levels measured at 4 h intervals. Our results indicate that incubation with kefir grains results in 10 6 -10 7 CFU/ml microflora count and 1.18 g/L of ethanol content at 20 h of fermentation. Incubation with 5% kefir grain at 20-22.5°C produces the highest MCT levels. (Asian-Aust. J. Anim. Sci. 2005. Vol 18, No. 5 : 711-715)