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In this study, varying concentrations of polyunsaturated fatty acids in goat’s milk were obtained by supplementing goat feed rations with maize dried distillers grains with solubles (DDGS). In comparison to the control group, the milk of goats that received DDGS contained about 25% more polyunsaturated fatty acids, 30% more conjugated linoleic acid (CLA), and had more favorable values of the atherogenic and thrombogenic indices. The diverse composition of fatty acids present in the goat’s milk correlated with the olfactory perception of the milk and its volatile compound profile. The level of unsaturated fatty acids significantly affected the odors detected in the processed goat’s milk. The volatile compound profile of the milk was mostly differentiated by the concentrations of aldehydes (hexanal and furfural) and furanones (furaneol), which exceeded their odor threshold values. The total concentration of identified aldehydes was highest in pasteurized milk samples from the goats of the experimental group, as a result of heating. Furfural was found in pasteurized samples of both the control and experimental milk at concentrations exceeding its odor threshold (3 mg·kg−1). Feeding goats with DDGS did not change the animal, cooked, dairy fat, lack of freshness, light-oxidized, or overall dairy flavors of the raw milk. After pasteurization, milk from goats fed with DDGS retained its characteristic animal odor and gained a very intense cooked flavor.

Mare milk is a valued and sought-after raw material for the production of innovative dairy products. The high demand, low supply, high price, and lack of accurate characterization of the milk of a given horse breed may provoke its deliberate fraudulent dilution. The aim of this work was to analyze the freezing point against a background of various selected technological parameters of Polish Coldblood mare milk. Research was carried out on multiparous Polish Coldblood mares from 5 to 8 yr of age with live weights between 618 and 851 kg. Their milk was tested on d 1, 3, and 7 postpartum and once a month for the next 9 mo of lactation (n = 52). Milk from 13 mares, taken daily in mo 4 of lactation, was collected for the dilution study (n = 403). The basic composition of the milk was as follows: solids-not-fat, 84.4 g/kg, fat 15.1 g/kg, lactose 65.3 g/kg, and total protein 24.2 g/kg (made up of casein, 14.6 g/kg, and whey protein, 9.5 g/kg). The dominant amino acids were glutamic acid, proline, leucine, and aspartic acid. The mean freezing point during a 9-mo lactation was -0.557°C (coefficient of variation = -2.787; 5th to 95th percentile: -0.563 to -0.550°C). Based on our analysis, we adopted -0.550°C (from 3 to 6 mo) as the reference value for milk from the Polish Coldblood horse. Analysis of the model of changes in freezing point, after dilution, using the coefficient of determination and Akaike's information criterion, showed that a linear model could be recommended (y = 79.35 + 144.35x). Addition of 1% water increased the freezing point of Polish Coldblood mare milk by 0.0069°C.

The aim of this work was to demonstrate the influence of mare milk fermentation type on the amino acid profile, especially the content of tryptophan, water-soluble vitamins and magnesium. Additionally, the atherogenic, thrombogenic and hypercholesterolaemic fatty acid index was analysed. The dominant amino acids of mare milk were glutamic acid, leucine, lysine, and aspartic acid. Fermentation of mares' milk did not affect the riboflavin, cobalamin, and magnesium content. The type of lactic acid bacteria used had no effect on the free tryptophan content of fermented milk. The free tryptophan content of fermented mares' milk was 0.062 mg 100 g−1 (Δ22% compared with unfermented milk). The sum of saturated fatty acid concentration was lower in fermented than in the unfermented mares' milk. Atherogenic index was lower in mare milk than in fermented mares’ milk. The values of fatty acids with a hypocholesterolaemic effect and hypercholesterolaemic fatty acids decreased in fermented milk.

Color is important for the consumer when making a purchase decision. Mare&rsquo, s milk and, thus, fermented mare&rsquo, s milk is little known to consumers. Thus, it is worth presenting research showing the extent of color change during the production and storage of mare&rsquo, s milk. Herein, we examined the range of color changes in mare&rsquo, s milk and cow&rsquo, s milks adapted to mare&rsquo, s milk composition. These samples were further fermented and stored for 3 weeks at 5 &plusmn, 1 &deg, C. Starter cultures containing Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus were used for fermentation. Mare&rsquo, s milk reached the required pH of 4.5 during fermentation faster (255 min) than cow&rsquo, s milk (300 min). After fermentation, mare&rsquo, s milk compared to cow&rsquo, s milk and adapted cow&rsquo, s milk had lower titratable acidity (0.75%) and firmness (145. 6 |(g∙s)|). The water holding capacity (95.6%) and number of Lactobacillus (7.71 log CFU/mL) and Streptocococcus (7.20 log CFU/mL) in mare&rsquo, s and other&rsquo, s milks were the same. Mare&rsquo, s milk was furthest from the ideal white (WI) color, with its chrome (C*) being 1.5-times larger than cow&rsquo, s milk. However, fermented mare&rsquo, s milk was darker than the fermented adapted milk and cow&rsquo, s milk by 36% and 58%, respectively. Storage caused a decrease in the WI, C*, and yellowness index (YI). The fermented mare&rsquo, s milk color stability during production and storage was less than that of fermented cow&rsquo, s milk. After 3 weeks storage, it was observed that the titratable acidity increased to 1.05%, and the pH decreased to 4.3 in fermented mare&rsquo, s milk. The water holding capacity decreased but was still higher compared to fermented cow&rsquo, s milk.