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Application of UPLC-MS/MS Method for Analysis of Apigenin, Apigenin 7-Glucoside and Chlorogenic Acid in Goat Serum
AbstractUPLC-MS/MS method was developed for determination of bioactive compounds including chlorogenic acid (CA), apigenin (AP) and apigenin 7-glucoside (AP7G) in goat serum. The analytes were separated on Kinetex C18 analytical column and a mobile phase consisting 0.1% formic acid in water and methanol with gradient elution. Detection of analytes was performed using a triple quadrupole mass spectrometer with electrospray ionization in positive mode. The lower limit of quantitation was 0.5 ng mL–1 for AP and AP7G and 2.5 ng mL–1 for CA. The inter- and intra-day precision of the method expressed as relative standard deviation was in the range of 1.22–14.5%. The accuracy of the method expressed as the relative error was in the range of 0.147–14.6%. The extraction recoveries of the compounds were 76.2–89.5%. The validated method was successfully applied for analysis of the compounds in the serum of sixty goats, half of which were fed with fodder with the addition of an herbal mixture. The higher concentration values of all analyzed compounds were reported in the serum of the animals fed with herbs compared to the control group receiving standard fodder.
Processability of milk in the production of curd cheeses on family farms in the summer and winter seasons
The aim of the study was to compare quality of curd cheeses produced from raw and pasteurized milk in a family farm in the summer and winter seasons. Conducted analyses showed that the season of the year, in which milk was produced, influenced its chemical composition and selected quality attributes. In terms of milk processability a more advantageous composition and better quality attributes were found in winter compared to summer. Quality of produced curd cheeses was affected by the season of milk production as well as milk type (raw vs. pasteurized). In the winter season the yield of curd cheese was over 1.5-fold greater from pasteurized milk in comparison to the summer season. Curd cheeses produced from raw milk were firmer, more elastic and sliceable, while those produced from pasteurized milk were less cohesive and more suitable was spreads. The organoleptic analysis of curd cheeses showed that more advantageous consumer value was found for cheeses produced in the winter season.
Effect of herbal feed additives on goat milk volatile flavor compounds
The aim of this study is to investigate the effects of herbal supplements administered to goats on sensory quality and volatile flavor compounds in their milk. The experiment was conducted on sixty Polish white improved goats randomly allocated into five feeding groups (four experimental and one control) of twelve goats each. The trial lasted 12 weeks. The experimental animals received supplements containing a mixture of seven or nine different species of herbs at 20 or 40 g/animal/day. The control group received feed without any herbal supplements. Milk obtained from experimental and control groups of animals was characterized by a low content of aroma compounds, with only 11 chemical compounds being identified. Decanoic methyl ester, methylo 2-heptanone and methylo-butanoic methyl ester had the highest share in the total variability of the tested aroma compounds (PCA). During the sensory evaluation, the smell and taste of most of the samples were similar (p > 0.05). However, the addition of herbal feed supplements lowered the concentration of Caproic acid (C6:0), Caprylic acid (C8:0) and Capric acid (C10:0), which caused a significant reduction in the goaty smell of milk. The obtained results indicate that the studied herbal supplements can reduce the intensity of goaty smell and allow goat milk production without modification of other sensory features.
Lactose Content and Selected Quality Parameters of Sheep Milk Fermented Beverages during Storage
The aim of the research was to evaluate lactose content and rheological, physical, chemical, and organoleptic parameters during the storage of fermented beverages made from sheep’s milk. The research was carried out on natural, probiotic, and Greek-type yogurts, as well as kefir. The products were made using the thermostat method from the milk of 42 East Frisian sheep in the middle lactation period, in duplicate. Lactose contents, active and titratable acidity, color by the L*a*b*C*h* system, and rheological parameters (hardness, consistency, consistency, and viscosity) were tested, and organoleptic assessments were carried out on the first, seventh, fourteenth, and twenty-first days of storing the drinks at 4 °C. Of all drinks, the highest reduction in lactose after 21 days of storage was found to occur in kefir (52% reduction) and, among the yogurts, in the Greek yogurt (41% reduction). The product with the lowest lactose content, regardless of the storage period, was kefir. This indicates that kefir is more suitable than yogurt for people with partial lactose intolerance. Effects of both inoculation type and beverage storage time were shown to exist for all parameters. It was also found that kefirs suffered deterioration in most rheological parameters and, in general organoleptic evaluation in the final period of storage. Based on our analysis, the optimal storage time for natural yogurts and sheep’s milk kefirs at 4 °C was 21 and 14 days, respectively.
The Effect of Herbal Feed Additives in the Diet of Dairy Goats on Intestinal Lactic Acid Bacteria (LAB) Count
Sixty dairy goats of the Polish white improved breed were randomly assigned to five feeding groups of twelve animals each. The animals received a supplement containing seven herbs at 20 or 40 g/animal/day (experimental groups 1 and 2) and a supplement containing nine herbs at 20 or 40 g/animal/day (experimental groups 3 and 4)m, along with pelleted concentrate feed. Group 5 (the control group) received pelleted feed without any herbal supplements. A significant effect of herbal feed additive on lactic acid bacteria (LAB) count was observed (p < 0.001). The highest number density of LAB was found in the goats receiving the feed additive with nine herbs at 20 g/animal per day (p < 0.05). There was a statistically significant effect of lactation stage on intestinal LAB count (p < 0.001). Regardless of the feeding group, the highest number density of LAB was found in animals at the peak of lactation. The LAB count was also affected by the interaction of diet group × lactation stage (p < 0.0001). A probiotic strain of Lactobacillus fermentum was identified in the faecal samples of goats receiving the herbal additive, but not in the controls. Genetic identification of the microorganisms isolated from the faeces of the experimental goats did not reveal the presence of harmful mould spores, although spores of the fungus Aspergillus fumigatus were detected in the controls.
Effect of herbal feed additives on milk performance and health status of dairy goats
Abstract Introduction Interest is increasing in natural feed additives that improve animal health, raise farming productivity and enhance the quality of animal products. These additives, especially polyphenols, are biologically active chemical compounds found in plants. Material and Methods Sixty dairy goats were randomly assigned to five feeding groups of 12 animals each. Over 16 weeks, the animals received a polyherbal supplement containing seven or nine herb species at 20 or 40 g/animal/day, along with pelleted concentrate feed. The health status of the animals was assessed based on the concentration of acute phase haptoglobin proteins and serum amyloid A in blood serum. Results A statistically significant positive effect of the herbal mixtures was found on the percentage of milk fat and fat : protein ratio (P-value < 0.05). The time of test-day milking and milk sampling had a significant impact on the level of all examined milk parameters (P-value < 0.001). Moreover, milk yield and fat-corrected milk yield were significantly affected by a feeding group × time of test-day milking and milk sampling interaction, influencing the level of examined parameters. Conclusion The use of herbal supplements in the diet of dairy goats did not negatively affect the goats’ milk production – neither the yield nor composition. A positive effect of the administered multi-herbal mixtures was found on % fat concentration and fat : protein ratio in milk.