Search Results (7)

This study examined the effects of incorporating processed (hydrolysed) (POP) and unprocessed (non-hydrolysed) (UOP) orange peels into the diets of lactating ewes on the proximate composition, fatty acid profile, antioxidant properties, physicochemical characteristics, and sensory attributes of traditional sheep milk yoghurt. Thirty-six Chios breed ewes were divided into three dietary groups: POP, UOP, and a conventional control diet (Control). Yoghurt produced from the UOP and POP diets had higher protein content (5.93 and 5.53%, respectively) and fat content (6.79 and 6.24%, respectively) compared to the Control (5.42% for protein and 6.06% for fat). Additionally, there were no significant differences in the nutritional indices of yoghurt fat. The determination of antioxidant activity showed no significant differences among the groups using the ABTS, DPPH, and FRAP methods, whereas significant differences were observed when measured with the Folin–Ciocalteu method. Textural analysis revealed that UOP yoghurt had greater firmness and cohesiveness. The whiteness index of yoghurt across all treatments remained consistent during storage, maintaining the desirable visual characteristics of traditional sheep milk yoghurt. Syneresis levels were similar across all groups, indicating no negative effects on yoghurt stability. Sensory evaluation confirmed the high acceptability of yoghurt produced from both experimental diets. These findings highlight the potential of orange peels as a sustainable feed additive, with no adverse effects on the nutritional, functional, or sensory properties of dairy products, while contributing to effective waste valorisation. Full article

Raw goat and ewe’s milk samples were used for the isolation of seven lactic acid bacteria new strains. After testing hemolytic activity and resistance to antibiotics, specific functional properties were evaluated; Lactococcus lactis subsp. lactis FBM_1321 and Lacticaseibacillus paracasei FBM_1327 strains resulted in the highest cholesterol assimilation percentages ranging from 28.78 to 30.56%. In addition, strong adhesion capacity to differentiated Caco-2 cells (1.77–21.04%) was mapped, and the lactobacilli strains exhibited strong antagonistic activity against foodborne pathogens compared to lactococci. The strains were able to grow at low pH and high NaCl concentrations, conditions that prevail in food systems (cell counts ranged from 1.77 to 8.48 log CFU/mL after exposure to pH 3 and from 5.66 to 9.52 log CFU/mL after exposure to NaCl concentrations up to 8%). As a next step, freeze-dried immobilized Lc. paracasei FBM_1327 cells on oat flakes were used for the preparation of functional yoghurt and ayran products. Cell loads of the functional strain remained high and stable in both products (7.69 log CFU/g in yoghurt and 8.56 log CFU/g in ayran after 30 days of storage at 4 °C) throughout their shelf life. No significant changes in the volatile profile were noticed, and the new products were accepted by the panel during the sensory evaluation. Full article

Goat milk is gradually becoming the preferred milk by consumers worldwide, including Slovakia. It is also demanded as a functional and/or nutraceutical drink as it is rich in bioactive components. However, another new development is the research into the beneficial autochthonous strains used to enrich goat dairy products. Among individual species, representatives in raw goat milk are also involved in lacticaseibacilli. Bacteriocin-like inhibitory substance-producing Lacticaseibacillus paracasei LPa 12/1 was isolated from raw goat milk. This study focuses on its potential as a new additive in dairy products. No mortality was found when checking the safety of the LPa 12/1 strain using Balb/c mice. The strain reached higher counts in ewe–goat milk yoghurt (up to 6.1 cfu/g log 10) than in cow milk yoghurt (almost 5.0 cfu/g log 10). Cow milk yoghurts remained in more stable consistency after LPa 12/1 supplementation compared with ewe–goat milk yoghurts, although specific organoleptic tests were not performed. However, LPa 12/1 has survived sufficiently in both types of yoghurts. This bacteriocin-like inhibitory substance-producing strain LPa 12/1 in its encapsulated form applied in yoghurts seems suitable to supplement dairy products. Full article

This work was carried out with the aim to investigate the microbiological, physicochemical, and sensory properties of an innovative yoghurt produced from ewe’s milk. Experimental yoghurt productions were performed with a commercial freeze-dried starter preparation and a natural milk starter culture (NMSC) of Streptococcus thermophilus and Lactobacillus delbrueckii. The two yoghurts did not differ for colour parameters, showing an average value of lightness, redness, and yellowness of 94.99, −3.74, and 9.37, respectively. The yoghurt produced using the NMSC as a fermenting agent was characterised by a significantly lower fat percentage and a higher antioxidant potential than commercial starters. Microbiological analysis confirmed the safety of the final product and a level of living lactic acid bacteria of 10⁸ CFU/g. Sensory analysis revealed some differences among yoghurts regarding unpleasant odour, homogeneity, and persistence in the mouth, but the yoghurt processed with NMSC was more appreciated. Thus, the production of ewe’s yoghurt fermented by a selected multi-strain starter culture represents an interesting strategy to enlarge the functional ovine dairy product portfolio. Full article

The objective of this work was the use of goat and sheep liquid whey concentrates (LWCs) produced by ultrafiltration (UF) for the manufacturing of frozen yoghurts. In a first step, natural yoghurts using only goat’s and sheep’s LWCs as raw material were obtained. One day after production, these yoghurts were used to produce frozen yoghurts with different concentrations of added inulin. The physicochemical characteristics of ewe’s and goat’s yoghurts were significantly different regarding dry matter, protein, fat and minerals. Ewe’s yoghurts were solid, while goat’s yoghurts behaved as a viscous liquid. Frozen yoghurts with different levels of inulin addition also presented significant differences concerning physicochemical and microbiological characteristics. Overrun was similar for all formulations except for that produced with ewe’s LWC containing 5.0% inulin, which presented a significantly higher value. Higher meltdown rates in goat’s frozen yoghurts were observed. The survival rates of lactic acid bacteria were lower than the data reported for similar products. Concerning sensory acceptance, both products showed encouraging results. It can be considered that the production of frozen yoghurts by using LWCs as the main ingredient can be an interesting option to broaden the product portfolio of small/medium scale dairy producers. Full article

The effect of a diet supplemented with a novel cornus extract, enriched with essential oils of oregano and thyme, on the performance of Chios cross-bred dairy sheep was investigated during the summer period. The plant extracts were prepared using a “green” method based on aqueous extraction. A total of 45 lactating ewes were allocated into three equal groups in a randomized block design. The three groups were fed the same feed allowance, roughage based on Lucerne hay and wheat straw and a concentrate based on cereals and oil cakes (the control diet). The diet of two groups was fortified with cornus extract, with or without oregano and thyme essential oils, at a level 0.515 g of plant extract/essential oils per kg of concentrate. Individual milk yield was recorded weekly and feed refusals were recorded on a pen basis daily, during a six-week period of lactation. Milk samples were analyzed for the chemical composition of protein, fat, lactose and solids-not-fat constituents, somatic cell counts and total viable bacteria counts. Moreover, the milk of each group was used for yoghurt and Feta cheese production. The lipid oxidative stability, protein carbonyl content and fatty acid composition of milk, yoghurt and cheese samples were also evaluated. The results showed that the incorporation of novel plant extracts and essential oils increased the milk production per ewe. Dietary supplementation with cornus extracts and essential oils lowered lipid and protein oxidation in milk, yoghurt and cheese samples, compared to the control. However, diet supplementation with herbal extracts did not affect the fatty acid profile in milk, cheese and yoghurt or the serum biochemical parameters. In conclusion, dietary supplementation with cornus in combination with oregano and thyme has the potential to improve feed utilization and the performance of high-yield dairy Chios cross-bred ewes reared under heat stress. Full article

Among developed countries, bovine milk production makes a major contribution towards the economy. Elevating consumer demand for functional foods has triggered a niche for non-bovine milk-based products. Mixing milks from different species can be a strategy to increase the consumption of non-bovine milk and enable consumers and dairy companies to benefit from their nutritional and technological advantages. Thus, this review aimed to gather the most important research on yoghurts derived from processing mixtures of milks of different species. We discuss the impact of milk mixtures (i.e., species and milk ratio) on nutritional, physicochemical, sensory, rheological and microbiological properties of yoghurts. More specifically, this paper only highlights studies that have provided a clear comparison between yoghurts processed from a mixture of two milk species and yoghurts processed from a single species of milk. Finally, certain limitations and future trends are discussed, and some recommendations are suggested for future research. Full article