Impact of type and level of stabilizers and fermentation period on the nutritional, microbiological, and sensory properties of short-set Yoghurt

Effect of nanoemulsified and encapsulated Planiliza abu protein on fortified yogurt

Fortified dairy products such as yogurt have attracted a lot of attention due to the increasing concern for public health. This study aimed to determine the effects of nanoemulsified and a microencapsulated protein hydrolysate obtained from Planiliza abu on some of the properties of yogurt. The physicochemical, rheological, microbiological, and sensory evaluation of the fortified yogurt samples stored at 4°C were assessed during 21 days. The fish protein hydrolysates (FPHs) < or >10 kDa protein were used. The amino acid profile of Planiliza abu was glutamic acid (78.99%), aspartic acid (59.53%), and lysine (53.54%). No significant change was observed in titratable acidity (TA) and pH of supplemented yogurts during refrigeration. The highest survival level of lactic acid bacteria (LAB), water-holding capacity (WHC), and viscosity and the lowest syneresis were observed in fortified samples with FPH <10 kDa. The highest ferric reducing antioxidant power (FRAP) was achieved in yogurt fortified with nanoemulsion FPH < 10 kDa (NEh10a, 0.41 mg/g). The results showed that fortified yogurt with FPH, particularly less than 10 kDa, is among the desirable functional food with appropriate gel network and consistency as well as better taste and mouth feel, and higher overall acceptance.

Antibacterial activity of bioemulsifiers/biosurfactants produced by Levilactobacillus brevisS4 and Lactiplantibacillus plantarumS5 and their utilization to enhance the stability of cold emulsions of milk chocolate drinks

Chocolate milk drink, one of the most popular and widely consumed milk products among the population, independent of their age, has as its main challenge the problem of its physical instability. The aim of this study was to assess the stabilizing effect of bioemulsifiers/biosurfactants (BE/BS) from two lactobacilli strains in a cold chocolate milk drink. The strains Levilactobacillus brevis S4 and Lactiplantibacillus plantarum S5 isolated from pendidam were screened for their ability to produce BE/BS. The produced BE/BS were characterized, their antimicrobial activities were assessed, and their ability to stabilize cold chocolate milk drinks was determined. The results obtained showed BE/BS yields of 3.48 and 4.37 g/L from L. brevis S4 and L. plantarum S5, respectively. These BE/BS showed emulsifying and surface activities that remained stable after treatment at different temperatures, pH, and salinity. The emulsions formed using BE/BS were stable for 72 h at room temperature (25 ± 1°C). The BE/BS exhibited antimicrobial activity against Staphylococcus aureus S1 and Escherichia coli E1. When applied to cold chocolate milk drinks at 0.2% (w/v), the BE/BS from L. brevis S4 and L. plantarum S5 showed interesting solubility indexes and water absorption capacities, which led to the successful stabilization of the drinks. The results of this study demonstrate the stabilizer potential of BE/BS from L. brevis S4 and L. plantarum S5 and suggest their use in the dairy and food industries.

Application of natural and modified additives in yogurt formulation: types, production, and rheological and nutraceutical benefits

Yogurt, a popular fermented dairy product, is of different types and known for its nutritional and nutraceutical benefits. However, incorporating additives into yogurt has been adopted to improve its functionality and nutraceutical properties. Additives incorporated in yogurt may be natural or modified. The incorporation of diverse natural additives in yogurt formulation, such as moringa, date palm, grape seeds and argel leaf extracts, cornelian cherry paste, mulberry fruit and leaf powder, lentil flour, different types of fibers, lemongrass and spearmint essential oils, and honey, has been reported. Similarly, modified additives, such as β-glucan, pectin, inulin, sodium alginate, and gelatin, are also added to enhance the physicochemical, textural, sensory, and rheological properties of yogurt. Although additives are traditionally added for their technological impact on the yogurt, studies have shown that they influence the nutritional and nutraceutical properties of yogurt, when added. Hence, yogurts enriched with functional additives, especially natural additives, have been reported to possess an improved nutritional quality and impart several health benefits to consumers. These benefits include reducing the risk of cardiovascular disease, cancer, osteoporosis, oxidative stress, and hyperglycemia. This current review highlights the common types of yogurt, the production process, and the rheological and nutraceutical benefits of incorporating natural and modified additives into yogurt.