Microbiological, chemical, fatty acid and antioxidant characteristics of goat milk kefir enriched with Moringa oleifera leaf powder during storage

Development of nutri-functional paneer whey-based kefir drink

Present research focused on biotransformation of paneer whey into a functional fermented product using kefir culture. Out of 9 formulations (S-1 to S-9) tried; S-8, obtained by fermenting FOS (1%) supplemented paneer whey and adding 8% refined sugar, was identified as the most acceptable product. Nutritional analysis revealed the following as per 100 g of product: 44.24 kcal total energy, 8.29 g carbohydrates, 7.19 g sugar, 1.51 g protein, 0.52 g total fat, 0.13 g saturated fat, 0.30 g MUFA, 0.23 g ash, 49.7 mg sodium content, 0.51% (w/w) alcohol and 4.5% (v/v) CO2. Results revealed a notable decline in pH and a rise in acidity during the early stages of storage followed by stabilization thereafter. Additionally a progressive decrement in lactose content and increase in ethanol was reported owing to the fermentation activity of the diverse microflora in kefir culture. The product exhibited antimicrobial as well as antioxidant activity and also remained stable for 12 days under refrigeration. Microbial stability was further strengthened by the absence of E.coli and consistent viable count of lactic acid bacteria and yeast in confirmation with the microbiological standards of fermented milk products. Results indicated that both proteinaceous as well as non-proteinaceous components are responsible for antioxidant activity of the product. Hence, the development of paneer whey-based kefir could relieve hassle of waste management and also provide health benefits.

Evaluation of Spreadable Kefir Produced from Different Milks in Terms of Some Quality Criteria

Kefir, which has many beneficial effects on health, is one of the most consumed fermented milk products worldwide. It is important to increase consumption of the fermented product for public health. In this study, it was aimed to increase the beneficial effects of kefir on public health. Therefore, kefirs produced from different types of milk (cow, buffalo, sheep, and goat) were concentrated, and obtained spreadable kefir samples were investigated in terms of their microbiological characteristic (lactic bacilli, lactic cocci, yeasts and moulds, total bacteria, and coliform bacteria), benzoic acid content, physicochemical properties (fat, total solid, ash content, acidity, pH, syneresis, viscosity, colour, and rheological properties), and sensory characteristic. It was determined that APC, lactic bacilli, lactic cocci, and yeast counts of the concentrated kefir samples changed between 6.90 and 8.64, 6.89 and 8.61, 7.42 and 8.72, and 2.17 and 5.39 log CFU/g, respectively, during storage. Mould and coliform bacteria were not detected in the samples. The concentrated kefir samples contained benzoic acid in the range of 18.30-119.58 mg/L. Results from this study showed that type of milk caused differences on APC, lactic bacilli, lactic cocci and yeast count, total solids, ash, fat, acidity, pH, syneresis, colour, viscosity and rheological parameters, and benzoic acid content. In addition, milk type affected sensory properties of the kefirs. Concentrated kefirs produced from cow and buffalo milk were the most liked by panellists. Finally, it was determined that concentrated kefir was favoured as a new product by most of the panellists.