The stability of the casein-gluconate matrix in reduced-lactose kefir with soluble fraction polysaccharides containing β-glucan from Pleurotus ostreatus

Storage Stability of Texture and Sensory Properties of Yogurt with the Addition of Polymerized Whey Proteins

Herein, we examined the possibility of producing probiotic yogurt with the addition of polymerized whey protein (PWP). It was determined that the yogurt was stable in terms of syneresis, texture, and sensory features. No spontaneous whey syneresis (SWS) was found in PWP yogurt during 21 days of refrigerated storage at 3 ± 0.5 °C. PWP yogurt had a 5.3% higher water retention capacity (WHC) than yogurt with whey protein concentrate (WPC). Compared with yogurt with unpolymerized protein, PWP yogurt had a higher absolute cohesiveness and viscosity index. The addition of whey protein concentrates to native and polymerized form resulted in longer maintenance of the original yogurt coherence than the control yogurt during storage. PWP yogurt had the same color saturation as the control yogurt. The polymerization of whey proteins resulted in a vanilla pudding aftertaste in yogurt and increased butter flavor 2.5-fold.

Pollution Abatement of Heavy Metals in Different Conditions by Water Kefir Grains as a Protective Tool against Toxicity

This research paper addresses the hypothesis that Water Kefir grains can be used as absorbers of metal ions and reports the first application of the Water Kefir grains as a protective tool against toxicity by heavy metal ions. The aim of this study is to evaluate the concentration of heavy metal ions in several Water Kefir solutions during the fermentation process under various conditions. Two colonies of Water Kefir grain were used, and the concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb, Ba, and Ca were measured in Water Kefir grain solutions at different contact times (0, 24, 48, and 72 hours), different pH values in citric and acetic buffers, and different Water Kefir grains/metal solution ratios, with and without sucrose (5%). Optical emission spectroscopy was used to measure the concentrations of metal ions. Among the tested experimental conditions, the best combination for pollution abatement is sucrose (5%), contact time 24 hours, starting pH = 4.5, acetate buffer, and Kefir grains/metal solution ratio 1 : 1. In these conditions, the heavy metal abatement by Water Kefir grains is particularly effective for Cr and Pb (70%) and good for Cu, Ni, and Mn (50%).