Physico‐Chemical Properties, Probiotic Survivability, Microstructure, and Acceptability of a Yogurt‐Like Symbiotic Oats‐Based Product Using Pre‐Polymerized Whey Protein as a Gelation Agent

Abstract

Consumption of a food product containing prebiotics and probiotics has been recognized as an important factor in lowering risk of intestinal cancer and gastrointestinal diseases and risks associated with high cholesterol. An oats-based symbiotic yogurt-like food (Oagurt) was developed using oats and probiotics (Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium), with pre-polymerized whey protein (PWP) as a gelation agent. The product was also fortified with inulin to increase soluble fiber, minerals, and vitamins. Physico-chemical analyses and 9 wk shelf life for viability of probiotics and changes in pH and viscosity were carried out for formulations with (F) and without (C) fortification. Results of the shelf life study showed that both L. casei and Bifidobacterium remained at therapeutic levels: 4.8 x 10(6) CFU/g (F), 4.3 x 10(6) CFU/g (C) and 3.1 x 10(6) CFU/g (F), 3.17 x 10(6) CFU/g (C) after 9 wk. However L. acidophilus did not survive after 3 wk. Viscosity and pH decreased significantly during the study with the difference between formulations also significant for pH (P < 0.0001). Scanning electron microscopy of samples revealed that the pre-polymerized whey protein played a major role in the structure of the gel with an increased protein network structure visible at higher PWP levels. A consumer acceptability study showed that the product was "fair" for all organoleptic attributes.

Physicochemical, rheological and stability characterization of a caramel flavored yogurt

“…The HF yogurt shows fragments of large globular aggregates of casein with porous zones (Fig. 3D and E); appearance previously observed by Penna, Subba, and Barbosa-Cánovas (2007), Ramirez-Santiago et al (2010), and Walsh, Ross, Hendricks, and Guo (2010), an effect which is pronounced by the fat content increasing.…”

Consistency, microstructure and probiotic survivability of goats’ milk yoghurt using polymerized whey protein as a co-thickening agent

“…Microstructure of the yoghurt samples made with 0.4% PWP, 0.3% pectin and mixture of 0.4% PWP and 0.3% pectin was examined using scanning electron microscopy (SEM) according to the procedures of Walsh, Ross, Hendricks, and Guo (2010). Samples were prepared by embedding the yoghurt samples into agar cubes and were fixed in 2.5% glutaraldehyde in 0.1 M sodium cacodylate buffer (pH 7.2) and post fixed in 1.0% osmium tetroxide followed by …”

Sodium tripolyphosphate inhibits the formation of lysinoalanine in heat-treated whey protein

“…For example, heat-induced polymerized whey protein has been applied in the non-fat goat milk yogurt as a thickening agent and fat replacer (Zhang, Mccarthy, Wang, Liu, & Guo, 2015). Prepolymerized whey protein was used as a gelation agent in the symbiotic oats-based yogurt-like product (Walsh, Ross, Hendricks, & Guo, 2010). However, the heat treatment of whey protein under alkaline condition can result in the formation of lysinoalanine (LAL) via amino acid cross-linking-an undesirable phenomenon in food processing (Al-Saadi, Easa, & Deeth, 2013;Calabrese, Mamone, Caira, Ferranti, & Addeo, 2009;Cattaneo, Stuknyte, Masotti, & De Noni, 2017).…”