Effect of poly-γ-glutamic acid on the stability of set yoghurts

• Published in: Journal of food science and technology Vol. 55; no. 11; pp. 4634 - 4641
• Main Authors: Yu, HaiYan, Liu, Han, Wang, Li, Zhang, Yan, Tian, HuaiXiang, Ma, Xia
• Format: Journal Article
• Language: English
• Published: New Delhi Springer India 01.11.2018; Springer Nature B.V
• Subjects: Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Crosslinking; Food Science; Glutamic acid; Nutrition; Original; Original Article; Particle size; pH effects; poly-γ-Glutamic acid; Porosity; Refrigeration; Rheological properties; Rheology; Stability; Studies; Yogurt; Set yogurt; Refrigerated storage; Rheology; Texture; Poly-γ-glutamic acid
• ISSN: 0022-1155; 0975-8402
• DOI: 10.1007/s13197-018-3404-7

The effects of poly-γ-glutamic acid (γ-PGA) on the stability of yogurt were studied in terms of texture, rheology, particle size, and microstructure. The effects of γ-PGA on the pH and water holding capacity (WHC) of yogurt during refrigeration were also studied. The tan δ value of the yogurt with 0.04% (w/w) γ-PGA was significantly lower than that of control. The addition of γ-PGA decreased the particle size. The yogurt with 0.02% (w/w) γ-PGA had denser network structure with less porosity, and cross-linking between complexes occurred with greater frequency. The pH of the yogurt supplemented with 0.02% and 0.04% γ-PGA was significantly higher. WHC increased with the amount of γ-PGA. The addition of γ-PGA to yogurt strengthened the antishear ability, inhibited the postacidification phenomenon, and improved stability during refrigeration.