Xie Huan, Sha Xiao-Mei, Shan Shan, Hu Zi-Zi, Tu Zong-Cai
National R&D Center for Freshwater Fish Processing, College of Chemistry and Chemical Engineering and College of Life Science, Jiangxi Normal University, Nanchang, China.
State Key Laboratory of Food Science and Resources, Nanchang University, Nanchang, China.
J Sci Food Agric. 2025 Feb;105(3):1691-1700. doi: 10.1002/jsfa.13947. Epub 2024 Oct 7.
Emulsions are thermally unstable systems. This research aimed to investigate the thermal stability of fish gelatin (FG) oil-in-water emulsions in the presence of poly-γ-glutamic acid (γ-PGA) as an additive after heat treatment. The study assessed how γ-PGA influences the thermal stability of FG emulsions over time, focusing on their properties, structure, and food application potential.
The incorporation of γ-PGA significantly enhanced the thermal stability of FG emulsions, preserving their morphology after heating. Emulsions containing 0.1% γ-PGA showed no significant changes after 24 h at 90 °C, while emulsions without γ-PGA experienced noticeable delamination. Rheological evaluations revealed that the energy storage modulus and loss modulus of FG-γ-PGA emulsions remained consistently higher than those of FG emulsions, regardless of heating duration. Particle size analysis indicated minimal changes for FG-γ-PGA emulsions (413 nm after 24 h) compared to a substantial increase for FG emulsions (1598 nm). After heating, FG-γ-PGA emulsions demonstrated significantly higher emulsifying activity index (EAI) (74 m g versus 22.7 m g) and emulsifying stability index (ESI) (97% versus 76%). Additionally, the texture properties of meat mince formulated with FG-γ-PGA emulsions were comparable to those containing fat, showcasing their potential as a fat replacement.
The study concludes that γ-PGA enhances the thermal stability of FG emulsions, maintaining their integrity and improving functional properties under heat treatment. These findings offer valuable insights for the formulation of thermally stable emulsions, presenting promising opportunities for innovative applications in the food industry. © 2024 Society of Chemical Industry.
乳液是热不稳定体系。本研究旨在探讨在热处理后，作为添加剂的聚γ-谷氨酸（γ-PGA）存在下鱼明胶（FG）水包油乳液的热稳定性。该研究评估了γ-PGA如何随时间影响FG乳液的热稳定性，重点关注其性质、结构和食品应用潜力。
γ-PGA的加入显著提高了FG乳液的热稳定性，加热后保持了其形态。含有0.1%γ-PGA的乳液在90℃下放置24小时后无显著变化，而不含γ-PGA的乳液出现明显分层。流变学评估表明，无论加热时间长短，FG-γ-PGA乳液的储能模量和损耗模量始终高于FG乳液。粒度分析表明，FG-γ-PGA乳液变化极小（24小时后为413nm），而FG乳液大幅增加（1598nm）。加热后，FG-γ-PGA乳液表现出显著更高的乳化活性指数（EAI）（74m g对22.7m g）和乳化稳定性指数（ESI）（97%对76%）。此外，用FG-γ-PGA乳液配制的碎肉的质地特性与含脂肪的碎肉相当，显示出其作为脂肪替代品的潜力。
该研究得出结论，γ-PGA提高了FG乳液的热稳定性，在热处理下保持其完整性并改善功能特性。这些发现为热稳定乳液的配方提供了有价值的见解，为食品工业中的创新应用带来了广阔前景。©2024化学工业协会。
