蛋黄蛋白抗冻肽的制备及其对猪肉糜冻藏品质的调控

Preparation of Egg Yolk Protein Antifreeze Peptides and Their Regulation of Frozen Quality in Minced Pork

摘要:

为同时解决蛋黄油副产物浪费和猪肉糜冻藏过程中抗冻保护的难题,开发一种蛋黄蛋白抗冻肽(egg yolk protein antifreeze peptides, EYP-AFP),探究该抗冻肽在食品保鲜中的应用潜力。从脱脂蛋黄粉中提取多肽,以酵母菌存活率及水解度为指标,优化酶解条件,并评估EYP-AFP对猪肉糜冻融过程中理化性质的影响。结果表明,在先使用碱性蛋白酶(56℃、90min,pH值为9,酶活力为9890U)后使用中性蛋白酶(45℃、125min,pH值为8,酶活力为10100U)的条件下制备的EYP-AFP,可使冻融酵母菌存活率提高至94.44%±1.05%。将质量分数为2%、4%、6%的EYP-AFP分别加入猪肉糜内,3次冻融循环后,6％EYP-AFP组的样品解冻、蒸煮损失率分别较无添加组降低了18.3%和20.24%,保水性提高了16.53%,pH值升高了0.18。颜色、质构和电子鼻的测定结果表明,EYP-AFP可以改变肉糜颜色,降低熟肉糜的硬度、弹性、咀嚼性及内聚性,使甲基类、醇类物质和氢化物等挥发性物质增多。此外,在1次冻融循环后,6％EYP-AFP组样品较无添加组不易流动水含量提升了11.66%,自由水含量降低了11.38%；同时,微观结构分析表明,EYP-AFP可以填充在肌肉纤维束周围,使其表面结构更加致密。研究结果表明,EYP-AFP可以有效抑制猪肉糜冻融过程的组织损失、水分迁移和冰晶生长,提升肉糜持水能力,让肉糜的质地变得更为松软。研究旨在为蛋黄油副产物再利用和猪肉糜贮藏稳定性提升提供新的思路。

Abstract:

The challenges of waste from egg yolk oil byproducts and freeze protection during pork mince freezing were simultaneously addressed, egg yolk protein antifreeze peptides (EYP-AFP) were developed to explore their potential applications in food preservation. Peptides were extracted from defatted egg yolk powder. Enzymatic hydrolysis conditions were optimized based on yeast survival rate and degree of hydrolysis. The effects of EYP-AFP on physicochemical properties during pork mince freezing and thawing were evaluated. Results indicated that preparing EYP-AFP under conditions of alkaline protease treatment (56℃, pH 9,90min, 9890U) followed by neutral protease treatment (45℃, pH 8,125min, 10100U) increased yeast survival rate after freeze-thaw cycles to 94.44%±1.05%. When EYP-AFP was added to pork mince at mass fraction of 2%, 4% and 6%, after three freeze-thaw cycles, the 6% EYP-AFP group exhibited 18.3% and 20.24% reductions in thawing and cooking losses, respectively, compared with the untreated group. Water retention capacity increased by 16.53%, and pH rose by 0.8. Color, texture and electronic noise measurements indicated that EYP-AFP altered the color of minced pork, reduced the hardness, elasticity, chewiness, and cohesiveness of cooked minced meat, and increased volatile compounds such as methyl compounds, alcohols, and hydrogenated compounds. Furthermore, after one freeze-thaw cycle, the 6% EYP-AFP group exhibited an 11.66% increase in non-flowing water content and an 11.38% decrease in free water content compared with the untreated group. Simultaneously, the determination of microstructure indicated that EYP-AFP filled the spaces around muscle fiber bundles, resulting in a denser surface structure. The results indicated that EYP-AFP effectively inhibited thawing loss, water migration, and ice crystal growth during the freeze-thaw process of pork mince, enhanced its water-holding capacity, and improved texture softness. This study aimed to provide new insights for reusing egg yolk oil byproducts and addressing the poor storage stability of pork mince.