氧化咖啡酸交联乳清蛋白膜的热学、光学特性及水汽渗透率、消化率研究

食品科学 ›› 2012, Vol. 33 ›› Issue (19): 133-137.

氧化咖啡酸交联乳清蛋白膜的热学、光学特性及水汽渗透率、消化率研究

王耀松，熊幼翎*，陈洁

江南大学食品学院，食品科学与技术国家重点实验室

收稿日期:2012-07-09 修回日期:2012-09-06 出版日期:2012-10-15 发布日期:2012-09-17
通讯作者: 熊幼翎 E-mail:ylxiong@uky.edu
基金资助:
江南大学食品科学与技术国家重点实验室目标导向课题

Oxidized Caffeic Acid Cross-linked Whey Protein Films: Thermal Properties, Light Transmittance, Water Barrier Properties and in vitro Digestibility

Received:2012-07-09 Revised:2012-09-06 Online:2012-10-15 Published:2012-09-17
Contact: Youling Xiong E-mail:ylxiong@uky.edu

摘要/Abstract

摘要： 采用氧化咖啡酸作为交联剂，研究其对乳清蛋白交联所成膜的热、光、水汽渗透和消化等功能特性。咖啡酸溶液经氧化后以质量分数2%和4%的量(以蛋白量为基础)加入到6g/100mL、90℃热变性的乳清蛋白溶液(pH8.0)，采用铺展法制备蛋白膜。利用SDS-PAGE、差示扫描量热法、热重技术等方法来表征氧化咖啡酸对乳清蛋白的交联性和膜功能性的影响。结果表明：氧化咖啡酸主要通过促进二硫键和部分非还原共价键交联蛋白，使蛋白成膜的热稳定性提高。此外，这种交联处理能显著降低膜材料的光通透率和透明性，但对水汽渗透率无显著性降低作用。体外消化实验结果显示较高质量分数的氧化咖啡酸处理可显著降低膜的消化性。

关键词: 可食性膜, 乳清蛋白, 氧化咖啡酸, 交联, 热性质, 光透性, 水汽透性, 消化性

Abstract: Oxidized caffeic acid (OCA) was employed to induce cross-linking in whey protein-based films. The thermal properties, light transmittance, water barrier properties, and in vitro digestibility of the resultant whey protein films were analyzed. OCA at 2% and 4% (based on protein content) application levels was incorporated into 6 g/100 mL heat-denatured (90 ℃) whey protein isolate (WPI) solutions before casting to form films. The protein cross-linking behavior and film functionality were characterized by electrophoresis, differential scanning calorimetry (DSC), and thermogravimetry. The results showed that OCA promoted whey protein cross-linking primarily via disulfide bonds and partial non-reducible covalent bonds, leading to an improved thermal stability of the resultant films. OCA treatment significantly lowered the light transmittance and transparency, but slightly reduced the water vapor permeability (WVP) of the films. The in vitro digestion experiments carried out using pepsin and pancreatin showed that hydrolysis of the films was inhibited when higher concentrations of OCA were incorporated.

Key words: edible films, whey protein isolate, oxidized caffeic acid, cross-linking, thermal properties, light transmittance, water vapor permeability, digestibility

王耀松，熊幼翎*，陈?洁. 氧化咖啡酸交联乳清蛋白膜的热学、光学特性及水汽渗透率、消化率研究[J]. 食品科学, 2012, 33(19): 133-137.

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