基于孔隙行为的低含油率马铃薯片/条调控机制

Potato chips or strips have an important position in convenience food field because of its special flavor and property. This project is mainly aimed at solving the problems existed in the potato chips or strips, such as the higher fat content, obscure fat absorption mechanism, and lack of guideline for fat absorption control. The modeling foods and actual potato slices or strips would be used as testing material in this project. The key characteristic of water replacement, condensation mechanism, capillary mechanism and surface-active mechanism existed from material to entire frying chain would be excavated. The relationships between the foods constitute and pore formation, pretreatment and pore formation, frying process and pore formation, pore characteristic and fat absorption, and the mechanism of low-fat potato chips or strips would be investigated. Effects of interaction of foods constitute, water evaporation, cellular damage, polarity change on the pore formation and fat absorption would be clarified. The universality control mechanism of low-fat potato chips or strips would be established from the point of foods constitute selecting, controlling of water evaporation and cellular damage during pretreatment and frying, intervening of fat- material polarity. The results would provide the theory basis and scientific guideline for the production of low-fat healthy foods.

油炸薯片/条因其特有的风味和品质在方便食品中占有重要地位，课题针对目前油炸薯片/条油脂含量较高、具有普适性的油脂吸收机制尚未明确、油脂调控存在较大盲目性等问题，以模拟体系和实际马铃薯片/条为试材，挖掘从原料到完整油炸链条中影响水分替代、冷凝机制、毛细管和表面活性机制的本质特征-孔隙，重点研究食品组成与孔隙形成、预处理与孔隙形成、油炸过程与孔隙形成、炸后孔隙特征与油脂吸收的关系，以及低含油马铃薯片/条的调控机制；阐明不同预处理和油炸过程中组分相互作用、水分蒸发、细胞损伤、极性变化对样品孔隙形成和油脂吸收的影响规律；从物料组成选择、预处理和油炸过程水分蒸发与细胞损伤控制、油-物界面的极性干预等角度，建立具有普适性的基于孔隙行为的低含油率马铃薯片/条的调控策略与调控机制，为健康低脂薯条/片的生产提供理论依据与科学指导。

课题针对目前油炸薯片/条油脂含量较高、具有普适性的油脂吸收机制尚未明确、油脂调控存在较大盲目性等问题，以模拟体系和实际马铃薯片/条为试材，重点研究了食品组成与孔隙形成、预处理与孔隙形成、油炸过程与孔隙形成、炸后孔隙特征与油脂吸收的关系，阐明不同预处理和油炸过程中组分相互作用、水分蒸发、细胞损伤、极性变化对样品孔隙形成和油脂吸收的影响规律，基于水分、孔隙、表面特性等角度解析了低含油马铃薯片/条的调控机制；结果表明，薯片的油脂吸收与其孔隙特性的变化密切相关，而超声预处理、热风干燥等预处理可调控马铃薯切片的孔隙特性，进而降低油炸过程中薯片的油脂吸收。直径范围为10 μm~100 μm和100 μm~200 μm的孔隙所占体积与油脂含量呈显著正相关（p < 0.01），直径范围为0.3 μm~10 μm的孔隙所占体积与油脂含量呈显著负相关（p < 0.05）。项目的研究建立了具有普适性的基于孔隙行为的低含油率马铃薯片/条的调控策略与调控机制，发表高水平学术论文11篇，申请国家发明专利4项，培养研究生4名，为健康低脂薯条/片的生产提供理论依据与科学指导。