脉冲电场处理对金桔质构影响及其机理研究

Effect of Pulsed Electric Field Treatment on Kumquat Texture and Its Mechanism

脉冲电场(PEF)作为一种高效非热加工技术可应用于干燥、提取、灭菌、浸渍等方面。文中从硬度、咀嚼性、弹性等角度研究PEF预处理对金桔质构特性的影响规律,解释金桔品质变化的原因。结果表明:PEF处理强度为1.0~2.0 kV/cm条件下,金桔纤维素结晶度减小,链间距离增大,结构更松散,导致金桔硬度和咀嚼性降低;半纤维素结构崩塌,分子链变短,亲水性提高,润胀性更佳,导致金桔弹性提高;果胶分子量减小,导致金桔硬度和粘着性降低,在金桔浸渍加工的参数选择和工艺优化等方面具有一定的指导价值。

As a high-efficiency non-thermal processing technology,pulsed electric fields(PEF)can be applied in drying,extraction,sterilization,and immersion procedures of food production.The influence of PEF pretreatment on the texture characteristics of kumquat from the perspective of physical properties(hardness,chewiness,elasticity,etc.)was studied in this article.Moreover,the reasons resulting in the quality change of kumquat were discussed.Experimental results show that the crystallinity of kumquat cellulose decreases and the distance between chains increases when the PEF treatment intensity is between 1.0 to 2.0 kV/cm,thus the structure become looser which leads to the decrease of hardness and chewiness.When the hemicellulose structure collapses,molecular chain become shorter,and hydrophilicity and swelling property are improved,resulting in better elasticity.The reduction of molecular weight of pectin leads to the decrease of kumquat's hardness and adhesion.This study can provide guidance for the improvement of immersion and maceration process in food industry.