直流电场下水包油型乳液中鱼油油滴聚并、析出行为的研究

为了寻找多脂鱼类深加工利用方法,达到鱼油提取和鱼蛋白高值利用的双重目的,本文系统研究了直流电场下水包油型乳液中鱼油的析出行为,具体包括:乳液中油滴聚并的微观结构、宏观现象观测;内部因素(磷脂含量和离子强度等)和外部条件(电压和温度)对乳液稳定性和电场作用下鱼油析出行为的影响;直流电场对鱼油中活性活性成分的影响。结果表明,直流电场未缩短鱼油析出的动力学过程时间,但增强了油滴的聚集和聚并。一定量的磷脂(2 mg/m L)会明显增加鱼油析出量(从37.5%提高到63.9%)。离子强度高于0.02 M以上时具有促进油滴聚并的效果,其中氯离子和钠离子分别是阴阳离子影响作用较大的种类。鱼油析出量在电压从0 V升高时明显增加,超过800 V以上时趋于稳定。温度的影响与常规破乳方法中相似。电场作用对其中多种不饱和脂肪酸均未有破坏作用。

Coalescence and Separation of Fish Oil Droplets in Oil-in-water Emulsions under Direct-current Fields

A new electric demulsification method was proposed to more effectively process fatty fish, achieving both fish oil extraction and high-value utilization of fish protein. The coalescence and separation of fish oil droplets in oil-in-water emulsions under a direct-current field was systematically investigated. The microstructure and macroscopic phenomena during fish oil droplet coalescence, the influence of internal factors (phospholipid content and ionic strength) and external conditions (voltage and temperature) on emulsion stability, the coalescence and separation of fish oil droplets under electric field, and the impact of direct-current electric field on active ingredients in fish oil were studied. The results showed that the presence of the electrical field did not shorten the time required for fish oil separation, but enhanced the probability of oil-droplet coalescence. A certain level of phospholipid content (2 mg/mL) was found to raise the demulsification rate from 37.5% to 63.9%. Ionic strength higher than 0.02 M had a positive effect on the coalescence of fish oil droplets. Chlorine and sodium ions were better than sulfate and potassium ions, respectively, for coalescence. The volume of separated fish oil increased when the voltage magnitude was increased from 0-800 V, and remained relatively constant above 800 V. Influence of temperature was similar to that in traditional demulsification process. Additionally, treatment by direct-current electric field had virtually no impact on the active ingredients of fish oil.