醋酸酯淀粉对速冻调制食品中双乙酸钠测定的影响

Effect of acetate starch on the determination of sodium diacetate in quick-frozen food

淀粉变性方式众多,其中醋酸酯变性过程中加入了乙酸酐,反应过程中乙酸酐与醋酸酯淀粉在碱性条件下发生水解生成乙酸,从而影响了速冻调制食品中双乙酸钠的测定。为了明确速冻调制食品中双乙酸钠测定的干扰项,本文采用GB 5009.277-2016《食品安全国家标准食品中双乙酸钠的测定》对醋酸酯A-1和乙酰化二淀粉磷酸酯A-2两种木薯变性淀粉中双乙酸钠及添加不同比例淀粉的速冻调制食品中双乙酸钠含量进行测定,且检测了不同乙酰基取代度的变性淀粉乙酰基、双乙酸钠及乙酸本底含量。实验结果表明:淀粉经过乙酰化变性后,对食品中双乙酸钠的测定产生了显著的阳性干扰,其中速冻调制食品中双乙酸钠测定量与变性淀粉添加量呈线性正相关,同时变性淀粉中双乙酸钠含量与其乙酰化取代度显著正相关。综上所述,现行食品安全国家标准GB 5009.277-2016不适合添加了醋酸酯变性淀粉的速冻调制食品中双乙酸钠的测定。

Starch denaturation can be happened in many ways.One of them is due to adding acetic anhydride during acetate starch modifying process.Acetic anhydride and acetate starch hydrolyzed to acetic acid under alkaline conditions can affect the determination of sodium diacetate in quick-frozen prepared food.In order to test the interference of sodium diacetate in quick-frozen food,GB 5009.277-2016 ’National food safety standard determination of sodium diacetate in food’ was used to determine the content of sodium diacetate in two kinds of modified starch of acetic ester A-1 and acetyl diphosphate A-2.Acetylation of different substitution degrees of modified starch acetyl,sodium diacetate and acetic acid background content were tested at the same time.The results showed that acetate starch had a significant positive interference on the determination of sodium diacetate in food after acetylation,and the amount of sodium diacetate in quick-frozen food was linearly correlated with the addition of modified starch.There was a significant positive correlation between the content of sodium diacetate in the modified starch and its acetylation substitution.In summary,the current national food safety standard GB 5009.277-2016 is not suitable for the determination of sodium diacetate in quick-frozen food which has acetate-modified starch.