【摘要】 研究了红枣汁热处理时,含水量、加热温度和时间、小分子糖、氨基酸、pH、金属离子等主要因素对5-羟甲基糠醛(5-HMF)的影响,探索红枣汁非酶褐变规律.结果表明:热处理红枣汁时,含水量越高,5-HMF生成越少;加热温度的升高及加热时间的延长均可致红枣汁非酶褐变指数及5-HMF值增大;还原性果糖、葡萄糖和麦芽糖较非还原性蔗糖更能促进5-HMF的生成,果糖最强,其次为葡萄糖;半胱氨酸和天冬氨酸有抑制5-HMF的生成作用,甘氨酸和赖氨酸有促进5-HMF的生成作用;pH为6(枣汁自然pH)的红枣汁热处理时5-HMF含量最低,pH为8时(强碱性)最高;Ca2+能减少红枣汁热处理时的5-HMF生成,Cu2+和Fe3+能促进5-HMF生成.更多还原

【Abstract】 The effects of water content,heating temperature and time,micromolecule sugar,amino acid,pH value,and metallic ion on 5-HMF of Chinese jujube juice during thermal processing are studied,and the rule of nonenzymatic browning of Chinese jujube juice is searched.The results showed that higher moisture content is,less 5-HMF generate during thermal processing;rising of temperature and extension of time all can cause the increase of non-enzymatic browning index and content of 5-HMF.The effect of reducibility fructose,glucose,maltose to accelerate the generation of 5-HMF is higher than that of irreducibility sucrose,cysteine and aspartate can inhibit the generation of 5-HMF,glycine and lysine can accelerate the generation of 5-HMF;when pH value is 6(natural pH value for jujube juice),the content of 5-HMF is lowest,when pH value is 8,the content of 5-HMF is highest;Ca2+ can reduce the generation of 5-HMF,while Cu2+ and Fe3+ can accelerate the generation of 5-HMF.更多还原