Kinetics of non-enzymatic browning in hemi-dried litchi fruits during 11 weeks were investigated. Hemi-dried litchi fruits were stored at -20℃,3 ℃ or 40℃. Color changes were assayed by browning index (A280nm,A420nm) and the CIE-Lab color system. Browning level of hemi-dried litchi fruits stored at different temperatures with vacuum and no-vacuum packages increased according to a zero-order reaction kinetic. Activation energy for it was 54.51 J/mol and 52.17 J/mol,respectively. And color formation(△ E) followed zero-order reaction kinetic,too. Activation energy was 38.49 J/mol and 38.41J/mol,respectively.5-(hydroxymethyl)-2-furfural(5-HMF) concentration,in hemi-dried litchi fruits ranged from 78.63 to 2050.49 μg/5 g according to storage temperature changes. Package form was not the main factor of affecting color formation and 5-HMF accumulation during storage period of hemi-dried litchi fruits. Evaluated from the color of products,the hemi-dried litchi fruits would lose their commercial value when they are stored for over 4 weeks at room temperature.%研究了半干型荔枝干在-20、3、40℃贮藏11周中的非酶褐变动力学,利用褐变指数和CIE-Lab色泽系统测定贮藏期间的色泽变化,用真空包装与非真空包装的半干型荔枝干贮藏在不同温度下,其褐变符合零级反应动力学,反应活化能分别是54.51J/mol和52.17J/mol;色泽的形成也符合零级反应动力学,反应活化能分别是38.49J/mol和38.41J/mol.依不同贮藏温度,半干型荔枝干中5-HMF的浓度从78.63到2050.49μg/5g.真空包装与否不是影响色泽变化与5-HMF积累的主要因素.在常温下贮藏超过4月,从色泽考虑,半干型荔枝干的商品价值降低.
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