速冻荔枝果肉冻藏期间营养成分及色泽的变化研究

Nutrition and Color Changes during Frozen Storage of Litchi Flesh

摘要:

色泽是速冻荔枝果肉主要的质量指标之一，冻藏期间速冻荔枝果肉发生褐变会影响产品的商品价值。采用色差仪测定结果表明，速冻荔枝果肉在-60 ℃下冻藏，基本不会发生色泽变化；而在-18 ℃下冻藏的样品会发生轻微色泽变化。分析褐变重要的中间产物5-羟甲基糠醛(5-HMF)，结果也表明，速冻荔枝果肉在-60 ℃下冻藏，5-HMF基本没有变化；而在-18 ℃下冻藏的样品会有轻微减少。-18 ℃、-60 ℃冻藏期间，营养化学物质除了-18 ℃冻藏的还原糖有轻微减少外，基本没有发生变化。

Abstract:

Color is a major indicator of quality of frozen litchi pulp and frozen litchi pulp browning during frozen storage may affect the value of the goods. By colorimeter measurement, it was found that when strored below -60 ℃, no color change occured.Samples frozen at -18 ℃ showed a slight color change .Analysis of browning intermediates 5-(hydroxymethyl) furfural indicate that 5 - (hydroxymethyl) furfural in frozen litchi pulp at -60 ℃ unchanged,but slightly decreased when the samples was frozen at -18 ℃. During storage at -18 ℃ and at -60 ℃, no changes were found in nutrition chemicals content except for reducing sugar at -18 ℃.