四种蔬菜固体保鲜剂对黄瓜的保鲜效果研究

Microencapsulation Optimization of Essential Oils from Four Varieties of Plants and Their Fresh-keeping Effect on Cucumbers

研究蔬菜固体保鲜剂的保鲜效果。采用丁香、花椒、大蒜、生姜4种天然香辛料精油,通过微胶囊技术分别制成挥发性保鲜剂,让其挥发性释放于黄瓜表面,于常温(25℃±5℃)条件下贮藏30d,定期测定黄瓜的腐烂率、失重率、呼吸强度、总糖和叶绿素含量并观察其变化规律。结果表明:4种天然香辛料精油制成的保鲜剂对黄瓜都有显著的保鲜效果,其中用丁香精油制成的保鲜剂保鲜效果最好,花椒次之,大蒜保鲜效果最差。

The essential oils from clove,garlic,ginger and pepper were separately microencapsulated using a mixture of gum arabic and maltodextrin as wall material and a mixture of Span 80 and Tween 20 as emulsifier to prepare solid preservatives.The optimal ratio of Span 80 to Tween 20 was determined to be 1：2.The key process conditions including maltodextrin-to-gum Arabic ratio,emulsifier amount,core material-to-wall material ratio and CaCl2 amount for the microencapsulation of clove,garlic,ginger and pepper essential oils were optimized using orthogonal array design.Cucumbers were treated with each of four microcapsules obtained under optimized conditions,fumigated in the presence of 0.06% 1-MCP for 2 days and stored at room temperature for 30 days,and the percentage of rotten fruits,weight loss,respiratory intensity,total sugar content and chlorophyll content of cucumbers were determined at 6-day intervals during storage.It was found that microencapsulated clove,garlic,ginger and pepper essential oils all presented remarkable fresh-keeping effect on cucumbers and that the fresh-keeping effect of microencapsulated clove essential oil was the best,followed by microencapsulated pepper and garlic essential oils.