渗透方式对真空冷冻干燥芒果细胞结构及品质的影响

Effect of Osmotic Method on Cell Structure and Quality of Vacuum Freeze-dried Mango

为探索渗透方式对冻干芒果细胞结构及品质的影响,本实验以玉芒为原料,在环境温度(20、30℃)下采用蔗糖固态渗透(SSD)、液态渗透(LOD)方式处理芒果后再进行真空冷冻干燥,通过测定渗透方式处理后芒果鲜样可溶性固形物、细胞形态以及分析冻干芒果的弹性模量、孔隙度、细胞壁结构、色泽以及V_(C)、总酚、β-胡萝卜素保留率指标的变化。结果表明:固态渗透芒果可溶性固形物增加量高于液态渗透,液态渗透处理的芒果细胞形态与鲜样(CK)无明显差异,固态渗透随蔗糖添加量的增加可溶性固形物含量和细胞形态皱缩程度增加;固态渗透减少细胞间孔隙度提高芒果弹性模量;傅里叶变换红外光谱结果表明O-H的伸缩震动吸收峰,随着蔗糖添加量的增加,吸收峰强度逐渐增加;低蔗糖固态渗透有利于维持芒果色泽;在环境温度20和30℃条件下固态渗透处理的真空冷冻芒果V_(C)和总酚的保留率高于液态渗透,其中固态渗透SSD20的V_(C)和总酚保留率最高分别为37.75%、33.37%;固态渗透SSD20处理的真空冷冻芒果的β-胡萝卜素保留率高于液态渗透LOD30,但固态渗透随蔗糖添加量的增加,β-胡萝卜素的保留率逐渐下降。本研究结果发现低蔗糖固态渗透可以有效提高真空冷冻芒果的综合品质,为改善芒果干燥制品品质提供理论参考。

This study aimed to explore the effect of osmotic methods on the cell structure and quality of freeze-dried mango.This experiment uses jade as the raw material,mango was treated by solid osmotic(SSD)and liquid osmotic(LOD)at 20 and 30℃,and then vacuum freeze-dried.By measuring the soluble solids and cell morphology of fresh mango samples after osmosis treatment,and analyzing the changes of elastic modulus,porosity,cell wall structure,color and V_(C),total phenols,and β-carotene retention index of freeze-dried mangoes.The results showed that the increasing of soluble solids in solid osmotic mango was higher than that in liquid osmotic.There was no significant difference between the cell morphology of liquid osmotic mango and fresh sample(CK).The content of soluble solids and the shrinkage degree of cell morphology increased with the increasing of sucrose,the solid osmotic reduced the intercellular porosity and increased the elastic modulus of mango.Moreover,results of infrared spectroscopy showed that the stretching vibration absorption peak of O-H increased with the increasing of sucrose content.Low sucrose solid osmotic helps to maintain the color of mango.The retention rates of V_(C) and total phenol in solid osmotic were higher than those in liquid osmotic at ambient temperature of 20 and 30℃,and the highest retention rates of SSD20 V_(C) and total phenol in solid state infiltration were 37.75% and 33.37%,respectively.The retention rate of β-carotene in vacuum freeze-dried mango SSD20 treated with solid osmotic treatment was higher than that of liquid osmotic treatment LOD30,but the retention rate of β-carotene decreases gradually with the increasing of sucrose supplementation in solid osmotic treatment.The results of this study showed that low sucrose solid osmotic could effectively improve the comprehensive quality of vacuum freeze-dried mango,which would provide a theoretical reference for improving the quality of dried mango products.