二氧化硫(SO2)熏蒸改善木纳格葡萄的采后品质

为探讨SO2熏蒸对木纳格葡萄采后品质及质地变化的影响,测定葡萄果实贮藏期品质指标参数;采用质地多面分析法(TPA法)测定木纳格葡萄果实质地参数,通过相关性分析对质地参数进行分析。结果表明:SO2熏蒸浓度为3000μL/L时,果实中SO2残留量为7.55mg/kg,符合欧美发达国家鲜食葡萄进出口食品标准。SO2熏蒸处理的葡萄果梗、果柄褐变度比未进行熏蒸处理降低了2.60%;SO2处理能抑制果梗、果柄的叶绿素分解,未经SO2处理的果梗叶绿素含量从0.091 mg/g降低至0.037 mg/g,经过SO2处理的果梗叶绿素含量降低至0.052 mg/g,具有显著性差异(p<0.05)。SO2熏蒸处理能维持葡萄采后可溶性固形物和可滴定酸含量稳定,保持葡萄采后品质。可溶性固形物含量达到最大值时,SO2熏蒸处理比未处理高4.2%;贮藏结束时,SO2处理的可滴定酸含量比未处理果实高11.60%。采用TPA法测定SO2处理后木纳格葡萄果实的质地参数,发现SO2处理能较好的保持葡萄果实的各项质地参数:果实硬度在贮藏结束时为4.29N/cm2,硬度下降减缓;内聚性在贮藏结束时为0.78,具有显著性差异(p<0.05);弹性、胶黏性和咀嚼性分别比贮藏时(0 d)下降了3.8%、18.1%和3.68%。SO2熏蒸处理后果实各项质地参数与品质之间的相关性分析表明,果实质地参数可以较好的评价木纳格葡萄果实采后贮藏期间的品质。通过以上实验结果,明确了3000μL/L SO2短时熏蒸处理能较好的保持木纳格葡萄采后品质。

Improving on Postharvest Quality of Munag Grape Berries Fumigated by Sulfur Dioxide (SO2)

In order to investigate the effect of postharvest quality and texture characteristics changes of munag grape after fumigation by SO2, the changes of fruit quality indexes during storage were determined. Texture parameters of munag grape were determined by Texture multifaceted analysis(TPA method) and studied by correlation analysis. The results showed that when the fumigation concentration of SO2 was 3000 μl/L, the residue of SO2 in the fruit was 7.55 mg/kg, which is in line with the developed countries in Europe and America on table grape import and export food standards. The browning degree of grape stem and stalk after SO2 fumigation was 2.60% lower than that without fumigation. SO2 fumigation treatment could inhibit chlorophyll decomposition. Its content in stems decreases from 0.091 mg/g to 0.037 mg/g without SO2 fumigation treatment, while decreases to 0.052 mg/g after SO2 fumigation treatment, showing a significant difference(p<0.05). SO2 fumigation treatment could keep the content of soluble solid and titratable acid stable, maintaining postharvest quality of grapes. When the soluble solid content reached the maximum value, SO2 fumigation treatment was 4.2% higher than untreated. At the end of storage, the titratable acid content of SO2 treated fruits was 11.60% higher than that of untreated fruits. TPA method was used to determine the texture parameters of the fruit after SO2 treatment, and it was found that SO2 treatment could well maintain the texture parameters of the fruit. The fruit firmness decreased slowly and was 4.29 N/cm2 at the end of storage. At the end of storage, the cohesiveness was 0.78, showing a significant difference(p<0.05). Elasticity, gumminess and chewiness decreased by 3.8%, 18.1% and 3.68% respectively compared with that at 0 d. The correlation analysis between texture parameters and quality of fruits after SO2 fumigation showed that the texture parameters of fruits could well evaluate the quality of fruits in post-harvest storage. Through the above experimental results, it was clear that 3000 μL/L of SO2 short time fumigation could maintain the quality of munag grape.