蚕蛹壳聚糖/中药复合浸涂液对草莓的保鲜效果

Effect of Silkworm Pupa Chitosan and Herbal Medicine Composite Coating Solution on Fresh-keeping of Strawberry

以蚕蛹壳聚糖作为主要材料,分别添加不同中药提取液作为抗菌剂制备复合浸涂液用于草莓的保鲜。以未浸涂的草莓为空白对照组,分别以壳聚糖(A组)、壳聚糖+金银花(B组)、壳聚糖+芦荟(C组)、壳聚糖+鱼腥草(D组)复合浸涂液浸涂草莓,在室温下每隔2 d测定草莓的腐烂指数、失水率、可滴定酸含量和维生素C(VC)含量等。浸涂保鲜试验第6天,对照组草莓的腐烂指数为4,完全腐烂,而A、B、C、D处理组草莓的腐烂指数分别比对照组下降了17%、54%、54%、15%;第4天后,各处理组的草莓与对照组相比失水率显著下降,其中C组第10天的失水率降低了最多,与对照组相比降低了27%;对照组第6天草莓中的可滴定酸质量分数为0.1%,A、B、C、D处理组分别比对照组升高了46%、138%、185%、53%;对照组第6天草莓中的VC质量比为450 mg/kg,A、B、C、D处理组分别比对照组升高了12.5%、37.8%、42.2%、17.8%。结果表明:家蚕蛹壳聚糖/中药复合浸涂液各处理组草莓的保鲜指标均优于对照组,差异达极显著水平(P<0.01),对草莓有较好的保鲜效果。

In present study, silkworm pupa chitosan was used as the main material and extractions of different herbal med- icines were used as anti-microorganismal agent to prepare composite coating solution for fresh-keeping of strawberry. Tak- ing non-coating as the blank control （CK）, composite coating solution containing chitosan （group A）, chitosan ＋ Lonicera japonica （group B）, chitosan ＋Aloe （group C）, and chitosan ＋ Houttuynia cordata （group D） was used to dip and coat strawberry samples, respectively. The rotten index, water loss rate, content of titratable acids, and vitamin C （VC） con- tent of the strawberry samples were determined every other day at room temperature. The results showed that, on the 6th day, the rotten index of strawberries in CK was 4 （completely rotten）, while that in groups A, B, C and D was reduced by 17%, 54%, 54%, and 15% compared to that of CK, respectively. Compared with CK, water loss rate of strawberries in other treatment groups significantly declined on the 4th day, among which the decline of water loss rate of group C was the highest on the 10th day, being decreased by 27% compared to that of CK. On the 6th day, the mass fraction of titratable acids in CK was 0. 1%, and that in groups A, B, C and D was 46%, 138%, 185% and 53% higher than that of CK, re- spectively. At the same time, the mass ratio of VC in CK was 450 mg/kg, and that in groups A, B, C and D was 12. 5%, 37.8%, 42.2% and 17.8% higher than that of CK, respectively. These results showed that the fresh-keeping indexes ofstrawberries in different groups treated with composite coating solution containing silkworm pupa chitosan and herbal medicines were all superior to the control group. The differences reached extremely significant level （P 〈 0. 01 ）, showing good fresh-keeping effect to strawberry.