茶多酚/海藻酸钠膜对鲜切猕猴桃品质的影响

Effect of Tea Polyphenol-containing Sodium Alginate-based Edible Coatings on the Quality of Fresh-cut Kiwifruit

为了延长鲜切猕猴桃的货架期和保持其新鲜品质,本试验研究了不同浓度茶多酚/海藻酸钠涂膜处理对(4±0.5)℃贮藏鲜切猕猴桃的可溶性固形物、色泽、总叶绿素、抗坏血酸、总酚和细菌总数的影响。试验分为对照组(Control),海藻酸钠处理组(T0),1.0%茶多酚/海藻酸钠组(T1),1.5%茶多酚/海藻酸钠组(T2)和2.0%茶多酚/海藻酸钠组(T3)。结果显示,在(4±0.5)℃贮藏12d,T0处理可减缓可溶性固形物含量和总叶绿素含量降低的速度,对鲜切猕猴桃的L*值和a*值无显著影响。T1、T2和T3处理可显著抑制抗坏血酸含量和总酚含量的下降,并显著降低鲜切猕猴桃表面的细菌总数(TPC),使TPC在贮藏12 d时保持在106 CFU/g以内。然而,T2和T3处理显著降低了猕猴桃片的L*值和a*值。研究结果表明,当膜液中茶多酚的质量分数为1.0%时,可较好的保证鲜切猕猴桃的品质。

In order to extend the shelf-life and maintain the quality of fresh-cut kiwifruit, the effects of different concentrations of tea polyphenols incorporated into a sodium alginate-based edible coating on the soluble solid content, color, total chlorophyll content, ascorbic acid content, total polyphenol content, and total bacterial count of fresh-cut kiwifruit （stored at 4 ± 0.5 ℃） were evaluated. The various groups used in the experiment were the control, sodium alginate-treated （TO）, sodium alginate coating containing 1.0% （m/V） of tea polyphenol （T1）-treated, sodium alginate coating containing 1.5% （m/V） of tea polyphenol （T2）-treated, and sodium alginate coating containing 2.0% （m/V） of tea polyphenol （T3）-treated groups. The results showed that the TO treatment could slow down the decrease of the soluble solid content and total chlorophyll content, but had no significant impact on the L＊ and a＊ values. T1, T2, and T3 treatments could, apparently, stop the decline of ascorbic acid and total polyphenol content, significantly reduce the total plate count （TPC） on the surface of fresh-cut kiwifruit, and limit the TPC to within 106 CFU/g after 12-day storage. However, T2 and T3 treatments significantly decreased the L＊ and a＊ values of fresh-cut kiwifi-uit. In conclusion, when the mass fraction of tea polyphenol in the sodium alginate coating was 1.0%, a good quality of fresh-cut kiwifruit could be maintained.