纳米TiO_2/玉米淀粉复合涂膜对圣女果保鲜效果的研究

Fresh-Keeping Effect of Nano-Titania/Corn Starch Compound Coating on Cherry Tomato

通过高效分散剂和超声波分散技术,将纳米TiO2均匀分散在玉米淀粉涂膜液中,对圣女果进行涂膜处理,探讨其对贮藏过程中果实失重率、可溶性固形物含量、硬度、腐烂率、VC含量及总酸含量变化的影响,以研究纳米TiO2/玉米淀粉复合涂膜液对圣女果涂膜保鲜的效果。结果表明:随着复合涂膜液中纳米TiO2用量的增加,圣女果的失重率、可溶性固形物含量和腐烂率是先减小后增大,而硬度、VC含量和总酸含量则呈现先增大后减小的变化规律。纳米TiO2用量为0.025%(m/m,以玉米淀粉的质量为基准)时的保鲜效果最好,涂膜后的圣女果在室温(25℃)贮藏11d,其失重率、可溶性固形物含量、腐烂率分别比对照组降低了28.6%、12.7%、78.8%,硬度、VC含量、总酸含量分别是对照组的1.33、1.12、1.34倍。说明纳米TiO2在水果涂膜保鲜方面具有一定的应用前景。

Polyvinyl pyrrolidone（PVP）,a highly effective dispersant,and ultrasonic technique were used for the homogeneous dispersion of nano-titania in corn starch paste to yield a compound coating.The coating was used to treat cherry tomato and the weight loss,the contents of soluble solids,VC and total acid,hardness and percentage of rotten fruits of treated cherry tomato during storage were periodically measured in order to investigate its fresh-keeping effect.The results showed that with increasing amount of added nano-titania,weight loss,soluble solid content and percentage of rotten fruits first decreased and then increased,but hardness and the contents of VC and total acid displayed an opposite change pattern.The compound coating with added nano-titania at 0.025%（m/m,on the basis of the dry weight of corn starch） showed the best fresh-keeping effect on cherry tomato;the weight loss,soluble solid content and percentage of rotten fruits of cherry tomato treated with it after 11 days of storage were reduced by 28.6%,12.7% and 78.8%,respectively,when compared with untreated cherry tomato,whereas hardness and the contents of VC and total acid exhibited 1.33-,1.12-and 1.34-fold increases,respectively.Our findings suggest that nano-titania appear to have the potential to be applied for the fresh-keeping of fruits.