Studies on functional barriers to migration: Use of model substances to investigate transfer from paper and board packaging to food

The levels of soluble sugars, starch, pectin and insoluble fibre in blanched green beans, green beans and Padrón peppers were monitored during 12 months' deep-freezing. Blanching did not alter the pectin content of the beans, but reduced their soluble sugar and starch contents by 10 and 8%, respectively. Nonetheless, levels of all these components of both vegetables were stable during deep-freezing. Blanching increased the insoluble fibre (IF) content of green beans by 45%, thereby favouring hardening of the bean tissue and negatively affecting its organoleptic properties. Deep-freezing for periods longer than one month, especially in combination with vaccum packing, also increased the IF content of blanched beans, and likewise those of unblanched beans and Padrón peppers.