Lettuce
Differences between film wrapped and non wrapped lettuce were only found in the insoluble pectin fraction after 4 days of shelf life. Insoluble pectin increased in non wrapped lettuce in comparison to the control, whereas no effect was detected in the film wrapped variant (Table 1). This effect was assumingly due to an CO2 enrichment and O2 degradation within the film and might have led to a desired inhibition of pectolytic en- zyme activity being responsible for cell wall degradation (Kanellis, Solomos, & Roubelakis-Angelakis, 1991; Merodio, 1993). According to clinical studies a decrease in the cholesterol level is caused by water soluble dietary fibers, e.g. water soluble pectin (Elmadfa & Leitzmann,
1998). In respect to diet physiological concerns film wrapping was found not to be beneficial for maintaining