The temperature influence on the flavonoid content of the
native apple peel extract and 0.3 g dissolved extract in 100mlwater
was studied at 50 C and 95 C. Approximately 5 mg of dry native
extract or 5ml dissolved extract, respectively, were filled into 20 ml
GC-Vials which were then tightly sealed. The vials were kept in a
water bath at 50 C and 95 C in the dark for 15 h. The apple peel
extract was dissolved in water after the temperature influence. All
samples were analyzed directly by using HPLC-DAD. To study the
shelf life of the freeze dried end product, apple chips were stored at
20 C and 40 C for 12 months in sealed bags (OPA 15 mm e LDPE
15 mme Aluminum 12 mme LDPE 20 mm) under light exclusion and
the quercetin glycoside levels were determined. Three replicates of
the experiments were performed.