The use of glass transition temperature in forecasting of whey powder storage stability, obtained with the use of electro-spark treatment

Abstract

This study investigated the behavior during storage of dry whey obtained using different approaches that prevent caking (adding silicon dioxide, electro-spark treatment of whey). Forecasting the stability of quality whey powder was carried out based on a glass transition temperature.We showed that the highest glass transition temperature (+18.5 °С) and, subsequently, smallest difference between product temperatures and glass transition temperature were discovered in dry whey, obtained with the use of electro-spark treatment, which proves its stability while in storage.We found that the other samples of dry whey under normative storing terms (from 0 till 20 °С) are predominantly in rubbery state, which can negatively influence on stability of the product while in storage. Based on the glass transition temperature we determined that electro-spark treatment in technology of whey powder allowed reaching anti-caking effect due to physicochemical processes resulting from electro-spark charges. This was proved by calculationstickiness and caking sensibility index and the degree of caking (to 2 %).