Second life of berry by-products: laboratory investigation for applicative solution

In the postharvest phase fruit goes on towards the loss of quality. Perishability is actually a big problem for berries, due to their morphology and physiology, thus implementing the quality loss with respect to other major fruit. Postharvest technologies are improving every day to guarantee the longest quality maintenance of fruit, nevertheless, part of the production will always be discarded from the fresh market, mainly due to visual and colour defects and altered texture. Thus, waste is produced. The situation of blueberry and baby kiwi has been analysed. The objective of the research is the valorisation of the by-products from the packhouse proposing innovative and green solutions, also paying attention to the nutritional aspects. The upgrade of these wastes will consider also their geographical origin and the potential implementation and inclusion in the local production activities. Technologies such as drying, lyophilisation and spray-drying have been considered to obtain a snack or semi-finished product with multiple application possibilities, such as powders, additional ingredients or direct consumption. The characterisation of each product, starting from the raw material, will help in defining its role in recipes in terms of both technological and nutritional value. The main aspect emerged regards the colour of the product: drying, in fact, leads to the matrix browning and a deep change in the organoleptic characteristics. Textural changes also occurred according to the different water removal rates of each technology. Preliminary investigation of possible use as ingredient has been evaluated through water solubility index and water absorption capacity. As concerns about packaging may arise, water activity (aw) parameters have been considered. To conclude, the valorisation of damaged berries is interesting, but it is necessary to optimise the production, considering the utilization purpose and the economic aspect.