Title : Bioactive compounds and stability of fiber and protein enriched salted snacks by olive paste and brewer’s spent grain
Abstract:
This research project aims to formulate functional snacks through the upcycling of by-products from two production chains: the brewing and the olive oil production chains. The salted snacks were formulated by partially substituting wheat flour with brewers’ spent grains (BSGs) and olive paste (OP). OP is characterized by a well-balanced lipid profile, rich in mono and polyunsaturated fatty acids, and an interesting content of antioxidant compounds. BSGs are characterized by high fibre and protein contents and by the presence of antioxidant compounds, moreover, BSGs fat is rich in mono and polyunsaturated fatty acids. These characteristics make OP and BSGs particularly suitable as functional ingredients for the food industry and for the formulation of functional products. BSGs were added, accounting for 12% and 30%, both wet and dry, and OP was added, accounting for 8%, both pre-debittered and untreated. This study has underlined that replacing wheat flour with BSGs and OP allows for a significant increase in total dietary fibre, protein, and phenolic compounds compared with the reference snack. The fibre content allows for a “high in fibre” label, and the protein content for a “source of protein” label for all the tested recipes. The resulting snacks showed a reduction in total carbohydrates and sugars compared to 100% wheat flour snacks. The fat content of the functional snacks was higher than the control, although slightly richer in unsaturated fatty acids. The snack enriched with 30% dried BSGs and 30% of non-pre-debittered OP reached also the EFSA claim of being “high in unsaturated fat”. The formulation of snacks by partial substitution of wheat flour with BSGs and OP can be an efficient and feasible strategy for the valorization of these by- products throughout the production of functional food.
This research was funded by Italian Ministry of the Environment and Energy Security on the call for the co- financing of research projects aimed at the development of technologies for the prevention, recovery, recycling and treatment of waste not falling within the categories already served by supply chain consortia, the eco-design of products and the correct management of the related waste – 2021 edition (D.D. 9/12/2021, n. 83). CUP J93C22000330006.
