Quality Evaluation and Multi-Criteria Optimization of Cookies Fortified with Lyophilized Black Goji

Abstract

Lyophilized black goji berry powder (LBGBP) cultivated in Serbia was evaluated and optimized as a fortification agent in cookie formulation. Nutritional, chemical, technical and biological characteristics, in vitro release and storage stability were analyzed. LBGBP is characterized by a phenolic-rich profile dominated by acylated anthocyanins, 5-O-caffeoylquinic acid (5-O-CA), and spermidine-based phenylamides (S1, S2), which are partially retained in LBGBP-enriched cookies and enhance their functional properties. The substitution of different white flour shares with LBGBP in cookies statistically significantly improved their overall nutritional profile by increasing protein, dietary fiber, minerals and bioactive compounds, concurrently reducing fat, sugar and sodium levels. With the increase in the LBGBP in cookies, total phenolics and total anthocyanin content increased to the levels of 58.09 mg GAE/100 g and 10.12 mg CGE/100 g of cookies, respectively. The overall effect of LBGBP cookie fortification led to softer, more crumbly cookies with significant improvement in antioxidant and antidiabetic activity. The Z-score analysis was chosen to perform multi-criteria cookie formulation optimization with the goal of maximal functional enrichment, with minimal decrease in technological quality. The 10% LBGBP substitution was calculated to produce optimal overall quality, obtaining 65.96% of maximal score in comparison to the control sample of only 32.91%.