Slađana Stajčić

Sour cherry pomace extract encapsulated in whey and soy proteins: Incorporation in cookies.

One of the potential sources of valuable bioactives is pomace, a by-product from fruit juice processing industry. In the presented study, bioactive compounds extracted from cherry pomace, encapsulated in whey and soy proteins, have been incorporated in cookies, replacing 10% (WE10 and SE10) and 15% (WE15 and SE15) of flour. Total polyphenols, anthocyanins, antioxidant activity and colour characteristics of enriched cookies were followed during 4 months of storage. Total polyphenols of WE10, SE10, WE15 and SE15 have shown a slight increase (23.47, 42.00, 4.12 and 1.16%, respectively), while total anthocyanins (67.92, 64.33, 58.75 and 35.91%, respectively) and antioxidant activity (9.31, 24.30, 11.41 and 12.98%, respectively) decreased. Colour parameters (L(∗), a(∗) and b(∗)) of cookies were influenced by the colour of encapsulates. Fortified cookies received satisfactory sensory acceptance as well. Encapsulated sour cherry pomace bioactives have positively influenced functional characteristics of fortified cookies and their preservation.

Chemical composition and potential bioactivity of strawberry pomace

This study has been designed to screen phenolic compounds of strawberry pomace obtained from two strawberry cultivars, ‘Clery’ (SC) and ‘Marmolada’ (SM), and their biological activity (O2˙−, ˙OH, DPPH˙ and ABTS+˙ antioxidant capacity, α-glucosidase inhibition and reducing power). The SM pomace contained significantly higher (p < 0.05) amounts of total flavonoids and anthocyanins, individual phenolic acids and flavonoids, among them protocatechuic acid, catechin and pelargonidin-3-glucoside (1838.31 and 1646.68 per 100 g DW, respectively) being the most abundant. The SM pomace showed higher DPPH˙ and ABTS+˙ antioxidant capacities and reducing power, as well as higher activity towards O2˙− , ˙OH (EC50˙OH = 2.77 mg mL−1) and α-glucosidase inhibitory potential (ECα-GIP50 = 1.16 mg mL−1). Our results support the use of strawberry pomace as a rich source of phytochemicals for further utilization in the food industry as supplements or ingredients for food fortification.

Encapsulation of Beetroot Pomace Extract: RSM Optimization, Storage and Gastrointestinal Stability

One of the great problems in food production are surplus by-products, usually utilized for feeding animals and for preparation of dietary fibre or biofuel. These products represent potential sources of bioactive antioxidants and colour-giving compounds which could be used in the pharmaceutical industry and as food additives. In the present study beetroot pomace extract was encapsulated in soy protein by a freeze drying method. Process parameters (core: wall ratio, extract concentration and mixing time) were optimized using response surface methodology (RSM) in order to obtain the optimum encapsulate (OE) with the highest polyphenol encapsulation efficiency (EE) and radical scavenging activity on DPPH radicals (SA). Using the calculated optimum conditions, the EE (86.14%) and SA (1668.37 μmol Trolox equivalents/100 g) of OE did not differ significantly (p < 0.05) from the predicted ones. The contents of total polyphenols (326.51 mg GAE/100 g), flavonoids (10.23 mg RE/100 g), and betalains (60.52 mg betanin/100 g and 61.33 mg vulgaxanthin-I/100 g), individual content of phenolic compounds and betalains by HPLC, and the ability to reduce Fe3+ ions, i.e., reducing power (394.95 μmol Trolox equivalents/100 g) of OE were determined as well. During three months of storage at room temperature, polyphenol retention was much higher (76.67%) than for betalain pigments, betacyanins (17.77%) and betaxanthins (17.72%). In vitro digestion and release of phenolics from OE showed higher release rate in simulated intestinal fluid than in gastric fluid. These results suggest encapsulation as a contemporary method for valorisation of sensitive bioactive compounds from food industry by-products.

8 – Patent Survey

Agro-industrial waste derived from fruit and vegetable processing presents a cheap source of phytochemicals and other valuable ingredients that have the potential to be reutilized. Winemaking has been one of the most important industries of many countries, with the trend of popularization. Grapes are known to be rich in polyphenols, which are not fully extracted/transferred to wine. This fact makes grape processing by-products an interesting source for further exploitation. Since polyphenols have been documented to have various beneficial health effects, grape by-products have the potential to be used in different applications, such as in functional food, dietary supplements, pharmaceutical and cosmetic products. Beside polyphenols, other potentially valuable ingredients of grape processing by-products include fatty acids, tocopherols, dietary fiber, proteins and tartarates. In order to commercialize the recovery of these beneficial ingredients from grape by-products, intellectual property rights of processes and ideas must be protected through patenting. The aim of this chapter is to present a survey of patent describing recovery process and applications, as well as health benefits claimed for grape by-products and to discuss the future perspectives.