Faculty of Food Technology and Biotechnology, University of Zagreb
Abstract
Some by-products of wine industry still contain nutrients and functional compounds that make them potential ingredients to formulate new high value-added food products. The aim of this study is to develop milk fermented with Lactobacillus acidophilus fortified with marc flour of different cultivars of Vitis vinifera from wine production and to evaluate their influence on fermentation kinetics, probiotic counts, phenolic compounds, sugar content and antioxidant activity. The acidification time was significantly shortened by these enrichments (by up to 2.7 h), and the bacterial count during cold storage resulted in stronger fortification of samples (up to 4.13 %) when compared to control tests. Fermented milk containing grape marc showed considerable amounts of phenolic compounds with notable antioxidant activity, as well as significant amounts of total sugars. The most important aspect of this paper is the feasibility of using winery by-products, rich in phenolic compounds, as natural supplements to fortify probiotic-fermented milk.Neki nusproizvodi u proizvodnji vina sadržavaju hranjive i funkcionalne tvari, pa se mogu upotrijebiti za razvoj novih prehrambenih proizvoda s dodanom vrijednošću. Svrha je ovoga rada bila proizvesti mlijeko obogaćeno mljevenom kominom različitih sorata grožđa i fermentirano s pomoću bakterije Lactobacillus acidophilus, te odrediti utjecaj dodatka komine na kinetiku fermentacije, broj probiotičkih mikroorganizama, udjele fenolnih spojeva i šećera, te antioksidativnu aktivnost fermentiranog mlijeka. Vrijeme fermentacije obogaćenog mlijeka znatno se smanjilo (do 2,7 h), a broj bakterija tijekom skladištenja u hladnjaku povećao (do 4,13 %) u usporedbi s kontrolnim uzorkom. Fermentirano je mlijeko obogaćeno mljevenom kominom grožđa imalo veće udjele fenolnih spojeva i ukupnih šećera, te izraženiju antioksidativnu aktivnost. Najveći je značaj ovog istraživanja u tome što dokazuje da se nusproizvodi vinske industrije bogati fenolnim spojevima mogu upotrijebiti kao prirodni dodaci mlijeku fermentiranom s pomoću probiotika
