Valorizacija proizvoda fermentacije kombuhe na otpadnom toku iz proizvodnje vina

Abstract

U poslednjoj deceniji, uočava se rast popularnosti proizvodnje i konzumacije hrane isključivo prirodnog porekla. Jedan od pravaca ovog razvoja je funkcionalna hrana, koja zahvaljujući svojim oso-binama smanjuje rizik od pojave različitih negativnih uticaja na zdravlje potrošača. Razvoj funkcionalnih, probiotskih napitaka koji nisu na mlečnoj osnovi je sve interesantniji i može se očeki-vati da će ovaj segment tržišta u budućnosti značajno rasti. U ovu grupu namirnica spada i kombuha napitak. U okviru ove doktorske disertacije ispitivana je mogućnost pri-mene efluenta dobijenog nakon bistrenja šire metodom flotacije u procesu proizvodnje belog vina sorte Rizling kao sirovine za do-bijanje kombuha napitka. Početnim ispitivanjima utvrđena je spo-sobnost kombuha kulture da fermentiše korišćeni supstrat, nakon čega su optimizovani uslovi kultivacije variranjem početnog sadr-žaja šećera (30, 50 i 70 g/L), temperature (20, 25 i 30 °C) i trajanja (3, 6 i 9 dana) bioprocesa. Takođe, rađena je hemijska, mikrobio-loška i antioksidativna karakterizacija dobijenog proizvoda. Kao najpogodnije vreme trajanja fermentacije, senzornom analizom, određeno je tri dana. Analizom antimikrobne aktivnosti utvrđen je značajan potencijal inhibicija rasta i Gram pozitivnih i Gram ne-gativnih bakterija. Antioksidativni potencijal novog tipa kombuha napitka bio je veoma izražen, a utvrđeno je prisustvo različitih organskih i fenolnih kiselina, pored visokog sadržaja ukupnih fe-nola. Prisustvo vitamina C je utvrđeno u svim konzuminim uzor-cima. Proizvodnja biomase bila je značajno uvećana u odnosu na uobičajene vrednosti za kombuha fermentaciju

Last decade has brought a noticeable increase in production and consumption popularity of the food of purely natural origins. One of the development directions is the new functional food, which reduces risk of the various hazardous health effects, thanks to its properties. Development of functional probiotic beverages, other than milk-based is becoming more popular, and this market nicheis expected to grow further. Kombucha beverage belongs to this group of the food products. This thesis investigates possible usage of the Riesling white wine production effluent as the raw material for kombucha fermenta-tion. The effluent is obtained after grape must clarification per-formed by flotation. Initial experiments confirmed kombucha’s ability to ferment this substrate. Further, fermentation conditions were optimized by varying initial sugar level (30, 50, and 70 g/L) and temperature (20, 25, and 30 °C), as well as duration of the fermentation (3, 6, and 9 days). Chemical, microbiological, and antioxidative characterisation of the novel product was performed. By sensory analysis, most suit-able fermentation time was set at three days. By antimicrobial analysis, inhibitory potential towards Gram-positive and Gram-negative bacteria is determined. Antioxidative potential of the new kombucha product was very pronounced. Also, various organic and phenolic acids were found to be present, along with high phe-nolic content. Vitamin C was detected in all consumable samples. Biomass production was significantly higher compared to typical kombucha fermentation.