Iskorišćenje otpadnog pivskog kvasca za inkapsulaciju bioaktivnih komponenata hrane

Abstract

Otpadni pivski kvasac (OPK) (engl. Spent brewer’s yeast, SBY) drugi je najvažniji nusproizvod industrije piva nakon pivskog tropa. Premda se neki kvasci mogu koristiti više puta za fermentaciju sladovine, nastala biomasa se na kraju proizvodnog procesa odbacuje, što dalje uzrokuje finansijske i ekološke probleme. U cilju smanjenja otpada ovog nusproizvoda agroindustrije, OPK se uglavnom koristi kao stočna hrana i kao takav ima nisku komercijalnu vrednost. Međutim, zbog svoje visoke nutritivne vrednosti, visoke dostupnosti i niske cene, OPK ima potencijal za profitabilnije primene, između ostalog, i za inkapsulaciju bioaktivnih jedinjenja. Sastav ćelijskog zida kvasca omogućava inkapsulaciju i hidrofilnih i lipofilnih bioaktivnih supstanci, dok njegova mehanička svojstva pružaju zaštitu od spoljnih faktora tokom obrade, skladištenja i konzumiranja. Proces inkapsulacije primenom otpadnog pivskog kvasca je jednostavan i rezultuje visokom efikasnošću inkapsulacije, koja se dodatno može poboljšati različitim predtretmanima kvaščevog materijala. Jedinjenja do sada uspešno inkapsulirana u OPK i materijale dobijene iz OPK uključuju polifenole, vitamine, ulja, pa čak i probiotike. U pogledu mogućih primena, OPK inkapsulati imaju veliki potencijal za upotrebu u prehrambenoj industriji; mogu se koristiti u formulaciji funkcionalne hrane ili kao zdrava zamena za sintetičke konzervanse i/ili boje. Ipak, povišeni troškovi proizvodnje i, u nekim slučajevima, gorčina inkapsulata mogu predstavljati izazov kada je u pitanju šira primena ove tehnologije i stoga bi trebalo da budu u fokusu budućih studija.

Spent brewer’s yeast (SBY) is the second most important by-product in the brewing industry after spent grain. Although some yeasts can be used multiple times to ferment wort, the resulting biomass is discarded at the end of the production process, causing financial and environmental problems. To reduce the waste of this agro-industrial by-product, SBY is mainly used as animal feed and as such has a low commercial value. However, due to its high nutritional value, high availability, and low cost, SBY has the potential for more profitable applications, including encapsulation of bioactive compounds. The composition of the yeast cell wall allows for the entrapment of both hydrophilic and lipophilic bioactives, and its mechanical properties provide protection from external factors during processing, storage, and consumption. The encapsulation process with spent brewer's yeast is simple and leads to high encapsulation efficiency, which can be further improved by various pretreatments of the yeast material. Compounds that have been successfully encapsulated in SBY and SBY-derived materials to date include polyphenols, vitamins, oils, and even probiotics. In terms of possible applications, SBY encapsulates have great potential for the food industry; they can be used to develop functional foods or as healthy substitutes for synthetic preservatives and/or colorants. However, the higher production costs and, in some cases, the bitterness of the encapsulates may pose a challenge to wider application of this technology and should therefore be the focus of future studies.