Influence of maize hybrid on bioethanol yield and quality of dried distillers' grains

Abstract

Maize (Zea mays L.) is one of the most important cereal crops. and one of the most significant renewable raw materials for the production of energy and many different products. Bioethanol is a biofuel that is mostly used as a replacement for fossil fuels worldwide. Major by­product that arises from the fermentation process of corn is dried distillers' grains (DDG). Due to its high feeding value it represents an excellent component for livestock feed mixtures. The main goal of this study was to determine the technological quality of maize grain and the influence of maize hybrid on bioethanol yield and quality of this process' by-product, dried distillers' grains. Five maize hybrids developed at the Maize Research Institute, Zemun Polje, were investigated in this study. The lowest concentration of bioethanol in the fermentation medium after 44h of alcoholic fermentation (8.64% w/w) was obtained by hybrid ZP 560, and the highest (9.10% w/w) by hybrid ZP 600, while compared to the maximum theoretical bioethanol yield, the highest scoring hybrid was ZP 606 (93.59%) and the lowest ZP 505 (87.33%). The highest in vitro dry matter digestibility of DDG was determined in a sample obtained from hybrid ZP 505 (82.41%) and the lowest (77.12%) in the DDG sample of ZP 606. The chemical composition and physical characteristics of the grain, as well as other parameters of the production process have influenced the overall bioethanol yield. Hybrids created in the Maize Research Institute represent unique starting material for research of the possibilities of bioethanol, starch, food and animal feed production.

Kukuruz (Zea mays L.) je jedna od najznačajnijih ratarskih biljaka koja se svrstava u veoma važne obnovljive ugljenohidratne sirovone za proizvodnju energije i mnogobrojnih proizvoda različite namene. Bioetanol je biogorivo koje se najviše koristi kao zamena za fosilna goriva. Trend proizvodnje ovog goriva je rastući, a kukuruz zahvaljujući visokom sadržaju skroba u zrnu, predstavlja jednu od najboljih obnovljivih sirovina za njegovu proizvodnju. Suva kukuruzna džibra je najznačajniji sporedni proizvod dobijanja bioetanola iz kukuruza. Zahvaljujući visokoj hranljivoj vrednosti, sadržaju proteina i drugih hranljivih materija, predstavlja kvalitetno hranivo koje može naći primenu kao komponenta u smešama za ishranu životinja. U cilju ispitivanja uticaja hibrida kukuruza na kvalitet zrna, fermentaciona svojstva, prinos bioetanola i kvalitet suve kukuruzne džibre korišćeno je zrno pet hibrida kukuruza stvorenih u Institutu za kukuruz 'Zemun Polje'. Najnižu koncentraciju bioetanola u fermentacionom medijumu nakon 44h alkoholnog vrenja (8,64 % w/w) ostvario je hibrid ZP 560 a najvišu ZP 600 (9,10 % w/w). U odnosu na maksimalni teorijski prinos najviši je imao hibrid ZP 606 (93,59%), a najniži ZP 505 (87,33%). Najveća in vitro svarljivost suve materije kukuruzne džibre određena je u uzorku dobijenom od hibrida ZP 505 (82,41%), a najniža (77,12%) u uzorku džibre hibrida ZP 606. Hemijski sastav i fizičke karakteristike zrna, kao i drugi parametri procesa proizvodnje uticali su na prinos bioetanola.