The nutritional value of micronised grain of cereals and legumes

Abstract

Micronisation is a contemporary, ecologically safe technology whose role in the food and feed industry has been increasing. This technological process is based on the impacts of a temperature developing due to the emission of infrared rays of 1.8 to 3.4 microns in length. Mercantile grain of cereals, wheat, barely and maize, as well as, of legumes, soybean and field pea, was exposed to infrared rays at the temperature of 145oC. The basic chemical composition (ash, crude fibre, starch, total protein and oil), as well as, the content of soluble proteins, trypsin inhibitors, urease, resistant starch and dry matter digestibility were analyzed in fresh grain and flakes produced after the micrionisation treatment. The changes of the basic chemical content in flakes of cereals and legumes cannot be attributed to the effect of high temperatures in the course of micronisation. High temperatures resulted in the decrease the content of water soluble proteins in grain of cereals and legumes, as well as, in the reduction of the content and the activity of observed antinutritional substances. The digestibility of legume grain under the effects of high temperatures was reduced by approximately 3%, while the digestibility of maize and wheat grain was increased. It can be concluded that high temperatures in the course of micronisation did not affect enzymatic hydrolysis of cereal starch, but a significant effect on the reduction of resistant starch was observed in field pea.

Mikronizacija spada u savremene, ekološki bezbedne tehnološke postupke, koji se sve više koriste u prehrambenoj industriji i industriji stočne hrane. Ovaj tehnološki proces se zasniva na dejstvu temperature koja se razvija usled emisije infracrvenih zraka talasne dužine od 1,8 do 3,4 mikrona. Merkantilno zrno žita, pšenice, ječma i kukuruza, kao i zrno leguminoznih biljaka, soje i stočnog graška podvrgnuto je dejstvu infracrvenih zraka na temperaturi od 145oC. U sirovom zrnu i pahuljicama dobijenim nakon tretmana mikronizacije analiziran je osnovni hemijski sastav (pepeo, celuloza, skrob, ukupni proteini i ulje), kao i sadržaj rastvorljivih proteina, tripsin inhibitora, ureaze, rezistentnog skroba i svarljivost suve materije. Promene osnovnog hemijskog sastava u pahuljicama žita i leguminoza ne mogu se pripisati uticaju povišene temperature tokom procesa mikronizacije. Povišena temperatura uticala je na smanjenje sadržaja u vodi rastvorljivih proteina u zrnu i žita i leguminoza, kao i na smanjenje sadržaja i aktivnosti ispitivanih antihranljivih materija. Svarljivosti zrna leguminoza pod uticajem povišene temperature smanjena je za oko 3%, dok je svarljivost zrna kukuruzna i pšenice povećana. Može se zaključiti da povišena temperatura tokom mikronizacije nije uticala na enzimsku hidrolizu skroba žita, ali zapažen je značajan uticaj na smanjenje sadržaja rezistentnog skroba kod stočnog graška.