Original scientific paper
THE EFFECT OF THERMIC TREATMENT CONDITIONS ON THE AMINO ACID COMPOSITION OF SOYBEAN AND MAIZE
Éva Varga-Visi
; University of Kaposvár, Faculty of Animal Sciences, Kaposvár
Gabriella Pohn
; University of Kaposvár, Faculty of Animal Sciences, Kaposvár
Csilla Albert
; Sapientia Hungarian University of Transylvania, Csíkszereda Campus, Hungaria
Zsolt Mándoki
; University of Kaposvár, Faculty of Animal Sciences, Kaposvár
János Csapó
; University of Kaposvár, Faculty of Animal Sciences, Kaposvár
Abstract
Protein is one of the most valuable components of fodder, therefore there is a concern preserving over these components in an available form during different treatments wherein heating is applied. The aim of the research was to investigate the influence of toasting of fullfat soybean and air-drying of maize on the amino acid profile of the products. Dried maize was sampled at two Hungarian drying plants. The maize was dried with an industrial Bábolna B1-15 type gravitational drying tower. The influence of toasting on two sorts of fullfat soybean products (hydrothermic soy coarse and ‘natural’ hydrothermic soy) was investigated. Soybeans were heat processed with an industrial KAHL HR-1600 type hydrothermic reactor after cracking. The amino acid analysis of samples was carried out with amino acid analyzer and amino acid enantiomers were quantified with a LaChrom type MERCK-Hitachi high performance liquid chromatograph. The D-amino acid content of the samples before and after drying did not differ significantly, not even at the applied highest temperatures (100 ºC drying air temperature and 40-45 ºC kernel temperature). Pressurized steam cooking of fullfat soy did not result in a significant increase of the amount of D-enantiomers or a decrease of the concentration of L-amino acids (P>0.05), while the trypsin inhibitor activity (TIA) was reduced to the required level (TIA<1.5 mg/g) and the results of the urease test (ΔpH<0.2) also verified the adequate intensity of the heat treatment.
Keywords
thermic treatment; soybean, maize; toasting; air-drying; amino acids
Hrčak ID:
50649
URI
Publication date:
25.9.2009.
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