Phytate degradation in a mixture of ground wheat and ground defatted soybeans during feed processing: effects of temperature, moisture level, and retention time in small- and medium-scale incubation systems.
The optimal conditions for degradation of phytate (IP6, myo-inositol hexaphosphate) in a mixture of ground wheat and ground defatted soybeans (1:2, w/w) with added exogenous E. coli phytase were investigated at different temperatures (45, 60, 75, and 95 degrees C), moisture levels (25%, 35%, and 45%), and retention times (2-45 min). All treatment combinations were investigated in a small-scale mixer conditioner (experiment 1). The combined 45 degrees C and 45% moisture treatment was most efficient and reduced the content of IP6 by 86% during 45 min of incubation. This treatment combination was applied in a medium-scale mixer conditioner (experiment 2), and 76% reduction of IP6 at 45 min was obtained. During incubation, the content of lower groups of inositol phosphates, such as IP4 (myo-inositol tetraphosphate) and IP3 (myo-inositol triphosphate), increased significantly as the content of IP6 decreased. The major isomer formed was Ins(1,2,5,6)P(4).
Denstadli
Vegard
V
Aquaculture Protein Centre, CoE, Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, As, Norway.
Vestre
Rotsukhon
R
Svihus
Birger
B
Skrede
Anders
A
Storebakken
Trond
T
D010832:6-Phytase / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology; D005511:Food Handling / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D010833:Phytic Acid / Q000378:metabolism*; D013025:Glycine max / Q000737:chemistry*; D013696:Temperature; D013997:Time Factors; D014908:Triticum / Q000737:chemistry*; D014867:Water / Q000032:analysis
D014867:Water; D010833:Phytic Acid; D010832:6-Phytase