Avoiding Soybean Off-flavors

October 27/Loughborough, U.K./Journal of Technology & Science -- According to recent research published in the Journal of Food Science, "The generation of off-flavors in soybean homogenates such as n-hexanal via the lipoxygenase (LOX) pathway can be a problem in the processed food industry. Previous studies have examined the effect of using soybean varieties missing one or more of the three LOX isozymes on n-hexanal generation."

"A dynamic mathematical model of the soybean LOX pathway using ordinary differential equations was constructed using parameters estimated from existing data with the aim of predicting how n-hexanal generation could be reduced. Time-course simulations of LOX- beans were run and compared with experimental results. Model L-2, L-3, and L-12 beans were within the range relative to the wild type found experimentally, with L-13 and L-23 beans close to the experimental range. Model L-1 beans produced much more n-hexanal relative to the wild type than those in experiments. Sensitivity analysis indicates that reducing the estimated K-m parameter for LOX isozyme 3 (L-3) would improve the fit between model predictions and experimental results found in the literature. The model also predicts that increasing L-3 or reducing L-2 levels within beans may reduce n-hexanal generation. Practical Application: This work describes the use of mathematics to attempt to quantify the enzyme-catalyzed conversions of compounds in soybean homogenates into undesirable flavors, primarily from the compound n-hexanal," wrote N. Mellor and colleagues, University of Nottingham.

The researchers concluded, "The effect of different soybean genotypes and enzyme kinetic constants was also studied, leading to recommendations on which combinations might minimize off-flavor levels and what further work might be carried out to substantiate these conclusions."

Mellor and colleagues published their study in the Journal of Food Science ("Reduction of Off-Flavor Generation in Soybean Homogenates: A Mathematical Model." Journal of Food Science, 2010;75(7):R131-R138).

For additional information, contact C. Hodgman, University of Nottingham, CPIB Multidisciplinary Center Integrat Biology, School Bioscience, Sutton Bonington Campus, Loughborough LE12 5RD, Leics, United Kingdom.

From the November 15, 2010, Prepared Foods E-dition