CPIB, Multidisciplinary Centre for Integrative Biology, School of Biosciences, the Univ. of Nottingham, Sutton Bonington Campus, LE12 5RD, UK.
J Food Sci. 2010 Sep;75(7):R131-8. doi: 10.1111/j.1750-3841.2010.01733.x. Epub 2010 Aug 23.
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 3 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-null 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.
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. 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.
在加工食品工业中，大豆匀浆中通过脂氧合酶（LOX）途径产生的异味，如正己醛，可能是一个问题。先前的研究已经研究了使用缺失一种或多种 3 种 LOX 同工酶的大豆品种对正己醛生成的影响。使用从现有数据估计的参数，使用常微分方程构建了大豆 LOX 途径的动态数学模型，目的是预测如何减少正己醛的生成。对 LOX 缺失的豆类进行了时程模拟，并与实验结果进行了比较。与实验中发现的野生型相比，模型 L(2)、L(3)和 L(12)豆类在相对范围内，而 L(13)和 L(23)豆类接近实验范围。与实验相比，模型 L(1)豆类产生的正己醛相对较多。敏感性分析表明，降低 LOX 同工酶 3（L-3）的估计 K(m)参数将改善模型预测与文献中实验结果之间的拟合度。该模型还预测，增加豆类中的 L-3 或减少 L-2 水平可能会减少正己醛的生成。
这项工作描述了使用数学来尝试量化大豆匀浆中化合物在酶催化作用下转化为不良风味的情况，主要是从化合物正己醛开始。还研究了不同大豆基因型和酶动力学常数的影响，提出了哪些组合可能最大限度地降低异味水平的建议，以及可能进行哪些进一步的工作来证实这些结论。
