Comparison of Compositions of Imported Genetically Modified and Organic Soybeans Purchased from Taiwan Market

Abstract

Soybean is an excellent source of plant-derived protein, and soy products are one of the important protein sources for vegetarians in Taiwan. Soybean production in Taiwan is not self-sufficient. Taiwan imports 2.5 million tons of soybeans annually. More than 90% of the imported soybeans are genetically modified. To provide an objective assessment on safety of genetically modified soybean and for post-market monitoring, we conducted a comparative assessment on key component compositions between imported genetically modified and organic soybeans. All the soybean samples were purchased from the local market to simulate the status of Taiwanese consumers purchasing soybeans. The genetically modified soybean samples were herbicide-tolerant soybeans. The contents of the proximate, the amino acid composition, the fatty acid composition, vitamins, minerals, isoflavones, and anti-nutritional factors of soybean samples were analyzed. Most contents of the key components of the genetically modified soybean had no significant difference with those of the organic soybean in this study. However, the contents of cysteine and α-linoleic acid were significantly lower in the genetically modified soybean samples, and the contents of crude fat, palmitic acid, stearic acid, oleic acid, linoleic acid, vitamin K1, and calcium were significantly higher in the genetically modified soybean samples. But they were all within the range of reference values. A total of 314 pesticide residues in each of the samples were analyzed. Only glyphosate residue was detected in the genetically modified soybean samples, but it is well below the threshold prescribed by the government. In summary, the imported genetically modified and organic soybeans purchased from Taiwan market were shown to be substantially equivalent in composition.