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"The truth is: China does not grow genetically modified potatoes, and there is no country in the world that approves the commercial planting of potatoes with the trans-polyphenol oxidase gene. Whether potatoes turn black (browning) after shredding or peeling has a lot to do with the variety as well as the environmental conditions. The speed and degree of blackening is mainly determined by the content of phenolic substances, polyphenol oxidase activity, and whether or not after low-temperature refrigeration and so on."