We did an experiment to examine the viability of different seeds using biochemical methods, basing on the principle that the dehydrogenase can reduce tetrazolium to formazans, a red, insoluble substance. One group of seeds were pre-heated at 100°C for at least 30 minutes and we found that most of the pre-heated mung beans turned red. Does that mean that the seed was still alive? But how could it maintain viability after boiling?