IN ITS quality laboratory kitchen in Indooroopilly, Queensland, the CSIRO soybean team adds a coagulant — with an effect something like that of a junket tablet — to milk extracted from a wide range of established and experimental soybean lines from the breeding program.
The tofu-making process then proceeds through cooking — at around 98°C — and refrigeration until evaluation, which is visual after each container is emptied and the contents subjected to a 'cleave test'.
The best tofu lines cut cleanly, with the moulded tofu retaining its shape. Colour is important, says program leader Andrew James. "Tofu should be as white as it is possible to get.
"We've identified varietal differences in yield of soy milk, with a consistent response to genotype, and the beans with the highest oil content also tend to produce more milk.
"Tofu quality depends on how well the soy milk gels, and as the beans get older — further away from harvest — the tofu-making quality declines.
"While we're still learning about making quality tofu, we have had Japanese visitors here who have told us what we are doing should eventually deliver the right answers. "