As a vegan, I intend to use tofu as my main source of protein, iron and calcium. Therefore, I am concerned about bioavailability (i.e. absorption divided by intake) of iron and calcium in tofu.
As far as I know, there're two kinds of tofu, divided by a difference in their production process:
- Those treated with CaSO4, known in US/UK as "calcium-set tofu", and in China as "southern tofu".
- Those treated with MgCl2 (among other substances), known in US/UK as "traditional tofu" (not sure), and in China as "northern tofu".
These two kinds vary greatly in calcium content: roughly 300+mg/100g for the former, and 100+mg/100g for the latter. [1]
There had been studies on the iron bioavailability in tofu ([2]).
There had also been studies on the calcium bioavailabity in calcium-set tofu ([3],[4]), which give us some good news (that calcium-set tofu is not even defeated by milk).
However, I hadn't found any infomation on the calcium bioavailabity in traditional tofu. So, could you share your relevant experiences, or point out some relevant studies?
UPD: Luckily I've found ways to get around this problem, so answer to this question doesn't matter much to me now.
I'll post links to another paper that I found quite useful, in case it can help somebody: [5], [6]
The paper is about mineral content in all kinds of common soy products in China, and it's written in Chinese.
