I've actually found that it doesn't usually make a noticeable difference for soy yogurt whether I heat the yogurt to 45 °C or some lower temperature or even at

I've actually found that it doesn't usually make a noticeable difference for soy yogurt whether I heat the yogurt to 45 °C or some lower temperature or even at all, at least when using a electric yogurt maker (or other device with active heating). Maybe I need to try them side-by-side because I assume there's some reason many people suggest heating the milk first. I just mix the existing soy yogurt with soy milk, both of which only consist of soybeans, water, and cultures which seems to be the most reliable option. It involves virtually no effort this way.