Why does soy milk sometimes curdle in my coffee and sometimes not?

Answer by  malone (4817)

It is likely due to the temperature difference between the hot coffee and the cold soy milk. Try this: put the soy in the cup first then add just a bit of coffee to "temper" the milk. Give it a swirl to mix, then fill your cup.

Answer by  GeekBoy (146)

I can't say for sure. The soy milk itself may be spoiled, causing it to curdle. If the soy milk is fresh, the coffee may contain a flavoring that doesn't mix well with soy milk. Some citrus-enhanced teas cannot be mixed with milk or they'll curdle.

Answer by  debichance (160)

It could be that the soy milk is spoiled. It may also be the temperature of the coffee that is causing the soy milk to curdle. If the coffee is too hot, adding cold soy milk could cause the soy milk to curdle.

Answer by  Anonymous

it probably has more to do with the acidity of the coffee and the difference in temperature between hot coffee and cold milk.

Answer by  elaine (450)

It's a supernatural effect: the coffee is trying to warn you that by adding toxic soy to the cup you are in danger. Soy can only be consumed by humans in its fermented form (miso, etc.) and should never be ingested if you are interested in staying healthy which I guess is why you are using it. An error.

Answer by  Anonymous

WEll firstly i want to ask you what you mean by the soy milk curdling because such as phenomenon is highly unlikely and very improbably. Alas, can I suggest that you use the milk from the good cow to consume your coffee, if thats okay?

Answer by  heather88 (1897)

It sometimes does that because the soy milk is very moody, and doesn't like the coffee that day. It possible just had an off day. It maybe because it was just bad that day, or something about the coffee made it curdle.