I can make a nice microfoam with both brands of soy milk I use (Earth Balance unsweetened and Organic Valley unsweetened) but when I pour to make latte art, it is too thick and floats, creating poorly defined shapes at best.
I heard about a Pacific brand soy milk made specifically for making lattes called Barista Series, Soy Blenders. I looked it up on amazon.com and start reading people’s comments. People seemed to really like it and pointed out that it was able to withstand higher temperatures than other soy milk. I found the information and photo below on the pacific foods web site and they too claim that it can withstand high temperatures.
Pacific Barista Series™ Original Soy Beverage (Formerly Plain Soy Blenders)
Specially formulated to withstand high temperatures and deliver consistently smooth, velvety microfoam. It performs as well as (or even better than) dairy – perfect for latte art.
I did further research on the subject of soy milk curdling at high temperatures. There was a a difference of opinion on the cause. Some said that it was due to excessive heat while others claimed that it was caused by acidity.