I know Sensient Flavors has a number of yeast cell wall and beta-glucan products. (5600 West Raymond Street, Indianapolis, IN 46241-4343, United States). I know one of their reps - want me to see if he will send a free sample?
Paul, Pete Cheplick from Sensient got back to me yesterday and said he would be glad to talk to you. His email is [email protected]. Apparently they have a strong European animal business so think they can get you some yeast cell wall materials.