The phrase "rice yeast" refers to a type of yeast that is made from rice and is commonly used in cooking and fermentation processes, like making sake or rice wine. Full definition
(2) Ener - G Foods Brown Rice Yeast Free Loaf, (3) Julian Bakery (website) has a paleo bread made with almond flour. (glutenfreewatchdog.org)
Tried to push me on red rice yeast and I said no thank you. (freetheanimal.com)
A species isolated from red Koji or Honqu (as red rice yeast is known in East Asia) was named Monascus Purpureus Went in 1895, in recognition of the purple coloration. (bio-alternatives.net)