The color of bovine rumen can vary from green to light beige. This difference arises because cows do not always receive the same ration. When cows graze in the pasture and eat mainly fresh grass, the rumen is greener in color. If cows are kept in the barn and are fed silage and dry feed, among other things, the rumen is lighter in color.

Both variants are nutritionally high-quality. Because the rumen is rinsed but not completely cleaned, small remnants of rumen contents remain. As a result, bovine rumen naturally contains digestive enzymes and beneficial bacteria, such as Lactobacillus acidophilus (lactic acid bacteria), an important component of probiotics.