The color of beef rumen can vary from green to a somewhat lighter/beige color. This is because cows do not always have the same diet. When cows are in the meadow, they eat fresh grass all day long, which gives the rumen a green color. When the cows are inside the barn, they are fed with grass silage and dry food, among other things. This makes the rumen somewhat lighter in color. In terms of nutritional value, both 'types' are high-quality, because they are rinsed, residual rumen contents remain present. The rumen therefore contains natural digestive enzymes (including Lactobacillus acidophilus: lactic acid bacteria, which is the main component of probiotics).
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