Medium quality ingredient - nutritionally adequate and unlikely to cause any problems
Barley in dog food
Barley is commonly used in dog food in a variety of forms. Once cooked it is easily digested by dogs and provides abundant fibre and several micronutrients including selenium and copper. Whole grain barley is the best form as it retains most of its nutrients.
In humans, barley gluten has been indicated as a problem ingredient for celiacs so if you are looking for a gluten free food, it would probably be best to steer clear of barley as well as wheat.