Grape seeds are rich in powerful antioxidants and natural plant compounds called oligomeric proanthocyanidin complexes (OPCs). OPCs are most well-known for their antioxidant activity, which means, grape seeds may help to destroy free radicals in your body, which in turn may help you avoid premature aging and certain chronic diseases. The seeds are ground into a fine powder that is roughly the same texture as wheat flour. Since this flour is gluten free, grape seed flour will often creates a slightly denser product if used in large quantities. It will add a bit of a whole grain texture to  bread or baked good, as well as quite a bit of color. There is no daily recommended amount at this time, but some studies used doses of 3 grams/day.