Coffee Beans inherently emits carbon dioxide after roasting. Carbon dioxide is actually not bad and can actually preserve the roasted beans. Roasted coffee beans degrades when comes in contact with oxygen in air. Hence, it is best to keep it in air tight http://premier-pharmacy.com/product-category/skin-care/ container to prevent air to come in contact with the beans.
Keep it away from light and store in in dark places. Storing it in cool place can help to preserve the roasted bean but do not store them in refrigerator.