ONETANG brand shiitake mushroom series add no preservatives, process without sulfur fumigation, best-selling in European and American markets more than ten years, safe and delicious, is your best choice for health. Our factory and mushroom have passed multiple international tests, certificated by BRC, HACCP, and ISO22000, also accessed to FDA green channel. In order to secure the quality, we strictly control every aspect from cultivation to the finished product.