My family and I have been in the Tofu and Soy Milk business for over 40 years. We have used this brand of Calcium Sulfate from the very beginning to make our Chinese Pressed Tofu. As a large Tofu manufacturing company, we need to ensure that our finished products are free of any black specks or impurities. This is why we use this brand, simply because it has remained clean and reliable. So reliable that we can recommend it to our customers that want to try tofu making for themselves. Also, it is 100% Product of USA so the production methods are held to a higher standard.