Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Tainted Product?

I've been using Pamela's products with great success, ordering a case of the bread mix from the Amazon onlinePamela's Products Wheat-Free & Gluten-Free Bread Mix, 19-Ounce Packages (Pack of 6)grocery every month. But in November, the bread started to have a very strange chemical after taste and also gave both my husband and myself serious digestive upset. I made a few more loaves to see if it was just one bag of the mix, but no, it seems to be a recurring problem. We also purchased a bag of Pamela's GF white cake mix from the grocery store recently and it had the same noxious taste and smell. What's up? I have three cases of the bread mix that I plan to return to Amazon for a refund.