A: Most dried, baked, roasted food products, jams and jellies do not need to be tested by you or a commercial lab. If you make up your own recipe and add low-acid or high-moisture foods, then you should have the product commercially tested. Water activity meters are expensive, around $2,000. It is less expensive to have the product tested by a lab.
This blog answers questions related to making and selling safe food under the Minnesota cottage food law.