We’ve been hearing from more people interested in selling prepared foods at markets. The University of Maine Cooperative Extension has a helpful bulletin, Recipe to Market: How to Start a Specialty Food Business in Maine, with details about what is required for various types of foods, and links to excellent resources (including commercial kitchens that can be rented for production). The Department of Agriculture, Conservation, and Forestry (DACF) has a detailed reference guide about what is required for various types of food.
Fall is an excellent time to start planning to add prepared foods to your market repertoire for next year, as it does take time, starting with getting a kitchen licensed. Many simple baked goods and relatively low-risk foods (such as pickles and jellies) can be safely prepared in a certified home kitchen. (The DACF food safety inspectors will work with food producers to ensure a smooth licensing process.) Commercial kitchens are required for foods like sandwiches, soups, and pasta salads. Though such a facility may be hard to add to the typical home, there are commercial kitchens that can be rented for periods of hours, and it is also possible to arrange for someone else to prepare your products in their commercial kitchen (see the document linked above for more information).
Developing new products also involves product review (safety) testing, a process which can take 6 weeks or more. Although they must be produced in a licensed kitchen, most baked goods, fruit-based jams/jellies, and candies/confections do not need to be sent to UMaine for food testing. Foods like dessert sauces, pickles, and salsa will need to be tested (details are available online), which requires sending samples to the University of Maine. (People using well water will need to have their water tested regularly as well.) Product testing is fairly costly, but once approved, a recipe can be used year after year. Many producers add a couple of new products (or new sizes of existing products) each season, making the process more affordable.