When Hannah Barnstable started selling her homemade muesli at Minneapolis farmers markets seven years ago, she knew she wanted her cereals to be a force for good.

Now, with national distribution and on the cusp of even greater expansion, Seven Sundays — the company she and her husband, Brady Barnstable, founded — is the first Minnesota food maker to become a certified B corporation. Like other designations, such as organic or fair trade, B corporations must meet clear standards.

B corporations span a variety of industries and are meant to act as a structure to help for-profit entities balance social and environmental responsibility. It is also a way to quickly signal values to consumers who might buy something based on a product's effect on people and the planet.

"We weren't changing our model to become B corp, but we got to the size that we felt it would benefit our conversations with retailers and consumers," Hannah Barnstable said. "When you expand outside your core customer base to places where not everyone knows you, the certifications are really important."

And while Seven Sundays is the first Minnesota food company to achieve B corporation status, two Minnesota-based beverage companies — Peace Coffee and Superior Switchel — are also certified B corporations. B corporations are different from public benefit corporations, but both are meant to signify a social enterprise. B corporations must meet transparency standards for maintaining certification while a public benefit corporation is a type of legal incorporation that varies state-to-state.

The Barnstables started creating their own muesli after eating it daily on their honeymoon in New Zealand. Muesli is a cold breakfast cereal that is a combination of oats, grains, dried fruits and nuts that are soaked in milk or other liquid overnight. It was first created in Switzerland around the turn of the 20th century and spread throughout Europe — and European colonies. Minneapolis-based Seven Sundays is sold in about 4,500 stores nationwide, including Sprouts, Kroger, Safeway and select Costco club stores. As the company prepares for its launch in Whole Foods stores nationwide in January, the couple decided it was time for Seven Sundays to formalize their philosophy.

"We aren't just selling in Minnesota anymore. We are nationwide and we want to make sure people know what we stand for," Hannah Barnstable said. "Secondly, as a still privately held, family-run business, we want to make sure there is a legal framework in place for something to stand behind as we grow and it's no longer just Brady and I making all the decisions."

Unlike some food-certification programs that are "about checking the boxes and then moving on," Barnstable said in order to maintain the B corporation certification, a company must show continual improvement across five categories: community, workers, consumers, environment and governance.

It took Seven Sundays many months to submit all of its legal and policy paperwork to B Labs, the certifying organization. The certification "literally touches every part of the business," Barnstable said.

In order to even start the process, Seven Sundays had to take an impact assessment to make sure it received the pass score of at least 80 on a 200-point scale. Most companies fall between 40 and 100. The company currently has a score of 84.3 and must disclose its progress on the B corporation directory. If Seven Sundays fails to improve that score in three years, it will lose the certification.

She said it was arduous to gain B corporation status, but that it will help the firm better introduce itself to a more national audience.

B corporations are also supposed to have a purpose higher than simply making money — and it has to be more than just a catchy motto that sounds altruistic.

According to its B corporation report card, Seven Sundays' mission is to maximize nutritional value (read: no added sugar) while minimizing the environmental effect of the foods it makes. For them, that comes down to sourcing plant-based, non-GMO, gluten-free and nutrient-dense ingredients near their St. Peter, Minn., and Connecticut production facilities. As a secondary purpose, the company aims to support family farms in the Midwest by creating demand for small grains grown in the region.

Minnesota has 18 certified B corporations, ranging from data and analytics companies to marketing and communications firms.

There are far more public benefit corporations in Minnesota, according to the secretary of state's website, which lists 86 companies, including several in the food and beverage space.

Seven Sundays already has plans in the works to improve its score. By the first quarter of 2020, all of its soft-shell cereal packages will be made from post-consumer recycled materials. B Labs pressed the company to be responsive to its consumers. Packaging was one of Seven Sundays customers' top concerns. And while Barnstable wants to eventually move to an entirely compostable package, the market has work to do in order to make that more feasible in packaged foods, she said.

"If you put the cereal in a compostable package, you have to put a shorter shelf life on the products, and you have to monitor the shelf life more and that gets into inventory issues," Hannah Barnstable said. "I'm not sure if the consumer market is quite there. We know we want to be a part of the solution. Post-consumer recycled material is the most immediate impact. I call it a baby step."