At the end of a day making juice, the useful part of a vegetable can look strangely like trash. Claire Schlemme saw that contradiction in Boston, where the organic juice business she co-founded produced a daily mound of fruit and vegetable pulp. She and her team tried the obvious kitchen fixes. They baked some into crackers. They folded some into muffins. The experiments were sensible, even charming, but the pile kept winning. A retail kitchen could make juice much faster than it could invent reasons to eat the leftovers.
That mismatch became more than an annoyance. The pulp still contained nutrition. The farms had already spent soil, water, energy and labor growing it. The customer buying the juice paid for a system that discarded much of what had been grown. Schlemme had started Mother Juice to bring organic produce closer to city customers. Now the operation was showing her another problem, one whose scale was measured every evening in wet fiber.
Most founder stories polish this kind of moment into a flash of revelation. Schlemme’s path was more useful than that. She kept gathering evidence. Food and nature had interested her since college. After graduating from Wellesley in 2006, she worked on organic farms in Spain. She later became an environmental consultant at Industrial Economics in Cambridge, Massachusetts. At Yale, where she completed a Master of Environmental Management in 2011, she learned to examine environmental impact as a system of inputs, outputs and incentives. Mother Juice supplied the mess on the floor.
“We tried to bake it into crackers or muffins, but there was just too much of it.”Claire Schlemme, on Mother Juice’s pulp problem
The second pulp problem
The decisive connection came through Minh Tsai, the founder of Oakland tofu maker Hodo Foods. Soymilk production leaves behind okara, a pale, damp soybean pulp used in some East Asian home cooking but difficult for a large factory to place in sufficient volume. For each pound of soymilk, the process can generate almost a pound of okara. Schlemme recognized the shape of the problem immediately. This was the juice shop’s pulp mountain, translated into industrial units.
She first got okara from a tofu producer near New Haven and began experimenting. The material had attractive qualities for a food ingredient: fiber, protein, a neutral color and a mild taste. It also arrived with an unforgiving condition. Fresh, wet okara can begin spoiling within roughly four hours. Any business built around it would have to move faster than the spoilage clock.
The clever part is not rescuing a byproduct once. It is making the handoff repeatable enough for another production line.
Renewal Mill, founded in 2016, grew around that constraint. Put drying capacity close to where the byproduct is created. Remove moisture quickly. Mill the stable material into a fine flour. Then do the application work required to make it useful in baking and other foods. The underlying environmental idea was broad, but the first business had to be narrow: a specific pulp, a specific process, a specific set of performance characteristics.
This is where Schlemme’s environmental background met the discipline of manufacturing. Waste is easy to condemn in the abstract. A production manager needs specifications. A food scientist needs to know how an ingredient behaves. A buyer needs consistency, safety and a price that makes sense. The rescued material does not get special treatment from a recipe. It still has to work.
A category built from samples
In 2016, “upcycled food” was not yet an easy phrase to put on a sales sheet. Renewal Mill had to sell an ingredient and teach a category at the same time. On the business-to-business side, the company sent samples to research and development teams and helped partners formulate products. On the consumer side, it put its own ingredients into baking mixes and snacks. The two halves supported each other. Ingredient sales could move volume; brownies and cookies could make the concept understandable.
Schlemme’s approach to that uncertainty was deliberately small-scale. She has described the team’s habit of running many little experiments in advertising, influencer work and product development, then increasing spending only when an early test showed a return. It is the sort of operating habit that sounds modest because it is. The company was trying to establish a supply chain, a technical platform and a consumer vocabulary without the budget to pretend every decision was reversible.
The transferable founder lesson
Look for the valuable thing an existing system already pays to discard. Then solve the handoff: timing, consistency, specifications and a buyer with a real use for it.
Packaging offered a blunt lesson. Renewal Mill’s early team made its original visual identity and minimum viable packages in PowerPoint, betting that taste would do most of the work. Taste mattered, but grocery shoppers also made decisions with their eyes. After a professional rebrand launched in 2020, Schlemme said the company added more new retail customers in one quarter than in the previous two quarters combined. Circularity still had to survive the shelf.
Product development brought another important collaborator. Renewal Mill worked with Alice Medrich, the cookbook author and five-time James Beard Award winner known for chocolate and alternative flours, on “just add oil and water” baking mixes. The partnership gave an unfamiliar ingredient a familiar assignment. A shopper did not need to study soybean processing before making brownies. The product could teach through use.
The work behind the clean diagram
A four-box process graphic makes upcycling look inevitable: capture, dry, mill, bake. Schlemme’s account of running Renewal Mill is less tidy. Ingredient sales to large companies can take two or three years. Trade shows and factory visits cost money long before a contract arrives. Consumer products create their own demands: packaging, inventory, logistics, retailer margins and the unforgiving measurement of how quickly a product moves off a shelf.
In 2021, she spoke openly about periods when the company’s bank balance ran frighteningly low. Production remained the expense she would protect. No inventory meant no sales, no samples and no proof that the system worked. She also went without a salary for significant stretches. The candor matters because sustainable manufacturing is often presented through smooth arrows and cheerful labels. The founder still has to pay for the dryer, the bag and the freight.
“Because our budget is so tight, everything we spend on feels important to the success of the business.”Claire Schlemme, on operating Renewal Mill
Caroline Cotto joined Schlemme as co-founder and brought experience spanning food, nutrition, technology and startup acceleration. Together they helped establish the Upcycled Food Association, giving companies in the emerging field common language and, later, a certification shoppers could recognize. Renewal Mill also moved through programs including Food Systems 6, Techstars Farm to Fork and Barilla’s Good Food Makers. Each connection helped the small company reach food manufacturers, investors, retailers and other founders working on adjacent pieces of the system.
From one ingredient to a map
Okara was a starting point, not an identity Schlemme wanted the company trapped inside. The same general challenge appears wherever food is pressed, brewed or strained. Oatmilk leaves oat pulp. Juicing leaves fruit fiber. Other plant-milk processes leave pea and almond material. Oil pressing, winemaking and potato processing all create streams that may contain useful food value but lack a convenient next customer.
Renewal Mill’s expansion has followed that map. It has worked with oat pulp and tested other plant byproducts, while offering formulation support to brands. The goal is a portfolio of ingredients rather than a single novelty flour. That shift changes the company’s role. It becomes less a seller of one rescued material and more a translator between manufacturers with a disposal problem and product developers looking for performance, fiber or protein.
The company reports that it has kept more than one million pounds of nutrition in the human food system. The number is meaningful because it counts what the process is designed to preserve, but it also points back to the mundane unit of progress: one production partner, one stabilized batch, one formulation that passes a sensory test, one product that gets ordered again.
In 2025, Renewal Mill was selected as one of 20 finalists in the Grow-NY food and agriculture competition and pitched at the November summit in Canandaigua. The location carried a personal connection. Schlemme had spent summers with her grandparents on Canandaigua Lake, and she wrote publicly about the Finger Lakes as a place of farms, producers and community that had long felt like a second home. The company did not take one of the seven cash awards, but the finalist run placed its next chapter in a region built around food production.
The practical optimism of leftovers
Schlemme’s career keeps returning to the same move: look again at what a system has classified as excess. The organic farms in Spain, environmental consulting, Yale, a farmers-market juice table, a tofu factory and an ingredient mill are not separate episodes so much as increasingly detailed views of resource use. Each one made the cost of a missing connection more visible.
Her work also resists the idea that responsibility belongs only to the shopper standing over a compost bin. A great deal of food loss happens before a product reaches a kitchen. Manufacturing creates clean, concentrated byproducts in predictable places. That makes the problem industrial, but it also makes it addressable. The stream can be measured. Equipment can be placed beside it. A specification can be written. A sales team can find the next use.
The aspiration is a waste-free food system that keeps affordable nutrition in circulation. The method is less sweeping: start with the wet pulp in front of you, learn its clock, and give it a job someone will pay it to do. For Schlemme, the business hiding in the pile was never merely flour. It was the possibility that a supply chain could learn to notice more of what it already had.