From almond husk sugar to nutritious okara flour: High-value ingredients from food by-products
Renewal Mill is a California-based start-up that upcycles by-products and transforms them into high value and highly nutritional food ingredients. Its first product is okara, the material that is left over from tofu and soy milk production, and is high in fibre, protein, calcium and other nutrients.
It turns okara, which is currently used mainly as an ingredient for animal feed, into a flour that can boost a product's nutritional profile without affecting the taste, texture or appearance, it says, and one of its first customers is German bakery Bahlsen and its R&D wing Hermann’s.
“We don’t think of ourselves as a food waste company. We’re an accessible nutrition company,” Kadakia told us.
At the minute Renewal Mill is working only with okara but its technology can be applied to other by-products too, and it has already begun R&D work into potato peels and pistachio and almond hulls.
Getting to the hull, husk and heart of almonds
Renewal Mill isn’t the only player convinced of the value of almond by-products. The Almond Board of California is exploring the untapped potential of almond hulls, husks and twigs which are currently used as low-value animal feed but could be used to make sugar, beer, nutrient-packed compost for mushrooms, biodegradable plastic and even electricity.
Bill Orts, research lead at the United States Department of Agriculture (USDA) who works on almond co-streams said: “We eat the first third of the almond, which is the kernel, and everything else is a potential co-product. The outer fruit is called the hull and is very rich in sugars, similar to an apricot,” he said.
“You can make a brandy, beer or sugar syrup out of it and add it to tea. It’s eaten in Europe in Spain, so I think it’s a matter of public taste and acceptance.”
According to Guangwei Huang, principal scientist at the Almond Board of California, the process of extracting sugar is “a simple process” that uses very mature technology, similar to extracting sugar from beets.
But is it a sustainable selling point for manufacturers to use these co-streams in their products or should they keep quiet on the origin?
Molly Spence, director for North America at the California Almond Board said: “There is interest in plant-based packaging and if you’re working on a plant-based food and sustainability as part of your brand positioning, it’s very appealing to have that.”
Almonds have a wholesome and natural reputation among consumers, and almond-based plastic packaging could stand to benefit from this, she added.
Kadakia, meanwhile, said it depends on the final consumer. Ethically-minded buyers seeing the co-stream ingredient as an add-on while manufacturers creating products for the mass market may choose not to communicate this.
