Dr. Josette Lewis
Dr. Josette Lewis is the Chief Scientific Officer of the Almond Board of California and has worked in agriculture for more than 25 years, spanning government, industry, university and non-governmental organizations. She oversees ABC’s grower-funded research on growing almonds, innovative uses of co-products and almonds’ health benefits.
For California’s almond industry, innovation doesn’t stop with the kernel. The Almond Board of California continues to both add value to the food industry and fight climate change. Their latest advance will help upcycle almond hulls into food for people.
The almond industry has worked for years to make the most use of everything that grows in their orchards, working hard toward a key goal of achieving zero waste in their orchards by 2025.
In the latest developments, the Almond Board of California (ABC) and the food scientists at Mattson in the San Francisco Bay Area reached the crucial step to demonstrate that almond hulls —the soft fruit-like covering that grows around the shell— can be used as a value-added ingredient in food, including high-fiber nutrition bars, coffee, tea and, possibly, even beer, though the beer is still a work in progress.
ABC has been collaborating with Mattson for more than a year to upcycle almond hulls to enrich a range of food. Mattson has taken advantage of the positive flavor and the health attributes of hulls by using powdered hulls as a food ingredient.
Mattson’s prototypes demonstrate not only pleasant taste in products such as nutrition or snack bars, but also health benefits by elevating the fiber content and reducing the carbohydrate value. With fewer than 10% of Americans consuming the recommended daily level of fiber, upcycling almond hull adds needed nutritional value without compromising taste.
For food companies, upcycling hulls also leverages the sustainability of California almonds. Almonds’ zero-waste story is impressive, and it is backed by a range of published peer-reviewed research. It starts with this: With the same resources that produce an almond, growers actually produce four crops: the kernel, the shell, the tree and the hull.
Hulls and shells are used by the dairy industry. For every pound of almonds California farmers produce, they produce more than 1.5 pounds of hulls. In 2022, almond hulls displaced the need for nearly 400,000 acres of alfalfa, saving 1 million-plus acre feet of water, enough for more than 2 million households a year, and avoiding the equivalent of 2.861 tons of CO2.
In a world facing climate change, the trees alone have enormous value. An acre of California almond trees captures and stores 1.18 metric tons of CO2 annually, 40% more than the annual carbon storage of an acre of US forest. When you look at all the carbon captured by almond trees in California in 2022, it was the equivalent of taking 6.6 million cars off the road.
At the end of the life of an orchard, all that carbon captured in the trees can be added back to the soil at the end of the orchard’s life by grinding the trees into mulch and plowing them back into the ground in what is called whole-orchard recycling.
Whole-orchard recycling was pioneered by the California almond industry and the benefits are many. Already adopted in an estimated 50% of California almond orchards, recycling increases the soil’s organic matter by 42%, water-holding capacity by 32% and increases cumulative yield over five years in the new orchard by 19%. It’s a win for the climate and for the farmer.
Beyond whole-orchard recycling, companies are using almond wood and shells to replace plastics or strengthen recycled plastics in industrial applications. One start-up company is looking at almond wood as a feedstock for sustainable fabric production.
With California regulations requiring both a greening of the energy grid and low-carbon fuel for transportation, more companies are testing almond wood and shells for biofuels. Two life-cycle assessments of California almonds demonstrate that these co-product uses will lower, maybe even neutralize, the carbon footprint of almonds, already one of the very lowest-carbon foods.
And then there are the hulls. Hulls are the untold piece of the almond story, even beyond their use in dairy that reduces alfalfa needs and so dramatically decreases water demand.
It helps to know that almonds are not technically nuts. They’re drupes, like peaches. The almond shell is akin to the peach pit and the kernel is inside that pit/shell. The almond hull is like the peach flesh. If hulls take off as a food ingredient, the more appropriate label may be “almond fruit.”
The Mattson proof-of-concept samples definitively show that these sustainable, nutrient-rich, zero-waste ingredients are viable additions to future healthy food products —and can offset the need to grow or produce other ingredients.
In parallel to Mattson’s product innovation, the Almond Board of California is funding the food safety assessment of almond hulls and expects to submit a dossier to the U.S. Food and Drug Administration to be Generally Recognized as Safe in early 2024.
The California almond industry works hard to grow one of the healthiest foods on the planet as responsibly as possible and to be both great stewards of their lands and good partners to all the industries, companies and people they deal with. Upcycling the nutrition and value of almond hulls is one of the many steps on that road.
All images courtesy of the Almond Board of California.
Almond hull tea with almond hull nutrition bars
Almond hull beer with almond hulls