The Almond Board of California, in collaboration with Mattson, a food science company in the Bay Area, has devised a plan to reduce waste in the almond growing process — upcycling.
The idea is to repurpose the almond's outer hull, a fleshy fruit which falls in the same family as peaches and cherries. Nutrition bars, teas, beer and more could all be produced from the fiber-rich fruit that's often dumped as waste.
Insight’s Vicki Gonzalez spoke with Dr. Josette Lewis, Chief Scientific Officer of the Almond Board of California to learn more about how almond upcycling could work.
This interview has been edited for clarity and length.
On what makes up the components of an almond
The almond kernel is in the inside of what looks a bit like a peach pit … the almond, the kernel inside is surrounded by a shell. Now, in an almond compared to a peach, you can crack the [almond] shell with your hands. It’s very, very soft. It’s pretty woody and surrounding that we’re outside the bit of a peach — you have the fleshy part.
In an almond, that’s called the hull. It’s very similar to a peach when it’s first developing, but then in an almond, we’d let it dry out over the course of the summer. In fact, growers hold back some water to really accelerate the drying process because that makes the hull split open and easier to get the almonds out on the inside.
On what happens to the fleshy dried-out exterior fruit of an almond after harvesting
Right now [the hulls are] fed to dairy cows here in the state of California. It does have sugars in it, so it has a really pleasant taste for the cows. Some people call it cow candy. It has fibers and phytonutrients that are food for dairy feed.
About all of the hulls currently go into the dairy industry, and that has a really important environmental benefit to the state: It reduces the amount of alfalfa that is needed to grow for dairy feed by about 400,000 acres.
If you think about the amount of water that would be needed to grow that alfalfa, it’s enough water that could provide about 2 million households for a year of water here in the state of California. So by upcycling those holes into the dairy industry, we already reduce the environmental footprint of food here in the state of California.
On the size of the almond industry in California
We’re really proud that [our] 7,600 almond growers are mostly family farms. Over 90% of those are family farms, and 70% of them are actually farming less than 100 acres.
So we have a lot of small, very traditional family farms in this industry, which is a great asset because it keeps a lot of rural towns and cities very vibrant … we [have] the largest [almond] crop acreage here in California — that’s about 1.6 million acres of almonds.
That’s because this is the ideal climate for growing almonds. California has the largest Mediterranean climate in the world, and almonds need to have cold weather in the winter to make the trees go dormant.
They sort of sleep for a little while, and then we have to have springs that aren’t super cold because the almond trees bloom really early, around Valentine's Day. We need the temperatures to be a little warmer for the bees to come out and pollinate the crops.
On deciding what to produce from almond hulls
We had a committee of folks who really wanted to look at how we could diversify the use of almond co-products and create more value back for the industry. And that committee helped us oversee a lot of different research over the last years.
We start out by looking at what’s in the almond hull, what is the composition. We know there are sugars in there, there’s fibers, or these phytonutrients.
We started out with some projects, seeing how we could extract the sugars from almond hulls and maybe use that as a food ingredient, which is possible to do. It’s feasible, but it’s not very economically competitive. Getting sugar out of the hulls versus sugar beets or sugar cane, or any of the other ways in which that ingredient is made, it’s not economically competitive.
So then we start looking at how you could treat the hulls or maybe use the hull itself as a whole ingredient — looking at how to make it into a powered format that would be more compatible as an ingredient but take advantage of the whole package of what’s in that hull.
On sample products produced from hulls
Mattson has been working with us to develop food product concepts. They started out by tasting the hulls themselves, figuring out what sort of flavor profiles were [in the hulls] and whether those might be compatible with other ingredients.
A couple of winning opportunities that we can talk about today is the idea of using powdered almond hulls as an ingredient in a nutritional bar, like a Clif Bar-type product. It adds a lot of really valuable nutrition into that product and has a good flavor.
Almond hulls have a flavor profile that has a bit of bitterness as well as some sweetness compatible with coffee. And [Mattson] roasted the almond hulls and then used it as a partial substitute for coffee beans or as a full substitute, making a sort of almond fruit tea that has a similar flair to coffee.
As someone who needs to moderate their caffeine intake, I got pretty excited about maybe a 20% replacement of my coffee beans with almond hulls, and I could maybe have an extra cup of coffee a day.