Can Almonds Become a Zero Waste Crop?
06 Jan 2017 --- The Almond Board of California (ABC) has announced it is currently looking for ways to optimize almond co-products such as almond hulls, shells and other woody materials in order to reduce food waste.
Changing market needs for these products has led the ABC to focus research investment on new uses which address manufacturing needs across several industries, among them food, automotive, pharmaceutical, cosmetics and plastics. This brings value to the California almond community, the economy, the local environment, and supports almonds on their journey to zero waste.
From almond hulls and shells to cosmetics, foods, pharmaceuticals and plastics
Almond shells can be heated to high temperatures, producing a charcoal-like product, which has the potential to be used to create stronger, biodegradable plastics such as rubbish bags, flower pots and rubber tyres.
Existing research has already shown how sugar can be extracted from almond hulls, which has potential applications as a food ingredient or a fuel. Once the sugar is extracted, spent hulls remain and Almond Board research is focused on exploring the ways to use this material. One example is using fermentation by which they can be converted to make fibrous materials that can be added to baby nappies as a natural absorbent or as additives for foods, moisturisers and pharmaceuticals.
Whole orchard recycling for healthy soil
This process, of grinding up entire almond orchards at the end of their mature life and incorporating the trees’ material into the soil, has significant potential benefits for soil health. These include: returning nutrients to the soil; improving soil quality, air quality, water infiltration and water-holding capacity; and slowing the rate at which carbon dioxide is released into the atmosphere, prolonging the carbon sequestration benefits that trees bring to our planet.
Like almonds, almond hulls are high in important nutrients which position them as a valuable soil amendment and source of organic matter. In addition to research about them being spread directly into the orchard as a soil conditioner, the spent almond hulls left over from sugar extraction can be heated to high temperatures to produce a product similar to charcoal, known as biochar, which can be spread on all farms, leading to improvements in soil quality and water-holding capacity.
For decades the California Almond community has utilised almond coproducts, which include the hulls and shells that protect the nut during its development as well as the woody biomass of the tree itself, in a responsible, sustainable fashion, often yielding secondary benefits. Currently, the hulls are sold as nutritious livestock feed, the shells are used as livestock bedding and the tree woody material can be used to create alternative energy. In 2015, the California almond industry grew 1.9 billion pounds of almond kernels as well as 3.8 billion pounds of hulls and 1.3 billion pounds of shells.
