Utah-based SPL has been in business for 30 years, but until recently it kept its grass-derived ingredients to itself, using them only in its own range of supplements.
However other companies have started to approach it with a view to using its ingredients for their own product development, which led it to develop raw materials on a larger scale.
"Only now are we letting the industry at large have access to them," CEO Mitchell May, PhD, told NutraIngredients-USA.com.
The history of grass juices goes back to the earliest days of the dietary supplement industry in the US, in the 1920s and 30s, said May. Only years later, with the advent of synthetic vitamins, did they industry start to move away from the whole foods idea.
However SPL decided to increase its production capability since the global supplements industry is returning to natural sources. It spent two years developing the CO2 process.
Grass is rich in a range of vitamins, including A (as beta-carotene), E, B12 and K, the minerals calcium, iron and magnesium, and a range of bioactive enzymes beta-galactosidase, beta-glucosidase, acid-phosphatase, alpha-mannosidase, superoxide-dismutase (SOD) and chlorophyll.
When grass is in its unjuiced form, the nutrients are not bioavailable to humans since they are bound up in cellulose.
"We don't produce the enzyme cellulase, that is needed to break it down," said May, who went on to point out that big, strong creatures like horses, cows and elephants glean the majority of their nutrition from grass, having the gastrointestinal design to cope with it.
The only way that the potency can be unlocked for humans is by taking the nutrients out of the cell wall. Since they are very vulnerable to heat and oxygen, the juice must be made stable by drying and preserving.
Many of the grass products on the market are either whole grasses, or use heat or oxygen to extract the active compounds, which destroys some of the value.
The only two processes that preserve the nutrients are CO2 extraction or freeze-drying, said May. His company opted for the latter because freeze-drying must be done in batches. For every 1000 kg of grass put into the freeze dryer, just 50lb of powder comes out - and the process takes 40 hours.
With CO2 extraction, on the other hand, the process is much faster and can be run continuously throughout the day.
"It yields and superior product at an equal price," said May, who believes that SPL is the only company to have developed a CO2 process.
The process is proprietary rather than patented, since the way it would be articulated in a patent application would mean that a portion could be infringed upon, without the patent itself being infringed.
Fifty kilograms of grass blades, each one 17cm in height, are required to make just one teaspoon of powder.
May explained that 17cm is the optimal height for harvesting, since the nutrient levels greater in young grass. Once it surpasses that height, the levels start to drop. Moreover, the nutrient levels do not differ from grass variety to grass variety. SPL offers powders from wheat grass, oat, barley, kamut and alfalfa.
The grass must be juiced within two to three hours of harvesting, to prevent nutritional loss. The company uses SOD as a measure of degradation, since it is one of the most sensitive antioxidants present in grass. "If the SOD is fully active, then the grass is as it would be in its fresh state," said May.
To ensure speedy transfer from field to plant, the company has several hundred acres of organic ground surrounding its processing facility, and it uses only heirloom seeds.
There are two harvests a year - one in late spring to early June, and the other in the fall - yielding 100,000 kg of product per year.
The vacuum-packed powders, which have a shelf-life of two years once processed, are soluble in liquid and can be used for powdered drink mixes or smoothies, tablets or capsules and bar applications.