Dryer preserves antioxidants in blueberry powder
It's well known that blueberries are good for you - rich in antioxidants and anthocyanins.
Consumption of blueberries is associated with improvement of ischemic stroke outcomes and of antioxidant capacity in blood plasma. (In ischemic stroke, blood supply to part of the brain is decreased, leading to dysfunction of the brain tissue in that area.)
In pigs, reduced levels of plasma lipids have been found in association with blueberry consumption, while rodents have been found to overcome the genetic predisposition to Alzheimer's disease.
In comparison to most other berries, blueberries have higher antioxidant activity and anthocyanin content. (Anthocyanins are the compounds that, among other things, give wine its color). Consequently, there is a large consumer demand for fresh blueberries as well as their products.
Blueberries, though, are a seasonal crop with a short shelf life as a fresh product. To meet consumer demand, fresh berries have to be either frozen or otherwise processed.
Because maintaining frozen products may be cost-prohibitive, there is a growing interest in developing cost-effective preservation methods capable of minimizing the degradation of anthocyanins in processed berry products such as powders.
Now, a technology developed by Columbia PhytoTechnology and a WSU assistant professor of food science, Kerry Ringer, takes blueberry drying to the next level. The technology meets consumer demand for highly nutritious foods and at the same time addresses industry concerns about costs.
A recently published study about the technology shows that its dried blueberry products retain as many antioxidants and anthocyanins as liquid products.
Called the Radiant Zone dryer, Columbia's technology customizes drying times and temperatures to get the best product at a reasonable cost. By using damaged or bruised fruit, the technology recovers profit from the loss columns of producers' and processors' books.
Located in rural Dallesport, Wash., Columbia hopes to play a role in the economic development of the area by dovetailing tech jobs into the area's rural economy.
"We focused on dehydration of blueberry puree, blueberry juice and blueberry extract supplied by a Washington fruit processing company," said Ringer.
"This project demonstrated the development of value-added products that potentially bolster profit margins and the types and numbers of jobs in agriculture, Washington's No. 1 industry. The Radiant Zone Dryer technology also provides options to ag producers for processing waste."