Value Added

A scientist at Virginia Tech has found a way to grow heart-healthy omega-3 fatty acids using a byproduct of the emerging biodiesel industry.

High energy prices have led to an increase in biodiesel production, which in turn has led to an increase in the amount of a byproduct known as “crude glycerol.” Biodiesel plants leave behind approximately 10 percent crude glycerol during the production process.

The price of glycerol, a chemical compound widely used in the pharmaceutical and cosmetic industries, has consequently declined and the market can no longer absorb all the extra product. Biodiesel producers are struggling to find alternative means for disposing of crude glycerol, which is prohibitively expensive to purify for industry use.

Zhiyou Wen, assistant professor of biological systems engineering at Virginia Tech’s College of Agriculture and Life Sciences, has developed a novel fermentation process using microalgae to produce omega-3 fatty acids from crude glycerol.

“We have shown that it is possible to use the crude glycerol byproduct from the biodiesel industry as a carbon source for microalgae that produce omega-3 fatty acids. After thorough chemical analysis, we have also shown that the algae biomass composition has the same quality as the commercial algae product.”

After growing the algae in the crude glycerol, researchers can use it as an animal feed. This mimics a process in nature in which fish, the most common source of omega-3 fatty acid for humans, eat the algae and then retain the healthful compounds in their bodies. Humans who consume the fish in turn consume the omega 3s. Fish-derived products such as fish oil are an inexpensive alternative, but the taste has deterred widespread use.

The typical American diet often lacks omega-3 fatty acids despite clinical research that shows their potential human health benefits.

Wen has partnered with Steven Craig, senior research scientist at Virginia Cobia Farms to use crude glycerol-derived algae as a fish feed.

“The results so far have been promising. The fish fed the algae had significant amounts of omega-3 fatty acids.”

Wen presented his paper, “Production of omega-3 polyunsaturated fatty acid from biodiesel-waste glycerol by microalgal fermentation,” at the 236th national meeting of the American Chemical Society.

With its strong antibacterial properties, honey can reduce pain and odor in wounds.

A wound dressing that uses sterilized Manuka honey in calcium alginate has been tested and found effective at the Billings Health and Rehabilitation in Billings, Montana. Karen Zulkowski, Montana State University associate professor of nursing and student Jayme Day will present their findings this summer at the World Union of Wound Healing Societies conference in Toronto, Canada.

Calcium alginate was added to the honey to retain moisture so that the dressing would not stick to the wound, but help remove dead tissue.

Honey wound dressings have been used in Australia, New Zealand and parts of Europe.

Source: Montana State University News Service

One hundred percent of distiller’s dried grains with solubles (DDGS), a byproduct of ethanol production, can be pelletized without adding a binding agent or anything else, according to Agricultural Research Service (ARS) scientists.

DDGS is the protein, fat, fiber, unconverted starch and ash left over after ethanol production.

ARS scientists have turned DDGS from corn-based ethanol production into high-quality pellets using processing equipment at a commercial feed mill. The heating used in pelletizing did not harm the high-protein, low-starch nutrient content.

Cattle feed is currently the primary outlet for distiller’s grain, but other livestock such as swine and poultry can also eat it. To date, there are no commercial DDGS pellets available for livestock, which limits the byproduct’s use in rangeland settings.

Fish raised for food in the growing aquaculture industry eat pelletized feed, but those pellets contain commercial fish meal as a protein source, not the less-expensive distiller’s grain. ARS scientists are experimenting with adding soy and corn flour to distiller’s grain to produce pelletized feeds.

This pelletizing work promises to solve a growing problem of product deterioration–as well as hardening and caking problems during shipping and storage, which can clog the various chutes and bins that DDGS flows through. With an increasing supply of the byproduct, ethanol plants have to ship it greater distances to reach markets.

South Dakota, one of the country’s biggest ethanol-producing states, expects to produce a billion gallons of ethanol to fuel vehicles next year — about the entire nation’s production in 1999. Today, nationwide ethanol production is more than five billion gallons a year, and that amount will increase as new plants come online.

Ethanol plants are spreading outside of the Corn Belt, with plants now in New York and California, for example.

Source: Agricultural Research Service, USDA