New Edible Coating Helps Pecans Stay Fresh Longer

An edible coating that keeps pecans fresh up to 10 months in storage at room temperature could bring an end to the rancid, off-taste that sometimes spoils the nuts.

Scientists with USDA's Agricultural Research Service developed the coatings, which are made from cellulose, an all-natural product that is the most abundant polysaccharide found in nature. Commercially available and relatively inexpensive, cellulose could easily be sprayed on pecan nutmeats by processors.

Of the three cellulose derivatives tested, carboxymethyl turned out to best preserve flavor. It imparted a high gloss without causing the nuts to look or feel oily, boosting consumer appeal. The coating also delayed undesirable color changes, a potentially important feature since consumers associate dark-colored pecans with rancidity. Rancidity occurs when oxygen enters the nut and breaks down, or oxidizes, some of its fat.

Generally recognized as safe by the U.S. Food and Drug Administration, the coatings would need to be listed on the label as an ingredient. The pecan industry is interested in further developing the coatings, which could promote year-round consumption.

The coatings were developed at the ARS Citrus and Subtropical Products Research Laboratory in Winter Haven, Fla., in conjunction with the ARS Southeastern Fruit and Tree Nut Research Laboratory in Byron, Ga. ARS, USDA's chief scientific research agency, features this story in the January Agricultural Research magazine. It can be accessed on the Internet at:

/is/AR/archive/jan99/pecans0199.htm

Scientific contact: Elizabeth A. Baldwin, Citrus and Subtropical Products Research Lab, ARS, Winter Haven, Fla., (941) 293-4133, ext. 119, fax (941) 299-8678, ebaldwin@asrr.arsusda.gov or Bruce W. Wood, Southeastern Fruit and Tree Nut Research Lab, ARS, Byron, Ga., (912) 956-6421, fax (912) 956-2929, bwood@byronresearch.net.