Squeezing Fat Out of Foods
August 27, 1997
It sounds like a dieters dream: finding a way to squeeze the fat out
of foods we love, like big juicy hamburgers.
Scientists with USDAs
Agricultural Research Service have
developed a way to do just that--not for the sake of counting calories, but for
food analysis--while reducing the steps and chemical solvents now used to
analyze foods fat content for nutritional labeling.
By teaming a technology called supercritical fluid extraction with an enzyme
called lipase, the scientists can simultaneously extract fat from hamburger
samples and complete the chemical reaction needed to release the fats. In
conventional fat analysis, the sample must first be treated with chemical
solvent to break down the bonds in the meat which hold the fat molecules in
place. Then more chemicals are required to actually extract the fat.
Supercritical fluids are highly compressed gases, such as carbon dioxide,
with densities that resemble those of liquids. In an extraction chamber, the
fluid flows through a sample and dissolves specific chemicals, or fats in the
case of food extractions. The gas is then decompressed and harmlessly vented
into the atmosphere, leaving the extracted fats behind.
Scientific contact: Janet M. Snyder, USDA-ARS
Food Quality and
Safety Laboratory, NCAUR, Peoria,
Ill.; phone 309-681-6236, email@example.com