New Procedure Analyzes Fat
Structures in Foods
By Linda McGraw
July 5, 2000
A new analytical technique developed by
Agricultural Research Service scientists
simplifies the complex, time-consuming task of predicting how certain fats will
change during processing and storage. This could lead to margarines,
shortenings and cooking oils with good taste and a longer shelf life--good news
for consumers and food manufacturers alike.
Food manufacturers have to determine how certain fats, called triglycerides,
will act in food formulations and during storage. Thats because these
fats play a key role in flavor and texture. Now, costly trial-and-error
analytical procedures for triglycerides can take months.
As an alternative, ARS chemist William E. Neff and
Florida-Atlantic University researcher W.
Craig Byrdwell, formerly with ARS, developed an analytical technique to help
food manufacturers shave months off product development. The two researchers
worked together at ARS National
Center for Agricultural Utilization Research in Peoria, Ill.
The new technique is a scientific mouthful--reversed-phase high-performance
liquid chromatography (HPLC)/atmospheric pressure chemical ionization (APCI)
with mass spectrometry (MS). It sounds complicated, but HPLC/APCI-MS actually
simplifies identifying triglycerides.
Seed oils--canola, corn, soybean and sunflower--are a complex mixture of
triglycerides. Mass spectrometry helps the researchers identify each individual
triglyceride. APCI-mass spectrometry breaks fat molecules into a few large
pieces. The researchers can see intact triglycerides before they break down to
form negative byproducts during storage or high- temperature frying. The
technique is especially helpful for evaluating sunflower and soybean oils,
which have no standard reference for their chemical composition.
Using the new technique, the scientists identified 35 to more than 100
triglycerides in just two hours. The technique also correlate triglyceride
composition with the physical properties it imparts to food: melting range,
mouth-feel and reaction to refrigeration. This should be good news for food
manufacturers and to consumers in their quest for healthful, better-tasting
ARS is USDAs chief scientific
Scientific contact: Gary R. List,
Food Quality and
Safety Research, ARS National Center for Agricultural Utilization Research,
Peoria, Ill.; (309) 681-6388, fax (309) 681-6679,