Abstract
Extruded corn-soy products developed for the US AID Food for Peace program contain high levels of lipids (about 12%) and vitamins and minerals, including oxidation-sensitive vitamins A and C and iron. Because lipid stability is probably the most important factor in maintaining long-term storage stability of these products, being able to analyze lipid content and oxidation is critical. In cereals, substantial amounts of lipid are bound to starch, making cereal lipids notoriously difficult to extract. Conventional methods such as acid hydrolysis, hot water-saturated butanol, and exhaustive soxlet extractions result in damage to the lipids and thus give inaccurate measures of lipid stability. A new method of extracting lipids from cereal-based products without damage is proposed using pretreatment with α-amylase to digest the starch and release bound lipids. One gram of the product is slurried with 25 mg α-amylase in water and incubated for 16 h. Lipids are then extracted from this mixture with 2:1 (v/v) dichloromethane or chloroform:methanol. This procedure was quantitative, extracting 98.7% of the lipid, and it gave an extract suitable for analysis of fatty acid contents and lipid oxidation products, e.g. peroxide values, and carbonyl contents.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
