Rapid Oil Extraction from Potato Chips

Abstract

Sir: Total or crude fat determination is a common analytical technique in proximal analysis and lipid chemistry. This is done traditionally by Soxhlet or Goldfisch extraction. Both are solvent extraction methods which require hours of solvent reflux extraction. A long extraction may be necessary when lipids are well embedded into tissues and the surface area to weight ratio is low. However, many food materials may have oil that can be readily extracted without such exhaustive solvent extraction. Development of simple, practical, rapid extraction techniques would be more cost effective, particularly when dealing with large numbers of samples. Such techniques have been developed for small particle lipid bearing materials. Clark and Snyder [1] developed a rapid 1 min equilibrium extraction method of a 1‐2 g sample to determine total oil content in soy flour with hexane at ambient temperature that produced results similar to those obtained by Goldfisch extraction. This allowed the rapid screening of a large number of soybean cultivars. Similarly, total oil in 2 g of rice bran samples was obtained by a rapid 1 min hexane or isopropanol extraction that produced the same results as Goldfisch extraction [2]. This method allowed large number of rice bran samples to be quickly extracted for free fatty acid determination by wet chemistry to obtain a diffuse reflectance FTIR chemometric model of the free fatty content [3]. Similarly, the total surface oil on milled rice was determined by rapid solvent