Journal of Food Lipids 12 (2005) 12–22. All Rights Reserved. 12 © Copyright 2005, Blackwell Publishing TURBIDIMETRIC LIPID ASSAY IN SEED FLOURS GABI DROCHIOIU 1 Biochemistry Laboratory Chemistry Faculty “Al. I. Cuza” University of Iasi 11 Carol I, RO-700506 Iasi, Romania Received for Publication February 9, 2004 Accepted for Publication September 29, 2004 ABSTRACT A simple, fast, sensitive and accurate turbidimetric assay of lipids in the milled seeds was developed. The procedure is based on the extraction of lipids into acetone followed by their turbidimetric reaction with a 1.5% solution of sulfosalicylic acid and turbidimetric measurements. The spectral measure- ment was made at 440 nm against a blank of the reagents. A standard curve was constructed using raw fat extracted from the species being analyzed. For analysis of a large number of solvents, the standardization of the turbidimetric method may be accomplished using Soxhlet values for a few representative samples. A negative relationship between the hardness of maize particles and their content of raw fat was observed. INTRODUCTION Lipids are very important components of plant seeds that are customarily determined by solvent extraction in a Soxhlet or a similar apparatus (Drochioiu 1999). Currently, hexane is most commonly used for oil extraction from oilseeds. However, due to its toxicity and inflammability, the use of hexane is strictly regulated. Ethanol is being studied as a possible replacement for hexane, but ethanol also dissolves certain proteins and carbohydrates in seeds. Acetone has been shown as a potential solvent for Soxhlet extraction. Therefore, conventional Soxhlet-type extraction uses flammable solvents and is time-consuming. Furthermore, the oil content is determined gravimetrically after solvent evaporation (Hechler et al. 1995). All solvent extraction proce- dures require several grams of dried sample and consequently the determina- Blackwell Science, LtdOxford, UKJFLJournal of Food Lipids1065-7258Copyright 2005 by Food & Nutrition Press, Inc., Trumbull, Connecticut.1211222Original ArticleTURBIDIMETRIC LIPID ASSAY IN SEED FLOURSG. DROCHIOIU 1 Corresponding author. TEL: +40-232-201278; FAX: +40-232-201313; EMAIL: gabidr@uaic.ro