Optimization of microwave-assisted extraction of cottonseed oil and evaluation of its oxidative stability and physicochemical properties.

Microwave assisted extraction (MAE) is a novel method, which can reduce the extraction time and solvent consumption. This study aimed to evaluate the influence of MAE on oxidative stability and physicochemical properties of cottonseed oil. We found that the optimum extraction conditions were: irradiation time 3.57 min; cottonseed moisture content 14% and cottonseed to solvent ratio 1:4, which resulted in an extraction efficiency of 32.6%, 46 ppm total phenolic content, 0.7% free fatty acids, peroxide value of 0.2 and 11.5 h of Rancimat oxidative stability at 110 °C. GC analysis for MAE cottonseed oil determined palmitic acid (23.6%), stearic acid (2.3%), oleic acid (15.6%) and linoleic acid (55.1%), which were not significant different (P>0.05) than conventionally-extracted (control) cottonseed oil. MAE oil samples from whole cottonseed (without dehulling) had the greatest long-term stability, more than oil samples containing BHT.

[1]  S. Azadmard‐Damirchi,et al.  Effect of pretreatment with microwaves on oxidative stability and nutraceuticals content of oil from rapeseed , 2010 .

[2]  G. Buchbauer,et al.  Characterisation of various grape seed oils by volatile compounds, triacylglycerol composition, total phenols and antioxidant capacity. , 2008, Food chemistry.

[3]  Michael Komaitis,et al.  Application of microwave-assisted extraction to the fast extraction of plant phenolic compounds , 2008, LWT - Food Science and Technology.

[4]  I. G. Zigoneanu,et al.  Determination of antioxidant components in rice bran oil extracted by microwave-assisted method. , 2008, Bioresource technology.

[5]  W. C. Brumley,et al.  Reactions of antioxidants in foods. , 1986, Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association.

[6]  S. Jun,et al.  Design of U-Column Microwave-Assisted Extraction System and Its Application to Pigment Extraction from Food , 1998 .

[7]  Jan Pokorny,et al.  Antioxidants in food : practical applications , 2001 .

[8]  C. Akoh,et al.  Food Lipids: Chemistry, Nutrition, and Biotechnology , 1998 .

[9]  H. Kadi,et al.  Kinetics study of microwave-assisted solvent extraction of oil from olive cake using hexane: comparison with the conventional extraction. , 2010 .

[10]  Frank D. Gunstone,et al.  Vegetable Oils in Food Technology: Composition, Properties, and Uses , 2002 .

[11]  F. Shahidi,et al.  Bailey's Industrial oil and fat products , 2005 .

[12]  M. D. Luque de Castro,et al.  Focused microwave-assisted Soxhlet extraction: an expeditive approach for the isolation of lipids from sausage products , 2003 .

[13]  S. Jafari,et al.  The influence of cooking process on the microwave-assisted extraction of cottonseed oil , 2015, Journal of Food Science and Technology.

[14]  S. Jafari,et al.  Microwave-assisted extraction of phenolic compounds from olive leaves; a comparison with maceration. , 2011 .

[15]  D. Firestone,et al.  Official methods and recommended practices of the American Oil Chemists' Society , 1990 .

[16]  S. Jafari,et al.  The effect of natural antioxidants extracted from plant and animal resources on the oxidative stability of soybean oil , 2014 .

[17]  S. Jafari,et al.  Application and stability of natural antioxidants in edible oils in order to substitute synthetic additives , 2015, Journal of Food Science and Technology.

[18]  Huizhou Liu,et al.  Microwave-assisted extraction of tea polyphenols and tea caffeine from green tea leaves , 2003 .

[19]  V. Camel.  Microwave-assisted solvent extraction of environmental samples , 2000 .

[20]  D. Boldor,et al.  Continuous microwave-assisted isoflavone extraction system: design and performance evaluation. , 2010, Bioresource technology.

[21]  S. Jafari,et al.  Antioxidant Effect of Microwave-assisted Extracts of Olive Leaves on Sunflower Oil , 2012 .

[22]  D. C. Esveld,et al.  Microwave-assisted extraction kinetics of terpenes from caraway seeds , 2005 .