Kevin Brady
Advisor: Dr. M. Karwe
April 5, 2002
Department of Food Science
MS Seminar-Plan A
Effect of thermal processing on changes in nutraceutical potential of quinoa
Quinoa (Chenopodium quinoa), a pseudo-cereal with a history dating back to the pre-Colombian Andean people, has been recently identified to have promising potential in overcoming the world’s food shortage and has been considered as a potential crop for NASA’s Controlled Ecological Life Support System. This plant can bear the utmost barren cultivation conditions while providing a high nutrition content as well as great usability of the whole plant. Processed quinoa seeds can be used to provide humans with a more nutritionally balanced diet with a potentially positive influence on optimal health.
The objective was to investigate and quantify the effect of thermal processing on the nutraceutical potential in quinoa.
Extrusion, steam preconditioning, roasting, and baking processes were applied to quinoa flour. Processed samples were subjected to successive extractions with methanol and ethyl acetate. Reverse phase HPLC, GC, and NMR spectroscopy were utilized to identify key nutraceuticals.
HPLC analysis of steam preconditioned samples showed insignificant changes in the nutraceutical profile of quinoa. HPLC analysis of extruded samples indicated process enhanced compounds. NMR spectroscopy revealed the presence of conjugated linoleic acid (CLA) in the extrusion enhanced compounds. GC analysis of extruded and raw quinoa confirmed the strong presence of regular linoleic acid, which has been suggested as a potential precursor for the formation of the conjugated isomers. Roasting and baking experiments indicated significant changes in the nutraceutical profile.
Preliminary results illustrate an increase in the nutraceutical potential of quinoa after processing. CLA compounds were increased during extrusion, and CLAs have been shown to possess many health benefits including inhibition of tumors and atherosclerosis. Identification of select processes and processing parameters enable the industry to deliver a value added product to the consumer and market. Future work will focus on reproducing preliminary results as well as investigating the effects of alkaline treatment on quinoa flour.
References:
Bruin, A. 1963. Investigation of the food value of quinua and canihua seed. Journal of Food Science. 29:872-876.
Mundigler, N. 1998. Isolation and determination of starch from amaranth (Amaranthus cruentus) and quinoa (Chenopodium quinoa). Starch/Starke. 50(2), p. 67-69.
Yangzhou, J. and Kuhn, M. 1999. Characterization of Amaranthus cruentus and quinoa Chenopodium quinoa starch. Starch/Starke. 51(4):116-120.