Title: Effect of extraction method on quality of orange juice: hand-squeezed, commercial-fresh squeezed and processed Authors
|Ford, Bryan -|
Submitted to: Journal of the Science of Food and Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 5, 2011
Publication Date: June 27, 2012
Citation: Baldwin, E.A., Bai, J., Plotto, A., Cameron, R.G., Luzio, G.A., Narciso, J.A., Manthey, J.A., Widmer, W.W., Ford, B.L. 2012. Effect of extraction method on quality of orange juice: hand-squeezed, commercial-fresh squeezed and processed. Journal of the Science of Food and Agriculture. 92:2029-2042. Interpretive Summary: Fresh orange juice is perceived to be more wholesome and flavorful than processed juice, and in this study, oranges were extracted using a commercial food service juicer, pasteurized or not, resulting in fresh commercial juice, pasteurized fresh commercial juice (to kill microbes), gently hand-squeezed juice or pasteurized processed juice to mimic commercial products. The juice from the commercial food service juicer had a high amount of peel oil compared to the other juices, giving this juice more aroma volatiles that partly masked the peel oil taste. Normally, a high amount of peel oil is not well liked in processed juice, which already has a “cooked” flavor. The peel oil may also result in added health benefits which will be reported in a companion paper. Nevertheless, the gently hand-squeezed juice was most preferred by taste testers.
Technical Abstract: Fresh orange juice is perceived to be more wholesome than processed juice. Fresh juice may have flavor and nutrients that differ from pasteurized or processed juice. In this study, ‘Hamlin’ and ‘Valencia’ oranges were extracted using a commercial food service juicer, pasteurized or not, resulting in fresh-commercial juice (FCJ) or pasteurized juice (FCPJ) for comparison with pasteurized processed juice (PPJ) in 2009, and gently hand-squeezed’ Valencia’ juice (HSJ) in 2010 for quality attributes. There was higher peel oil, lower pectin content, and less cloud loss in FCJ/FCPJ compared to PPJ and FCJ than PPJ regardless of pasteurization. Ascorbic acid was higher for PPJ; titratable acidity was higher and the ratio of solids to acids lower in FCJ /FCPJ or HSJ compared to PPJ. FCJ/FCPJ had generally more aroma volatiles than PPJ and overall, the highest esters, terpene alcohols, methanol and ethanol levels were in HSJ. For sensory, FCJ/FCPJ had more peel oil and PPJ more cooked flavor than other samples while ‘Valencia’ HSJ was preferred over the other juices. In conclusion, high peel oil content and thermo-pasteurization process decreased cloud loss of orange juice. Extraction and finishing processes rather than pasteurization or oil content were major factors in influencing orange juice flavor quality.