| Title: | Influence of storage on volatile profiles in roasted almonds (Prunus dulcis) |
| Author(s): | Lee J; Xiao L; Zhang G; Ebeler SE; Mitchell AE; |
| Address: | "Department of Food Science and Technology and double daggerDepartment of Viticulture and Enology, University of California, Davis , One Shields Avenue, Davis, California 95616, United States" |
| ISSN/ISBN: | 1520-5118 (Electronic) 0021-8561 (Linking) |
| Abstract: | "Hexanal, peroxide value, and lipid hydroperoxides are common indicators of lipid oxidation in food products. However, these markers are not always reliable as levels are dynamic and often can be detected only after significant oxidation has occurred. Changes in the volatile composition of light- and dark-roast almonds were evaluated during storage over 24 weeks at 25 or 35 degrees C using headspace solid phase microextraction (HS-SPME) gas chromatography-mass spectrometry (GC-MS). Several volatile changes were identified in association with early oxidation events in roasted almonds. Hexenal decreased significantly during the first 6 weeks of storage and did not increase above initial levels until 20-24 weeks of storage depending upon the degree of roast. In contrast, levels of 1-heptanol and 1-octanol increased at 16-20 weeks, depending upon the degree of roast, and no initial losses were observed. Seventeen new compounds, absent in raw and freshly roasted almonds but detectable after 6 weeks of storage, were identified. Of these, 2-octanone, 2-nonanone, 3-octen-2-one, 2-decanone, (E)-2-decenal, 2,4-nonadienal, pentyl oxirane, and especially acetic acid increased significantly (that is, >10 ng/g). The degree of roasting did not correlate with the levels of these compounds. Significant decreases in roasting-related aroma volatiles such as 2-methylbutanal, 3-methylbutanal, furfural, 2-phenylacetaldehyde, 2,3-butanedione, 2-methylpyrazine, and 1-methylthio-2-propanol were observed by 4 weeks of storage independent of the degree of roast or storage conditions" |
| Keywords: | Cooking Food Storage Gas Chromatography-Mass Spectrometry Plant Extracts/*chemistry/isolation & purification Prunus/*chemistry Solid Phase Microextraction Volatile Organic Compounds/*chemistry/isolation & purification Gc-ms Hs-spme Prunus dulcis almonds h; |
| Notes: | "MedlineLee, Jihyun Xiao, Lu Zhang, Gong Ebeler, Susan E Mitchell, Alyson E eng Research Support, Non-U.S. Gov't 2014/10/28 J Agric Food Chem. 2014 Nov 19; 62(46):11236-45. doi: 10.1021/jf503817g. Epub 2014 Nov 11" |
