Title: | "Off-flavor related volatiles in soymilk as affected by soybean variety, grinding, and heat-processing methods" |
Author(s): | Zhang Y; Guo S; Liu Z; Chang SK; |
Address: | "Department of Food Science, Nutrition and Health Promotion, Mississippi State University , MS State, Mississippi 39762, United States" |
ISSN/ISBN: | 1520-5118 (Electronic) 0021-8561 (Linking) |
Abstract: | "Off-flavor of soymilk is a barrier to the acceptance of consumers. The objectionable soy odor can be reduced through inhibition of their formation or through removal after being formed. In this study, soymilk was prepared by three grinding methods (ambient, cold, and hot grinding) from two varieties (yellow Prosoy and a black soybean) before undergoing three heating processes: stove cooking, one-phase UHT (ultrahigh temperature), and two-phase UHT process using a Microthermics direct injection processor, which was equipped with a vacuuming step to remove injected water and volatiles. Eight typical soy odor compounds, generated from lipid oxidation, were extracted by a solid-phase microextraction method and analyzed by gas chromatography. The results showed that hot grinding and cold grinding significantly reduced off-flavor as compared with ambient grinding, and hot grinding achieved the best result. The UHT methods, especially the two-phase UHT method, were effective to reduce soy odor. Different odor compounds showed distinct concentration patterns because of different formation mechanisms. The two varieties behaved differently in odor formation during the soymilk-making process. Most odor compounds could be reduced to below the detection limit through a combination of hot grinding and two-phase UHT processing. However, hot grinding gave lower solid and protein recoveries in soymilk" |
Keywords: | "Aldehydes/analysis Chromatography, Gas Food Handling/*methods Furans/analysis Hexanols/analysis Hot Temperature Ketones/analysis Lipoxygenase/metabolism Odorants/analysis Solid Phase Microextraction Soy Milk/*chemistry Soybean Proteins/analysis Soybeans/*;" |
Notes: | "MedlineZhang, Yan Guo, Shuntang Liu, Zhisheng Chang, Sam K C eng 2012/07/21 J Agric Food Chem. 2012 Aug 1; 60(30):7457-62. doi: 10.1021/jf3016199. Epub 2012 Jul 19" |