Isolation, identification and sensory properties of meaty precursors in beef.

摘要

Meat flavor is a complicated system. There is no one single volatile compound associated with the absolute flavor of cooked meat. It is believed that the low molecular weight components (M.W. {dollar}<{dollar} 10,000) in meat may have the potential to contribute to meaty flavor. The hypothesis in this study was that some low molecular weight components in meat muscle have the potential to contribute to meaty aroma during heat processing. The objective was to isolate and identify these low molecular weight precursors from beef tenderloin.; Beef tenderloins were aged at 2{dollar}spcirc{dollar}C for 8 days. The visible adipose and connective tissues were removed. The ground beef was treated with papain and bromelain for enzyme digested samples. The water soluble components (WSC) were extracted from both raw and enzyme-digested beef samples. The WSC were loaded onto a size exclusive column and the fractions collected. Carbohydrate, fatty acid, and peptide analyses were performed. Fractionated samples were heated to boiling point for 2 hrs for sensory evaluations and the volatiles were analyzed by GC/MS.; Seven peaks with a molecular weight under 10,000 D were found in the enzyme digested samples. The volatiles generated from peak #4 had an intensive meaty and brothy aroma and peak #7 had a strong rubbery or sulfur odor. Peak #4 consisted of pentose, palmitic acid, 3 major peptides, and amino acids. Peak #7 consisted of C8:0 fatty acid and 2 major peptides, and amino acids. The same peaks also were found in raw beef tenderloins except the quantities were less than those in enzyme-digested beef. From the sensory analysis, peak #4 had the highest scores in meaty-like and brothy categories. Peak #7 almost had no meat-like aroma but it had a strong rubbery or sulfur aroma. The combination of these two peaks produced a typical meaty aroma. Lipid degradation products were the major volatiles in all samples. A total of 55 and 40 volatile compounds were identified from peak #4 and peak #7.; Results showed that meaty aroma can be generated from the peptide-specific Maillard reactions with fatty acids, and they could be the key to access the secret of meat flavor.