Inhibition of key aroma compound generated during ultrahigh-temperature processing of bovine milk via epicatechin addition.
The ability of epicatechin (EC) to inhibit the thermal development of aroma compounds (i.e., Maillard reaction products) formed during ultrahigh-temperature (UHT) processing of bovine milk was evaluated. Volatile extracts were prepared for two UHT-processed milk samples made from (1) raw milk and (2) raw milk containing 0.1% EC by solvent-assisted flavor evaporation (SAFE) and subsequently analyzed by aroma extract dilution analysis (AEDA). Sensory evaluation was also conducted by a trained panel on the intensity of cooked flavor and bitterness in four UHT-processed milk samples (0.00, 0.01, 0.10, and 0.20% EC added prior to processing), as well as a commercial pasteurized milk sample for comparison. AEDA indicated that addition of EC to raw fluid milk prior to UHT processing reduced the overall thermal formation of key aroma-active compounds in comparison to the traditional UHT milk sample. The largest changes in FD values were reported for methional, furfural, 2-isopropyl-3-methoxypyrazine, 2-acetyl-1-pyrroline, and 2-acetyl-2-thiazoline (Maillard-type aroma compounds) with 32-, 8-, 8-, 4-, and 4-fold reductions in formation, respectively. Sensory evaluation also revealed that all EC-containing UHT milk samples had statistically (P < 0.05) lower cooked flavor intensity in comparison to the control, whereas the 0.2% EC sample was statistically similar to a pasteurized milk sample. Furthermore, addition of EC at or below 0.1% in UHT fluid milk did not significantly increase the bitterness intensity.
Colahan-Sederstrom
Paula M
PM
Department of Food Science, 215 Borland Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802-2504, USA.
Peterson
Devin G
DG
D000818:Animals; D002392:Catechin / Q000008:administration & dosage*; D002417:Cattle; D005511:Food Handling / Q000379:methods; D006358:Hot Temperature; D006801:Humans; D008892:Milk / Q000737:chemistry*; D009812:Odorants / Q000032:analysis*
D002392:Catechin