Pattern Recognition Analysis for Volatile Compounds of the Whole, Skim, UHT-, HTST-, and LTLT-Milk under LED Irradiations

The objective of this study was to analyze the pattern recognition of volatile compounds from different types of milk underLED (Light Emitting Dioxide) irradiation for 6 d. Yellow, red, blue, dark, and fluorescent light were produced using LEDequipment. A mass spectrometry-based electronic nose and DFA (discriminant function analysis) were used to determinethe change in volatiles from different types of milk under LED irradiation. As the LED exposure time was increased, DF1of whole milk changed considerably under blue light, while that of skim milk changed significantly under red and yellowlight irradiation. Among the types of milk tested, the most light-induced oxidation sample was LTLT milk under blue light.The volatile compounds that were shown to increase due to LED treatment in the electronic nose analysis, which was basedon MS, were mainly acetaldehyde, propanal, pentanal, hexanal, heptanal, nonanal, 3-methyl butanal, 2-methyl propanal, 2-butanone, 2-pentanone, 2-hexanone, and 2-heptanaone and 2-nonanone. Key words: light emitting dioxide, volatile compound, milk, electronic nose