Dynamic changes in the volatiles and sensory properties of chilled milk during exposure to light. (November 2016)

• Record Type: Journal Article
• Authors: Zardin, Erika; Silcock, Patrick; Siefarth, Caroline; Bremer, Phil J.; Beauchamp, Jonathan
• Is Part Of: International dairy journal. Volume 62(2016:Nov.)
• Page Start: 35
• Page End: 38
• Publication Date: 2016-11
• Subjects: Dairying -- Periodicals; Industrie laitière -- Périodiques; Electronic journals; 338.1762142
• DOI: 10.1016/j.idairyj.2016.07.005
• Languages: English
• ISSNs: 0958-6946

Abstract

Abstract: Exposure of milk to light causes photo-oxidation and off-flavour generation. To characterise these reactions, semi-skimmed (1.5% fat) and whole (3.8% fat) extended shelf-life cows' milk were exposed to light for 20–48 h at 4 °C and volatiles in the milk headspace were measured on-line using proton-transfer-reaction mass spectrometry (PTR-MS). The flavour of the whole-milk was assessed by aroma profile analysis on both orthonasal/retronasal odour and taste after 0, 0.25, 1, 6 and 24 h light-exposure. Sensory changes perceived in milk exposed to light for up to 6 h varied in intensity and between replicates, most notably a transient sensory defect being detectable after 0.25 h exposure, but these changes did not correspond to any volatile organic compound (VOC) generation detected by PTR-MS. After 24 h, several compounds showed enhanced release profiles. Principal components analysis related these VOCs to changes in the sensory properties of the milk, described as oxidised / rancid / hay-like .