Sunlight oxidized flavour

Homogenization markedly reduces the propensity to oxidative rancidity, perhaps due to redistribution of the susceptible lipids and pro-oxidants of the MFGM (however, the propensity to hydrolytic rancidity and sunlight oxidized flavour (due to the production of methional from methionine in protein) is increased). 

Unsaturated bonds in fatty acids can undergo riboflavin-photosensitized cis-trans isomerization. Lipid oxidation is also an important reaction which is catalysed by riboflavin and light and, together with the deamination of methionine to form methanal and dimethyl sulfide, it plays a major role in the development of light-induced oflf-flavour in milk. The demise of the home delivery of milk in glass bottles and the employment of alternative package materials, such as paper carton, reduced the incidence of sunlight-flavoured milk. 

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