Interaction effect of LED color temperatures and light-protective additive packaging on photo-oxidation in milk displayed in retail dairy case.

Effect of varied LED color temperatures on photo-oxidation in 2% fat milk and protection efficiency of packaging with and without light-protective additives (LPA) under different color temperatures was firstly evaluated. Riboflavin (Rb) is one of the critical photo-sensitizers in 2% milk when exposed to LED light. Higher color temperature with higher relative intensity of Rb absorbance region resulted in lower Rb and vitamin A retention, lower dissolved oxygen content, and higher TBARS value in milk packaged with non-LPA packaging. Yellow pigmented packaging that completely blocked the Rb absorbance region of all three LED color temperatures successfully reduced the rate of degradation of milk nutrients and flavor. TiO2-added packaging partially block the destructive light wavelength; higher level of TiO2 provided a longer protection on milk freshness. Combination of appropriate LED color temperature and LPA-packaging provided a cost-effective solution for minimizing photo-oxidation in retail dairy case.