Effect of Menthol Absorption by Packaging Material on the Quality of Yogurt Drink during Storage Time

Abstract

Interaction of menthol with polyethylene terephthal ate bottles during storage time was tested at three different temperatures. Menthol is a mint flavor agent added to yogurt drinks in Iran and is considered as a factor affect ing consumer acceptance. Absorption of menthol to packaging material could cause a loss of quality in the final product due to diminished flavor intensity. Tests were done on the effects of environmental conditions (storage for three months at temperatures of 4, 25, and 45°C) on flavor stability of yogurt drink samples. Absorbed flavor was extracted from P ET bottles after the specified time periods and quantified using gas chromatography cou pled with FID detector. Then, the diffusion coefficient of menthol into PET bottles ( D p ) was determined using concentrations of absorbed menthol. Results showed different absorption levels under various conditions. After 90 days, the absorption q uantities at 4, 25, and 45°C were 38.21, 186.66 and 700.50 ng g -1 of PET bottle, respectively. It was concluded that amounts of menthol absorption into PET bottles increased with storage time and higher temperature. Elevation of storage temperature resulted in signif icant increase in diffusion coefficient of menthol in PET bottle.