OPTIMIZATION OF HMF FORMATION IN WHITE AND RED GRAPE JUICE CONCENTRATES STORED IN VARIOUS LAMINATED FILMS USING RESPONSE SURFACE METHODOLOGY


EKİCİ L., Karacan S., Velioglu Y. S.

JOURNAL OF FOOD PROCESSING AND PRESERVATION, cilt.33, ss.313-328, 2009 (SCI-Expanded) identifier

Özet

The effect of packaging materials on the formation of 5-hydroxymethyl 2-furfural (HMF) was investigated. Red and white grape juice concentrates at 70 Brix filled into pouches from three different packaging materials including polyethylene/polyamide (PE/PA), polyethyleneterephthalate/polyethylene (PET/PE) and polyethyleneterephthalate/aluminum/polyethylene (PET/Al/PE) were stored at 28 and 37C for 6 months. HMF, browning index (A(420)) and clarity (% T-625) analyses were conducted by taking samples at 1th, 2nd, 3rd and 6th months during storage. The coefficient of determination, R-2 values for HMF formation, A(420) and % T-625 were 1.00. Statistical analysis showed that packaging materials, grape juice concentrate, storage temperature and time were significantly (P < 0.0001) correlated to HMF, A(420) and % T-625. Based on response surface and contour plots, optimum conditions for HMF formation, A(420) and % T-625 were: (PET/A1/PE) packaging materials, storage temperature of 36.53C and storage time of 1.22 months for white grape juice concentration and (PET/A1/PE) packaging materials, storage temperature of 28.12C and storage time of 5.80 months for red grape juice concentration.