Effects of thermal pasteurization on quality of Kozan yerlisi (Kozan local orange) and Hamlin orange juices

At this work, we researched that effects of different pasteurization temperatures (75, 80 and 85 oC) on carotenoids, phenolic compounds, ascorbic acid, antioxidant activity, sensory quality, total phenolic compound, hydroxyl methyl furfural (HMF) and color parameters of Hamlin and Kozan Yerlisi (Kozan Local Orange) orange juice. According to results of color analyses, there was not found important differences between control and pasteurized juice samples when varieties of orange juice were evaluated in different groups. The highest value of HMF was found in pasteurized at 85 oC of Kozan Yerlisi (Kozan Local Orange) orange juices. The differences of antioxidant activity samples were not evaluated as important between varieties and applications. Ascorbic acid content were between 353.05 and 480.8 mg/l in Hamlin orange juices and between 1017.17 and 1060.35 mg/l in Kozan Yerlisi orange juices. According to results, naringin was found as major flavonoid in Hamlin orange juices (51.69?89.00 mg/l) but in Kozan Yerlisi (Kozan Local Orange) orange juices, hesperidin was determined as major flavonoid (63.08?73.87 mg/l). The major carotenoids of Hamlin and Kozan Yerlisi (Kozan Local Orange) orange juices were xantophyll ?? (% 36) ve ß-carotene (% 33), respectively and the principal losses among carotenoids were observed in ß-carotene (% 18.2) and ß-apo-carotenal (% 19.6), respectively. In accordance with sensory analyses, Kozan Yerlisi (Kozan Local Orange) was the most desirable variety.