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Juices of Golden Queen, Neo-Muscat and Seibell-9110 were prepared with the addition of SO₂(100ppm) in must and juice, of SO₂(100ppm) and pectinase (40㎎/ℓ) in must, respectively and then 300㎎/ℓ of Polyclar AT were added on different white wines from grape juices. Phenolics content in grape juices and white wines were determined, and also changes of browning capacity of white wines during the storage periods at 45℃ were investigated by accelerated method. Extraction of total phenol into grape juices was increased significantly in SO₂-pectinase addition lot and content of total phenol of Seibell-9110 juice was two or three times higher than the others. Yield of grape juices was highest in SO₂-pectinase addition lot. Ethanol content of white wines were 11.4-12.0 v/v%, and total acid, fusel oil and methanol content of Neo-Muscat white wine was lower than that of the other white wines. Total phenol content of white wines was 25-50% lower than that of grape juices and 50-80% lower in colour. Browning capacity of white wines was decreased by 25-40% for 18 days at 45℃ with addition of Polyclar AT, but Seibell-9110 white wine prepared from SO₂-pectinase addition lot was not available commercially because of severe browning.
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