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Changes in compositions and quality between fresh and frozen fruits in the different fruit maturity (80% colored and full ripened) in two strawberry cultivars ($quot;Bokyo$quot; and $quot;Yeohong$quot;) were compared. Fruit samples were quick freezed at -40 and stored at -20 for 5 months. In ascorbic acids, $quot;Bokyo$quot; was much higher than $quot;Yeohong$quot;, and a little amount was decreased during the frozen storage. Titratable acids were much more contained in the immature fruits than the full ripened ones, and these were declined in frozen strawberries. The contents of total soluble pectin were higher in the immature fruits, and the water soluble pectins were significantly increased in frozen strawberries regardless of maturity in $quot;Bokyo$quot;. Much higher sucrose was observed in $quot;Yeohong$quot; than $quot;Bokyo$quot;, and sucrose was decreased in frozen tissues of the immature fruits but not in ripened ones. Sixteen kinds of amino acids were detected, and amino acids were markedly decreased by freezing, The optimal thawing temperature showed at 5 to 10. The amount of drips was significantly higher in $quot;Bokyo$quot;. The off-flavor from the frozen strawberries were percepted when thawed at above 15. The amount of pelargonidin-3-monoglucoside (P-3-G) was 6 to 8 times higher than that of cyanidin-3-monoglucoside (C-3-G) in both cultivars. $quot;Yeohong$quot; contained more pigments than $quot; Bokyo$quot;. These pigments were decreased slightly during the frozen storage. $quot;Ycohong$quot; was high by graded in Color Difference Meter $quot;a$quot; value and showed a little reduction in chroma. In the structure of cell walls, middle lamella was considerably shown in the fresh fruits, whereas disappeared in frozen ones.
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