Abstract:

The aim of this study was to evaluate the relationship between phloridzin content and quality indicators of apple
fruit. During the 180-day storage of ‘Fuji’ apples, the phloridzin content in different parts of the fruit (peel, pulp and seed)
and quality indicators (hardness, water content, and soluble solid content (SSC), titratable acidity (TA) and SSC/TA ratio)
of apple flesh were determined. Correlation analysis and regression analysis were conducted between phloridzin content and
the quality indicators. The phloridzin contents in different parts of apple fruit were in the decreasing order: seed > peel >
pulp and showed downward trends with storage time. During the fourth month of storage, apple fruit exhibited high content
of phloridzin and maintained an excellent eating quality with high hardness and sweet taste. The correlation analysis showed
that there was a positive correlation between hardness and the phloridzin content of apple peel and seed as well as between
TA and the phloridzin content of apple pulp, and a negative correlation between SSC/TA ratio and the phloridzin content
of apple pulp and seed and between water content and phloridzin content of apple seed (P < 0.05 for all measures). The
regression analysis indicated that there existed six significant regression equations between phloridzin content and quality
indicators with excellent goodness of fit. This study demonstrated that the phloridzin contents in different parts of apple fruit
could be predicted by the quality indicators.

Key words: apple, phloridzin, storage, quality indicators, correlation