3.3.2. Relationships among SSC and Soluble Sugar Contents

Relationships among the contents of TSS, fructose, glucose, sucrose and SSC were measured on a one to one basis, and SSC presented a positive association profile with TSS, fructose, glucose and sucrose during storage at 25 and 0 ◦C (*p* < 0.05) in Tables 1 and 2. It is clear that among TSS and the three soluble sugars, sucrose had the strongest association with the changes of SSC with high corresponding *r* values of 0.973 at 25 ◦C and 0.963 at 0 ◦C. Other soluble sugars had lower contributions to the correlations with SSC, shown as a second relation with TSS and fructose, and finally glucose. The results were consistent with the report by Wei et al. [36]. It should be noted that significant positive correlations were found between TSS with three types of soluble sugars (*r* > 0.847), and fructose contributed the most to the correlation with TSS, with *r* values of 0.974 at 25 ◦C and 0.975 at 0 ◦C. This could be expected as the content of fructose comprised the largest fraction of the TSS content.


**Table 1.** Pearson- s linear correlation coefficients among SSC and soluble sugars for 50 days at 25 ◦C.

\* *p* < 0.05, \*\* *p* < 0.01, '\': without value, *n* = 60 individual apples; soluble solid content (SSC), total soluble sugars (TSS).

**Table 2.** Pearson- s linear correlation coefficients among SS and soluble sugars for 150 days at 0 ◦C.


\* *p* < 0.05, \*\* *p* < 0.01, '\': without value, *n* = 60 individual apples.
