International Journal of Horticulture, 2016, Vol.6, No.26, 1-8
7
2.7 Total soluble solids (
0
Brix)
At maturity stage, highest TSS was noticed in Golden delicious (12.7) followed by Royal delicious (10.7) and
lowest (10.5) in Red delicious (Figure 2C). TSS of apples increased during storage. Highest TSS was noticed in
Golden delicious (14.6) followed by Royal delicious (14.3) and lowest (13.7) in Red delicious. TSS of apple is a
major quality parameter which is correlated with texture and composition. Increase in TSS could be attributed to
breakdown of starch into sugars or hydrolysis of cell wall polysaccharides (Weibel et al., 2004).
2.8 Titrable acidity (%)
At maturity stage, highest Titrable Acidity (TA) was recorded in Golden delicious (0.32%) followed by Red
delicious (0.24%) and lowest (0.23%) in Royal delicious (Figure 2D). The level of TA decreased during storage.
Highest acidity was recorded in Golden delicious (0.23%) followed by Red delicious (0.19%) while lowest in
Royal delicious (0.17%) after storage. Malic acid is the major acid in apple juice plays a major role in flavor
attribute (Ben et al., 1985). Reduction of TA during storage might be due to conversion of organic acid into
reducing sugars during ripening of fruit.
2.9 TSS: TA ratio
At maturity stage, highest TSS: TA ratio was recorded in Royal delicious (47.6%) followed by Red delicious
(43.8%) and lower (39.6%) in Golden delicious. The level of TSS: TA ratio increased after storage. Higher TSS:
TA ratio was recorded in Royal delicious (86.4) followed by Red delicious (73.8) while lower (63.6) in Golden
delicious (Figure 2E). This might be due to conversion of acid into sugars. Excessive increase in TSS: TA ratio in
Royal delicious caused imbalance resulting poor sensory rating due to development of slight bitterness and
mealiness. Mahajan (1994) reported that many biochemical changes take place during storage which disturbs the
TSS: TA ratio ultimately rendering the fruit unacceptable.
2.10 Starch index
At maturity stage, higher starch index was recorded in Royal delicious (4.9) followed by Red delicious (4.3) while
lower (3.9) in Golden delicious (Figure 2F). The level of starch decreased after storage. Higher starch index was
recorded in Royal delicious & Red delicious (6.0) while lower in Golden delicious (5.6). This might be due to
conversion of starch into reducing sugars during ripening of fruits. Saleh et al. (2009) reported that fruits stored at
90% RH and 0ºC for 6 months exhibited significant differences in physiological and anatomical parameters may
be due to ethylene production, responsible for the changes in texture, firmness and fruit softening.
3 Conclusions
Among the cultivars evaluated, Red delicious cultivar fruits had minimum level of damage during transportation,
less PWL, lesser spoilage, prolonged shelf life and higher sensory rating during storage which was followed by
Royal delicious. Besides having prolonged shelf life for Golden delicious fruits, they were less preferred by the
consumers as because of its poor physical appearance, sensitivity to damage during transportation and storage due
to thin peel and soft texture. For transportation of fruits from field to collection center in conical bamboo basket,
lining with grass or woolen shawl was found most efficacious, low cost and easily available lining materials to
reduce scratching damage.
References
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AOAC, 1990, Official Methods of Analysis, Association of Official Analytical Chemists, INC. USA
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Chaudhary B.N.Y.R., Pandey, Mahat B.B., and Yadav Y. P., 2004, Assessment of storage losses of apples under normal room condition of Jumla. In: Proceeding
of the Fourth National Workshop on Horticulture in Kathmandu, 2-4. March, 2004. Nepal Agricultural Research Council, NARI/HRD, Khumaltar, pp.
26-28.
Daillant-Spinnler B., MacFie H.J.H., Beyts P., and Hedderley D., 1996, Relationship between perceived sensory properties and major preference directions of
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