| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 55.39 KB | Adobe PDF |
Advisor(s)
Abstract(s)
The present study evaluates the effects of drying on apple slices from two varieties, Golden
Delicious and Granny Smith, which were analyzed in terms of physical and chemical
properties. The tests involved the determination of moisture, acidity, soluble solids, colour
and texture. Trials were performed in a convective hot air dryer for different temperatures of
30, 40, 50 and 60 ° C.
The results showed that the final moisture of the two varieties of apples was around 3 % (wet
basis). With regards to acidity, the variety Granny Smith was found to be more acid than the
Golden Delicious. The soluble solids are present, in general, in greater amounts in the
variety Granny Smith. As to the colour, this varied very considerably from the fresh apples to
the dried ones. Apples of the variety Golden Delicious presented a higher intensity of yellow
(b* > 0) and red (a* > 0). However, in comparison to the variety Granny Smith the Golden
Delicious presents, in general, smaller total colour differences. The textural attributes
evaluated were hardness, adhesiveness, elasticity, cohesiveness and chewiness. However,
the results for adhesiveness were very close to zero showing that these products do not
have adhesiveness, as it happens with other fruits. It was also found that the fresh apples
have a much higher hardness, when compared to the dried samples. Elasticity, on the other
hand, was kept approximately constant regardless of the variety or state. Cohesiveness was
higher in the fresh apples, and for the dried ones was higher for variety Golden. Finally,
chewiness was higher for the fresh apples in comparison to the dried ones, and was higher
for Golden Delicious when compared with Granny Smith.
Description
Keywords
apples drying acidity colour texture
Citation
Cruz AC, Guiné RPF, Gonçalves JC, Correia AC. (2012) Study of chemical and physical properties of apples dried in a convective drier. Proceedings (Electronic) da International Conference of Agricultural Engineering CIGR-AgEng2012, 6 pp.