Slide 1

Hii, Law - Quality Evolution During Drying of FVFs

physical
attributes

cles (15-30%) and thickness (60-75%) (2006)

Chicken
meat

Shrinkage at 50-71% and less shrinkage

in superheated steam – heat pump drying

Nathakaranakule et al.

(2007)

Apple slices Microwave and infrared drying showed
11 - 12% lower shrinkage, 30-34% lower
volume, 18-23% lower density and poros-
ity 25-28% higher than the convection
method

Witrowa-Rajchert and

Rząca (2009)

Rehydration Vegetables Temperature increment increases the
rehydration capacity. Rehydration ratio
ranges between 1 to 4 for all the ex-
amined materials

Krokida and Marinos-

Kouris (2003)

Texture Chempedak Hardness, cohesiveness and chewiness
increased with temperatures. Springiness
decreased

Chong et al. (2008)

Colour Chempedak L and b decreased but a* increased with
temperature

Chong et al. (2008)

Sensory Banana Banana dried at 60°C were better ac-
cepted due to softer texture and better
colour

Leite et al. (2007)

Nutritional Various
fruits and
vegetables

Freeze drying preserved the highest re-

tention of vitamins. Low oxygen level re-

duced loss of nutrients. Pretreatment im-

proved nutrients retention

Sablani (2006)

Figs Pretreatments caused micro wounds on
fruit peel and enhanced water removal

Piga et al. (2004)

Banana and
Guava

Step-down drying reduced colour degra-

dation without compromising on drying

time

Chua et al. (2002)

Vegetables Retention of vitamin C and total caroteno-
ids were better under inert drying envi-
ronment.

Ramesh et al. (1999)

Sweet pota-
toes

Steamed freeze dried purple-fleshed

sweet potatoes showed 40% higher ORAC

antioxidant activity than fresh freeze

dried powder and 20% higher than steam

air-dried powder

Yang and Gadi (2008)