Bhutan Journal of Natural Resources and Development

College of Natural Resources

Effect of Blanching Duration and Drying Methods on the Proximate Composition of Green Chillies (Capsicum annuum L.)

Gurung, Tulsi.;  Wangchuk, Karma .;  Sitaula , Bishal .K; 



Farmers in Bhutan practice hot water blanching and sun drying of green chillies as one of the preservation measures. The blanched dried chilli is known as ema shukam locally and is used in preparing various traditional cuisines. Blanching is done for 2-3 minutes by immersing in boiling water and drying in open sun. However, blanching and drying process lead to quality changes such as texture, colour, flavour, and nutritional value. Therefore, this study aimed to determine the proximate compositions of sun dried and oven dried green-blanched chillies. An experiment with two drying methods and two levels of blanching durations with three replications for each treatment were conducted to examine the proximate compositions of the dried and blanched chillies. Blanching duration of two minutes retained higher carbohydrates ( = 31.78) than three minutes (= 26.08). However, the Mann-Whitney U test showed no significant effect of blanching duration on carbohydrate (U = 7.5, z = -.690, p < .05). Drying methods had significant effect only on fat content with oven drying retaining higher fat content (= 4) compared to sun drying method (= 2); (U = 2, z = -2.713, p < .01). Blanching for three minutes resulted in higher loss of Vitamin C content. The colour of oven dried chilli was dark brownish green even at low temperature of 37 oC. Hot water blanching of green chillies for two minutes followed by sun drying produced desired colour on dried chillies.


Blanch, chilli, oven drying, nutrient, sun drying

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