International Journal of Agricultural Policy and Research Vol.1 (9), pp.227-235,November 2013
Available online at https://www.journalissues.org/journals/ijapr/
© 2013 Journal ISSN 2350-1561
Article 13/ID/ JPR81, 09 pages

Original Research Paper

Simple integrated solar drying -molecular sieve system for the beneficiation of rosella (Hisbiscus sabdariffa) plantation

Accepted 6 October, 2013

¹Hasibuan, R.,¹Trisakti, B.and ^*2Sundari, R

1Faculty of Chemical Engineering, University of  North Sumatera, Medan, Indonesia.
2The Body of Private Universities Coordination, Jakarta, Indonesia.

*Corresponding Author. E-mail: ritsun2003@yahoo.com
Tel. : +6285212483267

 Abstract

The study is encountered with rosella drying applying an own design of integrated solar drying – molecular sieve system using a drying chamber of 80 cm x 80 cm x 120 cm (768.103 cm3)  Optimum condition was found at 18.7 cm-distance between sample and fan with a rotation speed of 750 rpm.  The average correlation coefficient of falling drying curves at different rotation (500 rpm and 750 rpm) and at varied distances 18.7 cm, 34.7 cm and 50.7 cm was found to be 0.85 – 0.86.The avg. SD (n = 5) regarding the drying characteristics in terms of moisture content vs drying time was found to be 0.82% and the avg. efficiency of about 85% (n=5) based on 100 kg undried rosella. The substantial ingredients in the dried rosella with respect to protein and vitamin C were not seriously affected by this drying system. The reduction of ß-carotene in dried rosella until 50% of the initial ß-carotene in non dried rosella is suspected to be encountered with the conversion of ß-carotene to other fat and carbohydrate fragments due to warm air yielding an increase of fat content by a factor of about six and carbohydrate content by a factor of about fifteen found in the dried rosella product.  The  moisture content removal of  86-89 %  indicated a successful design of the integrated drying system that can be continued for the drying system of other agricultural products such as hazelnuts, guava, banana and apple in broader sense.

Key words: rosella; integrated solar drying – molecular sieve system; drying rate.