Journal of Food, Agriculture and Environment




Vol 10, Issue 2,2012
Online ISSN: 1459-0263
Print ISSN: 1459-0255


Optimization of hot-air drying conditions on the physicochemical characteristics of torch ginger (Etlingera elatior)


Author(s):

N. H. Juhari 1, O. Lasekan 2*, M. Kharidah 3, S. Ab Karim 1

Recieved Date: 2012-01-12, Accepted Date: 2012-04-30

Abstract:

Response surface methodology (RSM) was used to determine the effect of hot-air drying on physicochemical characteristics of torch ginger (Etlingera elatior). Three independent variables were time (3-5 hours), temperature (40-80°C) and loading capacity (0.5-2 kg/m2). In this research, 20 treatments were assigned based on central composite design (CCD) containing 8 factorial points, 6 centre points and 6 axial points. The quality of dried Torch ginger produced was evaluated by determining moisture content, water activity, Hunter L, a, b values and texture (brittleness). The results revealed that the linear terms exhibited significant (P<0.05) effect on moisture content. The quadratic terms showed significant (P<0.05) effect on water activity, texture (brittleness), colour L and colour b values; while for colour a values, the interaction terms of drying condition was the most significant (P<0.05) factor. A satisfactory coefficient of determination (R2) at 0.523, 0.807 and 0.953 was obtained for the response variables studied namely texture, moisture content and water activity, respectively. However, there are an unsatisfactory coefficient of determination (R2) for colour- L, colour-a and colour-b. No significant (p>0.05) lack of fit was indicated for the reduced models, except for the models fitted for texture. The optimization results indicated that the best response, within the range studied, was reached when the drying time was 4.1 h, the drying temperature 79°C and loading capacity 0.7kg/m2, respectively. No significant (p>0.05) difference was found between the experimental and predicted values, thus ensuring the adequacy of the response surface models employed for describing the effects of hot-air drying on physicochemical properties of Torch ginger.

Keywords:

Torch ginger, hot-air drying, physicochemical properties, Etlingera elatior, response surface methodology, optimization, herb and spices, drying, central composite design, ginger flower


Journal: Journal of Food, Agriculture and Environment
Year: 2012
Volume: 10
Issue: 2
Category: Food and Health
Pages: 64-72


Full text for Subscribers
Information:

Note to users

The requested document is freely available only to subscribers/registered users with an online subscription to the Journal of Food, Agriculture & Environment. If you have set up a personal subscription to this title please enter your user name and password. All abstracts are available for free.

Article purchasing

If you like to purchase this specific document such as article, review or this journal issue, contact us. Specify the title of the article or review, issue, number, volume and date of the publication. Software and compilation, Science & Technology, all rights reserved. Your use of this website details or service is governed by terms of use. Authors are invited to check from time to time news or information.


Purchase this Article:   20 Purchase PDF Order Reprints for 15

Share this article :