Journal of Food, Agriculture and Environment




Vol 12, Issue 2,2014
Online ISSN: 1459-0263
Print ISSN: 1459-0255


Electric field enhancement of macadamia drying


Author(s):

Tuangsap Jongjaipak, Songchai Wiriyaumpaiwong *, Juckamas Laohavanich

Recieved Date: 12014-01-30, Accepted Date: 2014-03-24

Abstract:

Macadamia nut has high nutritional values leading to a high consumer demand. However, moisture reduction after harvest is still a problem. Conventional hot air drying has high energy consumption and long drying time. Prolonged exposure to oxygen and heat results in quality deterioration. The effects of hot air temperature and electric field intensity on the drying characteristic and quality were studied. The variations of hot air temperature and electric field intensity were ranging in 40-60°C and 50-150 kV/m. Drying air velocity was fixed at 1.0 m/s. Macadamia nuts in shell were dried from a moisture content of 28-30% dry basis down to 4-5% dry basis. The dry samples were analysed for colour and peroxide value. Energy consumption was also measured. The results showed that both high temperature and high electric field intensity dry the nuts faster. The macadamia nut colour after drying at 40, 50 and 60°C was significantly different (p≤0.05). High drying temperature results in lower brightness (L*) while redness (a*), yellowness (b*) and total colour difference (∆E) are higher. Increasing electric field intensity leads to lower brightness. Drying at higher temperature results in higher peroxide value, but peroxide value is decreased by applying the electric field. Overall, the higher drying temperature and electric filed intensity lead to a higher drying rate. The combination of hot air and electric field also leads to lower specific energy consumption.

Keywords:

Macadamia, colour, electric field, peroxide value, specific energy consumption


Journal: Journal of Food, Agriculture and Environment
Year: 2014
Volume: 12
Issue: 2
Category: Food and Health
Pages: 114-117


View full PDF
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 :