1. Food Safety Research Centre (FOSREC), Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
2. Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
3. Corresponding author. Phone: +60 38946 8393. Fax: +60 38942 3552. E-mail: jinap@upm.edu.my; sjinap@gmail.com