Comparative Study of the Effect of Five Drying Methods on Bioactive Compounds, Antioxidant Potential and Organoleptic Properties of Zingiber officinale (Ginger) Rhizome
Yves M. T. Tientcheu
*
Centre for Food and Nutrition Research, Institute of Medical Research and Medicinal Plants Studies, P.O.Box 13 033, Yaoundé, Cameroon and Laboratory of Plant pathology, Department of Plant Biology and Physiology, Faculty of Sciences, University of Yaoundé 1, P.O.Box 812, Yaoundé, Cameroon.
Ruth E. K. Dibacto
Centre for Food and Nutrition Research, Institute of Medical Research and Medicinal Plants Studies, P.O.Box 13 033, Yaoundé, Cameroon and Laboratory of Nutrition and Nutritional Biochemistry, Department of Biochemistry, Faculty of Sciences, University of Yaoundé 1, P.O.Box 812, Yaoundé, Cameroon.
Ferdinand L. E. Edoun
Centre for Food and Nutrition Research, Institute of Medical Research and Medicinal Plants Studies, P.O.Box 13 033, Yaoundé, Cameroon and Laboratory of Nutrition and Nutritional Biochemistry, Department of Biochemistry, Faculty of Sciences, University of Yaoundé 1, P.O.Box 812, Yaoundé, Cameroon.
Elsa F. K. Matueno
Centre for Food and Nutrition Research, Institute of Medical Research and Medicinal Plants Studies, P.O.Box 13 033, Yaoundé, Cameroon.
Alex D. K. Tchuenchieu
Centre for Food and Nutrition Research, Institute of Medical Research and Medicinal Plants Studies, P.O.Box 13 033, Yaoundé, Cameroon.
Yadang Germaine
Centre for Food and Nutrition Research, Institute of Medical Research and Medicinal Plants Studies, P.O.Box 13 033, Yaoundé, Cameroon and Department of Food Science and Nutrition, National School of Agro-Industrial Sciences, University of Ngaoundéré, P.O.Box 455, Ngaoundéré, Cameroon.
Gabriel N. Medoua
Centre for Food and Nutrition Research, Institute of Medical Research and Medicinal Plants Studies, P.O.Box 13 033, Yaoundé, Cameroon.
*Author to whom correspondence should be addressed.
Abstract
Aims: Ginger (Zingiber officinale) is one of the most popular and widely used spice, known for its health benefits. This study aimed at assessing the potential impact of a Handcrafted dryer (HCD) on the quality of ginger in comparison to the most common drying methods.
Methodology: Fresh ginger originating from 2 regions were dried using the following techniques: HCD; Air Drying (AD); Ventilator Oven (VO) at 50°C, 60°C and 80°C; Freeze Drying (FD) and Microwave drying (MD) at 700 and 900 W) methods. Dried products were ground and infused in hot water and the total flavonoid contents, and antioxidant potential through different mechanisms (DPPH radical, FRAP and TAC assays) as well as the sensory properties of the infusions were assessed.
Results: TFC of the samples significantly varied with regard to the origin of the Ginger. Infusions deriving from the dried ginger from HCD and VO at 80°C exhibited the highest TPC, TFC and antioxidant activities. While the rise of temperature with VO led to an increase of TPC, it was rather a decrease that was observed with the rise of microwave power level but which did not have a significative effect on the antioxidant potential. No significant difference was noticed in the acceptance of infusions by consumers except MD samples, which received the lowest score by panelists.
Conclusion: Heat-based processes appears to be useful in the optimization of the nutritional value of dried ginger, and HCD appropriate for farmers as it is easy and not expensive to put into practice.
Keywords: Drying methods, ginger, bioactive compounds, antioxidant potential, organoleptic properties