Microwave drying of ginger (Zingiber officinale Roscoe) and its effects on polyphenolic content and antioxidant activity.

Ismail, R. Kubra and Jagan Mohan Rao, L. (2012) Microwave drying of ginger (Zingiber officinale Roscoe) and its effects on polyphenolic content and antioxidant activity. International Journal of Food Science and Technology, 47. pp. 2311-2317.

PDF International Journal of Food Science and Technology 2012, 47, 2311–2317.pdf - Published Version Restricted to Registered users only Download (702kB)

Abstract

The effects of microwave (MW) drying on the total polyphenol content (TPP) and antioxidant properties of ginger extract (column extraction using 50% ethanol at room temperature) were evaluated using the Folin–Ciocalteau’s method, 2, 2′-diphenyl-1-picryl-hydrazyl assay, reducing power, antioxidant capacity and ferric reducing ability of plasma assay. The results were compared to that of the convective cross-flow drying (CD) at 50 ± 4 °C. Extract yield, TPP content (59–80 mg GAE per g) of the MW-dried samples increased with increase in MW power levels (PL 40, 60, 80 and 100), which might be as a result of MW energy causing breakdown of cellular constituents. The MW-dried (PL100, 800W) extract showed the highest quantity (1.5 fold) in TPP, [6]-gingerol content and antioxidant activity, when compared to the CD extract. Hence, it might be concluded that the optimal MW PL for drying of ginger slices with respect to retention of nonvolatiles such as TPP including [6]-gingerol was PL 100.

Item Type:	Article
Uncontrolled Keywords:	[6]-Gingerol, antioxidant, drying, ginger, microwave, polyphenols.
Subjects:	600 Technology > 08 Food technology > 30 Spices/Condiments 600 Technology > 08 Food technology > 32 Antioxidants 600 Technology > 08 Food technology > 06 Preservation and Storage > 02 Drying and Dehydration
Divisions:	Plantation Products Spices and Flavour Technology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	27 Nov 2012 05:04
Last Modified:	27 Nov 2012 05:04
URI:	http://ir.cftri.res.in/id/eprint/11052

Actions (login required)

View Item