Starch digestibility and glycemic index of nine rice varieties in

Nigeria

Amaka M. Odenigbo; Michael Ngadi; Nehemiah Danbaba

Introduction

Average rice consumption per person in Nigeria : 21 kg (WARDA, 2004)

Higher glycemic response with rice compared to other starchy staples (Chan et al., 2001; Kumari and Sumathi, 2002).

Large variation of glycemic index (GI) for rice in different geographical location and very few data for Nigerian varieties (Foster-Powell et al., 2002; Brand-Miller et al., 1992)

Objective

To evaluate the predicted glycemic indices (pGI) and rate of in vitro starch digestion of 9 non-parboiled milled rice varieties grown

in Nigeria.

Samples

Rice varieties grown in Nigeria

Improved varieties Local varieties

• FARO 44• FARO52• FARO57• FARO60• FARO61

• Kwandala• Yardass• Jeep• Jamila

Starch Digestibility Protocol

Aliquots collected at intervals (30, 90, 120 min)

Pepsin/Pancreatic amylase/amyloglucosidase

Enzymatic digestion

pGI

Kinetics of starch hydrolysis

Only 90 min aliquots

Starch hydrolysis curves for non-parboiled improved rice varieties (0-120 min)

Starch hydrolysis curves for non-parboiled local rice varieties (0-120 min)

CONCLUSION• Rates of starch digestibility varied among local and

improved milled rice varieties. • The local rice varieties had significantly lower

levels of pGI and rate of starch hydrolysis.• Non-parboiled rice varieties should not be

generally regarded as high GI food. • This data provides insights on the selection of local

varieties for breeding newly improved rice.

Thank You!Merci!