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Metabolomic Analysis of Barley by Gas Chromatography/Mass Spectrometry
Published on: November 8, 2024
Barley cultivar, kernel composition, and processing affect the glycemic index.
Ahmed Aldughpassi1, El-Sayed M Abdel-Aal, Thomas M S Wolever
1Department of Nutritional Sciences, University of Toronto, Toronto, Canada.
The Journal of Nutrition
|July 27, 2012
Summary
Barley
Area of Science:
- Agricultural Science
- Nutritional Science
- Food Science
Background:
- Barley is recognized for its low glycemic index (GI).
- The impact of barley's carbohydrate composition, processing, and food form on its GI remains unclear.
- Understanding these factors is crucial for optimizing barley's health benefits.
Purpose of the Study:
- To investigate how barley cultivar variations (amylose, beta-glucan content) affect GI.
- To determine the influence of food processing (pearling) and food form (pasta) on barley GI.
- To explore the relationship between GI and barley's starch characteristics and fiber content.
Main Methods:
- Three experiments involving 9 barley cultivars and 30 healthy participants.
- Cultivars were subjected to different processing levels: whole-grain (WG) and white pearled (WP).
- Glycemic index was measured, and correlations with fiber and starch characteristics were analyzed.
Main Results:
- GI varied significantly by barley cultivar and pearling, with WG having a lower GI than WP.
- GI ranged from 21 to 36 for different whole-grain cultivars.
- Pasta form altered GI, with whole-grain pasta showing a higher GI than white pearled pasta in one experiment.
- GI was inversely correlated with total fiber content (r = -0.75, P = 0.002).
- Starch characteristics did not predict barley GI.
Conclusions:
- Barley's glycemic index is significantly influenced by cultivar, processing methods, and final food form.
- Total fiber content is a key factor in determining barley's GI.
- Starch composition, including amylose content, does not reliably predict barley's glycemic response.
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