Thermal properties of cowpea flour: A study by differential scanning calorimetry

✍ Scribed by Henshaw, Folake O. ;McWatters, Kay H. ;Akingbala, John O. ;Chinnan, Manjeet S.

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 238 KB
• Volume: 47
• Category: Article
• ISSN: 0027-769X
• DOI: 10.1002/food.200390038

✦ Synopsis

Abstract

The thermal properties of 12 varieties of cowpea flour were studied by differential scanning calorimetry (DSC). Flour samples were prepared to a paste of 60% moisture content and sealed in standard DSC pans. Samples were scanned at a heating rate of 5°C/min over a scan range of 40–130°C. Samples exhibited single major endotherms, which occurred over varied temperatures. The transition enthalpy (Δ__H__) ranged between 1.4 J/g and 4.7 J/g. Transition onset (T~o~) and transition peak (T~p~) temperatures ranged between 75–78°C and 78–82°C, respectively. All the DSC parameters measured varied significantly among the varieties. The transition enthalpy (Δ__H__) was the most discriminating parameter and accounted for 80% of the total variance. The major chemical components of cowpea flour, starch amylose and protein are significant predictors of Δ__H__. Protein denaturation appears to be a significant modification which occurs during processing of cowpea seeds to flour. The transition enthalpy Δ__H__ could become an important functional index of cowpea flour when related to some quality parameters in products that contain the flour.