Physicochemical Characterization of Mexican Cowpea (Vigna unguiculata) Tailing Starch

• Published in: Die Stärke 2006-01, Vol.58 (1), p.25-34
• Main Authors: Lecuona-Villanueva, Abril, Torruco-Uco, Juan, Chel-Guerrero, Luis, Betancur-Ancona, David
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cereal and baking product industries; Dietary fiber; Food industries; Functional properties; Fundamental and applied biological sciences. Psychology; Starch and starchy product industries; Tailing starch; Vigna unguiculata
• ISSN: 0038-9056; 1521-379X
• DOI: 10.1002/star.200500440

A physicochemical characterization was made of tailing starch isolated from cowpea (Vigna unguiculata), a legume. Proximate composition was 1.6% protein, 3.1% fiber, 0.7%, 0.6% ash and 94.0% carbohydrates as nitrogen‐free extract. Total dietary fiber content was 14.1%, soluble fiber was 12.1%, and insoluble fiber was 2.0% as determined by the Prosky method. Amylose content was 22.9%. Gelatinization temperature ranged from 73.5°C to 86.3°C, the peak temperature being 79.3°C. Gelatinization enthalpy was 12.9 J/g. Swelling power ranged from 6.1 g water per gram starch at 60°C to 26.3 g water per gram starch at 90°C. Solubility, analyzed within the same temperature interval, ranged from 4.3% to 23%. Water absorption capacity was 5.8 g water per gram starch at 60°C and 19.4 g water per gram starch at 90°C. Initial pasting temperature was 78°C, breakdown was ‐68 Brabender Units (BU), consistency was 265 BU, and setback was 197 BU. Clarity, expressed as transmittance, was 13.4%. Syneresis in a 6% gel stored for 24 h at 4°C was 6.6% and 22.5% at −10°C. The physicochemical properties of Mexican cowpea tailing starch indicate that it is a good source of dietary fiber which can be included in food systems that require thermal treatments as bakery products.