Abstract
Cassava, cocoyam and sweetpotato constitute underexploited but yet important sources of starch for the Malawi industry. The functional properties of starches isolated from cassava, cocoyam and sweetpotato were studied and compared. Results revealed diverse functional properties among the starches from the different sources. With increasing temperature, water binding capacity, swelling power and solubility of the starches increased. Cocoyam and sweetpotato starches exhibited lower water binding capacity and swelling power, paste clarity and viscosity but higher degree of syneresis than cassava starches. Solubility was higher in cocoyam starches than sweetpotato and cassava starches. Cocoyam starches had higher gelatinization temperatures than sweet potato and cassava starches but similar transition enthalpies with cassava. Retrogradation studies by differential scanning calorimetry and turbidometry revealed higher levels of retrogradation for cocoyam and sweetpotato starches compared to cassava starches. Thus starches from sweetpotato, cocoyam and cassava would play different roles in various industrial applications. Key words: Sweetpotato, cocoyam, cassava, starch, functional properties.
Highlights
Starch is widely used in different applications in the food and non-food industries
Cassava starches are better suited for the food industry as gelling agents than cocoyam and sweetpotato starches (Gbadamosi et al, 2013)
They could be used in frozen food products as stabilisers and emulsifiers as starches with high Water binding capacity (WBC) usually bind more water preventing syneresis (Otegbayo et al, 2013)
Summary
Starch is widely used in different applications in the food and non-food industries. Its application is primarily determined by its functional properties which vary with botanical source (Wickramasinghe et al, 2009; Nwokocha et al, 2009; Yuan et al, 2007; Amani et al, 2004). The demand for starch in industries worldwide is currently being met by a restricted number of crops mainly corn, potato and wheat. Tropical root and tuber crops of which sweetpotato (Ipomoea batatas), cocoyam (Colocasia esculenta) and cassava (Manihot esculenta) are important representatives, remain underexploited sources of starch for the industry worldwide despite being rich in starch (Ellis et al, 1998). In Malawi, these three crops are grown mainly as subsistence crops limiting their potential contribution to the starch-based industries. There is need for unveiling the characteristic properties of
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call