Physicochemical and Functional Properties of Tropical Tuber Starches: A Review
Prev Page | Next Page- Introduction
- Extraction Techniques
- Other components in Starch
- Colour and Appearance
- Granule Shape and Size
- Spectral Features
- X-Ray Diffraction Pattern
- Molecular Weight
- Amylose Content
- Thermal Characteristics
- Gelatinisation and Pasting Temperatures
- Viscosity
- Swelling Power
- Solubility
- Clarity
- Sol stability
- Digestibility
- Conclusions
1. Introduction
Tropical root and tuber crops are important food crops serving either as subsidiary or subsistence food in different parts of the tropical belt. They are rich sources of starch [1-4] besides many vitamins, minerals, etc. although there has been some decline in the use of these roots and tubers as food, their industrial application, especially that of cassava, is making rapid advantages. Cereals are the major source of commercial starches in most developed countries. Nevertheless, cassava (Manihot esculenta Crantz) and to a small extent, sweet potato (Ipomoea batatas Lam) are used for starch extraction in countries such as India, Brazil, Thailand, Indonesia, Philippines and China. Physical and chemical modifications of cereal starches are sometimes necessary to overcome certain undesirable characteristics and make them suitable for specific end uses. Though starch tailor-made for different applications can be made by various treatments, there has been a resistance towards use of modified starches in food applications since many chemicals are used for modification. Studies on different starches at Central Tuber Crops Research Institute (CTCRI) and elsewhere have brought to light the wide diversity in the starch characteristics of tuber crops and the possibility of using these native starches instead of chemically modified starches [5, 6]. In this treatise, the isolation and properties of tuber crop starches viz.., cassava (Manihot esculenta Crantz), sweet potato (Ipomoea batatas Lam), aroids (taro,, Colocasia esculenta; tannia, Xanthosoma sagittifolium and elephant foot yam, Amorphophallus paeoniifolius); yams (Dioscorea sp.) and minor tuber crops like arrowroot (Maranta arundinacea), yam bean (Pachyrrhizus erosus), Canna (Canna edulis), coleus or Chinese potato (solenostemon rotundifolius), Curcuma sp., etc. have been discussed, highlighting their advantages and potential uses.
