Yams.

This chapter discusses the extraction of starch from different yam (Dioscorea) species. The physiochemical (biochemical property, amylose and amylopectin content), structural (granular morphology, X-ray diffraction pattern, starch crystallinity, and amylose and amylopectin structure), functional (swelling pattern, solubility, viscosity, rheological properties and retrogradation) and thermal properties of yam starches and their digestibility are described.

Sweet potato.

This book chapter outlines the extraction and purification, physiochemical properties (i.e. biochemical characteristics, amylose and amylopectin content), structural properties (i.e. granule morphology, XRD and starch crystallinity, structure of amylose and amylopectin), functional properties (i.e. swelling pattern and solubility, viscosity, rheological property, retrogradation), thermal properties (i.e. DSC), and digestibility of sweet potatoes.

Other starches.

This chapter discusses the extraction, physiochemical (chemical composition, amylose and amylopectin content), structural (granular morphology, X-ray diffraction pattern, starch crystallinity, and amylose and amylopectin structure), functional (swelling pattern, solubility, viscosity, rheological properties and retrogradation) and thermal properties, and digestibility of starches from minor tuber crops (e.g., arrowroot, Curcuma spp., Canna edulis [C. indica], Chinese water chestnut [Eleocharis dulcis], chayote [Sechium edule], Pachyrhizus ahipa, Oxalis tuberosa, Arracacia xanthorrhiza, Lilium spp.).

Aroids.

This book chapter outlines the extraction and purification, physiochemical composition (i.e. biochemical content, amylose and amylopectin content), structural properties (i.e. granular morphology, XRD and starch crystallinity, amylose and amylopectin structure), functional properties (i.e. swelling and solubility, viscosity, rheological properties, retrogradation), thermal properties (i.e. DSC, digestibility) of aroids.

Cassava.

This book chapter outlines the extraction and purification (i.e. determination of starch in roots, water requirements, industrial-grade tapioca starch manufacture, semi-mechanized tapioca starch manufacture, modern methods of tapioca starch manufacture), physiochemical properties (i.e. biochemical content, amylose and amylopectin content), structural properties (i.e. granular morphology, XRD and starch crystallinity, structure of amylose and amylopectin), functional properties (i.e. swelling pattern and solubility, viscosity, rheological properties, retrogradation, thermal properties, DSC, and digestibility) of cassava.

Formation Characteristics of Endosperm Structures in Different Rice Genotypes

To explore the formation characteristics of endosperm structures in different rice genotypes, indica, japonica and glutinous rice cultivars were used and grown in the paddy field. The endosperm structures in the grain during the filling period were investigated. The results showed that the compactness of amyloplast arrangement was positively correlated with grain filling percentage. The endosperm structure varied with the position within a grain. At maturity, the structure was the best in the back, the intermediate in the center, and the worst in the belly of a kernel. However, the filling was better in the center than in the back and in the belly from 5 to 10 days after flowering (DAF). The endosperm structure was different among genotypes. From 5 to 25 DAF, starch accumulation was the earliest in glutinous rice, followed by indica rice and japonica rice. Gaps and pores in endosperm were closely associated with rice transparency. The starch crystallinity in endosperm was negatively correlated with amylose content. Among the three genotypes, glutinous showed the highest crystallinity, followed by japonica and indica rice. The starch crystallinity in a grain was lower on a primary branch than that on a secondary branch. Among all grains, the second grain on a primary branch showed the lowest starch crystallinity. The results indicated that the starch structure of endosperm not only differ between rice genotypes, but also varies with the location of a grain on the panicle, and that it affects the grain-filling, transparency and amylose content of rice.

Quality characteristics of snacks produced from nixtamalized corn flours of new drought-tolerant yellow corn hybrids

Introduction. Producing new maize cultivars in areas with limited water resources is the main task of plant breeders. However, there is little information regarding their technological characteristics and industrial potential. Besides, snacks have gained worldwide acceptability and become part of modern food culture, especially among young people and children. Thus, our study aimed to produce corn snacks from new yellow corn hybrids planted under water stress in Delta region, Egypt. Study objects and methods. We investigated healthy processing techniques and used nixtamalization and baking instead of frying. We also evaluated the chemical composition and starch crystallinity of flour, the rheological properties of dough, as well as color attributes and sensory characteristics of baked snacks. Results and discussion. Significant differences (P ˂ 0.05) were found between all corn genotypes in their fat, protein, ash, crude fiber, and carbohydrate contents. The experimental drought conditions caused higher protein and fat contents compared to normal conditions. X-ray diffraction indicated that nixtamalization decreased starch crystallinity. Also, X-ray and rapid visco analysis showed that Y2 genotype exhibited the highest crystallinity and the lowest pasting properties, while Y3 and Y5 had the lowest crystallinity and the highest pasting properties. Baked snacks made from nixtamalized corn flour of genotypes planted under drought conditions had comparable quality characteristics in terms of color and sensory properties to the control snacks made from SC178 genotype planted under normal conditions. Conclusion. The new corn hybrids grown in limited water conditions and the developed snacks represent a healthy alternative to cornbased fried snacks.