Starch is composed of amylose and amylopectin and deposited as granules of different sizes and shapes with semi-crystalline and amorphous concentric layers that show the ‘maltese cross’. Starches f...

https://tandfonline.com/doi/pdf/10.1080/19476337.2018.1518343

The structural characteristics of starches and their functional properties

Cassava (Manihot esculenta Crantz) is one of the most important sources of starch in the tropics. There is limited and contradictory information regarding cassava starch characteristics. The International Center for Tropical Agriculture (CIAT) holds in trust FAO's cassava germplasm collection. Starches from 3272 landraces (including 12 wild relatives) and 772 improved clones were extracted and analyzed over a period of several years. In most cases only one starch sample per genotype was analyzed. Average cyanogenic potential was 327 ppm but considerably higher in the landraces (340 ppm) than in improved clones (267 ppm). Average total and reducing sugars were slightly higher in improved clones (4.06 and 1.56%, respectively) than in landraces (3.68 and 1.25%, respectively). Amylose content was similar in both types of germplasm with an average of 20.7%. Average pasting temperature was 65.3°C. Maximum viscosity was 777.5 mPa s, breakdown was 298.1 mPa s, consistency was 155.8 mPa s and setback was -144.5 mPa s. The large sample of starches analyzed provides very robust information regarding the actual characteristics of cassava starch. (Resume d'auteur)

Screening of Starch Quality Traits in Cassava (Manihot esculenta Crantz)

On the importance of organization of glucan chains on thermal properties of starch.

Using xylenol orange as indicator, the PO 4 3 in solution was determined by direct titration of bismuth nitrate standard solution.This method has been used to determine the phosphorus in phosphorus ore.

Determination of Phosphorus in Phosphorus Ore

Interests in sweetpotato production and utilization are surging in recent years. The major carbohydrate of sweetpotato root is starch which accounts up to around 80% of the dry matter, with a large and cheap potential supply. This review summarizes the recent advances in physicochemical properties, structure, modifications, and uses of sweetpotato starches, and provides suggestions for further research to improve the utilization.

Physicochemical properties, molecular structure, and uses of sweetpotato starch

Starches from six different species (cassava, arrowroot, sweet potato, yam, canna and ginger) were isolated and some structural and physicochemical characteristics analysed and correlated. Phosphorous and amylose contents were determined using a colorimetric method and measuring iodine affinity, respectively. Molecular weight distributions of starches were analysed by Sepharose CL 2B. Granular shape and size distribution were performed using an image analyser system attached to a light microscope. Swelling power was determined at 60, 70, 80 and 90°C. Pasting and thermal properties were measured using a rapid viscoanalyser, and a differential scanning calorimeter, respectively. Phosphorous content varied from 0.007 to 0.031% for cassava and canna starches, respectively. Yam, canna and ginger starches displayed higher amylose contents (32.6, 31.7 and 26.5%, respectively) than cassava, arrowroot and sweet potato starches (19.8, 20.8 and 22.6%, respectively). These last three starches displayed amylose molecu...

F. H.G. Peroni

Papers

Some structural and physicochemical characteristics of tuber and root starches