Starch content

Stftrke-gehalt, m. starch content. >grad, m. de gree of strength, intensity, -gummi, n. starch gum, dextrin. 

The tenderometer is not readily adaptable for measurement of maturity in the finished product, and any method used for estimating maturity at this point should yield results well correlated with those obtained by the tenderometer. Estimation of total solids or starch content appears to fulfill this requirement very well. 

Starch content was determined using the enzyme-kit of Boehringer/Mannheim. 

Fig. 17 Effect of starch content of granules on dissolution rate of salicylic acid contained in compressed tablets. Q, 5% . 10% x, 20% starch in granules. (From Ref. 22.).

Fruits and vegetables Potato, carrot Edible, proteins stable in storage tissues Must be cooked before consumption (potato), high starch content (potato)... 

Starch content of field peas (Pisum sativum L., cv. Trapper) ranges from 43.7 to 48% and, after being subjected to pin milling and air classification, produces a flour containing 78% starch (9,12,13). 

As seed moisture in field peas decreases, there is a decrease in starch fraction yield, protein content of starch fraction, protein content of protein fraction, and percent starch separation efficiency, and a concurrent increase in protein fraction yield, percent starch in starch fraction, percent starch in protein fraction, percent protein separation efficiency, and percent neutral detergent fiber in the protein fraction. Lower moisture content of field peas improves milling efficiency and results in more complete separation of protein and starch fractions, which could explain the increase in protein fraction yield and percent starch in starch fraction, improved protein separation efficiency and less protein in the starch fraction. The decrease in starch separation efficiency was probably due to the increased starch content of protein fraction and increased protein fraction yield with lower seed moisture. 

Analytical Methods. The samples were analyzed by standard AACC (21) procedures for moisture (air-oven method), protein (Method 46-13), crude fat (Method 30-25), crude fiber (Method 32-10), insoluble dietary fiber (Method 32-20) and ash (600°C, 3 hr). Starch content was determined by the polarimeter method (Method 76-20) and total sugars by Method 80-60. Color characteristics of the dried products were evaluated with the Hunter Color Difference Meter. 

A summary of the proximate analyses of these yam tubers is shown in Table 1. On a fresh weight basis, protein is quite low because of the high water and starch contents of yams (dry weight protein content is 4-8%). Yams are rarely consumed alone but,... 

According to filler theory, connectivity can be achieved at lower values when the filler form is plates rather than spheres. Depending on the proportions of the plates and whether or not an inactive phase is included in the blend, connectivity can be achieved at 8 to 16% (v/v) filler (4). The starch-plastic blends developed by Otey (2) have a laminate structure when the starch content is under 30% by volume (Figure 1) and the threshold for microbial attack on these materials is under 13% starch by volume (Figure 2). This low threshold value can be explained by considering the LDPE as a non-conductive (enzyme-impermeable) phase combined with a conductive phase of starch-EAA complex. 

Porosity characteristics also influence the degradation rate of blends containing intact starch grains. Amylase removal of starch from these films was not highly correlated with starch content, since films whose starch content was above possible "percolation thresholds" (6) were degraded at very different rates when starch content was not very different (Table I). 

Starch, a reserve polysaccharide widely distributed in plants, is the most important carbohydrate in the human diet. In plants, starch is present in the chloroplasts in leaves, as well as in fruits, seeds, and tubers. The starch content is especially high in cereal grains (up to 75% of the dry weight), potato tubers (approximately 65%), and in other plant storage organs. 

Decrease adverse Gl effects by reducing dietary starch content... 

Wehmeyer et al. (1969), Bower et al. (1988), and Amarteifio and Moholo (1998) reported the content of carbohydrate to be 23%, 24%, and 19%, respectively. These values have been obtained indirectly as the difference between 100% and the content of proteins, lipids, and minerals. Holse et al. (2010) found that the content of carbohydrate was dominated by total dietary fiber as it varied between 18.7% and 26.8% dm (Table 5.2). The majority of the dietary fiber is insoluble as only about 4% of the dietary fibers are soluble. Comparing the content of total dietary fiber of morama bean with the content of peanut (9% dm) and soybean (10% dm) (U.S. Department of Agriculture, 2007), it appears that the morama bean has a considerably higher level of indigestible carbohydrates. Holse et al. (2010) also reported a very low starch content, which is in contrast to other legumes, in which starch is usually the most abundant carbohydrate... 

The phenotype of a potato plant is very plastic (environmentally variable) with regard to many traits of interest for potato breeders. The effect of production environment on traits such as yield, tuber number, tuber size, specific gravity, and processing quality presents a challenge that is difficult to overcome. It requires the testing of clones in multiple years and locations. For example, quantitative trait loci have been detected for tuber starch content, but few were stable across environments (Schafer-Pregl et al., 1998). Similarly, environment has a laige impact on... 

Schafer-Pregl, R., Ritter, E., Concilio, L., Hesselbach, J., Lovatti, L., Walkemeier, B., Thelen, Ft., Salamini, F., Gebhardt, C. (1998). Analysis of quantitative trait loci (QTLs) and quantitative trait alleles (QTAs) for potato tuber yield and starch content. Theoretical and Applied Genetics, 97, 834-846. 

Micronutrients do also affect potato quality and yield applications of B, Mn, and Zn increase the starch grain size, while applications of iodine or ammonium molybdate increase the dry matter and starch content. 

Komiyama, S., Kato, J., Honda, H., Matsushima, K. (2007). Development of sorting system based on potato starch content using visible and near-infrared spectroscopy. J. Japan Soc. Food Sci. TechnoL, 54, 304-309. 

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