Physico-chemical Properties and Digestibility of Pulse Starch after Four Different Treatments

Abstract

Soybean and peanut are pulses that are made up mainly of lipids, and most of these are edible oils. These pulses also contain a high level of protein. In contrast, Adzuki bean, kidney bean, and pea contain mainly starch, and they are utilized for salads, stews, and an (bean paste) products. Starchy pulses also are an excellent source of dietary fiber.1,2) Dietary fiber has been reported to have a protective effect in many adult diseases, such as arteriosclerosis, 3) hypertension, 4 7) large intestine cancer 8,9) and diabetes mellitus.10,11) Based on their structural features, three groups of dietary fibers can be identified: non starch polysaccharides and lignin, partially digestible starch and related chemical compounds, and other partially digestible materials.12 18) The dietary fiber content of starches increases upon heating, 1,2,19,20) a process thought to be due to the formation of resistant starch (RS). There appear to be several types of RS that differ in physico chemical properties.21 23) Fuwa et al . 24,25) reported that the RS level changes following heat moisture treatment of starch granules such as those found in high amylose corn starch. RS has been defined as the portion of starch in dietary fiber and related chemicals that is only partially hydrolyzed in the lumen of the small intestine.24 27) Heat moisture treatment of high amylose corn starch prevents its digestion in the small intestine. As a result, it passes into the large intestine where it can be utilized for short chain fatty acid production by enteric microbes. 28,29) Cooking is known to increase the dietary fiber content of dried pulses, but the reason for this has not been determined. In this study, we investigated this change in pulse fiber content by examining starch physico chemical qualities following four different treatments. MATERIALS AND METHODSPlant materials. Adzuki beans (Erimo var.), white kidney bean (tebou var.) and red kidney bean (kintoki var.) were harvested in the Tokachi region in 1997.Preparation of cooked beans. The three kinds of bean were left in water overnight. Each type of soaked bean was boiled in three times the volume of water for 1 h, resulting in the cooked beans. Beans were powdered by mill, after having been freeze dried.Preparation of starch. The protocols were performed essentially as described previously.30,31) The seed coat was removed by passing the ground dry pulse through a screen. Next, five volumes of 0.2% sodium hydroxide were added, and the mixture was agitated for 3 h. The mixture was then centrifuged at 3000 × !for 10 min, and the supernatant removed. This operation was repeated until protein was not detected in the supernatant. The dried precipitate was then washed until the pH was 7.0.Defatting of starch. The protocols were performed Abstract: In these studies, we found that the average starch particle size of Adzuki beans, and tebou var. and kintoki var. kidney beans was approximately 30 40 µm. In addition, these particles were globular with a Ctype crystal structure. Heating enhanced t...

Microstructures of starch granule, starch digestibilities and predicted glycaemic index of common bean mutants in Taiwan

“…These values were higher than the results of Kutoš et al. (2003) (91 mg g ‐1 seed dry weight) and Kojima et al. (2006) (less than 10 mg g ‐1 seed dry weight).…”

“…The resistant starch values for mutants ranged from 51.6 to 203.3 mg g -1 seed dry weight. These values were higher than the results of Kutosˇet al (2003) (91 mg g -1 seed dry weight) and Kojima et al (2006) (less than 10 mg g -1 seed dry weight). SA-11 was the only mutant that had considerably higher resistant starch content than wild type Hwachia (Table 1).…”

“…The measured starch granule sizes average from 17.92 (SA-31) to 27.00 lm (SA-03) in diameter (Table 1). The sizes of starch granules for the tested common beans were smaller than that in white kidney bean (31 lm) and red kidney bean (34 lm) (Kojima et al, 2006). Statistical analysis further showed that, across all the tested common Values are means ± SD, n = 3.…”

A comparison of functional properties of native Malawian cocoyam, sweetpotato and cassava starches

“…Swelling and solubility of the starches was determined in triplicates as follows: Dried starch samples (0.100 g) were mixed with 5 ml of distilled in 10 ml centrifuge tubes, heated for 1 h at 50, 70 or 90C while shaking every 5 min. The slurry was centrifuged for 30 min at 1500 × g, and the weight of the sediment in grams (B) determined (Kojima et al, 2006). The supernatant (A) was diluted with water until the total volume was 10 mL, and the amount of starch in it was determined by anthrone-sulphuric acid method (Brook et al, 1986).…”

Dietary Fiber Quantity and Particle Morphology of An (Bean Paste) Prepared from Starchy Pulses

“…1 3) The increase in dietary fiber caused by cooking has been attributed to both a property change of the pulse starch (to resistant starch, RS) and a strengthening of the starch granule. 1) RS resists the action of amylase 4 8) unless the RS is dissolved in an aqeous solution of 2 N potassium hydroxide. 9 12) RS has been classified into three types (RS1 RS3) based on its physicochemical properties.…”