Physicochemical properties and in vitro digestibility of flours and starches from taro cultivated in different regions of Thailand

Abstract

This research aimed to study physicochemical properties and in vitro digestibility of flours and starches from taro cultivated in different regions of Thailand, that is, Kanchanaburi (KB), Chiang Mai (CM), Phetchaburi (PB) and Saraburi (SB). Taro starches were extracted from taro flours using either water or alkaline extraction. The taro flours had significantly (P ≤ 0.05) larger particle size, higher pasting and gelatinisation temperatures, and resistant starch content but lower total starch content, whiteness (L* value), paste viscosities and clarity than their corresponding extracted starches. All the taro starches exhibited polygonal and irregular granules and gave A-type X-ray diffraction pattern. The alkaline-extracted taro starches had significantly (P ≤ 0.05) higher extraction yield, total starch content, L* value, pasting and gelatinisation temperatures, and paste clarity but lower granular size, amylose content, resistant starch content, paste viscosities and relative crystallinity than their water-extracted counterparts.

Characterization and Technological Potential of Underutilized Ancestral Andean Crop Flours from Ecuador

“…These dimensions and appearance are similar to those reported by other authors in taro flours from Cuba (2.7 µm on average) [13] and Peru (0.3-10.0 µm) [51]. Wongsagonsup, et al [9] found much larger granule sizes in taro flours from Thailand, ranging from 52.17 to 67.63 µm, and indicated that this might be consequence of aggregated starch, because by isolating the starch, granule sizes ranged from 2.14-3.59 µm. At the bottom of the micrograph, other non-granular structures were clearly observed, which are attributed to other flour compounds.…”

“…Tarwi flour showed a marked lower starch content which was high compared with the value (1.3%) reported by Villacrés, et al [26] in debittered lupino. The starch content of taro in the present work was similar to that of taro from the Kanchannaburi (region of Thailand) and lower (59.8-72.62%) than that of some other varieties from several regions (Chiang Mai, Phetchaburi and Saraburi) in Thailand, attributing the drop in starch content to the decrease in average rainfall in the area [9]. The starch values in the present work are rather higher to those reported by Moorthy, et al [43] in fresh tubers of arracacha (20%) of taro (10-18%), camote (12-30%) and oca (12%) from Andean regions of Peru; these authors mentioned that the values could be associated with genotypic characteristics, climatic and environmental factors and the state of maturation.…”

“…There are several studies in the literature on these crops, not only from the Andean region, but also from other geographical areas. It is well known that their composition can vary due to factors inherent to the crop, and also greatly by the geographical distribution of the cultivars, as they are conditioned by climatic factors and the type of soil [7][8][9], sometimes giving rise to denominations of origin [10,11]. In the Andean region, differences of thousands of meters can be found within the higher areas ("altiplanos"), and even more so with those near sea level; therefore, the climatic conditions can be very different.…”

“…These flours may or may not have similar properties to traditional flours, so Andean crop flours can be an alternative option to substitute traditional flours in the industry, considering as well their possible different applications. Most studies have referred to tubers or grains, or their starch, such as arracacha flour from Brazil [7], taro flour from Cuba [13], starch and flour of Brazilian camote [14], flour of the Philippines camote [15], flour and starch of taro from Thailand varieties [9] and Tarwi flour from Egypt [16]. However, there are few studies on the characterization of flours of some of these crops from the Andean region.…”

Impact of Starch Modification Processes on Resistant Starch of Root and Tuber Crops

“…I. batatas starches were either C-or A-type starch. [21][22][23] These starch granules have also been found to be polygonal in shapes, with generally bigger sizes compared to edible aroids like C. esculenta and Xanthosoma spp.…”