Processing Of Some Tubers and the Effect on the Carbohydrate Digestion, Functional Groups and the Morphology of the Extracted Starches
Aletor, Oluwatoyin and Ogunrinde,
Correspondence Address :
of chemistry the Federal University of Technology,
Ondo State. Nigeria
Received on: February 22, 2019, Accepted on: March 18, 2019, Published on: March 25, 2019
Citation: Aletor, Oluwatoyin and Ogunrinde, Faith Oreoluwa (2019). Processing Of Some Tubers and the Effect on the Carbohydrate Digestion, Functional Groups and the Morphology of the Extracted Starches.
Copyright: 2019 Aletor Oluwatoyin et.al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Three different tubers namely white yam (Dioscorea rotundata), sweet potato (Ipomoea batatas) and cocoyam (Colocasia esculenta) were processed (roasted and boiled), the raw served as the control and all samples were characterised with respect to their proximate composition, anti-nutrients and phytochemical contents, sugars and functional groups.
Thereafter, starches were extracted from them and analysed for sugars (after digestion with α amylase enzyme) also, the structural morphology of the extracted starch granules were examined using scanning electron microscope .Results on proximate composition were significantly different p≥0.05, protein content was decreased in all the boiled and roasted samples while the ash content increased in all roasted tubers. Data on antinutrients and phytochemical revealed that tannin, saponin, terpenoid, oxalate and phytate were in the ranges (mg/g) 0.52-1.70; 17.36-169.27; 1.31-5.00, 0.18-1.16 and 6.59-22.25 respectively. Flavonoid was absent in the cocoyam while phlobatannin and alkaloid were below detection limit in sweet potato. Results on functional groups before and after starch extraction showed the presence of OH, C2H2n, CnH2n-2, RX and ROR. Scanning electron microscopy on the starch granules showed an increase in the surface area in the boiled samples. Complex carbohydrate digestion before and after addition of the enzyme revealed digestion were highest in all roasted samples. Processing generally had effects on the nutritive characteristics of all the tubers analysed.
Tubers, Boiled, Roasted, Starch digestion, Functional Groups, Morphology