Effects of amadumbe starch nanocrystals on the physicochemical properties of starch biocomposite films

Agnes R Mukurumbira; John J Mellem; Eric O Amonsou

doi:10.1016/j.carbpol.2017.02.041

Effects of amadumbe starch nanocrystals on the physicochemical properties of starch biocomposite films

Carbohydr Polym. 2017 Jun 1:165:142-148. doi: 10.1016/j.carbpol.2017.02.041. Epub 2017 Feb 16.

Authors

Agnes R Mukurumbira¹, John J Mellem¹, Eric O Amonsou²

Affiliations

¹ Department of Biotechnology and Food Technology, Durban University of Technology, PO BOX 1344, Durban 4000, South Africa.
² Department of Biotechnology and Food Technology, Durban University of Technology, PO BOX 1344, Durban 4000, South Africa. Electronic address: eamonsou@dut.ac.za.

PMID: 28363534
DOI: 10.1016/j.carbpol.2017.02.041

Abstract

The influence of amadumbe starch nanocrystals (SNCs) at varying concentrations (2.5, 5 and 10%) on the physicochemical properties of biocomposite films prepared using two starch matrices, amadumbe and potato starches were investigated. Amadumbe SNCs exhibited square-like platelets morphology, typical of SNC derived from A-type starches. In general, the inclusion of SNCs significantly decreased water vapour permeability (WVP) of composite films whilst thermal stability and opacity were increased. Amadumbe starch films showed substantially high tensile strength (TS) compared to potato starch in the presence of SNCs. At 2.5% SNCs, TS of composite amadumbe film (8MPa) was about four times that of composite potato films. However, SNCs≥5% generally decreased TS of both potato and amadumbe films. Amadumbe SNCs can potentially be used as fillers to improve the properties of biodegradable starch films. Amadumbe starch has better film forming properties compared to potato starch.

Keywords: Amadumbe; Biocomposite films; Nanocrystals; Potato; Starch.