Effects of microwave-discharged cold plasma on synthesis and characteristics of citrate derivatives of corn starch granules

Abstract

The objectives of this study were to identify the potential function of microwave-discharged cold plasma (MCP) treatment in preparing starch citrate (SC) non-thermally and to investigate the physicochemical properties of MCP-induced starch citrates. SCs were prepared by either dry heating in a convection oven (as a reaction control; COV) or MCP treatment using N (N-MCP) and N-O (N/O-MCP). Fourier transform-infrared spectra of the MCP-induced SCs revealed new peaks indicating ester bonds. The molar degree of substation was 0.013-0.015 depending on the reaction conditions. The plasma-formed dents were observed more on the surfaces of granular starch citrates (GSCs) treated with N/O-MCP than N-MCP. Relative to COV, MCP-induced GSCs possessed lower resistant starch content, solubility, and gelatinization temperatures and higher swelling power. The pasting viscosities were higher with N-MCP GSCs and lower with N/O-MCP GSCs. The results suggest that MCP can be used as a novel catalyst for non-thermal starch citration.

Effect of the Esterification of Starch with a Mixture of Carboxylic Acids from Yarrowia lipolitica Fermentation Broth on Its Selected Properties

“…This may indicate that increasing the citric acid dose would increase the DS only to a certain value, while successive increase in its dose would not increase the amount of starch citrate produced. A higher DS can, probably, be obtained by using other esterification methods [ 5 , 31 , 32 ].…”

Production and Properties of Starch Citrates—Current Research

“…In recent studies, processes of esterification/crosslinking with citric acid have been conducted with various starch types, including both these produced on the large industrial scale, i.e., “normal” and waxy maize starch [ 27 , 31 , 32 , 33 , 34 , 35 , 36 ], wheat starch and its A and B fractions [ 22 , 37 ], potato starch [ 38 , 39 , 40 , 41 , 42 , 43 ], rice starch [ 44 , 45 ], and cassava starch [ 14 , 43 , 46 , 47 ], as well as with starch extracted from local plants, i.e., from banana [ 43 , 48 ], taro [ 49 ], yam [ 50 , 51 ], sweet potato [ 43 , 52 ], acha and iburu [ 53 ], kidney bean [ 54 ], lentil [ 43 ], and barley [ 16 ]. Investigations have been carried out with native starch (non-modified) and with starch modified using physical and chemical methods—porous starch [ 11 ], retrograded starch [ 41 , 42 ], starch nanocrystals [ 11 ], carboxymethyl starch [ 55 ], starch coated with nanoparticles [ 56 ], and alkaline starch suspension [ 57 ].…”

“…Another procedure of “dry” esterification was described by Kim and Min [ 36 ]. The reaction was induced by microwave-discharged cold plasma.…”

“…The changes observed on the surface of the esterified starch granules included corrosion and fissures. These changes were noticeable in modified preparations produced with the “wet” method [ 50 , 53 , 54 ], through roasting (the “dry” method) [ 37 , 38 , 43 , 44 , 47 , 51 , 60 ], with the electrochemical method [ 33 ], through microwave discharged cold plasma [ 36 ], and with the reactive extrusion method [ 34 ]. Their intensity was varied, and in extreme cases, it led to changes in starch granularity [ 33 , 49 , 58 ].…”

“…Butt et al showed that the swelling power of cold-water-soluble rice starch citrates prepared with the alcoholic-alkaline method was higher than that of the native starch [ 38 ]. Higher swelling power compared to the native corn starch was also exhibited by the preparations produced using microwave-discharged cold plasma [ 36 ]. Lee et al [ 58 ] demonstrated a correlation between swelling power and pH value of the esterification reaction, whereas the work by Kapelko-Żeberska et al [ 42 ] demonstrated a correlation between swelling power and roasting temperature.…”