Effects of Preheating Temperature, Moisture and Sodium Metabisulfite Content on Property of Maize Flour Dough

Processing temperature, maze flour particle size, and level of water and sodium metabisulfite were varied during the preparation of maize noodles. Preheated to 90—95 ℃ a mixture of maize flour or meal, water(43%—45% moisture) and salt enabled the preparation of noodles using a pasta extruder. Maize flour with smaller particle size yielded better noodles than did maize meal. The addition of sodium metabisulfite enabled the production of noodles at lower processing temperatures; however, cooking losses increased. Processing maize flour with higher water absorption yielded noodles that required longer cooking time but with decreased losses. The functionalities of starch and protein in raw ingredients and in products were determined. Starch gelatinized and retorgraded during processing maize noodles, as indicated by changes in pasting viscosity curves. Maize proteins contributed to the increased viscosity of dough above 40 ℃. The increased integrity of cooked maize noodles, however, corresponded to the increased amounts of gelatinized and retrograded starch.

Effective Sodium Metabisulfite (Na₂S₂O₅), HCl, Sulfur and Distilled Water for the Removal of Pb, Zn and Cr Contaminated Soil in the Columns Method

This paper presents an evaluation of different dose of Sodium Metabisulfite (0.01 M Na2S2O5), (Na2S2O5) + (0.1 HCl), and Distilled water for the removal of soil contaminated with Pb, Zn and Cr by the column mode. The field soil contained concentrations of Pb (307.31 mg⋅kg−1), Zn (207.77 mg⋅kg−1) and Cr (447.50 mg⋅kg−1). Both (0.01 M Na2S2O5), (Na2S2O5) + (0.1 HCl), and Distilled water were found to be effective on removing (Na2S2O5) Pb, Cr and Zn respectively. (Na2S2O5) + (0.1 HCl) Cr, Zn and Pb respectively. Sulfur Pb, Cr and Zn respectively. The removal rate of Pb, Zn, and Cr varied from 10.35% - 26%, 3.4% - 21.60% and 4.97% - 23.88% for (0.01 M Na2S2O5 respectively. The removal rate of Pb, Zn, and Cr varied from 16.13% - 20.07%, 8.20% - 23.48%, 5.42% - 28.93% for (0.01 M Na2S2O5 + 0.1 M HCl) respectively. The removal rate of Pb, Zn, and Cr varied from 10.20% - 25.5%, 9.55% - 25.13% and 6.04% - 25.54% for (S) respectively.

Transition-Metal-Free Reductive Cross-Coupling Employing Metabisulfite as a Connector:General Construction of Alkyl–Alkyl Sulfones

A multicomponent reductive cross-coupling of unactivated alkyl halides and alkyl tosylates connected via sodium metabisulfite was established for the general construction of alkyl-alkyl sulfones.Neither a metal catalyst nor a metal reductant is required in this“green”reductive cross-coupling.Inorganic sodium metabisulfite served as both the sulfur dioxide source and the robust connector.

TFA promoted multi-component reaction of aryldiazonium with sodium metabisulphite and thiols:Construction of thiosulfonate under transition-metal free conditions

A TFA promoted multi-component reaction of aryldiazonium with sodium metabisulphite and thiols to construct thiosulfonates under transition-metal free conditions is reported.The thiosulfonates were isolated in good yields with broad tolerance of functional group.Readily available inorganic Na2S2O5 was applied as the sulfur dioxide surrogate.This strategy features easily available substrates,mild reaction conditions and free transition-metal catalyst.