Flour sulfite, additive

The reducing capacities of sulfite should be emphasized as well. In fact, cleavage of S-S bonds by sulfite can be considered a reduction. This property of sulfite makes it useful as an additive to flour for biscuit making (Wedzicha, 1995). The cleavage of disulfide bonds in wheat proteins speeds up and facilitates the production of a satisfactory dough. 

The fermentation process can be artificially controlled and impeded by the addition of sulfur dioxide or potassium metabisulfite. The addition of this preservative poses a potential health hazard. The residual sulfites present in wine have been known to elicit urticaria, asthmatic reactions and respiratory failure. In the United States, since 1987, warning labels indicating the presence of sulfites must appear on wine bottles containing at least 10 ppm of sulfites (Fisher 1997)- In addition to their importance in wine making, sulfur dioxide and sulfites are used as food additives for their antimicrobial effect. Contact dermatitis to potassium metabisulfite has developed in a pharmaceutical worker (Nater 1968) and may also occur in bakers, from occupational exposure to flour (Apetato and Marques 1986), and in hairdressers to permanent wave solution, but has not been reported in winemakers. Sulfur dioxide has also been reported to cause contact urticaria (Maibach and Johnson 1975). 

The results of studies focused on changes in the content of trichothecenes in the production of bread and other bakery products are sometimes very different, nevertheless some decrease in contamination of flour was observed, especially in fermented products, where the losses of deoxynivalenol ranged from 15 to 56%. A decrease in concentrations of deoxynivalenol (up to 40%) and some other mycotoxins (nivalenol and acetyloxynivalenols) also occurs after the addition of sulfites to the dough, as sulfites react with trichothecene mycotoxins with the addition to the C-9/C-10 double bond yielding the corresponding hydroxysulfonates. A significant reduction in the content of trichothecenes, especially... 

The typical sodium salts include sodium fluoride, trisodium phosphate, soda ash, sodium bicarbonate, sodium sulfite, and others. The lime and sodium fluoride are essential for ready liquefaction of the glue. Casein may be dissolved with only lime, but this type of adhesive remains fluid only a short time before gelling. Additives, including defoamers and zinc compounds, and extenders, such as clays, wood flour, and shell flour, are frequently used. 

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