Phenolic antioxidants minimal processing

Several stabilizers are useful in minimizing oxidative degradation during thermoplastic processing or in the bulk solid. Phenothiazine, hindered phenolic antioxidants such as butylated hydroxytoluene, butylated hydroxyanisole, and secondary aromatic amines in concentrations of 0.01—0.5% based... 

In addition, fhiit and vegetables can be minimally processed (washed, pealed, cut, diced, stripped, chopped, etc.) in order to provide ready to eat or ready to use products (salad mixes, apple slices, carrot sticks, diced potatoes, etc.). These minimal processing treatments damage the plant surface and induce changes in phenolic metabolism and phenolic antioxidant composition. 

Several companies now offer combinations of phenolic antioxidant with a phosphite in the same product. Cytec Industries markets a phenolic antioxidant combined with a hydrolysis-resistant phosphite, called Cyanox XS4. The components are both high molecular weight substances, so as to increase permanence and thermal stability. Cyanox XS4 was first targeted at polyolefins, where it was claimed to widen the processing window and reduce costs by allowing less stabiliser to be used, while still achieving minimal discoloration and melt flow. 

Antioxidants are additives that minimize autoxidation reactions. They function as hydrogen atom donors that stop the chain oxidation process of the olefins. The two different types of antioxidants used in gasoline are phenylenediamines (PDA) and hindered phenols (such as BHT). 

PolycarbonatG. Polycarbonate, PC, is susceptible to photo-oxidation, and antioxidants are necessary to maintain the low color and high transparency critical to its end-use applications (see Polycarbonates). Phosphites (0.1%) are used to minimized color development dnring processing. It has been shown that the inherent stability of PC is related to the level of phenolic end groups (41). These levels can increase as a result of hmnidity-induced hydrolysis catalyzed by acid. The phosphite chosen must be very stable to avoid the generation of catalytic amoimts of phosphorus acids. 

Beer phenols issued from malt and hop can contribute directly to several characteristics of beer, mainly color, flavor, astringency, and haze. As antioxidants, they can also protect raw materials from oxidative degradation throughout the process, minimizing therefore off-flavors such as trans-2-nonenal. ... 

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