Polyvinylpolypyrrolidone

Wine and beer industry Polyphenols can alter color and flavor of products such as wines. There are many aggressive ways of removing polyphenolic compounds, such as using polyvinylpolypyrrolidone (PVPP) or sulfur dioxide. However, polyphenol removal should be selective to avoid the undesirable alteration of the wine s organoleptic characteristics. For this reason, one option is to use laccases that polymerize the polyphenolic compounds during the wine-making process and then to remove these polymers by clarification (Morozova and others 2007). Several papers have reported that laccase is able to remove undesirable polyphenols and produce stable wines with a good flavor. 

As required by Directive 89/107/EEC, criteria of purity have been drawn up for all the listed food additives (with a couple of exceptions). Purity criteria for all the permitted sweeteners have been prescribed in Directive 95/31/EC,6 as amended, and criteria for all the permitted colours are contained in Directive 95/ 45/EC,7 as amended. Directives that prescribe purity criteria for all the additives authorised under Directive 95/2/EC have been drawn up in stages. Directive 96/ 77/EC8 containing purity criteria for antioxidants and preservatives is amended by Directives 98/86/EC which lays down purity criteria for emulsifiers, stabilisers and thickeners and 2000/63/EC which contains purity criteria for most additives numbered E 500 and above, and for certain other additives not covered in the earlier directives. Purity criteria for most of the few remaining permitted miscellaneous additives are contained in Directive 2001/30/EC however, purity criteria for E 1201 polyvinylpyrrolidone and E 1202 polyvinylpolypyrrolidone are still being considered by the Scientific Committee on Food. Some methods of analysis for verifying prescribed purity criteria have been developed at EU level these are contained in Directive 81/712/EEC.9... 

E 1103 Invertase E 1105 Lysozyme E 1200 Polydextrose E 1201 Polyvinylpyrrolidone E 1202 Polyvinylpolypyrrolidone E 1404 Oxidised starch E 1410 Monostarch phosphate E 1412 Distarch phosphate E 1413 Phosphated distarch phosphate E 1414 Acetylated distarch phosphate E 1420 Acetylated starch E 1422 Acetylated distarch adipate E 1440 Hydroxy propyl starch E 1442 Hydroxy propyl distarch phosphate E 1450 Starch sodium octenyl succinate E 1451 Acetylated oxidised starch E 1505 Triethyl citrate E 1518 Glyceryl triacetate (triacetin)... 

McMurrough, I., Madigan, D., and Kelly, R. J. (1997). Evaluation of rapid colloidal stabilization with polyvinylpolypyrrolidone (PVPP). J. Am. Soc. Brew. Chem. 52, 38-43. 

Polyvinylpolypyrrolidone Potassium Alginate Potassium Citrate Potassium Polymetaphosphate Potassium Tripolyphosphate Povidone PVP... 

Apart from salivary proteins, other proteins have been used in studies of kind mucin [56], gliadin [49], pl-glycosidase [32, 59], hemoglobin [60], and BSA [24, 35-37, 48, 61-64]. Other proteins have been used because of certain characteristics that make them similar to proline-rich proteins (PRPs), like casein [33, 65], gelatin [42, 49, 65-67], and polyproline [34, 66, 68]. Although it is not a protein, the polymer polyvinylpolypyrrolidone has also been used in these studies [68, 69]. 

Another major fining procedure in Interior Valley table wine production is use of the compound PVPP (polyvinylpolypyrrolidone) (12). This reacts principally with tannins and is used to reduce browning in white wines. This results from its affinity for catechin, the main substrate for browning reactions. This compound also is used widely in the brewing industry. 

Polyvinylpolypyrrolidone occurs as a white to off white, hygroscopic, free-flowing powder. It is a crosslinked homopolymer of purified vinylpyrrolidone, produced catalytically. It is insoluble in water and in other common solvents. 

To determine RuBisCO contents, leaf tissues were quick-frozen in liquid nitrogen then homogenized with a mortar and pestle in a buffer containing 50 mM HEPES-KOH (pH 7.6), 1 mM dithiothreitol, 2% polyvinylpolypyrrolidone, ImM phcnylmethylsulfonylfluoride and... 

Polyvinylpolypyrrolidone Chemically incorrect designation often encountered in the food bterature... 

The designation polyvinylpolypyrrolidone (PVPP) is still used in the literature, although it is certainly not correct. This is confirmed by a comparison of the infrared spectra for crospovidone and povidone, which reveals no recognizable difference (see Section 3.3.1.1). 

Crospovidone is usually registered as polyvinylpolypyrrolidone or PVPP -in the USA for clarifying beverages and vinegar [488] and in all european and many other countries for stabilizing and clarifying beer and wine. 

K. Takayama, H. Imaizumi, N. Nambu, and T. Nagai, Mathematical optimization of formulation of indomethacin/polyvinylpolypyrrolidone/methyl cellulose solid dispersions by the sequential unconstrained minimization technique, Chem. Pharm. Bull., 33, 292-300 (1985). 

The polymerization of vinylpyrrolidone prodnces water-solnble polyvinylpyrrolidone (PVP). However, if polymerization occurs in the presence of an alkali, the pyrrolidone cycle is broken, pro-dncing insolnble polyvinylpolypyrrolidone (PVPP) (Fignre 10.14). 

Fig. 10.14. Polymerization of vinylpyrrolidone into (a) polyvinylpyrrolidone (PVP) and (b) polyvinylpolypyrrolidone (PVPP)...

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