Secondary wine

Since it appears that anthocyanins and tannins condense in wine to form secondary wine pigments, the nature of the linkage between these compounds has been the focus of many investigations. There are a large number of possibilities but this chapter will discuss only two for historical purposes. Others will be discussed by other authors in this book. Based upon the structure of a natural compound, Jurd synthesized a dimer from catechin and a synthetic anthocyanidin (Figure 1). The flavylium form of the anthocyanidin has an electrophilic carbon at C-4 that will condense with the phloroglucinol ring of catechin. The new product, a flavene, will be oxidized by a second flavylium... 

Sektion,/. section (.Med.) dissection. Sektwein, m. dry wine, sekunddr, a. secondary. 

Microorganisms have been identified and exploited for more than a century. The Babylonians and Sumerians used yeast to prepare alcohol. There is a great history beyond fermentation processes, which explains the applications of microbial processes that resulted in the production of food and beverages. In the mid-nineteenth century, Louis Pasteur understood the role of microorganisms in fermented food, wine, alcohols, beverages, cheese, milk, yoghurt and other dairy products, fuels, and fine chemical industries. He identified many microbial processes and discovered the first principal role of fermentation, which was that microbes required substrate to produce primary and secondary metabolites, and end products. 

In some cases, a secondary fermentation is encouraged. The wine is then racked or filtered to remove yeast cells and other solids and bottled. 

Called wine of the Naha secondary wince. Ditto. 

The beat red wines in the Island, of excellent body, like the secondary Rhone growths ... 

Tokay, Essence, and Ausbruch Tokay, Masks a Gyrengysesch / Near Ml, Tokay, > L Hungary ) / Mount Matra, 1 (.Upper Hungary j" See wines of firit class. A secondary Tokay. Wines, both red and white, much esteemed. ... 

Rankine (6, 38) believes that the differences in the secondary products formed in wines during fermentation by various yeasts are quantitative rather than qualitative, and careful selection of pure yeast strains can eliminate wine disorders caused by large amounts of undesirable by-products such as hydrogen sulfide, mercaptans, acetaldehyde, acetic acid, ethyl acetate, higher alcohols, etc. 

Chemical Analysis. It is suggested that a set procedure be established for running specific analyses according to a specific timetable. For example, a visual and taste inspection of all wines every two weeks (two months for wines in barrels), malic and lactic acid analyses at weekly intervals during the malo-lactic secondary fermentation, and S02 and color analyses of white wines at least every two weeks until the wine is bottled. Basic analyses to monitor are V.A., S02, alcohol, pH, and T.A. 

Krause et al. (44) extensively studied the derivatization with DBS, proposed by Chang et al. (76), since DBS reacts with both primary and secondary amines and amino acids at room temperature, leading to stable products detectable in the visible region with high sensitivity. In particular they developed a method for the analysis of BAs, together with the AA, in cheese, seasonings, rice wine, and ham. The deproteinized samples (by ultrafiltration or acidification with TCA) were derivatized with an automated precolumn method and analyzed by RP-HPLC-UV. The DBS derivatization was successively applied to study the occurrence of BAs and free AA in raw-milk cheese (detection at 436 nm). They found that the proportions of free AA and BAs relative to the total amount fell into three broad groups that were independent of the type and ripeness of the cheese (77). 

Malolactic fermentation (MLF) is an important secondary fermentation that occurs in many wines generally about 2-3 weeks after completion of the alcoholic fermentation. Lactic acid bacteria, principally Oenococcus oeni (formerly Leuconostoc oenos) are responsible for this fermentation. 

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