Beef marinates better in red wine than in white wine.
IT IS SAID THAT FISH MUST BE COOKED in white wine but that red wine should be used to marinate and cook tough meats in order to tenderize them. It is also said that parsley must not be used if the marinating process lasts more than two days and that one should not roast marinated meats because roasting dries them out. How far should we credit these familiar dictums?
Japanese physical chemists recently provided partial corroboration. Experiments conducted some twenty years ago in France, at the Institut National de la Recherche Agronomique station in Clermont-Ferrand, showed that beef is tenderized by prolonged immersion in acid solutions, which dissolve collagen and various other proteins principally responsible for the toughness of raw meats while ionizing these proteins, increasing the amount of water they retain. Vinegar is not the sole ingredient of such marinades, however, and the role of wine in particular remained mysterious. Two researchers in the department of home economics at the University of Koshien in Japan, Kazudo Okuda and Ryuzo Ueda, completed the French study after first examining the effect on meats of fermented products such as vinegar and soy sauce.
Preliminary investigations established that the mass, water content (the tenderness of meats depends particularly on their juiciness, which is to say their water content and the ease with which this water is released), and texture of meats that were boiled after having first been marinated in these solutions were modified by five ingredients: alcohol, organic acids, glucose, amino acids, and salt.
Decisive Marinades
In 1995 Okuda and Ueda extended this study by analyzing samples of beef that were boiled after having been marinated in white wine, in red wine, and in solutions containing only certain components of wine. The samples used (cubes of meat weighing about 50 grams, or a bit less than 2 ounces) were marinated for three days, then boiled for ten minutes or so. The outer part and the inner part were analyzed separately. The water content and mass of the samples marinated in red wine were slightly greater than those of the samples marinated in white wine, but the masses of dry matter were about the same. In other words, red wine marinades did a better job of preserving the tenderness of the meats.
Furthermore, the maximal resistance to internal compression was clearly lower in the case of the samples marinated in red wine, which is to say that red wine marinades also did a better job of tenderizing the meats. Finally, after cooking, both the inner and outer parts of the samples marinated in red wine were more tender than the ones marinated in white wine and also more tender than samples cooked without having been marinated.
How are these advantages to be explained? Okuda and Ueda previously showed that the effects of sugars, amino acids, and inorganic salts are weak but that red wines contain more polyphenols than white wines because they are generally more tannic and highly colored (tannins and anthocyanins, the natural color pigments in wine, are polyphenols). Because polyphenols react chemically with proteins, the two researchers tested their effect by marinating the same meats in trial solutions containing fixed concentrations of tannic acid (representing the polyphenols), organic acids, and ethanol.
Solutions composed of water, ethanol, and organic and tannic acids (such as the ones found in red wine) modified the meat in the same way as red wine alone, suggesting that red wine marinades act primarily through organic acids and tannic acid; ethanol and, to a lesser degree, organic acids are important during cooking.
The molecular details of these reactions are being studied, but it appears that proteins react with the polyphenols found in red wines in such a way as to seal the juices of the meat by hardening, or caking, its surface. Classic recipes therefore are justified in recommending that a combination of red wine and acidic liquids, such as vinegar, be used for tenderizing meats. It now remains to elucidate the mysteries associated with the roasting of marinated meats and the proper use of parsley.