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An automated technique for the alcoholometric grade determination based upon measurement of dilution heat of ethanol in wine and appropriate reagent was tested. Interferences with wine other components was studied along with methods to minimize them. Two sets of determinations on more than 100 samples of various qualities (red wines, roses wines, white wines) and various geographical sources were performed and they were compared with the pycnometric reference technique. It is shown than this comparative study that for almost 95 p. 100 of the samples the alcoholometric grade can be determined with this automated technique with an accuracy better than 0,1 p. 100.

Automatic dosages took place a short time ago in oenology laboratories. First researchs about automation of usual manual analysis have been completed by I.N.R.A. Station of Dijon during 1969--1972 years. Then, other researchs were made and in 1974 the first automatic analyser appeared in application laboratories. In all cases continuous flow method was used. First dosages which has been carried out are volatic acidity, residual sugars, total SO2. The rate of work is 30 samples an hour. Then, an original way for free SO2 was suggested. At present, about a dozen of laboratories in France use these dosages. The ethanol dosage automation, very important in oenology, is very difficult to carry out. A new method using a thermometric analyzer is tested. Research about many dosages as tartaric, malic, lactic acids, glucose, fructose, glycérol, have been performed especially by I.N.R.A. Station in Narbonne. But these dosages are not current and at present no laboratory apply them. Now, equipments price and redemption, change of tradionnal dosages for automatical methods and the level of knowledge required for operators are well known. The reproducibility and the accuracy of the continuous flow automatic dosages allow, for enough important laboratories, to make an increasing number of analysis necessary for wine quality control.