Procedure for the concentration of grape must; see at RCGM.
Abbreviation for rectified grape must concentrate. Rectification is a thermal separation process for separating a homogeneous solution of two or more substances by repeated distillation or countercurrent distillation. This results in a concentration of all soluble substances. The result is a product without the caramel taste caused by heating in other processes. It is produced by partial dehydration using various methods. This is also the difference to concentrated grape must. It is mostly produced by vacuum evaporation of grape must at very low temperatures to prevent the undesirable caramel taste (therefore fire heat is...
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)