TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: Alternatively, producing biocombustible and biofuel mixtures suitable for different conditions of use, involves: (a) pre-treating lipid-based vegetable or animal materials, where the lipid based vegetable or animal materials comprises used food oil and/or animal fats and at least one of raw vegetable oil and refined vegetable oil, and where the pretreatment involves: (i) if using the raw vegetable oil, subjecting the raw vegetable oil to a preliminary depuration and refining treatment to remove impurities and to neutralize and winterize the raw vegetable oil, and drying the refined oil thus obtained; (ii) if using the refined vegetable oil, subjecting the refined oil to preliminary drying; (iii) subjecting the used food oil and/or animal fats to a preliminary depuration treatment, drying and an esterification of the free fatty acids contained by addition of lower alcohols or bioalcohols to obtain an esterified product of the used food oil and/or animal fats; (b) mixing the esterified product of the used food oil and/or animal fats in a proportion of not not greater than 20% with dried refined oil obtained from steps (i) and/or (ii); (c) producing mixtures of fatty acid alkyl esters and glycerine by transesterification of the product of step (b) with lower alcohols of bioalchohols in excess; and (d) separating the mixtures obtained from the step (c) of transesterification into a phase containing raw glycerine and a phase containing the mixtures of fatty acid alkyl esters and the excess amount of lower alcohols or bioalcohols; where, after the step (d) of separation, the phase containing the mixtures of fatty acid alkyl esters and the excess amount of lower alcohols or bioalcohols is either: (e1) not subjected to further separation treatments; or (e2) subjected to flash evaporation to separate part of the excess amount of lower alcohols or bioalcohols where the final biocombustible and biofuel mixture contains mixtures of fatty acid alkyl esters and a calibrated quantity of alcohols and/or bioalcohols. Producing biocombustible and biofuel mixtures suitable for different conditions of use, involves: (a) producing mixtures of fatty acid alkyl esters and glycerine by transesterification, starting from lipid-based vegetable or animal materials and from lower alcohols or bioalcohols in excess; and (b) separating the mixtures deriving from the operation (a) of transesterification into a phase based on raw glycerine and a phase containing the mixtures of fatty acid alkyl esters and the excess amount of lower alcohols or bioalcohols; where the starting lipid-based vegetable or animal materials include one or more of the following ingredients: (i) raw vegetable oil, (ii) refined vegetable oil, or (iii) used food oil and/or animal fats, and the ingredients undergo the following preliminary treatments upstream of the operation (a) of transesterification: (1) the ingredient (i), raw vegetable oil, is subjected to a preliminary depuration and refining treatment in order to remove impurities and to neutralize and winterize it, and then to drying of the refined oil thus obtained; (2) the ingredient (ii), refined vegetable oil, is subjected to preliminary drying; and (3) the ingredient (iii), used food oil and/or animal fats, is subjected to a preliminary depuration treatment, to drying and then to an esterification of the free fatty acids contained in it, by addition of lower alcohols or bioalcohols; the obtained product based on fatty acid alkyl esters is mixed in a proportion of not not greater than 20% with dried refined oil obtained from treatments (1) or (2) above. In producing biocombustible and biofuel mixtures, after the step (d) of separation, the phase containing the mixtures of fatty acid alkyl esters and the excess amount of lower alcohols or bioalcohols is subjected to a further separation treatment to remove a portion of the alcohols or bioalcohols present after the step (d) of separation. After step (d) of separation, the phase containing the mixtures of fatty acid alkyl esters and the excess amount of lower alcohols or bioalcohols is not subjected to further separation treatments, and the whole excess quantity of lower alcohols or bioalcohols is kept in the final product. After step (d) of separation, an additional amount of lower alcohols or bioalcohols is added to the phase containing the mixtures of fatty acid alkyl esters and the excess lower alcohols or bioalcohols. Step (c) of transesterification is carried out with an alkaline catalyst. It is carried out in three consecutive stages in which the alcohols or bioalcohols and the catalyst are dosed and recycled at every stage. The preliminary treatment (i) of depuration of raw vegetable oil involves operations of centrifugation, filtration and demucilagination. After the operation (b) of separation, the phase containing the mixtures of fatty acid alkyl esters and the excess amount of lower alcohols or bioalcohols is subjected to a further separation treatment for the separation of amounts of 0-100% of the alcohols or bioalcohols present after the operation (b) of separation. After the operation (b) of separation, the phase containing the mixtures of fatty acid alkyl esters and the excess amount of lower alcohols or bioalcohols is not subjected to further separation treatments, and the whole excess quantity of lower alcohols or bioalcohols is kept in the final product. After the operation (b) of separation, an additional amount of lower alcohols or bioalcohols is added to the phase containing the mixtures of fatty acid alkyl esters and the excess lower alcohols or bioalcohols. The operation (a) of transesterification is carried out with an alkaline catalyst; or the operation (a) of transesterification is carried out in three consecutive stages in which the alcohols or bioalcohols and the catalyst are dosed and recycled at every stage. Preliminary treatment (1) of depuration of ingredient (i), raw vegetable oil, involves operations of centrifugation, filtration and demucilagination. Preliminary treatment (1) of depuration of ingredient (i), raw vegetable oil, involves neutralization and winterizing operations. Preferred Component: The lower alcohols or bioalcohols are selected from methanol, ethanol, biomethanol, bioethanol and its mixtures. Preferred Composition: The amount of lower alcohols or bioalcohols corresponds to an excess alcohol or bioalcohol initially present in the transesterification process; or the amount of lower alcohols or bioalcohols is greater than an excess alcohol or bioalcohol initially present in the transesterification process, and is obtainable in the mixture by addition after the transesterification process; or the amount of lower alcohols or bioalcohols is smaller than an excess alcohol or bioalcohol initially present in the transesterification process. EXAMPLE - No suitable example given.