The invention relates to a process for producing alkyl esters, the process comprising reacting a feedstock that includes one or more fatty acid glycerol esters or one or more fatty acid or mixture thereof with a C1 to C4 alcohol in the presence of a catalyst at a temperature substantially 100° C or more, the catalyst including a catalyst composition comprising oxides, mixed oxides, silicates or sulphates of two or more of silica, aluminium, iron, calcium, magnesium, sodium and potassium.