This paper gives the results of a comprehensive series of tests on the corrosion of four different grades of aluminium and two aluminium alloys by a dilute acid and an acid‐salt solution at different temperatures under static and agitated conditions. The work was undertaken to provide information of practical value on some of the main factors influencing the service‐life of aluminium plant and equipment used in contact with acid food products.The results show that aluminium (purity range 99.25–99.993%), Al‐Mn (1.17% Mn) and Al‐Mg‐Mn (1.78% Mg, 0.45% Mn) alloys resist a dilute solution of citric acid at room temperature whether agitated or not. The rate of corrosion was approximately doubled per 10° C. rise in temperature; the life of equipment would be very short at boiling temperature. In the presence of salt, the corrosion rates of the two alloys and of all the grades of aluminium tested, with the possible exception of the purest grades, would be too high to permit their use even at room temperatures, unless oxygen was excluded. In general, the corrosion was greater the lower the grade of aluminium and, under all but one of the conditions tested, the two alloys corroded most.