ABSTRACTThe stress relaxation behaviour of Gouda cheese cylinders with a diameter/length ratio of 0.7 was studied at compression rates of 5 and 100 cm min‐1. Tests were made in three ways: (1) normal test procedure i. e., the samples were not lubricated, (2) with the samples' upper and lower ends lubricated with mineral oil, (3) with emery paper inserted between the samples and the compression plates so as to exaggerate the friction effects. Surface friction affected stress relaxation behaviour using the normal and emery paper test procedures at compressions up to about 20. At higher concentrations cracks are initiated and propagated in all three test procedures. The values of the rheological parameters derived from relaxation data obtained using compressions not exceeding 20 were lower for lubricated samples. This is attributed to the elimination of that component of the initially applied force which was required to overcome surface friction and which does not decay with time, in contrast to the component actually involved in the initial compression which exhibits stress relaxatio
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