Samples of Halloumi cheese prepared from either cow's milk or ewe's milk were rheologically tested at various time intervals during ripening. Dynamic tests showed that despite the absence of microbiological and biochemical factors, which normally affect cheese ripening, due to severe heat treatment of the curd during cheese making, the structure of the cheese weakened with the time. This behaviour of the cheese during mechanical testing was attributed to physicochemical factors which govern the structural changes of Halloumi on ripening. (c) 2005 Elsevier Ltd. All rights reserved.