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The effect of high dynamic pressure treatment of milk (200MPa for five 1-min cycles) on the viability of Listeria innocua and on the microbiological, textural and microstructural attributes of Cheddar cheese was investigated. Cheddar cheeses were made from: (A) pressurized whole milk, (B) pressurized skim milk which was standardized with pasteurized cream, (C) whole milk pasteurized at 72°C/15s and (D) pressurized 2% fat milk. The fat contents of milk batches subjected to treatments A–C were standardized to 3.4%. All milks were contaminated with L. innocua at levels of 10⁵–10⁶ colony forming units (cfu)mL⁻¹. Pressurization of milk resulted in a three- to four- log cycle reduction of L. innocua cfu and remarkable reductions in casein micelle and fat globule sizes. Cheeses made from pressurized milk retained more moisture and protein and produced higher yield than those from pasteurized milk. Rheological …