Technical Abstract: The chemical, rheological, textural, functional, and sensory aspects of Queso Fresco, a popular Hispanic cheese variety made without starter culture and with a pH over 6, were evaluated during storage at 4 and 10 deg C. Decreases in lactose and pH levels were observed and attributed to activity by nonstarter bacteria. The appearance of volatile compounds derived from lipids indicated that lipolysis was taking place, and some proteolysis was also noted in electrophoresis studies. The cheese had a characteristic crumbly body and was bright white and non-melting. Minor variations in texture profile, torsion, color, and melt analyses were seen throughout 8 wk of storage. No microstructural changes were seen. A consumer taste panel generally liked two commercially-made cheeses and a cheese made in our pilot plant, and could not distinguish one of the commercial samples from the pilot plant sample. The results provide a basis for assessing the quality traits of Queso Fresco.