Submitted to: American Chemical Society National Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 12/16/2011
Publication Date: 3/25/2012
Citation: Tunick, M.H., Van Hekken, D.L., Guo, L., Tomasula, P.M. 2012. Chemistry of Queso Fresco. American Chemical Society 243rd National Meeting Abstracts. AGFD:0045.
Technical Abstract: Queso Fresco (QF), the most popular Hispanic cheese in the U.S. and Mexico, was fully characterized in a series of studies intended to improve quality traits. QF is a non-melting variety made with rennet and without starter culture, and the curd is finely milled to ensure a crumbly texture. In northern Mexico, QF is traditionally made from raw milk and has more moisture, cohesiveness, and shear strain, and lower hardness and shear stress, than QF made in the U.S. from pasteurized milk. Although QF normally contains up to 3% NaCl, lowering the NaCl content to 1.5% does not substantially alter its characteristics. Changing the size of the milled pieces from fine to coarse also has a minimal impact. During storage, activity of nonstarter lactic acid bacteria leads to proteolysis, appearance of volatile compounds presumably generated from lipolysis, and decreases in lactose and pH levels, though the pH stays over 6.0. Texture, torsion, color, melt, and microstructure do not change appreciably over 8 wk of storage, the typical shelf life for QF in the U.S. A full knowledge of the qualities of QF will enable cheesemakers to create a better product.