Rheological and microstructural changes in Queso Fresco during storage

Authors: Tunick, Michael; Van Hekken, Diane

Submitted to: American Chemical Society National Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 12/2/2009
Publication Date: 3/21/2009
Citation: Tunick, M.H., Van Hekken, D.L. 2009. Rheological and microstructural changes in Queso Fresco during storage. American Chemical Society National Meeting. AGFD 130.

Interpretive Summary: n/a

Technical Abstract: Queso Fresco is a traditional Hispanic cheese that is increasing in popularity in the United States. Rheological and microstructural studies were performed on samples refrigerated at 4 and 10 deg C for up to 8 wk. The hardness of all cheeses as measured by texture profile analysis (TPA) was low and within a narrow range. In the cheeses stored at 10 deg C, the TPA cohesiveness decreased with time, indicating structural breakdown; the cheeses stored at 4 deg C showed a small decrease. The elastic and storage moduli for the 4 deg C samples increased with storage time, but the moduli for the 10 deg C samples did not. Torsion shear stress and shear strain increased for all samples from 1 to 8 wk. Scanning electron microscopy revealed that the protein matrix was tighter and less open for the 4 deg C cheeses. The results show that Queso Fresco stored at 4 deg C retains its internal structure to a greater extent than cheeses stored at 10 deg C, which indicate that keeping this cheese well-refrigerated is important for retaining its textural quality.