Shredded Cheddar Cheese: Accelerating Shreddability by Moderate Hydrostatic Pressure (MHP)

Principal Investigator:

J. A. Torres, OSU

Co-Investigators:

D.F. Farkas, OSU
G. Vel�zquez, OSU, Mexico
J. Salas, CICATA, Mexico
M. McDaniel, OSU E.
Morales, U. Austral, Chile
J.A. Ram�rez de Le�n, U.A. Tamaulipas, M�xico
J. Serrano, OSU & U.A. Quer�taro, M�xico
R. Alfaro, OSU & I.T.E.S. de Monterrey, M�xico

Project Summary:

Cheese production in the United States has increased to ~730 million tons/month due in significant part to the demand for natural shredded cheese. There is great consumer interest in shredded cheese not only in the US but also elsewhere in the world. Shredded cheese has become the most common ingredient cheese sold through U.S. retail, food-processing and foodservice channels. Many natural cheeses can be grated but storage costs before a given variety reaches shreddability are significant. These costs include refrigerated storage space and inventory keeping which require a large capital investment.

In previous work, we discovered that moderate pressure treatments applied to fresh curd yield immediately a microstructure similar to aged Cheddar cheese. In this project we are determining if these pressure treatments and microstructure effect can shorten the storage needed before shredding Cheddar cheese. We are uniquely qualified to evaluate this opportunity as our pilot plant is equipped with a 20-liter pressure vessel which is ideal to prepare the large number of samples required for sensory and objective measurements. In addition, we work closely with Avure Technologies (formerly Flow International Inc., Kent, WA) and we can use their commercial high-pressure prototype units whenever appropriate.

Relatively little information has been published on the mechanical properties making cheese blocks suitable for shredding. Texture measurement procedures found in the literature differed in test parameters and those had to be evaluated to find the most adequate conditions for our experimental samples. Also missing was a definition of consumer-acceptable shredded cheese. This information was generated by a trained descriptive sensory panel that examined the appearance of pressure treated, control and commercial shredded Cheddar cheese. Objective measurements of shreddability include a computerized vision system built by co-PI Salas and microstructure determinations by electron microscopy. Our experimental vision unit can characterize the size/shape of the shredded cheese and has an area measurement tool used to assess cheese meltability.

Examination of the first replicate in our experimental design led to the following project revisions: (1) project scope expansion by including Cheddar cheese manufactured by milled and stirred curd technologies; (2) pressure treatment of cheese blocks collected right after cooling which were shredded immediately and after storage for up to 27 days; (3) selection of pressure treatments of 3 and 7 minutes at 50,000 and 70,000 psi to include moderate pressure levels below and slightly above the 60,000 psi pressure technology barrier (Figure 2); (4) improvement of the evaluation of mechanical properties; (5) improvement of the image analysis software which will be implemented for the analysis of the shredded cheese for final consumer studies.

Trained sensory panel evaluations following the modified project procedures demonstrated that MHP could be used to generate streamlined production technology for shredded cheese (Figure 3). Cheese blocks coming from the cooling unit can be pressure treated, shredded and packaged immediately for distribution to consumers. Most importantly, this technology will work with relatively low pressure (i.e., 50,000 psi). Furthermore, the properties of pressure treated and control samples are practically identical after 15 days of refrigerated storage meaning that we can accelerate and streamline the production of shredded cheese with the properties known to be acceptable to consumers. Conclusions based on the trained sensory panel observations were confirmed by objective measurements.

Publications:

Salas, J., Vel�zquez, G., and Torres, J.A. 2002. Un algoritmo para la medici�n en l�nea de la longitud de tiras flexibles sobrepuestas. Proceedings of the Simposio de Metrolog�a 2002, Quer�taro, M�xico.

Book Chapters

1. Mendoza-Sánchez, P., López, D., Kongraksawech, T., Vazquez, P., Torres, J.A., Ramirez, J.A., Huerta-Ruelas, J. 2005. Laser metrology in food related systems. Proceedings of the Eighth International Symposium on Laser Metrology, International Society for Optical Engineering, R. Rodriguez-Vera, F. Mendoza-Santoyo (editors), vol. 5776, p. 347-354.

2. López, D., Mendoza-Sánchez, P., Torres, J.A., Ramos, G., Pless, R.C., Huerta-Ruelas, J. 2004. Optical rotation measurements in food industry processes. In Proceedings of the Internacional Simposio de Metrología, Oct 25-27, Querétaro, México.

3. Velazquez, G., Vazquez, P., Torres, J.A. 2004. Altas Presiones en la Industria Alimentaría: I. Consideraciones Comerciales en el Procesamiento de Alimentos por Alta Presión. In Proceedings of the International Congress of Food Safety, p. 259-277, Reynosa, Tamaulipas, October 12-15, México.

4. Velazquez, G., Vazquez, P., Torres, J.A. 2004. Altas Presiones en la Industria Alimentaría: II. Retos Actuales de Investigación en el Procesado de Alimentos a Altas Presiones. In Proceedings of the International Congress of Food Safety, p. 279-306, Reynosa, Tamaulipas, October 12-15, México.

5. Mendoza-Sánchez, P., López, D., Ramos, G., Pless, R., Huerta-Ruelas, J., Torres, J.A. 2004. An optical rotation measurement system to control processes in the food industry and to study thermal denaturation of food proteins. In Memorias del Simposio de Metrología. Centro Nacional de Metrología (CENAM). Querétaro, México.

Refereed Journal Articles

6. López, D., Mendoza-Sánchez, P., Kongraksawech, T., Velazquez, G., Huerta-Ruelas, J., Torres, J.A. 2005. In-line/real-time optical polarization measurements in food systems. Journal of Food Engineering.

7. Ramirez, J.A., Tirado, J., Serrano, J., Morales-Blancas, E., Velazquez, G., Torres, J.A. 2005. Characterization and shredding of high pressure treated stirred curd Cheddar cheese. Journal of Texture Studies.

8. Ramirez, J.A., Tirado, J., Serrano, J., Morales-Blancas, E., Velazquez, G., Torres, J.A. 2005. Mechanical, biochemical and SEM characterization and shredding of high pressure treated milled curd Cheddar cheese. Journal of Sensory Studies.

9. Vazquez-Landaverde, P. A., G. Velazquez, J. A. Torres, M. C. Qian. 2005. Solid-phase microextraction of volatile sulfur compounds in milk and quantification by gas chromatography coupled to pulsed-flame photometric detection. Journal of Dairy Science.

10. Vazquez-Landaverde, P. A., G. Velazquez, J. A. Torres, M. C. Qian. 2005. Quantitative determination of thermally derived volatile compounds in milk using solid-phase microextraction and gas chromatography. Journal of Dairy Science.

11. Velazquez, G., Vázquez, P., Vázquez, M., Torres, J.A. 2005. High pressure food processing applications. Ciencia y Tecnologia Alimentaria 4(5): 343-352.

12. Velazquez, G., Vázquez, P., Vázquez, M., Torres, J.A. 2005. Advances in the food processing by high pressure. Ciencia y Tecnologia Alimentaria 4(5): 353-367.

13. Torres, J.A., Velazquez, G. 2005. Commercial opportunities and research challenges in the high pressure processing of foods. J. Food Eng. 67: 95-112.

14. Serrano, J., Velazquez, G., Lopetcharat, K., Ramirez, J.A., Torres, J.A. 2005. Moderate hydrostatic pressure processing to reduce production costs of shredded cheese: Microstructure, texture and sensory properties of shredded milled curd Cheddar. Journal of Food Science 70(4): S286-293.

15. Serrano, J., Velazquez, G., Lopetcharat, K., Ramirez, J.A., Torres, J.A. 2004. Effect of moderate hydrostatic pressure on microstructure, texture and sensory properties of stirred curd Cheddar shreds. J. Dairy Science 87: 3172 – 3182.

Theses:

Serrano, J. 2002 (expected December 2002). Master of Science, Universidad Aut�noma de Quer�taro, M�xico.

Published Abstract:

Salas, J., Vel�zquez, G., and Torres, J.A. 2002. Un algoritmo para la medici�n en l�nea de la longitud de tiras flexibles sobrepuestas. Simposio de Metrolog�a 2002, Quer�taro, M�xico.

Presentations:

Salas, J., Vel�zquez, G., and Torres, J.A. 2002. Un algoritmo para la medici�n en l�nea de la longitud de tiras flexibles sobrepuestas. Proceedings of the Simposio de Metrolog�a 2002, Quer�taro, M�xico.