Non-linear stress relaxation model as a tool for evaluating the viscoelastic properties of meat products

• Our non-linear model describes rheological behavior of meat products.
• The model was validated for pork and poultry cold cuts available throughout Poland.
• The model adequately describes changes in stress in all phases of the relaxation test.
• The proposed model can be used to optimize the cold cut production process.

A non-linear rheological model was developed for processed pork and poultry meats. The modeled parameters were identified based on the results of compression stress relaxation tests at a constant strain rate in initial (compression) and final (expansion) phases of the test and at constant deformation values in the principal stage of the test (stress relaxation). The analyzed material comprised processed pork and poultry meats which are supplied by renowned manufacturers and are available in retail throughout Poland. The proposed rheological model of the analyzed processed meats was logically and empirically validated, and it adequately described changes in stress in all three phases of the relaxation test. Significant differences were observed in the rheological properties of processed meats that belonged to the same processing groups, but were made of different meat (pork or poultry). Significant correlations were noted between the proximate chemical composition and rheological properties of the analyzed products. The proposed rheological model can be used to optimize the production of processed meats.