Determination of Co-value as an indicator of nutritive value of pate sterilised by regular and optimized regime

Abstract

Introduction. Heat treatment of food provides appropriate shelf life and safety, as well as adequate sensory properties and better digestibility, but excessive thermal processing leads to the loss of nutritive value. In practice, sterilised meat products are usually overheated, which leads to a loss of nutritive value. Therefore, it is necessary to find the optimum between the preservative effect of heat treatment and maintenance of the nutritive value of food. Control of the sterilisation efficiency is based on the F_o value, an indicator of the lethal effect of heat treatment, while the cooking (C_o) value indicates a reduction of the nutritive value of heat treated products.

Materials and Methods. During pâté sterilisation processes, two working heat treatment regimes were used: the regime used in regular, commercial production and an optimised regime. Heat treatment measurements were carried out using six thermocouple probes placed in the geothermal centres of six chosen cans. For each heat treatment, schematic diagrams were produced. F_o values were determined using Ellab software, and C_o values by the graphic method in a semi-logarithmic Thermal Death Time diagram.

Results and Conclusions. During pâté sterilisation, where the effective time was 55 minutes (regular regime) at 114 °C and 3.2 bar pressure, an average F_o value of 7.90±0.43 was achieved. By reducing the effective sterilisation time to 45 minutes (optimised regime), an average F_o value of 3.81±0.5 was achieved. Both regimes were sufficient to ensure product safety (F_o >3). The average C_o value for the regular sterilisation regime was 109.83±1.33 minutes, while for the optimised regime, it was 88.67±4.27 minutes, i.e., an average reduction of 19.26%. This corresponds to a proportionally higher nutritional value of the product treated using the optimised regime. Data on the F_o and C_o values achieved during the sterilisation process can make a significant contribution to obtaining products with a better nutritional value through an optimised sterilisation process, without jeopardising product safety.