Studying the effects of superchilling storage conditions on the microstructure and quality of chicken breast meat

This work aims to investigate the impact of superchilling conditions on the microstructure and quality of chicken breast meat. The chicken breast samples were partially frozen in an air blast freezer at −30 °C for 1 min and 10 min for microstructure and quality analyses, respectively, followed by storage under three different conditions (‒ 1.3 ± 0.5 °C; −1.6 ± 0.1 °C; ‒ 2.0 ± 0.1 °C) for 21 days. X-Ray microtomography coupled with a thermostated cell was used to image and quantify the evolution of the 3D microstructure throughout the storage period at four different analysis time-points (1, 7, 15, 21 days). Quality attributes such as drip loss, color, and pH was also assessed at the same analysis time-points. This novel approach provided detailed insights into the ice crystal location, distribution, and volume fraction within the samples. Results showed that the microstructure and quality were significantly impacted by storage conditions, with more pronounced changes observed under fluctuating temperature (‒ 1.3 ± 0.5 °C). Notably, ice volume fraction increased from 30% to approximately 37% in constant storage conditions, while fluctuating temperatures led to a decrease in ice volume fraction to around 26%. Drip loss remained stable the first fifteen days of storage before increasing by around 20% for constant temperatures but increased by 64% under fluctuating conditions by day 21. Color difference and pH evolution were also influenced by storage duration and temperature. A principal component analysis showed that drip loss and meat discoloration were strongly correlated to prolonged storage while the evolution of pH and ice volume fraction depended primarily on the specific superchilling temperatures applied. These findings emphasize the importance of precise temperature control during superchilling to maintain meat quality.

The novelty of this work lies in the application of X-ray microtomography to assess the impact of superchilling conditions on meat structure, providing a detailed insight into microstructural changes. This method offers a unique, non-destructive way to monitor quality attributes, offering valuable information for optimizing the design of the superchilling process and ensuring product quality.