Abstract:Chilled chicken is the primary form for raw chicken consumption. Temperature fluctuations often occur during cold chain storage and transportation, however, the impact of these fluctuations on chicken quality remains unclear. Chilled chicken was stored for varying durations under two temperature fluctuation ranges (0~4 ℃, 0~10 ℃), with constant storage temperatures (0, 4, and 10 ℃) as controls. The quality changes of chilled chicken during storage were determined by analyzing physicochemical indicators, including total volatile basic nitrogen (TVB-N), flavor, juice loss rate, water-holding capacity, texture, and thiobarbituric acid-reactive substances (TBARS), as well as microbial indicators such as total viable counts, Pseudomonas, Brochothrix thermosphacta, Enterobacter, and lactic acid bacteria. Low-field nuclear magnetic resonance and scanning electron microscopy were used to observe changes in internal moisture and tissue microstructure in chicken. The results showed that on the 8th day of storage, the TVB-N value of chilled chicken stored under fluctuating temperature (0~4 ℃, 0~10 ℃) was 1.12 and 1.34 times higher, respectively, than that of chicken stored at a constant 4 ℃. Additionally, the total viable counts were 1.90 and 3.95 times higher than those under constant 4 ℃ storage. Temperature fluctuations accelerated the reproduction of Pseudomonas, Brochothrix thermosphacta, and Enterobacter in chilled chicken, promoting the separation of chicken myofibrils, damaging tissue structure, and causing water migration from the interior to the surface of the chicken. This led to a significant increase in juice loss rate and a notable decrease in water-holding capacity, thereby accelerating the quality deterioration of chilled chicken.
