In order to develop pre-digested anti-choking chicken protein supplements, an an oil-in-water (O/W) Pickering emulsion was prepared using chicken oil and chicken breast protein hydrolysate. The effects of high-speed shearing homogenization on the properties of the emulsion were explored, and carrageenan was added to the emulsion to prepare thermally induced emulsion gels. The results showed that the emulsion prepared by high-speed shearing at 50 ℃ at a shearing speed of 17000 r/min for 6 min had a small particle size, uniform droplet size distribution and good physical stability. The emulsion gel with 0.3% carrageenan showed a yield stress point (G’ = G’’) in the frequency range of 0.1 to 100.0 rad/s, indicating that a phase change occurred, and it could maintain good gel properties at fluctuating temperatures of 25–55 ℃, and had improved water holding capacity (WHC). The emulsion prepared by high-speed shear treatment at 17000 r/min for 6 min at 50 ℃ had the best properties. The Pickering emulsion gel with 0.3% carrageenan had the best stability and was easily transformed into a fluid state, so it could be suitable for the elderly to consume.

In order to study the effect of low-temperature and low-airflow cooling on the quality of chilled chicken, carcasses from cage-reared broilers were cooled at different temperatures (−10, −15 and −20 ℃) at a controlled airflow rate of 0.1 m/s immediately after being slaughtered at the age of 90 d, and those cooled in iced water at 4 ℃ were used as control. The cooling rate was determined and changes in carcass mass, color, water-holding capacity (WHC), soluble protein content, myofibril fragmentation index (MFI) and shear force were analyzed after cooling and storage at 4 ℃ for 24 h. The results showed that low-temperature air cooling reduced the central temperature of broiler carcass to 4 ℃ in 60 min. The cooking loss, centrifugal loss and MFI in the air-cooled group were significantly better than those in the iced water-cooled group (P < 0.05). The carcass mass loss, cooking loss, centrifugal loss and shear force of the −15 ℃ air-cooled group were significantly better than those of the −10 ℃ air-cooled group (P < 0.05), and the a* value, cooking loss and centrifugal loss were significantly better than those of the −20 ℃ air-cooled group (P < 0.05). In conclusion, cooling the carcass for 60 min at −15 ℃ and an airflow rate of 0.1 m/s can meet the requirements of fast cooling of the carcass, and improve the quality deterioration of broiler meat during cooling and storage.

In this work, we compared the effects of carbon dioxide (CO₂) stunning, electric shock and non-stunning (direct slaughter) on the meat quality of yellow-feathered broilers (90 days old). The results showed that the degree of carcass injury in the CO₂ stunning group was the smallest, the rigor mortis process of muscle was shortened, the amount of bleeding was increased, and the rate of pH decline was significantly faster than that in the other two groups (P < 0.05). At 45 min postmortem, the brightness value (L*), redness value (a*) and yellowness value (b*) of the CO₂ stunning group were significantly lower than those of the other two groups (P < 0.05), while a significant increase in L* was found at 24 h (P < 0.05). At 45 min postmortem, the water-holding capacity, tenderness and texture (springiness and chewiness) of the CO₂ stunning group were significantly better than those of the other groups (P < 0.05), whereas the water-holding capacity and texture were significantly poorer at 24 h (P < 0.05). At 24 h, the sensory scores for odor and texture of the electric shock and direct slaughter groups were significantly higher than those of the CO₂ stunning group (P < 0.05). Collectively, CO₂ stunning is not be recommended for the slaughter of yellow-feathered broilers, and It is recommended to further optimize the mode of electric shock.