Tentative application of Stirling cooler technology in butter churning process.

This study investigated the influencing factors of the Stirling refrigeration bench on the cooling and churning functions and applied the Stirling refrigeration technology to butter processing. Results showed that both refrigerant volume and mechanical vibration frequency have significant effects on the cooling effect. Optimal cooling effect was achieved for the refrigeration bench with 50 mL refrigerant volume and 12.5 Hz vibration frequency. The temperature of cold end decreased 34.5 ± 2.3 °C after 420 s of refrigeration. Given the parameters mentioned above, the fastest butter formation was achieved when the initial fat content in the cream was 25 %. The quality of the resulting butter is better than the resulting butter formed by using creams with 15 or 35 % initial fat contents. The results provide certain theoretical references for the application of the Stirling refrigeration technology to the butter processing industry. [ABSTRACT FROM AUTHOR]