Abstract:

In the processing technology of carrot juice concentrate, pectinase dose affecting carrot juice yield and working parameters of triple effect vacuum flasher for concentrating carrot juice were optimized. The results showed that the carrot juice yield could be increased by 20% when treating crushed carrot pulp with 150 mg/kg of pectinase for 50 min at 50 ℃. The optimal working parameters of triple effect vacuum flasher were determined by orthogonal test as follows: concentration temperature 50 to 55 ℃, vacuum degree 9.33×104 to 10.0×104 Pa, steam pressure 7.5 ×104 to 8.0×104 MPa, and carrot juice flux 6.0× 103 to 6.5×103 L/h. When stored at not higher than －18 ℃, the pH value, and total acid and β-carotene contents of concentrated carrot juice had little changes.

Key words: carrot juice concentrate, carrot juice yield, vacuum concentrating, processing technology