Abstract:The effects of high pressure homogenization (HPH) combined VC on the natural microorganisms, pH value, soluble solids content, color, total phenol and flavonoids in cloudy peach juice were studied. The aim of this study was to provide a theoretical basis for commercial application of HPH. The changes of the microorganisms and quality in cloudy peach juice with/without 0.15% Vc were evaluated after HPH at a pressure range of 0-190 MPa, a temperature range of 30 ℃, 45 ℃ and 60 ℃. The results showed that the total plate count, molds and yeasts reduced with the increment of the pressure of HPH in the peach juice. The increment of inlet temperature could significantly reduce microorganisms. No molds and yeasts were detected in the treated cloudy peach juice when the pressure of HPH was above 110 MPa with inlet temperature of 60 ℃. After addition of 0.15% VC to the cloudy peach juice, the pH value and soluble solid content were also not significantly changed by HPH. The color of cloudy peach juice was significantly improved by HPH with VC. HPH increased the L* and b* value of cloudy peach juice and decreased a* value. As compared with the sample without VC, the value of ΔE was significantly decreased after HPH, indicating HPH could better preserved the color of cloudy peach juice with VC. The total phenol and flavonoids were significantly increased in cloudy peach juice with addition of VC, which was 2-3 times than control sample. According to the study, it could be concluded that the treatment of HPH combined with VC could significantly reduce the microorganisms in peach juice, inhibit the browning and improve total phenol and flavonoids in cloudy peach juice.