Document Type : Original Paper

Authors

• Ali Ayaseh ¹
• Mohammad Alizadeh ²
• Mohsen Esmaiili ³
• Abbas Mehrdad ³
• Yousef Javadzadeh ⁴

¹ PhD. Student, Department of Food Science and Technology, Faculty of Agriculture, University of Urmia, Urmia Iran

² Associated Proessor, Department of Food Science and Technology, Faculty of Agriculture, University of Urmia, Urmia, Iran

³ Associated Professor, Department of Physical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran

⁴ Associated Professor, Department of Industrial Pharmacy, Faculty of Pharmacy, University of Medical science of Tabriz, Tabriz, Iran

Abstract

In this study carrot juice samples were sonicated according to a D-optimal design response surface with different treatment of sonication temperature (25, 37.5 and 50⁰C), sonication time (10, 20 and 30 min) and sonication power (350, 400w) at a constant frequency of 24 kHz. The results showed that ultrasound temperature (P<0.01), time (P<0.01) and interaction between time and temperature (P<0.01) significantly decreased the peroxidase enzyme activity of carrot juice samples and a prediction model obtained with high coefficients determination (R²=98%). Enzyme activity thermal treated juice processed at 90-88⁰C for 4 min was undetectable. Ultrasound time significantly decreased the L-value, a-value, b-value, and TCD _Blank (P<0.05) of carrot juice samples. Whereas ultrasound temperature significantly increased the a-value (P<0.01) and TCD _Blank (P<0.05) samples. The obtained results showed that, ultrasound treatment significantly decreased peroxidase enzyme activity due to cavitational effects and reduced color parameters degradation specially a-value of carrot juice. Thus in order to maintain the quality of processed carrot juice; ultrasound processing could be accompanied by additional measures such as exclusion of oxygen, refrigerated storage and the use of natural enzyme inhibitors.

Keywords

• Carrot juice
• Color parameters
• Peroxidase
• Sonication