Use of Response Surface Methodology for Optimization of Clarified Mixed Apple and Carrot Juice Production

摘要

Response surface methodology was used to investigate the quality of clarified mixed apple and carrot juices using ultrafitration. Apple and carrot juices were blended at the ratio of l"-3, 1:1, and 3:1. A three-variable, three-level central compositedesign was employed where the independent variables were the blend ratio, temperature and average transmembrane pressure (ATP). With increasing temperature and pressure, flux linearly increased regardless of blending ratio. Blend juice with 75% apple showed the highest soluble sugar and total sugar content in apple and carrot blend juices. Soluble solid contents were more affected by blending ratio than temperature and ATP. Total sugar contents were greatly affected by temperature; increasing temperature led to higher total sugar content up to 25°C. Higher carrot ratio led to higher vitamin C content. In general, higher acidity was achieved by higher apple content and acidity was increased with increasing temperature. Turbidity increased for all samples as APT increased, with the blending ratio of 1:1 (apple:carrot) showing the highest turbidity. Viscosity was greatly changed in the blending ratio of 3:1 (apple:carrot) juice. The polynomial models developed by RSM were satisfactory to describe the relationships between the studied factors and the responses. Analytical optimization gave flux=0.216 L/m~2 - h, soluble solids=10.39°Brix, total sugar=71.32 mg/mL, vitamin C=315.18 mg%, acidity=7.78 mL, turbidity=0.017, and viscosity=1.44 cp, when using atemperature=44.97 deg C, ATP=113.57 kPa, and blend ratio=28.50%.