Process optimization of spray drying of beetroot Juice.

Area of Science:

• Food Science and Technology
• Chemical Engineering
• Nutritional Science

Background:

• Beetroot (Beta vulgaris) is rich in betalains, potent antioxidants with various health benefits.
• Spray drying is a common method for preserving beetroot's bioactive compounds, but requires process optimization.
• Optimizing spray drying parameters is crucial for maximizing yield and quality of beetroot powder.

Purpose of the Study:

• To optimize the spray drying process for beetroot juice to produce high-quality beetroot powder.
• To determine the optimal feed flow rate, processing temperature, and maltodextrin concentration.
• To evaluate the impact of these parameters on packed bulk density, moisture content, and betalain content.

Main Methods:

• Response surface methodology (RSM) was employed to study the effects of key process variables.
• Variables investigated included feed flow rate (8-11 mL/min), processing temperature (140-160 °C), and maltodextrin concentration (20-30%).
• Packed bulk density, moisture content, and betalain content were measured to assess powder quality.

Main Results:

• Optimal spray drying conditions were determined as a feed flow rate of 10 mL/min, processing temperature of 149 °C, and 20% maltodextrin concentration.
• Predicted values at optimum conditions were 0.62 g/mL for packed bulk density, 6.12% for moisture content, and 33.84 mg/100 g for betalain content.
• Experimental results closely matched predicted values, validating the developed RSM models.

Conclusions:

• The study successfully optimized spray drying parameters for beetroot juice, yielding powder with desirable physical and chemical properties.
• The optimized process ensures high retention of betalain content and suitable packed bulk density.
• The validated RSM models provide a reliable tool for controlling beetroot powder quality during spray drying.