Experimental Hydrate Phase Equilibrium Data Relevant to Bitter Melon, Pineapple, and Grape Juice Concentration

Area of Science:

• Food Science and Technology
• Chemical Engineering
• Thermodynamics

Background:

• Rising energy costs pose a significant challenge to the fruit juice industry.
• Environmentally friendly and cost-effective methods are needed to maintain product quality during juice concentration.
• Hydrate-based concentration technology presents a promising alternative to conventional methods.

Purpose of the Study:

• To experimentally determine the hydrate phase equilibrium conditions for systems involving carbon dioxide (CO2) and three different fruit juices: grape, pineapple, and bitter melon.
• To investigate the inhibitory effects of these juices on gas hydrate formation.
• To estimate the energy requirements for hydrate-based juice concentration.

Main Methods:

• Isochoric pressure search method was employed to measure hydrate phase equilibrium.
• Experimental data were collected within temperature ranges of 272.6–282.3 K and pressure ranges of 1.17–3.85 MPa.
• Clausius-Clapeyron relations were utilized to estimate molar hydrate dissociation enthalpies.

Main Results:

• A decrease in water cut from 98.3% to 88.5 ± 2.53 wt% shifted hydrate phase equilibrium towards higher pressures and lower temperatures.
• All tested juices demonstrated inhibitory effects on gas hydrate formation.
• A dehydration ratio of 57% was achieved, indicating significant water removal.

Conclusions:

• Hydrate-based technology is a credible and energy-efficient alternative for fruit juice concentration.
• The investigated juices exhibit inhibitory effects, influencing the hydrate phase equilibrium conditions.
• This technology offers a sustainable approach to juice processing, addressing energy cost challenges.