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Watermelon juice concentration using ultrafiltration: Analysis of sugar and ascorbic acid
Chiranjit Bhattacharjee1, Vinod K Saxena1, Suman Dutta1
1Chemical Engineering Department, Indian Institute of Technology (Indian School of Mines), Dhanbad, India.
Ultrafiltration of watermelon juice using a 5-kDa polyethersulfone membrane concentrated soluble solids effectively but reduced ascorbic acid. Cake layer formation was identified as the primary cause of membrane fouling during this process.
Area of Science:
- Food Science
- Chemical Engineering
- Membrane Technology
Background:
- Watermelon juice is a nutritious beverage rich in vitamins and antioxidants.
- Ultrafiltration is a membrane separation process used for concentrating food products.
- Polyethersulfone membranes offer good selectivity and flux for juice processing.
Purpose of the Study:
- To investigate the concentration of raw watermelon juice using ultrafiltration.
- To evaluate the impact of a 5-kDa polyethersulfone membrane on juice properties.
- To identify the main factors contributing to membrane fouling.
Main Methods:
- Laboratory-scale flat-plate ultrafiltration system.
- Polyethersulfone membranes with a 5-kDa molecular weight cutoff.
- Transmembrane pressures ranging from 100 to 300 kPa.
Main Results:
- High concentration of total soluble solids in the permeate was achieved.
- Ascorbic acid content in the permeate was lower compared to the original juice.
- Flux decay analysis indicated cake layer formation as the dominant fouling mechanism.
Conclusions:
- Ultrafiltration is effective for concentrating soluble solids in watermelon juice.
- Membrane fouling, primarily due to cake layer formation, requires further investigation for process optimization.
- Further research is needed to mitigate ascorbic acid loss during ultrafiltration.
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