Effect of Incubation, Enzymes and Thermal Pre-treatments on the Quality of Pumpkin JuiceHesham AE* and Manal FS
Food Technology Department, National Research Centre, 12622 Cairo, Egypt
- *Corresponding Author:
- Hesham AE
Food Technology Department
National Research Centre, 12622 Cairo, Egypt
E-mail: [email protected]
Received date: March 01, 2015; Accepted date: April 10, 2015; Published date: April 27, 2015
Citation: Hesham AE, Manal FS (2015) Effect of Incubation, Enzymes and Thermal Pre-treatments on the Quality of Pumpkin Juice. J Nutr Food Sci 5:371. doi: 10.4172/2155-9600.1000371
Copyright: © 2015 Hesham AE, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Incubating fresh pumpkin (Cucurbita pepo L.) vegetable slices treated with thermal pre-treatments and a commercial exogenous enzyme preparation cellulase and α-amylase produced a pumpkin juice. HPLC was also carried out to fractionate the major sugar component found in fresh and treated pumpkin juice. Sucrose was the major sugar of the pumpkin juice which hydrolysis during water and steam blanching and cellulase enzyme pretreatments to glucose and fructose. Results concluded that the incubated pumpkin have the lowest WIS and water content compared to the fresh pumpkin juice without treatment. No pectin-methyl-esterase (PME) activity was found in water, steam and enzymes pre-treatments of pumpkin juice compared with the fresh pumpkin juice without treatment. It was found that the yield was increased in water blanching, followed by cellulase addition and then steam blanching. The inhibitory effect of various thermal and enzymes pre-treatments based on a*-values measurements at their high time and maximum concentrations for pumpkin juice treated in the following decrease order steam blanching > microwave > water blanching > α-amylase enzyme > cellulase enzyme. This research proved that pumpkin can be used as a pumpkin juice with thermal and enzymes pre-treatments after incubated fresh pumpkin vegetable slices at 55°C for 3 hours.