Hamza Bozkir and Taner Baysal
Ege University, Turkey
Munzur University, Turkey.
Posters & Accepted Abstracts: J Food Process Technol
Apple juices are rich high nutritional value due to involving minerals, vitamins, phenolic compounds and antioxidant substances. Concentration of apple juices reduces cost of storage, packaging and transport, moreover juice becomes microbiologically and chemically more stable. The principle of application of microwave heating is absorbing the microwaves by increasing the temperature as a result of vibrations and friction between the polar molecules and ionic polarization. Vacuum microwave heating provide volumetric heating and concentration carried out quickly at a short time. The objective of this study is produce concentrated apple juice with vacuum microwave evaporator and rotary evaporator and comparing the process conditions and quality parameters. Apple juice was concentrated by different power levels (334, 502, 668 W at 500 mbar vacuum) at MVE and rotary evaporator (500 mbar and 82 °C). HMF, color and evaporation rates at these conditions were detected. As concluded, evaporation rates were found as 5.43, 11.50, 14.37 gH2O/min and HMF values were found as 2.08, 1.81 and 1.65 mg/L respectively for the powers of 334, 501, 668 W. The evaporation rate and HMF were found as 4.33 gH2O/ min and 2.622 mg/L respectively for rotary evaporator. The total color differences were 1.70 for 334 W, 1.66 for 501 and 1.20 for 668 W. The lowest color difference, HMF value and the highest evaporation rate was found at the 668 W in comparison with rotary evaporator.
Hamza Bozkir has completed his undergraduate education (2008) and Master (2010) studies from Sakarya University, Turkey. He is Researcher Assistant in Food Engineering Departmant, Munzur University, Turkey. He is still continuing PhD education in Ege University, Graduate School of Natural and Applied Sciences, Food Engineering Section, Izmir, Turkey. He is working on food technology, especially microwave heating processing.