Microwave Assisted Freezing (MAF) was performed by applying constant microwave power and pulsed microwave power during freezing and results showed that the freezing time was not much affected by the MAF process. The application of microwaves during freezing process produced superior microstructure than the control sample; MAF significantly reduced the mean ice crystal size in apple and potato sample. Moreover, MAF samples exhibited a lower drip and texture loss compared to the control sample. The best result in terms of reduction in ice crystals size and retention of other quality parameters has been achieved with 667 W/kg pulsed microwave condition. As a conclusion, MAF resulted in higher quality frozen products.
This study is a part of ERANET “FREEZEWAVE” project coordinated by ONIRIS-GEPEA, Prof A. Le-BAIL and as a result, many researchers are investigating different aspects at the same time. A reduction of the size of ice crystal by ca 10 to 30% has been observed by the different partners of FREEZEWAVE on model food (tylose gel), meat and fish confirming the interest of the technology. The “NITOM” concept has been proposed (Nucleation Induced by Temperature Oscillation caused by Microwaves) to explain the improved microstructure; it is based on the impact of the fluctuating temperature caused by the pulsed energy emission on secondary nucleation during MAF freezing. A second concept called “NICMIW” (Nucleation Induced by Constant MIcroWaves power) based on constant power emission is supported by the impact of MW on hydrogen bonds between water molecules; this latter concept is less explanatory.
If you would like more information or would like to discuss this research further please contact Piyush Kumar Jha.
Each year EFFoST and Cargill present the student of the year award to six students and also give them the opportunity to showcase their research. In this article, Piyush Kumar Jha who won the 3rd prize for the PhD student of the year discusses his research. Currently, Piyush is a Post Doc fellow at ONIRIS-GEPEA (Nantes, France) still working with Prof LE-BAIL who was his PhD supervisor.