Progress 12/01/00 to 11/30/04
Outputs
The infrared heating system designed consisted of six far infrared heating elements, a waveguide, sample plate, along with data acquisition units. All of the IR heating elements were individually controlled to emit the desired spectral distribution. The waveguide was installed between the heating elements and the sample plate. The optical filter was chosen and installed such that it could deliver IR radiation to food component more specifically, to the desired spectral range. Inactivation of fungal spores of Aspergillus niger and Fusarium proliferatum in corn meal was investigated using selective IR heating by choosing suitable bandpass filters. The mechanism for the thermal death kinetics model using the selective heating concept for inactivation of fungal spores based on a dynamic temperature profile was also studied. The approach was consistent with the past work suggesting that the actual temperature of the pasteurized sample radiated by far infrared radiation
might be higher than that measured by the thermocouple. Model predictions of higher fungal spore temperature was validated by showing that pure dried fungal spores were heated 6C higher than pure corn meal after 300 sec of heating. Differential heating of fungal spores was validated by demonstrating that dry fungal spores were heated by up to 6C higher than pure corn meal after 300 sec of heating. An R2-value greater than 0.98 was observed between the model-predicted and measured survival ratios. The denaturation of protein components in the selective IR range also contributed to an additional increase in the degree of lethality of fungal spores, compared to model prediction. This concept has now being extended to inactivating pathogens on meat surfaces in the context of food safety. Mathematical modeling concepts developed for IR heating were modified to simulate the intermittent drying phenomenon of bananas. Modeling of heat and mass transfer was accomplished using a coupled set of
equations. The developed model was tested and validated for other drying systems, including batch drying. Excellent agreement of the simulated results with experimental data for stepwise as well as batch convective drying of banana samples indicate the validity of the procedure and its incorporation in the optimization of drying processes.
Impacts
The infrared system developed is becoming a key processing technique in selective heating of coatings that will have implications in the confectionery products. Because of its potential, the system is now being adapted for the inactivation of pathogens in dairy products (milk and cheese). Discussions are in progress to explore the possibilities of Listeria inactivation on meat, more specifically, turkey breast for in-package sterilization. The simulation models developed for IR heating was extended to model the heat and mass transfer phenomenon in other food systems.
Publications
- Ranjan, R,. Irudayaraj, J., Reddy, J., and Mujumdar, A. S. 2004. Finite element simulation of stepwise drying of bananas. J. Num. Heat Tr. Part A. 45(10):1-16.
|
Progress 01/01/03 to 12/31/03
Outputs
The infrared heating system designed consisted of six far infrared heating elements, a waveguide, sample plate, along with data acquisition units. All of the IR heating elements were, individually, controlled to emit the desired spectral distribution. The waveguide was installed between the heating elements and the sample plate. The optical filter was chosen and installed such that it could deliver IR radiation to food component more specifically, to the desired spectral range. Inactivation of fungal spores of Aspergillus niger and Fusarium proliferatum in corn meal was investigated using selective IR heating by choosing suitable bandpass filters. The mechanism for the thermal death kinetics model using the selective heating concept for inactivation of fungal spores based on a dynamic temperature profile was also studied. The approach was consistent with the past work suggesting that the actual temperature of the pasteurized sample radiated by far infrared radiation
might be higher than that measured by the thermocouple. Model predictions of higher fungal spore temperature was validated by showing that pure dried fungal spores were heated 6C higher than pure corn meal after 300 sec of heating. Differential heating of fungal spores was validated by demonstrating that dry fungal spores were heated by up to 6C higher than pure corn meal after 300 sec of heating. An R(2)-value greater than 0.98 was observed between the model-predicted and measured survival ratios. The denaturation of protein components in the selective IR range also contributed to an additional increase in the degree of lethality of fungal spores, compared to model prediction. This concept has now being extended to inactivating pathogens on meat surfaces in the context of food safety.
Impacts
The infrared system developed is becoming a key processing technique in selective heating of coatings that will have implications in the confectionery products. Because of its potential, the system is now being adapted for the inactivation of pathogens in dairy products (milk and cheese). Discussions are in progress to explore the possibilities of Listeria inactivation on meat, more specifically, turkey breast for in package sterilization. The experience gained from this research have been instrumental in initiating discussion on the inactivation of mycotoxin in almonds with Chapman University (California).
Publications
- Ranjan, R. and Irudayaraj, J. 2003. Unsteady -- state mass transfer in biological systems. Encyclopedia of Agriculture food and biological engineering. ISSN: 0-8247-0938-1., Marcel Dekker Inc. NY. 7 pp.
- Jun, S., and Irudayaraj, J. 2003. A dynamic fungal inactivation approach using selective infrared heating. Transactions of the ASAE 46(5):1407-1412.
- Jun, S. and Irudayaraj, J. 2003. An Integrated Dynamic model for Fungal Spore Inactivation by Selective Infrared Heating. Transactions of the ASAE. Accepted for Publication.
|
Progress 01/01/02 to 12/31/02
Outputs
A novel far infrared (FIR) heating system was designed and fabricated for selective heating of food powders such as soy protein and glucose. The incident FIR radiation could be controlled to provide electromagnetic radiations in the specific spectral regions using different optical filters. By choosing appropriate optical bandpass filters, the spectral manipulation of IR radiation concept can be applied for a range of materials. Inactivation of fungal spores of Aspergillus niger and Fusarium proliferatum in corn meal was investigated using selective IR heating method. The mechanism for the thermal death kinetics model using the selective heating concept for inactivation of fungal spores based on a dynamic temperature profile was also studied. The approach was consistent with the past work suggesting that the actual temperature of the pasteurized sample radiated by far infrared radiation might be higher than that measured by the thermocouple. Model predictions of
higher fungal spore temperature was validated by showing that pure dried fungal spores were heated 6C higher than pure corn meal after 300 sec of heating. The denaturation of protein band as a target spectral region of selective heating could also partially contribute to an additional increase in the lethality of fungal spores compared to model prediction.
Impacts
The process developed can be used for disinfestation. The infrared system is being examined for use in a confectionery process by industry personnel. Work is in progress to extend this to pasteurization of dairy products.
Publications
- Jun, S. and Irudayaraj, J. 2002. Selective far infrared heating system design and evaluation (PART I). Drying Technology - An International Journal. 21(1):51-67.
- Jun, S. and Irudayaraj, J. 2002. Selective far infrared heating system applications adn analysis (PART II). Drying Technology - An International Journal. 21(1):69-82.
- Ranjan, R., Irudayaraj, J., and Jun, S. 2001. Simulation of infrared drying process. Drying Technology - An International Journal. 20(2):363-379.
- Ranjan, R. , Irudayaraj, J., and Mahaffy, J. 2002. Modeling simultaneous heat and mass transfer using the control volume method. Journal of Numerical Heat Transfer. Part B, 41:1-15.
|
Progress 01/01/01 to 12/31/01
Outputs
The infrared heating system basically consisted of 6 FIR heating elements, waveguide, sample plate, and control units. All of the IR heating elements were, individually, controlled to be able to emit the desired spectral distribution. The waveguide was installed between the heating elements and the sample plate. The optical filter was chosen and installed such that it could deliver IR radiation to food component more specifically, in terms of the spectral range. Selective heating of soy protein over starch (glucose) was accomplished by using the optical filters. The spectral range of the optical filter chosen was suitable for C-H bond of protein domain to activate and absorb IR energy dominantly, as measured from the FTIR spectrometer. The result showed that soy protein was heated more than glucose by 6 degrees C, with the filter by selective heating. The effect of spectral manipulation on the radiative heating of food components was demonstrated using a novel IR
heating system. The incident IR radiation could be controlled to have a variety of spectral distributions corresponding to the filter options. Fungus disinfections (Aspergillus niger and Fusarium proliferatum) were accomplished using the selective heating technique. It is observed that the peak magnitude increased in the spectral range between 5.88 and 6.66 microns(amide II region) for infected corn meal, hypothesizing that the selective heating was able to denature the protein component relevant to the spore growth. Experiments indicate a 2 log reduction in 5 min, which is enhanced over the previous results reported by Hamanaka et al. (2001).
Impacts
A novel system was designed and constructed to heat food at different rates. The differential heating technique using the IR radiation is expected to meet a variety of requirements from food industry because uniform heating or coating of food mixtures can be accomplished. Has potential to address food quality and safety issues. Can be applied to process specialized products with specialized or sensitive coatings, enzyme inactivation, and rapid surface heating.
Publications
- No publications reported this period
|
|