Progress 10/01/10 to 09/30/15
Outputs
Target Audience:The target audiences are the U.S. food manufacturing industry (e.g., producers of food, consumer goods and equipment). Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?1) Research projects addressing Objective 1 provided training to 7 graduate students (6 PhD and 1 MS), 1 visiting scientist, and 1 post doctoral scholar. 2) Curriculum revisions undertaken to address Objective 2 provide upper division food science majors with hands on food processing laboratory experiences to master concepts presented in lecture courses. How have the results been disseminated to communities of interest?Prior to publication in peer-reviewed journals, research was presented at numerous national and international professional conferences, Departmental seminars, industry site visits (most notably Procter & Gamble), and informal conversations with perspective undergraduate and graduate students. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
1) The work by CA and NY stations provides extensive comparison between models based on transport equations and experimental data acquired by magnetic resonance imaging that allows optimization of oven performance by equipment manufacturers. 2) The work by CA and MD stations improve the stability of frozen entrees and sauces with respect to syneresis and viscosity. The combination of texture measurements and discrete noninvasive techniques was capable of providing insightful understanding of water distribution in a gel system. 3) Magnetic resonance imaging, as an experimental technique, provided a means to understand and characterize food systems that are designed for better delivery of bioactive compounds. 4) Collaborative research between CA and IL stations has aided to develop mathematical modeling as a predictive tool to reduce oil uptake and improve quality of fried foods. 5) Magnetic resonance imaging, as an experimental technique, is providing a means to understand, characterize, and optimize mixing systems for the food and consumer products industries. For instance, processors can optimize the length of a static mixer in a process line to ensure adequate mixing of dissimilar fluid streams. 6) A 2-unit food processing laboratory course was developed and successfully offered to 145 undergraduate food science majors (total) in Fall 2013 and Fall 2014. The course focused on processing and quality assurance exercises that prepare students for responsibilities in their professional lives. The curriculum revision was approved by IFT in 2014 in their 5-year assessment of the food science program.
Publications
- Type:
Journal Articles
Status:
Accepted
Year Published:
2015
Citation:
Mihailova, O., Lim, V., McCarthy, M., McCarthy, K., Bakalis, S. Laminar mixing in a SMX static mixer evaluated by Positron Emission Particle Tracking (PEPT) and Magnetic Resonance Imaging (MRI). Chemical Engineering Science
- Type:
Journal Articles
Status:
Accepted
Year Published:
2015
Citation:
Lim, V., Hobby, A.M., McCarthy, M.J., McCarthy, K.L. Laminar mixing of miscible fluids in a SMX static mixer evaluated by Magnetic Resonance Imaging (MRI). Chemical Engineering Science
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Progress 10/01/13 to 09/30/14
Outputs
Target Audience: The target audiences are the U.S. food manufacturing industry (e.g., producers of food, consumer goods and equipment). Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Objective 1: This work incorporates collaborative research efforts between University of California, Davis and University of Birmingham (UK) to combine two sophisticated experimental techniques (MRI) and Positron Emission Particle Tracking (PEPT) to visualize flow within the in-line static mixer. The project has provided training to a PhD graduate student. Objective 2: 80 upper division food science majors successfully completed the offering of the newly developed food processing laboratory course. How have the results been disseminated to communities of interest? Objective 1: The work has been presented at a professional meeting and the North American Mixing Forum: Mihailova O, Bakalis S, McCarthy K , Lim V, McCarthy M. 2014. Application of MRI and PEPT to study complex flow through an SMX mixer. 2014 IFT Annual Meeting, Institute of Food Technologists, New Orleans, LA. Abstract No. 028-24. McCarthy KL , Tozzi EJ, McCarthy MJ. 2014. Magnetic resonance imaging (MRI) to assess rheology and mixing in process applications. North American Mixing Forum: Mixing XXIV, Lake George, NY. June 22-27. Plenary Talk. What do you plan to do during the next reporting period to accomplish the goals? Objective 1: Complete and submit 2 manuscripts for publication in peer-reviewed journals.
Impacts
What was accomplished under these goals?
Objective 1: Magnetic resonance imaging, as an experimental technique, is providing a means to understand, characterize, and optimize mixing systems for the food and consumer products industries. Objective 2: A 2-unit food processing laboratory course was developed and successfully offered to 80 undergraduate food science majors. The course focused on processing and quality assurance exercises that prepare students for responsibilities in their professional lives.
Publications
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Progress 01/01/13 to 09/30/13
Outputs
Target Audience: The target audiences are the U.S. food manufacturing industry (e.g., producers of food, beverages and equipment). Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? The first study that focused on delivery of bioactive compound provided training to a postdoctoral scholar and visiting scientist from Thailand through one-on-one work with the PIs. The second study that focused on reducing oil uptake in chicken nuggets provided training to a doctoral student and post doctoral scholar through one-on-one work with the PIs. Samples were prepared by industry collaborators. How have the results been disseminated to communities of interest? Prior to publication in peer-reviewed journals, the work was presented at a professional meeting: Oztop, M.H., Bansal, H., McCarthy, M.J., McCarthy, K.L., Takhar, P. 2012. Water and fat distributions in methyl cellulose coated chicken nuggets. 2012 IFT Annual Meeting, Institute of Food Technologists, Las Vegas, NV. Abstract No. 077-157. Oztop, M.H., Wichchukit, S., McCarthy, M.J., McCarthy, K.L. 2012. Whey protein/alginate combination beads as bioactive carriers in a food sustained release system. 2012 IFT Annual Meeting, Institute of Food Technologists, Las Vegas, NV. Abstract No. 238-01. What do you plan to do during the next reporting period to accomplish the goals? During the next reporting period the goals/objective/expected output will focus on activities under Objective 2 for NC1023: Develop pedagogical methodologies for improved learning of food engineering principles. One of the goals of the NC-1023 committee is to improve students' learning of food processing and food engineering principles. Work during the next reporting period will focus on developing laboratory experiences that enhance and reinforce concepts presented in lecture courses that cover food processing and preservation. The target audience will be University students enrolled in the food science major.
Impacts
What was accomplished under these goals?
Magnetic resonance imaging, as an experimental technique, provided a means to understand and characterize food systems that are designed for better delivery of bioactive compounds. Collaborative research between California-Davis and University of Illinois, has aided to develop mathematical modeling as a predictive tool to reduce oil uptake and improve quality of fried foods.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Wichchukit, S., Oztop, H.M., McCarthy, M.J., McCarthy, K.L. 2013. Whey protein/alginate beads as carriers of a bioactive component. Food Hydrocolloids 33:66-73.
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Oztop, H. M., Bansal, H., Takhar, P. S., McCarthy, K. L., and McCarthy, M. J. 2014. Using multi-slice-multi-echo images with NMR relaxometry to assess water and fat distribution in coated chicken nuggets. LWT - Food Science and Technology 55:690-4.
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Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: Outputs for NC1023 Engineering for Food Safety and Quality, Objective 1. Advancing the fundamental science and application of technologies to ensure safety and improve quality of food products follow. Specifically, under Obj 1a. (Utilize innovative methods to characterize food materials), We report collaborative work between California - Davis and Kasetsart University (Thailand) in the area of designing and characterizing a sustained release system. Physical and mechanical properties of a sustained release system from whey protein/alginate beads in a viscous media mimicking a beverage were evaluated. Under Obj 1c. (Develop mathematical models to enhance understanding of, and, optimize food processes), Texas Tech (Takhar) and California-Davis/McCarthy are completing collaborative research to address modeling and characterizing fried food. The project goal was to reduce fat content in chicken nuggets. The relation between transport mechanisms and food biopolymers were addressed using three-scale balance laws and entropy inequality to develop multiscale fluid and heat transport equations for predicting moisture loss and oil uptake. Data acquired by magnetic resonance imaging is being used to validate and/or modify the model for chicken nuggets. PARTICIPANTS: California-Davis researchers Drs. K.L. McCarthy and M.J. McCarthy and PhD student M. Oztop completed work with Texas Tech researchers Dr. P. Takhar and PhD student H. Bansal. Samples were prepared by an industrial collaborator according to specifications given by Texas Tech researchers. Graduate student researchers M Oztop (UCD) and H Bansal (TTU) worked together on a daily basis to complete this challenging multistate project. TARGET AUDIENCES: The target audiences are the U.S. food processing industry (e.g., manufacturers of beverages) and equipment manufacturers (e.g., fryers). PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Obj. 1a) Techniques, such as magnetic resonance imaging, provide a means to understand and characterize food systems that are designed for better delivery of bioactive compounds. Research results will be useful in product development of beverages with bioactive compounds. A manuscript is currently under review in a peer-reviewed journal. A presentation at the 2012 Annual Institute of Food Technologists Meeting reported this work. Obj. 1c) For the collaborative research between California-Davis and Texas Tech stations, mathematical modeling will provide a predictive tool to reduce oil uptake and improve quality of fried foods. A presentation at the 2012 Annual Institute of Food Technologists Meeting reported this work.
Publications
- Rakesh, V., Datta, A.K., Walton, J.H., McCarthy, K.L., McCarthy, M.J. 2012. Microwave combination heating: Coupled electromagnetics-multiphase porous media modeling and MRI experimentation. AIChEJ 58(4):1262-78.
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Progress 01/01/11 to 12/31/11
Outputs
OUTPUTS: Outputs for NC1023 Engineering for Food Safety and Quality, Objective 1. Advancing the fundamental science and application of technologies to ensure safety and improve quality of food products follow. Specifically, under Obj 1a. (Utilize innovative methods to characterize food materials), a collaborative study between Maryland and California-Davis stations was completed. We examined the water distributions in hydrogels that were subjected to freeze thaw cycles. The intent was to provide information by several experimental techniques to better understand syneresis, relevant to the use of these gels in frozen foods. Under Obj 1c. (Develop mathematical models to enhance understanding of, and, optimize food processes), the California-Davis and Texas Tech stations have a collaborative project to validate mathematical models of water and fat distributions of chicken nuggets. Fat and moisture distributions obtained experimentally by magnetic resonance imaging (California-Davis station) will be incorporated into a multiscale fluid and heat transport model for predicting moisture loss, and oil uptake coupled with physico-chemical changes in foods (Texas Tech). PARTICIPANTS: Objective 1: California-Davis researchers Drs. K.L. McCarthy and M.J. McCarthy and PhD student M. Oztop are working with Texas Tech researchers Dr. P. Takhar and PhD student H. Bansal. Samples were prepared by an industrial collaborator according to specifications given by Texas Tech researchers. California-Davis researchers hosted a visit by Dr. Takhar to learn magnetic resonance imaging experimental protocol and data analysis. Future exchange between stations will be planned as necessary. TARGET AUDIENCES: The target audiences are the U.S. food processing industry (e.g., manufacturers of frozen foods) and equipment manufacturers (e.g., fryers). PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Obj. 1a) The long term goal of this work is to improve the stability of frozen entrees and sauces with respect to syneresis and viscosity. The combination of texture measurements and discrete noninvasive techniques was capable of providing insightful understanding of water distribution in a gel system. Research results will be useful in product development. A manuscript was published in a peer-reviewed journal. Obj. 1c) For the collaborative research between California-Davis and Texas Tech stations, mathematical modeling will provide a predictive tool to reduce oil uptake and improve quality of fried foods. An abstract has been submitted for presentation at the 2012 Annual Institute of Food Technologists Meeting.
Publications
- Rakesh V, Datta AK, Walton JH, McCarthy KL, McCarthy MJ. 2011. Microwave combination heating: Coupled electromagnetics-multiphase porous media modeling and MRI experimentation. AIChEJ (DOI: 10.1002/aic.12659)
- Williams PD, Oztop MH, McCarthy MJ, McCarthy KL, Lo YM. 2011. Characterization of water distribution in xanthan-curdlan hydrogel complex using Magnetic Resonance Imaging, Nuclear Magnetic Resonance relaxometry, rheology and Scanning Electron Microscopy. J Food Sci 76(6):E472-8
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Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: Outputs for NC1023 Engineering for Food Safety and Quality, Objective 1. Advancing the fundamental science and application of technologies to ensure safety and improve quality of food products follow. Specifically, under Obj 1a. (Utilize innovative methods to characterize food materials), a study was initiated and completed as collaboration work between Maryland and California stations. We examined the water distributions in hydrogels that were subjected to freeze thaw cycles. These hydrogels are prepared from xanthan, curdlan and a mixture of curdlan and xanthan. Magnetic resonance imaging (MRI) was used to assess the water distribution and changes in NMR relaxation times. The intent was to enhance information obtained by other experimental techniques to understand of these gels with respect to syneresis upon freeze-thaw relevant to their use in frozen foods. Under Obj 1c. (Develop mathematical models to enhance understanding of, and, optimize food processes), mechanistic models, combined with experimental evaluation, provide an approach to understand, design, and optimize food process operations. Magnetic resonance imaging (MRI) was used in this study to assess a mechanistic mathematical model based on full coupled electromagnetic-heat transfer model. The objective was to compare solutions for the prediction of internal temperature distributions in foods during combined convective and microwave heating to experimental temperature profiles. Cylindrical samples of a model food gel, Russet potato and rehydrated mashed potato were heated in a convection/microwave oven for specified times. For each sample, the internal temperature MR images were compared to spatial and temporal analytical predictions. Objective functions were defined and minimized for design and optimization. PARTICIPANTS: Objective 1: University of California, Davis researchers Drs. K.L. McCarthy and M.J. McCarthy complete collaborative efforts with Cornell University researchers Dr. A.Datta and PhD student V. Rakesh. Objective 1: University of California, Davis researchers Drs. K.L. McCarthy and M.J. McCarthy and PhD student M. Oztop worked with University of Maryland researchers Dr. Y. M. Lo and PhD student P. Williams. P. Williams was hosted at UC Davis to learn magnetic resonance imaging experimental protocol and data analysis. TARGET AUDIENCES: The target audiences are the U.S. food processing industry (e.g., manufacturers of frozen foods) and equipment manufacturers (e.g., convection and convection/microwave ovens). PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Obj. 1a) The long term goal of this work is to improve the stability of frozen entrees and sauces with respect to syneresis and viscosity. Research results will be used in product development. A manuscript has been prepared to submit for publication in a peer-reviewed journal. An abstract has been accepted for presentation at the 2011 Annual Institute of Food Technologists Meeting in June 2011. Obj. 1c) This work provides extensive comparison between models based on transport equations and experimental data acquired by magnetic resonance imaging. A journal article reporting this work has been accepted for publication in a peer reviewed journal; another article is under review.
Publications
- Rakesh V, Seo Y, Datta AK, McCarthy KL, McCarthy MJ. 2010. Heat transfer during microwave combination heating: Computational modeling and MRI experiments. AIChEJ 56(9):2468-2478.
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: Objective A: The Bostwick consistometer remains an integral part of assessing the consistency of tomato products in the factory. This work addresses the blending of tomato pastes, packed at different Bostwick readings, for use in tomato ketchup production. The objective of this work was to correlate in-line viscosity measurements of 12 Brix tomato concentrates to final product quality. Five blends of tomato concentrate were prepared by blending two pastes and diluting the mixture to a soluble solids level of 12 Brix In-line viscometry measurements at process temperature were made using magnetic resonance viscometry. The resulting Herschel-Bulkley parameters were used to evaluate an apparent viscosity at a characteristic shear rate. The apparent viscosity and Bostwick measurement for the blends were correlated based on a gravity current flow analysis. Ketchup was made from the tomato concentrate blends at three levels of natural tomato soluble solids (NTSS). The ketchup Bostwick measurement was then correlated to the ratio of viscosity to density taken to the 1/5 power of the 12 Brix tomato. Objective C: Mechanistic models, combined with experimental evaluation, provide an approach to understand, design, and optimize food process operations. Magnetic resonance imaging (MRI), as an experimental technique, is used extensively in both medical and engineering applications to measure and quantify transport processes. MR was used in this study to assess a mechanistic mathematical model based on Fourier's second law. The objective was to compare analytical solutions for the prediction of internal temperature distributions in foods during oven-based convective heating to experimental temperature measurements and determine at what point during the heating process a coupled heat and mass transport process should be considered. Cylindrical samples of a model food gel, Russet potato and rehydrated mashed potato were heated in a convection oven for specified times. For each sample, the internal temperature MR images were compared to spatial and temporal analytical predictions. PARTICIPANTS: Objective A: ConAgra Foods Research and Development researchers, T. Casey Garvey and Robert Sacher, worked with University of California, Davis researchers, Drs. K.L. McCarthy and M.J. McCarthy, on this industry-relevant problem. Objective C: University of California, Davis researchers Drs. K.L. McCarthy and M.J. McCarthy continue collaborative efforts with Cornell University researcher Dr. A.Datta and PhD student V. Rakesh. TARGET AUDIENCES: The target audiences are the U.S. food processing industry (e.g., manufacturers of tomato products) and equipment manufacturers (e.g., convection and convection/microwave ovens). PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Objective A: This work demonstrates that final product quality can be predicted from in-line viscosity measurements of an intermediate product. Objective C: This work provides extensive comparison between models based on transport equations and experimental data acquired by magnetic resonance imaging.
Publications
- McCarthy, K.L., McCarthy, M.J., Rakesh, V., A.K. Datta, A.K. 2010. Experimental and analytical temperature distributions during oven-based convection heating. J. Food Science 75(1):E66-E72.
- McCarthy, K.L., and M.J. McCarthy. 2009. Relationship between in-line viscosity and Bostwick measurement during ketchup production. J. Food Science 74(6): E291-E297.
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: Objective 1. Research activities continue in the development of in-line measurement of rheological properties using magnetic resonance imaging (MRI). This measurement technique combines measurements of a fluid velocity profile, obtained by MRI, and a simultaneous pressure drop to evaluate shear viscosity of fluids flowing in viscometric pipe flow. The objective of current work with a local tomato processor was to evaluate the rheological behavior of tomato concentrate blends and the ketchup produced from these blends. A number of ketchup samples were made from blends of two tomato pastes. The tomato pastes differed in their Bostwick measurement (a quality measurement used by the industry) at packing. In-line viscosity measurement of the tomato paste blends were related to final ketchup Bostwick measurements. The work was published in a peer-reviewed journal. Objective 2. 1H-NMR was used to study the effects of high pressure and thermal processing on membrane permeability and cell compartmentalization, important components to the texture of plant tissues. Destabilization effects on membranes exposed to high pressure were observed at 200 MPa under the present conditions, as indicated by T2 (relaxation time) measurements and SEM. In this study, T2 relaxation successfully identified different degrees of membrane damage based on T2 shift of the vacuolar component. The graduate student is currently reporting this work in her PhD dissertation. PARTICIPANTS: In addition to the project investigators, ConAgra Foods Research and Development researchers Drs. Robert Sacher and T. Casey Garvey worked on the project reported in Objective 1. These industry researchers were instrumental in identifying industry-relevant issues, providing samples from the processing lines, and reporting research results to their company. In addition to the project investigators, Drs. Diane Barrett (UC, Davis) and Henk Van As of Wageningen, The Netherlands guided the PhD student working on the project reported in Objective 2. The project fostered interaction between two premier agricultural universities. TARGET AUDIENCES: The target audience is U.S. food processors, especially the fruit and vegetable processing industries. Presentations were made specifically to Campbell Soup Co., ConAgra Foods, and California League of Food Processors regarding project work. PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Objective 1. Work performed by the CA station relates in-line viscosity measurement of tomato concentrate that is used in the production of ketchup to the final product Bostwick measurement, which is specified by the U.S. Standards for Grades of Tomato Catsup. The quantitative relationships allow in-line process control schemes to improve final product quality. Objective 2. Texture is one of the very important attributes of foods and in plant materials the crisp characteristic is given by the cellular turgor produced by the intact cell membranes (plasmalemma and tonoplast) acting on intact plant cell walls. Quantification of the cell structure changes that occur as a result of food processing will allow the comparison of different food processes on their impact on tissue quality attributes.
Publications
- McCarthy, K.L., Sacher, R.F., Garvey, T.C. 2008. Relationship between rheological behavior and Bostwick measurement during manufacture of ketchup. J. Texture Studies 39:4080-495.
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: Objective 1. Research activities continue in the development of in-line measurement of rheological properties using magnetic resonance imaging (MRI). This measurement technique combines measurements of a fluid velocity profile, obtained by MRI, and a simultaneous pressure drop to evaluate shear viscosity of fluids flowing in viscometric pipe flow. Recent activities evaluate the use and applicability of microfabricated radio frequency coils for viscosity measurements of fluid foods. Efforts in the past year have been focused on increasing food product range. In a second study under Objective 1, the goal of current work with a local tomato processor is to evaluate the rheological behavior of tomato concentrate blends and the ketchup produced from these blends. A number of ketchup samples were made from blends of two tomato pastes. The tomato pastes differed in their Bostwick measurement at packing. Ketchup was evaluated for loss of consistency during remanufacture and relative
contribution of each paste to final product consistency. Objective 2. The use of proton spin-spin NMR relaxation times to estimate internal quality of processing tomatoes was investigated. The study included firmness, maturity level and common defects. In general, there were statistically significant differences in the mean values of the spin-spin relaxation times at the P equals 0.05 level, yet these differences were small in magnitude. In addition correlations between spin-spin relaxation time and fruit firmness were poor. Objective 4. Development of magnetic resonance imaging as a sensor for internal fruit quality has focused on seed detection in mandarins. Chemometrics has been used to develop models for the determination of no seeds, one seed, two seeds and more than two seeds from a series of multiple congruent images. These activities support the citrus industry of California.
PARTICIPANTS: Kathryn L. McCarthy and Michael J. McCarthy are the principal investigators on the project. R.R. Milczarek was a PhD graduate student who worked on this project; stipend support for this student was provided by a grant from industry collaborators. Y.J. Choi was a postdoctoral researcher working on this project; financial support was provided by a grant from industry collaborators. S.S. Tu was an undergraduate researcher who worked on this project; hourly wages were provided by a grant from industry collaborators. T.C. Garvey and C.E. Fleck were industry collaborators from ConAgra Foods.
TARGET AUDIENCES: The target audiences are the tomato industry and the citrus industry of California and the United States.
Impacts
Objective 1. The miniaturization of the MRI-based in-line viscometer has promising applications to change the methods of process control and quality assurance in industrial settings. A second outcome for Objective 1 relates to the Bostwick consistometer measurement, which is the quality assurance test that is performed for consistency of tomato ketchup as specified by the U.S. Standards for Grades of Tomato Catsup. Work performed by the CA station relates the Bostwick measurement to off-line and in-line viscosity measurements in order to increase productivity and throughput at the factory level. Objective 2. Very low magnetic field strength based nuclear magnetic resonance sensors (<0.2 Tesla) are suitable for quality assurance laboratory testing and will provide more rapid turnaround of analytical testing. Objective 4. Development of internal quality sensors will complement existing external quality evaluation. This will assist U.S. fruit producers in differentiating
their product based on quality and better identify appropriate markets.
Publications
- Choi, Y.J., R.R. Milczarek, C.E. Fleck, T.C. Garvey, K.L. McCarthy and M.J. McCarthy. 2006. In-line monitoring of tomato concentrate physical properties during evaporation. Journal of Food Process Engineering. 29(6):6115-632.
- McCarthy, M.J. 2007. In: M.V. Koch, K.M. VandenBussche and R. W. Chrisman (eds). Micro Instrumentation, Wiley-VCH, Weinheim, pp. 241-245.
- Tu, S.S., Y.J. Choi, M.J. McCarthy and K.L. McCarthy. 2007. Tomato quality evaluation by peak force and NMR spin-spin relaxation time. Postharvest Biology and Technology 44(2):157-164.
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Progress 01/01/06 to 12/31/06
Outputs
Objective A: Research continues to develop in-line measurement of rheological properties using magnetic resonance imaging (MRI). This technique combines measurements of a fluid velocity profile, obtained by MRI, and a simultaneous pressure drop to evaluate shear viscosity of fluids flowing in viscometric pipe flow. Recent research evaluates the use and applicability of microfabricated radio frequency coils for viscosity measurements of fluid foods. The viscosity of fluid milk and milk-like products was measured using a nuclear magnetic resonance imaging based on microfabricated radio frequency coils coupled to in-line tubing with an inner diameter of 1.4 mm. Magnetic resonance based measurements from 2 to 15 1/s were obtained and were equivalent to off-line rotational rheometry. The device has promising applications in process control and quality assurance. Work continues with a local tomato processing to evaluate the rheological behavior of tomato concentrates.
Tomato concentrates were produced in a semi-batch evaporator at soluble solids content from 5.3 to 24 Brix. The apparent viscosity, yield stress and density were measured at 20C; in addition, the consistency of tomato concentrates was evaluated in a Bostwick consistometer at 20C (e.g., an extent of flow). The Bostwick measurement correlated well with the theoretical ratio of the apparent viscosity to density (R2 = 0.96); this relationship is based on flow as a gravity current, which quantifies horizontal flow due to gravity. For concentrates with yield stress values in the range of 60-200 Pa, the predicted extent of flow based on a slump analysis, used in the concrete industy, was within 2% of the Bostwick measurement. Objective D: A mathematical model was developed to predict the relationship between coating thickness and Casson parameters for milk chocolate during an enrobing process. The rheological properties for a number of milk chocolate samples were characterized using a
concentric cylinder viscometer according to the method recommended by the International Confectionery Association (IOCCC Analytical Method 46-2000). To assess the relationship between coating thickness and the Casson parameters, the chocolate enrobing process was modeled by an unsteady state mass balance. This approach is based on the draining of a viscous fluid down a vertical wall and results in a partial differential equation (pde). For a Casson fluid, the pde was solved numerically. The model predicted average coating thicknesses of the milk chocolate for a model system; the predicted values compared well with the experimental values obtained by dip coating.
Impacts
The impact of the three studies described above are (respectively): (1) the miniaturization of the MRI-based in-line viscometer has promising applications in process control and quality assurance, (2) quality control tests, such as the Bostwick consistometer and the slump test, can be related directly to measurable physical properties (e.g., apparent viscosity, yield stress and density, and (3) Casson parameters for molten chocolate can be used successfully to predict coating thickness as a function of formulation in a mathematical model based on drainage flow from a vertical surface.
Publications
- Karnjanolarn, R. and McCarthy, K.L. 2006. Rheology of different formulations of milk chocolate and the effect on coating thickness. J. Texture Studies 37(6):668-680.
- McCarthy, M.J., Choi, Y.J., Goloshevsky, A.G., DeRopp J.S., Collins, S.C., Walton, J.H. 2006. Measurement of fluid food viscosity using microfabricated radio frequency coils. J. Texture Studies 37(6):607-619.
- Milczarek, R.R. and McCarthy, K.L. 2006. Relationship between the Bostwick measurement and fluid properties. J. Texture Studies 37(6):640:654.
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Progress 01/01/05 to 12/31/05
Outputs
Objective A: In order to control a process and to assure product quality, ultrasonic Doppler velocimetry (UDV) is being used as a technique to monitor rheological properties in-line. Combined measurements of a fluid velocity profile, obtained by UDV, and simultaneous pressure drop permit the evaluation of rheological properties of fluids flowing in viscometric pipe flow. The current project utilized an ultrasonic velocity profile monitor to acquire velocity profiles and speed of sound measurements during processing of tomato concentrate in a semi-batch pilot scale evaporator. Simple shear viscosity were evaluated for tomato concentrates as a function of solids content (from 6 to 24 Brix) and tomato variety. Objective D: As part of the ongoing effort to implement in-line rheological measurements for process control, mathematical models are incorporated in a straight-forward graphical user interface (GUI) MatLab program. The structure and application of this program has
been published in open literature (Choi et al, 2005).
Impacts
Over 95% of the processing tomatoes in the U.S. are produced in California; the value of production in California is $670 million. A goal of processors is to remain competitive in a global economy. To do so, the California station is involved in characterizing properties, especially rheological properties, to ensure that the best materials are processed to whole peel/dice or to paste.
Publications
- Choi, Y.J., McCarthy, K.L., McCarthy, M.J. 2005. A MATLAB graphical user interface program for tomographic viscometer data processing. Computers and Electronics in Agriculture 47:59-67.
- McCarthy, M.J., Wang, L., and McCarthy, K.L. 2005. Ultrasound properties. IN Rao, M.A., Rizvi, S.S.H., Datta, A.K. (eds.) Engineering Properties of Foods, 3rd ed., Marcel Dekker, Inc., New York. pp. 567-609.
- Wang, Lu. 2005. In-line viscosity measurements based on ultrasonic Doppler velocimetry: effect of temperature gradients. Doctor of Philosophy Degree in Engineering, University of California, Davis, CA.
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