bluuebunny/crossref_metadata_2025_split huggingface dataset:
DENSITY and COMPRESSIBILITY of SELECTED FOOD POWDERS MIXTURES1
Authors: CANOVAS GUSTAVO V. BARBOSA , MALAVE‐LOPEZ JOSE , PELEG MICHA 
Published: February 2007

ABSTRACTThe density and compressibility of various mixtures of granular and powdered sucrose, granular malic acid, soy protein and cornstarch, at 1:3, 1:1 and 3:1 were determined and compared to those of the pure components. Unless the particles were of similar size and properties (e.g., granular sucrose and malic acid) and density and/or compressibility could not be deduced from those of the pure ingredient, as a result of the formation of new bed structures. This was particularly the case in powders exposed to elevated relative humidity conditions, in this work aw= 0.65. Because compressibility can reflect changes in the bed structure as well as deformation of the particles themselves, no correlation could be found between loose bulk density and compressibility. Therefore, each mixture ought to be treated as a new powder the bulk properties of which are determined by their particular microstructure and the water moisture of their components.
ON‐LINE VISCOMETRY FOR PUREED BABY FOOD: CORRELATION of BOSTWICK CONSISTOMETER READINGS and APPARENT VISCOSITY DATA
Authors: VERCRUYSSE M.C.M. , STEFFE J. F. 
Published: February 2007

ABSTRACTThe relationship between Bostwick Consistometer (BC) readings and apparent viscosity was evaluated as an initial step in developing an on‐line viscometer for pureed baby food. Rheological properties of three baby food products (applesauce, carrots, and vegetable beef dinner) were investigated using a BC and a concentric cylinder viscometer in a temperature range from 73 to 92 C. Shear‐thinning, power law fluid behavior was found for all products. the overall correlation between results of the two methods of measurement, considered in terms of the Bostwick readings and apparent viscosity, was very poor. Developing an on‐line viscometer for pureed baby food products based on the relationship between Bostwick readings and apparent viscosity is not recommended.
POTASSIUM SORBATE PERMEABILITY of POLYSACCHARIDE FILMS: CHITOSAN, METHYLCELLULOSE and HYDROXYPROPYL METHYLCELLULOSE
Authors: VOJDANI FAKHRIEH , TORRES J. ANTONIO 
Published: February 2007

ABSTRACTEdible coatings controlling preservative migration from surface to food bulk could control surface microbial growth which is often the main cause of spoilage for many food products. In this paper we examine the potassium sorbate permeability behavior of chitosan, methyl cellulose and hydroxypropyl methyl cellulose based films. to gain an understanding of the permeation process, permeability determinations were done at 5, 24, 32 and 40°C. Permeability rates followed the Arrhenius activation energy model. A lack of breaking points in Arrhenius plots indicated that no morphological changes occur within these films in the 5 to 40°C temperature range. Activation energy values were found to be independent of film composition and were affected only by the solvent embedded in the film. This behavior was confirmed by analysis of the same permeability data using a modified Stokes‐Einstein equation.Methyl cellulose was the most promising diffusion barrier with a permeability constant of 3.4 and 1.4×10−8 (mg/s cm2) (cm)/(mg/cm3) at 24 and 5°C, respectively. Electron microscopy was used to examine the morphological characteristics of these films and showed they have no visible pores or channels at magnifications up to 10,000.
EFFECT of VOLUME CHANGE IN FOODS ON the TEMPERATURE and MOISTURE CONTENT PREDICTIONS of SIMULTANEOUS HEAT and MOISTURE TRANSFER MODELS
Authors: BALABAN M. 
Published: February 2007

ABSTRACTTemperature and moisture content predictions of two models of simultaneous heat and moisture transfer (SHMT) in foods with and without the assumption of volume change were compared. In the first model, thermophysical and transport parameters were kept constant. In the second model, these were taken as variable functions of temperature and moisture content. Comparison of the results of both models with and without shrinkage assumption showed that there can be significant differences in predicted moisture and temperature gradients, and average moisture contents and temperatures. Biot numbers for heat and mass transfer, and the extent of overall shrinkage with moisture loss are important factors affecting these differences. the predictions of the second model were compared to experimental drying data with shrinkage. the variable‐grid finite difference method can be used successfully to solve model equations involving volume changes.
ORIFICE DISCHARGE COEFFICIENTS FOR POWER‐LAW FLUIDS
Authors: SALAS‐VALERIO WALTER F. , STEFFE JAMES F. 
Published: February 2007

ABSTRACTOrifice discharge coefficients for non‐Newtonian (power‐law) fluids (5, 7.5 and 10% corn starch solutions) were measured using a closed end pipe with different orifice diameters. Results indicate that orifice discharge coefficients, found to be in the range of 0 – 0.7, are a function of the orifice diameter, fluid velocity in the orifice and the fluid rheological properties (consistency coefficient and flow behavior index). They increase with the fluid velocity, tend to be constant at high velocities and decrease when the consistency coefficient of the solution is increasing. Orifice discharge coefficients are presented as a function of the generalized Reynolds number.
ROBOTIC HIGH PRESSURE WATER JET CUTTING of CHUCK SLICES1
Authors: HEILAND W.K. , KONSTANCE R.P. , CRAIG J.C. 
Published: February 2007

ABSTRACTWith the objective of producing high quality and economical starting material for restructured beef products, the use of a high pressure water jet was investigated for excising objectionable material from slices of bone‐in beef chuck. From the limited number of tests conducted, best conditions for a clean, smooth cut were obtained with a water jet orifice diameter of 0.15 mm (0.006 in), a water pressure of 380 MPa (55,000 PSI), a slice thickness of 19 mm (3/4 in) and a linear cutting speed of 10.9 m/min (430 in/min). A preliminary cost comparison indicated that a fully automated line had a greate economic advantage over the manual method.
PRODUCTION PLANNING WHEN BATCHING IS PART of the MANUFACTURING SEQUENCE
Authors: NORBACK JOHN P. , RATTUNDE MARIA A.L. 
Published: February 2007

ABSTRACTBatching is a routine part of food production, even in many manufacturing sequences which have continuous components. Determining the correct number of batches to be produced in the face of continuous demand for final product and multiple demands on the batches from many products is a computationally complex problem. an organizational and computational scheme for tracking the impact of the batching decision is presented. the structure provides means for determining resource use patterns and for costing those patterns for a given production plan. the data necessary to drive this system are the costs, the batch formulation and yields and the other resources required by the product. the scheme is suited for electronic computation and can be rendered in a straightforward way on a microcomputer. an example illustrating how the data are organized is provided.
RICE PUFFING IN RELATION to ITS VARIETAL CHARACTERISTICS and PROCESSING CONDITIONS
Authors: CHANDRASEKHAR P.R. , CHATTOPADHYAY P.K. 
Published: February 2007

ABSTRACTThe effect of rice varietal characteristics, namely, length (L): breadth (B), ratio, amylose and protein contents and processing conditions namely, extent/degree of hydrothermal treatment, degree of milling and percentage of salt addition to rice, on puffing quality were studied in detail. the L:B ratio of varieties tested showed a positive correlation (r = 0.69) with expansion ratio (ER) of puffed rice produced. Total amylose and hot water insoluble amylose contents revealed a definite pattern of relationship, with ER showing predicted peaks at 28.5% total amylose (db) and 13.5% insoluble amylose (db) for highest ER. Protein content showed a negative relationship (r =−0.79) with ER. A new method for determining extent/degree of starch gelatinization, based on Brabender hot paste peak viscosity value (viscosity of 15% slurry retained at 95°C for 20 min.) was used in this study. Normal parboiled and pressure parboiled rice having 425 BU and 240 BU peak viscosities produced highest ER of 7.5 and 9.7% respectively. A 6% milling (minimum) and a 2% salt (NaCl/CaCl2) addition during preconditioning of rice resulted in maximum ER.
INACTIVATION OF ESCHERICHIA COLI IN SKIM MILK BY HIGH INTENSITY PULSED ELECTRIC FIELDS
Authors: MARTÍN O. , QIN B.L. , CHANG F.J. , BARBOSA‐CÁNOVAS G.V. , SWANSON B.G. 
Published: February 2007

ABSTRACT The inactivation of microorganisms is the most important function in the processing of milk and dairy products. Traditionally, this purpose is realized by thermal treatment, but heat produces alterations to flavor and taste in addition to nutrient loss. The high intensity pulsed electric field (PEF) treatment should be a good alternative to heat because demonstrations have shown PEF can reduce the Escherichia coli survival fraction in aqueous solutions and model foods. In this study, PEF treatment was found to inactivate E. coli in skim milk (inoculum 109 CFU/mL) at 15C. The microorganism inactivation satisfied Hülsheger's model following a first order kinetic for both the electric field intensity and number of pulses when skim milk inoculated with E. coli was treated in a static or continuous flow chamber. PEF treatment in a continuous system when the critical electric field (Ec) and minimum number of pulses (nmin) were 12.34 kV/cm and 2.7 at 30 kV/cm and 30 pulses (0.7–1.8 μs pulse width) inactivated more microorganisms than in a static system. It has also been proven that increasing the pulse duration increases the E. coli inactivation. The inactivation of E. coli using PEF is more limited in skim milk than in a buffer solution when exposed to similar treatment conditions of field intensity and number of pulses due to the complex composition of skim milk, its lower electrical resistivity and the presence of proteins.
RESIDENCE TIME DISTRIBUTION (RTD) AND GOODNESS OF MIXING (GM) DURING CO2‐INJECTION IN TWIN‐SCREW EXTRUSION PART II: GM STUDIES
Authors: SINGH BHAJMOHAN , RIZVI SYED S.H. 
Published: February 2007

ABSTRACTExperimental residence‐time distribution (RTD) characteristics of an extrusion process may be used to estimate the extent of mixing experienced in the extruder. Using earlier theories of laminar mixing and striation thickness reduction, a new approach to estimate efficacy of mixing of two phases in the mixing zone of the extruder is proposed. Predicting the time required to achieve complete mixing and comparing it with the minimum time (plug flow time) that the extrudate spends in the mixing zone gives a ratio that can be used to evaluate the adequacy of extruder operating conditions for good mixing of gas/fluid injection and extrudate. Twin‐screw extrusion of cornmeal with carbon dioxide injection were used to investigate the effect of CO2 injection pressure and extruder screw speeds on mixing. Lower CO2 injection pressures (25 bars) and lower screw speeds (150 rpm) were theoretically shown to enhance mixing. Scanning electron micrographs (SEMs) of experimental samples taken showed smaller and more uniform cell structures for those conditions which were predicted to favor better mixing.
SIMULATION OF THE EVAPORATIVE COOLING PROCESS FOR TORTILLAS
Authors: TAYLOR T.A. , HELDMAN D.R. , CHAO R.R. , KRAMER H.L. 
Published: February 2007

ABSTRACT A simulation model was developed to predict temperature, moisture content and water activity of evaporatively cooled tortillas. The overall model was based on three parts: (1) the predicted equilibrium moisture isotherm for the product, (2) a correlation model for predicting the saturated water vapor pressure for a given temperature, and (3) the energy and mass balances for simultaneous convective heat and moisture transfer between product and cooling air. The simulation model was verified with experimental data and was found to accurately describe the behavior of the tortilla cooling system. The model predicted the simultaneous decrease in temperature, moisture content, and water activity of the product exposed to varying simulated processing conditions. It was found that cooling air velocity and temperature had the primary effect on product cooling and moisture loss rates.
DEVELOPMENT OF A LABORATORY SCALE COMPUTERIZED TEST UNIT FOR THE SIMULATION OF DEEP BED FERMENTATION AND DRYING OF ROOIBOS TEA
Authors: JOUBERT ELIZABETH , STEENKAMP ZALDEUS , MÜLLER RIKUS 
Published: February 2007

ABSTRACTA test unit for the small‐scale fermentation and drying of rooibos tea was developed to simulate deep bed fermentation and drying of the tea in practice. The data acquisition and control system consisted of an AT type personal computer interfaced with the test unit by a plug‐in type AD/DA board. Set points such as temperature, relative humidity and velocity of the inlet air could be specified for eight sequential, variable time intervals. Good control of dry bulb temperature and velocity of the inlet air was obtained, taking into account the restrictions placed on the system by the hardware. The maximum air velocity that can be used with a bed depth of 50 mm, without formation of voids, was determined as 1.8 m/s. Precautions should be taken to ensure uniform air distribution and bed depth. Good quality tea was obtained after fermentation and drying in the test unit.
GLASS TRANSITION TEMPERATURE (Tg) AND WATER ACTIVITY (aw) OF DEHYDRATED APPLE PRODUCTS
Authors: WELTI‐CHANES JORGE , GUERRERO JOSE A. , BARCENAS MARIA E. , AGUILERA JOSE M. , VERGARA FIDEL , BARBOSA‐CANOVAS GUSTAVO V. 
Published: February 2007

ABSTRACT The onset glass transition temperature (Tgo) of Granny Smith apple products was evaluated as a function of drying conditions (air drying and freeze‐drying) and moisture and water activity (aw) levels. Tgo was determined in the 0–0.75 aw range, and it was found to have a maximum value at aw= 0 (Tgo= 4.5 ± 1.6C) for freeze‐dried apple and a minimum value at aw= 0.75 (Tgo= ‐81.4 ± 0.1C) for freeze‐dried apple juice. A linear relationship between Tgo and aw was obtained in all cases. Theoretical Tgo values at aw= 0 were calculated using these equations, and were within the range of 3.0C (freeze‐dried apple) and 10.5C (apple dehydrated at 30C). When Gordon and Taylor's linear model was applied to the experimental data of all the apple products, K values within the range 2.4 (freeze‐dried apple juice) and 3.6 (apple dehydrated at 60C), and the theoretical Tg of solids values at aw= 0 between the range ‐16.3C (freeze‐dried apple juice) and ‐1.9C (apple dehydrated at 60C) were obtained. No effect of the type of drying on the value of Tg was detected.
A METHOD FOR DETERMINING THE CONVECTIVE HEAT TRANSFER COEFFICIENT DURING IMMERSION FRYING
Authors: HUBBARD LYNN J. , FARKAS BRIAN E. 
Published: February 2007

ABSTRACTThe convective heat transfer coefficient is a useful parameter in characterizing heat flow across a fluid/solid interface when the fluid flow field is complex and solution of the coupled transport equations impractical. While convective heat transfer coefficient values for many unit operations have been tabulated, the boiling phase of immersion frying has not been quantified. The objective of this study was to develop a laboratory method for the measurement of the convective heat transfer coefficient during immersion frying. The method that was developed was applied to the immersion frying of potato cylinders at an oil temperature of 180C. The convective heat transfer coefficient was initially 300 W/m2K, it increased sharply to 1100 W/m2K, and gradually decreased to 300 W/m2K over the duration of the process. Use of this new method will allow the study of the effects of oil temperature, oil quality, product shape/size, and product quality on heat transfer coefficients.
MODELING THE TEMPERATURE EFFECT ON THE FLOW BEHAVIOR OF SWEET POTATO PUREE1
Authors: KYEREME MICHAEL , HALE SCOTT A. , FARKAS BRIAN E. 
Published: February 2007

ABSTRACTA study was conducted to investigate the effect of temperature on viscosity of sweet potato (SP) puree. Rheological data of the puree were measured using a Bohlin VOR Rheometer. Shear rates employed ranged from 0.01–921 s−1. Thermal scans were run at 15, 25, 40, 60, 75, and 90C. The puree exhibited “shear thinning” behavior with a yield stress value of 10 Pa at each temperature tested. The characteristic of the flow behavior of the puree was determined by fitting the experimental data to Herschel‐Bulkley, Casson and Modified Casson models. The model with the best fit was then used to represent the combined effect of shear rate and temperature on the apparent viscosity of SP puree in a model based upon the Modified Casson model. The model was validated using data for SP puree samples at 50C. Results showed that, within the experimental conditions used in this study, the model could adequately predict apparent viscosities of sweet potato puree processed at different temperatures.
LUMPED‐PARAMETER APPROACH FOR PREDICTION OF DRYING KINETICS IN FOODS
Authors: FONTAINE J. , RATTI C. 
Published: February 2007

ABSTRACTDrying kinetics of the product are the most important data required for the design and simulation of air dryers. This essential information can be obtained through simple lab‐scale experiments. Nevertheless, due to the uncertainty of the process, specially when dealing with biological materials, all the necessary data at different operating conditions are not usually available. On the other hand, drying kinetic models are either too simple to expect reasonably good predictions, or too complicated to be applied easily.The key assumptions of a previously developed lumped‐parameter model for air drying kinetics were revised to examine their application to biological materials. A short cut method has been developed to simulate kinetic curves from a minimum number of experimental data. A simple parameter study was carried out to detect the most important variables that affect the mass transfer Biot number in order to predict kinetics data safely. Experimental (hot air) drying curves for bananas, grapes and mushrooms were obtained in a lab scale dryer, at different air temperatures (50 to 70C) and air velocities (1 to 3 m/s). A comparison between experimental and predicted data was done for different operating conditions.
EFFECT OF INSOLUBLE PARTICLES UPON SOLID INCLUSION LEVELS IN ICE FORMED ON A SUBCOOLED STAINLESS STEEL SURFACE
Authors: CHEN PING , CHEN XIAO DONG , FREE KEVIN W. 
Published: February 2007

ABSTRACTThis study employed an insoluble solid particle, i.e. a potato starch used as an example, to investigate the impact of the concentration of such particles suspended in water (with solid loading of 5, 10, 20 and 30 wt%) upon the solid inclusion levels in ice layers formed on a sub‐cooled smooth stainless steel plate surface. The effects of ice growth rate, bulk concentration and suspension velocity on insoluble solid inclusion, i.e. potato starch mass fraction, in ice layer were studied. The experiments, where potato starch is added into aqueous sucrose solutions or the reverse where sucrose is added into starch suspension, were also carried out to investigated effect of the starch particles on sucrose inclusion in ice and effect of solute (sucrose) on starch particle inclusion in ice. It has been found that solid inclusion in ice increases with increasing bulk concentration and average ice growth rate, at constant solution and coolant velocities, and increasing suspension velocity can help pure ice formation. The average distribution coefficient of sucrose in ice layer formed from sucrose solution does not appear to be affected by the addition of potato starch. However, the average distribution coefficient of potato starch in ice layer formed from suspension is influenced by sucrose concentration quite significantly.
INFLUENCE OF FLOW REGIMES ON TEMPERATURE HETEROGENEITIES WITHIN A SCRAPED SURFACE HEAT EXCHANGER
Authors: DUMONT ERIC , VALLE DOMINIQUE DELLA , FAYOLLE FRANCINE , LEGRAND JACK 
Published: February 2007

ABSTRACTIn industrial applications, fluids processed in scraped surface heat exchangers often show large temperature heterogeneities at the exchanger outlet. Our study deals with the thermal evolution of model fluids, Newtonian and non‐Newtonian in heating or cooling conditions and allows us to link the phenomena of appearance and disappearance of temperature heterogeneities with the changes in the flow pattern within the exchanger. Based on literature data dedicated to scraped surface heat exchangers as well as to annular spaces without blades, we have shown that thermally homogeneous products can be obtained when Taylor vortices appear in the exchanger. Studies done on the exchanger with and without blades show that the thermal behavior is basically the same for both geometries but with a difference in critical Taylor numbers value for change in heat transfer regime. The presence of blades promotes the appearance of instabilities at lower values of generalized Taylor number (Tag= 10 with blades; Tag= 39 without blades). It shows as well, that the value of critical Taylor number in scraped surface heat exchanger closely depends upon the flow‐rate even for very low values for Reaxg (Reaxg < <1).
FLOW PROPERTIES OF MALT CONCENTRATE‐SWEETENED CONDENSED MILK MIXTURES
Authors: TEJINDER S. 
Published: February 2007

ABSTRACT The rheological characteristics of various malt extract concentrate‐sweetened condensed milk mixtures in the ratios of 50:50, 60:40, 70:30 and 80:20 (w/w) were studied at 30 to 80C, using a coaxial viscometer. The magnitudes of flow behavior index varied from 0.42–0.93. Experimental temperatures and concentrations of sweetened condensed milk considerably affected pseudoplasticity, consistency index and yield stress values of the mixtures. At 60 to 80C, the 60:40, 70:30 and 80:20 mixtures showed spectacularly higher flow behavior index values than those of the 50:50. The yield stress values increased with increasing temperature. The increases were considerably high in the 50:50 mixtures. The hulless barley malt concentrate‐sweetened condensed milk mixtures, however, were mildly non‐Newtonian and showed decreases in the values for yield stress with increasing temperatures. The activation energy values for flow behavior index and yield stress were negative in magnitudes, whereas those of consistency index were positive, which ranged from 1.6 to 15.0 Kcal/g mole.
PILOT PLANT FOR OSMOTIC DEHYDRATION OF FRUITS: DESIGN AND EVALUATION
Authors: VALDEZ‐FRAGOSO A. , MUJICA‐PAZ H. , GIROUX F. , WELTI‐CHANES J. 
Published: February 2007

ABSTRACTThis work proposes a pilot scale equipment for osmotic dehydration (OD) of apple cubes that consists of a novel agitation‐immersion device, a bag filter and a vacuum evaporator to conduct simultaneously the OD process, filtration and reconcentration of the osmotic solution (OS). The functional method analysis was used to design the pilot plant. Apple cubes (∼1 cm3) were dehydrated using a 60 ° Brix sucrose syrup OS at 50C and a syrup/fruit ratio of 5. OD was conducted either with or without reconcentration of the OS. During the OD process particles of fruit were eliminated from the OS by filtration and the OS concentration was kept at 60 ° Brix by reconcentration in the evaporator. A comparison of the dehydration parameters of apple cubes obtained at pilot scale to those obtained at laboratory scale was done to evaluate the performance of the pilot equipment. The results show that the proposed set‐up can be suitable for commercial production of osmodehydrated fruits.