bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of Positron‐Emission Particle Tracking (PEPT) Technique for Velocity Measurements in Model Food Fluids
Authors: BAKALIS S. , COX P. W. , WANG‐NOLAN W. , PARKER D. , RYER P. J. F
Published: July 2006

ABSTRACT Positron‐emission particle tracking (PEPT) is a method of following particles in opaque fluids inside metal equipment. Comparison of experimental and theoretical velocity distributions obtained in aluminum pipes indicated that PEPT can be used to measure velocity distributions in viscous fluids for conditions of relevance to the food industry. Velocities were also measured for a fluid containing starch particles using 2 tracers having diameters of 600 and 240 μm. Velocity profiles were not significantly different, but the smaller tracer passed closer to the flow boundaries. PEPT was also used to quantify the effect of headspace on the velocity distributions of rotating cans containing soup. While in fully filled cans, fluid moved in circular motion, addition of air altered this, resulting in D‐shape velocity contours.
Development of a Chemically Defined Medium for Growth of Bifidobacterium animalis
Authors: Kongo J. M. , Gomes A. M. P. , Malcata F. X.
Published: July 2006

ABSTRACT The growth of Bifidobacterium animalis was tested, under batch and continuous culture conditions, for dependence upon specific nitrogen compounds. The addition of nitrogen bases (adenine, xantine, and guanine) to the medium containing acid‐hydrolyzed casein significantly affected the growth of B. animalis, whereas no significant growth was reported when those bases were added to the medium containing only free amino acids; B. animalis was characterized by a μmax of 0.16/h when growth took place in PROLAB medium containing lactose and nitrogenous bases. Our study is potentially important toward design of improved infant milk formulations for healthy newborns.
Comparison of the Real‐time Microrespirometer and Aerobic Plate Count Methods for Determination of Microbial Quality in Ground Beef
Authors: LI X. , HSIEH Y. H. P.
Published: July 2006

ABSTRACT Real‐time microrespirometer measurements were compared with the aerobic plate count (APC) method to assess microbial quality of ground beef stored at 4°C and 7°C with and without previous freezing. The samples were monitored daily for CO2 evolution rate (CER) using a microrespirometer, APC, and were evaluated for color and odor changes by a sensory panel. The CER was highly correlated with the APC for all storage conditions (r2 = 0.787 to 0.952). The onset of meat spoilage was more closely associated with a specific CER value (>25 μL/h/g) than APC. The new method was found to be more accurate in predicting meat spoilage, especially for previously frozen samples.
Bioactive Packaging Materials from Edible Chitosan Polymer—Antimicrobial Activity Assessment on Dairy‐Related Contaminants
Authors: COMA V. , DESCHAMPS A. , MARTIAL‐GROS A.
Published: July 2006

ABSTRACT The inhibitory activity of chitosan‐based edible coatings was assessed against 2 food pathogens (Staphylococcus aureus and Listeria monocytogenes) and 1 strain involved in food alteration (Pseudomonas aeruginosa) on model agar medium and on a real cheese food product. Colony counting and epifluorescence microscopy methods were conducted, and the results show a nonsignificant influence of the components of the food matrix in the protection of the microbial population against chitosan activity. Numeration on model agar medium showed 100% inhibition of the development of selected Gram‐positive bacteria and 77% inhibition on Pseudomonas growth. Chitosan is thought to act through binding to the cytoplasmic membrane surface, and it is possible that the outer membrane protects the Gram‐negative cells. Moreover, epifluorescence microscopic results showed a possible chitosan action during a short time duration on the synthesis of nucleic acids and especially on the relative proportion of RNA compared with DNA. This impact was followed by an adaptative mechanism of the cells. Edible chitosan coating could thus be used to increase the microbial lag phase while decreasing the maximum density of selected microorganisms and could have potential application for dairy products preservation.
Lethal and Sublethal Action of Acetic Acid on Salmonella In Vitro and on Cut Surfaces of Apple Slices
Authors: LIAO C. H. , SHOLLENBERGER L. M. , PHILLIPS J. G.
Published: July 2006

ABSTRACT Antimicrobial action of acetic acid (AA) on Salmonella as affected by acid concentration, exposure time, culture age, and bacterial strains was investigated. Relative susceptibility of 6 Salmonella serovars to AA action was in the following order: S. bareilly > S. typhimurium > S. montevideo > S. poona > S. mbandaka > S. stanley. The stationary‐phase cells of S. mbandaka were 100‐fold more resistant to AA action than the log‐phase cells. A mixture of Salmonella strains at a specified physiological stage should be used when testing the efficacy of the sanitizer treatment. Washing apple disks with NaOCl, H2O2, AA, or Na3P04 greatly reduced the number of Salmonella and 30% to 40% of cells that survived were injured. Washing with a mixture of AA and H2O2 was the most effective in removing Salmonella from apple disks.
Temperature Profiles Within Milk after Heating in a Continuous‐flow Tubular Microwave System Operating at 915 MHz
Authors: Coronel P. , Simunovic J. , Sandeep K.P.
Published: July 2006

ABSTRACT: Milk with different fat contents (0, 1, 2, 4%, and chocolate milk) were heated in a specially designed continuous‐flow microwave applicator operating at 915 MHz. The nominal power was 5 kW and the flow rates were 2.0 and 3.0 L/min to attain laminar flow. Temperature profiles at the exit of the applicator were measured. The results showed that the average increases in temperature were similar to one another, being 42 °C at 2.0 L/ min and 29 °C at 3.0 L/min. Differences between the lowest and highest temperatures were 3.7 and 3.0 °C, respectively. The temperature profiles illustrated that slightly higher temperatures were achieved within segments flowing close to the center of the tube.
Changes in the Physicochemical Properties of Wheat‐ and Soy‐containing Breads During Storage as Studied by Thermal Analyses
Authors: Vittadini E. , Vodovotz Y.
Published: July 2006

ABSTRACT: Adding soy ingredients to baked products influences textural and sensorial properties. The changes in physical properties of bread modified with soy flour during 7‐d storage at ambient temperature were investigated using thermoanalytical techniques (differential scanning calorimetry and dynamic mechanical analysis). An increase in loaf density, moisture content, and FW content, and a decrease in amylopectin recrystallization were observed with increased addition of soy flour. Addition of soy shifted the main thermal transition (0 °C, mainly due to ice melting) to slightly lower temperatures (both in differential scanning calorimetry and dynamic mechanical analysis analysis) and decreased its temperature range (increased homogeneity). These observations suggest a role for soy in modulating bread staling.
Observation of the Structure, Moisture Distribution, and Oil Distribution in the Coating of Tempura by NMR Micro Imaging
Authors: Horigane A.K. , Motoi H. , Irie K. , Yoshida M.
Published: July 2006

ABSTRACT: The 3‐layered fine structure of the coating of the Japanese oil‐fried battered food, tempura, was observed by nuclear magnetic resonance micro imaging. The porosity of the intermediate layer was correlated to the moisture content of the batter. Chemical shift imaging, which gave moisture distribution and oil distribution images, revealed the changes in the coating after cooking. The oil was detected to a depth of only 1 mm in the outer layer immediately after frying, and its distribution slightly expanded in the surface layer with time after frying. Water quickly transferred from bean curd (tofu) as 1 ingredient, to the coating along the porous network wall within 25 min after frying.
Determination of the Most Bioactive Phenolic Compounds from Rosemary Against Listeria Monocytogenes: Influence of Concentration, pH, and NaCl
Authors: Campo J. Del , Nguyen‐The C. , Sergent M. , Amiot M.J.
Published: July 2006

ABSTRACT: The anti‐Listeria monocytogenes effects of 8 phenolic compounds, carnosol, carnosic acid, 12‐methoxy carnosic, ferulic and caffeic acid, rosmarinic acid, luteolin and luteolin‐7‐glucoside were evaluated with a Plackett and Burman design in mixtures mimicking the phenolic composition of rosemary extract without essential oils. At 30°C carnosic acid was the most efficient compound during 24 h, whereas luteolin became more active after 72 h. The antibacterial effect of pure carnosic acid was modeled under a range of different pH and NaCl concentration, using a Doehlert design. Under moderately acidified conditions, carnosic acid displayed a bactericidal effect at low concentration (5.5 μg/ml). Its activity was not greatly influenced by NaCl.
Effects of Freezing on Quality of Cold‐smoked Salmon Based on the Measurements of Physiochemical Characteristics
Authors: Rørå A.M.B. , Einen O.
Published: July 2006

ABSTRACT: How the quality of cold‐smoked Atlantic salmon (Salmo salar) is affected by freezing the raw fish as whole fish, as gutted fish, and as fillets before smoking, and by freezing the finished product after smoking was studied. Freezing before smoking resulted in increased product yield and water content, but softer texture and increased K‐value. Freezing reduced the content of astaxanthin but increased the lightness and the color intensity of the flesh. Gaping increased when the fish was frozen as fillets before smoking. Freezing only after smoking led to fewer changes in quality than freezing before smoking, whereas refreezing the finished products had little additional effect on quality.
Dual Fortification of Salt with Iodine and Encapsulated Iron Compounds: Stability and Acceptability Testing in Morocco and Côte d'Ivoire
Authors: Wegmüller R. , Zimmermann M.B. , Hurrell R.F.
Published: July 2006

ABSTRACT: The stability of local salt dual fortified with iodine and 19 iron compounds (encapsulated compared to nonencapsulated sulfate, fumarate, pyrophosphate, and elemental iron) was tested in Morocco and Côte d'Ivoire. Color and iodine content were measured after storage for 1, 2, 4, and 6 mo. Color acceptability was judged by standardized interviews. For most compounds, encapsulation did not protect against adverse sensory changes and iodine losses. However, 2 forms of ferric pyrophosphate, 1 small particle size (approximately 2.5 μm) and 1 micronized (approximately 0.5 μm), performed well and be useful in salt fortification. Improvements in current encapsulation techniques are needed to allow encapsulated iron to be used in salt fortification.
Ascorbic Acid Fortification Reduces Anthocyanins in Extruded Blueberry‐Corn Cereals
Authors: Chaovanalikit A. , Dougherty M.P. , Camire M.E. , Briggs J.
Published: July 2006

ABSTRACT: Corn meal was mixed with ascorbic acid (0%, 0.1%, and 1%, wt/wt) and sucrose (15%) or lowbush blueberry concentrate (17%), and twin‐screw extruded to produce ready‐to‐eat breakfast cereals. Consumers evaluated selected samples using just‐right scales. Extrusion decreased anthocyanins in blueberry cereals; ascorbic acid was retained better in cereals containing blueberry concentrate than in the sweetened corn cereals. Blueberry concentrate decreased expansion ratio and increased bulk density. Based on sensory scores, blueberry extrudates with 0.1% ascorbic acid could be acceptable if sweetness is increased.
Effect of K‐Casein Deglycosylation on the Acid Coagulability of Milk
Authors: Cases E. , Vidal V. , Cuq J.L.
Published: July 2006

ABSTRACT: The relationship between the content of N‐acetylneuraminic acid residues of micellar K‐casein and acid coagulability of milk was investigated. At 30 °C, partial deglycosylation of micellar K‐casein does not significantly affect the content of micellar proteins, micellar surface charge, and micellar solvation. Casein micelles modified by the release of part of the N‐acetylneuraminic acid residues showed a shorter acid gelation time, a higher rate of gel strengthening, and a higher final firmness. This enhancement in the gelation ability of the neuraminidase‐treated casein micelles of milk should appear as the result of increase in number of hydrophobic sites on the surface of casein micelle due to enzymatic deglycosylation of micellar K‐casein.
Isolation of an Angiotensin Converting Enzyme Inhibitory Peptide from Irradiated Bovine Blood Plasma Protein Hydrolysates
Authors: Lee S.H. , Song K.B.
Published: July 2006

ABSTRACT: An angiotensin converting enzyme (ACE) inhibitory peptide was isolated and purified from the hydrolysates of the irradiated bovine blood plasma protein. Blood plasma protein was irradiated at 10 kGy to eliminate microbial contamination and was enzymatically hydrolyzed using several commercial proteases: Alcalase, Esperase, and Flavourzyne. An ACE inhibitory peptide was isolated using membrane filtration, gel permeation chromatography, normal phase and reverse phase high‐performance liquid chromatography. The purified ACE inhibitory peptide was identified to be a tripeptide, His‐Pro‐Tyr, having IC50 value of 1.68 μM.
A Quasi‐Chemical Kinetics Model for the Growth and Death of Staphylococcus aureus in Intermediate Moisture Bread
Authors: TAUB I.A. , Feeherry F.E. , Ross E.W. , Kustin K. , Doona C.J.
Published: July 2006

ABSTRACT: The “quasi‐chemical” kinetics model accounts for all 4 phases of the microbial lifecycle based on a proposed series of chemical rate equations. The model fits continuous growth‐death kinetics for Staphylococcus aureus in intermediate moisture bread in various conditions of water activity, pH, and temperature. Growth rates evaluated using the quasi‐chemical model are compared with values obtained with the Gompertz model. Kinetics data obtained with the quasi‐chemical model are integrated with a probabilistic approach to estimate the boundary between growth and no‐growth conditions. Continuous modeling of microbial growth/death kinetics in actual foods advances predictive modeling that conventionally separates growth and death models.
Characterization of the β‐Glucosidase Activity Produced by Enological Strains of Non‐Saccharomyces Yeasts
Authors: Cordero Otero R. R. , Ubeda Iranzo J. F. , Briones‐Perez A. I. , Potgieter N. , Villena M. A. , Pretorius I. S. , Rensburg P. van
Published: July 2006

ABSTRACT: The β‐glucosidase activities of 20 wine‐related non‐Saccharomyces yeasts were quantified, characterized, and assessed for their efficiency in releasing aroma‐enhancing compounds during the winemaking process. Of these enzymatic activities, the β‐glucosidase activity of Debaryomyces pseudopolymorphus revealed the most suitable combination of properties in terms of functionality at wine pH, resistance to wine‐associated inhibitory compounds (glucose, ethanol, and sulfur dioxide), high substrate affinity, and large aglycone‐substrate recognition. Its potential as a wine aroma‐enhancing enzyme was confirmed by the significantly increasing concentrations of free volatiles (citronellol, nerol, and geraniol) during the fermentation of Chardonnay juice inoculated with both D. pseudopolymorphus and a widely used commercial starter culture strain of Saccharomyces cerevisiae, VIN13.
Sarcoplasmic Reticulum Ca2+‐ATPase and Cytochrome Oxidase as Indicators of Frozen Storage in Cod (Gadus morhua)
Authors: Godiksen H. , Hyldig G. , Jessen R
Published: July 2006

ABSTRACT: Activities of 2 membrane‐bound enzymes, Ca2+‐ATPase from the sarcoplasmic reticulum and cytochrome oxidase from the inner mitochondria membrane, were measured during frozen storage of cod. Enzyme activities were higher in cod muscle samples frozen at −30°C than at −20°C. Freezing‐induced activation of both enzymes was observed and the activation was amplified by ice storage prior to freezing. Sensory evaluation conducted at 9 mo of frozen storage showed differences between the sensory properties of cod frozen immediately after catch and frozen after 3 d of storage on ice. These results indicated that the enzymes might be useful as indicators of quality changes by frozen storage.
Pink Color Defect in Poultry White Meat as Affected by Endogenous Conditions
Authors: Holownia K. , Chinnan M.S. , Reynolds A.E.
Published: July 2006

ABSTRACT The pinking defect in cooked, uncured meat has been a problem in the poultry industry for nearly 40 years. Through the years, analyses of data revealed various processing factors that seem to influence the specific biochemical conditions (pH, redox potential, denaturation, reacting ligands) of the meat that are related to the chemical state of the pigments in cooked meat, their structure, and reactivity. This review addresses endogenous conditions that affect the pigments’ reactivity, and research studies conducted on in situ conditions resulting in pinking in cooked meat. Future studies could be devised for understanding mechanisms leading to developing processes for reduction/elimination of the pink defect in cooked white poultry meat.
Bioavailability of Eicosapentaenoic and Docosahexaenoic n‐3 Polyunsaturated Fatty Acids in Salmon Patties Compared with Capsules
Authors: Maki K.C. , Davidson M.H. , Dicklin M.R. , Ingram K.A. , Cyrowski M. , Umporowicz D.M. , Bell M. , Elliott J.G.
Published: July 2006

ABSTRACT This sequential treatment trial compared the bioavailability of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from salmon patties fortified with fish oil (DHA:EPA ratio = 1.8, total DHA + EPA about 2.2 g), unfortified salmon patties (DHA:EPA ratio = 1.9, total DHA + EPA about 1.1 g), and fish oil capsules (DHA:EPA ratio = 1.6, total DHA + EPA = 500 mg) in healthy older adults. Fortified salmon patties produced a significantly higher mean incremental area under the curve (AUCfasting‐9 h) than unfortified patties for plasma EPA (37.6 in contrast to 12.9 μg·h/mL, p= 0.017), for plasma DHA (103.7 in contrast to 40.8 μg·h/mL, p= 0.035) and for plasma EPA + DHA (141.2 in contrast to 53.7 μg·h/mL, p= 0.031). Plasma EPA and DHA responses were larger with the fortified than the unfortified patties, indicating that fish oil incorporated into the salmon patties was bioavailable.
Quality and Shelf Life of Duck Liver Pâté as Influenced by Dietary Supplementation with α‐Tocopheryl Acetate and Various Fat Sources
Authors: Russell E.A. , Lynch A. , Lynch P.B. , Kerry J.P.
Published: July 2006

ABSTRACT Duck liver pâté is highly susceptible to quality deterioration, particularly from lipid oxidation, because of its composition and the processes used in its manufacture. This study was aimed at evaluating the effectiveness of supranutritional amounts of α‐tocopheryl acetate and dietary oils fed to ducks on the oxidative and color stability of duck liver pâté. Pâté was made from livers of ducks fed α‐tocopheryl acetate with tallow, or olive, sunflower, or linseed oil. Feeding tallow produced pâté with higher saturated fats. α‐Tocopheryl acetate supplementation delayed lipid oxidation and improved color stability of duck liver pâté. Dietary linseed oil induced the most lipid oxidation and the darkest color in pâté.
Changes of Volatile Compounds, Lactic Acid Bacteria, pH, and Headspace Gases in Kimchi, a Traditional Korean Fermented Vegetable Product
Authors: Kang J.H. , Lee J.H. , Min S. , Min D.B.
Published: July 2006

ABSTRACT Headspace volatiles of Kimchi stored at 5 °C increased over a 7 d period by 20.0% and then decreased from 7 to 27 d by 8.3%. Forty volatile compounds including 18 sulfur compounds were identified in Kimchi. Lactic acid bacteria in Kimchi increased from 3.1 to 4.5 (1 × 108cfu/mL) over a 17‐d period and decreased by 40% from 17 to 27 d. As the storage time increased from 2 to 27 d, pH decreased from 4.3 to 3.8, headspace oxygen decreased from 14.3 to 1.3%, and headspace carbon dioxide increased from 27.7 to 45.3%. Enzymatic reactions and chemical oxidations in Kimchi explained the changes of volatile compounds, lactic acid bacteria, pH, headspace oxygen and carbon dioxide.
Genetic Variation Within and Among Rainbow Trout, Onchorhynchus mykiss, Hatchery Populations from Iran Assessed by PCR‐RFLP Analysis of Mitochondrial DNA Segments
Authors: Sajedi R.H. , Aminzadeh S. , Naderi‐Manesh H. , Sadeghizadeh M. , Abdolhay H. , Naderi‐Manesh M.
Published: July 2006

ABSTRACT Samples were collected from 3 hatchery populations of 2 trout inbreeding centers (Kelardasht and Jajrood) and mitochondrial DNA (mtDNA) of these samples was studied by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). ND5/6 segment and a fragment that includes 12SrRNA, tRNA F, P, T, D‐loop, and a part of cyt.b of mtDNA were amplified and investigated using different restriction enzymes. Two patterns were observed using HaeIII, AvaII, RsaI, TaqI, and Hinf enzymes on gel electrophoresis, resulting in 9 haplotypes in ND5/6 segment, whereas only 1 pattern was observed for the fragment containing D‐loop. As a measure of intrapopulation diversity and interpopulation diversity, both heterozygocity and genetic distance were determined, respectively.
Mathematical Model for Prediction of Intermittent Drying and Pressing Process of Mullet Roe
Authors: Fan C.C. , Liaw S.P. , Fu W.R. , Pan B.S.
Published: July 2006

ABSTRACT A mechanical mullet roe drying process was designed to simulate the traditional intermittent sun drying‐pressing process. A transient 3‐dimensional diffusion equation was used to predict moisture content and moisture distribution using finite‐difference techniques. Drying curves decreased in a logarithmic manner without a constant drying period from 25 °C to 40 °C. At the pressing stage, the moisture distribution became even and the drying rate increased during the subsequent drying stage as compared to the continuous drying curve at comparable drying time. Total drying time was effectively saved by 30% for 3 cycles of 12 h‐12 h intermittent drying‐pressing followed by continuous drying until the mullet roe reached a water activity (Aw) of 0.85.
Modeling the Dielectric Properties of Ham as a Function of Temperature and Composition
Authors: Sipahioglu O. , Barringer S.A. , Taub I. , Prakash A.
Published: July 2006

ABSTRACT The dielectric properties of 19 different ham samples with different moisture (38.2% to 68.9%) and ash contents (1.78% to 6.80%) were measured at −35 to 70 °C at 2450MHz. Equations were developed as a function of temperature, moisture, and ash, and compared to literature equations. The dielectric constant decreased with ash content and increased with moisture content. It increased instead of decreasing with temperature. The dielectric loss factor increased with moisture content for moisture contents lower than 60.7%, then decreased for higher moisture contents. Ash content and temperature increased dielectric loss factor. Frozen samples had low dielectric activity that was increased by ash content above −20 to −10 °C.
Spatial Variation of Convective Heat Transfer Coefficient in Air Impingement Applications
Authors: Sarkar A. , Singh R.P.
Published: July 2006

ABSTRACT Spatial variation of heat transfer is an important factor in air impingement systems. Temperature data were obtained when a jet at room temperature impinged on a flat object initially at −50 °C to estimate heat transfer under freeze‐thaw conditions. Single and double circular jets and slot jets were examined. Temperature data were fit into empirical relationships for predicting heat transfer coefficients and their spatial variation for conditions common in impingement freeze‐thaw applications. For processing conditions involving cooling, the impingement surface was initially heated to a temperature of 70 °C and allowed to cool when subjected to impingement with room temperature air.
Evolution of Moisture Distribution During Storage in a Composite Food Modelling and Simulation
Authors: Guillard V. , Broyart B. , Bonazzi C. , Guilbert S. , Gontard N.
Published: July 2006

In order to predict moisture transfer in a composite food, a mathematical model was developed and tested on a 2‐components system constituted of a sponge‐cake in contact with a fresh wet filling. Using independent sorption kinetic experiment, a power law was found as representative of the effect of moisture content on water effective diffusivity of sponge‐cake. The parameters of power law was then adjusted using the model optimization procedure on moisture profiles measurements of sponge‐cake in contact with a 0.99 water activity agar gel at 20°C. The model was validated with 0.95 and 0.90 water activity agar gels and successfully used to predict moisture transfer in a real food (processed cheese/sponge‐cake system).
Evaluation of a Polymerase Chain Reaction–Based System for Detecting Salmonella Species from Pork Carcass Sponge Samples
Authors: Wu Chih‐Chuan , Liu Cheng‐I , Tsai Chin‐En , Yeh Kuang‐Sheng
Published: July 2006

Pork carcass sponge samples (n = 230) collected from 10 Taiwanese slaughter plants were screened for Salmonella using 2 methods: BAX® for Screening/Salmonella, a polymerase chain reaction‐based detection system and a culture method using SM‐ID agar as the selective plating medium. The BAX method identified 14 samples as positive for Salmonella. The 8 samples identified as Salmonella‐positive by the SM‐ID method were also BAX‐positive. Inoculation studies showed BAX detected Salmonella in samples having initial 1.4 × 101 cfu/mL Salmonella inoculum prior to the enrichment process in the presence of 3.0 × 106 cfu/mL of non‐Salmonella florae. BAX provides a rapid screening alternative to the culture method for Salmonella detection.
A Descriptive Model for the Kinetics of Gas Release in Different Types of Pizzas
Authors: Cabo M.L. , Pastoriza L. , Rodríguez J.J.
Published: July 2006

A model based on typical equations of microbial kinetics is proposed to describe gas release (GR) in ham, tuna, and meat pizzas packaged under different CO2‐enriched atmospheres: 20% CO2, 70% CO2, and 70% CO2 plus 500 mg/kg Nisaplin. CO2‐enriched atmospheres hardly influenced LAB growth but reduced GR, which points to the importance of yeasts for GR. Nonetheless, LAB also contributed significantly to GR, so Nisaplin also delayed GR. Gas release followed a diauxic pattern, the 2nd stage being presumably related to yeasts shifting from respiratory to fermentative metabolism once oxygen was depleted. However, storing pizzas for longer than 25 to 30 d does not seem appropriate in terms of shelf life, so the model proposed appears adequate for practical purposes.
Vapor‐phase Decontamination of Apples Inoculated with Escherichia coli
Authors: Sapers G.M. , Walker P.N. , Sites J.E. , Annous B.A. , Eblen D.R.
Published: July 2006

Improved methods of decontaminating apples containing human pathogens are required. In this study, application of gaseous antimicrobial agents was investigated. An apparatus, which transfers vapor from hot antimicrobial solutions to a treatment vessel, was evaluated with Golden Delicious apples inoculated with E. coli. Vapor from glacial acetic acid at 60°C provided population reductions exceeding 3.5 log10 CFU/g but induced discoloration. Vapor from heated hydrogen peroxide and chlorine dioxide solutions gave reductions ≤ 2 logs. However, chlorine dioxide gas, applied at 20°C in an airtight container, achieved a 4.5 log reduction, with minimal quality loss. Reductions achieved with this treatment greatly exceed those obtained by other decontamination methods for raw commodities.
The Effect of pH on Inactivation of Pathogenic Bacteria on Fresh‐cut Lettuce by Dipping Treatment with Electrolyzed Water
Authors: Yang H. , Swem B.L. , Li Y.
Published: July 2006

Fresh‐cut lettuce samples inoculated with S. Typhimurium, E. coli O157:H7 or L. monocytogenes were dipped into 300 ppm electrolyzed water (EW) at pH 4 to 9 and 30 °C for 5 min. The effects of treatment pH on bacterial reduction and visual quality of the lettuce were determined. The treatments at pH 4 and 8 resulted in the most effective inactivation of E. coli O157:H7, but the effect of pH was not significant (P > 0.05) for S. Typhimurium and L. monocytogenes. The treatment at pH 7 retained the best visual quality of lettuce, and achieved a reduction of approximately 2 log CFU/g for above 3 bacteria.
The Effect of Ethoxyquin and Vitamin E Supplementation on the Display Life of Beef Steaks
Authors: Maddock R.J. , Wulf D.M. , Mckenna D.R.
Published: July 2006

Steaks from cattle supplemented with 150 ppm ethoxyquin, an antioxidant, plus 150 or 250 IU of vitamin E per day, or 500 IU of vitamin E per day were evaluated for display life versus control steaks. Readings of a* indicated supplementation with vitamin E with or without ethoxyquin increased the display life of steaks compared with the controls. Thiobarbituric acid reactive substances (TBARS) were measured following 0, 3, and 7 d of retail display. All treatments had similar TBARS values on Day 0. On Days 3 and 7 control steaks had more lipid oxidation than the other treatments, with 500 IU of vitamin E having the least amount of oxidation. These data indicate supplementation with vitamin E improved the display life of steaks with no apparent interaction between vitamin E and ethoxyquin.
Effect of Oxygen Transmission Rate of the Packages, Light, and Storage Temperature on the Oxidative Stability of Extruded Oat Packaged in Nitrogen Atmosphere
Authors: Larsen H. , Magnus E.M. , Wicklund T.
Published: July 2006

The effect of oxygen transmission rate of the packages (including the use of an oxygen absorber), light, and temperature on the sensory stability of extruded oat pellets packaged in nitrogen atmosphere was studied over a period of 3 mo. A realistic approach for determining the maximum limit for the headspace O2‐concentration in packages for products susceptible to oxidation was proposed. By predicting the O2‐concentration in alternative packages by the Ambient Oxygen Ingress Rate method, the packages can easily be compared to select those not exceeding the experimentally determined maximum oxygen limit in the headspace during a certain time.
In Search of the “Ideal” Pear (pyrus spp.): Results of a Multidisciplinary Exploration
Authors: Jaeger S.R. , Lund C.M. , Lau K. , Harker F.R.
Published: July 2006

Preference mapping with 10 pears identified 3 segments among New Zealand consumers. While 1 segment preferred ripe European cultivars, another rejected only the seedling with strong off‐flavors. A 3rd segment combined the 2 former segments, but also rejected 2 hybrid samples. Survey responses to the question “To me, the ideal pear is ⃛” from a 2nd consumer sample confirmed the general preference for juicy and sweet pears, the key characteristics of ripeness. A separate appearance evaluation revealed 4 segments based on color and shape. Combining information from several sources resulted in suggestions for new breeding directions for pears, while highlighting the importance of appearance and the need for more extensive measurements.
Yield and Textural Properties of Tofu as Affected by the Changes of Phytate Content During Soybean Storage
Authors: Hou H. J. , Chang K. C.
Published: July 2006

ABSTRACT: Soybeans stored under 4 conditions were analyzed for the degradation of phytate and its effects on tofu qualities. Phytate in soybeans was hydrolyzed significantly under the adverse conditions for 9 mo, but decreased slightly under 3 mild conditions for 18 mo. Phytate degradation contributed to an increase in titratable acidity. When the phytate contents of soymilk were selectively reduced by 11.3% and 17.5% by phytase, while other components remained unchanged, tofu yield increased significantly but texture became softer. Tofu yield decreased and hardness increased in beans stored in the adverse conditions. Phytate degradation during adverse storage played a minor, indirect role in the deterioration of soybeans for tofu making.
Aroma‐active Components of Liquid Cheddar Whey
Authors: Karagül‐Yüceer Y. , Drake M.A. , Cadwallader K.R.
Published: July 2006

ABSTRACT:Fresh Cheddar cheese whey batches from 2 processing plants and 4 starter culture rotations were extracted with diethyl ether followed by isolation of volatiles by high‐vacuum distillation. Odorants were evaluated by gas chromatography‐olfactometry (GCO) and aroma extract dilution analysis (AEDA). 2,3‐butanedione (buttery), hexanal (green), 2‐acetyl‐1‐pyrroline (popcorn), methional (potato), (E,E)‐2,4‐decadienal (frying oil) and (E,E)‐2,4‐nonadienal (frying oil) were potent neutral/basic aroma‐active compounds identified in all whey samples. Odor intensities of hexanal, (E,E)‐2,4‐nonadienal, 2,3‐butanedione, and (E,E)‐2,4‐decadienal were variable. Short‐chain volatile acids were predominant in acidic fractions and their intensities differed among the whey samples. GCO findings agreed with quantitation results. Liquid whey aroma components are influenced by starter culture rotation.
Textural Properties of Pork Frankfurters Containing Thermally/Enzymatically Modified Soy Proteins
Authors: Feng J. , Xiong Y.L. , Mikel W.B.
Published: July 2006

ABSTRACT: Native, heated, and enzyme (Alcalase®, Flavourzyme™)‐hydrolyzed soy protein isolates (SPI, 2%) were incorporated into pork frankfurters. Both heated and hydrolyzed SPIs improved product‐cooking yield. The addition of heated and Alcalase‐hydrolyzed SPIs produced a fine‐stranded microstructure and improved frankfurter hardness, while addition of Flavourzyme‐hydrolyzed SPI resulted in a more porous gel structure with reduced hardness, cohesiveness, and breaking strength. These results indicate that functional performance of SPI in frankfurters is critically affected by its pre‐application treatment.
Lipid Oxidation and Carotenoids Content in Frying Oil and Fried Dough Containing Carrot Powder
Authors: Lee J. , Kim M. , Park K. , Choe E.
Published: July 2006

ABSTRACT: Lipid oxidation and carotenoids in frying oil and carrot‐added dough during frying were studied. Flour dough containing carrot powder was sheeted at 0.1 cm thickness and was then cut to squares to be fried. Each frying was performed in 160°C soybean oil for 1 min and repeated every 20 min for 20 h. Carrot in the dough decreased significantly the oxidative stability of frying oil and fried dough (p < 0.05). Carotenoid content in frying oil increased as frying was repeated due to dissolution of carotenoids from the dough containing carrot; however, there was no significant difference in carotenoid content among the dough fried in the oil with different number of fryings.
Measurement by ELISA of Active Lectin in Dietary Supplements Containing Kidney Bean Protein
Authors: Boniglia C. , Fedele E. , Sanzini E.
Published: July 2006

ABSTRACT: We describe an ELISA assay to measure the active lectin content in dietary supplements containing protein extracts from Phaseolus vulgaris. Phytohemagglutinin (PHA) is known to induce serious consequences for metabolism and health when consumed raw or only lightly cooked. The ELISA was performed using plates preliminarily coated with porcine thyroglobulin, which has high specificity binding to active lectin. The bound active lectin was detected by a rabbit anti‐PHA IgG and a secondary antibody enzyme conjugate. An assessment of linearity and analytical range were also performed. The data obtained showed good repeatability, specificity and a limit of quantification of 15 ng of PHA. The sensitivity of the method corresponds to 30 ppm.
Modeling the Spaghetti Hydration Kinetics During Cooking and Overcooking
Authors: Del Nobile M.A. , Buonocore G.G. , Panizza A. , Gambacorta G.
Published: July 2006

ABSTRACT: A mathematical model to predict the hydration kinetics of spaghetti during cooking and overcooking is presented. The phenomena involved during the hydration process, such as starch crystalline domains melting kinetics, water diffusion, macromolecular matrix relaxation kinetics, and “residual deformation” release kinetics, were separately described. To validate the developed model, water sorption tests on commercially available spaghetti strands were run at 100 °C. In particular, the weight, diameter, and length of spaghetti strands were monitored over a period of 200 min. The fitting and predictive ability of the model was successfully tested, corroborating the validity of the approach used to derive the model.
Mass Transfer in Strawberry Tissue During Osmotic Treatment I: Microstructural Changes
Authors: Ferrando M. , Spiess W.E.L.
Published: July 2006

ABSTRACT: Microstructural changes in strawberry tissue were quantified during osmotic treatment (OT) with sucrose solutions in concentrations of 15 to 65 (% w/w). The response‐surface method was used to determine how the process variables (processing time and concentration) influence cellular shrinkage and cell destruction. With regard to the concentration of the osmotic solution, the kinetics of cell destruction followed a 1st‐order model. The diffusional approach for modelling water transport in a layer of cells inside the strawberry tissue showed that water diffusivity is related to the concentration of the sucrose solution. Water diffusivity ranged from 16 ± 2 10−12 to 6.2 ± 0.6 1012.2 m2/s with sucrose solutions in concentrations between 15 and 65 (% w/w).
Large Deformation Properties of Gels and Model Comminuted Meat Products Containing Lupin Protein
Authors: Mavrakis C. , Doxastakis G. , Kiosseoglou V.
Published: July 2006

ABSTRACT: The fracture properties of Lupin seed protein isolate (LSPI) gels prepared by heat‐treatment of protein dispersions have been studied at large deformations, by a uniaxial compression test. Fracture parameter values depended both on the method used for isolate preparation and the presence of sodium chloride. The results are explained in terms of LSPI composition and protein solubility. Incorporation of lupin isolate to a model comminuted meat‐product system, resulted in a significant increase in fracture stress value while textural parameter values of the heated system such as hardness, fracturability, gumminess, and chewiness were also affected.
Microwave Dielectric Properties of Solid and Liquid Foods Investigated by Time‐domain Reflectometry
Authors: Miura N. , Yagihara S. , Mashimo S.
Published: July 2006

ABSTRACT: Microwave dielectric relaxation measurements by a time‐domain reflectometry (TDR) method were performed on solid and liquid foods, covering the frequency range between 100 kHz and 10 GHz. Carrots, radishes, potatoes, rice, milk, cheese, egg whites, egg yolks, fish, chicken, agar aqueous gel, gelatin aqueous gel, and ovalbu‐min aqueous gel were examined. The relaxation processes caused by the reorientation of free water and bound water, interfacial polarization, and polymer chain motion were discussed. Whiskey, beer, and wine also were examined by TDR, and a relaxation process caused by reorientation of molecular dipoles in water and alcohol was observed. The obtained dielectric parameters for beverages were compared with those of ethanol‐water mixtures.
Effects of Starter Culture and Coagulating Enzymes on Viscoelastic Behavior and Melt of Mozzarella Cheese
Authors: Dave R.I. , Sharma P. , Muthukumarappan K.
Published: July 2006

ABSTRACT: Mozzarella cheeses were made with a single culture (SC) or a mixed culture (MC) using 1x or 6x of cheese coagulants chymosin or Cryphonectria parasitica (CP). Melt area increased only by approximately 80% in cheeses made with SC against 230% in the cheeses made with MC after 30 d of storage. Soluble nitrogen was also higher in MC cheeses as compared to SC cheeses. Both the elastic (G’) and the viscous (G”) modulus decreased with storage. Decrease in both moduli was greater in the MC cheeses at 6× enzyme level compared to SC cheeses at 1× enzyme level. The synergism between coagulating enzyme and starter culture was beneficial, which improved melt and flow of Mozzarella cheese and had profound effects on the viscoelastic properties of Mozzarella cheese.
Reduction of Escherichia Coli O157:H7 and Lactobacillus Plantarum Numbers on Fresh Beef by Polylactic Acid and Vacuum Packaging
Authors: Lim K. , Mustapha A.
Published: July 2006

ABSTRACT: The efficacy of 2% molecular weight 240, 2% molecular weight 360 polylactic acid (PLA), and an equal mix of both at reducing numbers of Escherichia coli O157:H7 and Lactobacillus plantarum on raw beef was determined. Fresh beef cubes inoculated with either organism were dipped in PLA solutions or wrapped in PLA‐sprayed films. Samples were vacuum packaged and stored at 4°C for 42 d. Treated samples maintained a significantly lower pH than controls. Growth of E. coli O157:H7 was totally inhibited by both PLA treatments by up to 7.29 log10 CFU/cm2 when the spray method was used. However, PLA treatments against L. plantarum were not very effective.
A PCR Assay for Specific Detection of the Pandemic Vibrio parahaemolyticus O3:K6 Clone from Shellfish
Authors: Marie Yeung P.S. , DePaola A. , Kaysner C.A. , Boor K.J.
Published: July 2006

Abstract

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The current standard method for identifying Vibrio parahaemolyticus serotype O3:K6, an emerging pathogen with apparent enhanced virulence characteristics, typically takes 4 to 6 d to complete and requires serotyping. To provide a more rapid strategy, we optimized a polymerase chain reaction (PCR)‐based assay for specific detection of V. parahaemolyticus O3:K6. Of 78 V. parahaemolyticus isolates and other related species; only strains classified into the V. parahaemolyticus O3:K6 clonal group (n= 39) showed positive results in the PCR assay. The assay detected 2.3 cells/PCR reaction and 310 cells/g using bacterial cultures and inoculated oyster samples, respectively. Sensitive and specific detection of V. parahaemolyticus O3:K6 was possible following a 6‐h enrichment.
Mixed Model Analysis of Sensory Characteristics of Irradiated Apple Cider
Authors: Wang H. , Reitmeier C.A. , Glatz B.A. , Carriquiry A.L.
Published: July 2006

Trained panelists evaluated the sensory characteristics of 4 kinds of apple ciders: untreated, pasteurized, and irradiated at 2 or 4 kGy. A mixed model analysis was implemented. From among several realistic models, a mixed model without an interaction term was selected for fitting most of the sensory attributes studied. Irradiated ciders were lighter in color and had less apple flavor than untreated cider. Cider irradiated at both 2‐ and 4‐kGy doses contained more “cardboard‐like” flavor compared to untreated and pasteurized ciders. Consequently, “cardboard‐like” was a suitable term for the description of the specific off‐flavor in irradiated cider with preservative.
Physical, Chemical, and Sensory Properties of Bologna Sausage Made with Ostrich Meat
Authors: Fernández‐López J. , Sayas‐Barberá E. , Navarro C. , Sendra E. , Pérez‐Alvarez J.A.
Published: July 2006

Three formulations of bologna were prepared, differing only by the lean meat used: (1) ostrich meat from Iliofibularis muscle (fan thigh), (2) ostrich meat from Femorotibialis medius muscle (tip thigh), and (3) beef meat from Subscapularis muscle (shoulder). Physical, chemical, and sensory analyses were made. The final products formulated with ostrich meat, although having a dark appearance, were acceptable in chemical composition and other sensory characteristics. The low fat and high protein content for ostrich bolognas will help to ensure that, if marketed in sufficient quantities, ostrich meat can successfully compete with other healthy meat products. The ostrich meat (Iliofibularis muscle) formula reached the highest general quality scores in the sensory evaluation.
The Importance of Taste and Other Product Factors to Consumer Interest in Nutraceutical Products: Civilian and Military Comparisons
Authors: Cardello A.V. , Schutz H.G.
Published: July 2006

A conjoint analytic study was conducted with military and civilian consumers to assess the importance of taste and other product characteristics to the intended use of nutraceutical products. Taste was found to be the most important factor for both consumer groups, followed by the benefit to be achieved, the source of the benefit claim, required dosage, mode of consumption, and product type (natural compared with synthetic). Interest among the military was greatest for products that increased muscle mass, whereas interest among civilians was greatest for products that improved thinking. For both groups, required frequency of consumption greater than 3 times a day had a negative influence on probable use, whereas consumption in a capsule form was viewed most desirable.
Assessment of the Antioxidant Properties During Storage of a Dessert Made from Grape, Cherry, and Berries
Authors: García‐Alonso F.J. , Periago M.J. , Vidal‐Guevara M.L. , Cantos E. , Ros G. , Ferreres R , Abellán P.
Published: July 2006

A 1‐y storage trial was designed involving different temperatures (8, 21, and 30 °C) to assess the antioxidant properties of a dessert formulated with concentrated juices of grape, blackberry, blackcurrant, raspberry, and cherry. The total antioxidant activity (TAA) of the dessert was measured as the scavenging capacity of the 2,2′‐azino‐di‐[3‐ethylbenzothiazoline‐6‐sulphonate] radical cation (ABTS) and as its iron‐reducing ability (FRAP). Color was spectrophotometrically measured, and vitamin C and phenolics were analyzed by HPLC. The color parameters and the concentrations of different antioxidant compounds were affected by storage conditions, especially in samples stored at 30 °C, although the TAA remained practically invariable during storage.
Texture and Flavor Characteristics of Beverages Containing Commercial Thickening Agents for Dysphagia Diets
Authors: Lotong V. , Chun S.S. , IV Chambers E. , Garcia J.M.
Published: July 2006

Starch‐based thickeners often are recommended to facilitate fluid intake for dysphagia patients. Four beverages (water, milk, orange juice, apple juice) were prepared to a “honey‐like” consistency using 4 commercially available starch‐based thickeners. Sensory characteristics of the beverages were described using descriptive sensory analysis. The brands of thickeners differed in the perceived viscosity of the products they produced. With thickeners, the main flavors of the base beverages were suppressed, all imparted a starchy flavor, and some products imparted slight off‐flavors, such as metallic, astringent, or bitter, and a grainy texture that might be perceived as reducing quality. This sensory information could be related to physicochemical information to improve product quality.
Thermal Effects on Fast Skeletal Myosins from Alaska Pollock, White Croaker, and Rabbit in Relation to Gel Formation
Authors: Fukushima H. , Satoh Y. , Nakaya M. , Ishizaki S. , Watabe S.
Published: July 2006

Thermodynamic properties in differential scanning calorimetry (DSC) and changes in viscoelasticity upon heating of myosins from white croaker, Alaska pollock, and rabbit fast muscles were investigated in relation to their thermal gel formation abilities. Alaska pollock myosin unfolded in a wide temperature range of 19 to 69°C as revealed by DSC, whereas rabbit myosin unfolded in very narrow range of 32 to 56°C. Thermal unfolding of white croaker myosin occurred in an intermediate temperature range of 30 to 60°C. Viscoelastic properties determined as storage modulus, G′, and loss modulus, G″, reflected differences observed in DSC for the 3 myosins.
Effects of Commercial‐scale Pulsed Electric Field Processing on Flavor and Color of Tomato Juice
Authors: Min S. , Zhang Q.H.
Published: July 2006

Effects of commercial‐scale pulsed electric field (PEF) processing on the flavor and color of tomato juice during storage at 4 deg;for 112 d were studied. Tomato juice was prepared by hot break at 88°C for 2 min and then thermally processed at 92° for 90 s or PEF processed at 40 kV/cm for 57 μs. The PEF‐processed tomato juice retained more flavor compounds of trans‐2‐hexenal, 2‐isobutylthiazole, cis‐3‐hexanol than thermally processed or unprocessed control tomato juice (P < 0.05). PEF‐processed juice had significantly lower nonenzymatic browning and higher redness than thermally processed or control juice (P < 0.05). Sensory evaluations indicated that the flavor of PEF‐processed juice was preferred to that of thermally processed juice (P < 0.01).