bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in aboveground primary production and carbon and nitrogen pools accompanying woody plant encroachment in a temperate savanna
Authors: HUGHES R. FLINT , ARCHER STEVEN R. , ASNER GREGORY P. , WESSMAN CAROL A. , McMURTRY CHAD , NELSON JIM , ANSLEY R. JAMES
Published: July 2006

When woody plant abundance increases in grasslands and savannas, a phenomenon widely observed worldwide, there is considerable uncertainty as to whether aboveground net primary productivity (ANPP) and ecosystem carbon (C) and nitrogen (N) pools increase, decrease, or remain the same. We estimated ANPP and C and N pools in aboveground vegetation and surface soils on shallow clay and clay loam soils undergoing encroachment by Prosopis glandulosa in the Southern Great Plains of the United States. Aboveground Prosopis C and N mass increased linearly, and ANPP increased logarithmically, with stand age on clay loam soils; on shallow clays, Prosopis C and N mass and ANPP all increased linearly with stand age. We found no evidence of an asymptote in trajectories of C and N accumulation or ANPP on either soil type even following 68 years of stand development. Production and accumulation rates were lower on shallow clay sites relative to clay loam sites, suggesting strong edaphic control of C and N accumulation associated with woody plant encroachment. Response of herbaceous C mass to Prosopis stand development also differed between soil types. Herbaceous C declined with increasing aboveground Prosopis C on clay loams, but increased with increasing Prosopis C on shallow clays. Total ANPP (Prosopis+herbaceous) of sites with the highest Prosopis basal area were 1.2 × and 4.0 × greater than those with the lowest Prosopis basal area on clay loam and shallow clay soils, respectively. Prosopis ANPP more than offset declines in herbaceous ANPP on clay loams and added to increased herbaceous ANPP on shallow clays. Although aboveground C and N pools increased substantially with Prosopis stand development, we found no corresponding change in surface soil C and N pools (0–10 cm). Overall, our findings indicate that Prosopis stand development significantly increases ecosystem C and N storage/cycling, and the magnitude of these impacts varied with stand age, soil type and functional plant traits
Variation and infectivity neutralization in influenza
Authors: Knossow Marcel , Skehel John J.
Published: July 2006

Worldwide epidemics of influenza are caused by viruses that normally infect other species, particularly waterfowl, and that contain haemagglutinin membrane glycoproteins (HAs) to which the human population has no immunity. Anti‐HA immunoglobulins neutralize influenza virus infectivity. In this review we outline structural differences that distinguish the HAs of the 16 antigenic subtypes (H1–16) found in viruses from avian species. We also describe structural changes in HA required for the effective transfer to humans of viruses containing three of them, H1, H2 and H3, in the 1918 (Spanish), the 1957 (Asian) and the 1968 (Hong Kong) pandemics, respectively. In addition, we consider changes that may be required before the current avian H5 viruses could pass from human to human.
The potential association between smoking and endodontic disease
Authors: Duncan H. F. , Pitt Ford T. R.
Published: July 2006

The aim of this review was to analyse the literature to assess the possibility of an association between smoking and endodontic disease and the prognosis of endodontically treated teeth. The review of the prognosis of endodontically treated teeth involved taking account of any potential associations with smoking and endodontic disease and marginal periodontitis, and smoking and prosthodontic outcomes. In addition, the role of smoking in implant failure and surgical wound healing was analysed with a view to drawing parallels regarding the possible implications of smoking on the outcome of surgical endodontics. A MEDLINE and Cochrane library search including smoking and various endodontic keyword searches identified three papers which discussed the variables, and did not just mention them separately in the text. The literature demonstrates a paucity of evidence relating smoking with endodontic disease and prognosis, but nevertheless presents evidence of a possible influence on the prognosis of endodontically treated teeth in smokers and a likely increase in surgical complications. The possible merits of a smoking cessation protocol prior to surgical endodontics are also discussed.
Effect of heat sterilization on surface characteristics and microstructure of Mani NRT rotary nickel–titanium instruments
Authors: Alexandrou G. , Chrissafis K. , Vasiliadis L. , Pavlidou E. , Polychroniadis E. K.
Published: July 2006

Aim  To evaluate the effect of repeated dry heat sterilization on surface characteristics and microstructure of Mani nickel–titanium rotary instruments.

Methodology  Thirty‐three new Mani NRT instruments, size 30, taper 0.04 and 25 mm in length were examined. Twenty‐seven instruments were divided into three groups for surface characterization by scanning electron microscopy (SEM). In the first group (n = 3), instruments were examined in the ‘as‐received’ condition and after they had been subjected to 11 sterilization cycles. In the second and third subgroups (n = 12), 12 instruments were prepared for cross‐section and a further 12 for longitudinal sectional analysis and evaluated in subgroups of three, after 0, 1, 6 and 11 sterilization cycles. The remaining six instruments were analysed with differential scanning calorimetry (DSC), three in the ‘as‐received’ condition and three after being subjected to 11 cycles of sterilization.

Results  Scanning electron microscopy observations indicated the presence of debris, pitting and deep milling marks in both new and sterilized files. After 11 sterilization cycles, debris remained and surface roughness was increased significantly (P = 0.05). DSC analyses showed that the specimens in the ‘as‐received’ condition and after 11 sterilization cycles were in the austenite phase or a mixture of austenite and R‐phase at 37 °C.

Conclusions  The machining defects and structural imperfections of new Mani instruments are indicative of the difficulty in manufacturing nickel–titanium endodontic instruments. DSC measurements suggest that Mani instruments are capable of superelastic behaviour under clinical conditions.
Efficacy of automated versus hand instrumentation during root canal retreatment: an ex vivo study
Authors: De Carvalho Maciel A. C. , Zaccaro Scelza M. F.
Published: July 2006

Aim  To compare automated and manual instrumentation techniques for removing filling material from root canal walls during root canal retreatment.

Methodology  One hundred extracted human single‐rooted teeth were root filled and stored. Specimens were divided into two groups: group A, Endofill plus gutta‐percha; group B, Sealer 26 plus gutta‐percha. The filling material was removed using the following techniques: group I – Gates–Glidden and K‐type files; group II – ProFile; group III – ProTaper; group IV – K3; group V– Micro Mega Hero 642. The remaining filling debris on the root canal walls were assessed radiographically, images were digitized and analysed using Image ProPlus software. The roots were split for evaluation in a stereomicroscope by epiluminescence and photomicrographs were taken for further analysis. The area covered with filling debris was analysed by means of Student's t‐test to compare the evaluation methods. The student's t‐test was also used to compare the removal of filling materials. An anova test was applied to compare the different techniques (P < 0.05).

Results  A significant difference occurred between radiographic and photomicrographic evaluation methods (P < 0.05). No significant difference was observed between the filling materials on terms of their removal (P > 0.05). Manual instrumentation left more filling debris on the root canal walls when compared to K3 (P < 0.05) and ProTaper (P < 0.01).

Conclusions  A photomicrographic method by epiluminescence was more effective than the radiographic method to evaluate filling debris. There was no significant difference between the filling materials in terms of their removal. K3 and ProTaper were more efficient than manual instrumentation.
Reassessment of Some Fruit and Vegetable Pectin Levels
Authors: BAKER ROBERT A.
Published: July 2006

Several reviews of pectin as a soluble fiber have included unreliable tables of pectin content for fruits and vegetables. Values given for ranges of pectin content in the fresh, edible portion are actually presented in original reports variously as peel pectin content, dry weight values, soluble rather than total pectins, and some values have been for unripe fruit. This has resulted in reporting pectin levels for some products that may be 2‐10 times higher than other published data on the same product. This report examines the original sources and errors of such data and, when available, provides other more substantiated published values.
Citrus Tissue Extracts Affect Juice Cloud Stability
Authors: CAMERON RANDALL G. , BAKER ROBERT A. , GROHMANN KAREL
Published: July 2006

Salt extractable proteins were isolated from hand expressed juice, rag and peel of Valencia oranges. Each tissue extract was divided into dialysis supernatant (DS) and precipitate (DP) (forms during dialysis). DP, DS and DS heated for 2 min at 80°C (HDS) were added to pasteurized, reconstituted frozen concentrated orange juice at 5 U · mL−1 of pectinmethylesterase. Samples were incubated either at 25°C for 14 days or 4°C for 28 days and periodically sampled to determine the effects of tissue extracts on juice cloud stability. Tissue specific differences were observed for the rate of juice cloud precipitation and among the HDS, DS, and DP fractions of a given tissue. HDS fractions destabilized juice cloud more rapidly than DS or DP at both 25 and 4°C.
Inorganic Cations and Polyamines Moderate Pectinesterase Activity
Authors: LEITING V.A. , WICKER L.
Published: July 2006

Inorganic and organic cations influenced pectinesterase (PE) activity and solubilization from Marsh grapefruit pulp. Activity increased to 281%, 183%, and 130% with lead acetate (6.8 mM), ferric chloride (0.2 mM), and calcium chloride (20 mM), respectively. The polyamines, putrescine, spermidine, and spermine had negligible stimulating effect. All cations tested inhibited PE activity at higher concentrations. Solubilization of total PE was decreased and thermostable PE (TS‐PE) was not affected by polyamines. There was a progressive decline in total PE activity above 1.6 mM spermidine, 7.6 mM putrescine and 20.0 mM spermine. Loss of activity upon solubilization suggests that the TL‐PE‐pectate complex stabilized TL‐PE. No change in TS‐PE activity suggests that it may be bound with greater affinity, physically entrapped, or non‐electrostatically bound.
Biopolymers Produced by Cross‐linking Soybean 11S Globulin with Whey Proteins using Transglutaminase
Authors: YILDIRIM M. , HETTIARACHCHY N.S.
Published: July 2006

Heterogeneity of biopolymers was determined by cross‐linking acetylated‐11S acidic subunits (Ac‐11S) of soy protein with α‐lactalbumin and β‐lactoglobulin. The extent of polymerization was determined by electrophoresis and HPLC. Differential scanning calorimetry (DSC) was used to determine thermal properties of starting proteins and biopolymers. HPLC data demonstrated the absence of biopolymers from Ac‐11S, acetylated α‐lactalbumin and acetylated β‐lactoglobulin when each was incubated separately with transglutaminase (TG). However, Ac‐11S formed biopolymers with α‐lactalbumin and β‐lactoglobulin when TG was added. TG catalyzed the formation of heterologous and homologous biopolymers from whey protein isolate (WPI) and soybean 11S globulin (11S). Cross‐linking WPI and 11S provided biopolymers with improved heat stability which may be useful to provide functionality to food products.
Water Uptake, Protein Solubility, and Protein Changes of Cod Mince Stored on Ice as Affected by Polyphosphates
Authors: CHANG C.C. , REGENSTEIN J.M.
Published: July 2006

Water uptake ability (WUA) and protein solubility of cod mince were higher with sodium hexametaphosphate (SHMP) than with sodium tripolyphosphate (STP) or untreated controls during ice storage. WUA increased significantly with SHMP concentration up to 0.7% SHMP but above that WUA decreased, although protein solubility continued to increase. The SDS‐PAGE results showed that extraction of a specific amount of water‐soluble protein, perhaps including some myosin heavy chain (MHC, 200 kd), correlated with high WUA. However, excess extraction of MHC may cause destruction of the structural matrix of the insoluble protein network, preventing it from holding water.
Lactate Dehydrogenase Activity as an Endpoint Heating Indicator in Cooked Beef
Authors: STALDER J.W. , SMITH G.L. , KEETON J.T. , SMITH S.B.
Published: July 2006

Lactate dehydrogenase (LDH, E.C. 1.1.1.27) activity, specifically LDH5 isoenzyme, declined significantly when bovine Semimembranosus (SM) slurries were heated from 57° to 66°C. When SM whole muscle roasts were brine pumped and oven‐cooked, total LDH and specific activities declined proportionately from 57° to 63°C resulting in almost no activity at 63°± 0.5°C. LDH activities were consistently higher in younger cattle and lower in older cattle for SM, Infraspinatus (IN) and Longissimus dorsi (LD) muscles and were lowest overall in the IN. LDH colorimetric and fluorescent assays were more accurate indicators for predicting beef roast heating temperature endpoints between 60° and 63°C than the USDA‐FSIS method.
Pectic Substance Degradation and Texture of Carrots as Affected by Pressurization
Authors: KATO NORIKO (HYAKUMOTO) , TERAMOTO AI , FUCHIGAMI MICHIKO
Published: July 2006

Heated pectin was degraded by transelimination (β‐elimination) above pH 5 and by hydrolysis below pH 2, but pressurized pectin did not degrade. Thus cooked carrots decreased in firmness, but pressurized carrots did not. Pressurizing above 200 MPa slightly increased rupture strain. Galacturonic acid levels decreased in carrots cooked for 30 min. Total pectin in pressurized carrots was the same as in cooked for 3 min. However, with increased pressure, the amount of high methoxyl pectin in carrots decreased while low methoxyl pectin increased. Thus, the effects of pressurization on pectin degradation (transelimination) and texture of carrots were different from those of heating.
Protein and Salt Effects on Ca2+‐Induced Cold Gelation of Whey Protein Isolate
Authors: HONGSPRABHAS P. , BARBUT S.
Published: July 2006

Increasing whey protein concentration (from 6 to 10% w/v) decreased gel opacity but increased gel strength and water‐holding capacity (WHC). Increasing CaCl2, concentration (from 5 to 150 mM) increased gel opacity and gel strength at the high protein concentration (i.e., 10%). However, it lowered gel strength at protein concentration > 10%. Young's modulus and distance to fracture values indicated that gels were most rigid at 30 mM CaCl2, at which point the extent of aggregation (measured by turbidity) was the highest. Increasing CaCl2 concentration from 5 to 150 mM slightly affected the WHC of Ca2+‐induced gels. Protein concentration was the major factor in determining fracture properties and WHC.
Fat and Water Composition Affects Residual Catalatic Activity in Chicken Breast Heated to Specific End‐point Temperatures
Authors: LIU F. , ANG C.Y.W. , HUANG Y‐W. , TOLEDO R.T.
Published: July 2006

Fat and water contents of meat tissues strongly influence their thermo‐physical properties. Seven groups of ground chicken breast meat containing varying amounts of fat and water were prepared for this investigation. Each group was heated to end‐point temperatures (EPTs) of 69.0 to 71.0°C at 0.5°C intervals. Severity of heat treatments was evaluated by the total process lethality calculated using the General Method. The fat and water contents affected the heating time to reach specific EPTs and the residual catalatic activity at EPTs of 69.0, 69.5 and 70.0°C, but did not affect total process lethality. The variation of the catalase method for determining EPT was related to the sample composition.
Ripening Characteristics of Light Irradiated Tomatoes
Authors: LEE GWI‐HYUN , BUNN J.M. , HAN Y.J. , CHRISTENBURY G.D.
Published: July 2006

Red color development in breaker stage tomatoes was accelerated by 3 min red (R) irradiation and delayed by 3 min far‐red (FR) irradiation during the first 4 days of ripening. The effects were reversible and color development effective whether the interval between R and FR treatments was 1 day or 2 days. Firmness values of tomatoes irradiated with R were lower than those irradiated with FR, treated with ethylene, or stored in darkness. Light irradiation had the greatest effect on color development in tomatoes irradiated at the breaker and turning stages of maturity compared to those irradiated at the pink and light red stages.
Processing to Improve Quality of Dehydrated Precooked Pinto Beans
Authors: CAI T.D. , CHANG K.C.
Published: July 2006

The firmness of precooked and rehydrated beans after soaking in water at 30°C/2 hr and 82°C/1 hr was lower than that after soaking at 82°C/1 hr or 22°C/12 hr. The 22°C/12 hr soaking yielded the lowest butterflying (8.0%). Steam precooking at 100°C/1 hr produced less splitting, lighter color, and firmer texture than pressure precooking. High initial humidity dehydration reduced splitting. Beans after soaking at 30°C/2 hr and 82°C/1 hr, precooking at 100°C/1 hr, and dehydrating at 65°C/6 hr with initial 95% relative humidity were better regarding firmness, butterflying (11.6%), and moisture content (10.4%).
Biochemical and Physicochemical Properties of Actomyosin from Frozen Pre‐ and Post‐spawned Hake
Authors: MONTECCHIA C.L. , ROURA S.I. , ROLDÁN H. , PÉREZ‐BORLA O. , CRUPKIN M.
Published: July 2006

Protein solubility, reduced and intrinsic viscosity, and enzymatic activities of actomyosin showed that frozen fillets from pre‐spawned hake, stored at — 20°C, deteriorated faster than those from post‐spawned hake. The post‐spawned actomyosin showed an 18% increase in reduced viscosity, a larger hydrophilic surface, and an increase (P<0.001) in Mg2+‐, Mg2+‐EGTA‐ and Ca2+‐ATPase activities. Protein solubilities of 85.5 52.5 ± and 33 ± 2.0% were obtained at the end of storage for post and pre‐spawned fillets, respectively. Enzymatic activities of post‐spawned fillets persisted up to 60 days. No changes were detected in characteristic polypeptide bands of actomyosin or in the myosin/actin ratio related to either gonadal condition during storage.
Thermal and Calcium Pretreatment Affects Texture, Pectinesterase and Pectic Substances of Frozen Sweet Cherries
Authors: ALONSO JESÚS , CANET WENCESLAO , RODRIGUEZ TERESA
Published: July 2006

Freezing causes loss of turgidity and firmness in sweet cherries. Thermal pretreatment at 50°C for 10 min followed by immersion in 100 mM CaCl2 and thermal pretreatment at 70°C/2 min with or without immersion in 100 mM CaCl2 prevented freezing‐induced loss of firmness. Thermal pretreatments increased the pectin fraction soluble in EDTA, reduced the degree of pectin esterification, and increased both the concentration of divalent cations in the cell wall and the pectinesterase activity bounded to the cell wall. Immersion in CaCl2 increased the concentration of Ca2+ cations in the cell wall and enhanced the effect of thermal pretreatments on pectinesterase activity.
Corn Alkaline Cooking Properties Related to Grain Characteristics and Viscosity (RVA)
Authors: ALMEIDA‐DOMINGUEZ H.D. , SUHENDRO E.L. , ROONEY L.W.
Published: July 2006

The relationship between kernel properties and alkaline cooking characteristics of 14 corn cultivars with different kernel characteristics was evaluated. Corn hardness was measured by abrasion (TADD), flotation, subjective ratings and a viscometric technique (RVA). Hard corn required longer time for cooking as both cooking and steeping hydration rates were lower compared to soft corn. RVA viscosity measurements were correlated with hardness from TADD, flotation and subjective tests, and alkaline cooking parameters. The rate of water uptake during simmering was correlated with RVA viscosity slope. Hard corn endosperm particles consistently required longer time for hydration and gelatinization of starch to develop viscosity. RVA data complemented flotation hardness data to predict cooking properties. RVA could be used as a model to predict cooking properties of corn.
Formulation and Processing of a Heat Stable Calcium‐fortified Soy Milk
Authors: YAZICI F. , ALVAREZ V.B. , MANGINO M.E. , HANSEN P.M.T.
Published: July 2006

Calcium‐fortified soy milk (200 mg/100g) was formulated by adding water (85–90°C) full‐fat soy flour (10%), sucrose (2.75%) and soy protein isolate (2.25%). Following homogenization, the blend was twice clarified and pasteurized at 65°C/30 min before refrigeration. Samples of the soy milk (45°C) were adjusted to pH 8 before adding calcium lactogluconate (1.55%) and varying amounts of sodium hexametaphosphate or potassium citrate. Samples with 1.25% potassium citrate the best heat stability. For successful calcium fortification, it is recommended to maintain a calcium‐to‐protein ratio < 38 mg/g and to use an appropriate sequestering agent at a molar ratio of 0.8/mole calcium.
Carrageenan Effects on Salt‐Soluble Meat Proteins in Model Systems
Authors: DeFREITAS Z. , SEBRANEK J.G. , OLSON D.G. , CARR J.M.
Published: July 2006

The effects of κ‐, ι‐, and λ‐carrageenans (CGNs) on the rheological properties, water loss, and ultrastructure of salt‐soluble meat protein (SSMP) gels were evaluated. κ‐CGN increased gel strength and water retention of SSMP, suggesting that a molecular interaction may have occurred. However, no indications of specific molecular interactions were observed upon addition of stabilizing/destabilizing reagents. Electron microscopy indicated that improvement of water retention and texture of SSMP/κ‐CGN gels may be due to physical rearrangement of the κ‐CGN and SSMP molecules.
Viscoelasticity of Frozen/Thawed Egg Yolk
Authors: TELIS V.R.N. , KIECKBUSCH T.G.
Published: July 2006

Dynamic rheological measurements indicate that the gel formed during freezing is based on physical aggregation rather than chemical binding, with a nonhomogeneous structure. The gelation was highly dependent on frozen storage temperature in the range ‐10 to 14°C, but there was no appreciable difference in the range ‐14 to 24°C. When yolk was maintained motionless and supercooled at ‐10°C and ‐12°C for 23 hr, no change in the complex modulus, G*, was observed, but there was a considerable increase when yolk was disturbed and became frozen at the same temperatures for the same time.
Surimi‐Starch Interactions Based on Mixture Design and Regression Models
Authors: YOON WON B. , PARK JAE W. , KIM BYUNG Y.
Published: July 2006

Interaction effects of starch mixtures within surimi gels were investigated by modified distance‐based design and analyzed by linear and nonlinear backward regression models. Nonlinear regression model showed highly significant interaction terms of starch‐surimi, starch‐water, and starchstarch. The response trace plot revealed that shear stress and shear strain were quite sensitive to changes in amounts of starch components. Optimum solution with combinations of various starches, surimi, and water was provided using linear and nonlinear programming.
Color of Minimally Processed Potatoes as Affected by Modified Atmosphere Packaging and Antibrowning Agents
Authors: GUNES GURBUZ , LEE CHANG Y.
Published: July 2006

Minimal processing of potatoes was studied by using different treatments of cut potatoes in combination with modified atmosphere packaging. Different packaging materials and peeling methods were evaluated. An L‐cysteine (0.5%) and citric acid (2%) mixture prevented browning of potatoes effectively. Active modification of the atmosphere inside the package was necessary to achieve extended shelf‐life. Nitrogen flushing was more effective than other gas treatments with a highly permeable multilayered polyolefin packaging material. Hand peeling and lye peeling resulted in better quality, but abrasion peeling was undesirable for fresh potatoes. The shelf‐life of the minimally processed products could be extended to nearly 3 wk under refrigerated storage.
Spray Drying, Freeze Drying, or Freezing of Three Different Lactic Acid Bacteria Species
Authors: TO BRIAN C. S. , ETZEL MARK R.
Published: July 2006

Lactococcus lactis ssp. cremoris D11, Lactobacillus casei ssp. pseudo‐plantarum UL137, and Streptococcus thermophilus CH3TH, were separately frozen, freeze dried or spray dried, and tested for survival and lactic acid production before and after processing. Virtually all cells survived freezing. Of the survivors, 60 to 70% survived the dehydration step of freeze drying. In contrast to freezing and freeze drying, spray drying caused considerable delay in lactic acid production and reduction in survival. After spray drying, survival was greatest for S. thermophilus and lowest for Lc. cremoris.
Exopolysaccharide Production from Lactic Acid Bacteria Isolated from Fermented Foods
Authors: LUDBROOK K.A. , RUSSELL C.M. , GREIG R.I.
Published: July 2006

Isolates of lactic acid bacteria were obtained from non‐dairy fermented foods (Mettwurst salami, Prosciutto ham and black olives). Their species were identified and they were investigated for their ability to produce exopolysaccharides. A reference yoghurt culture (Streptococcus thermophilus) and an exopolysaccharide producing isolate (Leuconostoc mesenteroides ‐ Isolate 3) were grown in mESM broth under aerobic conditions at 25°C. They produced up to 600 mg/L and 530 mg/L of exopolysaccharide, respectively. Viscosities of the final fermentation broths were much higher in comparison to the isolated exopolysaccharide solutions. The addition of whey protein concentrate (0.2% w/v) to the extracted exopolysaccharides slightly increased the viscosity of the solutions.
Survival and Growth of Salmonella hadar on Minimally Processed Cabbage as Influenced by Storage Abuse Conditions
Authors: PIAGENTINI ANDREA M. , PIROVANI MARiA E. , GÜEMES DANIEL R. , DI PENTIMA JORGE H. , TESSI MARiA A.
Published: July 2006

Shredded, washed and centrifuged cabbage was packaged in monooriented polypropylene (OPP) bags, inoculated with Salmonella hadar and stored 10 days at 4°C, 12°C and 20°C. Microbiological, appearance, odor and headspace gas analysis were evaluated throughout storage. S. hadar and mesophilic aerobic and psychrotrophic microorganism growth was affected by storage time and temperature. S. hadar counts were lower (p<0.05) at 4°C than at 12°C and 20°C. The score ratings for general appearance, wilting, browning and off‐odor showed that all samples were commercially acceptable. Results indicated that S. hadar could survive and proliferate on minimally processed cabbage, thereby posing a potential hazard to consumers.
Oxymyoglobin and Lipid Oxidation in Phosphatidylcholine Liposomes Retarded by α‐tocopherol and β‐carotene
Authors: YIN MEI‐CHIN , CHENG WEN‐SHEN
Published: July 2006

An n‐3 fatty acid‐constructed oxymyoglobin liposome model was used to study the effects of 10 μM α‐tocopherol and/or various concentrations of β‐carotene on oxymyoglobin and lipid oxidation. Oxidation was delayed by α‐tocopherol or β‐carotene treatments alone (p < 0.05). β‐Carotene at 1.5 μM and 2μM caused greater delay in oxymyoglobin oxidation than α‐tocopherol (p < 0.05). For lipid oxidation inhibition, 2 μM β‐carotene was similar in effect to α‐tocopherol. With α‐tocopherol plus 1.5 or 2 μM β‐carotene, greater oxidation delaying effect resulted for both oxymyoglobin and lipid oxidations than with 1.5 or 2 μM β‐carotene treatment alone (p < 0.05).
Xanthan Gum Effects on Solubility and Emulsification Properties of Soy Protein Isolate
Authors: XIE Y.R. , HETTIARACHCHY N.S.
Published: July 2006

The effect of xanthan gum (XG) on solubility and emulsifying properties of soy protein isolate (SPI) was evaluated. The solubility of SPI was increased by addition of XG (p < 0.05). The emulsifying activity of SPI‐XG was 4 times higher than that of SPI or XG alone (p < 0.05) and similar to that of bovine serum albumin (BSA) (P > 0.05). The emulsifying stability of SPI‐XG dispersions was respectively 3 and 2 times higher than that of SPI and BSA (p < 0.05). The solubility and emulsifying properties of SPI‐XG dispersions were stable over a wide range of pH (3.0 to 9.0), ionic strength (0.1 to 1.0M NaCl), and heat (85°C, 1 hr).
Rheological Method for Kinetics of Drainage and Disproportionation of Soy Proteins Foams
Authors: CARP D.J. , WAGNER J. , BARTHOLOMAI G.B. , PILOSOF A.M.R.
Published: July 2006

The effect of soy protein (SP) concentration and denaturation on foaming properties was investigated. To measure drainage and disproportionation rates, a special method was based on measurements of time dependency of foam viscosity. Foam expansion reached a maximum at 3% protein concentration for denatured and 5% for native SP. Rates of drainage and disproportionation were greatly decreased by increasing protein concentration due to increased liquid viscosity (drainage) and to lowering of surface tension (disproportionation). Denaturation of SP increased foam expansion and decreased rate of drainage over the concentration range but lowered rate of disproportionation at > 4% protein.
Thermal Gelation in Relation to Binding of Bovine Serum Albumin‐Polysaccharide Systems
Authors: CAI R. , ARNTFIELD S.D.
Published: July 2006

Thermal gelation of bovine serum albumin (BSA)‐sodium alginate, BSA‐pectin and BSA‐methyl cellulose systems in relation to binding was studied using rheological testing, turbidimetric analysis and gel filtration. Two electrostatic binding mechanisms, distinguished by particle and chain segment binding models were found in BSA‐anionic polysaccharide systems. Particle binding resulted in poor gelation properties. Positive effects on gelation were found when conditions favored the chain segment binding model. Mechanisms for gelation‐binding relationships were hypothesized. No evidence of binding was found in the BSA‐methyl cellulose system, which generally exhibited the combined gelation properties of the individual components.
Low Frequency Ultrasonics for Texture Measurements in Cooked Carrots (Daucus carota L.)
Authors: NIELSEN M. , MARTENS H.J.
Published: July 2006

The use of low frequency ultrasound for texture evaluation of carrots cooked at 100°C for 0 to 15 min was examined. Uniaxial compression, microscopy and analyses of density and dry matter were used to provide comparative results for evaluating relationships between texture and ultrasonic parameters. During the first minutes of cooking the sound velocity (v) decreased and a positive correlation was found between compressive Young's modulus (Ecy) and sound velocity (v). During extended heating, sound velocity (v) increased and attenuation (α) decreased as a result of changes in mechanical properties and air and water content of the tissue.
Color and Cloud Stabilization in Cloudy Apple Juice by Steam Heating During Crushing
Authors: GENOVESE D. B. , ELUSTONDO M. P. , LOZANO J. E.
Published: July 2006

Steam heating of crushed apples in the range 65–70°C for 15 to 20 sec controlled enzymatic browning and effectively stabilized cloudiness. Particles in fresh pressed cloudy apple juice were 3 mm but after 15 min of centrifugation at 4200 × g almost all particles had a diameter of 1 mm, and cloud could be considered stable. Median and modal diameters were virtually coincident, suggesting a symmetrical distribution. The specific surface area of the cloudy juice particles was 50 mm2/g and no agglomeration occurred.
Extraction and Functional Properties of Barley β‐Glucan as Affected by Temperature and pH
Authors: TEMELLI FERAL
Published: July 2006

Barley is high in β‐glucan, a soluble fiber component. Effects of extraction temperature (40 55 C) and pH (7.0 10.0) on recovery, purity and functional properties of β‐glucan were investigated on whole Condor barley flour. At pH 7.0, 8.0 and 55°C, 86.5% of the β‐glucan in the feed flour was recovered in the gum product with 89.1% (d.w.b.) purity. β‐Glucan content increased (p < 0.05) with temperature but not with pH. Apparent viscosity of 1% (w/v) dispersions of β‐glucan gum from pH 7.0 increased (p < 0.05) with extraction temperature at constant shear rate and viscosity decreased slightly with increasing shear rate. Whippability and foam stability of gums from pH 8.0 and 45°C were maximum. Emulsions prepared with β‐glucan gum from pH 7.0 and 55@c were 63% stable after centrifugation. Barley β‐glucan shows great potential as a thickener or stabilizer.
Prediction Equations for Gases in Flexible Modified‐Atmosphere Packages of Respiring Produce are Different Than Those for Rigid Packages
Authors: TALASILA P. CHOWDARY , CAMERON ARTHUR C.
Published: July 2006

Total pressure generally decreases in a sealed rigid package containing respiring produce, whereas total pressure is essentially constant and free volume decreases in a flexible package. We found that predicted O2, CO2, and N2 partial pressures were different for similarly designed (same surface area, thickness, film permeabilities and produce mass) flexible and rigid packages at “quasi steady state” and steady state, respectively. Predicted O2 and CO2 partial pressures were slightly higher in a flexible package than in a rigid package and were a function of the film permeability ratio of N2 to O2 and of CO2 to O2. They also related to the ratio of product CO2 production rate to O2 uptake rate, target steady‐state O2 partial pressure, and respiration characteristics. Differences were slight for films such as low‐density polyethylene.
Fractionation of Lactoperoxidase and Lactoferrin from Bovine Whey Using a Cation Exchange Membrane
Authors: CHIU CLOVIS K. , ETZEL MARK R.
Published: July 2006

A microporous membrane containing immobilized sulfonic acid moieties was used for the rapid fractionation of the cations lactoperoxidase (LP) and lactoferrin (LF) from whey. The breakthrough curves of LP and LF, the LP activity and LF concentration in the elution peaks for different whey loading volumes, and the stability of membrane performance over repeated cycles of loading and elution were measured. Recovery was unaffected by an 8‐fold scale‐up exercise and repeated cycling, and was 73–6% for LP and 50–5% for LF. The membrane system was more rapid, smaller in size, and used a higher flow rate than traditional bead‐based systems.
Thiamin, Riboflavin and α‐Tocopherol Retention in Processed and Stored Irradiated Pork
Authors: FOX JAY B. , LAKRITZ LEON , THAYER DONALD W.
Published: July 2006

Combination treatments for preservation of irradiated pork were investigated with respect to vitamin loss. Ground pork was prepared under nitrogen and packaged in anaerobic foil. The samples were enzyme denatured by heating before and after irradiation, then cooked and stored. Irradiation resulted in thiamin loss, but neither riboflavin nor α‐tocopherol was affected. Neither thiamin nor riboflavin was affected by heat denaturation, cooking or storage, but heating and cooking increased the measured α‐tocopherol. The lack of loss of the vitamins was attributed to the exclusion of oxygen.
Micro‐scale Method for Determining Foaming Properties of Protein
Authors: HUANG XIAOLIN L. , CATIGNANI GEORGE L. , SWAISGOOD HAROLD E.
Published: July 2006

A 5% protein suspension (4 mL) was whipped in a modified 50‐mL centrifuge tube using a tissumizer equipped with a flat‐bottom generator. Drainage time at 50% liquid weight and the weight of the foam formed/unit volume were used for calculating foam stability and foam overrun, respectively. The foaming properties of a variety of milk proteins were determined using this method. This method distinguished differences in foaming properties among the proteins. Values for overrun confirmed published results. Compared with standard methods, this method required much less sample (about 1/20) and less measuring time (about 1/5 to 1/10).
Kinetic and Thermodynamic Parameters for Heat Denaturation of Bovine Milk IgG, IgA and IgM
Authors: MAINER G. , SÁNCHEZ L. , ENA J.M. , CALVO M.
Published: July 2006

For heat denaturation of bovine milk immunoglobulins (IgG, IgA and IgM) in the temperature range 62 to 81°C, the D values were IgG > IgA > IgM at any temperature. The Z values were 6.29, 4.00 and 5.17°C for IgG, IgA and IgM, respectively. Heat denaturation of bovine milk immunoglobulins followed a reaction kinetics in the order of n= 1.5. The highest value for apparent energy of activation was observed for IgA, and the lowest for IgG. Bovine milk immunoglobulins could resist the HTST pasteurization treatment at 72°C for 15 sec without affecting their structure.
Aroma Composition of a White Wine of Vitis vinifera L. cv. Emir as Affected by Skin Contact
Authors: CABAROGLU T. , CANBAS A. , BAUMES R. , BAYONOVE C. , LEPOUTRE J.P. , GÜNATA Z.
Published: July 2006

Free and glycosidically bound flavor compounds of a white wine from cv. Emir were analyzed by GC‐MS, and 75 compounds were identified. The wine was high in volatile phenols. Skin‐contact with the juice before fermentation increased amounts of free and glycosidically bound flavor compounds. Quantities of certain compounds were significantly different between control and skin‐contact wines.
HPLC Analysis of Cabernet Sauvignon and Noble Wine Pigment Fractions
Authors: JOHNSTON TONY V. , MORRIS JUSTIN R.
Published: July 2006

Vitis vinifera cv. Cabernet Sauvignon and Vitis rotundifolia cv. Noble wines were made with different skin contact times to investigate the anthocyanin content of fractions isolated from the wines by low pressure column chromatography. The effect of acetaldehyde addition to wine was also investigated. The fractions were analyzed by a modified HPLC procedure using a 3‐solvent gradient and a C‐18 reverse phase column. Cabernet Sauvignon fractions contained different combinations of anthocyanins; Noble wine fractions contained different ratios of five anthocyanins present in the wines. These differences are hypothesized to influence the long‐term stability of the wines.
Rapid Methods for Lipoxygenase Assay in Sweet Corn
Authors: ROMERO MARISSA VILLAFUERTE , BARRETT DIANE M.
Published: July 2006

Potential methods for rapid assay of sweet corn lipoxygenase (LPO) were evaluated and compared by visual inspection. Both model system (partially purified) and vegetable (LPO extract) system studies were carried out. Model system studies indicated that LPO had maximum activity at pH 6.0 and 2.0 mM linoleic acid. Methylene blue bleaching (MBB), carotene bleaching (CB), and potassium iodide‐starch (KI‐S) methods were evaluated both spectrophotometrically and visually. Both MBB and KI‐S methods were effective for the model system. For the vegetable LPO extract systems (sweet corn and green beans), the MBB method indicated positive results for both, the CB method was not effective for either, and the KI‐S method was very effective for green beans but not for sweet corn.
Amylose and Protein Contents of Rice Cultivars as Related to Texture of Rice‐based Fries
Authors: KADAN RANJIT S. , CHAMPAGNE ELAINE T. , ZIEGLER GEORGE M. , RICHARD OLGA A.
Published: July 2006

Mixtures of short‐, medium‐, and long‐grain rice flours, defatted rice bran, salt, and water were extruded and fried to produce French fry‐like products. Amylose and protein correlated positively with instrumental measures of hardness and gumminess. Water contents of frozen and fried fries correlated negatively with hardness and gumminess. Low protein rice cultivars retained more water than high protein cultivars during extrusion followed by cooling. Amylose content correlated negatively with water content of fried fries. Fries formulated from waxy rice had hardness and gumminess comparable to commercial French‐fried potatoes, but all other fries were too hard and gummy.
Fat Bloom and Chocolate Structure Studied by Mercury Porosimetry
Authors: LOISEL C. , LECQ G. , PONCHEL G. , KELLER G. , OLLIVON M.
Published: July 2006

The structure of dark chocolate samples was analyzed by mercury porosimetry in order to determine whether the formation of fat bloom was related to the presence of pores. The influence of cocoa butter concentration and tempering conditions on porosity were determined by using samples containing 29.5 or 31.9% fat, which were under, well or over‐tempered. All Mercury porosimetry analysis confirmed the presence of a porous structure in all chocolates. Empty spaces represented about 1% of the whole volume of a well‐tempered chocolate containing 31.9% cocoa butter but made up about 4% of the over‐tempered chocolate. A well‐tempered chocolate with only 29.5% cocoa butter showed the presence of about 2% empty spaces. From these observations and gas permeability a possible model for the microscopic structure was developed.
Yield and Textural Properties of Soft Tofu as Affected by Coagulation Method
Authors: HOU H.J. , CHANG K.C. , SHIH M.C.
Published: July 2006

Soft tofu was made using two coagulants (calcium sulfate and modified nigari), three stirring speeds (137, 207, and 285 rpm), and six stirring times (5, 10, 15, 20, 25, and 30 sec). The lowest stirring speed, 137 rpm, did not coagulate the soymilk. Tofu made by the highest stirring speed (285 rpm) had a lower yield, but higher brittleness force, hardness and elasticity than tofu made at 207 rpm. Tofu made from modified nigari had lower textural parameter values than those made from calcium sulfate. Yield of tofu made from both coagulants stirred at 207 or 285 rpm decreased as stirring time increased to 30 sec. Textural properties were related to stirring time. Stirring time < 25 sec was appropriate for soft tofu making.
Thermal Inactivation of Escherichia coli O157:H7 in Cooked Turkey Products
Authors: KOTROLA JOHN S. , CONNER DONALD E. , MIKEL W. BENJY
Published: July 2006

Survival of Escherichia coli O157:H7 when heated in commercial‐type turkey products was determined. Thermal death times (TDT) were determined at 52–60°C in ground turkey with no additives, 3% fat; ground turkey with no additives, 11% fat; turkey ham batter, 11% fat; turkey frank batter, 17% fat; and turkey sausage batter, 31% fat. Mean D52‐values ranged from 44.9 to 116 min; D55‐values from 6.63 to 39.4 min; D57‐values from 2.20 to 11.7 min; D60‐values from 0.68 to 5.86 min. At all temperatures, survival of E. coli O157:H7 was greater in formulated products than in turkey meat with no additives. Greatest survival occurred in the turkey frank batter. Using our z‐value data, times to provide a 5 D kill of E. coli O157:H7 in turkey franks cooked at 60°C, 65.6°C, or 71°C would be 26, 3.1, or 0.37 min, respectively.
Sensory and Chemical Changes in Spice‐salted Herring as Affected by Handling
Authors: GUDMUNDSDÓTTIR GUDNÝ , STEFÁNSSON GUDMUNDUR
Published: July 2006

Samples of herring (Clupea harengus) were spice‐salted, using the same recipe, as partially gutted (nobbed), completely gutted or fillets. The salt uptake and the development of ripening characteristics were followed during storage at 5 ± 1°C. In fillets the salt uptake was more rapid than that in nobbed or gutted herring. The fillets lost less water than the herring and increased considerably in weight during the salting period. Fillets did not develop the characteristic ripened taste whereas the other two groups had a high intensity of ripened taste. All trial groups sampled during salting had similar texture characteristics. The general proteolytic enzyme activity at pH 8 was low in all groups, although it appeared to be slightly higher in the samples containing part of the intestines. Results indicate that the rate of salt uptake was an important regulator of ripening during spice‐salting of herring products.
Recrystallization in Model Ice Cream Solutions as Affected by Stabilizer Concentration
Authors: SUTTON ROBIN L. , WILCOX JEAN
Published: July 2006

Ice recrystallization rates in simple aqueous solutions comprising fructose and a hydrocolloid stabilizer were measured. The stabilizers were an enzyme‐modified guar and a non‐gelling high methoxy pectin. The stabilizer concentration dependence of the recrystallization rates for both materials was similar in that increasing the concentration resulted in decreasing rates until a point is reached where further addition had no additional effect. That recrystallization rates were reduced by both gelling and non‐gelling stabilizers was strongly suggestive that gelation was not a requirement for recrystallization inhibition and another more specific mechanism applies, for example a weak interfacial effect such as adsorption or blocking. This behavior was also seen with locust bean gum and guar and provided further empirical evidence to support the hypothesis that stabilizers adsorb to ice crystal surfaces.
Rigor Tension Development in Excised “Rested”, “Partially Exercised” and “Exhausted” Chinook Salmon White Muscle
Authors: JERRETT A.R. , HOLLAND A.J.
Published: July 2006

Isometric rigorometry was used to study rigor tensions in “rested”, “partially exercised” and “exhausted” chinook salmon (Oncorhynchus tshawytscha) white muscle at the pre‐mortem acclimated temperature. Conservative handling and anaesthesia (AQUI‐STM) minimized pre‐mortem exercise and provided “rested” fish. Post‐mortem electrical stimulation produced “partially exercised” (180 contractions) and “exhausted” (360 contractions) muscle. A “relaxation” stress that decreased with increasing exercise was measured. The amplitude of the “relaxation” and contraction stress was the same for each treatment (F2,12= 0.24; p=0.79). Rigor contraction onset coincided with an intra‐muscular pH of 6.6 in each treatment (F2,12=0.28, p=0.76). Contraction stress abatement coincided with an “ultimate” pH of 6.2 in each of the treatments (F1,12=0.05; p=0.83).
Gibberellic Acid and CO2 Additive Effect in Retarding Postharvest Senescence of Parsley
Authors: LERS AMNON , JIANG WEIBO , LOMANIEC ELLA , AHARONI NEHEMIA
Published: July 2006

We studied the effect of CO2 and gibberellic acid (GA3) on postharvest senescence of parsley (Petroselinum crispum Mill.) and on ethylene induced senescence. GA3 or CO2 treatment retarded, with a similar efficiency, chlorophyll and protein degradation, amino acids accumulation and respiration rate. Treatment with GA3 and CO2 together resulted in an additive senescence retarding effect. The promoting effect of ethylene on senescence could be retarded with either CO2 or GA3. Thus, GA3 and CO2 could provide an effective means for maintaining fresh produce quality in parsley.
Textural Properties of Pressure‐Induced Gels of Food Proteins Obtained under Different Temperatures including Subzero
Authors: DUMOULIN M. , OZAWA S. , HAYASHI R.
Published: July 2006

High‐pressure‐induced gelation of ovalbumin, egg yolk and soy protein was studied by pressurization up to 500 MPa for 30 min at ‐20 to 50°C; hardness, cohesiveness and gumminess of the gels were compared to those of gels obtained by heating at 100°C for 10 min. In the range ‐5 to 50°C, ovalbumin gelation showed a minimum at 25°C at all pressures applied. Operating at low temperatures allowed a reduction in pressure required to provide rather hard gels. With egg yolk and soy protein, gelation effectiveness progressively and continuously decreased with decreasing temperatures; the decrease was sharper with egg yolk.
High‐Pressure‐Freezing Effects on Textural Quality of Chinese Cabbage
Authors: FUCHIGAMI MICHIKO , KATO NORIKO , AITERAMOTO
Published: July 2006

Differences in texture and histological structure of Chinese cabbage (midribs) pressurized at room temperature or ca. ‐20°C were investigated. Use of rising pressure at room temperature enhanced de‐esterification of pectin in midribs and increased firmness and rupture strain. When samples were frozen at 100 MPa (ice I formed) and at 700 MPa (ice VI), rupture strain increased. However, texture of samples frozen at 200 MPa (liquid), 340 MPa (ice III), 400 MPa (ice V) was comparatively intact. Release of pectin and histological damage in midribs frozen at 200 and 340 MPa were less than midribs frozen at 100 and 700 MPa. High‐pressure‐freezing was more effective in improving both texture and histological structure than freezing (‐30°C) at atmospheric pressure. However, texture of high pressure‐frozen midribs (pliant) was greatly different from raw midribs (crisp).