bluuebunny/crossref_metadata_2025 huggingface dataset:
Time‐Intensity Methodology for Beef Tenderness Perception
Authors: DUIZER L.M. , GULLETT E.A. , FINDLAY C.J.
Published: August 2006

The Time‐Intensity technique for measuring tenderness of bovine psoas major, longissimus dorsi, semitendinosus and shank was assessed. From the Time‐Intensity curve, the Duration and area parameters (Increase and Decrease Area and Area Under the Curve) were most useful for sample separation. Using various Time‐Intensity curve parameters, panelists were classified according to their perception of tenderness, with two clusters identified. A comparison of line scale results of force to chew and time to chew to the Time‐Intensity results showed that comparable tenderness measurements were obtained by the two tests.
Procedure for Soluble Collagen in Thermally Processed Meat Products
Authors: EILERT S. J. , MANDIGO R. W.
Published: August 2006

Methods to determine the extent of collagen solubilization during thermal processing in a product such as frankfurters may not be accurate. We modified existing procedures to separate soluble collagen from thermally processed meat samples without solubilizing more collagen. Water bath temperatures (36, 40, 44, 48, 52 and 56°C) and times (5, 10 and 15 min) were studied in a complete factorial design. Soluble collagen increased up to 48°C and 10 min, leveling off beyond that. In a 48–52°C water bath 10–15 min was sufficient to separate soluble collagen from thermally processed meat products without solubilizing more.
Microbiological Safety of Cooked Beef Roasts Treated with Lactate, Monolaurin or Gluconate
Authors: STILLMUNKES A.A. , PRABHU G.A. , SEBRANEK J.G. , MOLINS R.A.
Published: August 2006

Beef roasts were pumped with sodium lactate, glycerol monolaurin or sodium gluconate and inoculated with Clostridium sporogenes and Listeria monocytogenes either internally or on external (surface) locations. Microbiological evaluations were conducted during simulated wholesale (2°C), retail (7°C) and consumer storage (10°C) and after simulated mishandling (25°C). Sodium lactate resulted in effective inhibition of pathogens at concentrations up to 3.5%. Glycerol monolaurin was less effective than sodium lactate. Sodium gluconate did not provide significant control of these pathogens. No chemical or quality effects of these compounds occurred on the beef roasts except a lower pH and increased purge caused by monolaurin.
HPLC Quantitation of Alginate or Pectin Added to Lean Ground Pork
Authors: ROURKE T. J. , CLARKE A. D. , BAILEY M. E. , HEDRICK H. B.
Published: August 2006

A method was developed to isolate and quantify uranic acid(s) of alginate or pectin added at various concentrations to lean (5–7% crude fat) ground pork. The method used an Aminex HPX‐87‐H+ column, isocratic 0.009N H2SO4 eluent and ultraviolet detection. For regression equations derived from mean uranic acid concentrations to predict percentage of alginate or pectin, R2 values were 0.99 for total uranic acids (alginate) and 0.97 for galacturonic acid (pectin). Reproducibility was 84% for alginate and 94% for pectin contents. Recoveries were: alginate 85% and pectin 80%.
Rheological Properties of Mozzarella Cheese Filled with Dairy, Egg, Soy Proteins, and Gelatin
Authors: HSIEH YIN LIANG , YUN J. JOSEPH , RAO M. ANANDHA
Published: August 2006

The Rheological behavior of mozzarella cheese filled with various proteins (whey protein, caseinate, egg white, soy protein isolate, gelatin) incorporated was determined by uniaxial compression at 10°C and the effect of temperature (10°C−60°C) by dynamic measurement. Mozzarella cheese with whey protein, caseinate, egg white, and soy protein isolate showed significant water retention during heating. Among the proteins, soy protein isolate induced the strongest gel network structure with mozzarella cheese. All proteins altered the viscoelastic properties of mozzarella cheese.
Flavor Constituents of Aqueous Fraction Extracted from Comte Cheese by Liquid Carbon Dioxide
Authors: ROUDOT‐ALGARON F. , LE BARS D. , EINHORN J. , ADDA J. , GRIPON J.C.
Published: August 2006

Isolation, purification and identification of some low‐molecular‐weight compounds from a water‐soluble extract of Comté cheese was achieved. We used liquid CO2 extraction, subsequent fractionation (by gel permeation and reserve‐phase HPLC) and mass spectometry. Major constituents were N‐acyl amino acids (N‐acetyl methionine, N‐propionyl methionine, N‐propionyl leucine, N‐propionyl phenylalanine), dike‐topiperazines (cyclo(Pro‐Pro), cyclo(Pro‐Val), cyclo(Pro‐Phe), cy clo(Pro‐Leu), cyclo(Pro‐Ala)) and non‐peptide compounds (theo‐bromine, 4‐methyl‐t‐thiazoleethanol, uracil, (5–6)dihydro‐uracil, thymine). These compounds were synthesized and tasted. Most were bitter. N‐propionyl methionine had a cheese flavor but was not detected when added to a simulated cheese at 180 mg/L.
Composition and Gel‐forming Properties of Vacuum‐evaporated Liquid Egg White
Authors: CONRAD K.M. , MAST M.G. , MAC NEIL J.H. , BALL H.R.
Published: August 2006

Liquid egg‐white was evaporated under vacuum (4.7 kPa) in a water‐jacketed vessel to produce a concentrated, liquid egg white product. Three water‐jacket temperatures (40, 50 and 60°C) and four processing times (0, 30, 45 and 60 min) were used. For the 60°C, 60‐min treatment, solids content increased (p≤0.05) from 11.5% to 21.8%. Concentration did not affect (≥0.05) true gel strain but gel shear stress increased (p≤0.05) with increased solids concentration.
Denaturation of Lactate Dehydrogenase During Spray‐Drying of Bovine Plasma
Authors: MATZINOS PANAGIOTIS D. , HALL GEORGE M.
Published: August 2006

Denaturation kinetics of lactate dehydrogenase (LDH) during spray‐drying and heating of bovine plasma showed the free energy of denaturation was constant about 100 kJ/mol. Protein denaturation was investigated by polyacrylamide gel electrophoresis and solubility. At low outlet drying temperatures LDH denaturation was low and powders were completely soluble. At high outlet temperatures LDH denaturation was high and associated with powder insolubility. Electrophoretic patterns of dried samples showed differences from raw plasma at high outlet temperatures, perhaps due to production of soluble aggregates. However, LDH was not a general index of heat denaturation in spray‐drying.
Disulfide Bond Formation Affects Stability of Whey Protein Isolate Emulsions
Authors: McCLEMENTS D.J. , MONAHAN F.J. , KINSELLA J.E.
Published: August 2006

The viscosity and degree of flocculation of 20 wt% n‐hexadecane oil‐in‐water emulsions stabilized by whey protein isolate (1 wt% WPI in 0.05M phosphate buffer, pH 7.0) increased as the emulsions aged. These effects were reduced when N‐ethylmaleimide, a sulfhydryl blocking agent, was added to the emulsions immediately after homogenization, but were not completely eliminated. Gel electrophoresis (SDS‐PAGE) showed an increase in the extent of intermolecular disulfide bond formation between proteins absorbed at the droplet interface with time. Floes were probably formed initially by noncovalent bonding or bridging flocculation, and then stabilized by disulfide bonds between proteins absorbed to different droplets.
Thermal Inactivation Kinetics of Wheat Germ Lipoxygenase
Authors: BHIRUD PRAKASH R. , SOSULSKI F.W.
Published: August 2006

Thermal inactivation curves for wheat germ lipoxygenase (LPO) in partially purified and crude extracts were determined in capillary tubes at 60–68°C. The biphasic curves fitted a two‐fraction first order model suggesting the presence of 2 groups of isozymes. At 60°C, the inactivation rate constants were 9.112 × 10−‐5 set−1 and 9.174 × 10−‐6 set−1 respectively, for thermolabile phase I and thermostable phase II in the partially purified extract, a difference of one order of magnitude. For the temperature change from 60 to 68°C, the rate constants increased by three orders of magnitude, implying a very high sensitivity (for LPO inactivation in partially purified extract ΔH‡= 646261 J.mole−1, ΔS‡= 1619 J.mole−1.K−1 for phase I, ΔH‡= 546099 J.mole‐l, ΔS‡= 1298 J.mole−1.K‐1′ for phase II) to heat by both phases, although phase I was clearly the least stable.
Anthocyanin Composition of Red Raspberry Juice: Influences of Cultivar, Processing, and Environmental Factors
Authors: BOYLES MATTHEW J. , WROLSTAD RONALD E.
Published: August 2006

The anthocyanin and anthocyanidin pigment profiles of 46 authentic red raspberry juice samples were determined by HPLC. Total anthocyanin pigment content and percent polymeric color were also determined. This generated a database incorporating influences of cultivar, geographic origin, maturity, processing, and mold contamination. Cultivars exhibited characteristic patterns distinguished by quantitative rather than qualitative differences. Total pigment ranged from 4 to 1,102 mg/L. Commercial red raspberry juice concentrates (14) were also analyzed. Two were shown to be adulterated because of the presence of delphinidin glycosides. Three samples contained high amounts of polymerized pigments, indicating a history of processing or storage abuse.
Predicting Protein Functionality with Artificial Neural Networks: Foaming and Emulsifying Properties
Authors: ARTEAGA G.E. , NAKAI S.
Published: August 2006

Using physicochemical properties of 11 food‐related proteins, artificial neural networks (ANN) were developed for predicting foam capacity and stability and the emulsion activity index. The prediction accuracy of ANN was compared to that of principal component regression (PCR) models. ANN had better prediction ability than PCR, especially after cross‐validation. For foam stability, PCR did not generate a significant model. ANN and PCR models indicated that fluorescence probe hydrophobicity (measured using cispsrinaric acid) and other properties, such as viscosity, surface tension and net charge were important in predicting foam capacity and stability.
ELISA Determination of Turkey Roll Endpoint Temperature: Effects of Formulation, Storage, and Processing
Authors: WANG C.H. , BOOREN A.M. , ABOUZIED M.M. , PESTKA J.J. , SMITH D.M.
Published: August 2006

Effects of refrigerated and frozen storage, salt concentration, cooking schedule and product diameter were compared on determination of minimum endpoint cooking temperature of turkey breast rolls by measuring extractable protein (EP), lactate dehydrogenase (LDH) activity and LDH concentration by sandwich enzyme‐linked immunosorbent assay. LDH concentration differed in rolls processed to 70.0°C and 71.1°C, whereas EP and LDH activity did not differ at these temperatures. Salt concentration, cooking schedule and product casing diameter did not markedly influence LDH concentration. LDH content of uncooked rolls decreased during frozen storage. A maximum concentration of 0.31 μg LDH/g meat indicated proper processing.
1H‐NMR Study of Cholesterol Autooxidation in Egg Powder and Cookies Exposed to Adverse Storage
Authors: FONTANA A. , ANTONIAZZI F. , CIAVAlTA M.L. , TRIVELLONE E. , CIMINO G.
Published: August 2006

The level of cholesterol oxides depends on the production and storage conditions for food. We studied the effect of prolonged storage, heat, and diffuse daylight on spray‐dried egg powder and cookies containing large amounts of cholesterol. The cholesterol oxides were isolated by chromatographic procedures, and were identified by recording 1H‐NMR spectra of selected HPLC fractions. Autooxidation was quite slow when the sample was stored in a freezer at — 20°C. Diffuse daylight increased the amounts of β‐epoxide of cholesterol, whereas heating caused a sharp increase in C‐7 oxidized cholesterol derivatives. Extent of cholesterol oxidation depended on storage conditions.
Relation Between In Vitro Availability of Minerals and Food Composition: A Mathematical Model
Authors: WOLTERS M. G. E. , DIEPENMAAT H. B. , HERMUS R. J. J. , VORAGEN A. G. J.
Published: August 2006

A mathematical model was developed to describe the relative influence of phytic acid, dietary fiber components, oxalic acid, citric acid and ascorbic acid on in vitro availability of Ca, Mg, Fe, Cu and Zn. The model was based on a combination of interdependent Langmuir isotherms. Throughout a diverse set of food products (cereal products, fruits, vegetables and nuts), the mathematical model described and predicted in vitro availability of Ca, Mg, Fe and Zn well (r = 0.89, 0.87, 0.90 and 0.92 respectively). The model proved valuable in studying simultaneous effects of food components on in vitm availability of minerals and trace elements in foods. Therefore, the mathematical model should help relate in vitro simulations to in vivo experiments.
Compressive Stress‐Strain Relationships of Two Puffed Cereals in Bulk
Authors: NUEBEL CHRISTOPH , PELEG MICHA
Published: August 2006

The compressive stress‐strain relationships of two puffed cereals, rice and corn based, in bulk were determined using a Universal Testing Machine. The general sigmoid shape of the relationship could be described by a four parameter empirical model originally developed for cellular solids. Jaggedness could be expressed in terms of an apparent fractal dimension and/or the mean magnitude of the power spectrum determined using the Fast Fourier Transform. Both measures as well as a particular parameter of the empirical model were sensitive indicators of the changes in the stress‐strain relationships resulting from exposure to different relative humidities. Although the stress strain relationship, especially of dry samples, had an irregular, irreprodu‐cible shape, the magnitude of the two roughness measures was highly reproducible.
Permeability and Mechanical Properties of Cellulose‐Based Edible Films
Authors: PARK H.J. , WELLER C.L. , VERGANO P.J. , TESTIN R.F.
Published: August 2006

Factors affecting barrier properties [oxygen permeability (OP) and water vapor permeability (WVP)] and mechanical properties [tensile strength (TS) and elongation (E)] were investigated for methyl cellulose (MC) and hydroxypropyl cellulose (HPC) films. OP, WVP and TS of MC and HPC films increased as the molecular weight (MW) of the cellulose increased. E of MC films increased as MW increased, but E of HPC films was highest for the intermediate MW of 370,000. OP, WVP and TS of MC films were not a function of thickness, but E slowly increased as film thickness increased. OP and WVP of HPC films were not relatable to film thickness, but TS and E of HPC films slowly increased as film thickness increased. TS decreased and E increased for both film types as concentration of plasticizers was increased. Plasticizers enhanced or retarded OP and WVP of cellulose‐based films, depending on their concentrations.
Suitability of Plastic Films for Modified Atmosphere Packaging of Fruits and Vegetables
Authors: EXAMA A. , ARUL J. , LENCKI R.W. , LEE L.Z. , TOUPIN C.
Published: August 2006

Suitability of plastic films in standard configurations to maintain modified atmospheres was evaluated for common fruits and vegetables. Most films did not result in optimal O2 and CO2 atmospheres, especially when produce had high respiration. Produce with low and medium respiration could be matched with films considering O2 permeability requirements alone. MA packaging systems designed to produce optimal oxygen at suitable temperatures could have complications from transient temperature increases during storage and/or transportation. Respiration rates of fruits and vegetables increase more with temperature than do gas permeabilities of films. Higher than optimum temperatures could cause anoxia and seriously damage produce. More permeable gas pathways and temperature compensation to equalize Q10 values are needed for MA packaging systems to timction effectively.
Multiresponse Optimization Minimizes Salt in Natural Cucumber Fermentation and Storage
Authors: GUILLOU ANNE A. , FLOROS JOHN D.
Published: August 2006

Response surface methodology was used during natural cucumber fermentation and storage to quantitatively determine effects of NaCl (0–10%), CaCl2 (0–0.4%) and potassium sorbate (0–0.4%) on brine pH, cucumber texture and microbial (yeast/mold) contamination. Multiresponse optimization methods (conventional and improved graphical methods, extended response surface procedure and desirability function approach) were employed to minimize use of NaCl. Cucumbers fermented and stored in brines containing ∼3% NaCl, 0.28% CaCl, and 0.3% potassium sorbate were predicted to exhibit vigorous fermentation, be free of yeast/mold contamination, and maintain good firmness after 6 mo storage. Predicted results were experimentally confirmed.
Absorbability of Calcium From Common Beans
Authors: WEAVER C.M. , HEANEY R.P. , PROULX W.R. , HINDERS SM. , PACKARD P.T.
Published: August 2006

Absorption of calcium from white, red, and pinto beans, labeled with 45Ca, was measured in 24 women in a three‐way randomized design using a calcium load of 72 mg and milk as the referent. Fractional absorption for the three beans averaged 0.219 ± 0.047 and did not differ by type. Milk calcium absorption at the same load was more than two times higher, 0.451 ± 0.088 (P < 0.001). Oxalate content averaged 0.34%, and phytate averaged 1.7%, a stoichiometric excess relative to calcium. To evaluate the relation of phytate to reduced absorbability, labeled pinto beans were pre‐treated with phytase and fed to 10 subjects. Fractional absorption rose, averaging 0.318 ± 0.071, (P <0.01 vs. untreated beans), but was significantly below that of milk. The difference was partly accounted for by phytate, with the remainder probably due to relatively high oxalate.
Low‐dose Gamma Irradiation and Refrigerated FStorage in vacua Affect Microbial Flora of Fresh Pork
Authors: THAYER D. W. , BOYD G. , JENKINS R. K.
Published: August 2006

Vacuum‐packaged ground fresh pork samples absorbed gamma radiation doses of 0. 0.57. 1.91. 3.76. 5.52. or 7.25 kGv at 2°C. Samolcs were analyzed after 1, 7, 14, 21, 28,‘or 35 days itorage at 2°C’for presence and number of aerobic and anaerobic mesophiles and endospore formers, and aerobic psychrotrophs. Conventional plate counts did not detect surviving microflora in any sample that received an absorbed dose of 1.91 kGy or higher, even after refrigerated storage for up to 35 days. The microflora in the control were predominantly Gram‐positive for the first 21 days; however, Serratia predominated at 28 and 35 days. Staphylococcus, Micrococcus, and yeast species predominated in samples that received 0.57 kGy.
Porcine Aminopeptidase Activity as Affected by Curing Agents
Authors: TOLDRÁ FIDEL , CERVERÓ M‐CARMEN , PART CAROLINA
Published: August 2006

The effect of common curing agents (salt, nitrate, nitrite, ascorbic acid and glucose) on porcine muscle leucyl, arginyl, alanyl, pyroglu‐tamyl and tyrosyl hydrolyzing activities was studied. Salt, ascorbate and nitrite had inhibitory effects on most enzyme activities. All activities decreased as salt increased (to 1.25 M) and/or water activity decreased (from 1.00 to 0.81). Nitrite inhibited only alanyl, pyroglu‐tamyl and tyrosyl hydrolyzing activities. An in‐vitro study using model conditions of three stages of dry‐curing of ham, revealed that leucyl hydrolyzing activity may be important through the complete process. Other enzymes may also be involved in later stages of curing but are less important.
Edible Meat Casing from Reconstruction of Collagen‐Elastin Matrix
Authors: TAKAHASHI KOJI , HATTORI MAKOTO
Published: August 2006

Pepsin‐solubilized clastin (PSE) was prepared from insoluble elastin (IE) preparation by digesting it with pepsin [IE:pepsin, 100:1(w/w)] at 25°C for 5–30 hr prior to dialyzing against water and lyophilizing. PSE showed amino acid compositions similar to that of IE and relative molecular weight (Mr) of 6–640 × 103. PSE accelerated the matrix reconstruction of pepsin‐solubilized collagen (PSC) and reduced the rcdissolution of the PSC matrix under several solvent conditions. PSE clcvatcd the matrix thermal dcnaturation temperature from about 50°C to 55°C, leading to decreased breaking strength and reduced elongation of the PSC film, as compared with the control.
Anhydrous Milk Fat Fractionation with Continuous Countercurrent Supercritical Carbon Dioxide
Authors: BHASKAR A.R. , RIZVI S.S.H. , SHERBON J.W.
Published: August 2006

A continuous pilot‐scale supercritical carbon dioxide system was designed and built for separation and fractionation up to 400 g/hr of anhydrous milk fat. This fat was separated into five fractions (S1‐S5) in the pressure range 24.1–3.4 MPa at 40–75°C. The solvent/feed ratio was 62 with extraction yield 78 wt%. The short‐chain (C4‐C8) and medium‐chain (C10‐C12) fatty acids increased from S1S5. The long‐chain and unsaturated fatty acids (C14‐C18) decreased gradually from S1‐S5. The triglycerides followed the same trend as fatty acids. Cholestrol content decreased by 51% and β‐carotene concentration increased by 145% in the raffinate (S1).
Soluble and Lipid‐Bound Calcium and Zinc During Processing of Infant Milk Formulas
Authors: MICHEL I. , LAVIGNE C. , DESROSIERS T.
Published: August 2006

Samples were withdrawn during the manufacture of infant formulas to determine steps which may affect soluble and lipid‐bound Ca and Zn, which were estimated after centrifugal separation of in vitro digested samples. Pasteurization did not significantly reduce solubility of Ca and Zn. Blends forewarmed at low temperature contained a smaller proportion of soluble Ca than skim milk, but Zn was not affected. Forewarming at high temperature reduced solubility of Ca. The solubility of Ca and Zn was lower in sterilized and spray‐dried formulas than in blends forewarmed at low temperature. Though initial Ca and Zn levels were greater in infant formulas than in human milk, percentages of soluble Ca and Zn were not higher.
Optimizing Processing Conditions for Chemical Peeling of Potatoes using Response Surface Methodology
Authors: GARROTE RAÚL L. , COUTAZ VÍTOR R. , LUNA JULIO A. , SILVA ENRIQUE R. , BERTONE RICARDO A.
Published: August 2006

Using Response Surface Methodology the effects of NaOH concentration (4–20%), process temperature (55–95°C) and time (1–7 min) was determined on the yield, peeling quality, unpeeled skin and total usage of NaOH. Also evaluated were titratable NaOH in the potato tissue, NaOH penetration and “heat ring” depths during one stage chemical peeling of potatoes (Huincul variety). The best peeling quality, maximum yield and minimum total usage of NaOH was obtained for the following ranges: concentration, 11–13%, time 5–5.70 min and temperature, 90–95°C. The maximum temperature for which the “heat ring” and NaOH penetration depths were equal was 72°C where, at 20% NaOH and 7 min, peeling quality was very good and “heat ring” was absent.
Diffusion in Heated Potato Tissues
Authors: GEKAS VASSILIS , ÖSTE RICKARD , LAMBERG INGRID
Published: August 2006

Data to optimize nutrient retention during processing of potatoes were obtained by measuring loss of solutes (glucose, fructose, citric acid, potassium, calcium and magnesium) by diffusion into blanch water. Apparent diffusivities were calculated based on Fickian diffusion. Magnesium and calcium did not follow the Fickian approach with the same accuracy as the others. A hindrance factor (K), the ratio of apparent diffusivity in potato to a published value was used. The hindrance factor was calculated at reference temperature 25°C to separate preheating effects from the direct effect of temperature on diffusion coefficients. A mathematical model for K(T,t) was fitted to experimental data for each solute. All solutes showed a sharp decrease of hindrance factor in the region 50–60°C. These models showed, however, that heating of potato affected diffusivities of the solutes to different degrees. Ions had a limit solution retention in the tissue higher than glucose, fructose or citric acid.
Oil Absorption and Sensory Properties of a Snack Food from Chickpea Genotypes
Authors: SINGH U. , SEETHA R.
Published: August 2006

Among the commonly consumed grain legumes the score on general acceptability of a snack food (seviya) was the highest for that from chickpea (Cicer arietinum L.) followed by lentil, pigeonpea and green gram, whereas the oil absorption by the product was highest for lentil followed by black gram, chickpea, and green gram. Different methods of dehulling did not cause any notable effects on oil absorption of chickpea seviya. The flour particle size, starch, and protein contents significantly influenced oil absorption of seviya. The oil absorption of the product differed significantly among genotypes, but clear cut differences were not found between desi and kabuli groups of chickpea genotypes.
Substrate Specificity of Mackerel Flesh Lipopolygenase
Authors: HARRIS PETER , TALL JANICE
Published: August 2006

A lipoxygenase enzyme was found in mackerel flesh which oxidized linoleic and docosahexaenoic acids more efficiently than eicosapentaenoic or linolenic acids. Activity was inhibited by esculetin and was destroyed by boiling; 40% of activity was lost after incubation at 50°C for 10 min, and 80% after incubation at 60°C. Ultrafiltration of the crude enzyme extract with a molecular weight cut off of 10 KD showed the activity came predominantly from the higher molecular weight fraction. Results support the hypothesis that there are several different lipoxygenases located in different fish tissues.
Copper Chelation Assay For Histamine in Tuna
Authors: BATEMAN R.C. , ELDRIGE D.B. , WADE S. , McCOY‐MESSER J. , JESTER E.L.E. , MOWDY D.E.
Published: August 2006

A reported copper chelation method for histamine determination was modified for use in decomposing yellowfin tuna steaks. The assay consisted of histamine extraction with hot methanol, purification by rapid cation exchange chromatography, and addition of copper and a dye to the purified sample to form an easily visualized red complex with the histamine. This method detected histamine in the low mg% range in yellowfin tuna steaks with an accuracy comparable to the standard fluorometric histamine assay. It is an alternative to the standard assay when a visual test is desirable or a fluorometer is not available.
Gelation of Surimi by High Hydrostatic Pressure
Authors: CHUNG Y.C. , GEBREHIWOT A. , FARKAS D.F. , MORRISSEY M.T.
Published: August 2006

The effects of high hydrostatic pressure (HHP) on gel strength of Pacific whiting and Alaska pollock surimi were determined by torsion. Pacific whiting gels were made with and without 1% beef plasma protein (BPP) as protease inhibitor. HHP treated whiting (1% BPP added) and pollock gels showed greatly increased strain values at all pressure/temperature combinations compared with heat‐set controls. Stress values for the same samples were variable depending on treatment and species. A three‐fold increase in strain and stress was found for HHP treated whiting gels made without inhibitor.
Reverse‐Phase HPLC Analysis of Reference Cheddar Cheese Samples for Assessing Accelerated Cheese Ripening
Authors: FURTULA V. , NAKAI S. , AMANTEA G.F. , LALEYE L.
Published: August 2006

Applying water extracts from Cheddar cheese to an octadecyl vinyl alcohol copolymer column using a reliable auto‐sampling system provided highly repeatable HPLC patterns. Two batches of standard samples of mild, medium, sharp, and extra‐sharp and one batch of abused samples (rapidly aged under abnormal conditions) were analyzed. Principal component similarity (PCS) analysis indicated similar shifts of plots due to aging of the standard batches, while the plot for the abused batch deviated from the pathway of normal aging. PCS may be useful for analysis of accelerated ripening effects as well as finding unusual samples during quality control.
Proteose Peptones and Physical Factors Affect Foaming Properties of Whey Protein Isolate
Authors: ZHU HAIMING , DAMODARAN SRINIVASAN
Published: August 2006

Effects of peptides and nonprotein components of whey on whey protein isolate (WPI) were studied using a differential pressure method. Decay of WPI foam followed biphasic first‐order kinetics, but was affected by solution conditions. WPI foam stability exhibited two pH optima (5.0 and 8.5). Addition of 0.02–0.15M NaCl progressively decreased foaming capacity and foam stability. Addition of 0.01–0.2% proteose‐peptones caused a sharp decrease in foam stability, but did not affect WPI foaming capacity. Foam stability was increased by addition of up to 20% lactose. Removal of proteose‐peptones should greatly improve foaming properties of whey proteins.
Edible Coating Effects on Storage Life and Quality of Tomatoes
Authors: PARK HYUN J. , CHINNAN MANJEET S. , SHEWFELT ROBERT L.
Published: August 2006

Tomatoes at breaker and pink stage maturities were coated with comzein film. Color, weight and firmness changes and sensory quality were compared with noncoated tomatoes during storage at 21°C. Corn‐zein fdm delayed color change and loss of firmness and weight during storage. Shelf life was extended by 6 days with film coatings as determined by sensory evaluation.
Production of Anthocyanin from Strawberry Cell Suspension Cultures; Effects of Sugar and Nitrogen
Authors: MORI TSUKASA , SAKURAI MlEl
Published: August 2006

Production of anthocyanins was investigated, controlling sugar concentration and ratio of ammonium: nitrate in culture medium of strawberry, Fragaria ananassa cv Shikinari. Anthocyanins were produced under 8000 lux for 2 wk using calli derived from suspension cultures of leaf tissues. Yield was greatest in modified LS medium containing 5% sucrose (W/V), a ratio of NH+3 (2 mM):NO−3 (28mM), 2,4‐dichlorophenoxyacetic acid and benzyladenine. Total anthocyanin was about 15 mg/100 mL of culture medium, almost six times greater than that in MS medium. Effects of sugars were also studied using eight sugars. Cell growth and anthocyanin accumulation were enhanced by glucose, sucrose, and fructose, but anthocyanin compositions were not affected. Major anthocyanins were peonindin‐3‐glucoside and cyanidin‐3‐glucoside. Peonidin‐3‐glucoside increased with an increase in the NH+4 NO−3 ratio at nitrogen concentration 30 mM, while that of cyanidin‐3‐glucoside changed vice versa.
Kinetics of Acid Hydrolysis of Defatted Peanut Flour
Authors: WAlTANAPAT RUDEEPAN , NAKAYAMA TOMMY , BEUCHAT LARRY R. , PHILLIPS R. DIXON
Published: August 2006

The kinetics of hydrolysis of defatted peanut flour as affected by treatment at 100, 110 and 120°C in 3N and 5N HCl were determined. Rates of hydrolysis of protein and destruction of reducing sugars were rapid at 120°C and in 5N HCl. About 90% of total amino acids were released after 4 hr. The overall rate of reaction followed second‐order kinetics as monitored by the generation of free amino acids over time. This relationship was reliable for all acid and temperature treatment conditions when the extent of hydrolysis was less than 80%. The rate of hydrolysis of peanut protein was about 2.2 times faster for every 10°C increase. Hydrolysis in 3N HCl was about 2.3 times faster than in 3N HCl at the same temperature. The activation energy was =24 kcal mol−1. The rate of liberation of individual amino acids with respect to temperature and HCl concentration, however, varied.
Mathematical Model for Formation Rate and Collapse of Foams from Enzyme Modified Wheat Flours
Authors: BOMBARA N. , PILOSOF A.M.R. , AÑÓN M.C.
Published: August 2006

A zero‐order equation described the expansion rate of foams. Lower viscosity and yield values of doughs allowed an increase in rate of expansion of foams as the degree of hydrolysis increased. Foam volume was increased by enzyme hydrolysis of wheat proteins from 63 mL for untreated wheat flour to 93 mL for 36.7% DH flour. Time course of collapse was fitted by a second‐order equation suggesting that its rate was determined by coalescence between gas bubbles. The rate of collapse was enhanced by protein hydrolysis. This indicates that a high degree of gluten structure was required for maximum stability.
Volume Expansion during Hot Air Puffing of a Fat‐free Starch‐Based Snack
Authors: GURAYA H.S. , TOLEDO R.T.
Published: August 2006

Puffed volume and puffing uniformity of a fat‐free snack were investigated. Strips of drum‐dried sweet potato‐tapioca pastes were puffed 15 set at 200°C in a fluidized bed. Puffed product specific volume (SV) was related to starch gelatinization, soluble solids content, initial moisture and method of half‐product preparation. SV was maximum (490% increase) and most uniform (3.94% coef. of variation) when 70% moisture paste was drum‐dried at 100°C and 1 rpm to produce the half‐product. Starch was 93% gelatinized in this process. Soluble solids reduced nuffine by reducine starch gelatinization. Half‐product produced by sheeting dough coitaining‐ pregelatinized starch had puffed volumes which significantly correlated with starch gelatinization.
Sucrose Polyester Content in Foods by a Calorimetric Method
Authors: DRAKE M.A. , NAGEL C.W. , SWANSON B.G.
Published: August 2006

Lipids were extracted from the food sample with petroleum ether and sucrose polyesters (SPE) and triglycerides in the extract were hydrolyzed with 1N methanolic KOH for 8 min. Free sucrose was extracted with water, and quantified calorimetrically using a phenol‐sulfuric acid test. Results were compared to a standard curve from known quantities of hydrolyzed SPE. Standard curves were linear and reproducible through 90% SPE (r = 0.999).
Freeze‐cracking in Foods as Affected by Physical Properties
Authors: KIM N.‐K. , HUNG Y.‐C.
Published: August 2006

Severe mechanical damage such as cracks can occur in foods during cryogenic freezing. Ten physical properties of 22 different materials were correlated with freeze‐cracking incidence. Statistical analyses revealed that several properties correlated significantly with freeze‐cracking. This implies that freeze‐cracking depends not only on moisture content but on combinations of several properties. A set of equations based on densities and porosities was developed to predict freeze‐cracking incidence with an accuracy of 98% in noncracking products and 70% in cracking products during cryogenic freezing. In addition, susceptibility of various food commodities to freeze‐cracking was determined.
Convective Heat Transfer at Particle‐Liquid Interface in Continuous Tube Flow at Elevated Fluid Temperatures
Authors: BALASUBRAMANIAM V.M. , SASTRY S.K.
Published: August 2006

Liquid‐to‐particle convective heat transfer coefficients are useful in developing aseptic food processing systems. They were determined for continuous flow through a holding tube at 115.5°C using liquid crystal and relative velocity methods with sodium carboxymethylcellulose solution to simulate non‐Newtonian fluid characteristics. An on‐line tube viscometer was used for in situ estimation of rheological characteristics. Minimum and maximum values of hfp determined from the liquid crystal method ranged from 986 W/m20K to 2270 W/m20K, (Nusselt numbers from 26.4 to 54.6). Values from the relative velocity method ranged from 1143 to 2270 W/m20K (Nusselt numbers from 33.2 to 63.1) when using the Ranz and Marshall relation, and from 598 to 1456 W/m20C (Nusselt numbers from 13.6 to 24.1) with a flat‐plate correlation. Heat transfer coefficients increased significantly with decreasing carrier medium viscosity and decreasing particle‐to‐tube diameter ratio and increased with flow rate.
Rancidity in Selected Sites of Frozen Catfish Fillets
Authors: FREEMAN D.W. , HEARNSBERGER J.O.
Published: August 2006

Gas chromatographic volatiles and TBA values for three external fillet sites (lateral line, visceral‐side and skin‐side) and the fillet interior were compared with sensory evaluations of baked fillets to determine rancidity development. A sampling technique was developed that allowed procurement of the various fillet site tissues from whole fillets after storage at ‐20°C for up to 6 mo. The lateral line had the most rancidity while internal tissues had the least. Instrumental examination of the lateral line proved effective for predicting sensory detection of rancidity. Correlation coefficients for lateral line total volatiles and TBA values with flavor were 0.98 and 0.95, respectively.
Carcass Characteristics of Channel and Hybrid Catfish, and Quality Changes during Refrigerated Storage
Authors: HUANG Y.W. , LOVELL R.T. , DUNHAM R.A.
Published: August 2006

Channel (Ictalurus punctatus) and hybrid (channel, I. punctutus, female × blue, I. fircatus, male) catfish were harvested from the same pond. Fillets were overwrapped or vacuum‐skin packaged and stored 13 days at 4°C. Carcass characteristics, chemical, microbiological and sensory qualities were compared. No significant differences in body weight and proximate composition between the two genotypes were found. However, the visceral fat of the hybrids was significantly higher than that of channel catfish. Vacuum‐skin packaged fillets had significantly lower free fatty acid levels and psychrotrophic populations than did overwrapped fillets on the 13th day of refrigerated storage.
Stabilization of Lipids in Minced Fish by Freeze Texturization
Authors: KOLAKOWSKA ANNA , SZCZYGIELSKI MAREK
Published: August 2006

Minced meats of Baltic cod (Gadus morhua) with added krill (Euphausia superba D.), krill precipitate, or bream (Abramis brama) were freeze‐textured or frozen conventionally. Lipid composition and oxidation were analyzed after 6–8 mo storage at –20°C. Analyses included peroxide value, fluorescence, lipid classes (thin‐layer chromatography), and fatty acid composition (gas chromatography). Peroxide value was 4–9 times lower in freeze‐textured meat minces than in conventionally frozen samples. Docosahexaenoic acid (DHA) was higher, by 22% in bream minces to 80% in cod minces without additives, in all freeze‐textured minces than in conventionally frozen samples. Texturization could reduce lipid oxidation in minced fish during frozen storage.
Crayfish Hepatopancreatic Extract Improves Flavor Extractability from a Crab Processing By‐product
Authors: KIM H.R. , BAEK H.H. , MEYERS S.P. , CADWALLADER K.R. , GODBER J.S.
Published: August 2006

Incorporation of crayfish hepatopancreatic extract (CHE) improved the extraction of volatile flavor compounds and increased the extract‐ability of nonvolatile nitrogen compounds from crab hard tissue (CHT) obtained by mechanical separation of composite processing by‐product. Optimum reaction conditions for hydrolysis of CHT protein were 2 hr reaction with 1 mL CHE per 10g CHT at 45°C. Concentration of volatile flavor compounds increased significantly in CHE‐treated CHT compared with those from untreated substrate; however, dienals and aromatic hydrocarbons decreased. Pyrazines, especially 2‐ethyl‐6‐methylpyrazine and 2,3‐dimethylpyrazine, were in markedly higher concentrations due to CHE treatment.
Citric Acid and Antimicrobials Affect Microbiological Stability and Quality of Tomato Juice
Authors: BIZRI JAMAL N. , WAHEM IBRAHIM A.
Published: August 2006

Acidification, addition of dimethyl dicarbonate and a mixture of potassium sorbate and sodium benzoate and storage temperature were related to microbiological stability and quality of tomato juice. Whether iuices were acidified CDH 4.0 to 3.7) or nonacidified. dimethyl dicarbonate and sorbate/benzoate were highly effective in diminishcng mold and yeast count at 5°C and 20°C. Dimethyl dicarbonate in juices acidified to pH 3.7 and stored at 5°C was most effective in controlling plate counts, followed by sorbate/benzoate in juices acidified to pH 3.7 and stored at 5°C and 20°C. Tomato juice treated with dimethyl dicarbonate had lower amounts of ascorbic acid, total amino acids, fructose, glucose, lycopene and β‐carotene.
Kinetic Parameter Estimation for Quality Change during Continuous Thermal Processing of Grapefruit Juice
Authors: COHEN ELI , BIRK YEHUDITH , MANNHEIM CHAIM H. , SAGUY ISRAEL S.
Published: August 2006

Reaction order, activation energy (Ea) and average rate constant (kav) were evaluated by dynamic modeling for color degradation of grapefruit juice during thermal processing. Simulated aseptic conditions were: 85–135°C, 40–175 set processing time, and average velocities 5–30 cm/set. Quality was assessed by nonenzymatic browning index (NEBI) and S‐hydroxymethyl‐furfural (HMF). Average values for reaction‐order and energy of activation were: 0 and 21.4 kcal/g‐mol (NEBI) and 0.3 and 23.2 kcal/g‐mol (HMF), respectively. These values were compared with those contained in the deformed ellipsoid which define the 90% joint confidence interval of all possible parameter combinations. Based on initial and final concentrations, the method can predict effects of processing on liquid foods.
Na+ Binding as Measured by 23Na Nuclear Magnetic Resonance Spectroscopy Influences the Perception of Saltiness in Gum Solutions
Authors: ROSElT TERRI ROBERTSON , SHIRLEY LENA , SCHMIDT SHELLY J. , KLEIN BARBARA P.
Published: August 2006

Binding of Na+ in aqueous gum systems as determined by 23Na nuclear magnetic resonance (NMR) spectroscopy and its relations to perceived saltiness were examined. Two levels of NaCl (0.1% and 0.2%) were added to two concentrations (0.1% and 0.3%) of two ionic (xanthan and kappa carrageenan) and two non‐ionic (locust bean and guar) gum solutions. Saltiness perception was affected by the ionic properties of the gums. NMR transverse relaxation rates (R2, see−l) indicated Na+ was less mobile in ionic than nonionic systems. Ionic gums correspondingly suppressed saltiness perception‐ compared to nonionic gums. As Na+ increased in both ionic and nonionic systems, R2 values converged and perceived saltiness equalized. Food components that bind Na+ may suppress saltiness perception, which may be important in low‐sodium foods.
Influence of Thermal Treatment on Gelation of Actomyosin from Different Myosystems
Authors: JIMÉNEZ‐COLMENERO F. , CARECHE J. , CARBALLO J. , COFRADES S.
Published: August 2006

We analyzed the influence of temperature and heating time on rheological properties, and types of proteins involved in the gelation process of natural actomyosin from pork, chicken, and hake. At low temperatures (40–50°C) hake gels were stiffer than chicken or pork gels (due to setting); at higher temperatures (60°C), actomyosin from all three formed gels with similar rheological characteristics. Types of protein in the different fractions (analyzed by electrophoresis) were consonant with the rheological behavior of the AM gels for each heat treatment and species.
Limonene and Myrcene Sorption into Refillable Polyethylene Terephtalate Bottles, and Washing Effects on Removal of Sorbed Compounds
Authors: NIELSEN TIM J.
Published: August 2006

The sorption of two orange volatile compounds, myrcene and limonene, into refillable polyethylene terephtalate bottles, different types of polyethylene terephtalate strips, and polycarbonate strips, was studied. The bottles were washed with sodium hydroxide solutions and remaining aromas in the plastic were analyzed. Sorption continued during the 12 wks storage, but the major part was sorbed during the first week. Bottles stored at 25°C absorbed considerably more myrcene and limonene than bottles stored at 4°C. A simulated industrial washing procedure removed small amounts of the aromas but 50–80% remained in the packaging material. Polycarbonate absorbed flavors to a much larger extent than did polyethylene terephtalate.
Lactic Acid/Melanosis Inhibitors to Improve Shelf Life of Brown Shrimp (Penaeus aztecus)
Authors: BENNER R.A. , MIGET R. , FINNE G. , ACUFF G.R.
Published: August 2006

l‐Lactic acid, sodium bisulfite, and 4‐hexylresorcinol were evaluated, alone and in combination, as melanosis and microbial spoilage inhibitors on brown shrimp (Penaeus aztecus). No effect on the microbiological shelf life of treated shrimp was observed. 4‐Hexylresorcinol functioned exceptionally well as a melanosis inhibitor, alone and in combination with. l‐lactic acid. However, extensive bacterial growth was demonstrated in the 4‐hexylresorcinol dip solution during normal storage on deck, creating the potential for a heavy bacterial inoculation of shrimp during a typical dipping process. Addition of l‐lactic acid to the 4‐hexylresorcinol dip solution prevented bacterial growth in the dip solution and did not diminish melanosis inhibition.
Stability of Mackerel Surimi Prepared under Lipid‐Stabilizing Processing Conditions
Authors: KELLEHER STEPHEN D. , HULTIN HERBERT O. , WILHELM KURT A.
Published: August 2006

Surimi from mackerel whole and light muscle was prepared under conditions designed to minimize oxidation and development of rancidity. The lipid‐stabilizing procedure included early addition of both lipid‐and water‐soluble antioxidants, avoidance of added sodium chloride, and exclusion of oxygen. Surimi prepared from light muscle was stable to rancid odor development in both the raw and cooked form; gel strength was reasonably stable during frozen storage, although the color was somewhat dark. Surimi prepared from mackerel whole muscle was darker, its odor quality lower and less consistent, and its gel strength lessened more rapidly during frozen storage than surimi prepared from light muscle.
Dietary α‐Tocopheryl Acetate Contributes to Lipid Stability in Cooked Beef
Authors: LIU Q. , SCHELLER K.K. , SCHAEFER D.M. , ARP S.C. , WILLIAMS S.N.
Published: August 2006

Lipid oxidation was investigated in cooked gluteus medius from Holstein steers fed diets including four levels of α‐tocopheryl acetate (0, 250, 500 and 2,000 mg/steer daily) for 42 or 126 days. Alpha‐tocopherol (vitamin E) concentrations increased in fresh and cooked muscle due to level and duration of supplementation (P<0.01). Cooking did not affect α‐tocopherol concentration in the muscle. Dietary α‐tocopheryl acetate delayed (P<0.01) accumulation of lipid oxidation products in cooked muscle during 6 days of display at 4°. Daily supplementation of 500 mg α‐tocopheryl acetate for 126 days resulted in 3.4 μg α‐tocopherol/g cooked gluteus medius.
Meat Quality Kinetics during Beef Carcass Chilling
Authors: MALLIKARJUNAN P. , MITTAL G.S.
Published: August 2006

Kinetic models for changes in muscle pH and beef quality, based on press juice and puncture strength, were determined during beef carcass chilling. Changes in quality of Longissimus dorsi muscle during chilling were determined and modeled using reaction kinetics and Eyring's absolute reaction rate theory. The pH and press juice followed first order reaction kinetics while puncture strength did not follow any specific reaction order. Enthalpy and entropy of activation for changes in the quality indices were calculated.
Quality Maintenance of “Ready‐to‐eat” Shredded Carrots by Gamma Irradiation
Authors: CHERVIN CHRISTIAN , BOISSEAU PATRICK
Published: August 2006

Shredded carrots were either chlorinated, rinsed, and spin‐dried as in industrial processes, or irradiated (2 kGy), replacing the three steps. Several factors defining the quality of minimally processed vegetables were monitored during storage at 10°. Atmospheres inside micro‐porous plastic bags stabilized at 7–15% O2 and 10–15% CO2. Sugar levels in tissues were twice as high in irradiated samples as in chlorinated ones. Irradiation also prevented losses of orange color and carotenes. Growth of aerobic mesophilic and lactic microflora was strongly inhibited by irradiation. Sensory analysis demonstrated preferences for irradiated vegetables. Irradiation, avoiding three potential denaturing steps preserved “ready‐to‐eat” shredded carrots with better quality than those prepared by conventional industrial processes.
Bioavailability of Vitamin A in a Synthetic Rice Premix
Authors: FLORES HERNANDO , GUERRA NONETE B. , CAVALCANTI ANA CLÁJDIA A. , CAMPOS FLORISBELA A.C.S. , AZEVEDO MARIA CHRISTINA N.A. , SILVA MARÍLIA B.M.
Published: August 2006

The Relative Dose Response Test (RDR) was used to assess the bioavailability of vitamin A in a stabilized form in artificially produced rice kernels. The vitamin A proved stable to storage and cooking, and the enriched rice was nontoxic, and had the same sensory characteristics of ordinary rice. The nutrified rice, cooked with sugar and milk, was offered to 83 deprived children as the challenge dose for an RDR test. The children showed positive and negative tests in agreement with their serum retinol levels. The regression of RDR on serum retinol levels was the same as that observed when the conventional RDR test was applied.