bluuebunny/crossref_metadata_2025 huggingface dataset:
Fractionation of Rice Glutelin Polypeptides using Gel Filtration Chromatography
Authors: SNOW S.D. , BROOKS J.R.
Published: August 2006

Preparative gel filtration chromatography using Sepharose CL‐6B was utilized to obtain working quantities of dissociated rice glutelin polypeptides. Rice flour samples were extracted and fractionated using dilute Tris buffer containing either 0.5% SDS, 6M urea or 8M urea. Gel filtration under each set of extraction conditions yielded fractions containing dissociated acidic and basic glutelin polypeptides, but acidic polypeptides were more effectively separated from basic polypeptides in urea than in SDS. The presence of glutelin polypeptides in higher molecular weight aggregates under each set of buffer conditions indicated that the dissociation of these components during extraction was not complete.
Resistance to Tear: An Instrumental Measure of the Cohesive Properties of Muscle Food Products
Authors: MacNEIL J.H. , MAST M.G.
Published: August 2006

An instrument was developed to measure cohesive properties of restructured muscle foods. The device, an attachment for the Texture Test System, consists of a spiked split‐platform designed to hold a meat slice in place as the two sections of the platform are pulled apart. The force [referred to as resistance to tear (RTT)] required to tear a sample is transmitted via a transducer located at the stationary end of the split‐platform. Experiments in which fish, broiler or turkey meat patties were formulated to provide differences in cohesive properties, showed that RTT measurements were responsive to the effects of formulation manipulations and corresponded well with sensory evaluations.
Soy Proteins in Milk Replacers Identified by Immunoblotting
Authors: VENTLING B.L. , HURLEY W.L.
Published: August 2006

A method was developed for detecting soy proteins in milk replacers and infant formulas. The method is based upon polyacrylamide gel electrophoresis of proteins, electroblotting the proteins to nitrocellulose, and detection of specific proteins by immunoblotting. As little as 25 ng of total soy protein per gel lane can be detected with this method. Proteins from other plant products were detected by the method but care must be used in comparing milk replacer proteins directly to soy proteins. This method should be of value to the animal and food industries that manufacture and use milk replacers.
Compositional Analysis of Powdered Cocoa Products by Near Infrared Reflectance Spectroscopy
Authors: PERMANYER J. J. , PEREZ M. L.
Published: August 2006

Near infrared reflectance (NIR) spectroscopy was used to measure moisture, fat, and sucrose in powdered cocoa products. Spectra of a series of known samples were recorded and multiple linear regression techniques were used to relate the concentrations of each parameter to reflectance measurements at selected wavelengths. Precision and accuracy were estimated to evaluate the potential application of the NIR spectroscopy in the quality control of powdered cocoa products. Results showed that moisture, fat, and sucrose could be analyzed in powdered cocoa products by near infrared reflectance spectroscopy because good correlation coefficients and low standard errors were achieved in prediction study.
An Edible Film of Lipids and Cellulose Ethers: Barrier Properties to Moisture Vapor Transmission and Structural Evaluation
Authors: KESTER J. J. , FENNEMA O.
Published: August 2006

An edible, composite film of lipid and cellulose ethers was developed and appraised as a barrier to moisture vapor transmission. The film was comprised of a matrix of methylcellulose, hydroxypropyl meth‐ylcellulose and saturated C16 and C18 fatty acids, with a thin layer of white beeswax laminated to the surface. The edible film effectively retarded transport of moisture at water activities (aw) up to at least 0.97 and maintained good barrier properties even when the aw on the low‐humidity side of the film was relatively high. The apparent activation energy for water vapor transmission through the edible film was 14.2 ± 2.5 kcal/mole. Electron microscopy revealed the importance of lipid morphology in determining moisture resistance lipid‐base films.
An Edible Film of Lipids and Cellulose Ethers: Performance in a Model Frozen‐Food System
Authors: KESTER J.J. , FENNEMA O.
Published: August 2006

An edible, lipid‐cellulose ether composite film was fabricated and tested as a barrier to internal moisture migration in a bicomponent food product stored under abusive conditions of frozen storage (‐6.7°C for 9 wk). The product consisted of bread and a tomato‐based sauce; the film was situated at the interface of the two components. The film effectively retarded migration of moisture from the sauce to the bread during storage. As a consequence, desirable sensory properties that were related to stabilization of moisture gradients, as measured following cooking, were maintained significantly better (P < 0.05) in the presence of the film than they were in its absence.
Phosphate Type and Salt Concentration Effects on Shear Strength of and Packaging Film Adhesion to Processed Meat From a Cook‐in Packaging System
Authors: ROSINSKI M.J. , BARMORE C.R. , BRIDGES W.C. , DICK R.L , ACTON J.C.
Published: August 2006

Shear force values of product slices and adhesion at packaging film‐meat interfaces were measured for vacuum‐packaged, cook‐in‐the‐film prepared meat products. With 2.0% NaCl, phosphate addition at 0.4% increased both measures in the following order of effectiveness: sodium acid pyrophosphate > sodium tripolyphosphate > no phosphate. For NaCl effects, generally a 1% increase in concentration in the range of 0.5% to 4.0% was required to increase shear values of cooked products. Adhesion at the film‐meat interface did not increase until the NaCl concentration was >3.0%. In studying type of phosphate or NaCl concentration effects, higher adhesion occurred for packaging films having a nylon sealant layer as compared to films with sealants of Surlyn or a nylon‐Surlyn blend.
In Vitro Estimation of Iron Availability from Meals and Beef: Effect of Processing and Fortification
Authors: LOMBARDI‐BOCCIA GINEVRA , CARNOVALE EMILIA
Published: August 2006

The effect of meal composition, cooking, drying and fortification on in vitro iron availability from meals (50% meat, 50% vegetables) and meat was studied. Fortification was carried out with electrolytic iron powder. Unfortified samples were also studied. In fortified meals, iron availability (8.5% in raw sample) was not affected by cooking and drying processes. However, cooking and drying reduced chemical availability of iron in unfortified meals. Similar results were obtained with meat: upon cooking its iron availability showed a reduction of 26% and 4%, in unfortified and fortified samples, respectively. Therefore, fortification reduced losses due to processing. Presence of vegetables (50%) reduced dialyzable iron by 35%.
Functional Characteristics of Wiener‐Type Products Substituted with Native and Acid‐Hydrolyzed Oat Protein Isolates
Authors: MA C.‐Y , CAMPBELL C. , KHANZADA G. , MODLER H.W.
Published: August 2006

Wiener‐type products containing 5, 10 and 20% oat protein isolates (OPI), acid‐hydrolyzed OPI or legume proteins were prepared and compared to an all‐meat control. Cook yields progressively decreased with increases in the level of substitution, but there was no significant difference (p < 0.05) among samples containing the same amount of vegetable proteins. Wiener‐type products containing acid‐hydrolyzed OPI had significantly higher firmness and cohesiveness than those substituted with other vegetable proteins.
Effect of Low‐Dose Irradiation and Post‐Irradiation Cooking and Storage on the Thiamin Content of Fresh Pork
Authors: JENKINS R.K. , THAYER D.W. , HANSEN T.J.
Published: August 2006

Low‐dose gamma irradiation of vacuum‐packaged, ground fresh pork resulted in a dose‐dependent, first‐order rate of thiamin destruction (R2= 0.99). Thiamin losses for raw pork irradiated at 0.57, 1.91, 3.76, 5.52 and 7.25 kGy were 7.7, 23.5, 38.1, 49.8 and 57.6%, respectively, of the nonirradiated sample. Post‐irradiation cooking resulted in additional thiamin losses of 11.3, 11.5, 13.0, 13.6, 13.5 and 15.0% for respective treatment samples irradiated at doses of 0, 0.57, 1.91, 3.76, 5.52 and 7.25 kGy. Time of storage had little effect on the thiamin content of raw irradiated and nonirradiated pork.
Volatile Flavor Components in Crayfish Waste
Authors: TANCHOTIKUL URAIWAN , HSIEH THOMAS C.‐Y.
Published: August 2006

Volatile components of crayfish processing waste were analyzed by dynamic headspace/capillary gas chromatography/mass spectrometry and chromatography‐coupled aroma perception analysis with simultaneous photoionization detection. One hundred seventeen compounds were identified. The majority of the flavor compounds previously identified in freshly boiled crayfish tail meat and hepatopancreas also were detected in crayfish waste. Many areas in the headspace profile contained good nutty, green woody, sweet fruity and very desirable salty meaty aromas, indicating the presence of important crayfish flavor components in the sample.
Comparison of Ferric Glycinate to Ferrous Sulfate in Model Infant Formulas: Kinetics of Vitamin Losses
Authors: GALDI M. , CARBONE N. , VALENCIA M.E.
Published: August 2006

Ferric glycinate prooxidant properties were compared with those of ferrous sulfate in a powdered casein‐based infant formula. About 60 ppm of either iron source were added separately to the experimental formula. Fortified formulas were then stored at 20°C, 37°C or 45°C for 12, 9 or 7 months, respectively. The samples were assayed periodically during storage for vitamins A, E, B1, B2 and C evaluation. Ferric glycinate fortification yielded a 30‐50% deterioration of the rate constant values of those obtained for ferrous sulfate addition. A 10‐30% increase in activation energy values was also observed when ferric glycinate replaced ferrous sulfate as iron source. Results demonstrated lower prooxidant properties of iron when added to this infant formula as ferric glycinate than when ferrous sulfate was present.
New Imidazoles Formed in Nonenzymatic Browning Reactions
Authors: VELÍŠEK J. , DAVÍDEK T. , DAVÍEK J. , TRŠKA P. , KVASNIČKA F. , VELCOVÁ K.
Published: August 2006

1,3‐Bis(carboxymethyl)imidazole was identified in a model reaction mixture derived from glycine, glyoxal, and formaldehyde. The same compound was also found in the reaction of glycine with glyoxal. The structure of this compound was elucidated from the measured molecular, mass and 1H‐NMR and 13C‐NMR spectral data and confirmed by X‐ray crystallographic measurements. Similarly, a 2‐methyl‐, 4‐methyl‐, and 2,4‐dimethyl‐1,3‐bis(carboxymethyl)‐imidazole were formed in reactions of glycine with glyoxal or methylglyoxal and formaldehyde or acetaldehyde. These 1,3‐symmetrically substituted imidazoles represent quite a new group of N‐containing heterocyclic compounds originating in model systems containing amino acids and α‐dicarbonyl compounds and probably also in natural systems.
Effects of Polyphosphates on Cell Numbers, Enterotoxin A, and Extracellular Protein in Staphylococcus aureus 196E
Authors: SHELEF LEORA A. , WANG ZHI‐LING
Published: August 2006

Effects of sodium salts of pyro‐ (SAPP), tripoly‐ (STPP), and hexametaphosphate (SHMP) on cell numbers, enterotoxin A (SEA) and extracellular protein production (ECP) of Staphylococcus aureus strain 196A were studied in 4% N‐Z amine broth plus 1% yeast extract after 24 hr at 30°C. At pH 7.0, concentrations lower than 56 mM (1.2%) SAPP, 27 mM (1%) STPP or 3 mM (0.4%) SHMP had no antibacterial effects and a bacteriostatic effect showed at slightly higher concentrations. SAPP was the least effective inhibitor at neutral pH, but displayed enhanced inhibitory effects at pH 5.5. Reduction in SEA and ECP paralleled cell growth suppression; their concentrations were 1400 ng/mL and 1.5 mg/mL, respectively, in phosphate free broth (9 × 109 CFU/mL), and nondetectable when cell numbers were ≤106 per mL.
Effect of Ionizing Radiation on Cholesterol in Aqueous Dispersion
Authors: LAKRITZ L. , MAERKER G.
Published: August 2006

Aqueous sodium stearate dispersions of cholesterol were irradiated at 0‐2°C with absorbed doses ranging from 2.5 to 50 kGy. The resulting mixture of cholesterol derivatives was isolated and examined for 7‐ketocholesterol and cholesterol 5α,6α‐epoxide and 5β,6β‐epoxide content. Concentrations of all three compounds increased with dose, while the ratio of 7‐ketocholesterol to total epoxides decreased with increasing dose. The ratio of 7‐ketocholesterol to the epoxides was approximately 1 or below at all dose levels while the same ratio in autoxidations of cholesterol in dispersions was normally 6 or greater. The change in the keto/epoxide ratio may be a means for determining whether meat or other foods containing cholesterol have been subjected to ionizing radiation.
Properties of Soybean‐Corn Mixtures Processed by Low‐Cost Extrusion
Authors: GUZMAN GABRIEL J. , MURPHY PATRICIA A. , JOHNSON LAWRENCE A.
Published: August 2006

Ground soybeans and corn at ratios 60:40, 70:30, 80:20, and 100:0 soybean :corn were extruded with an Insta Pro 600 extruder. Initial moisture content was adjusted to 10%. Extruder exit temperatures were 127, 138, 149, and 160°C. Soybean trypsin inhibitor activity was destroyed 48.9 to 98.8% as exit temperature increased. Extrusion temperature had no major effect on the tocopherol isomers. Lipoxygenase was completely inactivated by extrusion. In vitro protein digestibilities of samples extruded at 127°C were significantly lower than samples extruded at higher temperatures. Residual lipase activity ranged from 2.7 to 63.7 micromoles H+.min_I.g−1.
Effect of Germination on Oligosaccharides and Nonstarch Polysaccharides in Navy and Pinto Beans
Authors: CHANG K.C. , CHANG D.C. , PHATAK L.
Published: August 2006

Effect of germination on raffinose‐oligosaccharides, and nonstarch polysaccharides in C‐20 navy and Pindak pinto beans was investigated using solvent fractionation and chromatographic methods. Approximately 70‐80% of total raffinose and stachyose was removed by germination for 6 days. Ungerminated navy and pinto beans contained 21.75% and 18.84% total nonstarch polysaccharides, respectively. Germination did not significantly change the yields of soluble and insoluble nonstarch polysaccharides. Arabinose in the soluble nonstarch polysaccharides was significantly increased by germination. Germination increased the viscosity of soluble nonstarch polysaccharides. However, the viscosity increase of the soluble nonstarch polysaccharides from germinated pinto beans was significantly greater than that from germinated navy beans.
Determination of Fluoride in Cocoa Powder by Ion‐Selective Electrode
Authors: PESSELMAN ROBERT L. , LOKEN ROBERT G. , HOFFMAN MARK J. , FEIT MELROY J.
Published: August 2006

A method to determine free fluoride concentration in soluble cocoa powder by a fluoride‐selective electrode was developed and validated. Calibration was linear over the 0.51 to 3.03 ppm range. Free fluoride ion concentration data were in the 0.52 to 1.49 ppm range, with recoveries varying from 81% to 89% using a standard addition procedure.
Temperature‐Dependency of Rigor‐Mortis of Fish Muscle: Myofibrillar Mg2+‐ATPase Activity and Ca2+ Uptake by Sarcoplasmic Reticulum
Authors: WATABE SHUGO , USHIO HIDEKI , IWAMOTO MUNEAKI , YAMANAKA HIDEAKI , HASHIMOTO KANEHISA
Published: August 2006

Myofibrillar Mg2+‐ATPase activity of plaice and red sea bream increased with increase in reaction temperature and Ca2+ concentration. However, temperature decrease tended to lower Ca2+ sensitivity of Mg2+‐ATPase activity. While it was assumed that spiked fish muscle was relaxed and the myofibrillar Ca2+ concentration was low, the progress rate of rigor‐mortis correlated well with Mg2+‐ATPase activity in the presence of a few micromolar Ca2+ at 0°C. Correspondingly, it was found that Ca2+ uptake by plaice sarcoplasmic reticulum decreased with the decrease in reaction temperature. These results strongly suggest the acceleration of fish rigor‐mortis at 0°C is due to the increase of Ca2+ concentration in myofibrils during storage at this temperature.
Spoilage Potential of Some Contaminant Bacteria Isolated from Indian Mackerel (Rastrelliger kanagurta)
Authors: ALUR M.D. , VENUGOPAL V. , NERKAR D. P.
Published: August 2006

Pseudomonas marinoglutinosa, Aeromonas hydrophila isolated from unirradiated spoiling Indian mackerel (Rastrelliger kanagurta) and Bacillus megaterium, Micrococcus colpogenes isolated from gamma‐irradiated mackerel were examined for their spoilage potential in fish homogenate and fish muscle sarcoplasmic and myofibrillar protein fractions. Pseudomonas marinoglutinosa (0° ‐2°C), Aeromonas hydrophila (0° ‐ 2°C) and Bacillus megaterium (26°C) proliferated in the fish homogenate and sacroplasmic protein fraction which was associated with losses in sensory attributes and increase in non‐protein‐nitrogen (NPN) compounds, total volatile acids (TVA) and total volatile basic nitrogen (TVBN) compounds. On the other hand, the organisms exhibited diminished growth in MF fraction which was also accompanied by less changes in sensory and chemical quality parameters. Growth of M. colpogenes was not accompanied by putrefaction of the fish media as assessed by sensory and chemical criteria, suggesting contribution of varying spoilage potentials of the bacterial isolates in the overall spoilage of the fish.
Protection of Menhaden Mince Lipids from Rancidity during Frozen Storage
Authors: HWANG KEUM T. , REGENSTEIN JOE M.
Published: August 2006

Several antioxidants as well as vacuum packaging and changes in frozen storage temperatures (‐7°C and ‐20°C) were tested for their effect on the peroxide values and free fatty acids (FFA) of frozen minces from Gulf menhaden, Brevoortia patronus and Atlantic men‐haden, Brevoortia tyrannus. Vacuum packaging was the most effective in retarding oxidative rancidity. Storage at ‐20°C also reduced the oxidation versus ‐7°C. Ascorbic acid and crythorbic acid had the best antioxidant activity of the additives tested. Tocopherols, rosemary extracts, and tertiary butylhydroquinone (TBHQ) had limited antioxidant activity. Storage at ‐20°C inhibited hydrolytic rancidity. Neither vaccum packaging nor any of the additives prevented FFA development at ‐7°C.
Factors Relating to Oxidative Stability of Cooked Broiler Breast Patties Treated with Sodium Tripolyphosphate
Authors: ANG C.Y.W. , YOUNG L.L.
Published: August 2006

Broiler breast meat patties were prepared with 0, 0.2, and 0.5% sodium tripolyphosphate (STPP) at 3 pH values and 3 ionic strengths (IOS). The concentrations of STPP and IOS were important factors in retardation of oxidation during cooking and storage after cooking as evaluated by the thiobarbituric acid‐reactive substances (TBA‐RS) test. The effect of STPP at 0.5% was enhanced (P< 0.06) by raising its pH to 7.5 or 9. Increasing IOS by 0.6 raised TBA‐RS values in raw meat and during cooking, but it had a reverse effect on cooked‐stored patties, which was probably due to the lower nonheme iron content of cooked patties as the IOS increased.
Effect of Tempeh on Properties of Hams
Authors: KUO J. C. , WANG S. Y. , PENG A. C. , OCKERMAN H. W.
Published: August 2006

Hams made with meat plus tempeh (2% and 3.5%) had lower (P < 0.05) moisture and cooking yield; TBA values were slightly lower than the control after 30 days. Cooking yield of hams decreased with the increased amount of tempeh. Meat plus tempeh (2% and 3.5%) and (P < 0.05) lower Hunter L values and higher Hunter a values than the control. The control had higher shear force and binding strength values than those made with meat plus tempeh. Hams made with meat plus 2% tempeh and meat plus 3.5% tempeh were not significantly different from each other in overall acceptability scores but neither of these treatments was as acceptable as the control.
Physicochemical Parameters of Protein Additives and Their Emulsifying Properties
Authors: TORO‐VAZQUEZ JORGE F. , REGENSTEIN JOE M.
Published: August 2006

The relationships between protein solubility, surface hydrophobicity (Ho), free sulfhydryl (SHF) and disulfide bond (SSB) content and time of emulsification that determine the emulsion activity index (EAI) and emulsion stability (ES) of five protein additives were investigated at two different ionic strengths (Z = 0.054 and Z = 0.46, pH 6.5). The variables that described EAI at Z = 0.054 were associated with protein disperability and Ho, while protein rigidity factors explained most of the EAI variability at Z = 0.46. The ES models showed similar variable relationships as the EAI models at the same Z. The differences between models at different Z indicated that the relationships between the variables were affected by the ionic strength.
Comparison of Transparent Gels with Turbid Gels Prepared from Egg White: Creep Analysis of Gels
Authors: KITABATAKE NAOFUMI , SHIMIZU ATSUSHI , DOI ETSUSHIRO
Published: August 2006

Egg white from which the precipitate occurring during dialysis against water had been removed gave a transparent gel on heating at lower salt concentrations and pH 3.54. The addition of NaCl or a shift of pH from 3.54 to 4.50 brought about the turbid gels. Creep analyses of these transparent and turbid gels were done using a four‐element mechanical model. The instantaneous elastic modulus, E0, Newtonian modulus, ηn and retarded viscoelastic moduli, E1 and η1 increased with NaCl up to 125 mM and then decreased with increase in NaCl concentration at pH 3.54. At 125 mM NaCl and pH 3.54, a translucent gel was obtained. E0 and η1 decreased with the temperature of the gel, while E1 and η1did not change depending of temperature.
Comparison of Ferric Glycinate to Ferrous Sulfate in Model Infant Formulas: Kinetics of TBA, Lysine and Methionine Changes
Authors: GALDI M. , CARBONE N. , VALENCIA M.E.
Published: August 2006

Ferric glycinate prooxidant properties were compared with those of ferrous sulfate in a powdered casein‐based infant formula. About 60 ppm of either source were added to experimental formulas, and supplemented formulas stored at 20, 37 or 45°C for 7–12 months. The samples were assayed periodically during storage for methionine and available lysine losses, and malonaldehyde formation. Deterioration rate constants for the ferric glycinate‐fortified formula dropped to 60–75% of those for the ferrous sulfate‐fortified formula. Activation energy values obtained for the glycinate iron source were 15–20% higher than those for ferrous sulfate. Thus, iron had lower prooxidative properties when added to this infant formula as ferric glycinate than when present as ferrous sulfate:
Fermentative Activity of Baker's Yeast Cultivated on Cheese Whey Permeate
Authors: CHAMPAGNE C .P. , GOULET J. , LACHANCE R. A.
Published: August 2006

Fermentative characteristics of Baker's yeast (Saccharomyces cerevisiae) produced on two cheese whey ultrafiltrate media (one in which lactose was hydrolyzed and one pre‐fermented by Streptococcus thermophilus) were compared to those of yeast produced on molasses. Fermentative activity of yeast grown on molasses was superior to that of cells produced in whey. Addition of sucrose to pre‐fermented whey ultrafiltrate (FWU) in the final stage of the fermentation increased fermentative activity. Fermentative activity of three strains grown on FWU varied considerably, certain strains being better adapted to the whey media. Breads produced with yeast grown on FWU were identical to those obtained with cells grown on molasses.
Calorimetric Examination of Cut Fresh Pineapple Metabolism
Authors: IVERSEN ERIC , WILHELMSEN ERIC , CRIDDLE R. S.
Published: August 2006

Isothermal microcalorimetric analysis of cut fresh pineapple was used to examine metabolic events occurring in the fruit under different storage conditions. The results define conditions most suited for cut pineapple storage. The baseline heat production for pineapple tissue is quite low (0.2 μW per mg wet weight). During storage, heat producing metabolic reactions develop which cause spoilage of the fruit. The time course of heat production during storage is affected by changes in atmosphere and by chemical treatments. Effects of inhibitor and antibiotic additions indicate that most of the heat production associated with spoilage is related to the growth of microbial flora.
Effect of Methyl Ester Content on Heat Degradation of Chelator‐Soluble Carrot Pectin
Authors: SAJJAANANTAKUL T. , VAN BUREN J. P. , DOWNING D. L.
Published: August 2006

Chelator‐soluble pectin was isolated from carrot under mild conditions and used as a model compound for an investigation of the heat degradation mechanism of pectin in an aqueous environment. Methyl ester content was modified with minimal changes in the polymer size. At pH 6.1 the heated pectin preparation degraded primarily through β‐eliminative cleavage of the chain. The higher the methyl ester content the greater the degradation. Evidences also indicated a‐small amount of hydrolytic cleavage of glycosidic bonds which was not affected by the presence of the methyl ester content. De‐esterification of methyl ester groups proceeded at a faster rate than the eliminative cleavage of the chain; however, under the test conditions, it did not terminate the β‐elimination.
Functional Properties of Whey‐Pea Protein Composite Blends in a Model System
Authors: JACKMAN ROBERT L. , YADA RICKEY Y.
Published: August 2006

Protein from pea (Pisum sativum) and acid whey were combined in various proportions and several functional properties of resulting composites determined at pH 4 to 8. Solubility, heat stability, emulsion properties and foaming capacity were significantly (p < 0.05) reduced with decreasing pH (especially at pH 5) and increasing pea protein. Maximum thermocoagulation of composites increased threefold in magnitude and shifted from pH 4–5 to 5–6 as pea protein increased. A significant (p < 0.001) correlation between protein solubility and other functional properties was shown to be a direct consequence of the proportion of pea protein combined with whey protein, pH and their interaction.
Puffing of Rice Cakes as Influenced by Tempering and Heating Conditions
Authors: HSIEH F. , HUFF H. E. , PENG I. C. , MAREK S. W.
Published: August 2006

Puffed rice cakes were produced from long grain brown rice by a pressure‐drop puffing method. Effects of raw rice tempering conditions (time and moisture level) and heating conditions (temperature and time) immediately before puffing on rice cake volume were investigated. In general, a lower moisture level (14% vs 16–20%) in raw rice and longer tempering time (5 hr vs 1–3 hr) resulted in higher specific volumes in rice cakes. Higher heating temperature (230°C vs 200–220°C) and 8 sec heating produced rice cakes with higher specific volumes. Darker cakes were obtained with the high temperature and long time combinations.
Relative Emulsifying Activity of Bovine Serum Albumin and Casein as Assessed by Three Different Methods
Authors: HAQUE ZAHURUL , KINSELLA JOHN E.
Published: August 2006

The relative emulsifying activities of bovine serum albumin (BSA) and casein as determined by computerized optical microscopy, electron microscopy and spectroturbidimetry at a protein concentration of 0.135 mM (pH 7) and an oil:water (o:w) ratio of 4:6, was compared. Repeated homogenization led to a more homogeneous distribution of dispersed phase globules. BSA stabilized globules became smaller, e.g. the mean globule diameter determined by the different methods decreased from 3.1 μ at an energy input of 7.6 × 107 J m−3 to 2.2μ, at 182 × 107 J m−3. Casein stabilized globules became larger with energy input, e.g. mean dvs increased from 5.0μ at 7.6 × 107 J m−3 to 5.8μ. at 182 × 107 J m−3 indicating structure dependent differences in the emulsifying activity of protein.
Deamidation and Functional Properties of Food Proteins by the Treatment with Immobilized Chymotrypsin at Alkaline pH
Authors: KATO AKIO , LEE YOSHINORI , KOBAYASHI KUNIHIKO
Published: August 2006

Ovalbumin, lysozyme, 7S globulin, 11S globulin, and gluten were treated with immobilized chymotrypsin on controlled‐pore glass at pH 10 at 20°C to improve their functional properties. Optimum pH of deamidation of ovalbumin by immobilized chymotrypsin was 10, where proteolysis was very limited. Deamidation percentages of ovalbumin, lysozyme, 7S globulin, 11S globulin, and gluten were 10.0, 8.4, 6.0, 5.0, and 8.0, respectively. SDS polyacrylamide gel electrophoretic patterns of ovalbumin and lysozyme showed no difference between untreated and treated proteins, while those of soy proteins and gluten showd that larger molecular weight fractions were dissociated into smaller molecular size fractions. Solubility of gluten was greatly improved at all pHs, 2‐12. Both emulsifying and foaming properties of proteins were improved by treatment with immobilized chymotrypsin.
Effect of Whey Pretreatment on Composition and Functional Properties of Whey Protein Concentrate
Authors: KIM S‐H. , MORR C.V. , SEO A. , SURAK J.G.
Published: August 2006

The effect of pretreatment upon the composition and physicochemical and functional properties of whey, ultrafiltration (UF) retentate and freeze‐dried and spray‐dried whey protein concentrates (WPC) was investigated. Pretreatment was by cooling cheese whey to 0‐5°C, adding calcium chloride, adjusting to pH 7.3, warming to 50°C, and removing the insoluble precipitate that formed by centrifugation or decantation. UF permeation flux rate of pretreated whey was about double that for control whey. Pretreated whey was essentially turbidity free, contained 85% less milkfat, 37% more calcium and 40% less phosphorus than whey. Pretreated whey WPC proteins were slightly more soluble at pH 3, but less functional for emulsification than whey WPC proteins. Neither whey WPC proteins nor pretreated whey WPC proteins was functional for foaming at 6% protein concentration.
Rheological Properties of Pasteurized Liquid Whole Egg During Frozen Storage
Authors: HERALD T. J. , OSORIO F. A. , SMITH D. M.
Published: August 2006

Effects of pasteurization and frozen storage on the rheological behavior of liquid whole egg (LWE) were studied using a cone and plate viscometer. Homogenized LWE control and LWE heated at 60°C, 64°C or 68°C for 3.5 min were evaluated during 80 days storage at −24°C. Thixotropic behavior was observed in all frozen samples. Apparent viscosity increased with pasteurization and frozen storage. Unpasteurized LWE exhibited Newtonian behavior throughout storage. Pasteurized LWE flow properties changed from Newtonian to Bingham Plastic during storage. Identification of rheological parameters will help understand the molecular changes that occur during the processing and storage of LWE and help processors monitor LWE quality.
Binding of Vanillin by Fababean Proteins
Authors: NG P.K.W. , HOEHN E. , BUSHUK W.
Published: August 2006

Binding of vanillin by fababean protein micellar mass (PMM) in water suspensions was investigated. Free vanillin was determined by HPLC and data were evaluated by the Klotz equation. Increasing vanillin and PMM concentrations increased the percentage of total vanillin bound to protein. Binding capacities of heat‐treated (denatured) PMM were higher than that of untreated (native) PMM. Binding forces between vanillin and PMM were weak, and the number of binding sites increased when PMM was denatured.
Location of the Slowest Heating Zone for Natural‐Convection‐Heating Fluids in Metal Containers
Authors: ZECHMAN L G. , PFLUG I. J.
Published: August 2006

Studies were conducted to locate the slowest heating zone (SHZ) along the vertical axis of vertically positioned containers for 16 liquids of different physical properties in 211 × 400 metal containers and for water in 13 sizes of metal container, and to assess significance of the findings for the design of thermal processes. For conditions tested, SHZ was found near the container bottom. The SHZ for natural‐convection‐heating products is usually located no higher than 25% of the container height above the container bottom. The SHZ's location is most critical in thermal process design for liquids of high initial viscosity in small containers where there is a large difference in temperature between heating medium and SHZ at the end of heating.
Physical and Functional Properties of 10% Salted Egg Yolk in Mayonnaise
Authors: YANG SHENG‐SHIN , COTTERILL OWEN J.
Published: August 2006

Stability of mayonnaise prepared from 10% salted egg yolk was decreased by freezing, spray‐drying or freeze‐drying of the yolk. Storage of salted yolk for 90 days further decreased stability of mayonnaise made from freeze‐dried yolk but not that made from frozen spraydried yolk. Stiffness of mayonnaise was increased by pasteurization but stability was increased only at the lesser of two heat treatments. Size of fat globules in the mayonnaise was inversely related to mayonnaise stability.
Corn Germ Protein Flour as an Extender in Broiled Beef Patties
Authors: BROWN L.M. , ZAYAS J.F.
Published: August 2006

Beef patties were extended at levels of 10, 20, and 30% of the uncooked weight with hydrated defatted corn germ protein flour (CGPF). Extended patties had lower cooking losses and higher cooked yields than control patties. Adding CGPF did not affect moisture or fat contents in broiled patties, but lowered protein content. The amino acid composition of experimental patties was comparable to that of the control. The water‐holding capacity and pH of raw patties increased with increasing levels of added CGPF. Incorporation of CGPF affected sensory characteristics of the product; meaty aroma and flavor of all‐meat patties was significantly higher than experimental samples and decreased with an increase in added CGPF. CGPF has potential use as an extender in coarsely ground meats.
Dialyzable Calcium from Milk Processed with Soluble Fiber‐Containing Gums, Thickeners, and Cocoa
Authors: KELLY BRENDA J. , POTTER NORMAN N.
Published: August 2006

Dialyzable calcium form 10% nonfat dry milk (NFDM) processed with gums, thickeners, and cocoa was determined following in vitro peptic‐pancreatic digestion. Acidification to pH 4.2, heat pasteurization, or boiling for 30 min did not affect the % dialyzable calcium from 10% NFDM alone or in the presence of any of the additives tested. At a level of 1%, carrageenan, gum arabic, gum karaya, and low‐methoxyl pectin significantly decreased (p < 0.05) and agar increased (p < 0.01) % dialyzable calcium. Other gums and thickeners were without effect and viscosity of the food system did not correlate with % dialyzable calcium. Five percent Dutch or natural process cocoa caused a one‐third reduction in dialyzable calcium and 1% Dutch cocoa also produced a significant decrease.
Harvest Date and CA Storage Management Effects on Quality of Processed Apple Slices
Authors: McLELLAN M.R. , BLANPIED G.D. , MASSEY L.M.
Published: August 2006

The effect of harvest date and various controlled atmosphere [CA] delays was studied on an apple slice production line. Harvest date interacted with delay in placing apples under CA conditions, causing dramatic softening of the blanched apple slices. The effect on the blanched slices was much greater than that on raw slices. Numerous process parameters including waste amounts and yields were notably affected by various treatment combinations.
Freezing of Banana Slices. Influence of Maturity Level and Thermal Treatment Prior to Freezing
Authors: CANO PILAR , MARIN M. ANTONIA , FUSTER CARMEN
Published: August 2006

Freezing preservation of banana (Musa cavendishii, var. enana) was investigated. Microwave treatment of banana slices at 650 watts for 2 min or immersion of whole peeled fruits in boiling water for 11 min followed by freezing at ‐24°C inhibited color deterioration in the frozen product. Treatments showed different effectiveness depending on the enzymatic system studied [polyphenoloxidase (PPO) or peroxidase (POD)] and banana maturity level at the processing date. Blanching in boiling water yielded a good frozen product in which no darkening was observed. The proper stage of ripeness for processing of this banana cultivar was characterized by a firmness of 1.24 kg, a pulp/skin ratio of 1.30 and a green (70%)‐yellow (30%) peel color.
Instrumental and Sensory Evaluation of Textural Properties of Extrudates from Blends of High Starch/High Protein Fractions of Dry Beans
Authors: SKIERKOWSKI KRZYSCTOF , GUJSKA ELZBIETA , KHAN KHALIL
Published: August 2006

A Wenger X5 single‐screw extruder was used to produce bean extrudates from formulations modified by addition of high protein bean fraction or hull. The effect of process temperature was investigated. The higher the process temperature, the lower was the sample stress and the higher the sensory score for crispness. Product processed below 121°C was unacceptable. Crispness was good for samples containing 13–16% protein or 17–21% fiber; outside these ranges the extrudates were too hard. Shear stress increased uniformly with increasing protein or fiber content. A satisfactory correlation was observed between sensory and instrumental test results for texture: the higher the shearing stress, the lower was the sensory score for crispness.
Purification of Milk Catalase by Immunoaffinity Chromatography
Authors: ITO O. , KAMATA S. , KAKI‐ICHI N. , SUZUKI Y. , HAYASHI M. , UCHIDA K.
Published: August 2006

Antiserum against commercially available bovine liver catalase was prepared in rabbits. Anti‐catalase antibody in serum was prepared following 30% ammonium sulfate treatment and Sephacryl S‐300 column chromatography. The anti‐catalase antibody was coupled to cyanogen bromide‐activated Sepharose 4B, and using this immunoadsorbent crude milk catalase was purified. About 7.0 mg pure catalase was produced from 10 kg milk. Activity of the purified products was about 2.58 × 104 times as pure as cows' milk. The purified catalase was electrophoretically homogeneous, appearing as a single band.
Sogurt, a Yogurt‐like Soybean Product: Development and Properties
Authors: CHENG Y.J. , THOMPSON L.D. , BRITTIN H.C.
Published: August 2006

Two sogurt products were prepared by fermenting a formulation containing soymilk, 0.15% calcium acetate, 0.5% gelatin, and lactose (0 or 2%) with Lactobacillus casei and Streptococcus thermophilus. Commercial plain yogurt was used as a control. Sogurts were evaluated for aroma, taste, texture, titratable acidity, pH, and color. Sogurts had beany and raisin aromas, more bitter and astringent tastes than yogurt, and slightly sandy mouth‐ feel. Sogurts and yogurt did not differ (P < 0.05) in intensity of butter aroma. Sogurt with lactose did not differ (P < 0.05) from yogurt in acidity. Sogurts were yellower and firmer than yogurt.
Study of the White Film Developed on the Cut Surface of Vacuum‐packed Dry‐cured Ham Slices
Authors: TOLDRÁ FIDEL , FLORES JOSÉ , VOYLE CHARLES A.
Published: August 2006

Scanning electron microscopy of the white film developed on the cut surface of some vacuum‐packed dry‐cured ham slices showed a fibrous structure composed of protein materials. Gradient SDS‐PAGE revealed the main components in the film were proteins with molecular weight in the range 26000–87000, but especially 37000, 41000, 56000, and 65000. Free amino acids were also in the film in low proportions (250 μg total free amino acids per mg of protein). The main amino acids were proline methionine, isoleucine, leucine, phenylalanine, histidine and tyrosine. 11.7% of the total free amino acids was tyrosine, thus indicating its minor role in formation of white film.
Cholesterol Content of Restructured Pork/Soy Hull Mixture
Authors: IBRAHIM N. , UNKLESBAY N. , KAPILA S. , PURI R.K.
Published: August 2006

The effect of convective heat processing was studied on cholesterol and its oxides in a restructured pork/soy hull model system. Products were analyzed from 30 different time‐temperature conditions of processing. Following lipid extraction, GC‐MS was used for analysis of cholesterol and its oxides. No cholesterol oxides were found at 2 ppm in the product with any of the 30 time‐temperature profiles, ranging from 19 ‐89.6 min of heat processing, and 9–97°C final product temperatures. Cholesterol in heat‐processed samples ranged from 45.43–66.47 mg/l00g. Positive correlations were found between final temperatures and fat and cholesterol content.
Effect of an Edible Collagen Film Overwrap on Exudation and Lipid Oxidation in Beef Round Steak
Authors: FAROUK M.M. , PRICE J.F. , SALIH A.M.
Published: August 2006

Beef round steak when wrapped with an edible collagen film (Coffi®) exhibited much less fluid exudate (P<0.05) than unwrapped controls. This was true in refrigerated and frozen/thawed samples with standard retail (permeable film overwrap) or vacuum (pouch) packaging. Vacuum packaging produced more exudate and a less bright red color than retail packaging. Coffi® had no significant effect on color or lipid oxidation by TBA. Objective measures of color and exudate quantity highly correlated with panel scores for the same parameters (r values of 0.91 and 0.95). TBA values were lower (P<0.05) in refrigerated vacuum‐packaged than in retail‐wrapped samples. The impact of vacuum on TBA was less apparent in frozen samples.
Free Amino Acids in Cheddar Cheese: Comparison of Quantitation Methods
Authors: LEMIEUX L. , PUCHADES R. , SIMARD R.E.
Published: August 2006

Two reported methods were compared with a more rapid and accurate flow injection analysis (FIA) technique. A trinitrobenzenesulfonic acid (TNBS) method provided absolute values, was tedious, and the reagent was light‐sensitive and required heating. An o‐phthaldialdehyde (OPA) method was faster and less variable than the TNBS, but reaction time had to be carefully controlled. The results with the OPA correlated well with the TNBS but were overestimated due to reading small peptides and ammonium ions. The FIA method was simple and reliable, yielded values which correlated closely with amino acids and gave information about degree of proteolysis.
Determination of Free Amino Acids in Cheese by Flow Injection Analysis with an Enzymic Reactor and Chemiluminescence Detector
Authors: PUCHADES R. , LEMIEUX L. , SIMARD R.E.
Published: August 2006

The substrate is degraded enzymatically by L‐amino acid oxidase immobilized on controlled porosity glass. The hydrogen peroxide generated by the reaction is determined by chemiluminescence with an alkaline reagent containing luminol and hexacyanoferrate (III). The log‐log calibration graphs for L‐leucine were rectilinear from 0.025 mM to 1.0 mM (R = 0.9998). The coefficients of variation (rds) for n = 10 were 1.4% and 0.3% for 0.1 mM and 0.8 mM of L‐leucine, respectively. The sample throughout was 40 h‐1. The concentration of free amino acids in cheese samples was 14 to 50 mg L‐leu/g product. The enzyme reactor showed good stability over 4‐months.
Recovery of Proteins from Raw Sweet Whey Using a Solid State Sulfitolysis
Authors: GONZALEZ JUAN M. , DAMODARAN SRINIVASAN
Published: August 2006

A simple, efficient method to recover functional proteins from cheese whey was developed. It involves partial sulfitolysis of disulfide bonds in whey proteins using sodium sulfite and solid state copper carbonate catalyst. About 25 to 40% of the initial disulfide bonds were modified within 15 to 30 min at pH 7.0. When treated whey was adjusted to acidic pH, about 70 to 80% of the whey proteins precipitated below pH 5.0. The protein precipitate contained some copper as protein‐copper complex. However, extraction of the precipitate with EDTA at pH 4.5 completely removed the copper. The uncomplexed protein showed a U‐shaped pH‐solubility profile with 100% solubility below pH 3.0 and above 6.0. About 90% of the proteins precipitated in the pH range 4.0 to 5.0. The method could be used on an industrial scale to recover highly functional and nutritional whey protein for use in a variety of products.
Use of Bicarbonates for Microbial Control and Improved Water‐Binding Capacity in Cod Fillets
Authors: CURRAN DONNA M. , TEPPER BEVERLY J. , MONTVILLE THOMAS J.
Published: August 2006

Dipping cod fillets in ammonium or sodium bicarbonate solutions markedly reduced microbial growth compared to untreated samples after 8 days at 4°C. Total plate counts, proteolytic bacteria and H2S‐producing bacteria were inhibited. Mixing ammonium‐ and sodium bicarbonates at selected ratios maintained the preservative effect while reducing the ammonia odor. The treated fish had improved texture and moisture retention by both objective and subjective testing but had significantly lower aroma and overall acceptability scores from sensory evaluation.
Role of Noncovalent Forces in Micellization Using Legumin from Vicia faba as a Study System
Authors: ISMOND M.A.H. , GEORGIOU C. , ARNTFIELD S.D. , MURRAY E.D.
Published: August 2006

The seed storage protein, legumin, from Vicia faba interacted to form micelles and elaborate protein networks under varying conditions. Several molecular parameters correlated with observed micelle interaction parameters; these included thermal properties as indicators of protein stability and surface hydrophobicity as an assessment for potential hydrophobic interactions. The optimal pH for micelle formation ranged from 5.5 to 6.5, values at which electrostatic repulsions were minimal and surface hydrophobicites were adequate to allow hydrophobic interactions. The micelle response was affected by anions both in terms of concentration and type of anion. Finally, gradual denaturation of legumin with increasing urea concentrations had a negative impact on the micelle response.
Evaluation of Emulsion Stability by Centrifugation with Conductivity Measurements
Authors: LATREILLE B. , PAQUIN P.
Published: August 2006

An industry problem when evaluating stability of emulsions is lack of a method reproducing, in a short time, aging of the emulsion. A method that combines centrifugation and conductivity measurements could be used for this purpose. Centrifugation accelerates destabilization of the product and thus simulates aging. Conductivity measurement of the aqueous phase, a function of the oil concentration, evaluates destabilization. Our method was compared with a creaming‐measurement method based on fat content. The increase in conductivity was representative of the creaming rate, with correlation higher than 0.93. The combined method, applied to different oil‐in‐water (O/W) emulsions, enables following stability during aging and assures the need of industry for a fast, easy method to evaluate emulsion stability.
Radiolytic Degradation of Sorbic Acid in Isolated Systems
Authors: THAKUR B.R. , TREHAN I.R. , ARYA S.S.
Published: August 2006

Effect of Co60γ‐irradiation on stability of sorbic acid (SA) in solutions, dough and chapaties has been investigated. SA was highly susceptible to radiolytic degradation in aqueous systems. Rate of degradation decreased with rise in pH. Sugars, hydrocolloids except pectin, citric acid, lactic acid, malic acid, arginine and threonine, catalysed degradation while oxalic acid, maleic acid, Cu2+, nitrite, nitrate and phthalate had protective effects. SA was more stable in alcohols and vegetable oils than in aqueous solutions. In wheat flour radiolytic degradation of SA was less at lower moisture. Relatively SA was more stable in chapaties than in dough. Gelatinization and addition of oil in dough reduced degradation of SA.
Mutagenicity and Identification of the Reaction Products of Aqueous Chlorine or Chlorine Dioxide with L‐Tryptophan
Authors: OWUSU‐YAW J. , TOTH J.P. , WHEELER W.B. , WEI C.I.
Published: August 2006

Nonvolatile products generated from reactions of graded molar ratios of aqueous chlorine or chlorine dioxide with L‐tryptophan (1:1, 3:1 and 7:1) were shown to be direct‐acting mutagens to Salmonella typhimurium TA100 and TA98. Increasing the ratio of disinfectant relative to amino acid led to increased mutagenic activity, with mutagenicity highest at the 7:1 molar ratio. Several fluorescent bands obtained after thin layer chromatographic fractionation of the reaction mixtures were shown to be more mutagenic than the reaction mixtures. GC/MS analysis of the compounds in a highly mutagenic fraction of the aqueous chlorine reaction products identified 1,1,3‐trichloropro‐panonc, 1,1,3,3‐tetrachloropropanone and dichloroquinoline.