bluuebunny/crossref_metadata_2025 huggingface dataset:
Polyphenoloxidase Activity, Polyphenols Concentration and Browning Intensity during Soursop (Annona muricata, L.) Maturation
Authors: LIMA DE OLIVIERA SUZANA , GUERRA NONETE BARBOSA , SUCUPIRA MACIEL MARIA INÊS , SOUZA LIVERA ALDA VERÔNICA
Published: August 2006

Values for polyphenoloxidase (PPO), total phenols and ascorbic acid, browning intensity and pH in soursops (Annona muricata, L.) decreased during maturation. Optimum pH was 7.5 (fully developed immature, mature unripe and ripe fruits) or 7.0 (fully ripe fruits). High correlation was found between PPO activity and phenolic compounds. The enzymic browning of soursops occurred during maturation. The least browning intensity was in fully ripe fruits.
Thermoluminescence Spectra of Inorganic Dust from Irradiated Herbs and Spices
Authors: CALDERÓN T. , RENDELL H.M. , BENEITEZ P. , TOWNSEND P.D. , MILLAN A. , WOOD R.
Published: August 2006

Thermoluminescence (TL) is used to determine whether certain foodstuffs have been irradiated. A high sensitivity TL spectrometer was used to analyze irradiated and unirradiated inorganic dusts from herbs and spices. Unlike earlier TL work using emissions in the UV‐green spectral range, the spectrometer monitored transient TL emissions across the spectral range from UV to infra‐red as samples were heated to 400°C. A strong high temperature red emission peak was detected in all irradiated samples. This signal was much higher than the background level, insensitive to post‐irradiation light exposure, and has potential for irradiation exposure determination.
Phospholipid Hydrolysate and Antistaling Amylase Effects on Retrogradation of Starch in Bread
Authors: KWEON M.R. , PARK C.S. , AUH J.H. , CHO B.M. , YANG N.S. , PARK K.H.
Published: August 2006

Effects of phospholipid hydrolysate and antistaling amylase on starch retrogradation in bread and wheat flour were investigated by differential scanning calorimetry (DSC). Phospholipid hydrolysate containing more than 90% lysophospholipid was obtained using phospholipase A2 and was effective in forming amylose‐lipid complexes. Both wheat flour and bread containing phospholipid hydrolysate were retrograded to a lesser degree when stored at room temperature. The retrogradation rate for bread with antistaling amylase was low. We postulated that antistaling amylase broke links in amylose and amylopectin, thereby promoting the formation of amylopectin‐lipid complexes. The combined effect of phospholipid hydrolysate and antistaling amylase was greater than their individual effects.
Rheological Studies of Water‐Soluble (1–3),(1–4)‐β‐D‐Glucans from Milling Fractions of Oat
Authors: WIKSTRÖM KATARINA , LINDAHL LENNART , ANDERSSON ROGER , WESTERLUND ERIC
Published: August 2006

We studied the rheological properties of water‐soluble, mixed‐linkage β‐glucans of high purity (88–99.5%) isolated from oats. Comparing the β‐glucan fractions at the same concentration (1.3 mg/g) the mean value of the bran fraction viscosities was larger (by 5X) than the mean viscosity of endosperm fractions. Both mean values had a relative standard deviation of ∼20%. Heat treatment of oats did not alter the viscous properties of the extracted β‐glucans. Activation energies for the bran fraction at two shear rates were Er=5.81= 42 kJ/mole and Er=581= 17 kJ/mole. The variation in G′and G′ with frequency for the β‐glucan from bran fractions could be qualitatively described by a superposition of two single Maxwell models with widely different relaxation time. These data can help predict potential processing effects on such fractions incorporated as food components.
High‐Protein Oat Flour Functionality Assessment in Bread and Sausage
Authors: LAPVETELÄINEN A. , PUOLANNE E. , SALOVAARA H.
Published: August 2006

The effectiveness of high‐protein oat flour, a by‐product of an oat starch process, was studied in bread baking and sausage processing. Its impact on sensory properties of products was assessed. High‐protein oat flour enhanced water absorption and mixing stability of the dough. Some weakening of dough was found as indicated by a decrease in extensibility and resistance. Addition of oat flour increased loaf volume, enlarged grain size and darkened crumb color. It also caused some off‐odors assessed as a decrease in “cleanness” of aroma. Sausages containing high‐protein oat flour formed an external gel‐like layer under the casing during processing, probably caused by the low pH of the flour. In sensory analyses the sausages were judged less firm and juicy than the control. The “cleanness” of odor and flavor of the sausages was distinctively diminished. Cereal products should be considered the primary products for utilization of high‐protein oat flour.
Proton Low‐Field NMR Measurements on Crackers
Authors: DESBOIS PASCAL , LE BOTLAN DENIS
Published: August 2006

We have shown that the signal obtained for crackers (3.5% water content) by low resolution NMR method using the CPMG sequence, described the relaxation of the protons of fat. For water content up to 7.1% the water signal is not seen by a CPMG sequence, the water has therefore a very short spin‐spin relaxation time (T2 < 0.5 ms). However, that water modifies the mobility of protons of fat at solid‐liquid interfaces. Protons exchangeable by deuterium affect neither the relaxation time of the short component (about 1 ms), nor its intensity. Between 7.1% and 14.8%, the water had a spin‐spin relaxation time of about 1 msec and its signal was added to the short component of the fat. Thus, low resolution NMR could be used to follow the crystallization of fat in such samples after cooking.
Flow Properties of Canola Seed Pastes
Authors: WANG FANGZHI , MEISEN AXEL
Published: August 2006

Flow properties of Canola seed pastes, prepared by crushing seeds to <0.125 mm dia. and adding Canola oil, were measured under the following conditions: shear rate 0.1 to 225 s−1, concentration 35.3 to 95.7% (g solid/g liquid), temperature 288.15 to 328.15 K. The pastes were shear thinning and their rheological behavior was described by a Herschel‐Bulkley model. For solid concentrations ≥ 40%, a turning temperature (T′) was noted. Below T, the shear stress fell with increasing temperature but above T shear stress increased with increasing temperature.
Malt Concentrates and their Mixtures with Sweetened Condensed Milk: Moisture Sorption Isotherms
Authors: SINGH T.
Published: August 2006

Moisture sorption isotherms of malt extract concentrates with and without sweetened condensed milk were determined using a gravimetric procedure. Isotherms were type I, typical of high sugar foods. Desorption curves above the absorption showed hysteresis. Monolayer moisture contents of samples varied from 0.0558 to 0.0878 g water/g solid and multilayer moisture 0.660 to 1.093 g water/g solid. Smith plots for concentrates with and without sweetened condensed milk showed biphasic behavior with breaks at water activities in the range 0.500–0.660. Malt concentrates and sweetened condensed milk sorbed independently below 0.55 aw and interacted above 0.66 aw.
Biogenic Amines Formation during Malting and Brewing
Authors: IZQUIERDO‐PULIDO M. , MARINÉ‐FONT A. , VIDAL‐CAROU M.C.
Published: August 2006

Biogenic amines (histamine, tyramine, β‐phenylethylamine, serotonin, tryptamine, putrescine, cadaverine, agmatine, spermine and spermidine) in raw materials, worts and beers, and their evolution during brewing were studied using HPLC. Hop and especially malt contributed to amine contents in wort and beer. Amines were not detected in rice, used as adjunct cereal. High amine production was found during malting. Spermine and spermidine levels decreased sharply during mashing, while the other amines increased, except for putrescine that did not vary. No significant changes in formation of amines occurred during fermentation, except for tryptamine and tyramine. Tyramine formed ranged from 9.70 to 27.30 mg/L.
Soy Protein Hydrolysate Debittering by Lysine‐Acetylation
Authors: WON YEOM HAE , KIM KANG SUNG , RHEE JOON SHICK
Published: August 2006

To reduce bitterness of soy protein hydrolyates, chemical modification of lysine was investigated. Isolated soy protein (ISP) was treated with N‐acetylimidazole for acetylation of lysine and tyrosine. 0‐acetyI tyrosine was deacetylated at pH 11. The lysine‐acetylated soy protein and control protein were hydrolyzed by bromelain to the same degree of hydrolysis (10%), and then bitterness of each protein hydrolysate was evaluated. Sensory analyses indicated that bitterness of hydrolysates of lysine‐acetylated ISP decreased in comparison with hydrolysates of control ISP (p<0.005). Surface hydrophobicity of hydrolysates of lysine‐acetylated ISP slightly increased, and they had fewer lysine residues at the C‐terminal region than hydrolysates of control ISP.
Two Colorimetric Assays for Iodine in Foods
Authors: GARWIN JEFFREY L. , ROSENHOLTZ NEAL S. , ABDOLLAHI ABBAS
Published: August 2006

Using a standardized sample preparation, comparisons were made of two colorimetric iodine assays that are based on different chemistry. One assay kinetically measured the initial iodine catalysis of the redox reaction between Ce+4 and As+3. The other monitored iodine catalysis of the reaction between thiocyanate and nitrite by measuring light absorbance after 20 min. Both were accurate when tested with reference samples of nonfat milk powder and oyster tissue that had known certified iodine content. The thiocyanate‐nitrite assay consistently showed greater precision and less variability, particularly at lower iodine concentrations in lyophilized egg samples.
Shear Induced Starch Conversion During Extrusion
Authors: ZHENG XIAOGE , WANG SHAW S.
Published: August 2006

Using a capillary rheometer and a singlerscrew extruder, waxy corn starch was extruded at a relatively low temperature range. Notable conversions induced by shear energy were obtained in very short residence times (from several sec to 1 min). Conversions up to > 70% were also achieved. Kinetic studies showed that conversion caused by shear energy was more efficient than that by thermal energy. The shear rate constant, k, was an exponential function of shear stress and a linear function of shear rate. The minimum shear stress required to cause starch conversion was from 104 to 106 N/m2 for 100°C to 21°C. In such “shear” experiments, the maximum temperature rise due to viscous thermal dissipation, measured experimentally and calculated theoretically, was too low to cause any significant thermal cooking of starch. The shear converted starch extrudates were unpuffed and had shapes of traditional pasta.
Beet Pulp and Isolated Pectin Physicochemical Properties as Related to Freezing
Authors: WANG C. C. H. , CHANG K. C.
Published: August 2006

Any potential effects of postharvest freezing storage of beets on physicochemical characteristics of isolated pectin and beet pulp were determined. Fresh beets were stored at ‐20°for up to 3 mo. At the end of storage, beets were thawed and shredded, and sucrose was extracted. Pectin was isolated using a combination of enzyme treatment and acid extraction. Yield, galacturonic acid content, methoxyl ester content, and molecular mass distributions of the isolated pectin were determined. Neutral and acidic sugar compositions in the nonstarchy polysaccharides (NSP) of the beet pulp were determined using enzyme hydrolysis and gas chromatography. Results showed that physicochemical characteristics of isolated pectin, and sugar composition of the NSP in the beet pulp were not notably influenced by the freeze/thaw cycle.
Unrefined, Dried Apple Pomace as a Potential Food Ingredient
Authors: CARSON K.J. , COLLINS J.L. , PENFIELD M.P.
Published: August 2006

Unrefined pomace of three apple cultivars was dried, powdered, analyzed and evaluated in pie filling and oatmeal cookies. Pomace had 2.2 ‐ 3.3% seed, 0.4 ‐ 0.9% stem, 70.0 ‐ 75.7% apple flesh and 20.1 ‐ 26.4% rice hull as filtering aid (DWB). Average dietary fiber was 36.8% and remaining carbohydrates were 54.4%, totalling 91.2%. Remaining components were protein, fat and ash. Average pH was 4.3; water activity, 0.13; and WHC, 3.7 mL/g. Hunter color was L = 51.8, a = 5.4, and b = 18.2. Two levels of pomace in pie filling or three levels in oatmeal cookies did not affect color, cookie size or sensory scores. Both food products were rated as liked moderately.
Degradation Kinetics of Anthocyanins in Sour Cherry Juice and Concentrate
Authors: CEMEROGLU B. , VELIOGLU S. , ISIK S.
Published: August 2006

The effects of temperature and soluble solids on degradation of anthocyanins in sour cherry concentrate were determined over temperature ranges (‐18 to 37)°and 50 to 80°C. Anthocyanin degradation could be modeled as a first‐order rate reaction, with rates of 33.97 × 10minus;3. hrminus;1 (15°CBrix), 59.19 × 10minus;3. hrminus;1 (45°CBrix) and 97.14 × 10minus;3. hrminus;1 (71°CBrix) at 80°C. Temperature dependence of reaction was described by the Arrhenius relationship. Activation energy for a solids content of 15‐71°C Brix ranged from 16.37‐19.14 kcal.moleminus;1 with an average of 17.45 kcal.moleminus;1
Anthocyanin Pigments: Comparison of Extract Stability
Authors: BAUBLIS ALAN , SPOMER ART , BERBER‐JIMÉNEZ M.D.
Published: August 2006

Stabilities of anthocyanins from Concord grapes, red cabbage, tradescantia and ajuga were studied. RP‐HPLC analysis was used to characterize individual anthocyanins and spectrophotometric analysis for all pigments. Anthocyanins from tradescantia were much more stable than the other extracts. Such increased stability was attributed to its intrinsic nature.
Frozen Dessert Attribute Changes with Increased Amounts of Unsaturated Fatty Acids
Authors: IM J. S , MARSHALL R. T. , HEYMANN H.
Published: August 2006

Vanilla flavor frozen desserts were made to be similar in composition except for the fat. Canola and soybean oils were combined with milk fat to provide fatty acid ratios of 1:1:1 and 3:2:1 (saturated: monounsaturated:polyunsaturated), whereas the milk fat control had a ratio of 24:8.6: 1. Sensory, physical and chemical tests indicated minimal differences between the control ice cream and the dessert with the 3:2:1 ratio. However, product with the 1:1:1 ratio was described as oily and oxidized in flavor. It melted faster, was softer in the penetration test and coarser in texture than the ice cream control.
Wheat Gluten and Glutenin Thermal Conductivity and Diffusivity at Extruder Temperatures
Authors: STRECKER T. D. , CAVALIERI R. P. , POMERANZ Y.
Published: August 2006

Thermal properties (thermal conductivity and diffusivity) of gluten and glutenin were measured in the temperature range 60‐175°typically used in extrusion processing. Thermal conductivity and diffusivity of gluten decreased with increasing temperature and increased with increasing moisture content. Thermal conductivity and diffusivity of glutenin increased with temperature and moisture content. Thermal conductivity of gluten was 0.06‐0.35 W/m‐C and glutenin was 0.29‐0.49 W/m‐C for the temperature range 60‐175°and moisture content range of 0‐30%.
Enzymes Increase Loaf Volume of Bread Supplemented with Starch Tailings and Insoluble Pentosans
Authors: KRISHNARAU L. , HOSENEY R.C.
Published: August 2006

Insoluble pentosans were isolated from starch tailings to study their effect on bread quality. Their incorporation into bread lowered bread quality. Such adverse effects were partially overcome by an optimum level of a pentosanase or an α‐amylase and more completely overcome with a combination of the enzymes. The pentosanase hydrolyzed about 60% of total insoluble pentosans in a solution in 0.5 hr. The solubilized pentosans slightly increased the relative viscosity of the solution.
Acid‐Hydrolyzed Starch Tailings Effects on Cookie Spread
Authors: KRISHNARAU L. , HOSENEY R.C.
Published: August 2006

A starch tailings fraction was isolated from wheat flour and hydrolyzed for various lengths of time with dilute sulfuric acid. Differential scanning calorimetry showed that the hydrolyzed starch tailings were almost as effective as sugars in raising the onset temperature for gelatinization of starch. A sample hydrolyzed 2 hr increased the onset temperature by the same extent as an equal weight of sucrose. When sucrose in cookies was completely replaced by hydrolyzed starch tailing fractions, the spread of the cookies depended on the molecular size of the polysaccharides in the fraction added. Cookies containing a sample hydrolyzed for 0.5 hr had the least spread, whereas those containing starch tailings hydrolyzed for 2 hr spread the most.
Enhanced Inhibition of Listeria monocytogenes by Glycerol Monolaurate with Organic Acids
Authors: OH DEOG‐HWAN , MARSHALL DOUGLAS L.
Published: August 2006

Glycerol monolaurate (ML) inhibition of Listeria monocytogenes was affected by pH and testing matrix. We investigated antimicrobial effects of ML combined with acetic, benzoic, citric, and lactic acids (AA, BA, CA, and LA) on L. monocytogenes in broth medium and crawfish tail meat. Minimum inhibitory concentrations were lower when ML was combined with each acid in dual combination. ML combined with sublethal amounts of AA, BA, or LA gave greater inhibition than for the most active compound alone. No interaction occurred between ML and CA. ML had no influence on pH of media containing organic acids. ML or LA in crawfish tail meat had reduced activity. ML activity was influenced by type of organic acid used. Combining ML with organic acids may provide similar protection to other precooked ready‐to‐eat foods.
Water Concentration/Activity and Loss of Vitamins B1 and E in Pork Due to Gamma Radiation
Authors: FOX JAY B. , LAKRITZ LEON , KOHOUT KAREN M. , THAYER DONALD W.
Published: August 2006

When irradiated, increasing the water content of pork by partial rehydration of freeze‐dried L. dorsi muscle resulted in increasing rate of thiamin loss from zero in dry tissue to ca 6%/kGy of irradiation in tissue with 70% water. Conversely, the rate of loss of α‐tocopherol decreased, from 44%/kGy at 0% to 32%/kGy at 70% water. Decreasing water activity in buffers or in ground or freeze‐dried pork by salt or sucrose had no effect on rate of loss of either vitamin following irradiation. Salt decreased the loss of both vitamins in pork due to competition for the hydroxyl radical by chloride ions.
Static, Controlled (CO2) Atmosphere Packaging of Retail Ready Pork
Authors: HOLLEY R. A. , GARIÉPY C. , DELAQUIS P. , DOYON G. , GAGNON J.
Published: August 2006

Wrapped boneless pork loin roasts and slices were stored at 4°in bulk under constant CO2 concentrations of 50% and 100% for 1 and 2 wks. Samples stored under 50% CO2 for 2 wks could subsequently be displayed (aerobic) for 3 days without becoming unacceptable or for 6 days if previously held under 100% CO2 for 14 days. Aerobic shelf‐life at 4°of the latter samples equalled that of fresh pork chops under simulated retail display. Physicochemical characteristics during storage did not limit acceptability. Reusable master packs have application for distribution of retail ready cuts under controlled atmosphere packaging.
Residence Time Distribution of Multiple Particles in Non‐Newtonian Holding Tube Flow: Statistical Analysis
Authors: SANDEEP K. P. , ZURITZ CARLOS A.
Published: August 2006

Residence times of multiple particles in aqueous solutions of carboxy‐methylcellulose (CMC) in a holding tube arrangement were measured at different conditions of fluid viscosity, suspension flow rate, particle sizes and particle concentrations. Nearly neutrally buoyant polystyrene spheres were used to simulate food particles. Residence time distribution functions, E(t), applicable to lethality calculations in aseptic processing were developed along with equations to predict the mean (RTmean), minimum (RTmin) and standard deviation (RT std) of the residence times as a function of process parameters. Results showed that viscosity, flow rate and particle concentrationhad significant (a = 0.05) effects on RTmean) RT min and RT std while particle size affected only RT std. The ratio of mean residence time to minimum residence time was 1.06 to 1.16.
Enzymatic Treatments and Thermal Effects on Edible Soy Protein Films
Authors: STUCHELL YVONNE M. , KROCHTA JOHN M.
Published: August 2006

The effect of heat and enzymatic treatments on physical and moisture barrier properties of soy protein isolate (SPI) edible films were evaluated at three plasticizer levels. Heat treatment produced a film which was smoother and more transparent than unheated SPI films. Heated films had decreased water vapor permeability (WVP) and increased % elongation at break (%E) and % soluble protein when compared to unheated films. Treatment with horseradish peroxidase provided no further improvement in WVP, but increased tensile strength and % protein solubility and decreased %E. Enzymatic treatment caused protein degradation in addition to crosslinking.
Formation and Stability of Citric Acid‐Sodium Citrate Solid Solutions
Authors: PORZIO MICHAEL
Published: August 2006

Specific molar ratio mixtures of crystalline trisodium citrate dihydrate and citric acid were milled. The resulting materials exhibited amorphous character as determined by differential scanning calorimetry DSC). Reversion of the amorphous solid solutions to stable crystalline states occurred over a time period of weeks to months and was related to molar ratios and component forms.
Texture Evaluation of Ultrafiltered Teleme Cheese
Authors: RAPHAELIDES S. , ANTONIOU K.D. , PETRIDIS D.
Published: August 2006

The texture of traditional and ultrafiltered (UF) teleme cheeses was evaluated using instrumental and sensory texture profile analysis. The UF teleme was made from unheated or heat treated (75°C for 5 minutes) UF milk concentrate. Samples were tested after 2 and 4 mo ripening. Instron variables did not discriminate between the three teleme types but sensory attributes, assessed by a panel discriminated the samples. Weak correlations were obtained between sensory and mechanical variables. Redundancy ordination analysis indicated that textural behavior of each type teleme cheese was characterized by different attributes. Sensory springiness or brittleness, lumpiness and fat content characterized the majority of traditional teleme samples whereas adhesiveness, pH, water soluble and noncasein nitrogen characterized the heat‐treated UF samples.
Thermal Stability and Gel‐Forming Ability of Shark Muscle as Related to Ionic Strength
Authors: CHEN HUI‐HUANG
Published: August 2006

Thermal stability and gel‐forming ability of silvertip, hammer‐head and thresher shark as affected by ionic strength were investigated. Low temperature endothermic peaks (LTEP, between 30 and 44°C) were observed in differential scanning calorimetric (DSC) thermograms of the shark muscles and surimi samples. Increases in ionic strength reduced the thermal stability of surimi as shown by depression of transition temperature, denaturation enthalpies and LTEP. Although gel strength of heat‐treated surimi increased with increasing NaCl concentration, the three species had different sensitivities to ionic strength. The highest NaCl‐induced gel‐forming ability of surimi was achieved at 0.5M salt concentration for silvertip and thresher; at 1.0M for hammer‐head shark.
Functional Properties and Shelf Life of Fresh Surimi from Pacific Whiting
Authors: PIPATSATTAYANUWONG SIRIPORN , PARK JAE W. , MORRISSEY MICHAEL T.
Published: August 2006

Total aerobic plate count (APC), shear stress, shear strain, and color of fresh Pacific whiting surimi stored at 5°C were determined at day 0, 1, 3, 5, and 7. Frozen surimi was prepared with four levels of cryoprotectams (0, 3, 6, and 9%) and was compared with fresh surimi for gelforming ability. Fresh Pacific whiting surimi had a shelf life of 5 days. The gel functionality remained unchanged throughout the storage time. Strain values of fresh surimi were not different from those of frozen surimi with 9% cryoprotectants, but stress values of fresh surimi were almost three times higher than those of frozen surimi.
Biochemical Changes and Sensory Quality of Shredded and MA‐Packaged Iceberg Lettuce
Authors: HEIMDAL HANNE , KÜHN BIRKA FALK , POLL LEIF , LARSEN LONE MELCHIOR
Published: August 2006

Cultivars of shredded iceberg lettuce (Lactuca sativu L.) ‘Saladin’, ‘Santis’, ‘Telda’ and ‘Roxette’ responded in a parallel way to four modified atmosphere (MA) packaging treatments. Moderate vacuum packaging (mvp) in 80 μm polyethylene (PE) inhibited enzymatic browning over 10‐day storage at 5°C. When lettuce was packaged in 80% O2, 20% CO2 (80/20), more browning occured in SL3‐bags (59 μm multilayer coextruded film) than in PE‐bags. Polyphenol oxidase activity declined during storage in all 4 atmospheres, with lowest activity in PE‐80/20. Endogenous ascorbic acid (AA) did not act as an efficient antioxidant in delaying browning. Total carbohydrate content (TC) declined slightly during storage. Tristimulus color measurements correlated highly with visual ratings.
Chilling‐Associated Softening of Tomato Fruit is Related to Increased Pectinmethylesterase Activity
Authors: MARANGONI ALEJANDRO G. , JACKMAN ROBERT L. , STANLEY DAVID W.
Published: August 2006

Mature‐green tomatoes chilled 15 days (5°C; RH >85%) were softer than nonchilled during subsequent ripening (22°C) by both whole fruit and pericarp tissue puncture (p<0.05), but not by flat‐plate compression. No differences in total polygalactnronase (PG) or PG isozyme activity were evident although total activity was greater in nonchilled after 10 days ripening. Softening of nonchilled fruit correlated (p<0.05) with extracted PGI activity, while chilling‐associated softening correlated (p<0.05) with higher initial extracted pectinmethylesterase (PME) activity. Extracted peroxidase remained constant throughout ripening but was greater (p<0.05) in pre‐chilled fruit consistent with chill‐induced membrane dysfunction. Transmission electron microscopy showed the middle lamella from pre‐chilled tomatoes was swollen and less defined. Loss of turgor from translocation of water to the PME‐modified cell wall was suggested to be responsible for softening as a consequence of chilling.
Ascorbic Acid Stability in Ground Asparagus Samples and in Oxalic Acid Extracts
Authors: ESTEVE MARÍA J. , FARRÉ ROSAURA , FRÍGOLA ANA
Published: August 2006

To establish the storage conditions for asparagus preparation before ascorbic acid determination, samples were ground, the mass was divided into three aliquots that were, respectively, stored at 4°C, – 18°C, or extracted with 1% oxalic acid. The extract was further split into aliquots and stored at 25°, 4°, –18° and ‐75°C. Ascorbic acid content was measured at different times of storage by a polarographic method. The rate of degradation increased with storage temperature; the degradation rate was higher in ground samples than in extracts; no significant changes in ascorbic acid content were observed in extracts stored for 7 days at ‐18° or for 90 days at ‐75°C.
Ozone Storage Effects on Anthocyanin Content and Fungal Growth in Blackberries
Authors: BARTH M. MARGARET , ZHOU CEN , MERCIER JULIEN , PAYNE FREDERICK A.
Published: August 2006

Ozone exposure was assessed for storage of thornless blackberries which are prone to fungal decay. Blackberries were harvested and stored for 12 days at 2°C in 0.0, 0.1, and 0.3 ppm ozone. Berries were evaluated for fungal decay, anthocyanins, color and peroxidase (POD) activity. Ozone storage suppressed fungal development for 12 days, while 20% of control fruits showed decay. The main mold was Botrytis cinerea. Ozone storage did not cause observable injury or defects. By 12 days, anthocyanin content of juice was similar to initial levels for all treatments. Surface color was better retained in 0.1 and 0.3 ppm‐stored berries by 5 days and in 0.3 ppm berries by 12 days, by hue angle values. POD was greater in controls and 0.1 ppm samples, and was lowest in 0.3 ppm fruits by 12 days. Ozone storage resulted in market quality extension.
Prediction of 5–MF Formation in an Industrial Apple‐Juice Evaporator
Authors: TONELLI STELLA M. , ERRAZU ALBERTO F. , PORRAS JOSÉ A. , LOZANO JORGE E.
Published: August 2006

The rate of formation of 5‐hydroxymethylfurfural (5‐HMF) in apple juice with soluble solids ranging from 15 to 69°Brix at 100, 104, 108 or 112°C was experimentally determined. Different mechanisms of reaction were proposed and corresponding kinetic models were derived. The model that provided the best fit to experimental data corresponded to a first‐order initiation step, followed by an autocatalytic period limited by consumption of reactants. The resulting kinetic equations were incorporated into the mathematical model of a triple‐effect apple‐juice evaporator. The simulation values obtained for the content of 5‐HMF in the concentrated apple juice were in good agreement with observed industrial levels. From simulation runs 5‐HMF generation was strongly related to the temperature level at the first evaporation effect.
Inhibition of Horse Bean and Germinated Barley Lipoxygenases by Some Phenolic Compounds
Authors: RICHARD‐FORGET FLORENCE , GAUILLARD FRÉDÉRIC , HUGUES MIREILLE , JEAN‐MARC THIRY , BOIVIN PATRICK , NICOLAS JACQUES
Published: August 2006

Phenolic compounds have been repeatedly implicated as potent antioxidants. Efficiency has been frequently estimated by radical scavenging activity and few reports have considered lipoxygenase (LOX) inhibition. Horse bean LOX was inhibited by a range of phenolic acids, gallates and flavonoids. All compounds tested were uncompetitive inhibitors with the exception of flavonol aglycons which were non competitive type. In each class of compounds, inhibition constants were strongly affected by structures. Inhibition patterns of (‐)‐epicatechin on germinated barley LOXs were detailed: (‐)‐epicatechin acted as an uncompetitive inhibitor while (‐)‐epicatechin reduced hydroperoxide formation by its radical scavenging activity and thus limited enzyme activation.
High Pressure Effects on Emulsifying Behavior of Whey Protein Concentrate
Authors: GALAZKA VANDA B. , LEDWARD DAVE A. , DICKINSON ERIC , LANGLEY KEITH R.
Published: August 2006

Oil‐in‐water emulsions (0.4 wt% protein, 20 vol%n‐tetradecane, pH 7) prepared with solutions of pressure‐treated (up to 800 MPa) whey protein concentrate (WPC) as emulsifier give a broader droplet‐size distribution than emulsions made with native untreated protein. There was a decrease in emulsifying efficiency with increasing applied pressure and treatment time. In contrast, pressure treatment of corresponding WPC emulsions made with the native protein had little effect on emulsion stability. In the pressure‐treated emulsion the protein is probably already conformationally modified so that pressure has little additional effect. However, in solution the native structure of the whey protein is modified by pressure resulting in loss of emulsifying efficiency.
Corn Syrup Oligosaccharide Effects on Sucrose Crystallization
Authors: TJURADI P. , HARTEL R.W.
Published: August 2006

The components of corn syrup (oligosaccharides with different degrees of polymerization) have long been hypothesized to have different effects on sucrose crystallization. Corn syrups were fractionated to produce four fractions, each containing a different range of oligosaccharides. Each fraction decreased the solubility concentration of sucrose to the same extent as the original corn syrup, except for the lowest DP fraction which caused a lower sucrose solubility in water. Each fraction also reduced the growth rate of sucrose crystals compared to the pure system. How ever, at equivalent molar levels, all corn syrup fractions had the same effects on reducing crystal growth.
Recovered Protein and Reconditioned Water from Surimi Processing Waste
Authors: LIN TEIN M. , PARK JAE W. , MORRISSEY MICHAEL T.
Published: August 2006

Micro‐ and ultrafiltration were utilized for recovery of proteins and for water recycling from commercial surimi processing waste water. The proteins recovered by microfiltration showed highly functional properties and composition comparable with proteins in regular surimi. Surimi with a substitution (10%) of recovered proteins did not diminish in gel hardness, elasticity, color, or water retention. Aerobic plate count, chemical oxygen demand, protease activity, and turbidity in the surimi waste waters were reduced by ultrafiltration. Results indicated a potential for recovering proteins to extend yield and recycling water.
Ohmic Heating Maximizes Gel Functionality of Pacific Whiting Surimi
Authors: YONGSAWATDIGUL J. , PARK J. W. , KOLBE E. , DAGGA Y. ABU , MORRISSEY M. T.
Published: August 2006

Surimi without enzyme inhibitors containing 78% moisture and 2% NaCl was heated conventionally and ohmically to 90°C after holding at 55°C for 0, 1, 3 and 5 min. Gels heated slowly in a water bath exhibited poor gel quality, while the ohmically heated gels without holding at 55°C showed more than a twofold increase in shear stress and shear strain over conventionally heated gels. Degradation of myosin and actin was minimized by ohmic heating, resulting in a continuous network structure. Ohmic heating with a rapid heating rate was an effective method for maximizing gel functionality of Pacific whiting surimi without enzyme inhibitors.
Volatile Components in Salt‐Fermented Fish and Shrimp Pastes
Authors: CHA Y.J. , CADWALLADER K.R.
Published: August 2006

Volatile compounds in salt‐fermented anchovy, big‐eyed herring, hair tail viscera, and shrimp pastes were compared by simultaneous steam distillation‐solvent extraction/gas chromatography/mass spectrometry (SDE/GC/MS). A total of 155 volatile compounds were detected. Of these, 111 were positively identified consisting mainly of aldehydes, ketones, alcohols, esters, aromatics, nitrogen‐, and sulfur‐containing compounds. Lipid‐derived components, such as aldehydes, alcohols, and esters, comprised the majority of volatile compounds from fish pastes, while heterocyclic nitrogen‐containing compounds, such as pyrazines, were predominant in shrimp paste.
Edible Coatings on Frozen King Salmon: Effect of Whey Protein Isolate and Acetylated Monoglycerides on Moisture Loss and Lipid Oxidation
Authors: STUCHELL YVONNE M. , KROCHTA JOHN M.
Published: August 2006

Whey protein isolate (WPI) and acetylated monoglyceride (AMG) coatings were evaluated for effectiveness against moisture loss and lipid oxidation of frozen King salmon. A model gel material was also used to screen coatings for effectiveness against moisture loss. Coatings of low‐melting‐point AMG used alone or after applying WPI solution or WPI powder were effective in reducing the rate of moisture loss by 42–65% during the first 3 wk of storage. Onset of lipid oxidation was delayed and peak peroxide values were reduced in samples coated with WPI solution/antioxidant overspray or those containing low‐melting‐point AMGs. No differences in effectiveness were found among the coating treatments.
Particle Size and Mixing Time Effects on Sensory and Physical Properties of Low‐fat, High‐moisture Pork Frankfurters
Authors: SMALL A.D. , CLAUS J.R. , WANG H. , MARRIOTT N.G.
Published: August 2006

Changes in particle size affected measured characteristics more than changes in mixing time. Sensory results indicated that use of a 2.0 mm plate produced the coarsest (P<0.05) product. CIE b* values decreased (<0.05) as particle size was increased. Products produced with a 2.0 mm plate compared to a 1.4 mm plate had higher (P<0.05) hardness values and total energy to shear. Particle size did not affect (P>0.05) cooking loss, springiness, cohesiveness, or chewiness. Additional mixing tended to decrease sensory particle size and increase springiness and chewiness.
Sensory Characteristics of Frankfurters as Affected by Salt, Fat, Soy Protein, and Carrageenan
Authors: MATULIS RICHARD J. , McKEITH FLOYD K. , SUTHERLAND JOHN W. , BREWER M. SUSAN
Published: August 2006

Continuous variables, salt, fat, and either soy protein or iota‐carrageenan, were evaluated using response surface methods to formulate a lower salt/ lower fat franktirter with acceptable palatability attributes. Soy protein increased hardness and off‐flavor, and decreased juiciness, saltiness, and flavor intensity. Soy protein should be added to frankfurters at < 3.0% to minimize this effect. Carrageenan increased hardness at low salt concentrations (below 1.7%) and decreased juiciness at fat concentrations > 15%. Flavor intensity increased as carrageenan and fat level increased at 1.3% salt. At 1.65% salt, off‐flavor intensity decreased as fat content increased and carrageenan decreased.
Variations in Radiation Sensitivity of Foodborne Pathogens Associated with the Suspending Meat
Authors: THAYER D.W. , BOYD G. , FOX J.B. , LAKRITZ L. , HAMPSON J.W.
Published: August 2006

Longissimus dorsi from beef, pork, and lamb and turkey breast and leg meats were inoculated with Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus, and the gamma radiation resistance of the pathogens were determined under identical conditions. At 5°C the respective radiation D‐values of E. coli O157:H7 and L. monocytogenes did not vary with the suspending meat. The D‐value for a mixture of Salmonella spp. was significantly lower on pork than on beef, lamb, turkey breast, and turkey leg meats. The D‐value for S. aureus was significantly lower on lamb and mechanically deboned chicken meat than on the other meats. All values were, nevertheless, within expected ranges.
Quality Characteristics of Restructured Beef Steaks Manufactured by Various Techniques
Authors: RAHARJO S. , DEXTER D.R. , WORFEL R.C. , SOFOS J.N. , SOLOMON M.B. , SHULTS G.W. , SCHMIDT G.R.
Published: August 2006

Beef (9–11% fat) was restructured with each of six mechanical treatments including chunking, fiberizing, slicing, chunking + slicing, slicing + water, and tenderizing each in combination with addition of 0.5% sodium chloride (salt)/0.5% phosphate, 0.5% Na‐alginate/0.5% Ca‐lactate, 0.5% Na‐pectate/0.5% Ca‐lactate, or no additives (control). Beef steaks restructured with salt/phosphate had lower (P<0.05) purge losses: higher binding force and bind scores than control products. Steaks restructured with Na‐alginate/Ca‐lactate had lower cooking losses and higher bind scores than controls. Use of Na‐pectate/Ca‐lactate did not improve (P>0.05) purge loss, cooking loss, binding force or sensory properties. Chunked meat or mixtures of chunked and sliced meats in combination with salt/phosphate or Na‐alginateica‐lactate resulted in steaks with acceptable bind and textural properties.
Volatiles and Sensory Characteristics of Cooked Egg Yolk, White and Their Combinations
Authors: WARREN M.W. , LARICK D.K. , BALL H.R.
Published: August 2006

Headspace volatiles were produced by heating fresh egg yolk, white and different ratios of yolk to white. Volatiles of the same treatments produced during steam distillation extraction were identified, compared, and related to sensory characteristics of fresh scrambled eggs. Overall impression, sulfur, and sweet notes were sensory characteristics identified to distinguish between samples with varying yolkwhite ratios. Volatile concentrations of compounds in the headspace, and steam distillation/ solvent extracts were used to distinguish between scrambled eggs with different yolk:white ratios. The concentration of both egg yolk and white had a significant effect on fresh scrambled egg sensory characteristics and flavor volatiles. The contribution of both must be considered when producing egg substitutes.
Programmed Freezing Affects Texture, Pectic Composition and Electron Microscopic Structures of Carrots
Authors: FUCHIGAMI MICHIKO , HYAKUMOTO NORIKO , MIYAZAKI KOICHI
Published: August 2006

Raw and blanched carrots (3 min, boiling water) were frozen at −2°C, −3°C, −4°C or −5°C/min (final −20°C or −50°C) then thawed at 20°C or 100°C. Firmness of thawed raw carrots was: −5°C > −4°C > −3°C > −2°C/min. Effect of freezing rate on blanched carrots was less than that on raw carrots, but firmness of thawed carrots was not affected by final temperature of freezing. When raw carrots were thawed at 20°C, high methoxyl pectin decreased. Pectin decrease in blanched carrots caused by freezing was greater than that in frozen raw carrots. Effects of slow‐freezing, programmed‐freezing (slow + quick + slow) and quick‐freezing showed quick freezing (—5°C/min) best for texture. As freezing rate decreased, drip increased. A wide difference among experimental samples in fine structure was revealed by cryo‐scanning electron microscopy.
Sensory Attributes and Instrumental Analysis Relationships for Strained Processed Carrot Flavor
Authors: HOWARD L.R. , BRASWELL D. , HEYMANN H. , LEE Y. , PIKE L.M. , ASELAGE J.
Published: August 2006

Regression models relating sensory attributes and composition of tin genotypes of processed strained carrots were developed. Fresh carrot‐flavor, aroma, and aftertaste were associated with high total sugar to terpinolene ratios. Sweet taste and sweet aftertaste were associated with high levels of total sugar and high total sugar to terpinolene ratios. Cooked flavor and cooked aftertaste were associated with high terpinolene content. Selection of genotypes with high total sugar to terpinolene ratios should improve strained processed carrot sensory quality.
Texture and Pectic Composition Differences in Raw, Cooked and Frozen‐Thawed Chinese Cabbages due to Leaf Position
Authors: FUCHIGAMI MICHIKO , HYAKUMOTO NORIKO , MIYAZAKI KOICHI
Published: August 2006

Differences in texture of raw, cooked and blanched‐frozen‐then‐thawed Chinese Cabbages and their leaf positions (10, 20, 30, 40, or 50th midribs from the outside) were investigated. Firmness and rupture strain of raw midribs were low, but increased after short cooking time. Crispness of tissues decreased and elasticity increased. The 20–30th midribs were slowest to soften during cooking, while the inner midribs from the 40th were more readily softened. The 40th contained more high methoxyl pectin than did the 20th. Therefore, they were more quickly softened because of pectic release by transelimination. After freezing‐thawing, firmness decreased and rupture strain increased. Midribs with firmer texture contained more pectin. After freezing‐thawing, amounts of pectin in midribs decreased.
Wheat Flour Protein Concentrate Characterization by Biochemical, Physicochemical and Baking Tests
Authors: CZUCHAJOWSKA Z. , KAWKA A. , PASZCZYNSKA B. , POMERANZ Y.
Published: August 2006

Protein concentrates before and after defatting from hard and soft wheat flours by water and 1% NaCl solution were characterized by lipid, sodium dodecyl sulphate (SDS) sedimentation, solubility, and breadmaking. Sedimentation values were higher for hard wheat flours than for soft, and in both about three times higher than in separated glutens. Solubility of proteins in SDS was reduced from ∼23 to 31% in flours to ∼3 to 19% in gluten concentrates. Defatting did not affect electrophoretic patterns but indicated lowered protein extractability. Gliadins and HMW glutenins were lower in extracts of separated glutens than in the extracts of doughs. Protein concentrates from fractionation with 1% salt solution, differed widely from those separated with water. This especially affected water absorption, dough development, and baking performance.
Spray Drying of Lactococcus lactis ssp. lactis C2 and Cellular Injury
Authors: FU WAN‐YIN , ETZEL MARK R.
Published: August 2006

Starter cultures were spray‐dried at five outlet‐air temperatures using four concentrations of cells in the feed solution. Powders made using the lowest outlet‐air temperature and the highest cell concentration had the highest viability. Storage at 4°C for 3 mo caused a 34–86% loss of viability. Cellular injury resulted from dehydration, and exposure to high temperatures in the atomizer and during droplet drying. Lactic acid production was similar for frozen, freeze‐dried and spray‐dried cultures made from a single cell paste. The lag time before lactic acid production was apparently an inherent characteristic of each specific cell paste.
Permeability and Diffusivity of d‐Limonene Vapor in Polymeric Sealant Films
Authors: KOBAYASHI MASAYOSHI , KANNO TOHRU , HANADA KATSUTOSHI , OSANAI SHIN‐ICHI
Published: August 2006

The permeability (P) and Diffusivity (D) of d‐limonene vapor in nine polymeric sealant films were measured and compared at a vapor concentration of 0.719 mg/L over the range 25–45°C. The sorption of d‐limonene (qs) was determined by a temperature programmed desorption (TPD) method. Equations to predict P and D for the different films were derived as a function of qs or temperature (Tmp) of differential scanning calorimeter measured melting points (DSCmp) of the films. Results indicated a tendency of test films with smaller values of qs and higher Tmp to have higher barriers against loss of d‐limonene due to absorption.
Zymogen Activation in Pancreatic Endoproteolytic Preparations and Influence on Some Whey Protein Hydrolysate Characteristics
Authors: MULLALLY MARGARET M. , O'CALLAGHAN DANIEL M. , FITZGERALD RICHARD J. , DONNELLY W.J. , DALTON JOHN P.
Published: August 2006

A proteolytic preparation from porcine pancreas was isolated. Trypsin, chymotrypsin and elastase were characterized and their time‐dependent stability at 37°C was studied. The supematant of a 30% (w/v) saturated ammonium sulfate precipitation of a pancreatic extract (30S) was developed to pilot‐scale level. The influence of zymogen activation time on molecular characteristics of whey protein hydrolysates produced by 30S and the commercial pancreatic preparation Corolase PP were compared. Amino acid analysis and gel permeation chromatography were used to characterize lactalbumin hydrolysates produced. Physicochemical characteristics of whey protein hydrolysates could be altered by manipulation of zymogen activation conditions in pancreatic proteinase preparations to be used during subsequent protein hydrolysis.
Phytic Acid Protective Effect Against Beef Round Muscle Lipid Peroxidation
Authors: LEE BEOM JUN , HENDRICKS DELOY G.
Published: August 2006

Phytic acid, constituting 1–5% of many plant seeds and cereals, can form iron‐chelates and inhibit lipid peroxidation. We measured thiobarbituric acid reactive substances (TBARS), an indication of lipid peroxidation, in beef homogenates to investigate the effects of phytic acid with various homogenizing buffers and at different pH levels. Phytic acid effectively inhibited either iron‐induced or non‐iron‐induced lipid peroxidations. The effect of phytic acid was dose‐ and pH‐dependent. Such inhibition of lipid peroxidation may help prevent deterioration of food quality.
Storage Stability of Vacuum Packaged Frozen Pork Sausage Containing Soy Protein Concentrate, Carrageenan or Antioxidants
Authors: HO C.P. , HUFFMAN D.L. , BRADFORD D.D. , EGBERT W.R. , MIKEL W.B. , JONES W.R.
Published: August 2006

Fresh pork sausage patties containing carrageenan, without or with soy protein and an antioxidant were packaged with or without vacuum. They were evaluated for sensory properties, visual color, thiobarbituric acid reactive substances (TBARS), and Hunter color ‘L’, ‘a’, ‘b’ values at 4‐wk intervals during 16 wk frozen storage. Rosemary extract was as effective as butylated hydroxytoluene (BHT)/propyl gallate (PG)/citric acid (CA) in antioxidant properties, but patties with BHT/PG/CA showed less surface discoloration (P < 0.05). In fat‐control (FC) products, antioxidants combined with vacuum packaging provided optimum protection against rancidity. With vacuum packaging (VP), reduced‐fat products maintained acceptable quality (TBARS and sensory properties) during 16 wks frozen storage.