bluuebunny/crossref_metadata_2025 huggingface dataset:
Computer Simulation of the Attrition Patterns of Particulated and Agglomerated Foods
Authors: PELEG M. , NORMAND M.D.
Published: August 2006

Attrition processes were simulated using a set of mathematical expressions that describe the bimodal size distribution of the attrited particles and their temporal relationships. It is demonstrated that the dominance of a particle shattering mechanism or surface erosion as well as any of their combinations can be described in terms of the magnitude and ratios of only three empirical parameters, provided the initial conditions and other physical characteristics of the system are known.
Sugar Composition of Cucumber Cell Walls During Fruit Development
Authors: McFEETERS R. F. , LOVDAL L. A.
Published: August 2006

The sugar composition of pickling cucumber cell walls was analyzed in seven cucumber sizes. Relative to total cell wall sugars, glucose did not change, while the other major neutral sugars, galactose, xylose and mannose, underwent relatively small declines during fruit development. The ratios of galacturonic acid/rhamnose and galacturonic acid/arabinose showed large increases during fruit growth, which indicated that pectin structure may change. Pectin methylation in the mesocarp tissue increased from 35 to 64% as cucumber fruit matured. A positive correlation was observed between the firmness of cucumber mesocarp tissue and the total amount of cell wall sugars in the fresh tissue. Cucumber peel tissue contained 4 to 5‐fold higher sugar concentrations than either the mesocarp or endocarp tissues.
Lipoxygenase lsoenzymes in Soybeans: Effects on Crude Oil Quality
Authors: ENGESETH N. J. , KLEIN B. P. , WARNER K.
Published: August 2006

Crude oils prepared from tempered or untempered Amsoy, Calland, and lipoxygenase‐1 null soybeans were stored under accelerated conditions and examined for peroxide value and sensory characteristics. Activity of three lipoxygenase isoenzymes was reduced by two of three tempering methods; steaming under pressure was most effective. However, with the exception of pressure steam‐tempered Calland beans, lipoxygenase was not completely inactivated. Peroxide values of stored oils were significantly higher than those of oils that were not stored. Cultivar differences were observed. Flavor scores for crude oils from tempered beans were not markedly different. Grassy/hay and roasted flavors were more predominant in oils from tempered than untempered beans. Tempering procedures had more effect on quality of crude soybean oils than cultivar.
Formation of a Gel from a Heated Emulsion of Alfalfa Leaf Protein and Peanut Oil
Authors: BARBEAU WILLIAM E. , KINSELLA JOHN E.
Published: August 2006

A new method was investigated for extracting the proteins from green leaves (alfalfa). An opaque white gel formed when an emulsion of chloroplast‐free leaf tissue juice and peanut oil was heated for 10 min at 90°C. The proximate composition of this gel was 40% moisture, 2% protein, 57% fat, 0.2% ash, and <1% carbohydrate. SDS‐PAGE analysis of the gel suggested that fraction 1 or ribulose bisphosphate carboxylase is the major protein component present. The apparent viscosity of the gel, 5,257 m Pa.sec, was less than one‐tenth of mayonnaise.
Nonenzymatic Browning in Liquid Model Systems of High Water Activity: Kinetics of Color Changes due to Caramelization of Various Single Sugars
Authors: BUERA M. del PILAR , CHIRIFE JORGE , RESNIK SILVIA L. , LOZANO ROBERTO D.
Published: August 2006

The kinetics of color changes due to caramelization of various single sugar solutions (fructose, xylose, glucose, maltose, lactose, and sucrose) of water activity adjusted to 0.90 (by adding NaCl) and heated at various temperatures (45–65°C) was studied. A zero‐order and a “mixed”‐order kinetic model were satisfactorily used to describe the rate of color formation. Fructose and xylose solutions browned much more rapidly than those of maltose, glucose, lactose or sucrose. Activation energies for color development of fructose and xylose were in the range 25–30 kcal/mole, while for lactose and maltose they were 35–48 kcal/mole. Lowering of pH inhibited caramelization browning of sugar solutions. The role of hydrolysis in the browning of heated sucrose solutions was studied.
Nonenzymatic Browning in Liquid Model Systems of High Water Activity: Kinetics of Color Changes due to Maillard's Reaction Between Different Single Sugars and Glycine and Comparison with Caramelization Browning
Authors: BUERA M. Del PILAR , CHIRIFE JORGE , RESNIK SILVIA L. , WETZLER GRACIELA
Published: August 2006

Sugar‐ (fructose, xylose, glucose, lactose, maltose, sucrose) glycine solutions of water activity adjusted to 0.90 (by adding NaCI) were heated at 45–65°C. The behavior of fructose‐glycine solutions was well described by a zero‐order reaction model, but for the other sugars a fractional‐order (∼ 0.5) kinetic model was necessary. Activation energies for glucose, fructose and sucrose systems were 25.7, 29.3 and 36.6 kcah/mole, respectively. At pH 6 the descending order for color development was xylose > glucose > fructose > lactose > maltose > sucrose; at pH lower than 6 fructose browned faster than glucose. The role of hydrolysis of sucrose as related to Maillard's browning of heated sucrose‐glycine solutions was studied. Caramelization browning seemed to contribute noticeably to total color development only in fructose‐glycine solutions.
A Method for the Measurement of Foam Formation and Stability
Authors: PHILLIPS L. G. , HAQUE Z. , KINSELLA J. E.
Published: August 2006

A whipping method for the measurement of overrun and foam stability was developed. Using this method the characteristic foams formed by the following proteins were studied: sodium caseinate, milk protein isolate and whey protein. The method was able to detect differences between foams produced by different proteins. The effects of copper sulfate and proteose‐peptone on egg white foams were studied to show the reliability of the method. It was demonstrated that the addition of ImM copper sulfate stabilized (p < 0.05) foams made from both fresh and powdered egg white. Addition of proteose‐peptone (0.05% and 0.1%) reduced the overrun and destabilized egg white foams.
CIostridium botulinurn Spore Gerrnination, Outgrowth, and Toxin Production Below pH 4.6; Interactions Between pH, Total Acidity, and Buffering Capacity
Authors: YOUNG‐PERKINS KATHLEEN E. , MERSON R. LARRY
Published: August 2006

The effect of soy protein concentration on Clostridium botulinurn spore germination, outgrowth, and toxin production in the presence of varying levels of inorganic (HCI) and organic (citric) acids was investigated. Media were blended using deoxygenated soy concentrate (1–7% protein), acidified with deaerated acids to effect post‐autoclaving pH values of 4.1, 4.3 and 4.5, and inoculated with C. botulinum Type A spores. All manipulations were conducted under conditions of strict anaerobiosis (0–2 ppm atmospheric oxygen, media Eh7 values of < — 345 mV). Germination, proliferation, active motility, and elaboration of neurotoxin occurred as low as pH 4.07. Titratable acidity, which accounted for the soy protein buffering capacity, appeared to define toxicity endpoints as pH alone could not.
Identification of Additional Volatile Compounds from Cbntaloupe
Authors: HOW/AT R. J. , SENTER S. D.
Published: August 2006

The volatile components of cantaloupe pericarp were analyzed during ripening by gas‐liquid chromatography‐mass spectrometry. Thirty‐two compounds were identified from concentrates prepared by steam distillation‐solvent extraction of the volatiles. Eight of the constituents including ethyl (methylthio) acetate, (Z)‐6‐nonenyl acetate, (Z, Z)‐3,6‐nonadienyl acetate, benzyl propionate, benzyl alcohol, a sesquiterpene hydrocarbon, cinnamyl acetate and an isomer of 3,4‐dimethoxyacetophenone have not been identified previously. Headspace analysis of cantaloupe samples at six stages of maturity showed increases in total ethyl and acetate esters, acetaldehyde, ethyl acetate, and ethanol with maturation. Levels of these compounds remained low and relatively constant until the breaker stage and thereafter increased rapidly until the fruit was fully mature.
Determining the Degree of Freshness of Rainbow Trout (Salmo gairdneri) Cultured in Brackish Water
Authors: TESKEREDZIĆ ZLATICA , PFEIFER KLARA
Published: August 2006

Rainbow trout were kept in cages in brackish water for 40 and 90 days, respectively, to establish how brackish water affected sensory characteristics and the concentration of TMA. The trout from both groups were transferred to the sea at the same time. During the first 3 days of the experiment no differences in sensory characteristics and TMA were noted in the fish, but after that period TMA increased and the sensory characteristics of the fish from all three groups changed so much that they were no longer suitable for human consumption. The results suggested an upper acceptable limit of TMA in trout for human consumption of around 10 mg%.
Electrophoretic Identification of Raw and Cooked Shrimp using Various Protein Extraction Systems
Authors: AN H. , MARSHALL M.R. , OTWELL W.S. , WEI C.I.
Published: August 2006

Proteins were extracted from raw or cooked pink (Penaeus duorarum), white (Penaeus setiferus) or rock shrimp (Sicyonia brevirostris) with five different solutions: water, water homogenate adjusted to pH 8.0, 0.1M NaCl, 1% SDS, or 8M urea. Each extract from each species was analyzed using sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE). Water extraction showed highly species‐specific banding patterns for raw shrimp, while patterns for SDS extracts were not as species‐specific. However, SDS extracts provided the greatest information on species variation of cooked shrimp. SDS‐PAGE was useful in distinguishing shrimp of different genus. This technique was tested and proven in a blind study to be useful for species identification and detection (within 10% of actual amount) of fabricated products.
Packaging of Scallops with Sorbate: An Assessment of the Hazard from Clostridium botulinum
Authors: FLETCHER G.C. , MURRELL W.G. , STATHAM J.A. , STEWART B.J. , BREMNER H.A.
Published: August 2006

Toxin production in shucked scallops by a mixture of 10 strains of Clostridium botulinum (types A, B, E, F) was studied using mouse bioassay. Scallops, with or without 0.1% potassium sorbate, were packaged in air‐permeable film or vacuum packaged in impermeable film. Two trials were done in which packages were inoculated with different spore levels and held at 4°, 10° and 27°C. Bacterial counts were made on various selective media. Only type A toxin was observed and this only in evacuated packages held at 27°C. Toxin developed more rapidly in the presence of sorbate. All packages in which toxin was recorded had offensive odors and were visibly spoiled. The potential hazard from botulism is discussed.
Effect of Freezing and Frozen Storage of Alaska Pollock on the Chemical and Gel‐Forming Properties of Surimi
Authors: SCOTT D.N. , PORTER R.W. , KUDO G. , MILLER R. , KOURY B.
Published: August 2006

Alaska pollock was headed, gutted, and frozen at sea in pre‐ and postrigor condition. Surimi made from this fish held at ‐ 29°C showed a gradual loss in gel‐forming ability with time of storage. This loss in gel‐forming ability was accompanied by a loss in viscosity and Ca++‐ATPase activity of the surimi over the 9‐month storage period. The gel strength of kamaboko gels showed an inverse linear relationship with gel moisture over a limited moisture range. Simply freezing and thawing pollock resulted in surimi with significantly lower gel strength than that from fresh pollock.
A Generalized Model for Predicting Heat‐Induced Chicken Myofibrillar Protein Gel Strength
Authors: SMITH D.M. , ALVAREZ V.B. , MORGAN R.G.
Published: August 2006

A generalized mathematical model was developed for predicting effects of temperature‐time history (TTH), protein concentration, and pH on the strength of heat‐induced chicken myofibrillar protein gels. A pseudo first‐order kinetic model was used to describe integral TTH effects of protein denaturation on an apparent viscosity index. A reaction threshold temperature of 30°C and a denaturation activation energy of 20 kcal/mole were calculated. No significant increase in viscosity index was observed at TTH values above 1.0 × 1010oK‐sec. Maximum viscosity index was observed at pH 6.0. The effect of protein concentration on viscosity index was modeled as a logarithmic function. An a priori modeling approach based on fundamental theories can be used to predict the strength of gels under various processing conditions.
Influence of Smokehouse Air Flow Patterns, Air Changes and Cook Cycles on Texture and Shrinkage of Wieners
Authors: STECH I. , USBORNE W.R. , MITTAL G.S.
Published: August 2006

The effects of two air flow systems, four air changes, and three cook cycles on shrinkage and texture of wieners were investigated. The interaction between air flow patterns and cook cycles was significant for shrinkage revealing the highest weight losses for a low relative humidity cook cycle when combined with the vertical air flow. The interaction of air flow pattern and number of air changes for the texture profile analysis showed significantly higher results for hardness, gumminess, and chewiness when processed at 56 air changes per minute using vertical air flow than for any other combination of treatments. Air changes significantly affected shrinkage and Warner‐Bratzler shear values producing higher values with an increase in the number of air changes.
Microbiological Quality of Cowpea Paste Used to Prepare Nigerian Akara
Authors: BULGARELLI M.A. , BEUCHAT L.R. , McWATTERS K.H.
Published: August 2006

Cowpea (Vigna unguiculata) paste used to prepare akara was collected from three Nigerian marketplaces and analyzed to determine populations and predominant types of bacteria, yeasts, and molds. Total aerobic microbial populations were initially high (106‐108/g) and increased after 12 hr incubation at 30–32°C to ca. 109/g. Initial coliform populations were 102‐104/g and decreased slightly between 6 hr and 12 hr; yeast/mold populations remained constant at 104‐105/g. The average initial pH of 6.0 declined to 5.1 and 4.5 after 6 hr and 12 hr incubation, respectively. Predominant bacteria consisted of Enterobacter, Klebsiella, and Lactobacillus species; Candida species and Aspergillus mger were the predominant fungi isolated from the pastes.
Effects of Heat Treatments on the Head Yields of High Moisture Rough Rice
Authors: REYES V.G. , JINDAL V.K.
Published: August 2006

The influence of high temperature heat treatments on the head yields of rough rice having moisture in the range 18–30% wet basis was investigated using an experimental rotary conduction heating unit with constant agitation. Based on the time‐temperature history of bulk grain, reaction kinetic parameters (Fc and zc values) were determined for specified changes in head rice yields for general application. The estimated isothermal heating times (Fc values) were related to the reference bulk grain temperatures (Tref) and initial moisture of rice samples (IMC). The plots of Fc value and Tref led to the determination of zc value and its dependence on the IMC of rough rice.
Quality of Frozen Cauliflower during Storage
Authors: APARICIO‐CUESTA M.P. , GARCIA‐MORENO C.
Published: August 2006

A study was conducted on the changes occurring in vitamin C content in frozen cauliflower stored under different conditions. During storage at ‐22°C, 25% vitamin C was lost after 13 months and 62.2% after 30 months. An acceptable sensory quality was conserved for 10 months; after this time, a decrease began in the characteristic flavor. Storage in a display freezer did not affect vitamin C; however, storage with temperature fluctuations was very harmful, especially regarding sensory characteristics.
Potentiall of Ferulic Acid as a Precursor to Off‐Flavors in Stored Orange Juice
Authors: NAIM M.ICHAEL , STRIEM B.ENJAMIN J. , KANNER J.OSEPH , PELEG H.ANNA
Published: August 2006

The hypothesis that free ferulic acid in stored orange juice contributes to the objectional aroma of p‐vinyl guaiacol (PVG) was tested. Single‐strength orange juice (SSOJ) contained 185 μg/L free ferulic acid which increased to 316 μg/L after pasteurization. Commercial samples of SSOJ contained 3.7mg/L free ferulic when incubated at 35°C for 28 days; incubation at 50°C, resulted in 9.5 mg/L, while samples kept at 4°C contained 2.9 mg/L. Simultaneously, PVG content in SSOJ increased by 2‐(35°C) to 3‐(50°C) fold, while addition of ferulic acid accelerated formation of PVG. Inclusion of orange juice with added ferulic acid, produced a less acceptable aroma (laboratory taste panel) than juice incubated without added ferulic acid.
Reduction of Grapefruit Bitter Components in a Fluidized β‐Cyclodextrin Polymer Bed
Authors: WAGNER C. J. , WILSON C. W. , SHAW P. E.
Published: August 2006

The bitter components limonin and naringin in grapefruit juices were reduced by β‐cyclodextrin polymer with pilot plant equipment using a fluidized bed process. This polymer has been regenerated 21 times without apparent loss in capacity. Reduction of limonin and naringin concentrations ranged from 30–59% and from 33–48%, respectively. Both limonin and naringin levels were reduced sufficiently in all juices to make them significantly preferred in flavor tests over their controls.
Short‐Time Breadmaking Systems. Effect on Oxidation
Authors: MANINGAT J. I. , WU J.Y. , HOSENEY R.C. , PONTE J.G.
Published: August 2006

A spread test was used to study the effects of fermentation time and various agents on dough. Short fermentation times (15–30 min) greatly improved spread ratio. Yeast also improved spread ratio, particularly in combination with time. A combination of 60 ppm KBrO3 and 100 ppm ascorbic acid was the most effective oxidant system. There was an obvious interaction between yeast and oxidants. Loaf volume was not affected by the timing of addition of yeast or ascorbic acid to dough. Potassium bromate was more effective when added at the premix. A 60 min rest between premix and remix consistently gave higher loaf volume when yeast was added, but not when both yeast and oxidants were present.
Hierarchy in Food Colorants Absorbtion on Selected Crystalline Powders
Authors: SAPRU V. , PELEG M.
Published: August 2006

Three food colorants, namely FD&C Blue No. 1, Red No. 40, and Yellow No. 5, were absorbed on glass beads and reabsorbed on powdered citric acid, malic acid, sucrose, and sodium chloride. At water activities below 0.58, the migration pattern of the pigment from the original host to a fresh carrier, of the same or different chemical species, served as a measure of the relative surface affinity between the pigment and the host powder. The pigments showed maximum affinity to citric acid and to a somewhat lesser extent to malic acid and sucrose. Their affinity to sodium chloride was the least intensive. Small particle size increased the interparticle affinity of dry powders. At water activities higher than a critical water‐activity region (between 0.33–0.58), all pigment migration practically came to a halt, probably as a result of stabilization of the pigment‐carrier agglomerates by liquid bridges.
Analysis and Quantitation of Minor Di‐ and Trisaccharides in Honey, Using Capillary Gas Chromatography
Authors: LOW N.ICHOLAS H. , SPORNS P.ETER
Published: August 2006

Methodology is introduced to separate and quantitate most of the di‐ and trisaccharides composed of glucose and fructose moieties, found in honey. At least twelve closely related disaccharides and seven trisaccharides were successfully identified and quantitated employing a combination of reduction and trimethylsilylation followed by either temperature programmed (disaccharides) or isothermal (trisaccharides) gas chromatography. The oligosaccharides in honey, representing approximately 3% of the total sugars, could be isolated using preparative HPLC and analyzed using the aforementioned gas chromatographic methodology. In addition, these oligosaccharides could also be analyzed without employing a preparative HPLC separation by using a concomitantly larger sample volume. Palatinose, not previously reported in honey, was found in many honey samples.
Theoretical Computation of the Isothermal Flow Through the Reverse Screw Element of a Twin Screw Extrusion Cooker
Authors: TAYEB J. , VERGNES B. , VALLE G. DELLA.
Published: August 2006

A mathematical model of the flow of molten starch through the reverse screw element of a twin screw extrusion‐cooker was proposed. The assumptions included isothermicity, Newtonian flow in each part of the reverse screw element and quasi‐steady geometry. The theoretical approach is based on solving Stokes equations in the direct screw element and then on writing flow rate conservation in each part of the reverse screw element. The various flow rates, the pressure drop and the residence time distribution through the reverse screw element were computed for a CLEXTAL BC 45 twin screw extruder under different operating and geometrical conditions; good agreement was found when comparing these results with previous experimental work. The pressure drop through the reverse screw element was low (0.5–1.0 MPa); the flow rates in the different channels of the reverse screw element were important compared to the total feed rate of the extruder (two to three times larger) which might explain the broadening of the residence time distribution in the reverse screw element.
Differentiation between Helix and Achatina Snail Meat by Gel Electrophoresis
Authors: BRACCHI P.IER GIOVANNI.
Published: August 2006

Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and photodensitometry of foot muscle proteins in Helix (Helix pomatia) and Achatina (Achatina fulica) demonstrate a distinctive pattern in the low molecular weight region between the two species examined. Muscle proteins from Helix showed two distinguishing bands of 18,000 and 16,000 daltons, while Achatina showed only a single band (18,000 daltons). This distinguishing feature was also evident when the foot muscles were heated at 120°C for 30 min. It is proposed that the difference in this simple pattern of low molecular weight proteins might be used as a tool to differentiate Helix meat from Achatina meat in raw, frozen, and cooked samples.
Effect of Postmortem Storage on Titin and Nebulin in Pork and Poultry Light and Dark Muscles
Authors: PAXHIA J.M. , PARRISH F.C.
Published: August 2006

Purified myofibrils were prepared from samples of chicken breast and thigh muscles and from light and dark portions of pork semitendinosus muscle at death and after storage at 4° and 22°C for 1, 3, and 7 days postmortem. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) was used to examine the effect of postmortem storage of muscle on titin and nebulin. Results indicated that titin and nebulin were more rapidly degraded in light than in dark chicken muscle. In contrast, titin and nebulin were more rapidly degraded in dark than in light pork muscle.
Effects of Chilling Method on the Sensory, Chemical and Cooking Characteristics of Ground Beef Patties
Authors: ABU‐BAKAR A. , REAGAN J.O. , VAUGHTERS H.M. , CAMPION D.R. , MILLER M.F.
Published: August 2006

Hot‐boned beef (excised 90 min postmortem) was chilled either by mixing coarse ground beef with CO2 snow or by immersing ground beef chub packs in a brine chiller (‐2°C). Hamburger patties were prepared from both hot and cold‐boned chub packed, coarse ground beef after 0, 7, 14, and 21 days of storage (0°C). Microbiological quality of the hot‐boned ground beef was either superior or equal to that of the control. Purge present in all the chub packs after 21 days of storage was 1.0%. Patties prepared from CO2 chilled ground beef were more tender than control patties. Patties prepared from brine‐chilled ground beef had greater cooking losses than patties prepared from cold‐boned ground beef.
Palatability of Beef Skirt Steaks as Influenced by Grade/Maturity Group, Anatomical Location and Mechanical Tenderization
Authors: RECIO H.A. , FRADELLA L.C. , CROSS H.R. , SMITH G.C. , SAVELL J.W.
Published: August 2006

Beef inside and outside skirts (n = 120) obtained from 30 U.S. Choice carcasses and from 30 U.S. Utility cow carcasses were used in a study to evaluate anatomical location, grade/maturity group and method of mechanical tenderization on the palatability of cooked “fajita” beef. Ratings for juiciness, muscle fiber tenderness, overall tenderness, and overall palatability were higher (P < 0.05) for outside skirts than for inside skirts. Skirt steaks—inside and outside—from U.S. Choice carcasses were juicier, more tender overall, and more palatable overall than skirt steaks from U.S. Utility carcasses. Cubing, as a method of tenderization, was more useful for skirts from U.S. Utility carcasses than for skirt steaks from U.S. Choice carcasses.
Liquid Loss in Shucked Oyster (Crassostrea virghica) Meats During Ice Storage
Authors: COOK D.W. , CHAI T. , HACKNEY C.R. , MARTIN R.E. , OTWELL W.S. , WARD D.R.
Published: August 2006

East and Gulf coast oysters were processed under Code of Federal Regulation (CFR) requirements, packed in retail size containers and stored on ice for 18 days. At 3‐day intervals, containers of oyster meats were tested for free liquid content. Gulf coast oyster meats lost more liquid and in a different pattern during storage than East coast oysters. Seasonal differences in liquid loss were noted in Gulf coast oysters only. Washing oyster meats by blowing in accordance with CFR requirements did not increase liquid loss during the first 9 to 12 days of storage. Liquid loss in Gulf coast oysters was inversely correlated with salt content. Except for oysters with low salt content, most containers of oyster meats did not exceed 15% free liquid during storage.
Chemical Properties of Cryocasein
Authors: MOON T.W. , PENG I.C. , LONERGAN D.A.
Published: August 2006

Some chemical properties of cryocasein were examined and compared to those of commercial casein and caseinates. Cryocasein contained more ash and lactose than commercial casein and caseinates. Compared to acid casein, cryocasein had slightly less β‐casein due to the preparation procedures involving low temperature and ultrafiltration. Retainment of micellar structure was verified by electron microscopy and permeation chromatography on CPG‐10. An increase in aggregation of casein miscelles was observed during frozen storage (−8°C) of diluted ultrafiltration retentate. Similar to the casein in skim milk, this intact micellar structure may be responsible for properties such as solvation and stability towards addition of ethanol and Ca2+.
Apple Quality as Influenced by Fumigation with Methyl Bromide
Authors: DRAKE S.R. , MOFFITT H.R. , FELLMAN J.K. , SELL C.R.
Published: August 2006

The use of methyl bromide (MeBr) did not detract from the firmness or skin color of‘Delicious’, ‘Golden Delicious’ or ‘Granny Smith’ apples. Fruit fumigation with MeBr resulted in a darkening of the objective and subjective internal flesh color of ‘Delicious apples, particularly unwaxed apples treated with 48g MeBr/m3 at 20°C for 2 hr. Internal flesh color of ‘Golden Delicious’ apples was not influenced at 48g MeBr/m3 at 6°C for 2 hr. Fumigation with 32g MeBr/ m3 at 20°C or 56g MeBr/m3 at 6°C for 2 hr did not detract from the firmness or internal color quality of ‘Delicious’, ‘Golden Delicious’ or ‘Granny Smith’ apples after 60 days in storage. MeBr‐treated apples displayed greater acidity and less ethylene production than control fruit. Higher MeBr treatment temperature and the use of wax on fruit directly influenced the reaction of apples to MeBr fumigation.
Ascorbic Acid/Citric Acid Combinations in the Processing of Frozen Apple Slices
Authors: SANTERRE CHARLES R. , CASH J.N. , VANNORMAN D.J.
Published: August 2006

Sulfite replacement was investigated in a commercial apple freezing operation: Jonathan and Spy apple slices were vacuum‐impregnated in 0.5% or 1% ascorbic acid (LAA) or D‐araboascorbic acid (DAA). 0.25% or 0.5% citric acid (CA), 2h NaCl, and 0.25% CaCl2 Treatments with DAA gave color and sensory properties equal to LAA treatments. Slice color was not significantly different between 0.5% and 1.0% ascorbic acid isomers and 0.25% or 0.5% CA. Shear measurements of Jonathan slices were significantly influenced by DAA and citric acid concentrations. Texture of Spy slices was not affected by treatment or storage. This study indicates that DAA may be substituted for more expensive LAA for treating Spy and Jonathan slices prior to freezing.
Indigenous Yeast Microflora on Arkansas White Riesling (Vitis vinifera) Grapes and in Model Must Systems
Authors: MOORE K.J. , JOHNSON M.G. , MORRIS J.R.
Published: August 2006

The indigenous yeast microflora on Arkansas‐grown White Riesling (Vitis vinifera) grapes and in model musts were examined during fermentation of sulfite‐treated (0, 25, 50, or 100 mg/L total SO2) musts held at two temperatures 113°C and 21°CL The yeast microflora were examined with time −13°C musts were sampled it 5, 10, and 20 days; 21°C musts were sampled at 2, 4, and 8 days. A two log cycle increase in yeast counts occurred during fermentation, with little difference in counts due to sulfite treatments. Of 70 isolates, the main genera were Cryptococcus, Hanseniaspora, Pichia, Saccharomycopsis, Trichosporon, Zygosaccharomyces, Rhodotorula, Candida, Metschnikowia, and Succharomyces. All isolates recovered showed lipolytic activity on Spirit Blue Agar.
Effect of Pre‐decortication Drying Treatment on the Textural Quality of Cowpea Products: Seeds and Akara
Authors: HUNG Y.‐C. , CHINNAN M. S. , McWATTERS K. H.
Published: August 2006

This study describes the influence of a pre‐decortication drying treatment on the textural quality of cowpea seeds and akara (fried cowpea paste). Heat‐treated seeds were more brittle than the unheated control, but there were no significant differences in seed brittleness among drying temperatures. Akara from the 110°C treatment was less cohesive and required more energy per unit mass to shear and compress than the other samples. Overall, the 50°. 70° and 90°C treatments produced akara that compared favorably in textural quality to the control. Objective textural parameters obtained from either TPA or the Kramer cell method correlated well with sensory measures of texture.
Functionality of Commercially Produced Wheat Flour Solubles in Cakes, Cookies, and Wieners
Authors: OOMAH B.D. , MATHIEU J.J.
Published: August 2006

The performance of wheat flour solubles (WFS) obtained by ultrafiltration and spray drying of a gluten‐wheat starch plant effluent was evaluated in cakes, cookies, and wieners. Batter density, cake volume, and quality of high ratio white layer cake decreased with increase in the level of WFS when it was used either as a wheat flour substitute (0–20%) or an egg white substitute (0–50%). Volume and textural characteristics of a yellow layer cake with and without substitution by WFS of 50% whole egg was not significantly different. Increasing WFS substitution levels (0–25%) of a sugar‐snap cookie formulation reduced the spread factor and increased the crispness of the cookies without significantly affecting other textural characteristics. Firmness and cook stability of wieners with (6% level) and without WFS were not significantly different.
Effective Thermal Conductivity of Granular Starch Materials
Authors: DROUZAS A.E. , SARAVACOS G.D.
Published: August 2006

The effective thermal conductivity (keff of two granular starches was investigated at various bulk densities, temperatures and moistures, using the method of heated probe. Granular powders of high‐amylose and high‐amylopectin starches were used at bulk densities 500‐800 kg/m3, temperatures 25–70°C. and moistures of 0–40%. The keff increased linearly with bulk density, from 0.065 to 0.220 W/mK. Temperature had a positive effect up to 6.5% moisture. At higher moistures keff increased sharply above 50°C, indicating starch‐water interaction. The keff increased linearly with moisture at low (0–15%) and high (> 25%) moistures, remaining nearly constant at intermediate moistures. These changes were related to the porosity of the starches.
Preparation and Functional Properties of Linseed Protein Products Containing Differing Levels of Mucilage
Authors: DEV D.K. , QUENSEL E.
Published: August 2006

The functionality of two high‐mucilage protein concentrates (HMPC) prepared from linseed and linseed expeller cake by extracting and coprecipitating the mucilage with protein was compared with those of a low‐mucilage flour (LMF), a protein concentrate (LMPC), and a protein isolate (LMPI) in simple systems. The HMPC samples had better water absorption and emulsifying properties, higher foaming capacity, but lower nitrogen solubility, oil absorption, and foam stability than LMF and LMPC. They also registered higher values of viscosity and emulsification characteristics than LMPI.
Antioxidant Effects of Protein‐Bound Riboflavin and Free Riboflavin
Authors: TOYOSAKI TOSHIYUKI , MINESHITA TAKESHI
Published: August 2006

We studied the antioxidant effects of protein‐bound riboflavin and free riboflavin using methyl linoleate in a water system in the dark. The protein‐bound riboflavin inhibited the formation of hydroperoxides. After exposure to light, the protein lost its antioxidant effect, which suggested that it was not the protein‐bound riboflavin but the riboflavin itself that had the antioxidant effect. These results showed that riboflavin inhibited the formation of hydroperoxides, which suggested that it did have an antioxidant effect.
Electron Paramagnetic Resonance Studies of the Effectiveness of Myoglobin and Its Derivatives as Photosensitizers in Singlet Oxygen Generation
Authors: WHANG K. , PENG I. C.
Published: August 2006

The effectiveness of myoglobin and its derivatives as photosensitizers in singlet oxygen (1O2) generation was determined by electron paramagnetic resonance (EPR) spectroscopy using a spin trapping technique. A stable nitroxide radical adduct, 2,2,6,6,‐tetramethyl‐4‐piperidone‐N‐oxyl (TAN), was formed and detected by EPR. Native myoglobin and apomyoglobin exhibited no photosensitizing function, whereas hematin appeared to be a weak sensitizer. Protoporphyrin IX ring showed strong photosensitizing activity. A 1O2 quencher, N,N N′N′‐tetramethylethylene diamine (TMEDA) and the combination of TMEDA and a free radical scavenger, butylated hydroxyanisole (BHA) drastically reduced the EPR signal of TAN when protoporphyrin IX solution was illuminated indicating that 1O2 was produced using protoporphyrin IX ring as a sensitizer.
A Kinetic Approach to Food Quality Prediction Using Full‐History Time‐Temperature Indicators
Authors: WELLS JOHN HENRY , SINGH R. PAUL
Published: August 2006

A mathematical model based on the theory of chemical kinetics was derived to predict food quality change from the response of a full‐history time‐temperature indicator. A first‐order kinetic reaction (n = 1) was used to describe both indicator response and changes in food quality. A storage investigation of mature green tomatoes showed that the quality prediction model satisfactorily predicted changes in tomato firmness induced by variable temperature storage. Tomato firmness as predicted from the response of a LifeLines model 57 time‐temperature indicator was not significantly different from the observed changes (F = 1.99, p = 0.18) for 28 days of storage. The mathematical derivation was extended to develop a quality‐based interpretation of the shelf life of perishable foods.
Thermal Processing Retortable Plastic Containers with Metal Lids in Steam and Water with Comparisons to Metal Cans
Authors: BERRY MAURICE R. , BUSH RALPH C.
Published: August 2006

Comparative heating studies were conducted for three products in 211 × 214 retortable plastic containers with double‐seamed metal lids and in similar sized 211 × 300 metal cans. Plastic cans heated slower than metal cans in both steam and water. Orientation of the metal lid (up or down) influenced heating and the location of the slowest‐heating zone. For corn in brine heated in steam, Fo values for the heating portion of the process were 6.5, 4.2, and 5.0 using the metal can, and the plastic cans oriented with lid up and lid down, respectively. Similar differences were obtained for cans of water and a conduction‐heating product. The heating medium and headspace in the container only slightly influenced the Fo value delivered by the thermal process.
Effect of Rapid Chilling and Accelerated Processing on the Physical and Sensory Characteristics of Cured Pork Bellies
Authors: NEEL S. W. , REAGAN J. O. , MABRY J. W. , MILLER M. F.
Published: August 2006

The effects of accelerated and conventional processing systems on the physical and sensory characteristics of cured pork bellies were investigated using three accelerated processing systems. Accelerated processing, with or without electrical stimulation, was effective in producing bellies and bacon strips equal to or superior to those which were conventionally processed. Non stimulated accelerated processing samples were evaluated as being less crispy than other treatments. Rapid chilling in conjunction with accelerated processing, with or without the aid of electrical stimulation, can produce cured bellies as well as bacon slices that are comparable in all traits with bellies from conventionally processed carcasses.
Mutagenic Activity of Heat‐Induced Cholesterol‐Degradation Products
Authors: WATANABE K. , NAKAMURA R. , HOSONO A.
Published: August 2006

Mutagenic activities of degradation products from pure crystalline cholesterol by heat‐treatment in air were examined with a streptomycin‐dependent strain from the Salmonella typhimurium TA98. Heatings at 225°C for periods of over 5 hr or at temperatures above 150°C for 7 hr were required for mutagens to be detected.
Comparison of Methods for Quantitation of Free Fatty Acids in Cheese
Authors: IKINS W.G. , KWAK H.S. , ZINK G.S. , JEON I.J.
Published: August 2006

A comparison of three relatively rapid methods of determining free fatty acids concentrations in cheese was performed by correlating the results with a more laborious but accurate gas chromatographic (GC) technique. Acid Degree Values were found to correlate poorly with the GC data, particularly for short chain fatty acids. Values obtained using a Copper Soap Method correlated closely with the GC data for total and long chain fatty acids, but did not correlate as well with short chain fatty acids levels. The Extraction‐Titration Method was found to be a simple and reliable technique that yielded values which correlate closely with short chain fatty acid concentrations.
Detection of Singlet Oxygen Generation by Chlorophyll using Electron Paramagnetic Resonance Spectroscopy
Authors: WHANG K. , PENG I. C.
Published: August 2006

Electron paramagnetic resonance (EPR) spectroscopy was used to detect the photosensitized generation of singlet oxygen (1O2) by chlorophyll b. Illumination of a chlorophyll b solution containing a spin trap (2,2,6,6‐tetramethyl‐4‐piperidone, TMPD) yielded pronounced EPR signals for TAN (2,2,6,6‐tetramethyl‐4‐piperidone‐N‐oxyl) suggesting the presence of 1O2. N,N,N′,N′‐tetramethylethylene diamine (TMEDA, a 1O2quencher) and a combination of TMEDA with a free radical scavenger (butylated hydroxyanisole, BHA) completely eliminated the TAN signal. BHA alone did not exert this inhibitory effect.
Heat‐Induced Textural and Histological Changes of Ordinary and Dark Muscles of Yellowfin Tuna
Authors: KANOH SATOSHI , POLO JOSE MIGUEL ALEMAN , KARIYA YUTAKA , KANEKO TOYOJI , WATABE SHUGO , HASHIMOTO KANEHISA
Published: August 2006

When a fresh specimen of yellowfin tuna Neothunnus albacora was analyzed, the cross‐sectional area of ordinary (white) muscle fiber was 3.5 times larger than that of dark muscle. As heating temperature was raised, the shear force of dark muscle became progressively larger than that of ordinary muscle. Simultaneously, the A band in the ultrastructure of both muscles was stained more densely. While the Z line in I band of dark muscle still remained, that of ordinary muscle disappeared completely by heat treatment at 60°C for 30 min. Therefore, the differences in toughness change during heat treatment correlated well with that fiber sizes and ultrastructures of the two types of muscle.
Preparation of Transparent Egg White Gel with Salt by Two‐step Heating Method
Authors: KITABATAKE NAOFUMI , SHIMIZU ATSUSHI , DOI ETSUSHIRO
Published: August 2006

A heat‐induced transparent gel from egg white was prepared at low pH and low ionic strength by a one‐step heating method. The addition of NaCl to the egg white formed a turbid gel on heating. Egg white, first diluted with water, gave a transparent solution upon heating of this mixture. The solution formed a transparent gel when heated with NaCl up to a concentration of 0.3M for a second time. The transparent gel obtained at 150 mM NaCl was more firm and less adhesive than the turbid gel prepared by the one‐step heating method at the same pH, protein concentration, and NaCl concentration.
Methionine Enrichment of Milk Protein by Enzymatic Peptide Modification
Authors: HAJÓS GY. , ÉLIÁS I. , HALÁSZ A.
Published: August 2006

Methionine‐enriched protein was produced from an enzymatically pre‐hydrolyzed milk protein using an enzymatic peptide modification (EPM) method with α‐chymotrypsin as catalyst. Methionine of the product was twice as high as that of the substrate protein. The incorporated methionine formed a covalent bond with the peptide chain in the product protein. The change in the number of peptide bonds was monitored by the degree of hydrolysis (DH). The slight change of the DH values revealed that a portion of the free amino acids was bound to the peptide chains during the reaction and that transpeptidation was the main process during the EPM treatment. The location of the newly incorporated amino acids was determined by identification of the terminal amino acids. The covalently bound methionine was located in C‐ and N‐terminal positions in a ratio of 3:1.
Inhibition of Mushroom Polyphenoloxidase by Ascorbic Acid Derivatives
Authors: HSU A.F. , SHIEH J.J. , BILLS D.D. , WHITE K.
Published: August 2006

Ascorbic acid (AA), dehydroascorbic acid (dehydroAA), isoascorbic acid (isoAA), ascorbic acid‐2‐phosphate (AA‐2‐ PO4), and ascorbic acid‐2‐sulfate (AA‐2‐SO4) were tested as inhibitors of mushroom polyphenoloxidase (PPO). Kinetic analysis indicated that AA and isoAA were more effective than dehydroAA. The half times (t1/2) that decreased 50% of PPO activity for AA, isoAA and dehydroAA were 2.5, 3.1, and 1.9 hr, respectively, and the concentrations that inhibited half of PPO activity were as follows: ascorbic acid, 0.04 mM, isoAA, 0.25 mM; and dehydroAA, 7.5 mM. Electron spin resonance studies demonstrated that the Cu2+ of PPO was reduced to Cu+ by AA. AA‐2‐PO4 and AA‐2‐SO4 were not inhibitors for PPO. However, the digestion of AA‐2‐PO4 with acid phosphatase yielded AA to inhibit PPO activity. AA‐2‐SO4 was found to be a poor substrate for sulfatase.
Effects of Enzyme Modified Soy Protein on Rennet‐Induced Reconstituted Nonfat Dry Milk Coagulum Properties
Authors: MOHAMED M.O. , MORRIS H.A.
Published: August 2006

Soy protein was hydrolyzed by trypsin, pepsin and α‐chymotrypsin. Effects of adding hydrolyzed soy protein on rennet‐induced nonfat milk coagulum texture and syneresis were studied. Pepsin‐modified soy protein increased coagulum firmness and syneresis greater than untreated soy protein. Soy protein hydrolyzed with trypsin for 150 min and added to nonfat milk increased coagulum firmness greater than nonfat milk with no soy protein added. Chymotrypsin‐modified soy protein acted similarly to the trypsin modified soy protein except the coagulum firmness was less than nonfat milk alone. Soy protein hydrolyzed by trypsin followed by pepsin increased coagulum firmness more than hydrolysis by a single enzyme and was close to nonfat milk without soy protein.
Isolation and Characterization of Pectin in Sugar‐Beet Pulp
Authors: PHATAK L. , CHANG K.C. , BROWN G.
Published: August 2006

Pectin was extracted from sugar‐beet pulp by various solvent fractionation procedures. An optimal HCI‐extraction method yielded 19.53% pectin from the raw material. The HCl‐isolated pectin contained 81.8% galacturonic acid. The sugar‐beet pulp pectin obtained from different extraction procedures had a high methoxy content ( 60% degree of methylation). The pectin also contained 10 to 17.5% neutral sugars which were mainly arabinose and galactose as analyzed by gas chromatography. The peak molecular weights (relative to dextrans) of the pectins as determined by gel permeation ranged from 35,500 to 44,700 daltons. The pectin possessed high water‐holding capacity and low viscosity.
Influence of the Enzymatic Modification of the Nonstarchy Polysaccharide Fractions on the Baking Properties of Reconstituted Rye Flour
Authors: KÜHN M. C. , GROSCH W.
Published: August 2006

The effect of the nonstarchy polysaccharide (NSP)‐hydrolases on the properties of rye bread was established by enzymatic modification of the enriched soluble and insoluble NSP fractions, followed by flour recombination and bread baking (20g flour per minibread). Two microbial enzyme preparations were used for the modification (incubation 2 hr at 28°C, 15 min at 75°C, and 10 min at 95°C; pH 4.6). Modification of the insoluble NSP decreased crumb firmness and increased specific volume. Hydrolysis of the soluble NSP decreased the specific volume. Treatment of both fractions improved crumb structure, decreased crumb firmness and increased the width/height ratio of the minibreads.
Barley Flour Level and Salt Level Selection for a Whole‐grain Bread Formula
Authors: SWANSON RUTHANN B. , PENFIELD MARJORIE P.
Published: August 2006

Thual hull‐less barley from Alaska and Tennessee was ground into whole‐grain flours (10.5 and 14.4% protein, respectively). A potentially feasible bread formula was identified from response surfaces depicting effects of barley and salt levels within barley source on dough development parameters. Breads containing 20% barley, 30% whole‐wheat and 50% bread flours and 2.0% salt were prepared from each flour; a control contained 50:50 whole‐wheat:bread flour with 2% salt. Barley decreased specific loaf volume 5–6%. Instron hardness, cohesiveness, springiness, and chewiness were similar; lower protein barley bread was more gummy than the control. Overall flavor, appearance, and texture acceptability did not differ. Barley bread as prepared was feasible, suggesting the usefulness of response surfaces in formula development.
Iron Binding by Ovotransferrin from Ferric Nitrilotriacetate at pH 5 and pH 5.5
Authors: THOMPSON DONALD B.
Published: August 2006

Binding of iron to ovotransferrin (OTf) in egg white at low pH was studied. At pH 5 iron as ferric nitrilotriacetate (FeNTA) bound to only 25% of the OTf iron‐binding sites. Although this binding caused a 1°C increase in OTf denaturation temperature, enthalpy of denaturation apparently decreased. At pH 5.5, the apo‐OTf denaturation temperature was about 4°C higher than at pH 5. FeNTA bound to 40% of the OTf iron‐binding sites; again a small increase in denaturation temperature and an apparent decrease in enthalpy was observed. Work with purified OTf suggests that the denaturation enthalpy decrease observed in egg white may be due to overlapping of the OTf and albumin endotherms.
Sensory Evaluation of Rancidity and Off‐Flavor in Frozen Stored Meat Loaves Fortified with Blood
Authors: OELLINGRATH INGER M. , SLINDE ERIK
Published: August 2006

Meat loaves with 0–5% blood added were stored at ‐ 20°C for 1 yr and evaluated for rancidity and off‐flavor by a descriptive sensory panel. Significantly higher rancidity and off‐flavor values were observed in meat loaves with 1% and 2% blood than in products with no blood added. When 3 to 5% blood was added, the calculated molar ratio of polyunsaturated fatty acids (PUFA) to heme was in the region where heme compounds have been observed to act as antioxidant, and no further increase in rancidity or off‐flavor was observed.