bluuebunny/crossref_metadata_2025 huggingface dataset:
Strawberry Polyphenoloxidase: Purification and Characterization
Authors: WESCHE‐EBELING PEDRO , MONTGOMERY MORRIS W.
Published: August 2006

Stable and highly active polyphenoloxidase (PPO) extracts were obtained using polyvinylpyrrolidone, Amberlite XAD‐4, Triton X‐100, and protease inhibitor in pH 5.25 buffer. Citrate and phosphate prevented binding of PPO to pectin. Phenyl sepharose chromatography resolved PPO into two isozymes (PPO‐F1 and PPO‐F2) both separated from pectin. PPO‐F1 had a molecular weight of 111,000, did not penetrate the running gel during electrophoresis, and was bound by concanavalin suggesting that it contained carbohydrate. PPO‐F2 resolved into two peaks during DEAE‐chromatography, had a molecular weight of 34,500, and resolved into two bands during electrophoresis.
Physical Properties as Indicators of Popping Characteristics of Microwave Popcorn
Authors: PORDESIMO L.O. , ANANTHESWARAN R.C. , FLEISCHMANN A.M. , LIN Y.E. , HANNA M.A.
Published: August 2006

Nondestructive physical property measurements, such as kernel size, sphericity, specific gravity and elastic deformation were evaluated as indicators of the popping characteristics of microwave popcorn. A greater expansion volume was observed in varieties having sphericity values greater than 0.70. Within a given variety, larger kernel sizes resulted in a lower unpopped kernel ratio and the expansion volume and flake size were higher for kernels with a higher specific gravity. The elastic deformation was found to have no correlation with microwave popping.
Gelatinization and Liquefaction of Starch with a Heat Stable α‐Amylase
Authors: LEE Y.C. , KIM K.T.
Published: August 2006

Sweet potato and corn starches were gelatinized and liquefied to dextrose equivalent (DE) 10 in a steam‐jacketed kettle or in a twin‐screw extrusion cooker in a single step process with a heat stable ex‐amylase. The time required to gelatinize and liquefy 20% starch slurries in a kettle at 95°C was 45 to 50 sec. Starch powder (10 kg/hr) and water (2‐6 kg/hr) were fed to an extrusion cooker to adjust the moisture contents of the starch from 20 to 55% (wet basis) and gelatinized and liquefied to DE 10 at a barrel temperature of 120°C or above with 2 to 3% (w/w) a‐amylase added. The optimum conditions for the operation were to feed starch with water to maintain 50% moisture and 2% heat stable a‐amylase at a barrel temperature of 120°C.
Drying, Packaging, and Storage Effects on Quality of Basil, Marjoram and Wild Marjoram
Authors: PÄÄKKÖNEN K. , MALMSTEN T. , HYVÖNEN L.
Published: August 2006

Sorption isotherms, color and sensory qualities of basil (Ocimum basilicum L.) and marjoram (Origanum majorana L.) and sensory qualities of wild marjoram (Origanum vulgare L.) were used to determine effects of packaging, storage temperature and time on air‐dried and freeze‐dried herbs. Sorption isotherms showed herbs dried with different methods exhibited different sorption capacities. Both odor and taste of freeze‐dried basil and the freeze‐dried and air‐dried marjorams were very sensitive to storage conditions. Processing and storage conditions had only moderate effects on flavor of wild marjoram. The study demonstrated that quality of dried basil, marjoram and wild marjoram could be maintained for 2 yr in air‐tight packages at room temperature.
Methodology to Determine Destruction of Bacterial Spores during Extrusion Cooking
Authors: LIKIMANI T.A. , SOFOS J.N. , MAGA J.A. , HARPER J.M.
Published: August 2006

A methodology was developed for determining destruction of bacterial spores during extrusion cooking in a single screw extruder. Procedures were developed for estimating processing time at different screw speeds and calculation of “D‐” and “z‐values.” The proposed methodology evaluated destruction of Bacillus globigii spores in 18% moisture corn/ soybean mixture (70/30%, w/w). “D‐value” expressed on the basis of average time at mass temperature >95°C during extrusion was the most conservative estimate of spore sensitivity. Times ranged from 1.7 sec at 115°C to 6.6 sec at 100°C maximum mass temperatures. These “D‐values” resulted in a “z‐value” of 25.3°C., similar to that reported for the same strain with dry heat.
Browning of Dehydroascorbic Acid and Chlorogenic Acid as a Function of Water Activity
Authors: MONSALVE G. ADELMO , POWERS JOSEPH R. , LEUNG HENRY K.
Published: August 2006

Browning and degradation of dehydroascorbic acid (DHA) and chlorogenic acid (CA) at pH 6, was studied at variable water activities (aw) and temperature in a model food system containing cellulose, DHA and/or CA. Rate of DHA browning followed an apparent zero order reaction and was maximum at intermediate aw. Activation energies for browning ranged from 13‐17 Kcal and were independent of aw. Browning and degradation of CA was negligible at aw below 0.6. CA loss in the DHA‐CA mixture was apparently delayed by decomposition products of DHA and this was pronounced at high aw.
Purification of Steviosides by Membrane and Ion Exchange Processes
Authors: FUH WEA‐SHANG , CHIANG BEEN‐HUANG
Published: August 2006

An ultrafiltration (UF) process removed more than 96% of the pigments and recovered 45% of steviosides non‐nutritive sweetener from an extract of leaves. UF retentate was further processed by diafiltration (DF), and the permeate was concentrated by reverse osmosis (RO). The membrane processes (UF, DF, RO) achieved an overall steviosides recovery of more than 90% with product purity 46%. Final purification was conducted by two consecutive mixed bed ion exchange processes. The ion exchangers improved purity of the final product to 90%.
Total Polyphenols in Apples and Ciders; Correlation with Chlorogenic Acid
Authors: CILLIERS J.J.L. , SINGLETON V.L. , LAMUELA‐RAVENTOS R.M.
Published: August 2006

The chlorogenic and caffeic acid combined in apple juice cultivars and ciders correlated very well with total phenol content (P 0.001; r = 0.989; n = 22). The same correlation was found when analyzed strictly by cultivar (P 0.001; r = 0.986; n = 10). Analysis used automated Folin Ciocalteu (FC) colorimetry values for total phenols and reversed‐phase HPLC (280 nm detection) for chlorogenic and caffeic acid before and after fermentation. Concentrations were between 8 and 1012 mg/L (as chlorogenic acid) in different cultivars. The total chlorogenic acid by HPLC represented only 6.2 to 10.7% of the total polyphenol (calculated as chlorogenic acid) by FC in the apple cultivars for all samples. Total peak areas correlated very well with total phenol content by FC (P 0.001; r = 0.994; n = 22).
Identification and Quantification of the “Popcorn”‐like Aroma in Louisiana Aromatic Delia Rice (Oryza sativa, L.)
Authors: LIN CHARLES F. , HSIEH THOMAS C.‐Y. , HOFF BERT J.
Published: August 2006

The “popcorn” like aroma was identified as 2‐acetyl‐l‐pyrroline. Cooked Delia white rice contained almost 300 ng 2‐acetyl‐1‐pyrroline per g (dry weight) rice, while cooked Lemont white rice (nonaromatic cultivar) contained 4 ng per g (dry weight). Delia white rice contained almost four times more 2‐acetyl‐l‐pyrroline as the average (73 ppb) in two batches of Jasmine white rice imported from Thailand and comparably analyzed.
Two Methods for Determining Extract Release Volume (ERV) of Fresh and Spoiled Beef and Poultry Meats
Authors: JAY JAMES M. , HOLLINGSHED ANDREA M.
Published: August 2006

When the ERV of ground and diced beef that underwent microbial spoilage at 5°C was determined in the conventional way by use of Waring Blendor and by use of Stomacher 400 (Tekmar Co., Cincinnati, OH), comparable values were obtained. However, for ground or diced chicken meat, Stomacher values were consistently higher than those when using the Blendor. The basis for differences between the two methods for chicken meat is unclear.
Sensory and Chemical Characteristics of Fresh Pork Roasts Cooked to Different Endpoint Temperatures
Authors: HEYMANN H. , HEDRICK H.B. , KARRASCH M.A. , EGGEMAN M.K. , ELLERSIECK M.R.
Published: August 2006

Pork roasts cooked to various endpoint temperatures were evaluated by sensory and chemical analyses. Increased endpoint temperatures were associated with increased cooking losses; decreased juiciness, pink color, and metallic flavor; increased graininess, brown color, and pork flavor. Increased endpoint temperatures also led to a concentration of lipid, protein and certain fatty acids. Cholesterol levels were not significantly influenced by endpoint temperature. Lipid content was decreased by removal of external fat before cooking. To minimize pink color in some muscles and maximize other sensory characteristics and yield of cooked meat, at least 71.1°C and no more than 76.6°C is recommended as the endpoint temperature for fresh pork roasts.
Acceptability of Bacon as influenced by the Feeding of Elevated Levels of Monounsaturated Fats to Growing‐finishing Swine
Authors: SHACKELFORD S.D. , MILLER M.F. , HAYDON K.D. , LOVEGREN N.V. , LYON C.E. , REAGAN J.O.
Published: August 2006

The acceptibility of bacon produced from swine fed diets containing elevated levels of oleic acid was evaluated. Slicing yields and sensory scores for overall palatability and flavor quality were lower for bacon produced from swine fed canola oil (P < 0.05). A higher percentage of panelists detected off‐flavors in canola oil bacon than in bacon produced from swine fed safflower oil, sunflower oil, animal fat or a typical corn‐soybean meal diet (P < 0.05).
Antibiotic Residues and Drug Resistant Bacteria in Beef, and Chicken Tissues
Authors: VÁZQUEZ‐MORENO L , BERMÚDEZ A. M.C. , LANGURÉ A. , HIGUERA‐CIAPARA I. , DE AGUAYO M. DÍAZ , FLORES E.
Published: August 2006

Chicken and bovine tissues from Hermosillo, Mexico, were analyzed for penicillin, tetracycline, streptomycin, chloramphenicol and gentamycin presence and concentration using a biological radio‐assay (Charm Test II). The samples were also analyzed for antiobiotic resistant bacteria. The concentrations found varied widely for each antibiotic family and were above FDA tolerance limits. Penicillin was not detected in the samples. Almost 50% of beef tissues presented two different antiobiotics, while three were commonly found in chicken. E. coli, S. epidermidis, H. alvei, E. agglomerans, P. mirabilis, Salmonella sp., Citrobacter, E. aerogenes; and S. aureus were among the most commonly found microorganisms. They mainly presented antibiotic resistance to penicillin, tetracycline and streptomycin.
Meat By‐product Protein Composition and Functional Properties in Model Systems
Authors: NUCKLES R.O. , SMITH D.M. , MERKEL R.A.
Published: August 2006

Composition and functional properties of selected meat by‐products were studied. Mechanically deboned chicken meat (MDCM) and meat by‐products (pork lung lobes, pork liver, beef lung lobes, beef spleen, beef heart) varied in their proximate composition, amount of the three major protein fractions [low ionic strength soluble (LIS), high ionic strength soluble (HIS), insoluble] and collagen content. Cooked batter model system reheat yield was positively correlated with the quantity of HIS proteins and the percentage myosin and actin in the HIS protein fraction. Stress and strain at failure of the cooked batters were inversely correlated to the amount of LIS proteins and positively correlated with the percentage of myosin and actin in the by‐products.
Evaluations of Warmed‐over Flavor during Chill Storage of Cooked Broiler Breast, Thigh and Skin by Chemical, Instrumental and Sensory Methods
Authors: ANG C. Y. W. , LYON B. G.
Published: August 2006

Broiler breast, thigh and skin were cooked to 80°C, stored at 2°C for up to 5 days, and evaluated by chemical, gas chromatographic (GC) and sensory methods. Water and fat content of cooked meat did not change during storage. Thiobarbituric acid (TBA) values and levels of major headspace volatiles increased throughout storage time. Intensities of cardboard, warmed‐over, rancid/painty, and overall off‐flavor characteristics increased. Skin showed the least changes. Breast and thigh meat differed in GC profiles but were similar in sensory scores after 1 day and in TBA values after 2 days of storage. Both TBA and headspace GC measurements are associated with the off‐flavor development.
Headspace Volatiles and Sensory Characteristics of Ground Beef from Forage‐ and Grain‐Fed Heifers
Authors: LARICK D.K. , TURNER B.E.
Published: August 2006

Twenty‐seven yearling Hereford‐Angus heifers were allotted to one of three intense managed pasture systems: Tifleaf pearl millet, sorghum sudangrass and fescue‐clover. After grazing, heifers were finished in drylot and then serially slaughtered at 0, 52, and 82 days in the feedlot (DIF). A total of 51 volatiles were identified in ground beef from Longissimus dorsi (L. dorsi) muscle and subcutaneous fat. Major classes of volatile compounds identified included hydrocarbons and aldehydes plus fewer numbers of ketones, alcohols, aromatic compounds and sulfur‐containing compounds. The majority of compounds which varied due to DIF were alkanals and alk‐2‐enals. The concentration of each of the volatiles which varied due to DIF was found to increase. None of the volatiles quantitated were positively correlated with sweetness or gamey aftertaste, the two characteristics which were highest for the O DIF cattle.
Inhibition of Modori (Gel Weakening) in Surimi by Plasma Hydrolysate and Egg White
Authors: HAMANN D.D. , AMATO P.M. , WU M.C. , FOEGEDING E.A.
Published: August 2006

The effects of beef plasma hydrolysate and egg white solids were evaluated in surimi gels using measurements of torsional shear stress and strain, bound water, cook loss and SDS‐PAGE. Treatments included level of protein addition, surimi type (by species and grade) and cooking schedule. Addition of proteins, regardless of type or level of addition, significantly increased torsional shear stress and strain for all gels precooked at 60°C (90°C final cook). For gels made from low quality surimi, all levels of treatment proteins improved stress and strain for all cooking schedules and improved water holding for gels precooked at 60°C. Electrophoretic results showed a decrease in the density of the myosin heavy chain only in those gels without added proteins precooked at 60°C.
Acceleration of Physicochemical Change in Carp Muscle by Washing in Either Chilled or Heated Water
Authors: WATABE SHUGO , HWANG GYU‐CHUL , USHIO HIDEKI , HATAE KEIKO , YAMANAKA HIDEAKI , HASHIMOTO KANEHISA
Published: August 2006

“Arai” (washing) is a traditional cooking method of fish preparation in Japan. Carp muscle slices were washed in water (49°C for 15 sec, or 0°C for 10 min), and examined for physical and biochemical changes. At 49°C, rigor‐mortis was accelerated, resulting in a marked decrease of muscle slice thickness. ATP degradation proceeded faster at 49°C than at 0°C. Arai treatment at 49°C increased myofibrillar Mg2+ ‐ AT‐Pase activity 8‐9 times in the absence of Ca2+, but did not affect activity in the presence of Ca2+ as much, giving only a 1.2 times increase.
Effect of Water Activity of Milk upon Growth and Acid Production by Mixed Cultures of Streptococcus thermophilus and Lactobacillus bulgaricus
Authors: LARSEN RAÜL F. , AÑÓN MARIA CRISTINA
Published: August 2006

Acid production and growth rates were determined in pure cultures of Streptococcus thermophilus and Lactobacillus bulgaricus and cocci/ bacilli ratios in mixed cultures of both species, using milk with modified aw as culture medium. Maximal growth rates were always at aw lower than 0.992 for all strains whcn aw of milk was adjusted with glycerol, while maximal acid production rates were at aw 0.992‐0.983. Glucose had an inhibitory effect additional to that caused by lowering aw. The cocci/bacilli ratio in mixed cultures increased as aw decreased in most cases, because of the higher susceptibility of L. bulgaricus to aw decrease. The behavior of a mixed culture could not always be predicted from data of the component strains in a pure culture, showing some kind of symbiotic compatibility between species.
Lipophilization of β‐lactoglobulin: Effect on Hydrophobicity, Conformation and Surface Functional Properties
Authors: AKITA E. M. , NAKAI S.
Published: August 2006

β‐Lactoglobulin was chemically modified by attaching different levels of stearic acid, and the effect on hydrophobicity, emulsifying and foaming properties was investigated. Incorporation of the hydrophobic ligands led to increased hydrophobic interactions, resulting in a decreasing solubility with extent of incorporation. Surface hydrophobicity measurements showed that the two fluorescence probes 8‐anilinonaphthalene‐1‐sulfonate (ANS) and cis‐parinaric acid (CPA) used were not equivalent. Some improvement of emulsifying and foaming properties was observed at low and medium levels of incorporation which decreased as the extent of fatty acid attachment further increased. High solubility and ANS surface hydrophobicity were both needed for the best emulsifying properties.
Composition of Apricot Aroma: Correlations between Sensory and Instrumental Data
Authors: GUICHARD ELISABETH , SCHLICH PASCAL , ISSANCHOU SYLVIE
Published: August 2006

Volatile compounds of six apricot cultivars were isolated by vacuum distillation and separated by gas‐chromatography. Eleven aromatic compounds were selected by sniffing and quantified after addition of known amounts of pure compounds. Sensory analyses were performed to rate the typicality of apricot aroma in these cultivars. Since the chemical extracts were not assessed significantly different from the raw product, statistical analyses were performed to correlate the typical sensory notes with the instrumental data. A correspondence analysis showed that cultivars could be separated into three clusters, according to their typical aroma. Hexyl acetate, γ‐octalactone and γ‐decalactone were shown to be key compounds for the apricot flavor whereas benzaldehyde could have a negative impact on the aroma of the less aromatic cultivars but would favorably complete the typical aroma of “Rouge du Roussillon.”
Survival and Growth of Listeria monocytogenes on Lettuce as Influenced by Shredding, Chlorine Treatment, Modified Atmosphere Packaging and Temperature
Authors: BEUCHAT LARRY R. , BRACKETT ROBERT E.
Published: August 2006

The effects of shredding, chlorine treatment and modified atmosphere packaging on survival and growth of Listeria monocytogenes, mesophilic aerobes, psychrotrophs and yeasts and molds on lettuce stored at 5°C and 10°C were determined. With the exception of shredded lettuce which had not been chlorine treated, no significant changes in populations of L. monocytogenes were detected during the first 8 days of incubation at 5°C; significant increases occurred between 8 and 15 days. Significant increases occurred within 3 days when lettuce was stored at 10°C; after 10 days, populations reached 108‐109 CFU/g. Chlorine treatment, modified atmosphere (3% O2, 97% N2) and shredding did not influence growth of L. monocytogenes. It was concluded that L. monocytogenes is capable of growing on lettuce subjected to commonly used packaging and distribution procedures used in the food industry.
Influence of Denaturation, Hydrophobicity and Sulfhydryl Content on Solubility and Water Absorbing Capacity of Soy Protein Isolates
Authors: WAGNER J.R. , AÑON M.C.
Published: August 2006

Solubility and water absorbing capacity of commercial soy protein isolates were correlated with structural parameters. The physico‐chemical properties studied were degree of protein denaturation, surface hydrophobicity and sulfhydryl groups. The results indicated that solubility and water absorption were affected differently as the parameters were varied. These functional properties depended on more than one structural parameter. Solubility in 0.2M NaCl solution provided information about the degree of denaturation of soybean protein isolates. Isolates with highly denatured proteins, high surface hydrophobicity, low solubility in 0.2M NaCl solution and low SH exhibited the highest water absorbing capacity.
Alteration of Talaromyces flavus Heat Resistance by Growth Conditions and Heating Medium Composition
Authors: KING A. DOUGLAS , WHITEHAND LINDA C.
Published: August 2006

A strain of Talaromyces flavus var. macrosporus (NRRL 13641) was isolated from spoiled fruit drink and identified. It had a heat resistance (l/k) (death rate constant or decimal reduction time) of 191 min at 80°C and 6 min at 90°C with a calculated z of 6.7°C. Several strains of T. flavus were tested to determine the effects on heat resistance of environmental conditions such as pH, organic acids, brix, and type of medium. Heat resistance increased with increased brix in the heating medium. Growth on solid medium compared with liquid medium resulted in greater heat resistance. Growth at 20°C and 35°C produced ascospores with higher heat resistance than growth at 25°C while those produced at 30°C had intermediate heat resistance. Five cultures differed significantly in heat resistance.
A Multi‐parameter Approach to Control the Growth of Saccharomyces cerevisiae in Laboratory Media
Authors: CERRUTTI PATRICIA , ALZAMORA STELLA M. , CHIRIFE JORGE
Published: August 2006

The effects of combinations of reduced water activity (aw from 0.97 to 0.93), pH (3, 4, 5, and 6) and addition of potassium sorbate (0, 100, 500, and 1,000 ppm) on the growth of one strain of Saccharomyces cerevisiae in laboratory medium were studied. The minimal aw for growth inhibition in the absence of sorbate and in the range of optimal pH was 0.89. Various combinations of aw, pH and sorbate concentration prevented growth of the yeast at aw values above 0.89. For example, at v = 0.93, addition of 100 ppm sorbate at pH = 4.0 resulted in inhibition; at aw= 0.97 and same pH (4.0), 500 ppm of sorbate were necessary. The combined effects of the above parameters on generation time, maximum population, and lag time of the cells were also determined.
Generating Kinetic Data for Use in Design and Evaluation of High Temperature Food Processing Systems
Authors: SADEGHI F. , SWARTZEL K. R.
Published: August 2006

The kinetics of sucrose (pH 2.5), Blue#2 (pH 11.3) and Blue#2 (pH 9.5) were determined for high food processing temperatures. A traditional batch kinetic data generation and a novel continuous flow method were examined. The novel method consisted of a tubular flow reactor designed to establish the time‐temperature equivalent points for any process. Activation energy values determined for the continuous method were 46.0, 27.2 and 52.3 kJ/mol for sucrose, Blue#2 (pH 11.3) and Blue#2 (pH 9.5), respectively. Values utilizing the traditional batch (capillary tube) generation method yielded 94.6, 58.2 and 74.5 kJ/mol, respectively. Based on these results, a new thermal evaluation technique is proposed for describing difficult to define continuous flow systems.
Shelf‐Life Enhancement of Lamb Meat under Refrigeration by Gamma Irradiation
Authors: PAUL PUSHPA , VENUGOPAL V. , NAIR P.M.
Published: August 2006

Influence of low dose gamma irradiation on the storage stability of fresh lamb meat (prepacked chunks and mince) at 0‐3°C was examined by sensory, microbiological and chemical criteria. The meat chunks irradiated at 1.0 kGy and 2.5 kGy remained in acceptable condition for 3 and 5 weeks respectively, whereas the corresponding shelf life for irradiated (1.0 kGy and 2.5 kGy) mince were 2 and 4 weeks respectively. In contrast, unirradiated meat chunks and mince spoiled within one week of storage at 0‐3°C.
Detection of Chemiluminescence Produced during Beer Oxidation
Authors: KANEDA HIROTAKA , KANO YUKINOBU , KAMIMURA MINORU , OSAWA TOSHIHIKO , KAWAKISHI SHUNRO
Published: August 2006

Chemiluminescence (CL) produced in beer was detected using the single photoelectron counting system. CL production did not occur in a nitrogen atmosphere but did occur in air and was dependent on incubation temperatures. It was inhibited by the addition of ascorbic acid. CL analysis should provide useful information in the study of oxidative deterioration of beer.
Effect of Germination and Fermentation on in vitro Starch and Protein Digestibility of Pearl Millet
Authors: KHETARPAUL NEELAM , CHAUHAN B.M.
Published: August 2006

Germination of pearl millet grain for 24 hr significantly improved itsin vitrostarch and protein digestibility. Fermentation of pearl millet sprouts by mixed culture combinations of yeasts and bacteria (Saccharomyces diastaticusandLactobacillus brevis; Saccharomyces diastaticusandLactobacillus fermentum; Saccharomyces cerevisiaeandLactobacillus brevis; andSaccharomyces cerevisiaeandLactobacillus fermentum)resulted in a significant increase in protein and starch digestibility. The pearl millet sprouts fermented with mixed culture containingS. diastaticusandL. brevishad the highestin vitrostarch digestibility, while the sprouts fermented with the culture containing 5.cerevisiaeandL. fermentumhad the highestin vitroprotein digestibility.
Physical and Compositional Characteristics of Beef Carcasses Selected for Leanness
Authors: BROWNING M. A. , HUFFMAN D. L. , EGBERT W. R. , JUNGST S. B.
Published: August 2006

Ten muscles and muscle groups were excised from each of eight typical (average yield grade 2.99) and eight lean (average yield grade 1.73) steer carcasses and analyzed to determine differences between carcass types. Lean carcasses (raw basis) were higher (P<0.05) in moisture and protein and lower (P<0.05) in fat, cholesterol and calories in comparison to typical carcasses. Typical carcasses (cooked basis) were higher (P<0.05) in fat and caloric content than lean carcasses. No differences (P>0.05) were found between carcass types (cooked basis) for moisture, protein, cholesterol, dry matter cholesterol, cooking loss or shear force value. Semitendinosus muscles from typical carcasses were rated higher (P<0.05) for juiciness and tenderness than from lean carcasses. Differences (P<0.05) were found among muscles for all traits measured.
Effect of Calcium Carbonate and Sodium Alginate on the Textural Characteristics, Color and Color Stability of Restructured Pork Chops
Authors: TROUT GRAHAM R. , CHEN C. M. , DALE SUSAN
Published: August 2006

The effects of factorial combinations of calcium carbonate (0.00 and 0.26%) and sodium alginate (0.0 and 0.7%) on the initial cooked tensile strength and texture profile analysis and the amount of discoloration during three months frozen storage of restructured pork chops were investigated. Calcium carbonate increased (p < 0.05) and alginate had no effect (p>0.05) on the tensile strength of the chops. Alginate decreased the hardness, cohesiveness, springiness, chewiness and gumminess of the restructured chops (p < 0.05). Chops that contained alginate and/or calcium carbonate had more initial discoloration than those that contained (1) no additives, (2) 0.75% NaCl plus 0.5% sodium tripolyphosphate, and (3) 0.75% NaCl plus 0.26% calcium carbonate but they did not discolor further during frozen storage.
Effect of Ionic Strength on Dynamic Viscoelastic Behavior of Myosin during Thermal Gelation
Authors: SANO TAKESHI , NOGUCHI SATOSHI F. , MATSUMOTO JUICHIRO J. , TSUCHIYA TAKAHIDE
Published: August 2006

The effect of ionic strength on the thermal gelation process of myosin was investigated by dynamic viscoelasticity measurements. The dynamic viscoelastic behavior of myosin was divided into three ionic strength groups. Each ionic strength group was closely related to the state of myosin molecules before the rise in temperature. Both the head and the tail portions of the molecule participated in the gel formation of myosin, but the temperature ranges differed. It was proposed that the first development of gel elasticity of myosin (30–45 °C) was attributed many to the tail portions of the molecules and that the second development (above 50 °C) was mainly to the head portions.
An Enzymatic Method Designed to Differentiate between Fresh and Frozen‐thawed Fish
Authors: KITAMIKADO NIANABU , YUAN CHONG‐SHENG , UENO RYUJI
Published: August 2006

A fluorometric method and a rapid paper test method were developed for differentiating fresh from frozen‐thawed fish. The methods were based on measurement of the activity of neutral β‐N‐acetylglucosa‐minidase. This enzyme, found in fish red blood cells, was inactive in intact cells but was activated when cells were disrupted by freezing and thawing. Both methods were applicable for testing most common edible fish prior to filleting and required about 20 min using a UV‐lamp.
Extraction of Cholesterol and Other Lipids from Dried Egg Yolk Using Supercritical Carbon Dioxide
Authors: FRONING G.W. , WEHLING R.L. , CUPPETT S.L. , PIERCE M.M. , NIEMANN L. , SIEKMAN D.K.
Published: August 2006

Supercritical carbon dioxide extraction was investigated for removal of cholesterol and lipid components from dried egg yolk. Four different combinations of pressure and temperature were used including 163 atm/40°C, 238 atm/45°C, 306 atm/45°C and 374 atm/55°C. As temperature and pressure were increased, more lipids and cholesterol were removed. Extraction at 306 atm/45°C or 374 atm/55°C removed approximately two‐thirds of the cholesterol. Phospholipids and protein were concentrated under the supercritical extraction conditions used. Sponge cake volume was significantly (P < 0.05) improved at extraction conditions of 163 atm/40°C, 238 atm/45°C and 306 atm/45°C, which may have been due to higher phospholipid and protein concentrations. Only extraction at 374 atm/55°C significantly (P < 0.05) impaired emulsion stability of egg yolk.
Whey Peptide Fractions Obtained with a Two‐Step Ultrafiltration Process: Production and Characterization
Authors: TURGEON S. L. , GAUTHIER S. F.
Published: August 2006

Whey protein concentrate (WPC) and heat‐treated WPC (90°C., pH 2.5, 10 min) were hydrolyzed with trypsin and chymotrypsin in an ultrafiltration reactor (PM 30). The total hydrolyzates were further fractionated (PM1) resulting in mixtures of polypeptides (M.P.) characterized by a high content of peptides larger than 5000 daltons and fractions made up of amino acids and small peptides (A.A.) rich in small components (<2000 daltons). The heat treatment of WPC modified the molecular weight profile of the fractions (M.P. and A.A.) by increasing their content in larger peptides (> 5000 daltons). Suggestions are given for possible food applications for the fractions produced.
Deamidation During Treatment of Soy Protein with Protease
Authors: SHIH FREDERICK F.
Published: August 2006

When soy protein was treated with protease in phosphate buffer, ammonia was generated in addition to the occurrence of peptide bond hydrolysis. The source of the ammonia was likely the nonenzymatic deamidation of glutamine in the hydrolysate because free glutamine was found to deamidate in phosphate buffer with or without protease. Both the glutamine deamidation and the deamidation during enzymatic proteolysis of soy protein were catalyzed by certain anions. Of the anions investigated, phosphate and bicarbonate were by far the most effective in that regard, borate only slightly effective, and acetate not effective at all.
Volatile Constituents of Loquat (Eriobotrya japonica Lindl.) Fruit
Authors: FRÖHLICH O. , SCHREIER P.
Published: August 2006

Concentrates of fresh, ripe Spanish loquat fruit were analyzed by HRGC, HRGC‐MS and HRGC‐FTIR. In total, 80 aroma substances were identified, of which 72 are reported for the first time as loquat fruit constituents. The major part of volatiles comprised alcohols and carbonyls. Quantitative HRGC revealed hexanal (2.4 mg/kg fruit pulp), (E)‐2‐hexenal (1.8 mg/kg) and benzaldehyde (0.7 mg/kg) as major aroma compounds.
Effects of Naturally Occurring Antioxidants on Peroxidase Activity of Vegetable Extracts
Authors: HEMEDA H.M. , KLEIN B.P.
Published: August 2006

The effectiveness of α‐tocopherol, two flavonoids (quercetin and ru‐tinic acid) and a cinnamic acid (chlorogenic acid) as inhibitors of peroxidase was evaluated. Four concentrations, 125, 250, 500 and 1000 mg%, of each compound were used. Crude extracts of tomatoes, carrots and eggplant were the sources of enzyme activity. Peroxidase activity of carrots and eggplant was inhibited more than that of tomato by all antioxidants. Alpha‐tocopherol was least effective in all systems and at all concentrations. Chlorogenic acid was most effective, followed by quercetin and rutinic acid.
Evaluation of Potent Odorants in Cucumbers (Cucumis sativus) and Muskmelons (Cucumis melo) by Aroma Extract Dilution Analysis
Authors: SCHIEBERLE P. , OFNER S. , GROSCH W.
Published: August 2006

The volatile components of cucumbers and muskmelons were analyzed by a technique which reveals the odorants having the highest odor units (ratio of the concentration to the odor threshold). (E/Z)‐2,6‐Nonadienal, followed by (Z)‐2‐nonenal and (E)‐2‐nonenal were the most significant odorants of cucumbers. The flavor of muskmelons was more complex. Methyl 2‐methylbutanoate, (Z)‐3‐hexenal, (E)‐2‐hexenal, and ethyl 2‐methylpropanoate were identified as the primary odorants.
Simultaneous Determination of Thermal Diffusivity and Heat Transfer Coefficient during Sterilization of Carrot Dices in a Packed Bed
Authors: CHANG S.Y. , TOLEDO R.T.
Published: August 2006

Carrot dices were heated under ultra‐high temperature sterilization conditions in a packed bed to quantify the effect of superficial fluid velocities on heat transfer coefficient (h) and obtain a value for thermal diffusivity (α). h and α were determined simultaneously under non‐constant heating fluid temperatures using a finite difference technique. Temperature profiles calculated using assumed h and α were matched with measured temperature at two points in a cube. Using best fit value for α of 1.94 × 10−7 m2/sec, mean h ranged from 600 to 1533 and 359 to 735 W/m2K for 0 and 1.58 cm/sec fluid velocity and 1 and 2 cm cubes, respectively. At 15.2 cm/sec, when a controlled heat transfer, calculated α was 1.86 ± 0.044 × 10−7 m2/sec.
Property Characterization of Peanut Kernels Subjected to Gamma Irradiation and Its Effect on the Outgrowth and Aflatoxin Production by Aspergillus parasiticus
Authors: CHIOU R. Y.‐Y , LIN C. M. , SHYU S.‐L.
Published: August 2006

Peanut kernels inoculated with Aspergillus parasiticus conidia and uninoculated kernels were gamma irradiated with 0 to 15 kGy using 60Co. Levels of 2.5 and 5.0 KGy were effective in retarding the outgrowth of A. parasiticus and reducing the population of natural mold contaminants. However, elimination of these molds was not achieved. When irradiated with doses higher than 10 KGy, seed germinations were inhibited, changes in proteins were observed and oil stabilities decreased. After 4 wk incubation of the inoculated kernels in a humidified condition, aflatoxins produced by surviving A. parasiticus ranged from 69.12 to 13.48 μg/g depending upon the original irradiation dose.
Ultrafiltration of Green Table Olive Brines: Influence of some Operating Parameters and Effect on Polyphenol Composition
Authors: BRENES M. , MONTAÑO A. , GARRIDO A.
Published: August 2006

Influence of several variables on ultrafiltration (UF) of green table olive brines was studied. Flux improved when temperature increased, although an interval of 30–40°C was recommended, especially when bentonite was used. To prevent darkening of regenerated brines for preservation for several days, sodium bisulfite had the best effect, although ascorbic acid was suggested. HPLC polyphenol analyses in the original brine, permeate and concentrate confirmed that UF removed a great amount of the polymerized polyphenols from the premeate. Simple phenols were not removed effectively, except for vanillin, caffeic acid and 4‐hydroxybenzoic acid which were substantially eliminated.
Analysis and Stability of the Sweetener Sucralose in Beverages
Authors: QUINLAN M. E. , JENNER M. Ft.
Published: August 2006

The stability of the sweetener sucralose in a range of prototype beverages was confirmed. Storage conditions were chosen to encompass the typical shelf life of the products under investigation plus some extreme conditions. The methods developed for the analysis of the beverages used high performance liquid chromatography with refractive index detection. The reproducibility of each method was determined by means of recovery experiments. Stored samples were also subjected to sensory evaluation. Sucralose was stable under all the conditions tested thus demonstrating the potential suitability of this sweetener in soft drinks.
Adenosine Triphosphate Catabolites as Flavor Compounds and Freshness Indicators in Pacific Cod (Gadus macrocephalus) and Pollock (Theragra chalcogramma)
Authors: GREENE D.H. , BERNATT‐BYRNE E.I.
Published: August 2006

Postmortem formation of 5′‐inosine monophosphate, inosine and hypoxanthine in Pacific cod and pollock fillets during chilled storage was monitored over a two week period. Accumulation of hypoxanthine in Pacific cod (Gadus macrocephalus) fillets proceeded more slowly than has been reported for Atlantic cod (Gadus morhua) but similar to North Sea cod (Gadus callarias L.). For both both cod and pollock, hypoxanthine was negatively correlated with flavor and desirability (p < 0.01), while both inosine and 5′‐inosine monophosphate were positively correlated with overall desirability (p < 0.01).
Proteolytic Degradation of Threadfin‐Bream Meat Gel
Authors: TOYOHARA HARUHIKO , KINOSHITA MASATO , SHIMIZU YUTAKA
Published: August 2006

The textural degradation of threadfin‐bream meat gel accompanying the breakdown of the myosin heavy chain was caused not by a heat‐stable alkaline proteinase (HAP) but by a newly found gel degradation‐inducing factor (GIF). GIF as well as HAP was recovered in the sarcoplasmic fraction, but GIF was separated from HAP by gel filtration on Ultrogel AcA 34. This factor showed strong proteolytic activity against the myosin heavy chain at pH 7.0 in the presence of 2.5% NaCl.
Changes in California Naval Orange Juice during Commercial Debittering
Authors: KIMBALL DAN A. , NORMAN SETH I.
Published: August 2006

The nutritional and compositional changes (via adulteration screenings) in California navel orange juice during commercial debittering using a hydrophilic absorbent were studied. Both reconstituted and freshly extracted juices were analyzed. There were significant reductions in limonin, citrus oils and pulp. Citrus oils and pulp can be replenished without violation of federal standards of identity. Increases in mineral content resulted from the use of mineral‐laden water for reconstituting concentrates before treatment and not from the use of the absorbent.
Aflatoxin‐producing Ability of Spores of Aspergillus parasiticus Exposed to Gamma Radiation
Authors: SHARWIA ARUN , PADWAL‐DESAI S.R. , NAIR P.M.
Published: August 2006

When compared with the unirradiated spores, gamma irradiated spores of aflatoxin‐producing fungi did not produce more aflatoxin after inoculation on autoclaved rice. The greatest amount of aflatoxin was produced by the inoculum of the colonies obtained from unirradiated spore suspension, whereas, the inoculum of colonies from irradiated spore suspension produced comparatively lower amounts of the toxin in synthetic glucose‐salt medium. The studies indicated that radiation did not increase the aflatoxin‐producing potential of the fungus.
Flavor Characteristics of Forage‐ and Grain‐Fed Beef as Influenced by Phospholipid and Fatty Acid Compositional Differences
Authors: LARICK D. K. , TURNER B. E.
Published: August 2006

Neutral lipid (NL) and phospholipid (PL) fractions and their corresponding fatty acid (FA) profiles from the L. dorsi of Angus‐Hereford heifers (n=27) were compared as a function of forage grazing (FG) and time in the feedlot after grazing (DIF) on pasture. There were no differences in total PL content or FA composition of the individual PL as influenced by initial FG. As DIF increased, there was an increase in PL concentration and significant changes in the FA composition of the total PL and several of the individual PL fractions, separated by high performance liquid chromatography. Total PL content and FA content of the individual PL were significantly correlated with differences in the flavor characteristics of ground beef which were determined by a descriptive panel.
Thermal Destruction of Listeria monocytogenes in a Meat Slurry and in Ground Beef
Authors: BOYLE D. L , SOFOS J. N. , SCHMIDT G. R.
Published: August 2006

Thermal destruction of Listeria monocytogenes cells was determined in phosphate buffer, a meat slurry (20% ground beef/80% water) and in ground beef. D‐values at 60°C, 65°C and 70°C in phosphate buffer, and in the meat slurry were 0.63, 0.29 and 0.15, and 2.54, 0.75 and 0.23 min, respectively. Heating of ground beef (80% lean) in a 75°C water bath to 50°C, 60°C or 65°C required 6.2, 8.4 and 10.6 min, respectively, and resulted in 0.2‐0.9, 1.6‐3.4 and 4.4‐6.1 log reductions in L. monocytogenes cells, from the initial inoculation level of 8.08 log CFU/g. Viable cells were also detected after cold (21 days) or selective enrichment (24 hr) in eight out of nine samples of ground beef inoculated with 7.84‐8.08 log CFU/g and cooked to 70°C.
Textural and Chemical Characteristics of Recombined Precooked Beef Chuck Roasts as Influenced by Boning Time and Salt Level
Authors: MANN T.F. , REAGAN J.O. , JOHNSON LP. , LYON C.E. , MABRY J.W. , MILLER M.F.
Published: August 2006

The effects of hot‐boning (HB) and salt level (SL) (0, 0.5, 1.0%) on recombined precooked roasts from three beef chuck recombined whole muscles were investigated using a system that employed electrical stimulation, blade tenderization, vacuum massage and the addition of phosphate. SL and muscle type (MT) significantly affected proximate composition (protein, fat and moisture). Maximum yields were obtained with hot‐boned treatments at the highest salt level. Instron measurements were affected by MT, HB and SL. Results of this study indicate that binding of large meat pieces together to form low calorie recombined, precooked roasts can be achieved.
Effect of Heating Rate on Meat Batter Stability, Texture and Gelation
Authors: BARBUT S. , MITTAL G.S.
Published: August 2006

The effects of four heating rates (0.31, 0.51, 1.22, and 1.62°C/min) on the gelation, stability and texture of meat batters containing 2.5 and 1.25% salt were studied. In general, slower heating rates resulted in higher modulus of rigidity (G) values, and salt reduction resulted in lower G values. All the low salt treatments, except the 1.62°C/min treatment, showed a structural breakdown (above 67°C) when the scanning rigidity monitor was used. However, in the texture profile analysis (samples cooked to 50, 60 and 70°C) no structural breakdown was observed. Therefore, special care should be given to interpreting gelation profile results.
An Evaluation of Simple Methods for Following Rigor Development in Fish
Authors: KORHONEN REINO W. , LANIER TYRE C. , GIESBRECHT FRANCIS
Published: August 2006

Measurements obtained with a simple rigorometer (muscle tension measuring device) were found to correlate well with measurements of the relative ATP/IMP content ratio (258/250 nm absorbance ratio of perchloric extracts), muscle pH, and visual measurements of stiffness in whole fish (tilapia, Areochromis aureus) during rigor development. These simple tests yielded measurements which clearly differentiated the effects of ante‐mortem stress on the rate of onset of rigor mortis and associated biochemical changes in the fish muscle.
Degradation of Oval‐Filefish Meat Gel Caused by Myofibrillar Proteinase(s)
Authors: TOYOHARA HARUHIKO , SAKATA TETSUO , YAMASHITA KAZUYUKI , KINOSHITA MASATO , SHIMIZU YUTAKA
Published: August 2006

The textural degradation of oval‐filefish meat gel accompanying the increase of peptides and the breakdown of myosin heavy chain was caused by proteinase(s) tightly associated with myofibrils. Leupeptin and n‐butanol inhibited the proteolytic activity to some degree. The existence of an endogenous inhibitor for the proteolytic activity in the sarcoplasm was also demonstrated.
Amino Acid Hydrolysate from Crab Processing Waste
Authors: JASWAL AMRIK S.
Published: August 2006

Variables affecting acid hydrolyses were investigated for their efficacy in producing high quality amino acid hydrolysates from crab waste protein for its potential use in specialized animal feed and other food products. In a preliminary trial, 5N HCl was found to be a suitable hydrolyzing agent based on the presence of nihydrin‐positive substances. Amino acid yields from a 12 hr hydrolysis time varied from about 28–31%, increased marginally to 29–32% with 24 hr of hydrolysis, but decreased with hydrolysis time in excess of 24 hr. Depending upon hydrolysis time, approximately 42–44% of the total amino acids were essential amino acids: principally leucine, arginine, valine, and threonine. The remaining nonessential amino acid fraction was composed mainly of glutamic acid, aspartic acid and glycine.
Comparison of Vapor and Liquid Isotherms for Casein and Casein‐Sucrose Mixture
Authors: MISTRY ATUL , STEINBERG M.P. , SCHMIDT S.J. RICHARDSON
Published: August 2006

Hydration by vapor sorption and liquid water addition for the effect on sorption isotherms of casein and a casein‐sucrose mixture was compared. Both isotherm data and NMR relaxation rates were obtained from the same samples. Data showed biphasic linear plots with breaks at the same water activity (aw). At a given moisture content, liquid hydration of casein showed a lower aw and a lower NMR mobility than the vapor sorbed samples. The casein‐sucrose mixture showed the opposite. As aw was increased above 0.90, casein alone showed decreasing difference between vapor and liquid hydration while the mixture showed rapidly diverging lines. These isotherm differences between vapor and liquid hydration were corroborated by NMR.
Unique Hydration Behavior of Potato Starch as Determined by Deuterium Nuclear Magnetic Resonance
Authors: YAKUBU PHILLIP I. , BAIANU ION C. , ORR PAUL H.
Published: August 2006

Deuterium Nuclear Magentic Resonance (NMR) measurements at 4.7 Tesla revealed a unique hydration behavior of potato starch that involved the presence of a tightly bound water population with anisotropic motions within the potato starch granule, even in the presence of excess, bulk water in potato starch slurries. Well‐defined powder patterns with residual deuterium quadrupole splittings of about 1 kHz were also observed at 20°C for raw potato tubers. Three other water populations, a weakly bound, a surface‐trapped, and a bulk water population, were also present up to 60% starch and were in fast exchange with each other at room temperature, resulting in a broadened, single Lorentzian 2H NMR peak. These three water populations were absent below 35% moisture content in potato starch, but not in corn starch. The unique hydration properties of potato starch might be important for novel processing methodology.
Effect of Cooking on Firmness, Trypsin Inhibitors, Lectins and Cystine/Cysteine content of Navy and Red Kidney Beans (Phaseolus vulgaris)
Authors: DHURANDHAR N.V. , CHANG K.C.
Published: August 2006

The effect of cooking on firmness, trypsin inhibitor (TI) and lectin activities, and cystine/cysteine (Cys) of navy and red kidney beans was investigated. Beans were soaked and cooked in an open‐kettle at various temperatures and periods. Navy beans canned by two methods were used for comparisons with the open‐kettle cooked beans. The TI activity, lectin activity and Cys content decreased with increasing temperature and/or period. Under some of the cooking conditions, less than 5.5% and 0.1% of TI and lectin activities, respectively, were retained, though the firmness of beans was palatable. Canned navy beans did not have lectin activity but had less than 5% residual TI activity.