bluuebunny/crossref_metadata_2025_split huggingface dataset:
Partial Separation and Characterization of Papaya Endo‐ and Exo‐Polygalacturonase
Authors: CHAN HARVEY T. , TAM STEVEN Y.T. 
Published: August 2006

ABSTRACTExo‐ and endo‐polygalacturonases (EC 3.2.1.40 and EC 3.2.1.15) in papayas were extracted, purified 20‐ and 90‐fold, respectively, and characterized. Both enzymes functioned optimally at pH 4.6 and 45°C. Heat inactivation of the papaya PGases was biphasic and both phases followed first order kinetics. Decreasing the pH from 4.6 to 3.6 decreased the time required for their heat inactivation. The activation energies for the thermal inactivation at pH 3.6 and 4.6 were 85 and 92 kcal/mol, respectively, for endo‐PGase (PG I) and 140 and 102 kcal/mol, respectively, for exo‐PGase (PG II). The apparent molecular weight was determined by gel filtration to be 164,000 daltons for PG I and 34,000 daltons for PG II.
Thermal Destruction of Vitamin B6 Vitamers in Buffer Solution and Cauliflower Puree
Authors: NAVANKASATTUSAS S. , LUND D. B. 
Published: August 2006

ABSTRACTThermal degradation rates of pyridoxal (PL‐HCl), pyridoxine (PN‐HCl) and pyridoxamine (PM‐2 HCl) in 0.1 M phosphate buffer (pH 7.20) were determined over the temperature range 110‐145°C using HPLC procedures. Thermal degradation of PM‐2 HCl was modelled by a pseudo‐first order rate constant. Thermal degradation of PN‐HCl and PL‐HCl was modelled by a 1.5 order and second order model, respectively. The temperature dependence of all three rate constants could be described by the Arrhenius equation. None of the degradation products from any of the vitamers exhibited antivitamin activity. Thermal degradation rates of vitamin B6 in cauliflower puree were measured over the temperature range 106‐138°C and found not to be described by a first‐order model. The activation energy was markedly lower in this food system than in the model system and emphasizes the importance of conducting experiments on real food systems. The activation energy is in the range reported for several other water soluble nutrients.
A Computer Assisted Analysis of Some Theoretical Rate Effects in Mastication and in Deformation Testing of Foods
Authors: PELEG M. , NORMAND M. D. 
Published: August 2006

ABSTRACTSimplified rheological models, with relaxation times comparable to those of solid foods, were used to simulate stress strain relationships at rates comparable to those in mastication and in common deformation tests (linear velocities on the order of 100 and 1 cm min−1 respectively). The simulations included the regimes of constant deformation and strain rates and a sinusoidal deformation pattern. They demonstrated that the information in sensory perception and mechanical testing can be different in both kind and magnitude largely due to the rheological character of the food and its relaxation time and to a lesser extent, to the exact deformation regime.
Factors Influencing the Production and Activity of a Streptococcus thermophilus Lipase
Authors: DeMORAES JOSE , CHANDAN R. C. 
Published: August 2006

ABSTRACTThe cells from 32 strains were disrupted by pressure. All the strains except two showed lipase activity. Optimum temperature for lipase production was 44°C. Production of lipase was inhibited by addition of butter oil (29%), milk (41%) and casein (12%) and stimulated by soybean oil (39%), cream (27%) and corn oil (21%) to the medium. The enzyme was stable when stored at 37°C and 45°C for 1 wk. The enzyme was partially inactivated by pasteurization treatment (65°C/30 min). Optimum temperature and pH for lipase activity was 45°C and 9.0, respectively. The enzyme was relatively more active toward tributryin than toward natural lipids.
Inhibition of Pseudomonas fluorescens by Hydroxycinnamic Acids and Their Alkyl Esters
Authors: BARANOWSKI JOHN D. , NAGEL CHARLES W. 
Published: August 2006

ABSTRACTAlkyl esters of six hydroxycinnamic acids and cinnamic acid were evaluated in a liquid medium for their effectiveness in inhibiting the growth of Pseudomonas fluorescens, a bacterium commonly implicated in food spoilage. Compounds were tested at concentrations of 0–250 ppm, using turbidity as a measurement of growth. At 125 ppm, esters of p‐coumaric and caffeic acids were more inhibitory than either methyl or propyl paraben. Methyl esters of methoxylated cinnamic acids were much less inhibitory than the methyl esters of the corresponding positional hydroxylated cinnamic acids. The results indicate that esters of certian of these naturally occurring hydroxycinnamic acids may be useful as food additives to extend shelf life by inhibiting microbial growth.
Bone and Plasma Protein Extracts in Sausages
Authors: CALDIRONI H. A. , OCKERMAN H. W. 
Published: August 2006

ABSTRACTProteins from bones were extracted (4°C) at pH 10 and emulsifying capacity (EC) of bone protein extracts (BPE) were compared with beef muscle (BMP) and blood plasma (PP) proteins. PBE showed the lowest EC (ml oil/g total protein) values but they were similar to BMP when the EC was calculated on a soluble protein basis. EC values from BPE were enhanced by mixing those proteins with BMP. Sodium‐pyrophosphate improved EC values primarily at low protein concentrations. Water‐holding capacity (WHC) of the BPE, BMP and PP were obtained and a close correlation (r = 0.99) was found between WHC and the fat/protein ratio of the samples. Up to 10% BPE plus 5% PP and both plus 0.4% of sodium pyrophosphate were included in the manufacture of cooked sausages. These products were ranked as acceptable by a sensory panel.
Effect of Sodium Nitrite Concentration, Sodium Erythorbate and Storage Time on the Quality of Franks Manufactured from Mechanically Deboned Turkey
Authors: WESLEY ROGER L. , MARION WILLIAM W. , SEBRANEK JOSEPH G. 
Published: August 2006

ABSTRACTThe effects of sodium nitrite (0‐156 ppm), sodium erythorbate (0 or 550 ppm) and storage time (up to 10 wk at 4°C) were measured on the chemical and sensory properties of turkey franks formulated largely from mechanically deboned turkey (MDT), Residual nitrite in the finished product was proportional to that incorporated at time of formulation and was reduced by using small initial amounts in combination with the maximum allowable erythorbate (550 ppm). Acceptable cured color in turkey franks was achieved with the incorporation of 50 ppm of nitrite. Erythorbate effectively increased cured color development and stability, particularly with smaller amounts of nitrite. Rancidity development in turkey franks was not of major significance. Even so, the presence of erythorbate imposed further control of oxidative changes in lipids. Maximum cured flavor development occurred with 50–100 ppm nitrite.
Dried Pork as Influenced by Nitrate, Packaging Method and Storage
Authors: OCKERMAN H. W. , KUO J. C. 
Published: August 2006

ABSTRACTA new technique was developed to produce high quality, uniform and attractive thin sliced, cured dried pork. The effects of nitrate, packaging method and storage time on residual nitrite, TBA values, sensory properties and microbiological counts were determined. Residual nitrite decreased with increased storage time at 3 ± 1°C. The addition of nitrate plus vacuum packaging caused a greater residual nitrite level and a lower TBA value during storage. Nitrite and/or nitrate acted as an antioxidant to retard oxidative rancidity (TBA value). Dried pork manufactured by the technique described had no major rancidity problem and had an acceptable shelf life. Total aerobic plate counts, lactic acid producing microbial counts and total anaerobic counts were not affected by nitrate or packaging methods. Coliforms, molds and yeasts were not found in this dried pork.
Effect of Changes in Intermuscular and Subcutaneous Fat Levels on Cholesterol Content of Raw and Cooked Beef Steaks
Authors: RHEE KI SOON , DUTSON THAYNE R. , SMITH GARY C. 
Published: August 2006

ABSTRACTMuscle, intermuscular (seam) fat and subcutaneous fat dissected from boneless rib steaks (U.S. Choice quality grade; USDA yield grade 1 to 5) were analyzed for cholesterol content. For raw steaks, the cholesterol content (wet basis) in the fat fractions was greater than 150% of that in the muscle fraction; the difference diminished greatly when steaks were cooked to an internal temperature of 70°C. On an average of all yield grades, cooked intermuscular fat and subcutaneous fat contained about 108 and 122%, respectively, of the cholesterol content in cooked muscle. The percentage of total cholesterol in raw and cooked steaks that was contributed by the combined fat fractions increased significantly with numerical increases in the USDA yield grade. However, the amount of cholesterol per gram of the whole steak was not significantly different among the five yield grades.
Sampling Methods for Detection of Salmonella in Raw Chicken Carcasses
Authors: D'AOUST J. Y. , STOTLAND P. , BOVILLE A. 
Published: August 2006

ABSTRACTDetection of Salmonella in thaw water, pericloacal skin and whole carcass rinse samples from naturally contaminated broiler chickens was compared. Of 100 birds tested, 70 were found to contain salmonellae by the three sampling techniques combined; the median level of contamination was 0.27 salmonellae/100g eviscerated carcass weight. Recovery with the whole carcass rinse technique (93%) was significantly greater than that obtained with thaw water (63%) and skin (74%) methods; performance of the latter two methods was not statistically different. Thaw water does not provide a reliable index of Salmonella contamination and therefore is not a suitable method for the nondestructive analysis of poultry carcasses. Selective enrichment in tetrathionate brilliant green broth and plating on bismuth sulfite agar identified the greatest number of contaminated carcasses under all sampling conditions.
Effect of High Doses of High and Low Intensity UV Irradiation on Surface Microbiological Counts and Storage‐Life of Fish
Authors: HUANG YAO‐WEN , TOLEDO ROMEO 
Published: August 2006

ABSTRACTUltraviolet (UV) irradiation at 254 run and doses of 300 mWs/cm2 from a photochemical reactor (16.6 min at 300 μW/cm2) or 4.8 Ws/cm2 from a high intensity UV‐C lamp (40 sec at 120–180 mW/cm2 reduced surface microbial count on mackerel by two to three log cycles. UV treated mackerel wrapped in 1 mil polyethylene and packed in ‐1°C ice had at least a 7 day longer shelf life than conventional ice‐packed untreated controls. Spray washing with water containing 10 ppm chlorine by itself or in combination with UV irradiation was necessary to reduce surface counts on rough surfaced fish to the same extent as that on smooth surfaced fish. When UV irradiated and packed in 0°C ice, surface microbial counts on vacuum packaged mackerel lagged by 4 days those on mackerel wrapped in 1 mil polyethylene.
Microwave Processing to Destroy Salmonellae in Corn‐Soy‐Milk Blends and Effect on Product Quality
Authors: BOOKWALTER G. N. , SHUKLA T. P. , KWOLEK W. F. 
Published: August 2006

ABSTRACTEnriched corn‐soy‐milk (CSM) blends were inoculated with Salmonella senftenberg and packed in 50‐lb (22.7 kg) bags. The inoculated product and CSM bags containing natural salmonellae contamination were heated from 21° to 56.7°C through 82.2°C in 3.9 – 10 min, respectively, using a 60 Kw (2450 MHz) continuous microwave tunnel, and then palletized with and without 4‐cm spacers between rows. Spacer palletized bags cooled to 43°C after 9.7 hr with moving air and after 23.3 hr without moving air, but 60 hr was required with no spacers. Initial most probable numbers (MPN) of 4 × 102 cells/g for S. senftenberg were reduced 102‐fold to 105‐fold after processing at 56.7° through 82.2°C, respectively. Nutritional damage occurred at process temperatures of 77.8° and 82.2°C. At 61.1° and 67.2°C, MPN were reduced 2 × 103‐fold with no significant change in rheology, moisture, color, vitamins A and B1, available lysine, and protein efficiency ratios.
Properties and Uses of Horny and Floury Endosperms of Corn
Authors: KIKUCHI K. , TAKATSUJI I. , TOKUDA M. , MIYAKE K. 
Published: August 2006

ABSTRACTOrdinary corn kernel endosperm is composed of horny and floury portions. Corn varieties having different endosperm were investigated. Their chemical composition was almost identical, but in tissue structure the floury endosperm is soft and the horny endosperm is hard. The starch isolated from floury endosperm is easier to gelatinize, and higher in viscosity, swelling value, and α‐amylase digestibility than the starch from horny endosperm. The floury endosperm is superior to the horny endosperm in such baking products as bread and cookies.
The Standard Scales of Texture: Rescaling by Magnitude Estimation
Authors: CARDELLO ARMAND V. , MATAS ALINA , SWEENEY JAMES 
Published: August 2006

ABSTRACTFood items comprising the six “standard scales” of texture [Szczesniak et al., J. Food Sci. 28: 397 (1963)] were rescaled using the psychophysical method of modulus‐free magnitude estimation. The category scale position of each food item on the standard scales was plotted against the geometric mean magnitude estimate for that item. The category (interval) scale data were concave downward relative to the magnitude (ratio) scale data. These results underscore the differences that can be obtained by using either interval or ratio procedures and suggest that the attributes of “hardness,”“chewiness,”“fracturability,”“viscosity,”“gumminess,” and “adhesiveness” can be classified as “prothetic” continua.
GLC‐MS Analysis of Fatty Acids From Five Black Walnut Cultivars
Authors: SENTER S. D. , HORVAT R. J. , FORBUS W. R. 
Published: August 2006

ABSTRACTThe lipids from kernels of five black walnut cultivars were extracted by solvent extraction and the fatty acids were analyzed as their methyl esters by GLC‐MS analyses. Twenty‐one fatty acids were identified in each cultivar. Five acids, palmitic, stearic, oleic, linoleic and linolenic, were present in quantities greater than 1% of total lipids present. Quantities of the individual fatty acids varied significantly among cultivars (P > 0.05) except for palmitic. Linoleic was the predominant fatty acid in all cultivars. Oleic and linoleic comprised greater than 85% of the lipids present in the walnut kernels.
Development and Use of A Proficiency Test Specimen for Paralytic Shellfish Poisoning
Authors: ARES JOHN A. , DYMSZA HENRY A. 
Published: August 2006

ABSTRACTA proficiency test specimen was developed for evaluating laboratory precision in paralytic shellfish poisoning bioassays. Such a specimen is needed since much of health and economic consequence depends on an analyst's precision in measuring the toxin. Therefore, after testing clams, mussels, and mashed potato matrices, a test specimen composed of saxitoxin dihydrochloride and hydrated potato flakes was selected. Samples containing two toxin levels were sent to 14 collaborating laboratories. Analysis of results identified errors arising from poor dilution techniques. Recovery percentages and variances of mashed potato were comparable to those previously reported with shellfish matrices. Use of the potato matrix appears to offer cost and convenience advantages.
Centralized Packaging of Beef Loin Steaks with Different Oxygen‐Barrier Films: Microbiological Characteristics
Authors: VANDERZANT C. , HANNA M. O. , EHLERS J. G. , SAVELL J. W. , SMITH G. C. , GRIFFIN D. B. , TERRELL R. N. , LIND K. D. , GALLOWAY D. E. 
Published: August 2006

ABSTRACTVacuum packaged beef strip loins (n = 72) were stored (2° 1°C) for either 0,12 or 24 days before fabrication; steaks were packaged and displayed (2°C or 7°C) up to 6 days in oxygen‐permeable film or up to 30 days in vacuum packages (medium or high oxygen‐barrier film). For steaks displayed in oxygen‐permeable film, Pseudomonas spp. were a considerable (25–49%) or dominant (>50%) part of the microflora. The microflora of vacuum‐packaged steaks from 0 day loins was dominated by a combination of hetero‐ and homofermentative Lactobacillus spp.; when vacuum‐packaged steaks were from 12 and 24 day loins, the microflora was in most cases dominated by the heterofermentative Lactobacillus cellobiosus.
Safety and Sensory Evaluation of Canned Rice
Authors: SHARP R. N. , KATTAN A. A. , SHARP C. Q. , COLLINS J. A. 
Published: August 2006

ABSTRACTRice, thermally canned as an acid food, was studied to determine if the process would provide a product which was safe and acceptable. Heat penetration studies showed that heat transfer was initially by convection and then by conduction as the rice imbibed sufficient water to restrict the convection currents. Although heat penetration studies indicated that a temperature of 180°F (82°C) was reached in 8 min and inoculated packs processed for 20 minutes in actively boiling water did not support bacterial growth, 30 minutes processing time was required to attain optimum quality. Canned rice, rice with textured vegetable protein (TVP®), Spanish rice, and Spanish rice with TVP were rated acceptable in general appearance, texture and taste. Experimental Spanish rice was rated superior to one and equal to two commercial Spanish rice products in general appearance and flavor.SUMMARYTHESE DATA indicate that the process described by Sharp et al. (1981) produced an adequately processed canned rice product. Processing in actively boiling water for 20 min was adequate to destroy the vegetative cells in an inoculated pack while a pH of 4.4 prevented spores from germinating. The potential of the processing method was demonstrated by the development of four products that were rated acceptable.
Corn Distillers' Dried Grains with Solubles and Corn Distillers’Dried Grains: Dry Fractionation and Composition
Authors: WU Y. VICTOR , STRINGFELLOW ARTHUR C. 
Published: August 2006

ABSTRACTCorn distillers' dried grains with solubles (CDGS) and corn distillers' dried grains (CDG) at various moisture and fat contents were pin milled and screened. Fractions of CDGS and CDG contained from 11.4–45.7% and 12.5–49.6% protein, respectively (dry basis), compared with 30% for CDGS and 25% for CDG. The highest protein shifts were obtained when CDGS at initial moisture of 21% was ground twice at 14,000 rpm and CDG at initial moisture of 21% was ground once at 14,000 rpm. Fat, ash, dietary fiber contents, and amino acid composition of CDGS and CDG fractions were also determined.
Sulfur Amino Acid Stability. Effects of Processing on Legume Proteins
Authors: MARSHALL H. F. , CHANG K. C. , MILLER K. S. , SATTERLEE L. D. 
Published: August 2006

ABSTRACTFour legume protein sources: peanuts, dry beans, alfalfa and soybeans were processed in laboratory, pilot plant and commercial processing facilities. Raw ingredients, intermediate and final protein products were analyzed for total and reactive cysteine/cystine (Cys), total methionine, methionine sulfoxide and methionine sulfone. Lysine, total and reactive, was determined on each legume protein sample. Processing of soybeans, peanuts and alfalfa into protein products caused no significant loss of lysine or the sulfur amino acids. The production of a protein concentrate from dry beans resulted in a significant loss of Cys. One commercial soy isolate was found to contain 51% of its total methionine as methionine sulfoxide, yet its Cys was unaffected.
Perception of Texture by Trained and Consumer Panelists
Authors: CARDELLO ARMAND V. , MALLER OWEN , KAPSALIS JOHN G. , SEGARS RONALD A. , SAWYER F. MILES , MURPHY CLAIRE , MOSKOWITZ HOWARD R. 
Published: August 2006

ABSTRACTFour experiments were conducted to assess the relationships between judgments of the perceived texture of foods by trained and consumer panelists. In Experiment 1, no differences were observed between trained texture profile panelists and naive consumers in a similarities scaling task. In Experiments 2 and 3, good linear correlations were observed between scalar judgments of texture, although a broader perceptual range was evidenced for trained panelists. In Experiment 4, psychophysical exponents of texture were found to be larger for trained than for consumer panelists, and judgments of acceptability also differed between the two groups. It was concluded that, through experience, trained texture profile panelists develop a broader perceptual range of textures, but that regression equations can be developed to relate these data to consumer data.
Surface Tension and Foaming of Protein Solutions
Authors: KITABATAKE NAOFUMI , DOI ETSUSHIRO 
Published: August 2006

ABSTRACTThe relationship between surface tension and foamability of protein solutions was examined. Proteins including egg albumin, soybean protein, casein, milk whey protein and gelatin were used. Foamability was expressed as “foaming power” which corresponded to the ratio of gas volume to the liquid volume in the foam. The absolute surface tensions of protein solutions were not correlated to foamability, but the rate constant of surface tension decay of protein solutions was significantly correlated to foamability of protein solution.
Detection of Microbial Contamination Utilizing an Infrared CO2 Analyzer
Authors: THRELKELD C. H. 
Published: August 2006

ABSTRACTInfrared (IR) analysis of headspace gas for the presence of CO2 was evaluated as a method of nondestructively sampling and segregating microbiologically contaminated products. Approximately 1.8 million 7‐oz bottles containing citrus juices and fruit drinks were inspected and segregated based on IR CO2 analysis. Comparison of IR analysis with conventional plating methods indicated 89% of the samples determined to be positive by conventional methods were also detected by IR analysis. False negatives were found to be the result of nonfermentative microorganisms in over 80% of the contaminated samples not detected by IR analysis. Nonfermentative organisms were identified and effects on product were evaluated. The expected contamination rate was 5.3% compared to 6.3% contamination detected by IR analysis.SUMMARYIN SUMMARY, an IR CO2 analyzer was utilized successfully to inspect 100% of product suspected of microbial contamination. When proper procedures were followed, contaminated product was detected and removed for destruction while good product was recovered for subsequent shipment to consumers. This system is advantageous because it allows for a 100% nondestructive inspection, is comparable to conventional plating methods in determining the presence of microbial contamination, and can be automated to a high degree. It is probable that automated container handling would have resulted in fewer false positives due to tilting of bottles as well as elimination of false negatives containing CO2 which were the result of insufficient time of analysis. Disadvantages include the requirement of an IR detectable microbial product, a container or package adaptable to an IR transmission or reflection type analysis, and a considerable cost for equipment. Any product contaminated by fermentative microorganisms and packaged in glass containers having a headspace of approximately 0.5 inch could be inspected by the methods described here. Justification for the cost of equipment would depend on the amount of contaminated product and the expected recovery rate. It is quite possible that future application of IR analysis could include monitoring food process streams for indicators of microbial contamination.
Determination of D‐Amino Acids in Some Processed Foods and Effect of Racemization on In Vitro Digestibility of Casein
Authors: BUNJAPAMAI S. , MAHONEY R. R. , FAGERSON I. S. 
Published: August 2006

ABSTRACTSeveral processed foods and controls were analyzed by gas chromatography for the presence of D‐amino acids. The concentration of each of the D‐amino acids detected in the processed foods was approximately the same as that in the controls except that D‐aspartic acid was significantly higher in dark toast surface and extruded soy flour. In vitro digestibility of casein which was alkali‐treated to cause racemization, but without lysinoalanine (LAL) formation, was essentially the same as that of racemized casein containing LAL, but was lower than that of nonracemized control casein.