bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Affecting the Water Retention of Beef. V. Variation of the Zinc‐Containing Enzymes
Authors: BERMAN MORRIS D.
Published: August 2006

A comparative study of the lactic dehydrogenase, glutamic dehydrogenase, carbonic anhydrase, zinc, water‐soluble nitrogen, moisture, and protein content of six different muscles from three bovine animals was conducted in an investigation of factors contributing to differences in the ultimate pH values of the muscles. The results indicate that variation was considerable in content of zinc, lactic dehydrogenase, glutamic. dehydrogenase, and carbonic anhydrase. A highly significant direct correlation was found between pH and zinc content, and a highly significant inverse correlation between lactic dehydrogenase and pH. Lactic dehydrogenase significantly correlated with soluble nitrogen content. No relation was found between glutamic dehydrogenase, carbonic anhydrase, and pH.
Oxidative Damage to Amino acids, peptides, and proteins by Radiationa
Authors: AMBE K. S. , TAPPEL A. L.
Published: August 2006

Oxidative damage to amino acids, peptides and proteins by radiation was measured as total peroxides and thiobarbituric acid reactants. Two types of thiobarbituric acid reactants were formed in low yields.
Cellulose Crystallinity and the Reconstitution of Dehydrated Carrots
Authors: STERLING CLARENCE , SHIMAZU FUMINAGA
Published: August 2006

Blanched and unblanched dice of carrot phloem were dehydrated at two different rates and stored for periods up to 6 months. The rehydrated volume was always greater for blanched dice than for unblanched. In all samples, the rehydrated volume decreased as a result of storage. No consistent differences among samples could be attributed to differences in rate of dehydration. Cellulose, extracted from the dice, was examined for crystalline content by water‐vapor sorption, X‐ray diffraction, iodine adsorption, enzymatic digestibility, and density methods. All methods agreed in showing a higher crystallinity in unblanched than in blanched samples, a continual increase in crystallinity in all samples as storage time increased, and no notable differences in crystallinity as a result of different dehydration rates.
Nutritive Value of Central American Beans. IV. The Essential Amino Acid Content of Samples of Black Beans, Red Beans, Rice Beans, and Cowpeas of Guatemalaa
Authors: BRESSANI R. , ELIAS L. G. , NAVARRETE D. A.
Published: August 2006

The rice bean (Phaseolus calcaratus), cowpea (Vigna sinensis), red bean, and three black bean (Phaseolus vulgaris) samples grown in Guatemala, were found to be fairly similar in chemical composition. Average percentage values were: moisture 14.5, protein 22.3, ether extract 1.3, ash 3.5, crude fiber 6.0, and carbohydrate 52.4. The range in amino acid content, expressed as mg of amino acid per gram of nitrogen, was: arginine 356‐528, histidine 159‐232, isoleucine 143‐339, leucine 189‐260, lysine 322‐544, total sulfur‐containing amino acids 80‐94, phenylalanine plus tyrosine 362‐471, tryptophan 52‐73, threonine 215‐348, and valine 191‐383. The cowpea sample was higher in lysine; the rice bean and red bean samples were higher in tryptophan. The isoleucine and valine contents were lower, and the leucine higher, in the red beans than in the other samples. When compared with the amino acid pattern of the FAO Reference Protein, methionine plus cystine was the most‐limiting amino acid, and leucine and tryptophan respectively the second‐ and third‐most limiting. All the samples contained high amounts of lysine, making beans a good source of this amino acid.
Volatile Flavor of Sauerkraut.a,b Gas Chromatographic Identification of a Volatile Acidic Off‐Odor
Authors: VORBECK MARIE L. , MATTICK LEONARD R. , LEE FRANK A. , PEDERSON CARL S.
Published: August 2006

A method is presented for gas chromatographic identification of the chain length and structure of methyl esters of lower‐molecular‐weight fatty acids. The chemical identity of the “cheese‐like” off‐odor of sauerkraut was established. Abnormally high concentrations of n‐propionic, n‐butyric, and n‐caproic acids were found in samples of kraut that had been graded low because of this off‐odor defect. A very poor sample that had been discarded, contained isobu‐tyric and isovaleric acids in addition to n‐propionic, n‐butyric, n‐valeric, and n‐caproic acids. In this sample, n‐butyric acid was found in the largest concentration—103 ppm.
An Investigation of Varietal Differences in the Iodine‐Binding Capacities of Crystalline Rice Amylosesa
Authors: PHILLIPS ALLEN T. , WILLIAMS VIRGINIA R.
Published: August 2006

Purified amyloses have been obtained from four widely different varieties of rice by alcohol fractionation of the corresponding starch. Each variety of amylose was found to bind 18.9 mg of iodine per 100 mg of amylose on the basis of solvent‐free carbohydrate. Viscosity measurements in potassium hydroxide solutions have made possible the calculation of the viscosity‐average molecular weights. These molecular weights were found to be: Century Patna 231, 100,000; Caloro, 140,000; Rexoro, 325,000; and Zenith, 310,000. Beta‐amylase action on Century Patna and Rexoro amyloses indicated that the structures of both were similar.
Volatile Organic Acids in Pre‐ferments for Bread
Authors: HUNTER IRVING R. , NG HAWKINS , PENCE JAMES W.
Published: August 2006

An ionization‐detector gas chromatographic unit was used to analyze the acids extracted from a pre‐ferment typical of those used in commercial bread‐making. At least 45 acids were separated as esters on a column containing an adipate polyester of diethylene glycol. Seventeen of the monocarboxylic acids were identified by relative retention times in free acid form. Their identities were confirmed by preparing and separating their esters directly by flash exchange gas chromatography. The acids thus identified are: formic, acetic, propionic, isobutyric, butyric, isovaleric, valeric, crotonic, isocaproic, caproic, heptylic, caprylic, pelargonic, capric, lauric, myristic, and palmitic.
Effect of Temperature and Holding Period on Some Physical and Chemical Characteristics of Lemon Fruitsa
Authors: EAKS IRVING L.
Published: August 2006

Changes were followed in fresh weight, juice content, soluble solids, total acidity, and ascorbic acid of lemon fruits during 4, 8, and 12 weeks at 4, 13, and 24°C and after 3 and 14 days at 24°C following 4, 8, and 12 weeks at 4 and 13°C. Juice content, soluble solids, and total acidity increased during storage. The increase was greatest for fruit held at 24°C and least for fruit held at 4°C. Upon transfer to 24°C from 4 and 13°C, all three constituents increased. Changes in ascorbic acid in the lemon fruit do not appear related to the mechanism of chilling injury, but the losses observed in chilled fruit when transferred to 24°C were secondary, probably associated with symptom development.
Inhibition of the Denaturation by Salt of Myosin in Baltic Herring
Authors: LINKO R. R. , NIKKILÄ O. E.
Published: August 2006

Solubility measurements have shown that the “myosin” of Baltic herring is denatured rapidly in situ even in a 2% sodium chloride solution at 0°C. This denaturation is inhibited by various alkali phosphates and citrate. A higher concentration of sodium chloride requires a higher concentration of phosphate to prevent denaturation by the former. This action of alkali phosphates varies with the pH of the solution, probably as a consequence of changes in the net charge of the proteins and in the dissociation of the phosphates. Possible mechanisms of the inhibiting effect of the phosphates and citrates on the denaturation by sodium chloride are discussed.
Evidence for Heat Injury in Enteroccoccia
Authors: GREENBERG RICHARD A. , SILLIKER JOHN H.
Published: August 2006

The death rates of stationary‐phase brain heart infusion‐broth cultures of S. faecium and S. faecalis were independent of nitrite at 148.5±1.5°F, but were accelerated at 155±1.5°F and 158.5±1.5°F. Ascorbic acid added to the culture at the time of heating reversed the nitrite effect. Evidence was obtained for thermal injury of enterococci surviving thermal processing in a cured‐meat product. One half of the pack received a slightly longer process at 159°F than did the other. The enterococci surviving the lesser schedule eventually multiplied in the product, whereas those still viable after the lengthier process died out during storage at 50°F.
An All‐glass Laboratory Apparatus for Concentrating Volatile Compounds from Dilute Aqueous Solutions
Authors: WEURMAN C.
Published: August 2006

An all‐glass apparatus for the concentration of volatile compounds from dilute aqueous solutions on a laboratory scale is described. 3–6 L of solutions are stripped in 1 hr under reduced pressure at temperatures at or below 37°C, and concentration increases of over 10 times are obtained in a single pass. A scale drawing of the apparatus and some examples of its operation are given.
Ascorbic Acid Oxidation and Lipid Peroxidation in Milk
Authors: SMITH GRAFTON J. , DUNKLEY W. L.
Published: August 2006

Ascorbic acid oxidation was studied in relation to the natural copper level and to lipid peroxidation in milks produced by cows receiving alfalfa bay or pasture. Correlations were highly significant (r = 0.79**) between ascorbic acid oxidation rate and natural copper for both alfalfa and pasture milks. The correlation between lipid peroxidation (by the TBA test) and ascorbic acid oxidation rate was very highly significant (r = 0.87***) in alfalfa milks but nonsignificant in pasture milks.

Some postulated mechanisms for the action of copper and ascorbic acid in producing oxidized flavor were studied. The results do not support the theories of the role of the ascorbic acid radical, or of hydrogen peroxide, in the initiation of oxidized flavor.

The kinetics of ascorbic acid oxidation by light, hydrogen peroxide, and ascorbic acid oxidase were examined. Zero‐order kinetics was found for light, and first‐order for the other agents.
Some Properties of the Fibrillar Proteins of Normal and Watery Pork Muscle
Authors: BENDALL J. R. , WISMER‐PEDERSEN J.
Published: August 2006

It is shown that the washed muscle fibrils obtained from watery pork have a lower water retention at low ionic strength, and much lower extract‐ability at high ionic strength, than the fibrils from normal pork. These changes are accompanied by a gain of protein by the washed watery fibrils, and this protein originates from the soluble sarcoplasmic proteins. All the changes, including the characteristic gain of protein, can be artificially induced in normal meat by allowing it to pass into rigor at 37° C. The isoelectric region, or region of minimum swelling of watery fibrils, whether washed or unwashed, is similar to or slightly lower than that of normal fibrils. There is a broad isoelectric zone in both cases, extending from ∼pH 5 to ∼5.70. On the other hand, the IP of fully coagulated fibrils lies between 5.6 and 6.1. Washed and unwashed fibrils of watery meat show about the same degree of swelling at all pH values. Normal fibrils, however, show a higher water retention in the unwashed state than the washed. This effect is not due to the Mg or Ca ions included in the unwashed samples, but may result from interaction between the sarcoplasmic and fibrillar proteins. In the unwashed state, the swelling of normal fibrils is nearly double that of the watery fibrils at all pH values.

It is shown that the rise of pH in intact carcasses of watery meat as they cooled from 37 to 10° C was probably due to the effect of temperature on the pK of ionizable groups of the proteins and buffering substances. It can be reproduced artificially and reversibly in native and coagulated minced meat, merely by raising or lowering the temperature. The titration curves of watery fibrils show similar titration constants (pK') to those of normal fibrils, but a loss of ratable groups. Heat coagulation, on the other hand, results not only in a bigger loss of titratable groups but in a much larger shift in the titration constants. These results can be interpreted to show that the fibrillar proteins of the watery fibrils are not denatured or aggregated in the usual sense, but are probably covered by a layer of denatured sarcoplasmic protein that is firmly‐bound to the surface of the myofilaments.
Studies on the Volatile Components of Different Varieties of Cocoa Beans
Authors: BAILEY S. D. , MITCHELL D. G. , BAZINET M. L. , WEURMAN C.
Published: August 2006

Volatile compounds in the aroma of five varieties of roasted and unroasted (raw) cocoa beans have been identified by mass spectral analysis and gas chromatography. The five common varieties selected for this study all contain the following compounds usually in this order of abundance: isovaleraldehyde, isobutyraldehyde, propionaldehyde, methyl alcohol, acetaldehyde, methyl acetate, n‐butyraldehyde, and diacetyl. An additional eight compounds appear in smaller amounts. As evidenced by gas chromatographic analysis, the raw bean aroma contains the same components but in lower concentrations. The principal differences between varieties are shown to be due to the ratios of these compounds rather than new compounds. The effect of roasting period on the concentration of four aldehydes in the aroma of the ground bean is shown.
Determination of Odor Difference Thresholds
Authors: STONE H. , OUGH C. S. , PANGBORN R. M.
Published: August 2006

An olfactometer described previously was modified and used to determine odor‐difference thresholds for 48 subjects at 4 levels of 2‐heptanone. The apparatus was found to give rapid and reproducible threshold measurements. Difference thresholds were found to follow the Weber law. A Weber fraction of 0.23 mg/min/deviate was determined for 2‐heptanone. The absolute threshold was found to be 8.97 × 10−4 mg of 2‐heptanone/L air.
All‐Vegetable Protein Mixtures for Human Feeding. VIII. Biological Testing of INCAP Vegetable Mixture Nine in Ratsa,b
Authors: BRESSANI R. , ELÍAS L. G. , SCRIMSHAW N. S.
Published: August 2006

The nutritive value of INCAP Vegetable Mixture 9 in young and protein‐depleted adult rats was studied. This mixture contains 28% lime‐treated corn, 28% sorghum grain, 38% cottonseed flour, 3% kikuyu leaf meal, and 3% torula yeast. When Mixture 9, skim milk, casein, or meat flour was fed combined with different amounts of starch to give a range of dietary protein levels, the nutritive value of the vegetable mixture for rats compared favorably with that of animal proteins at the higher levels of protein intake. Both young growing rats and protein‐depleted rats were used. The growth response was generally less to the vegetable mixture at low protein levels than when animal proteins were fed at the same dietary level, presumably because of a lysine deficiency also observed in previous chick trials.

When the corn and sorghum combination was replaced in the mixture by processed corn, sorghum, rice, whole wheat, or oats, no significant changes were noted in the nutritive value. Furthermore, roasting, boiling, and lime‐treating corn and sorghum did not affect the nutritive value of the mixture.
Effect of Processing Temperature on Pigments and Color of Spinacha
Authors: TAN C. T. , FRANCIS F. J.
Published: August 2006

A method was developed for estimation of chlorophylls a and h, pheophytins a and h, lutein, and carotene in processed spinach. The method, developed primarily for calorimetric studies, involves extraction of the spinach with acetone and chromatographic separation on a sugar‐starch (70:30) column. Equations were developed for spectrophotometric estimation of the amount of each pigment in the eluate from the column. The method gave recovery values of 95–98% for a wide range of pigment mixtures, and a coefficient of variation of approximately 1.5% for reproducibility on the same extract.

Fresh spinach was blanched, pureed, packed in glass thermal‐death‐time tubes and processed in an oil bath at 240, 250, 260, 270, and 280°F for a process value equal to Fo 4.9. Color measurements indicated a difference of 4.1 units between the controls and the samples processed at 280°F, and 11.6 units between the controls and the samples processed at 240°F. The pigment changes indicated a progressively smaller change in chlorophylls a and h to pheophytins a and h as the processing temperature was raised. Chlorophyll a was degraded more rapidly than chlorophyll b, and the ratio of the two changed from 1.55 for the samples processed at 280°F, to 0.92 for the samples at 240°F. Some degradation of lutein was observed, particularly at the lower processing temperatures, whereas carotene was unchanged. The pigment‐free tissues also showed more change in color at the lower temperatures, but the contribution of the pigment‐free tissues and the degradation of lutein to the over‐all color change was very small. The major reasons for the change in color of the spinach puree upon processing were, first, the degradation of chlorophyll a to pheophytin a, and second, the degradation of chlorophyll b to pheophytin b.
Enzymatic Degradation of Collagena
Authors: HINRICHS J. R. , WHITAKER J. R.
Published: August 2006

Fiein cannot hydrolyze native collagen. Collagen can he degraded by this enzyme only after it has been denatured by heat, low pH, or high salt concentrations. This appears to he true also for the action of bromelain, papain, and trypsin on collagen.
Studies on the Kinetics of Lipoxidase Inactivation Using Thermal and Ionizing Energya
Authors: FARKAS DANIEL F. , GOLDBLITH S. A.
Published: August 2006

Lipoxidase demonstrated a typical protein inactivation response to heat as a function of pH when heated at 65°C and 0.1 molar buffer. The enzyme was found to be very sensitive to ionizing energy when irradiated in pH 7 buffer. This sensitivity was shown by a relatively low D, value (9 × 104 rad) and a rapid loss of enzyme activity during post‐irradiation storage. The results of combined treatment of the enzyme, in buffer, by heat and radiation showed that treatment order was important. Heating prior to irradiation produced inactivation proportional to the sum of the separate treatments, whereas the reverse order produced inactivation greater than that calculated from the effect of each treatment. This is in agreement with the above, where post‐irradiation storage at 0°C may be likened to a mild heat treatment. Addition of 20% pea solids to a. buffered solution of the enzyme afforded a six to ten fold protection with respect to inactivation by heat, and a seventy fold protection against inactivation by ionizing radiation. Combined heat and irradiation treatment of soybean lipoxidase, in the presence of 20% pea solids, showed that, in contrast to the results obtained in buffer, heat prior to irradiation produced greater enzyme inactivation than the reverse order of application of the two types of energy.
Stability of Spinach Catalase.
Authors: SAPERS G. M. , NICKERSON J. T. R.
Published: August 2006

Some of the variables influencing the stability of purified and unpurified spinach catalase during storage were evaluated in model systems. A purified preparation of spinach catalase was obtained from spinach leaves by comminution and extraction with phosphate buffer and extraction with n‐butanol, NH4)2SO4 precipitation, (NH4)2SO4 fractionation, dialysis, and lyophilization. The preparation had a Kat.‐f. of 3300 at pH 7.0. The stability of the enzyme in storage was influenced primarily by storage temperature, the pH of catalase solutions, and the activity of microorganisms. The enzyme concentration had a relatively minor effect on catalase stability. The stability of spinach catalase during storage was not influenced by the presence of NaCl, sucrose, starch, and denatured catalase in catalase solutions; the atmospheric pressure under which solutions were stored: or differences in freezing rates.
Stability of Spinach Catalase.
Authors: SAPERS G. M. , NICKERSON J. T. R.
Published: August 2006

The effects of certain variables on the thermal stability of spinach catalase were investigated with model systems. The rate of thermal inactivation of spinach catalase was accelerated as heating temperature was increased. Inactivation kinetics were not first‐order with solutions of the purified enzyme between 50 and 60°C and with spinach extracts at 55°C, hut became first‐order with the latter preparation as the temperature was increased to 65°C. The presence of a heat‐labile catalase inhibitor is postulated. Catalase was more thermostable in spinch extracts than in solutions of the purified enzyme. Purified spinach catalase at 55°C was more thermostable in solutions at pH 5.5 and 7.0 than at pH 9.0. The thermostahility of purified spinach catalase was not influenced by the enzyme concentration or by the presence of 1.5% NaCl, 3.6% sucrose, or 3.6% starch in pH 7.0 solution at 55°C.
Stability of Spinach Catalase.
Authors: SAPERS G. M. , NICKERSON J. T. R.
Published: August 2006

The regeneration of spinach catalase was demonstrated during storage after heat inactivation. The occurrence of regeneration was influenced by the enzyme source, pH, heating conditions, and storage conditions. The change in catalase activity after heating was considered to represent the balance between enzyme regeneration and enzyme inactivation during storage.
Pectin Methylesterase in Snap Beansa,b
Authors: VAN BUREN J. P. , MOYER J. C. , ROBINSON W. B.
Published: August 2006

Snap bean pectin methylesterase had a pH optimum of 8.2. Its activity was enhanced by the presence of salts such as sodium chloride and calcium chloride. Low pH conditions increased the susceptibility of the enzyme to heat inactivation. There were indications that conditions were present in the intact pod which protected the enzyme from heat denaturation. The enzyme had a Q10 of 1.4 over a wide temperature range. It was not regenerated on frozen storage.
Relation Between Visual Color Differences and Tristimulus Color Readings for Pureed Carrots, Spinach, and Pears
Authors: YUSON SONIA M. , FRANCIS F. J.
Published: August 2006

A range of colors for spinach, carrots, and pears was produced by blending samples of different colors and diluting with water. The samples were examined by a visual panel under a MacBeth Examolite to determine the “just noticeable color difference” (JND) and were then measured with a Colormaster differential colorimeter and a Color‐Eye calorimeter. The JND figures were 1–2.5 delta‐E units calculated by the Adams chromatic value equation. Repeatability figures on the instruments above were respectively 1/2 and 1/4 of the JND values for spinach and pears. For carrots, the repeatability and JND figures were of the same order. Repeatability figures for 4 other calorimeters were lower or approximately equal to the JND figures, indicating that several of the calorimeters could be used to determine color differences as well as an average visual panel.
Radiation Survival Curves of Clostridium Botulinum Spores
Authors: WHEATON E. , PRATT G. B.
Published: August 2006

Survival curves were obtained for massive concentrations of spores of Clostridium botulinum strain 12885A, when subjected to a wide range of gamma radiation doses under various conditions. The spore concentrations ranged from 37,000 to 64,800,000,000 per ampoule, with no recovery at 5 Mrad or more. Only at lower doses were observed survival counts compatible with classical hit theory. More than one hit is apparently required to inactivate the Cl. botulinurn spore by gamma radiation. The number of hits required for inactivation is estimated at somewhere near 13. Freeze‐dried spores exhibited less radioresistance in the dry state than when resuspended in neutral phosphate buffer. Spore suspensions in neutral phosphate buffer exhibited less radioresistance when irradiated under air than when irradiated under nitrogen. Spores exhibited less radioresistance suspended in phosphate buffer than in a nutrient medium (pork‐pea infusion). Changes in concentration of spores over a range of 37 × 103 to 53 × 109 did not significantly affect the percent survival for a given dose except in the tail area. Regardless of spore concentration, a so‐called “tailing off” of surviving spores was observed at the higher dose levels employed for varying spore concentrations. The “tailing off” phenomenon did not appear to follow the classical hit theory.
Spectrophotometric Estimation of Metmyoglobin in Frozen Meat Extractsaa
Authors: LANE J. PERRY , BRATZLER L. J.
Published: August 2006

Frozen meat‐water extracts stored under lights exhibit a pattern of metmyoglobin formation similar to that in frozen steaks. The spectrophotometric method of analysis was satisfactory for estimating the percent metmyoglobin in the solutions. Fluorescent lights significantly increased the formation of metmyoglobin in the solutions, similar to that reported for frozen steaks. Dialyzing the extract inhibited the increase of metmyoglobin in the frozen solution when stored under light. Addition of copper, manganese, or calcium ions in the form of the chloride salts to the dialyzed solution did not increase rate of metmyoglobin formation appreciably. The addition of chloride salts of magnesium and iron contributed to an increase in the rate of metmyoglobin formation. When the dialysate was concentrated and added to the dialyzed residue there was a significant increase in the rate of metmyoglobin formation.
Effect of Various Sugars on Browninga
Authors: POMERANZ Y. , JOHNSON J. A. , SHELLENBERGER J. A.
Published: August 2006

The rate of browning of 20 sugars or sugar derivatives was followed by reflectance measurements of cookies and spectrophotometric measurements of browning of dilute buffered solutions of the sugars and glycine or lysine, heated at 114°C in an autoclave. Both in cookies and in solution, the order of decreasing reactivity for the pentoses was: ribose, xylose, and arabinose. Among the hexoses, galactose was the most reactive and rhamnose the least. Because the conditions of pH and presence of amino acids were varied, no over‐all order of reactivity could be established for the other hexoses. Disaccharides with reducing groups, except melibiose, showed little reactivity. Sugars without reducing groups failed to exhibit browning.
Methionine Content of Some South Indian Foodsa
Authors: DAKSHINAMURTI K.
Published: August 2006

Methionine content of 24 of the more common foodstuffs used in South India is reported. Two independent methods were used, one based on the McCarthy and Sullivan color reaction and the other on filter‐paper disc chromatography.
Calorimetric Assay for Potassium Sorbate in Dried Fruitsa
Authors: NURY F. S. , BOLIN H. R.
Published: August 2006

A simple, direct calorimetric method requiring no distillation is described for the determination of potassium sorbate in dried fruits. The method makes use of the oxidation of sorbic acid to malonaldehyde, which reacts with thiobarbituric acid to form a red pigment that is measured photometrically.
Objective Characterization of the Mouthfeel of Gum Solutions
Authors: SZCZESNIAK ALINA SURMACKA , FARKAS ELIZABETH
Published: August 2006

A correlation was established between the mouthfeel characteristics of gum solutions and their rheological behavior. Gums that are very slimy in the mouth deviate only slightly from Newtonian viscosity. The degree of sliminess decreases with increasing deviations from the Newtonian character, and gums that exhibit a high degree of shear thinning are nonslimy in the mouth. This finding enables selection of proper gums for specific consistency effects by simple reference to the shape of the viscosity vs. the rate‐of‐shear curve.
All‐Vegetable Protein Mixtures for Human Feeding
Authors: BRESSANI RICARDO , VALIENTE ANA TERESA , TEJADA CARLOS E.
Published: August 2006

Raw and lime‐treated corn and raw and cooked beans were analyzed for nutrient content including essential amino acids. No major treatment changes were found. Eight different corn and bean combinations were tested isoproteically and isocalorically in both growing and protein‐depleted adult rats. Corn protein alone gave better results than bean protein. Replacement of part of the lime‐treated corn protein by cooked‐bean protein improved growth up to the point where each dietary component contributed 50% of the total protein of the diet (72% corn and 28% beans by weight); thereafter growth was decreased with increasing amounts of bean protein in the diet.

When the diets were supplemented with the limiting amino acids found to be deficient by comparing their amino acid pattern with that of the FAO Reference Protein, methionine proved to be the most limiting, particularly in those diets with a higher content of bean protein. The addition of lysine and methionine together improved protein efficiency further. Whenever adequate growth was obtained, higher amounts of fat were found in the liver.
Effect of Stress Prior to Slaughter on the Chemical Composition of Raw and Cooked Porka
Authors: LEWIS P. K. , BROWN C. J. , HECK M. C.
Published: August 2006

Data are presented showing that stress from periodic electric sitimulation prior to slaughter significantly affected the chemical composition and cooking losses of certain chemical components of the longissimus dorsi, psoas major, and quadriceps femoris muscles of swine.
Isolation and Description of the Pectinase‐Inhibiting Tannins of Grape Leaves
Authors: PORTER WILLIAM L. , SCHWARTZ JOSEPH H.
Published: August 2006

Studies were continued on the tannin in Muscadine grape leaves previously reported to have inhibitory activity toward peetinase and cellnlase. The tannin was isolated and purified by precipitation with caffeine and recovery by chloroform extraction. The material is a light tan, and in the freeze‐dried form is quite bulky. It is a condensed tannin of high molecular weight, producing a large percentage of phlobaphenes upon acid treatment. The soluble portion after acid treatment was shown to contain gallic acid and glucose in small amounts.
Tenderness of Beef.
Authors: COVER SYLVIA , RITCHEY S. J. , HOSTETLER ROBERT L.
Published: August 2006

This paper reports work related to scores for juiciness and two components of tenderness: softness to tongue and cheek, and softness to tooth pressure. As steak temperature increased from 61 to 80°C the meat became drier and harder, hut more markedly in biceps femoris than longissimus dorsi. From 80 to 100°C, longissimus dorsi became still drier and harder; biceps femoris also became drier but did not change in softness to tongue and cheek and became softer to tooth pressure. These changes were studied in relation to cooking times and weight losses during cooking; to percent loss of water from raw meat; and to the size and possible hydration of muscle fibers. Correlations calculated on a lot‐muscle‐temperature basis indicated that juiciness was not closely associated with any of the six components of tenderness. The closest was softness to tongue and cheek, which accounted for about 35% of the variation in biceps femoris at 80°C. The results are discussed in relation to theories of tendering or toughening.
Tenderness of Beef.
Authors: COVER SYLVIA , RITCHEY S. J. , HOSTETLER ROBERT L.
Published: August 2006

With increase in temperature (61, 80, and 100°C), scores for ease of fragmentation and lack of adhesion between muscle fibers trended toward greater toughness in longissimus dorsi (LD) and toward greater tenderness in biceps femoris (BF). Of the two muscles, RF was the more easily fragmented and had less adhesion between muscle fibers at 80 and 100°C. Mealiness was not present at 61°C, but tended to be greater at 100 than at 80°C. BF was considerably more mealy than LD. These changes in tenderness are considered in relation to chemical and histological changes during aging reported by others.
Availability of Lysine in Wholewheat Bread and in Selected Breakfast Cereal
Authors: CLARKE JUNO‐ANN KROHN , KENNEDY BARBARA M.
Published: August 2006

The protein in wholewheat unbaked bread ingredients, microwave‐baked wholewheat bread, oven‐baked wholewheat bread, and two breakfast cereals was evaluated by gain in body weight of rats, protein efficiency ratio, increase in carcass nitrogen, and apparent availability of lysine as determined by fecal excretion.

No significant differences were noted between the bread ingredients and microwave‐baked bread. Oven‐baked bread gave values significantly lower, 24–45%, than those of the ingredients. The apparent availability of lysine in bread ingredients and in microwave‐baked bread was 96% and 95%, respectively, whereas that for oven‐baked bread was 70%.

The protein in one breakfast cereal barely maintained the weight of the animals, and gave low values for protein efficiency ratio and increase in carcass nitrogen. Seventy‐five percent of the lysine was available. The other cereal allowed good growth of the animals and gave values similar to those for nonfat milk. In this oat‐and‐wheat‐germ cereal, 88% of the lysine was available.

A linear relation was obtained between either gain in body weight or increase in body nitrogen and the amount of available lysine ingested.
The Liquefying Action of Pancreatic, Cereal, Fungal, and Bacterial Alpha‐Amylasesa
Authors: POMERANZ Y.
Published: August 2006

The starch‐liquefying abilities of alpha‐amylases from pancreas, cereals, fungi, and bacteria were studied by following changes in the viscosity of potato starch pregelatinized and cooled in the Amylograph under standardized conditions and acted on by the enzyme at 37°C. The optimal pH activity for starch liquefaction was 4.0 for fungal, 4.5 for cereal, 6.5 for bacterial, and 7.0 for pancreatic amylase. A comparison of liquefying action of the enzyme systems at a constant level of dextrinogenic activity showed the pancreatic enzyme most active, followed by cereal, with the fungal least active. The relative differences between the activity of the bacterial and fungal enzymes at their optimum pH's and at 37° depended on the levels of enzyme added. The thermostable bacterial amylase also exhibited high stability toward high acidity. The pattern of starch liquefaction by action of the various enzymes, and the relation between viscosity drop and enzyme activity, are discussed.
Post‐Mortem Changes in the Muscles of Landrace Pigsa
Authors: BENDALL J. R. , HALLUND O. , WISMER‐PEDERSEN J.
Published: August 2006

A series of chemical and physical measurements were carried out on samples of the longissimus dorsi muscles from 10 Danish Landrace pigs. The samples were taken out immediately after sticking and held at 37°C. Estimations were made at intervals of the content of lactic acid, adenosine triphosphate, creatine phosphate, adenosine nucleotide, and inosine nucleotide, and of pH and extensibility, until rigor mortis was complete. The material could be divided, into two groups, A and B. Group A was characterized by a slow fall of pH (max. 0.65 units/hour) and by a slow decrease in extensibility (full rigor at 280 min), whereas group B showed a rapid fall of pH (max. 1.04 units/hour) and a rapid development of rigor (full at 160 min). There was a similarly clear difference between the rates of the other changes. Q10 for the rate of pH fall was 2.70 over the temperature range 36–41°C. The day after slaughter, all carcasses that gave samples of type A were of excellent quality, whereas those giving type B were more or less pale and watery. The differences between the two groups could not be explained by different handling of pigs before slaughter.
Factors Affecting Enzymatic Solubilization of Beef Proteins
Authors: EL‐GHARBAWI M. , WHITAKER J. R.
Published: August 2006

Investigation was made of the effect of pH, enzyme concentration, cysteine, sodium chloride, and temperature on the extent of solubilization of 0.10N sodium hydroxide‐soluble proteins, elastin, and collagen of biceps femoris muscle of beef by ficin and bromelain. All protein fractions of beef are solu‐biked maximally at pH 7 and 80°C by both ficin and bromelain. Ficin is particularly effective in the solubilization of elastin, even at 20°C. Cysteine and sodium chloride increase the extent of solubilization, especially of collagen and elastin (sodium chloride only). The available data indicate that collagen must be denatured before ficin and bromelain can solubilize it.
Estimation of Extra‐Cellular Starch of Dehydrated Potatoes
Authors: REEVE R. M.
Published: August 2006

Extra‐cellular starch is isolated from dehydrated mashed potatoes by rehydration of 0.5‐g samples with 100 ml water at 150°F. The suspension is poured over a standard 150‐mesh sieve, and the water containing the freed starch gel collected and filtered. Starch so collected on 7‐cm hardened and extremely retentive filter paper is stained with iodine, and its reflection density (Rd) and color characteristics measured on a color‐difference meter. Transmission values may also be determined. In addition, extra‐cellular starch, so collected from l‐g samples, may be dried and weighed. Rd values are a linear function of the amount of starch. The temperature of the sample suspension also has a linear effect on reflection density.

Since added stearates do not interfere with reflection density values, the effects of added emulsifiers on iodine color of the collected starch gel are measurable by color‐difference procedures. Color difference also provides a means of characterizing other starch changes, such as retrogradation, induced by processing treatments.

An insignificant number of the smallest intact cells pass through the screen to be collected on the filter paper. The intact, separated cells of cooked potato range from less than 40 to nearly 400 μ in diameter. They average about 180 μ, and over 90% have diameters between 100 and 250 μ.
Electrophoretic Separation of Beet Pigments
Authors: POWRIE W. D. , FENNEMA O.
Published: August 2006

Paper electrophoretic separation of pigments in beet extracts and in intact tissue was investigated. Pigments in an extract were separated into 9 distinct bands upon electrophoresis with 0.15M pyridine‐citric acid buffer, pH 4.5. A technique is presented for the re‐electrophoresis of pigments in paper section of an electrophoretogram. Using a Veronal buffer (pH 8.6) during re‐electro‐phoresis, heterogeneity of the pigments in major red and major yellow bands was displayed. Under specific conditions, beet pigments in a thin section of tissue could be resolved by electrophoresis.
The Protein Quality, Digestibility, and Composition of Algae, Chlorella 71105a
Authors: LUBITZ JOSEPH A.
Published: August 2006

Freeze‐dried Chlorella 71105 was found to contain 55.5% crude protein; 7.5% crude fat; 8.25% ash; 7.0% moisture; 17.8% total carbohydrate; 3.1% crude fiber; 2.68% chlorophyll; and .08% urea. The digestibility of the protein was 86%; of crude fat, 93%; of total carbohydrate, 72%; and of crude fiber, 15%. The protein efficiency ratio (PER) was 2.19, which compares favorably with soy protein. The PER of Chlorella with 0.2% L‐methionine was 2.90, which compares favorably with casein values in the literature. The PER of casein was 3.30; that of defatted egg protein, 4.01, in these studies. The rats were fed at 10% protein levels. In addition, Chlorella 71105 contained all essential amino acids as well as having a high carotene content. Available energy value was 3.3 kcal/g.
Food Crushing Sounds. An Introductory Studya,b
Authors: DRAKE BIRGER K.
Published: August 2006

The sounds produced by chewing foodstuffs, or by crushing them between flat surfaces, were tape recorded and analyzed as to amplitude, frequency, and duration. Preliminary data are given on chewing sound characteristics, including certain differences between foodstuffs.
Sexual Behaviour Induces the Expression of Activity‐Regulated Cytoskeletal Protein and Modifies Neuronal Morphology in the Female Rat Ventromedial Hypothalamus
Authors: Flanagan‐Cato L. M. , Calizo L. H. , Griffin G. D. , Lee B. J. , Whisner S. Y.
Published: August 2006

Female sexual behaviour activates a distributed network within the brain, including the ventrolateral subdivision of the hypothalamic ventromedial nucleus (vlVMH), as demonstrated by behavioural studies performed in conjunction with the neuroanatomical analysis of immediate early gene (IEG) expression. However, it has been difficult to interpret mating‐induced IEG expression because the precise function of many IEGs remains poorly defined. One possible function for genomic activation of the vlVMH during mating behaviour is to establish synaptic remodelling. The present experiments tested the hypothesis that sexual behaviour rapidly induces the expression of a structural protein associated with synaptic plasticity and ultimately causes morphological changes in the vlVMH. First, the expression of activity‐regulated cytoskeletal protein (Arc), an IEG associated with neural plasticity, was assayed immunohistochemically in females after approximately 1 h of mating. The number of Arc‐labelled neurones in the vlVMH was greater in mated females compared to unmated controls. Second, VMH neurones were biolistically labelled for morphological measurements, including soma size, dendrite number and length and dendritic spine density. Dendritic spine density in the vlVMH was significantly reduced 5 days after mating in experienced females compared to sexually naïve females. There were no differences between these groups in soma size, dendrite length or dendrite number. Collectively, these studies suggest that mating behaviour produces short‐term changes in structural proteins and long‐term, selective changes in dendrite morphology, which then may influence future behaviours and/or physiology.
Adsorption of human salivary mucin MG1 onto glow‐discharge plasma treated acrylic resin surfaces
Authors: YILDIRIM M. S. , KESIMER M. , HASIRCİ N. , KILIÇ N. , HASANREİSOĞLU U.
Published: August 2006

summary  It has been suggested that altering the surface properties of acrylic resin material may change the nature of the adsorbed pellicle affecting denture retention and microbial adherence. This study aimed at evaluating the adsorption of salivary high molecular‐weight mucins, a major component of denture pellicle, onto modified acrylic resin surfaces. (Poly) methylmethacrylate specimens were treated by glow discharge plasma technique, using hydrophilic 2‐Hydroxyethylmethacrylate monomer or oxygen (O2) gas and hydrophobic Hexamethyldisiloxane monomer, at different discharge powers. Acrylic samples were incubated with high‐molecular weight mucin, MG1 purified from saliva, the adsorbed fractions were transferred to nitrocellulose membranes by slot–blot technique, stained by periodic acid‐Schiff and colour intensities were analysed by a colour densitometer. Higher amounts of mucins were adsorbed on all the surfaces modified by glow‐discharge plasma treatment. Within the limitations of this study, it was concluded that glow‐discharge plasma altered the surfaces of acrylic resin denture base materials and significantly increased the adsorption of high molecular‐weight mucins at varying levels depending on plasma parameters.
Pharmacokinetics and enhanced PKR response in patients with chronic hepatitis C treated with pegylated interferon alpha‐2b and ribavirin
Authors: Asahina Y. , Izumi N. , Umeda N. , Hosokawa T. , Ueda K. , Doi F. , Tsuchiya K. , Nakanishi H. , Matsunaga K. , Kitamura T. , Kurosaki M. , Uchihara M. , Higaki M. , Miyake S.
Published: August 2006

Summary.  This study investigated the molecular and pharmacokinetic mechanisms of the enhanced antiviral efficacy associated with pegylated interferon (PEG‐IFN) alpha‐2b and ribavirin. The study involved comparing the expression of serial double‐stranded RNA‐activated protein kinase (PKR) before and during treatment in 26 PEG‐IFN alpha‐2b and 26 conventional IFN alpha‐2b recipients matched for age, body weight and dose of ribavirin. The pharmacokinetics of PEG‐IFN alpha‐2b and ribavirin was analysed in 15 of the 26 PEG‐IFN recipients. There was a rapid increase in PKR expression in both treatment groups, although expression from day 2 onwards was maintained at a significantly higher level in the PEG‐IFN recipients (P < 0.05). Cmax of PEG‐IFN occurred 12–48 h after the initial administration, with t1/2 and Cmin being 49 h and 190 pg/mL, respectively. In contrast to ribavirin, accumulation of PEG‐IFN was minimal. There was no association between serum PEG‐IFN and ribavirin levels and virological response. Although baseline expression of PKR before treatment was marginally higher in nonresponders (NRs), from day 2 onwards, sequential PKR expression in response to PEG‐IFN was higher in sustained viral responders compared with the NRs (P < 0.05). Significant correlations were found between kinetics of PKR expression and viral decline rates in each phase of hepatitis C virus dynamics (first phase, r = 0.67, P = 0.0006; second phase, r = 0.67, P = 0.001). In conclusion, improvement in pharmacokinetics following pegylation led to higher intracellular PKR expression, which was associated with enhanced virological efficacy of PEG‐IFN‐based combination therapy. The concentrations of both ribavirin and PEG‐IFN alpha‐2b were not associated with viral response and PKR expression.
Phylogeography and the geographic cline in the armament of a seed‐predatory weevil: effects of historical events vs. natural selection from the host plant
Authors: TOJU HIROKAZU , SOTA TEIJI
Published: August 2006

Japanese camellia (Camellia japonica) and its seed predator, the camellia weevil (Curculio camelliae), provide a notable example of a geographic mosaic of coevolution. In the species interaction, the offensive trait of the weevil (rostrum length) and the defensive trait of the plant (pericarp thickness) are involved in a geographically‐structured arms race, and these traits and selective pressures acting on the plant defence vary greatly across a geographical landscape. To further explore the geographical structure of this interspecific interaction, we tested whether the geographical variation in the weevil rostrum over an 800‐km range along latitude is attributed to local natural selection or constrained by historical (phylogeographical) events of local populations. Phylogeographical analyses of the mitochondrial DNA sequences of the camellia weevil revealed that this species has experienced differentiation into two regions, with a population bottleneck and subsequent range and/or population expansion within each region. Although these phylogeographical factors have affected the variation in rostrum length, analyses of competing factors for the geographical variation revealed that this pattern is primarily determined by the defensive trait of the host plant rather than by the effects of historical events of populations and a climatic factor (annual mean temperature). Thus, our study suggests the overwhelming strength of coevolutionary selection against the effect of historical events, which may have limited local adaptation.