bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical and Physical Development of the Pineapple Fruit III. Nitrogenous and Enzyme Constituents
Authors: GORTNER WILLIS A. , SINGLETON VERNON L. 
Published: August 2006

SUMMARYNitrogenous constituents of developing pineapple fruit were determined at weekly intervals on two lots of fruit in 1958 and four lots in 1963. Some analyses on shell tissue were included. The fraction of nitrogen in the flesh of the fruit not precipitated by trichloroacetic acid or by heating fell during the prematuration period, then rose during the final weeks of development. By contrast, the concentration of heat‐soluble nitrogen in the shell fell throughout fruit development. Many of the constituent free amino acids in the juice also showed a minimum concentration during the middle of the developmental period, or maturation. The notable exception to the nitrogen trends was methionine, which was generally absent until onset of final ripening but present in considerable amounts thereafter. Protein concentration rose during the first weeks after cessation of flowering, then dropped somewhat during the remainder of fruit development. Little or no protease activity was found in the flesh of fruit shortly after flowering, but the enzyme then appeared abruptly and remained at a high level during fruit development, dropping only during the final period of ripening. Peroxidase activity was high in the young fruit and fell steadily throughout fruit development, reaching a minimum during ripening. At this time, the activity was only a third that of the fruit shortly after flowering. The trends in nitrogenous constituents reinforced the earlier suggestion of several discrete physiological stages in the development of the pineapple fruit.
Chemical and Physical Development of the Pineapple Fruit IV. Plant Pigment Constituents
Authors: GORTNER WILLIS A. 
Published: August 2006

SUMMARYPigments in the shell and flesh tissues of developing pineapple fruit were analyzed at weekly intervals on four different lots of fruit ripening in the spring and in the summer of 1963. Chlorophyll in the shell showed little change until final ripening began. It then disappeared during the final two weeks of development. Anthocyanin and chalcone compounds in the shell fell off steadily throughout fruit development. The carotenoid pigments in the shell showed a small downward trend during development, followed by a small rise during senescence of the fruit, after the chlorophyll had disappeared. In the flesh, however, the carotenoids showed quite marked changes. These pigments fell until about seven weeks before ripeness, then rose markedly during the final two‐week ripening period. The trends in plant pigments are consistent with suggestions from earlier studies on nitrogenous, carbohydrate, and acid constituents of the pineapple during development, indicating that there are several discrete physiological stages for the fruit.
Apple Leucoanthocyanins
Authors: ITO SABURO , JOSLYN M. A. 
Published: August 2006

SUMMARYThe leucoanthocyanins present in the peel and flesh of Gravenstein apple were extracted with methanol and fractionated. Five preparations were obtained from apple peel, and three from apple flesh. These were characterized on the basis of solubility, mobility on paper, astringency and nature of products yielded on heating with dilute and concentrated hydrochloric acid solutions. On mild acid hydrolysis both the peel and flesh leucoanthocyanins yielded catechin and epicatechin. On stronger acid hydrolysis these yielded cyanidin and pelargonidin. Absorption spectra were obtained in the visible, ultraviolet, and infrared regions. The major apple leucoanthocyanins were found to be highly polymerized and quite complex.
Quantitative Changes in Date Polyphenols and Their Relation to Browning
Authors: MAIER V. P. , METZLER D. M. 
Published: August 2006

SUMMARYSimple polyphenols in dates decrease during growth, maturation, and storage, whereas soluble leucoanthocyanidin tannins increase during growth and are converted to insoluble leucoanthocyanidin tannins during maturation. Insoluble tannins increase during growth and maturation and decrease during storage. Various tests indicate that the insoluble tannins take part in a nonenzymic oxidative browning reaction in dates.
Sulfur Dioxide Inhibition of Anthocyanin Degradation by Phenolasea
Authors: GOODMAN L. P. , MARKAKIS P. 
Published: August 2006

SUMMARYThe degradation of cyanidin 3‐gentiobioside by mushroom phenolase in a model system containing catechol is inhibited by SO2. In a citrate phosphate buffer, pH 6.5, with 2.8 × 10−5M catechol and 3.3 mg commercial enzyme per 100 ml reaction mixture, 8 ppm of SO2 completely checked the anthocyanin degradation. In tart cherry juice, under similar conditions but with no catechol added, 30 ppm SO2 were required for a practically complete inhibition. At lower pH the inhibition is accomplished by smaller SO2 concentrations.
Changes in Chicken Muscle Proteins During Cooking and Subsequent Frozen Storage, and Their Significance in Quality
Authors: KHAN A. W. , VAN DEN BERG L. 
Published: August 2006

SUMMARYCooking of chicken broilers destroyed the proteolytic activity and the buffer extractability of muscle proteins, and decreased the sulfhydryl‐group content of muscle proteins by about 50%. During frozen storage of cooked meat for two years at temperatures between −10 and −40°C, neither the formation of protein‐breakdown products nor the development of detectable off‐odor occurred. The sulfhydryl‐group content of muscle tissue decreased gradually, showing a relation with storage time and loss of tenderness. Results suggest that the color reaction between the sulfhydryl groups of muscle tissue and nitroprusside may be useful as an index of quality changes in precooked frozen poultry.
The Composition of Essential and Certain Nonessential Amino Acids in Selected Hawaii Fish
Authors: CABBAT FELICITAS SAMBAJON , STANDAL BLUEBELL R. 
Published: August 2006

SUMMARYEssential amino acids were determined by column chromatography for 5 varieties of fish popular as food in Hawaii. Recoveries for the amino acids studied were good, ranging from 98.7 to 102.2%. The content of essential as well as certain nonessential amino. acids was uniform for all the fish investigated, and the values of valine were higher than cited by other authors. There was no marked difference in the essential amino acid composition of the octopus and the four vertebrates. The proportions of the essential amino acids were compared with the proportions in the FAO “Provisional Pattern” and whole egg protein, and the protein scores were calculated. Favorable comparisons were obtained with the FAO pattern. Leucine and phenylalanine were somewhat limiting for all fish when compared with whole egg protein. The content of nonessential amino acids (histidine, glycine, glutamic acid, alanine, and proline) was comparable with ranges reported for other fish.
Cross‐Sectional Tenderness Variations Among Six Locations of Pork Longissimus Dorsi
Authors: ALSMEYER R. H. , THORNTON J. W. , HINER R. L. 
Published: August 2006

SUMMARYCertain cross‐sectional variations in tenderness were studied among 97 pork loin roasts by panel, Warner‐Bratzler shear, and the slice tenderness evaluator (STE). This instrument, used with a universal testing machine and load cell, first punctures and then shears off circular meat wafers 3/8‐inch in diameter. Longissimus dorsi (loin‐eye) slices from heated roasts were graphically partitioned into six locations (two each from the dorsal, medial, and lateral areas) and resistances to STE puncture and shear were recorded. The lateral locations were the most tender, and medial locations the least tender. Correlation of panel scores with STE values was greatest for the toughest areas. Simple correlations between STE values and panel score were highly significant, with stronger relationships being noted between panel and STE shear. The noticeable difference in tenderness observed among the six pork loin‐eye locations emphasizes the importance of careful and consistent sampling methods.
Water Activity of Flour at High Moisture Contents as Measured with a Pressure Membrane Cell
Authors: GUR‐ARIEH C. , NELSON A. I. , STEINBERG M. P. , WEI L. S. 
Published: August 2006

SUMMARYA method was developed for the determination of water activities of flour at high moisture contents. In this method a flour sample was allowed to equilibrate with water contained in a porous membrane while under a certain constant mechanical pressure. The cell was fitted with a porous membrane which allowed the transfer. of moisture from and to the sample. After equilibrium was achieved the sample was analyzed for moisture content. A thermodynamic relationship enabled calculation of the water activity corresponding to the pressure used in the cell. Results obtained with this method were in agreement with those obtained with the constant‐relative‐humidity desiccator technique in the over‐lapping range of water activities. The two methods were also in agreement that the water activity of flour was not affected by the particle size distribution.
Volatile Components of Tomatoes
Authors: PYNE A. W. , WICK E. L. 
Published: August 2006

SUMMARYMethods were developed for the preparation in reproducible yield (2–5 ppm) of odor concentrate from fresh ripe tomatoes. Sufficient concentrate was obtained to allow its separation by gas chromatography and collection of its components for direct investigation. Examination of the fractions resulted in rigorous identification of previously unknown tomato constituents.
The Influence of Ante‐Mortem Factors and Gamma Irradiation on the ‐Degradation of 5′‐Ribonucleotides in the Muscle f English Sole (Parophrys vetulus)
Authors: GUARDIA ENRIQUE J. , DOLLAR ALEXANDER M. 
Published: August 2006

SUMMARYThe influence of feeding, activity and pasteurizing doses of gamma irradiation on the nucleotide composition and breakdown in English sole (Parophrys vetulus) was studied. Feeding did not cause any significant change in the total amount of nucleotides. Active fish had lower amounts of ATP and increased levels of IMP, but this difference was not significant after they had been stored 7 days in ice. In contrast to the results reported for other species of sole, inosine was present in English sole after 7 days in ice. Irradiation, 0.5 and 1.0 Mrad, did not affect the changes in the nucleoside and nucleotide composition.
The Fatty Acid Composition of Free and Bound Lipids in Freeze‐Dried Meats
Authors: GIAM I. , DUGAN L. R. 
Published: August 2006

SUMMARYThe fatty acid composition of free and bound lipids in freeze‐dried pork, lamb, and beef was determined by gas‐liquid chromatography (GLC). Both raw and cooked samples were studied to establish whether cooking affected the fatty acid content of either fraction. Sixteen acids were identified in pork, lamb, and beef. In the bound lipids fraction, traces of saturated C13, C15, and C17 were evident. Three peaks remained unidentified. These unknown peaks are probably unsaturated acids, although the possibility that they may be oxidation products cannot be ruled out entirely. The bound lipids fraction of the meat samples studied was found to have a greater quantity of polyunsaturated fatty acids than the free lipids fraction. The linoleic, behenic, and arachidonic acid content of the bound lipids exceeded that of the free lipids fraction. Cooking prior to freeze‐drying appeared to have no significant influence on the fatty acid composition of either free or bound lipids. Lamb and beef are similar to each other in fatty acid composition, and quite different from pork. The myristic and myristoleic acid content is higher in lamb and beef than in pork, but the linoleic and arachidonic acid content of pork exceeds that of lamb and beef.
Purification and Certain Properties of Avocado Polygalacturonase
Authors: REYMOND DOMINIQUE , PHAFF H. J. 
Published: August 2006

SUMMARYA procedure was developed for the extraction of polygalacturonase (PC) from avocado mesocarp. PG, which is absent from immature fruit, begins to develop at the blossom end and progresses toward the stem end. By ammonium sulfate fractionation, ion‐exchange chromatography, and the use of calcium phosphate gel, a four‐step procedure was developed resulting in a 36‐fold purification in terms of specific activity. Avocado PG causes a random hydrolysis of polygalacturonic acid to D‐galacturonic acid; it has an optimum pH of 5.5 in sodium acetate buffer. Partial inhibition was caused by ammonium, potassium, and phosphate ions, and inhibition was nearly complete by polymeta‐phosphate. Evidence is presented for the presence of a natural inhibitor of avocado PG in mesocarp tissue.
Volatile Flavor and Aroma Components of Pineapple. l. Isolation and Tentative Identification of 2,5‐Dimethyl‐4‐Hydroxy‐3(2H)‐Furanone
Authors: RODIN J. O. , HIMEL CHESTER M. , SILVERSTEIN ROBERT M. , LEEPER ROBERT W. , GORTNER WILLIS A. 
Published: August 2006

SUMMARYAn unstable compound with an intense odor of “burnt pineapple” was isolated as a major component of a pineapple flavor concentrate. This compound was tentatively identified as 2,5‐dimethyl‐P‐hydroxy‐3(2H)‐furanone (I).
The Anthocyanin Pigments of Boysenberries
Authors: LUH B. S. , STACHOWICZ K. , HSIA C. L. 
Published: August 2006

SUMMARYAnthocyanins in boysenberries were extracted and purified by ion‐exchange and paper chromatographic methods. The pigments were identified by R1 values, sugar moiety, alkaline degradation products of the aglycone, partial acid hydrolysis, and absorption spectra. The major pigments were shown to be cyanidin 3‐mono‐glucoside and cyanidin 3‐diglucoside. Also present were smaller amounts of cyanidin 3‐rhamnoglucoside and cyanidin 3‐rhamnoglucosido‐5‐glucoside.
Control of Protein Level of Algae, Chlorella
Authors: TAUB FRIEDA B. , DOLLAR A. M. 
Published: August 2006

SUMMARY Chlorella pyrenoidosa No. 71105, grown under limited nitrate conditions (1mM NO‐s) had protein levels of 21–6470 of the total dry weight when grown in continuous culture, and only 5–20% protein when grown as stationary cultures. Light limited both the protein fixation and the total production of dry algal tissue. Protein per liter increased with light, but at a slower rate than total dry weight, resulting in yields of greater protein per liter but cells of lower percentage of protein. Up to limiting concentrations of nitrate the algal yield (dry matter) was directly proportional to light received. The conversion of light energy to net chemical energy was between 3 and 13%.
Analysis of the Terpene and Sesquiterpene Hydrocarbons in Some Citrus Oils
Authors: HUNTER G. L. K. , BROGDEN W. B. 
Published: August 2006

SUMMARYThe terpene and sesquiterpene hydrocarbons in various citrus essential oils are analyzed in a two‐step procedure. During the first step, the oxygen‐containing compounds are removed by column chromatography. In the second step, the terpenoid‐free oil is analyzed by gas chromatography, using a small sample to obtain the terpene analysis and a larger sample to obtain the sesquiterpene analysis. It was found expedient to increase the temperature during the analysis to shorten the sesquiterpene elution time. This method has been applied to different types of orange and grapefruit oils, also to tangerine, lemon, and lime oils. It is now possible to obtain a rapid evaluation of the hydrocarbons in these essential oils. A semi‐quantitative relationship between the hydrocarbons in the individual oils and between various oils can be obtained directly from the chromatograms. The identity of the constituents was determined by infrared and mass spectroseopy, and the wide compositional variations between the oils are discussed.
Isolation and Identification of Volatile Components from High‐Temperature‐Cured Off‐Flavor Peanuts
Authors: PATTEE H. E. , BEASLEY E. O. , SINGLETON J. A. 
Published: August 2006

SUMMARYThis paper describes isolation, separation, and partial identification of 21 volatile components from high‐temperature‐cured off‐flavor peanuts. Isolation was accomplished by vacuum distillation. Separation was achieved by gas chromatography, using diisodecylphthlate and polyethylene glycol 600. Identification was based upon relative retention volumes on the two columns used and functional group analysis. Eleven of the 21 compounds were identified: formaldehyde, acetaldehyde, ethanol, acetone isobutyraldehyde, ethyl acetate, butyraldehyde, isovaleraldehyde, 2‐methyl valeraldehyde, methyl butyl ketone and hexaldehyde. Three others were partially identified.
Free Amino Acid Content of Chicken Muscle from Broilers and Hens
Authors: MILLER JULIUS H. , DAWSON L. E. , BAUER DORIS H. 
Published: August 2006

SUMMARYFree amino acid analyses were conducted on 24 muscle tissue samples of chicken, both young and old, fresh and aged, in an attempt to show some properties or constituents of the meat which might he related to quality factors, such as tenderness. In general, ammonia nitrogen remained fairly constant throughout the study. Storage resulted in increases in free amino acids, with proline being a major exception. Light meat showed less free amino acids than dark meat, with major exceptions being lysine and histidine. In most cases, broilers had more free amino acids than hens. Taurine concentration was much higher in the dark meat of both broilers and hens. No relation was found between tenderness and the general pattern of free amino acid concentration or between tenderness and the concentration of any single free amino acid.
The Effect of Boron on the Lipid Content and Discoloration of Potatoes
Authors: MONDY N. I. , BOURQUE A. , BRESLOW B. , MATTICK L. R. 
Published: August 2006

SUMMARYOntario, Katahdin, and Pontiac potatoes grown with and without boron foliar spray were examined for discoloration and lipid content. The lipid was fractionated into free fatty acids, neutral fat, and phospholipids. The free fatty acids from each of the three fractions were esterified and determined quantitatively by gas chromatography. Discoloration was measured with a Hunter color‐difference meter.The total lipid of all three varieties was higher in potatoes treated with boron than in the control potatoes. Cortex tissue was significantly higher in lipid content that center tissue. Pontiac potatoes, the variety most resistant to discoloration, had the highest lipid content. The phospholipid fraction of all three varieties was higher in the potatoes treated with boron, and the neutral‐fat fraction was higher in Pontiac potatoes treated with boron than in untreated potatoes.Treatment of potatoes with boron tended to increase the amount of unsaturated and decrease the amount of saturated fatty acids. The free fatty acid fractions of potatoes receiving boron treatment were lower in palmitic and higher in linoleic acid than the control, the neutral fat fraction was higher in linolenic acid, and the phospholipid fraction was lower in palmitic acid. Potatoes receiving boron discolored less than control potatoes.
The Ionization Behavior of Some Poly (Meta) Phosphates Used in Food Products
Authors: BATRA S. C. 
Published: August 2006

SUMMARYThe degree of ionization of some sodium polyphosphates used in the food industry was determined with sodium ion electrodes. The effect of the presence of the calcium ion on the ionization of these phosphates was also studied. Sodium orthophosphate completely dissociated in solution, with the degree of dissociation of the polyphosphates inversely proportional to the number of P atoms in the chain or the ring. The addition of calcium enhanced the dissociation of the polyphosphate and lowered the pH in each case.
Studies on the Gelatinization of Starch I. Competition for water by protein and cellulose derivatives
Authors: WATSON C. A. , JOHNSON JOHN A. 
Published: August 2006

SUMMARYSome effects of egg albumen, gelatin, methyl cellulose c(MC) and carboxymethyl cellulose (CMC) on the gelatinization of unmodified corn and waxy maize starches are reported. The effect of increasing concentrations of those four substances on gelatinization of the starch was determined at 70, 80, and 100°C, and with 40, 60, and 80% moisture. The main criterion for the amount of gelatinization was the susceptibility of the starch to beta‐amylase.Albumen, at the higher concentrations employed, inhibited gelatinization of the starches heated at 70°C with 60 and 80% moisture but did not affect degree of gelatinization at higher moisture levels or at higher temperatures. Gelatin inhibited gelatinization of the starches heated at 70°C more than did albumen, and inhibited to some degree the gelatinization of starches heated to 80°C with 60% moisture. At higher moisture levels and temperatures, gelatin had no effect on extent of starch gelatinization. Methyl cellulose significantly affected starch gelatinization at 70°C but had less and no effect at 80 and 100°C, respectively. Carboxymethyl cellulose had pronounced effect on starch gelatinization at all temperatures and moisture levels except the 80% moisture level system heated at 100°C.In bread dough containing between 36 to 38% moisture, starch gelatinization increased with temperature in the center of the loaf. The rate of increase of starch gelatinization was less than the rate of increase of temperature during baking.
A Comparison of Glycolysis and Associated Changes in Light and Dark Portions of the Porcine Semitendinosus
Authors: BEECHER G. R. , BRISKEY E. J. , HOEKSTRA W. G. 
Published: August 2006

SUMMARYPost‐mortem glycolysis and related properties in light and dark portions of porcine semitendinosus were studied to determine differences in composition as well as rate and extent of change at two post‐mortem holding temperatures. These post‐mortem changes in the light and dark portions of the semitendinosus were studied in animals evidencing a death reaction, after insensibilization by a captive‐bolt pistol, as well as in animals which were insensibilized by sodium pento‐barbital which yielded no evident death reaction. Dark‐muscle portions contained higher initial values for pH and glycogen and exhibited a shorter delay phase of rigor mortis. Lowering the post‐mortem holding temperatures from 37 to 4°C slowed post‐mortem glycolysis and increased the water‐binding capacity in both muscle portions. Lactic acid concentrations (24 hr) in both portions were similar at both post‐mortem holding temperatures. Insensibilization with sodium pento‐barbital slowed post‐mortem glyeolysis but increased the accumulation of lactic acid in both portions. The delay phase of rigor mortis from animals injected with sodium pento‐barbital was lengthened more in the light portions than in the dark portions. These studies indicate that only light muscle portions have an increased glycolytic rate which may be attributable to the struggle associated with the death reaction upon insensibilization with a captive‐bolt pistol.