bluuebunny/crossref_metadata_2025 huggingface dataset:
Measure of Shear and Compression Components of Puncture Tests
Authors: BOURNE M. C.
Published: August 2006

A study was designed to separate and measure the compression components (proportional to area) and the shear components (proportional to perimeter) of a simple puncture test. Two sets of punches were used (one with a constant area and a variable perimeter, and the other with a constant perimeter and a variable area) to measure the compression and shear components in puncture tests on foam plastic board and representative foods. The puncture force for both can be expressed by the equation F = K,P + K,A + C, where K., K, and C are constants, P is the perimeter of the punch, and A is the area of the punch. K, represents the shear coefficient and Kc the compression coefficient of the food being tested. For a given punch, F depends upon K, and K, which are properties of the material being tested. For a given material, F depends on the perimeter and area of the punch. These results can be used as a basis for design of punch shape and size in a practical puncture test. The shear component of a puncture test can be increased or decreased relative to the compression component by manipulating the perimeter/ area ratio of the punch.
Changes in the Concentration of Lactic Acid and Free Sugars in Post‐Mortem Samples of Beef and Pork Muscle
Authors: GUNTHER H. , SCHWEIGER A.
Published: August 2006

Investigations were carried out on changes of lactate concentration and pH values at various post‐mortem times on different samples of beef and pork muscles (Expts. A and B). The differences in lactate concentrations between the method of Barker and Summerson and the enzymatic assay were considerable, fully confirming previous findings. Besides the lactate and pH values, glucose, fructose, maltose, and ribose were determined after feeding sucrose to some of the animals (Expt. C). Sucrose feeding decreased the pH values and increased the values for lactate in investigated muscles of exhausted animals which had been transported over 340 miles in approximately 24 hr. By this procedure some characteristics of the quality of the meat could he improved. Similar effects were not detected in animals transported only 3.1 miles, although glucose and fructose were present in significantly higher amounts in the sucrose‐fed animals than in the control group.
Relation of Pectic and Fatty Acid Changes to Respiration Rate During Ripening of Avocado Fruits
Authors: DOLENDO A. L. , LUH B. S. , PRATT H. K.
Published: August 2006

The ripening of a lot of hard mature avocado fruits (Persea americana Miller, CW. MacArthur) was followed at 15°C by measuring respiration rate and softening. The climacteric rise in respiration was accompanied by rapid softening of the flesh, a drop in content of protopectin and in degree of pectin esterification, and a rise in soluble pectin. Eight fatty acids were identified in the oil, but the oil composition did not change significantly, suggesting that the storage oil of the tissue has no major metabolic role in fruit ripening.
Quantitative Aspects of the Interaction of Carrageenan and Other Hydrocolloids with Polyvalent Cobalt Complexes
Authors: GRAHAM HORACE D. , WILLIAMS JOSEPH LEE
Published: August 2006

Carrageenan, other sulfated polysaccharides, and carboxylic acid polysaccharides react with hexol nitrate, hexamine cobaltic chloride, and tris‐(ethylenediamine) ‐cobalt III chloride in aqueous solution to give precipitates which exhibit differential solubilities in solutions of simple salts. The turbidity (optical density) produced when the hydrocolloids are mixed with these cobalt complexes is proportional to the amount of hydrocolloid present. Salts inhibit the reaction, and, generally, the order of inhibition is: monovalent cations < divalent cations < trivalent cations.

The temperature and pH of the reaction medium greatly influence the final turbidity developed. Generally, the complexes formed through the reaction of the sulfated polysaccharides and the cobalt complexes are less readily dissolved by solutions of simple salts than those formed by the carboxylic polysaccharides and the cobalt complexes. Neutral polysaccharides are not precipitated by the cobalt complexes, hence three component systems containing a sulfated, a carboxylic, and a neutral polysaccharide can be resolved and the individual components determined quantitatively. Good resolution was obtained with a mixture such as carrageenan (sulfated) plus algin (carboxylic) plus locust bean gum (neutral).

Quantitative assay of those polysaccharides which form precipitates (turbidity) with the complexes can be done either by measuring the turbidity developed or by determining spectrophotometrically the amount of cobalt complex cation bound. These colored complexes have sharp absorption maxima: hexol nitrate, max = 490 mμ; hexaminecobalt chloride, max = 475 mμ; and tris‐(ethylenediamine)‐cobalt III chloride, max = 470 mμ.
Stress‐Strain and Creep Relationships of Pectin Gels
Authors: WATSON E. L.
Published: August 2006

The rheological properties of sugar‐acid‐pectin gels were studied by measuring the stress‐strain relationships under three types of loading (impact, compression, and static). These gels are viscoelastic. When the applied stress was less than 25 lb per sq in., a permanent deformation (“plastic flow”) was observed, while with larger stress, the gel responded elastically and failure was “brittle.” Roth these responses were highly time‐dependent. The data obtained indicate that the impact and compression method of testing cannot clearly identify small differences in chemical composition. Creep tests indicate, however, that disaccharide gels supported larger stresses for longer times than did gels containing monosaccharides.
Reactivities of Lipid Solvents with Thiobarbituric Acid
Authors: HO SU YONG , BROWN W. DUANE
Published: August 2006

Methyl alcohol, ethyl alcohol, chloroform, diethyl ether, petroleum ether, cyclohexane, and carbon tetrachloride were tested for reactivity with thiobarbituric acid. Pigments with absorption maxima at 450 and 532 mμ were readily formed from petroleum ether and diethyl ether; methyl alcohol, ethyl alcohol, chloroform, and hexane reacted, but to a lesser extent; carbon tetrachloride was unreactive. The production of these malonaldehyde‐like compounds, presumably from contaminants in the solvents, was increased by heating.
Techniques for Collecting Volatile Components from Haddock Flesh for Gas Chromatographic Analysis
Authors: MENDELSOHN JOSEPH M. , STEINBERG MAYNARD A. , MERRITT CHARLES
Published: August 2006

The volatile compounds isolated from haddock (Melanogrammus aeglefinus) flesh were analyzed by cryogenic gas chromatography. Four methods of collecting the volatile compounds were studied and evaluated. Chromatograms showed that the best samples were obtained from the equilibrium vapor above the total condensate removed from the haddock flesh by vacuum distillation. Chromatograms illustrate the changes in the relative amounts of volatile compounds collected from samples of both raw and cooked fish after storage at 2°C for 1, 5, and 10 days. The amount and number of volatile compounds increased during storage, and cooking released additional compounds, some in large amount.
The Relation of Structure to Antioxidant Activity of Quercetin and Some of Its Derivatives II. Secondary (Metal‐Complexing) Activity
Authors: LETAN A.
Published: August 2006

The secondary (metal‐complexing) activity of quercetin and some of its derivatives was studied with the conventional Warburg technique in an ascorbic acid system catalyzed with cupric ions.

The 3‐hydroxy‐4‐keto group was the most powerful metalcomplexing group in the quercetin molecule; the 5‐hydroxy‐4‐keto group had some activity, but was considerably weaker. The 3′,4′‐o‐diphenolic group, important for the primary antioxidant activity, possessed virtually no metal‐deactivating properties.

Methylation of the 4′‐ or 7‐hydroxyl (or, to a lesser degree, of the 3′‐hydroxyl) increased the complexing capacity of the 0‐methylated derivative of quercetin, while hydrogenation of the 2,3 double bond yielded an almost completely inactive compound (dihydroquercetin).
Causes of Can Swelling and Blackening of Canned Baby Clams I. Chemical Factors Involved in Blackening
Authors: TANIKAWA EHCHI , MOTOHIRO TERUSHIGE , AKIBA MINORU
Published: August 2006

Hydrogen sulfide is formed from the meat of baby clams during canning. The amounts of hydrogen sulfide are usually below 50 mg%, which may be the minimum amount necessary to cause blackening. When hydrogen sulfide is produced in amounts more than 50 mg% (e.g. when the raw material is not fresh), blackening may be accelerated, or the canned baby clams may decompose and hydrogen sulfide concentration increase slightly during storage. The blackening is caused by the formation of copper sulfide and iron sulfide. Iron transferred to the intestine from the mud where the clams live, is involved in blackening. Also implicated is copper freed from hemocyanin in baby clam by boiling. Some phosphate compounds (0.270) are effective in decreasing the blackening.
Effect of Temperature and pH on the Soluble Proteins of Ham
Authors: TRAUTMAN J. C.
Published: August 2006

A sensitive heat gelling test based upon the least protein concentration as the endpoint (LCE) was developed for salt‐soluble protein evaluation in extracted muscle. Although this is not readily applicable to quality‐control procedures, it appears to be an excellent research tool to study subtle protein changes occurring in muscle proteins during the post‐mortem transformation of muscle into meat. Using the LCE to study the effect of simulated physiological temperature and pH on muscle protein extracts it was found that pH has a profound and partially, but not complete, reversible effect on these proteins. A definite relation was found between post‐rigor muscle pH and the LCE of the extracted salt‐soluble proteins, which suggests that the rigor mortis transformation of muscle to meat determines the subsequent characteristics of these proteins. The most desirable post‐rigor muscle pH was 5.8‐6.1. No mechanism is proposed to explain the effect of pH on the salt‐soluble protein LCE. The effect of decreasing pH was linear on the solubility of both water‐ and salt‐soluble proteins, and on the increase of free heme with concomitant decrease in oxymyoglobin visual color. Mixing salt‐soluble proteins from extreme‐pH post‐rigor muscle resulted in an improved LCE while averaging the solution pH and ATP(ase) activity. This mixing effect may account for the lack of relation between sausage batter variation and product quality.
Immunofluorescent Detection of Staphylococcal Enterotoxin B I. Detection in Culture Media
Authors: GENIGEORGIS C. , SADLER W. W.
Published: August 2006

Application of the fluorescent antibody technique (FAT) to detection of staphylococcal enterotoxin B and of the cells that produce it in culture media was investigated. Enterotoxin B was detected by FAT in culture media both in the presence and in the absence of bacterial cells. Two methods of detection were developed. The first involved staining of fixed smears with fluorescein‐isothiocyanate‐conjugated anti‐enterotoxin B serum. The second technique involved the precipitation of enterotoxin by mixing one drop of fluid containing either living cells and toxin or only toxin with two drops of serially diluted conjugate. After incubation, the formed precipitates were caught on Millipore filter membranes and washed, and impression smears were made on slides. Enterotoxin B was demonstrated with the first technique only when there was a minimum of 15 fig/ml. The second technique detected as little as 1 fig toxin/m1.
Lipid Hydrolysis in Unblanched Frozen Peas (Pisum sativum)
Authors: BENGTSSON B. , BOSUND I.
Published: August 2006

Data on hydrolytic changes in the lipids of unblanched (enzymatically active) peas in the range –5 to –20°C are presented. The Q10 value for the formation of free fatty acids between these temperatures is about 2.5. The corresponding value for development of off‐flavor is about 3.0. Both values are considerably lower than those typical for deteriorative non‐enzymatic reactions in blanched vegetables.

Gas chromatographic analysis of the free fatty acid fraction demonstrates further that there is an apparent preference for hydrolysis of polyunsaturated acids. This tendency is especially evident in the lower part of the temperature range studied. A corresponding increase of the proportion of saturated acids in the unhydrolyzed fat can be shown. No net change of any single acid in the combined lipid fractions is observed, except for linoleic and linolenic acids, which decrease somewhat after long storage at the higher temperatures. This indicates a substantial breakdown into smaller molecules.
Acrylamide Gel Disc Electrophoretic Patterns and Extractability of Chicken Breast Muscle Proteins During Post‐Mortem Aging
Authors: MAIER GILBERT E. , FISCHER ROBERT L.
Published: August 2006

Acrylamide gel disc electrophoretic patterns of water‐soluble extracts consistently showed the presence of 2–4 fast‐moving, faint components which increased in relative intensity with post‐mortem aging. The electrophoretic patterns of salt‐soluble and urea‐soluble extracts showed no corresponding pattern changes. The extractability of unbuffered water‐soluble proteins was less at 24 hr postmortem than at 30 min post‐mortem in breast muscle obtained from seven 7–10‐week‐old chickens. The percentage of dialyzable pep‐tides in the water‐soluble extracts and the percentages of salt‐soluble and urea‐soluble proteins in those extracts remained fairly constant during a 24hr post‐mortem aging period.
Changes in Color and other Characteristics of Green Beans Stored in Controlled Refrigerated Atmospheres
Authors: GROESCHEL E. C. , NELSON A. I. , STEINBERG M. P.
Published: August 2006

The value of controlled atmosphere for holding of green beans prior to marketing or processing was studied. Respiration rates and color changes were studied in bottles under atmospheres ranging from 0 to 10% CO2 and 2 to 20% O2. The bottles were flushed periodically. Other studies involved storing green beans at 45°F up to 15 days in a 10% CO2 and 3% O2 atmosphere continuously produced by a generator and in air. The tests used to evaluate product included visual color and chlorophyll determinations; organoleptic evaluation; plate counts; pH measurements and nitrogen analyses.

Oxygen concentration had to he reduced to 2% to decrease respiration to 60% of that in air, while carbon dioxide had little or no effect on respiration. The greatest advantage of con‐trolled‐atmosphere storage for beans lies in improving the color of stored product by retarding chlorophyll breakdown.

Flavor and texture scores and microbiological studies showed no differences between con‐trolled‐atmosphere and air storage.
Anthocyanins of the Garden Huckleberry, Solanum guineese
Authors: FRANCIS F. J. , HARBORNE J. B.
Published: August 2006

The anthocyanin pigments of the garden huckleberry (Solanum guineese) were isolated and identified from their chromatographic, spectral and chemical properties. The major pigment was petanin (petnnidin‐3 (p‐coumaroyl rutinoside)‐5‐glucoside) (93%). The minor pigments were petunidin‐3‐rutinoside‐5‐glucoside (3.5ys), negretein (malvidin‐3 (p‐coumaroyl rutinoside)‐5‐glucoside (2.0%), and a new compound, guineesin, petunidin‐3‐rutinoside‐5‐glucoside acylated with two molecules of p‐coumaric acid (1.5%).
Pressure Losses and Rheological Properties of Flowing Butter
Authors: HANCK R. C. , HALL C. W. , HEDRICK T. I.
Published: August 2006

The pressure losses and rheological properties of butter flowing through stainless‐steel tubing were investigated. Since viscosity is a measure of internal resistance to flow, an extrusion riscometer was constructed to measure apparent viscosity. The apparent viscosity was calculated from the extrusion viscometer data using the Hagen‐Poiseuille equation for flow through tubing. Flow profiles were obtained by alternately forcing butter of different colors through the various lengths of tubing at different temperatures. The velocity gradient was small within the butter except near the wall. A linear relationship was found between the logarithm of apparent viscosity and the logarithm of bulk velocity for a range of 0.001 to 1 ft/sec. The average slope of the regression line was –0.846. As the length of the tubing increased, the average apparent viscosities decreased, though at a decreasing rate. Very small differences were found between the apparent viscosities obtained with 10.5.in. and 14.0.in. lengths of tubing. The influence of temperature on the logarithm of the apparent viscosity was found to be linear, having a slope of ‐0.059 for the range of 55–75°F. A general empirical equation was determined relating the influence of bulk velocity (v, ft/sec) and temperature (T, °F) to the decrease in apparent viscosity (η, lb/ft see):

log η= 4.762 – 0.846 log v– 0.59 T which is considered valid for temperatures between 55 and 75°F.
Anthocyanins in the Lowbush Blueberry, Vaccinium angustifolium
Authors: FRANCIS F. J. , HARBORNE J. B. , BARKER W. G.
Published: August 2006

Fifteen anthocyanin pigments were isolated from the lowbush blueberry, Vaccinium angustifolium Ait., and identified by chromatographic, spectral, and chemical properties. The 3‐monoglucosides and 3‐monogalactosides of delphinidin, malvidin, petunidin, peonidin, and cyanidin were isolated; also present in small quantities were the 3‐monoarabinosides of the same five anthocyanidins. The glucosides were present in much greater quantity than the galactosides or the arabinosides. Several diglycosides were also present, but in quantities too low for identification.
Lemon Oil Analysis. II. Gas‐Liquid Chromatography on a Temperature‐Programmed, Long, Open Tubular Column
Authors: MacLEOD WM. D. , MCFADDEN W. H. , BUIGUES NELIDA M.
Published: August 2006

Lemon oil was analyzed on a highly efficient modified Apiezon L open tubular column with a single injection. Almost all of the more than forty individual peaks were identified by comparison of mass spectra and retention times with those of known compounds. Lemon oils from throughout the world were found very similar in their gas chromatograms; differences were primarily quantitative rather than qualitative.
Immunofluorescent Detection of Staphylococcal Enterotoxin B II. Detection in Foods
Authors: GENIGEQRGIS C. , SADLER W. W.
Published: August 2006

Specific staphylococcal enterotoxin B anti‐serum conjugated with fluorescein isothiocyanate was used successfully for detecting toxin in food smears or food extracts in about 4–5 hr. The fluorescent antibody technique detected minute amounts of enterotoxin—much less than 1 or 0.05 μg/ml, which are the sensitivity limits of single or double gel diffusion tube tests—‐without involving any extraction procedures.
Growth and Sporulation of Smooth and Rough Variants of Bacillus Stearothermophilus in Pea Extract and on Pea Agar
Authors: FIELDS M. L.
Published: August 2006

The influence of rough and smooth variants of Bacillus stearothermophilus on growth and sporulation of each was investigated. The smooth variant grew faster from spore inoculum than the rough variant and produced more acid than the rough when grown separately. However, when grown together, the growth was similar to the smooth; and acid production, as measured by pH, was also the same. When the inoculum was vegetative cells, the growth of rough and smooth were similar to the rough both in growth and pH. More spores were produced by the rough variant than by the smooth variant when grown separately on pea agar or in pea extract. When grown together on pea agar or in pea extract, the total number of spores was less than the rough variant but they were of the rough variant type.
All‐Vegetable Protein Mixtures for Human Feeding. The Development of INCAP Vegetable Mixture 14 Based on Soybean Flour
Authors: BRESSANI RICARDO , ELIAS LUIZ G.
Published: August 2006

Study of the complementary value of soybean and corn proteins in young growing rats resulted in the formulation of INCAP Vegetable Mixture 14: 58% corn flour, 3870 soybean flour, 3% torula yeast, 1% calcium phosphate, and 4,500 I.U. vitamin A per 100 g. The mixture contains approximately 27% protein. Formula 14, evaluated in young growing dogs, was slightly lower in protein quality than casein. Its main limiting amino acid is methionine, but only when fed at a low level of protein. The addition of lysine and threonine in the presence of methionine caused a highly significant increase in protein efficiency ratio. Only a small response was obtained when milk protein replaced Formula 14 protein in isoproteic diets.
Direct Olfactory Demonstration of Fractions of Chicken Aroma
Authors: KLOSE A. A. , PALMER H. H. , LINEWEAVER HANS , CAMPBELL A. A.
Published: August 2006

A general method of dividing and subjectively evaluating the fractions of cooked chicken aroma was developed. The fractions were separated by passing nitrogen gas laden with the freshly formed aroma through solid absorbents or solutions of metal salts. The unabsorbed effluents were then characterized or identified in terms of the dominant odor by a trained panel. Absorbents were selected for their ability to permit passage of easily identified aroma fractions and for their general inability to form, react with, or concentrate on a volume basis the unabsorbed fractions of interest. The role of hydrogen sulfide was established in two ways: 1) when essentially all aroma constituents except hydrogen sulfide were removed from the nitrogen stream by anhydrous calcium sulfate (or calcium chloride or calcium carbonate), the residual aroma was easily recognized as hydrogen sulfide; and 2) when hydrogen sulfide was removed by any of a variety of heavy metal salts, a completely foreign disagreeable aroma remained that indicated the blending or masking effect of the hydrogen sulfide. When hydrogen sulfide and other components were removed by magnesium oxide, an ammoniacal odor characteristic of ammonia or aliphatic amines was exposed. Many absorbents or combinations of absorbents were found that trapped all fractions of the cooked chicken aroma.
Lipid Oxidation in Frozen Vegetables in Relation to Flavor Change
Authors: RHEE KI SOON , WATTS BETTY M.
Published: August 2006

The TBA test, adapted for vegetable material, was useful in following lipid oxidation in frozen peas. Gas‐liquid chromatographic analysis for the loss of unsaturated fatty acids was not feasible for determining lipid oxidation in un‐blanched vegetables. This work has established that rancidity is not a main cause of flavor deterioration in frozen Blackeye peas (Vigna sinensis) and possibly in other frozen vegetables. The amount of lipid oxidation occurring in frozen raw peas was too small to produce rancid odors. Lipoxidase was rapidly inactivated by a short blanching time, and no regeneration of the enzyme occurred during frozen storage of garden peas (Pisum sativum).
Changes in the Content of Free Amino Acids During Roasting of Cocoa Beans
Authors: PINTO A. , CHICHESTER C. O.
Published: August 2006

The major changes noted in the roasting of cocoa beans are the destruction of amino acids and reducing sugars, followed by the production of volatile earbonyl compounds. The relation between these reactions was demonstrated by means of amino acid analysis, titrimetric determination of the reducing sugars, and gas chromatography. It is postulated that the majority of the earbonyl compounds produced during the course of the roasting process are the result of the oxidative deamination of free amino acids.
Some Catechins and Proanthocyanidins in the Cores of Bartlett Pears
Authors: NORTJE B. K.
Published: August 2006

Two catechins and two proanthocyanidins were isolated from the cores of Bartlett pears. The cateehins, (+)‐catechin, and (‐)‐epicateehin were obtained in crystalline form. Proanthocyanidin P‐l was found to he identical with the major proanthocyanidin of cacao beans. Proanthocyanidin P‐2 was found to consist of at least three flavan units. Treatment of proanthoeyanidin P‐2 with sulfurous acid yielded proanthocyanidin P‐l.
Studies on Free Amino Acids in Sponges, Doughs, and Baked Soda Crackers and Bread
Authors: MORIMOTO TERUHIKO
Published: August 2006

Free amino acids decreased markedly during an 1%hr cracker sponge fermentation or during a 6‐hr straight dough bread fermentation. No commercial proteases were used. However, the free amino acids increased after 48 and 72 hr of cracker sponge fermentation, respectively. This suggested that the amino acids were metabolized by microorganisms during active growth at a faster rate than they were being formed from the protein by native proteases. Later, the amino acids accumulated as the rate of active fermentation and growth subsided, Pro. teolytic activities did not change with fermentation time, suggesting that microorganisms did not release additional proteases. The amino acid content of soda crackers made with a long sponge fermentation decreased during baking. Likewise, the free amino acid content of bread crust decreased during baking, while the free amino acid content of the crumb remained essentially constant.

When a commercial protease was added to a soda cracker sponge and the sponge fermented for 18 hr, the free amino acids in the baked products increased to a level equivalent to that of the soda crackers made with a 72‐hr sponge fermentation without the use of commercial protease.
Protein Changes Related to Ham Processing Temperatures I. Effect of Time‐Temperature on Amount and Composition of Soluble Proteins
Authors: COHEN EDWARD H.
Published: August 2006

Knowledge of protein changes produced by heat is basic to the development of a needed analytical method for determining whether canned meats have been pasteurized at high enough temperatures. Ground cured uncooked ham was heated, with different programming, to temperatures up to 165°F; and the influence of the treatments on the amount and composition of proteins soluble in 0.9% NaCl solution was determined. Rate of heating as well as the temperature reduced the amount of ex‐tractable protein. Fractionation of soluble proteins by disc electrophoresis showed five components to be relatively resistant to heat coagulation. One of these components was identified as an acid phosphatase.
Enrichment of Volatile Samples by Syringe Collection
Authors: HOFFMANN R. L. , LIST G. R. , EVANS C. D.
Published: August 2006

Volatile samples for gas chromatographic analysis can he collected and enriched by slow passage through a gas‐syringe barrel packed with solvent‐dampened cotton. Then the condensate can be injected into a gas chromatograph directly from the same syringe.
Effect of Soaking and Germinating on the Nutritive Value of Navy Beans
Authors: KAKADE M. L. , EVANS ROBERT JOHN
Published: August 2006

The effect of soaking or germination on the protein content, trypsin inhibitor activity, and hemagglutinin activity of navy beans was studied. Soaking navy beans for 1–4 days decreased the trypsin inhibitor activity, and especially the hemagglutinin activity. The decrease in protein content due to soaking did not account for all of the decrease in anti‐trypsin and hemagglutinin activity. No significant changes were observed in hemagglutinin activity due to germination, although some decrease in the trypsin inhibitor activities of germinated beans was noticed. Protein content increased progressively in beans germinated l‐4 days, and decreased in beans soaked 1–4 days. Rats fed raw, soaked, and germinated navy beans as a source of dietary protein lost weight and died 8–16 days after the beginning of the experiment. It is concluded that soaking prior to heating is not necessary to eliminate the toxicity of navy beans.
Effect of Sulfite and Ascorbic Acid on Mushroom Phenol Oxidase
Authors: MARKAKIS P. , EMBS R. J.
Published: August 2006

In model systems containing mushroom phenol oxidase and o‐diphenolic or monophenolic substrates in phosphate buffer, pH 6.5, sulfite initially did not protect the ascorbic acid from oxidation by the quinones formed enzymatically. The sulfite, however, gradually decreased both the diphenolase and monophenolase activity of the enzyme and thereby diminished the overall destruction of ascorbic acid. Under certain conditions, ascorbic acid counteracted the sulfite inhibition of the monophenolase activity of the enzyme.
Interaction of Low‐Density Lipoprotein (LDL) from Yolk Plasma with Methyl Orange
Authors: NOWAK C. M. , POWRIE W. D. , FENNEMA O.
Published: August 2006

The surface characteristics of plasma low‐density lipoprotein (LDL) in various buffers were investigated by determining the binding of an anionic dye, methyl orange, during equilibrium dialysis at 10°. As the buffer pH increased from 4.5 to 8.6, the binding capacity of native LDL diminished. Additional experiments were carried out at pH 6.5, the normal value for egg yolk and plasma. A plot of dye concentration vs. dye binding by native LDL produced a curve with a shape similar to that for ‐β lipoprotein from blood. Native LDL, with only about 15% protein, bound as much dye as a pure protein, β‐lactoglobulin. The LDL from pasteurized yolk (63 and 64.8°C) bound as much dye as LDL from native yolk. Sodium chloride and sucrose did not restrict the dye adsorption to native LDL. When yolk plasma was treated with bromelain, the dye‐binding capacity of isolated LDL was somewhat reduced.
Kinetic Behavior and Mechanism of Inhibition in the Maillard Reaction. II. Mechanistic Considerations in the Reaction Between D‐Glucose and Glycine
Authors: SONG PILL‐SOON , CHICHESTER C. O.
Published: August 2006

The mechanism of the initial Maillard reaction was investigated in kinetic, autoradiographic, spectroscopic, and model studies. Results indicate that the initial reaction involves the formation of glucosylglycine from aldehydic glucose and the free amino group of glycine, followed by base‐catalyzed conversion of glucosylglycine into a, βunsaturated aldimine, with the steady‐state concentration of the latter accumulated during the induction period and undergoing subsequent reactions to yield melanoidins. Evidence to support this mechanism is presented and discussed. Also proposed is a possible mechanism for the melanoidin formation in the reaction. Side reactions giving rise to products of “browning reaction”, such as from hydroxymethyl furfural, were not considered.
The Anthocyanin Pigments of Black Raspberries
Authors: DARAVINGAS GEORGE , CAIN R. F.
Published: August 2006

The chemical structure of the major red pigments of the black raspberries, Monger variety, was elucidated. These components were cyanidin‐3‐glucoside, cyanidin‐3,5‐diglu‐coside, cyanidin‐3‐diglucoside, and cyanidin‐3‐rhamnoglucoside‐5‐glucoside. The pigments were isolated, purified, concentrated, and then separated into individual anthocyanins by column and paper chromatography. The separated anthocyanins were identified by paper chromatographic and spectrophotometric analysis of the individual pigments and their products after specific chemical degradations.
An Apparatus for the Isolation of Volatile Compounds from Foods
Authors: HERZ KARL O. , CHANG STEPHEN S.
Published: August 2006

Volatile compounds that may contribute flavor to a wide variety of foods can be isolated in an apparatus which is described. It utilizes the principle of flash evaporation and vaporization from a continuous thin heated film. Liquid foods, such as fruit juices or beer, need no preparation, but foods such as meat and potato chips are first made into a fine water slurry. Vaporized food constituents and water are recovered by condensation in a series of specially designed cold traps. Features and performance of the apparatus are discussed.
Proanthocyanidins in the Apple
Authors: VAN BUREN J. P. , SENN G. , NEUKOM H.
Published: August 2006

A study was conducted on the acetone‐ and ethyl‐acetate‐extractable flavan polyphenols of Waldhöfler apples, an astringent‐tasting juice variety. The extracts were examined by cellulose thin‐layer chromatography with 5% n‐butanol and n‐butanol—acetic acid—water (BAW) as the developing solvents. (—) Epicatechin was the major monomeric flavan found; (+) catechin was present in smaller amounts. A large number of unknown flavans were also detected; most of these are thought to be dimerie or oligomeric in composition, since their RI values did not correspond to those of any known flavans. The predominating unknown substance, R1 0.58 in 5% n‐butanol and 0.46 in BAW, was purified from ethyl acetate extracts by polyamide chromatography followed by solvent fractionation. The pure compound had a marked astringent taste. The IR and UV spectra were typical of flavans. On hydrolysis, cyanidin and epicatechin were produced. Methylation with diazomethane yielded a compound with the empirical formula C3sH42O12H2O with a methoxyl content of 33.7%. NMR spectra indicated that condensations involved the A ring. Hydrolysis of the methylated derivative yielded tetramethyl epicatechin and a substance corresponding to tetramethyl flavan‐3,4‐diol and other unidentified intermediate products. It is thought that the purified proanthocyanidin is a dimer, or possibly an oligomer, containing (‐) epicatechin and 5,7,3′,4′‐flavan‐3,4‐diol as constituents.

The other unknown flavans, not isolated in pure form, yielded cyanidin, (—) epicatechin, and a small amount of pelargonidin on hydrolysis.
Composition of Raw and Roasted Lamb and Mutton II. Amino Acids
Authors: BLUM AMOS E. , LICHTENSTEIN HAROLD , MURPHY ELIZABETH W.
Published: August 2006

Microbiological assay values are reported for content of 18 amino acids in separable lean of raw and roasted rib‐loin and leg cuts of lamb and mutton. These values agreed well with values obtained in other laboratories. The amino acid content of lamb protein tended to be constant and was not affected by cut or by roasting. Retentions of amino acids in lamb lean after roasting were essentially complete.
A Classification of Objective Methods for Measuring Texture and Consistency of Foods
Authors: BOURNE M. C.
Published: August 2006

The numerous methods for objectively measuring the textural properties of foods are classified on the basis of the variable or variables that are the basis of measurement. Physical methods of measurement are classified under the headings force‐measuring, distance‐measuring, time‐measuring, energy‐measuring, ratio‐measuring, multiple‐measuring, and multiple‐variable instruments. There are also some chemical methods for measuring texture objectively. Methods that do not fit into any of the above categories make a special, miscellaneous group. Examples are given of the kinds of instruments found in each category.
Post‐Mortem Changes in Muscle II. Chemical and Physical Changes in Pork
Authors: BODWELL C. E. , PEARSON A. M. , WISMER‐PEDERSEN J. , BRATZLER L. J.
Published: August 2006

The chemical changes occurring from 0 to 24 and/or 48 hr post‐mortem were followed in longissimus dorsi muscle from 18 pork carcasses. In an attempt to induce soft, watery pork, one side from each of 13 carcasses was placed at 37°C immediately after slaughter, and the other side of each carcass was subjected to ‐29°C. Values for pH, glycogen, total reducing sugars, and lactic acid differed markedly at 0 time. Carcasses from Poland China pigs showed a stoichiometric relationship between the post‐mortem decrease in glycogen and the corresponding accumulation of lactic acid and total reducing sugars. This relationship was less apparent in Hampshire pigs. The 37°C treatment did not consistently result in soft, watery and pale muscle, as was expected from other reports. This suggests that exposure of muscle to a low pH at a high temperature per se does not necessarily cause the soft, watery, and pale appearance. A loss in fibrillar water‐binding capacity as a result of low pH values and high muscle temperatures confirmed earlier investigations. However, the decrease in fibrillar water‐binding capacity as a result of the low pH at high muscle temperatures did not usually make the muscle appear soft and watery. Results indicate that even though a loss in fibrillar water‐binding capacity occurs as a consequence of a low pH and high temperature, and is a characteristic frequently encountered in soft, watery muscle, low fibrillar water‐binding capacity by itself is not the primary causal factor in making pork muscle appear soft and watery. Post‐mortem levels of ATP, creatine phosphate, lactic acid, total reducing sugars and glycogen are reported and compared with literature values.
Development of a Radiation Process for Some Indian Fruits: Mangoes and Sapodillas
Authors: DHARKAR S. D. , SAVAGAON K. A. , KUMTA U. S. , SREENIVASAN A.
Published: August 2006

A combination heat‐radiation process has been evolved for sterilizing mango and sapodilla slices in cans. The fruit, after peeling and slicing, is packed in sanitary cans with sucrose syrup, and the respiratory enzymes are inactivated by heating for 10 min at 70°C. The cans are next evacuated for 6 min at a vacuum of 28 inches Hg, vacuum doubled‐seamed, and irradiated with a total dose of 4 × 105 rads at room temperature.

Organoleptic evaluation, vitamin retention, and sterility tests show that these processing conditions are optimum and give an acceptable product. Canned mangoes showed progressively lower acceptability with radiation doses above 4 × 105 rads, compared with the thermally processed product. Sapodillas, on the other hand, did not show appreeiable deterioration up to 1.2 × 106 rads.
Effect of Storage Temperature on the Cytochrome Oxidase and Polyphenol Oxidase Activities and Phenolic Content of Potatoes
Authors: MQNDY N. I. , GEDDEDAHL S. BOND , MOBLEY E. OWENS
Published: August 2006

Ontario and Pontiac potatoes, respectively representing varieties susceptible and resistant to precooking blackening, were examined for phenolic content and for cytochrome oxidase and polyphenol oxidase activities following storage at 4‐O and 50°F. The study was conducted for two consecutive years. In each of the two years the phenolic content of both varieties was significantly higher in potatoes stored at 40°F than in potatoes stored at 50°F. Both varieties had higher cytochrome oxidase and polyphenol oxidase activities when stored at 50°F than when stored at 40°F. The lower enzyme activities at 40°F may be responsible, in part, for the accumulation at that temperature of phenolic substances which serve as substrates for the enzymes. The higher phenolic content at lower temperatures may account for the greater discoloration of the potatoes.
The Fatty Acid Composition of Commercially Hydrogenated Fish Oils
Authors: LAMBERTSEN G. , MYKLESTAD H. , BRAEKKAN O. R.
Published: August 2006

Five samples of industrially hydrogenated fats of marine origin were analyzed for fatty acid composition by the combined methods of group‐separation by thin‐layer partition chromatography followed by gas‐liquid chromatography of each group.

The general fatty acid composition was 30–45% saturated acids, 45–55% monoenoic acids, and lo‐20% polyenoic acids. A substantial part of the polyenoic acids were trienoic acids, the rest dienoic. The presence of tetraenoic acids could be ascertained in the low‐melting samples (mp 30–32°C).
Microbiology and Chemistry of Fermented Fish
Authors: SAISITHI PRASERT , KASEMSARN RUNG‐ORN , LISTON J. , DOLLAR ALEXANDER M.
Published: August 2006

The microbiology and chemistry of Thai fish sauce was investigated in relation to the development of flavor and aroma. Total viable count decreased steadily as fermentation time advanced. The counts were higher when media containing 10% NaCl were used than when media containing 0.5% NaCl were used. Approximately 70% of the bacterial isolates from a nine‐month‐old fish sauce were halophiles of Bacillus types. These bacteria produced volatile acids from cultures in a medium prepared by hydrolyzing rockfish (Sebastodes sp.) with a mineral acid. A diethyl‐ether‐ethanol‐soluble fraction contained the typical aroma of fish sauce. This extract could be separated further by column chroma tography (AGl‐X8, formate form) into a fraction containing amino compounds and a second fraction containing weakly acidic compounds. The amino acids, principally glutamic acid, histidine, proline, etc., and other amines were identified by thin‐layer chromatography. The identification of acidic compounds has not been completed.
Competitive Growth of Microorganisms and Fluorescence Development on inoculated Chicken
Authors: KRAFT ALLEN A. , AYRES JOHN C.
Published: August 2006

Studies were conducted to determine the effects of competitive growth of microorganisms and development of fluorescence on inoculated poultry during refrigerated storage. Pseudomonas fluorescens rapidly outgrew Staphylococcus aureus in broth at 15°C when the initial concentration of staphylococci was about ten times as great as that of the Pseudo‐monas. On stored chicken previously chilled in water containing various levels of pseudo‐monads, S. aureus, Echerichia coli, and Streptococcus faecalis, growth of the fluorescing pseudomonads greatly surpassed that of the other organisms. Fluorescing bacteria attained large populations on chicken even when S. aureus initially outnumbered the fluorescing spoilage organisms by 100:1. Little change occurred in the populations of S. aureus recovered from inoculated poultry during storage for one week at 5°C.
Sensory Analysis of Odor Qualities in Terms of the Stereochemical Theory
Authors: AMOORE JOHN E. , VENSTROM DELPHA
Published: August 2006

In correlating chemical constitution with odor character, the matching‐standards method of Schutz was modified for use with the seven primary odors of the stereochemical theory. Information is given regarding suitable standard chemicals, threshold concentrations, and matching odor intensities. This method of odor analysis provides, for any unknown odor, a set of seven numerical values representing the similiarities between that odor and each of the seven standards. Odor analyses are reported for the seven standards themselves, for mixtures of two or three standards, and for 21 compounds closely related in odor to one or another of the standards. The analyses by the panel agreed well with literature descriptions of the odors. The method was further applied to analyzing a series of 18 compounds with complex odors involving two or more primes, compounds with odors disputed in the literature, and compounds with no description at all. Examples are mentioned of the similar odors of isosteric compounds, and the divergent odors of isomers. The experimental findings are generally in keeping with the stereochemical theory.
Effect of Viscosity on the Detection of Relative Sweetness Intensity of Sucrose Solutions
Authors: STONE HERBERT , OLIVER SHIRLEY
Published: August 2006

Data are presented to demonstrate the relationship between the subjective mouthfeel of selected gums, cornstarch, gum tragacanth, carboxymethyl cellulose and methyl cellulose, and their rheological properties as measured by a viscosimeter. The mouthfeel of the gum solutions was evaluated subjectively on a 7‐point intensity scale of degree of sliminess. The viscous solutions containing sucrose were ranked more sweet by most of the panel; however, rankings between pairs of viscous and non‐viscous solutions were not significantly different. Sucrose detection thresholds for the panel also changed as a function of viscosity. Sensitivity for sucrose was highest in water, lowest in the presence of carboxymethyl cellulose, and intermediate with cornstarch. The results of these tests and their application to foods is discussed.
Flavonol Glycosides in Cranberries
Authors: PUSKI G. , FRANCIS F. J.
Published: August 2006

SUMMARY
The yellow flavonol glycosides were isolated from cranberries (Vaccinium macrocarpon, Ait.) and identified by chromatographic, chemical, and spectral studies. The major pigment was quercetin‐3‐galactoside, followed by quercetin‐3‐hamnoside, quercetin‐3‐arabinoside, quercetin, myri‐cetin‐3.arabinoside, and myricetin‐3‐digalactoside.
Changes in Lipid Composition of Sweet Potatoes as Affected by Controlled Storage
Authors: BOGGESS T. S. , MARION J. E. , WOODROOF J. G. , DEMPSEY A. H.
Published: August 2006

SUMMARY— The fatty acid composition of the lipids extracted from Georgia Red and Centennial varieties of sweet potatoes was studied to determine changes during storage at 15.5, 10, and 4.5°C. The two varieties did not differ initially in the relative proportions of fatty acids. However, changes in fatty acid composition were noted during storage and appeared to be mere pronounced at low storage temperatures. The most consistent changes noted were an increase in tetra‐cosaenoic acid and a decrease in short chain saturated acids. The Centennial variety contained higher levels of total lipids, which were generally reflected in higher levels of the three fractions, (1) non‐phospholipids, (2) cephalin and (3) lecithin. The increase in total lipids and the individual lipid fractions with storage is indicative of two processes that may have occurred in the stored roots. The lipids may have become more extractable as the respiring potato underwent compositional changes, or lipids were being synthesized from non‐lipid components. Although changes observed in the relative proportions of fatty acids during storage at different temperatures were not always consistent, the possibility is suggested that changes in fatty acid composition may be related to changes in quality of the potato during storage.
Muscle Properties of Physically Restrained Stressor‐Susceptible and Stressor‐Resistant Porcine Animals
Authors: JUDGE M. D. , CASSENS R. G. , BRISKEY E. J.
Published: August 2006

SUMMARY— Studies of the effects of duration of physical restraint of porcine animals revealed breed influences on the responses occurring in muscles. The rate and extent of glycolysis and the color and gross morphology of the muscles of Poland China animals became more severely affected as the duration of restraint increased. The muscles of Chester White animals, however, responded to the stressor initially but, with prolonged restraint, returned to glycolytic and morphological states resembling those of unrestrained animals. The results emphasize the importance of genetic influences on stress responses and resultant muscle morphology and indicate that a specific treatment may ultimately produce opposite effects in animals that differ in susceptibility to stressors.
Determination of Calcium and Magnesium in Meat
Authors: INKLAAR P. , SANDIFORT J.
Published: August 2006

SUMMARY— A method is given for determining calcium and magnesium in meat. The influence of several parameters such as pH, time, orthophosphate addition, quantity of ZrOCl2 and meat, has been described. Information is presented on the use of zirconylozychloride to eliminate interfering substances. The amount of calcium found is generally higher than figures given in the literature. If no orthophosphates are present in the sample, they should be added.
A Statistical Method for the Analysis of Peppermint Oils and Other Complex Mixtures
Authors: HAWKES S. J. , WHEATON M. D.
Published: August 2006

SUMMARY— A statistical method, preferably operated by a a computer, is proposed for the analysis of data on complex mixtures where the information sought involves a number of small changes in chemical composition, each of which is individually within the normal range of variation of the mixtures. When the method is applied to the identification of geographical origins of peppermint oils and mixtures of peppermint oils, the results are a substantial improvement on those from previous methods, though still leaving some uncertainty. It is expected that more complete chemical analysis will greatly improve the confidence level.