bluuebunny/crossref_metadata_2025 huggingface dataset:
Sesquiterpenes. I. Nootkatone, A New Grapefruit Flavor Constituent
Authors: MacLEOD WILLIAM D. , BUIGUES NELIDA M.
Published: August 2006

The bicyclic conjugated sesquiterpene ketone, nootkatone, has been found in grapefruit peel oil and in peel‐oil‐free grapefruit juice. The flavor intensity of grapefruit oil appears to be related to the relative abundance of nootkatone. A combination of gas‐liquid chromatography and thin‐layer chromatography revealed the presence of this ketone, which was identified by its infrared spectrum and the melting point of its 2,4‐dinitrophenylhydrazone derivative. Traces of nootkatone were found also in bergamot, lemon, lime, orange, and tangerine oils.
Cheddar Cheese Flavor: Gas Chromatographic and Mass Spectral Analyses of the Neutral Components of the Aroma Fractiona
Authors: DAY E. A. , LIBBEY L. M.
Published: August 2006

The aroma fraction from the fat of high‐quality raw‐milk Cheddar cheese was isolated by centrifugation of the intact cheese and passing the recovered fat through a molecular still at 40°C. The aroma fraction was separated by gas chromatography on packed columns containing polar and nonpolar phases and by programmed‐temperature capillary‐column gas chromatography. The effluent from the latter column was admitted directly to the inlet of a rapid‐scan mass spectrometer enabling concurrent recordings of mass spectra for each chromatographic peak. The aroma fraction was separated into approximately 130 components by the capillary column. By correlation of gas chromatography and mass spectral data, most of the major neutral components were characterized. These included aldehydes, methyl ketones, primary and secondary alcohols, esters of the primary and secondary alcohols and fatty acids, γ‐lactones, and the isomeric lactides of lactic acid.
Post‐Mortem Changes in Physical and Chemical Properties of Bovine Musclea
Authors: GOLL DARREL E. , HENDERSON D. W. , KLINE E. A.
Published: August 2006

Post‐mortem changes in tenderness and protein solubility were studied in bovine semitendinosus muscles. Muscles excised immediately post‐mortem were compared with muscles left attached to the skeleton. Post‐mortem times of 0, 6, 12, 24, 72, and 312 hr were studied. Sarcoplasmic protein solubility was highest immediately after slaughter and lowest in muscles left attached to the skeleton. Myofibrillar protein solubility was decreased in muscles left attached. Protein solubility changed during the first 6 hr post‐mortem but not during the 6‐ to 312‐hr aging period. Muscles left attached to the skeleton were least tender immediately after death and gradually increased in tenderness during post‐mortem aging. Excised muscles were least tender 6–12 hr post‐mortem and became progressively more tender thereafter. Even after 312 hr of aging, excised muscles were less tender than muscles still attached to the skeleton. Protein solubility did not appear to be related to tenderness. Possible relationships of muscle contraction to tenderness were discussed.
Age‐Associated Changes in Bovine Muscle Connective Tissue. I. Rate of Hydrolysis by Collagenasea
Authors: GOLL DARREL E. , HOEKSTRA W. G. , BRAY R. W.
Published: August 2006

Age‐associated structural changes in collagenous residues isolated from the loose connective‐tissue network found within bovine biceps femoris muscle were studied with collagenase used as a structural probe. Rate of enzymatic digestion was measured by following the release of soluble protein, hydroxyproline, and ninhydrin‐positive material into the medium surrounding the fibrous residues. Under the conditions of the experiment, 8–11% of the protein and 8–21% of the hydroxyproline in the residues were solubilized after 12 hr of incubation with collagenase. Samples from four age groups were studied: Group I, veal, 40–49 days old; Group II, steers, 403–495 days old; Group III, cows, 4 years, 8 months to 5 years, 5 months old; Group IV, aged cows, 10 years, 2 months and 10 years, 5 months old. The groups ranked I, III, IV, and II, from fastest to slowest, in rate of hydrolysis by collagenase. However, it was postulated that the larger amounts of lipid associated with the Group II samples acted to shield collagenase‐labile bonds and cause a slow rate of hydrolysis. Making this assumption, it appears that susceptibility to collagenase digestion of loose connective tissue follows an age pattern similar to that reported for skin and tendon collagen.
Age‐Associated Changes in Bovine Muscle Connective Tissue. III. Rate of Solubilization at 100°Ca
Authors: GOLL DARREL E. , BRAY R. W. , HOEKSTRA W. G.
Published: August 2006

The rate of solubilization of insoluble connective‐tissue residues obtained from the loose connective‐tissue network within bovine biceps femoris muscle was studied in phosphate‐buffered (pH 7.0) aqueous medium at 100°C. Eleven animals from four age groups were used: Group I, three veal calves, 40–49 days old; Group II, three steers, 403–495 days old; Group III, three cows, 4 years, 8 months to 5 years, 5 months old; Group IV, two cows, 10 years, 2 months and 10 years, 5 months old. The conditions under which the samples were heated resulted in the solubilization of 95–100% of the hydroxyproline and 72–94% of the protein in the samples within 240 min. The release of soluble protein and soluble hydroxyproline indicated that collagen from the younger animals was solubilized (i.e. converted to gelatin) much more rapidly than collagen from the older animals. The low hydroxyproline content of the soluble protein released from the Group I samples was discussed, and it was suggested that these samples contained some reticulin. The average molecular weight of the soluble protein decreased with increasing age. The findings were discussed with relation to the results reported in two previous papers and the extent and strength of cross‐linkages in collagen from animals of different ages. It was suggested that the number and strength of cross‐linkages in collagen may play an important role in meat tenderness.
The Effect of Selected Carbohydrates and Plant Extracts on the Heat Activation of Bacillus Stearothermophilus Spores
Authors: FIELDS M. L. , FINLEY N.
Published: August 2006

Spores of two suspensions of Bacillus stearothermophilus strain M were heat‐shocked in monosaccharides, disaccharides, and polysaccharides. The concentration had significant effects. The dominant significant trend was for reduced counts with increased concentrations of carbohydrate. These significant effects are thought to he associated with osmotic pressure. It would appear, therefore, that there was considerable difference in the osmosensitivity of spores in these populations. Spores were activated as well as suppressed when heated in plant extracts. Pea, spinach, and corn extracts tended to suppress spore germination, and green bean extract stimulated spore germination.
A Dietary Evaluation of Synthetic Amino Acid Amides
Authors: CROSBY DONALD G. , THOMSON J. R. , JOHNSON HERBERT E.
Published: August 2006

Growth of mice on a complete synthetic diet has been used to determine the ability of synthetic amino acid derivatives to replace the corresponding essential metabolites in nutrition. In a series of range‐finding experiments, it was found that dietary valine, phenylalanine, leucine, methionine, and, to a lesser extent, isoleucine could be effectively replaced by the corresponding DL‐amides or amide salts. In addition, DL‐valinamide salts could be administered in aqueous solution to supplement a solid valine‐free diet. The physical, chemical, and biological properties of amino acid amide salts may make them of special value in protein supplementation.
Measurement of Hypoxanthine in Fish as a Method of Assessing Freshness
Authors: SPINELLI J. , EKLUND M. , MIYAUCHI D.
Published: August 2006

The hypoxanthine contents of fresh fillets taken from three species of fish in Pacific Northwest waters were found to he almost zero, and increased at a fairly uniform rate during the first 8‐10 days of storage in melting ice. The hypoxanthine content reached maximum values in about 8‐10 days. Total nucleotides reached a minimum in about 6‐8 days. Fillets stored at −20°F showed practically no change in hypoxanthine content during four, months of storage.

Hypoxanthine can be rapidly measured and the data can be used to judge the length of time fish has been held in storage.
Iron Sulfide Blackening in Canned Protein Foods. Interactions of Constituents in the Vapor Phasea
Authors: PIGOTT GEORGE M. , GUARDIA ENRIQUE J. , DOLLAR ALEXANDER M.
Published: August 2006

The formation of volatile bases and volatile acids during heat processing of albacore tuna loin sections was studied, using a closed system swept with nitrogen gas. The cell containing the tuna was heated gradually to 100°C, and the volatile acids and bases were trapped in standardized solutions. During the first 80 min of heating, at precooking temperatures, volatile acid evolved exceeded by threefold the slight amounts of volatile base (less than 0.5 mcq per 1000 g). Later during the heating cycle equal amounts of volatile acids and bases were formed.

The ratio of sulfur to iron responded directly to the initial vacuum present in canned tuna. At high vacuum the ratio was 0.575. Sulfur was absent from the black deposits when the cans were sealed without evacuation, even when high levels of cystine were added. In commercially packed shrimp the sulfur to iron ratio was 0.322, which is consistent with a deposit of mixed oxides of iron, combined with ferrous sulfide. Addition of acetic acid (a volatile acid) at 10 mM per can suppressed the formation of black deposits at all closing vacuums in a model system containing added cysteine, while the addition of ammonium hydroxide (volatile base) or no addition resulted in the formation of black deposits at 26 inches Hg of closing vacuum.
Influence of Freezing Egg Yolk Plasma on the Properties of Low‐Density Lipoproteins
Authors: SAARI A. , POWRIE W. D. , FENNEMA O.
Published: August 2006

When yolk plasma was frozen for 24 hr between −20 and −25°C, the thawed mass had a pasty consistency. After freezing and thawing plasma, only 15% of the total lipoproteins were soluble in 10% NaCl. The two lipoproteins fractions, FLPL1, and FLPL2, isolated from the salt‐soluble material had chemical and physical properties similar to those for native plasma lipoproteins LPL1, and LPL3. With papin treatment, heated FLPL2, was degraded to the extent that all of the nitrogenous constituents were soluble in TCA solution. The influence of freezing LPL2 solutions at various pH values on the physical properties of the thawed solutions was examined.
Color Measurement of Translucent Food Samplesa
Authors: LITTLE ANGELA C.
Published: August 2006

Reflectance measurements of foods and food products can serve as rapid nondestructive indicators of quality. The problem of sample presentation to photoelectric reflectance units is easily solved with opaque, non‐light‐transmitting samples. With translucent materials, problems arise relating to internal light transmission and consequent light loss through trapping. A method of overcoming these problems is suggested, involving the application of Kubelka‐Munk colorant layer analyses. Appleberry‐applesauce mixtures with color differences controlled by addition of red food coloring, and artificial systems consisting of agar, cellulose, and controlled increments of yellow food dye, were evaluated subjectively and objectively. Direct measurement of deep layers of samples by photoelectric tristimulus colorimetry was not as successful in ranking the samples as was the visual panel. The measurement of thin layers of sample backed by white standard plaques increased the separation of successive samples in color space to conform closely to visual experience.
Sugars in Red Tart Cherries and Their Changes During Maturationa
Authors: CONSTANTINIDES SPIROS M. , BEDFORD C. L.
Published: August 2006

Sugars in red tart cherries (Prunus cerasus L. var. Montmorency) comprise 50‐60% of the total dry matter of the edible portion of the fruit. Paper, thin‐layer, and column chromatography were used to investigate the sugars present and changes in the main sugars during maturation. Seven sugars were found. Glucose and fructose comprised 99%, or more of the total sugars. Five reducing oligosaccharides in minute quantities were found by column and paper chromatography. These were not identified. Paper chromatography and the Dubois calorimetric procedure were used to quantitatively determine glucose and fructose. The ratio of glucose to fructose during ripening was constant, about 1.1‐1.0. On a dry‐weight basis, the sugars reached their highest level when the cherries became fully red, then dropped slightly and remained relatively constant during the rest of the harvest period. Recovery of glucose and fructose by this procedure was 100±3.7%.
A Comparison of Two Methods for the Determination of Lactic Acid in Muscle
Authors: SCHWEIGER A. , GÜNTHER H.
Published: August 2006

Two methods of determining lactic acid in mammalian tissues are compared. Lactic acid was estimated by the procedure of Barker and Summerson and by the enzymatic test with lactic dehydrogenase. The standard error of the mean at the 5% level was 5.8% for the former and 3.1% for the latter. Values for lactic acid found by both methods did not agree in most cases. Differences of over 40% were detected. After chromatographic purification of the extracted lactic acid, the Barker and Summerson values were identical with the enzymatic values. Lactic acid isolated by thin‐layer chromatography was identified by its infrared spectrum as the p‐phenyl‐phenacylester. The enzymatic test should be regarded as the more reliable procedure for determining lactic acid in meat.
Studies on Honey Inhibine. 4. Destruction of the Peroxide Accumulation System by Light
Authors: WHITE JONATHAN W. , SUBERS MARY H.
Published: August 2006

Conflicting reports on the sensitivity of honey inhibine (accumulated hydrogen peroxide) to light are resolved by demonstration of great variability in the effect of light on the peroxide accumulation value of different honeys. Destruction of the glucose oxidase in honey by photo‐oxidation has been observed. This enzyme, responsible for peroxide production in diluted honey, is destroyed in either full‐density or diluted honey by visible radiation, with the 425‐525 mμ region most effective. General laboratory illumination, particularly fluorescent‐tube lighting, is highly destructive to inhibine in a sensitive full‐density honey. The liability of the inhibine of a honey sample to photo‐destruction depends on the presence of a heat‐ and light‐stable, non‐volatile sensitizing material; photo‐oxidation is greatest at pH 3 and negligible at pH 6‐7. Immediate adjustment of the pH of honey samples prepared for bacteriological inhibine assay is therefore essential. Inhibine content of honey is not recommended as a quality factor, because of wide variation in light and heat susceptibility and in distribution according to floral source.
Role of Incidental Microflora in Natural Decomposition of Mucilage Layer in Kona Coffee Cherriesa
Authors: FRANK HILMER A. , CRUZ AMY S. DELA
Published: August 2006

The mucilage layer of ripe Kona coffee cherries decomposes naturally during processing. Mucilage breakdown does not occur if the cherry surface is disinfected chemically or if the outer skin remains unbroken. Decomposition depends upon the presence of pectinolytic bacteria, not, as sometimes reported, upon enzymatic activity of the coffee cherry.
Relation of “Breast Swab” to “Drip” Bacterial Counts in Tray‐Packed Chicken Fryers
Authors: MERCURI A. J. , KOTULA A. W.
Published: August 2006

Four different methods were used to sample drip from fresh tray‐packed cut‐up fryer chickens during storage at 34°F. In the first method, one ml of drip was obtained from packages used for breast swab‐count determinations. The second method consisted of sampling drip from packages in which drip was allowed to accumulate throughout storage. In the third method, the sample of drip was taken from packages from which all drip that had accumulated between sampling days was removed. In the 4th method, drip from packages that been stored for one day was placed in test tubes and kept in the storage room with the packages. This drip was then sampled for bacterial counts at various intervals during storage.

With each of the 4 methods, the numbers of bacteria per ml increased during storage at a rate paralleling that of the breast swab count. Significant positive correlations were found between the log of the breast swab count and the log of the drip count for all 4 methods.

A significant positive correlation was also found between the log of the breast swab count and the log of the drip count when packages of frozen thawed tray‐packed cut‐up fryers stored at 34°F were tested. The rates of increase in numbers of bacteria, both on the breast skin surface and in the drip were lower for the frozen thawed samples than for the fresh samples.

The advantages of using drip as a sampling material for estimating shelf life or sanitary quality of eviscerated poultry are discussed.
The Rabbit as a Source of Experimental Material for Meat Studies
Authors: PAUL PAULINE C.
Published: August 2006

Rabbits were studied to determine the degree of variation among carcasses treated alike, and the time course of development and resolution of rigor as measured by changes in the force required to shear the cooked longissimus dorsi. A technique was developed for obtaining shears perpendicular to the muscle fibers. Carcasses with similar histories were found quite uniform except for measures related to fat content. Cooking losses were related primarily to moisture content rather than fat content. When half carcasses stored 0, 2, 4, 6, 12 or 24 hr at 5°C were compared, the cooking losses were less at 0 and 24 hrs than at the intermediate times. Shear force decreased with each increase of storage time from 2 to 12 hr. The data on pH and shear indicate that rabbit carcasses handled in this manner pass through the development and resolution of rigor within 12 hr.
Oleoresin of Capsicum (Red Chilies)—Some Technological and Chemical Aspects
Authors: TANDON G. L. , DRAVID S. V. , SIDDAPPA G. S.
Published: August 2006

The principal source of the dry chili of commerce in India is Capsicum annuum, variety acuminatum. The oleoresin capsaicin, which is the alcoholic fraction of the ether extract of chilies, is the active ingredient of several essences and medicinal preparations from chilies. In the local variety used, the pericarp, which constitutes nearly 40% of the whole chilies, contains nearly 89% of the capsaicin, while the seeds contain 11%, and the stems only traces of it. Ether is one of the best solvents for extraction of the oleoresin by the percolation method. Since the pericarp contains considerably less fatty oil than the seeds, use of the pericarp for extraction obviates the difficulty of separation of the fatty oil from the oleoresin. The fatty oils, obtained separately from whole chilies and from the seeds, which are bland in taste, have higher acid and iodine values, but lower saponification values, than mustard or groundnut oils. Physicochemical standards have been determined for the oleoresin, fatty oil from whole chilies and fatty oil from the seeds alone.
Reactions Involved in Sulfite Bleaching of Anthocyanins
Authors: JURD LEONARD
Published: August 2006

The bleaching of anthocyanins by sulfur dioxide is a reversible process that does not involve hydrolysis of the 3‐glycosidic group, reduction of the pigment, or addition of bisulfite to a ketonie, chalcone derivative. In sulfite decoloration the reactive species is the anthocyanin carbonium ion (R+). The experimental evidence indicates that this simply reacts with a bisulfite ion to form a colorless chromen‐2 (or 4)‐sulfonic acid (R‐SO3H), similar in structure and properties to an anthocyanin carbinol base (R‐OH).
Biochemical Properties of Pork and Their Relationship to Quality I. pH of Chilled, Aged and Cooked Muscle Tissuea,b
Authors: KAUFFMAN R. G. , CARPENTER Z. L. , BRAY R. W. , HOEKSTRA W. G.
Published: August 2006

Values for pH were obtained from the chilled, aged, and cooked loin and ham muscles originating from 439 pork carcasses. Muscle pH was compared to a number of objective and subjective measurements related to the qualitative and quantitative values of pork products. Increased muscle acidity was associated with pale, soft tissues, which yielded higher percentages of expressible juice. Chilled‐muscle pH was associated with the pH of aged and cooked muscles, and there was also a positive relationship between the pH values of different muscles within each carcass at any stage of comparison. Dark, dry, firm muscle tissue exhibiting a relatively high pH, shrank less during curing and cooking and was more juicy and tender than pale, soft watery muscle tissue of low pH. Regardless of muscle acidity, the curing process raised all palatability ratings to a comparable and acceptable level; therefore it was concluded that the primary importance of a higher pork muscle pH, especially for hams, is its association with less shrinkage during processing.
The Determination and Contents of α‐ and γ‐Tocopherols in Margarine
Authors: LAMBERTSEN G. , MYKLESTAD H. , BRAEKKAN O. R.
Published: August 2006

Methods are described for the determination of α‐tocopherol and γ‐tocopherol in margarine by column and paper chromatography and spectrophotometric measurement of the tocopherols. Thirty‐seven samples of Norwegian margarine, average values 52 μg/g α‐tocopherol and 89 μg/g γ‐tocopherol, together with 18 samples from other European countries, were assayed. Ten of the samples were further assayed after 7 months of storage, and showed average losses of 20% of α‐tocopherol and 14% of γ‐tocopherol. Analyses carried out on 8 samples of hydrogenated fats gave tocopherol values up to the level of original oils, indicating that the hydrogenation step itself does not destroy the tocopherols. Lastly, 7 samples of mixed fat for margarine production were assayed, and gave values somewhat higher than those calculated from the margarine values, indicating some loss during margarine production.
Effect of Lipid Content on Protein‐Sodium Linolenate Interaction in Fish Muscle Homogenates
Authors: ANDERSON MARGAKET L. , STEINBERG MAYNARD A.
Published: August 2006

A species difference in reactivity of fish muscle proteins toward sodium linolenate in muscle homogenates is demonstrated. The proteins of muscle having higher lipid content show greater stability. Sodium linolenate uptake by natural lipids, resulting in competition between lipids and protein for added sodium linolenate, is suggested. The significance of these findings in terms of a possible in situ relationship of lipid hydrolysis to protein denaturation in frozen stored fish muscle is discussed.
The Influence of Chemical Additives on the Heat Resistance of Salmonella typhimurium in Liquid Whole Egg
Authors: LATEGAN PIETER M. , VAUGHN REESE H.
Published: August 2006

The heat resistance of Salmonella typhimurium in liquid whole egg at pH 5.5 and 55°C was reduced significantly by a number of chemical additives. Of these, the most effective were β‐propiolactone, ethylene oxide, and butadiene dioxide. Additional advantages of ethylene oxide and β‐propiolactone were the elimination of S. typhimurium from heavily inoculated whole‐egg slurry during storage at 0°C and a markedly increased lag phase of growth of the test organism in egg incubated at 30°C. Butadiene dioxide, although not tested at 0°C, was most effective in reducing heat resistance at pH 5.5 and 55° C, and also greatly increased the lag phase of the test organism at 30° C. Unfortunately, this latter compound is carcinogenic to mice.

Acetic or lactic acid, used to lower the pH of liquid whole eggs, decreased the heat resistance of S. typhimurium more effectively than did hydrochloric acid, especially at pH 5.5 arid 6.0. Formic and propionic acids also were more effective than HCl when all were tested at pH 5.5. Differences in degree of dissociation between hydrochloric and the organic acids are thought to account, in large measure, for these observations.
Voges‐Proskauer‐Positive Yeasts Isolated from Frozen Orange Concentratea
Authors: MURDOCK D. I.
Published: August 2006

Seven Voges‐Proskauer‐positive yeasts were isolated from 290 cans of frozen concentrated orange juice representative of the 1962 season's pack. Taxonomy studies of 4 isolates showed the presence of 2 strains of Saccharomyces. Each of the identified yeast strains grew and produced diacetyl in 12° Brix orange juice and 42° Brix orange concentrate, then subsequently removed it. Reagent‐grade diacetyl added to a 42° Brix sucrose solution inoculated with one of the test organisms was reduced 95% after 7 days at room temperature. The metabolic process involved in removing diacetyl from a product by yeast is not known.
Influence of Buffers and pH on the Thermal Destruction of Spores of Bacillus megaterium and Bacillus polymyxaa
Authors: WALKER HOMER W.
Published: August 2006

Spores of Bacillus megaterium 1A28 and B. polymyxa 1A39 were heated at 100°C in buffers adjusted to different pH values. Generally, recovery of survivors was greatest in the neutral zone. Variations in recovery of survivors were attributable to the organism, buffer constituents, and pH of the buffer system. Use of different phosphate salts had no influence on destruction; stability was greatest in a range of .005—.050M phosphate. Citrate, phthalate, or ammonium ion in the buffer usually reduced heat resistance of the spores below that demonstrated in phosphate buffer.
Chlorophyll Catalysis of Fat Peroxidationa
Authors: HALL J. L. , MACKINTOSH D. L.
Published: August 2006

Peroxide apparently occurring in freshly prepared sausage was traced to the catalytic effect of chlorophyll in the sage after fat extraction. The extracts were exposed to ordinary laboratory illumination a day before analysis. No peroxide appeared in extracts of the pork fat alone, nor in extracts of the sage alone. But mixtures of fat extract with sage extract developed peroxide. Extracts of green leafy material from other species and purified chlorophyll likewise developed peroxide with fat extracts. This effect is ascribed to the porphyrin structure. Extracts containing fat and chlorophyll should be kept in the dark until peroxide estimation.
Changes in Concentrated Milk During Frozen Storagea
Authors: NICKERSON THOMAS A.
Published: August 2006

Prefreezing treatments greatly influence the physical stability of concentrated milk during frozen storage. Treatments that tend to retard lactose crystallization extend storage life. Agitation or cooling procedures that induce nucleation accelerate destabilization, as does the presence of foreign nuclei. Effluent diagrams from a DEAE column show changes in the casein fractions and in β‐lactoglobulin. The mechanism of protein insolubilization during frozen storage appears to be more complex than previously suggested.
Some Aspects of the Action of Tylosin on Clostridium Species PA 3679
Authors: POOLE G. , MALIN B.
Published: August 2006

Spores of PA 3679 were derived from vegetative cells made resistant to an initial 4.0 ppm tylosin. Rate of germination of PA 3679 spores, either from the original sensitive stock or from a resistant stock, is not affected by tylosin. Vegetative cells of PA 3679 arising from germination and subsequent outgrowth of the resistant cells are killed by 0.8–0.9 ppm of residual tylosin. This is to he compared with 0.05–0.25 ppm initial tylosin required to kill sensitive cells. The residual level of tylosin in sterile spore‐recovery media is dependent on the initial tylosin concentration and the medium.
Survival of Clostridium perfringens in Frozen Chicken Gravya
Authors: STRONG DOROTHY HUSSEMANN , CANADA JAMES C.
Published: August 2006

The effect of freezing Clostridiuna perfringens in chicken gravy was examined. Two means were used in inoculating the gravy: 1) inoculum‐ of C. perfringens was allowed to grow in the gravy for 6 hr; and 2) spores produced in Ellner's medium and dried on sterile soil were added to the gravy. In both cases, the gravy was then held in the frozen state (–17.7°C) for 180 days. When growth was permitted in the gravy, a maximum of 4.29% and 3.69% of viable cells survived for 90 and 180 days, respectively. When spores dried on soil were added to the gravy, maximum survival was 37.9% at 90 days and 10.9% at 180 days.
The Determination of the Tensile Strength of Fluid Food Materials
Authors: CHARM STANLEY E.
Published: August 2006

The tensile strength of fluid food materials is a rheological property which is rarely considered, although it may play a role in texture and coating behavior in certain eases. It is possible to measure the tensile strength of the fluid by forcing it slowly downward through a vertical tube which is less than the critical diameter. The fluid column will break when the weight of the column divided by the cross‐sectional area of the column equals the tensile strength of the fluid. The tensile strength of ketchup, tomato paste, and mayonnaise was measured and found to be about twice the shear strength. Tube diameter had no effect on measured tensile strength provided it was less than the critical diameter.
A Comparison of Normal and Stressed‐Time Conditions on Scoring of Quality and Quantity Attributes
Authors: OUGH C. S. , SINGLETON V. L. , AMERINE M. A. , BAKER G. A.
Published: August 2006

Data reported indicate that tasting under a time stress may he slightly advantageous when subjects are asked to judge a quantity difference; hut that for judging quality differences, tasting with no time stress is superior for most tasters. The Brunswick probabilistic theory is discussed in the light of these experiments, which tend to verify applicability of the theory. The linear dependency of tasters' use of scales for quantity evaluation, and to some extent for quality evaluation (if not under stress), is demonstrated.
Effects of Sample Sequence on Food Preferencesa,b
Authors: EINDHOVEN JAN , PERYAM DAVID , HEILIGMAN FRED , HAMMAN J. W.
Published: August 2006

Hedonic‐scale preference tests were run with four types of meat. Each one compared two non irradiated (“good”) samples with two irradiated (“poor”) samples. Three effects were demonstrated: a) position effect (the later samples in the series were rated lower); b) contrast effect (serving “good” samples first lowered the ratings for “poor” samples); and c) convergence effect (serving “poor” samples first lowered the ratings for “good” samples). Contrast and convergence effects were shown to be independent of position effect.
Effect of Other Flavor Components on the Perception of Diacetyl in Fermented Dairy Products
Authors: BENNETT GRACE , LISKA B. J. , HEMPENIUS W. L.
Published: August 2006

The effect of fat, pH, and volatile acids on the perception of diacetyl was investigated. At the normal pH of skim milk or cream the threshold for diacetyl was 0.01 ppm. At pH 5.0 the threshold in skim milk was 0.2 ppm, and at pH 4.4 the diacetyl threshold in cream was 0.05 ppm. The fat content of cream probably suppresses the acid effect. The presence of propionic acid did not lower the threshold of diacetyl in sour cream. Formic acid lowered the threshold slightly, whereas acetic acid and acetaldehyde lowered it considerably.
Lipid Fractions of Chicken Broiler Tissues and Their Fatty Acid Composition
Authors: MARION J. E. , WOODROOF J. G.
Published: August 2006

Lipids extracted from chicken breast muscle, thigh muscle, and skin tissue were fractionated by thin‐layer and column chromatography. Breast muscle lipids were highest in the proportions of phospholipids to neutral lipids, followed by thigh muscle and skin tissue lipids. Gas‐liquid chromatography analysis of the fatty‐acid‐containing fractions showed that phospholipids contained higher levels of 18‐carbon saturated, and 20–24‐carbon unsaturated fatty acids than triglycerides. Triglycerides contained higher levels of 18‐carbon mono‐ and diunsaturated fatty acids than phospholipids. The minor lipids were generally between the phospholipids and triglycerides in their proportion of saturated to unsaturated fatty acids. The fatty acid composition of similar lipid fractions did not vary appreciably with tissue location: only the proportion or level of lipid fractions varied in different tissues.
Effect of EDTA and pH on Properties of Freeze‐dried Pork Muscle I. Effect of pH and Magnesium and Calcium Ions on Freeze‐dried Myofibrils
Authors: WISMER‐PEDERSEN J.
Published: August 2006

To study the effect of pH and divalent cations such as Mg and Ca on rehydration of freeze‐dried meat, a model system of freeze‐dried myofibrils was designed. The fibrils were dried at pH 5.4, 6.0, and 7.0, with and without addition of Mg and Ca, in the concentrations found in meat. The freeze‐dried fibrils were rehydrated after homogenization in the rehydrating solution; and by diffusion of the solution into the dried fibril mass. When the fibrils were homogenized the cations increased the water‐holding capacity of the sedimented fibrils. An increase in the water‐holding capacity with higher pH was apparent only after the cations were added. When the fibrils were rehydrated through diffusion, the cations decreased the hydration. Increased hydration capacity with higher pH was found with and without the cations.
The Effect of Selected Anions of Potassium Salts on the Viscosities of Lambda‐Carrageenan Dispersions
Authors: ZABIK MARY E. , ALDRICH PEARL J.
Published: August 2006

Viscosity readings with three rates of shear for each of six time intervals were obtained for 0.5% dispersions of lambda‐carrageenan in de‐ionized water and in solutions of increasing concentrations of CH3COOK, KBr, K2CO3, KCl, K3C3H5O7, KNO3, K3C2O4, K3PO4, and K2SO4. The addition of any of these salts to the water in which lambda‐carrageenan was dispersed caused a highly significant decrease in viscosity. Significant differences also occurred among the viscosity readings for lambda‐carrageenan dispersed in different concentrations of one salt; however, the same concentrations of the different salts did not show comparable effects on the reduction of carrageenan viscosity. No significant differences occurred among viscosity readings for carrageenan dispersed in the various potassium salts at the 0.05N level of concentrations nevertheless, differences did occur at both the 0.10N and 0.20N levels of concentration. All solutions tested showed significant differences among viscosity readings due to rate of shear. Differences were minimal among viscosity values attributable to aging time of the dispersions.
Soybean Saponins. IV. The Effect of Proteins on the Inhibitory Activity of Soybean Saponins on Certain Enzymes
Authors: ISHAAYA ISAAC , BIRK YEHUDITH
Published: August 2006

Soybean saponins were found to inhibit, to a certain extent, cholinesterase and the proteolytic activity of chymotrypsin, trypsin, papain, and Tribolium castaneum larval midgut enzyme solution. It has been shown that this nonspecific inhibition results from a protein (i.e., enzyme) saponin interaction, since pre‐incubation of the saponin with various proteins prior to enzyme‐substrate interaction could abolish the inhibitory effect of the saponins.
Papaya Pectinesterase inhibition by Sucrose
Authors: CHANG L. W. S. , MORITA L. L. , YAMAMOTO H. Y.
Published: August 2006

Pectinesterase (PE) was inhibited by sucrose at the same concentrations that delayed gelation of papaya purée. The inhibitory effect was linear with sucrose concentration throughout the range investigated (up to 50% sucrose). Conditions for optimum PE activity, pH 7.5 and 0.21M NaCl, were not affected by inhibitory concentrations of sucrose. Evidence was obtained against competitive inhibition, transferase activity, and an effect on the binding of PE as possible mechanisms for inhibition. Other sugars tested, including glucose, maltose, and corn syrups of varying degrees of hydrolysis, as well as glycerol were also inhibitory.
Volatiles from a Commercial Pea Blancher. Mass Spectral Identification
Authors: RALLS JACK W. , McFADDEN W. H. , SEIFERT RICHARD M. , BLACK D. R. , KILPATRICK P. W.
Published: August 2006

Volatile components from the steam above peas in a commercial blancher were isolated by adsorption on charcoal, freeze‐drying of the charcoal, solvent extraction, and distillative concentration. The concentrate was further fractionated by distillation and gas chromatography. Ethanol and dimethyl sulfoxide were most abundant. The latter compound formed by the oxidation of dimethyl sulfide adsorbed on the charcoal. The less abundant components of the concentrate fractions were identified by capillary‐column gas‐chromatography fast‐scan mass spectrometry. The most novel group of minor components thus identified was the diethyl acetals of C1‐C6 aldehydes. It was not possible to determine from model experiments if the acetals were original components of the blancher steam or artifacts of the isolation. A control concentrate from unexposed charcoal and purified solvent differed quantitatively and qualitatively from the blancher steam concentrate.
Isolation and Evaluation of the Saccharide Components of Starch Hydrolysates. II. Evaluation
Authors: HOOVER W. J. , NELSON A. I. , MILNER R. T. , WEI L. S.
Published: August 2006

Oligosaccharides of DP 3–10 were evaluated for their properties of density, refraetive index, viscosity, optical rotation, reducing power, and infrared absorption characteristics. Tables of data were developed giving the expected values of each property for each oligosaccharide.

As expected, density, refractive index, viscosity, optical rotation, and reducing power were related to the molecular weight of the sugars. The degree of the effect of molecular weight on each of these properties was established.
Volatile Constituents of Black Pepper. III. The Monoterpene Hydrocarbon Fraction
Authors: WROLSTAD R. E. , JENNINGS W. G.
Published: August 2006

The monoterpene hydrocarbons of black pepper oil were isolated both by vacuum distillation and by thin‐layer chromatography. The following compounds were separated by gas chromatography and identified by infrared and ultraviolet spectroscopy: α‐pinene, β‐pinene, sabinene, β‐carene, limonene, and p‐cymene. There is evidence for the presence of a‐thujene, α‐phellandrene, myrcene, β‐phellandrene, y‐ter‐pinene, and terpinolene. The monoterpenes isolated by thin‐layer chromatography also contained small quantities of α‐terpinene and greater quantities of γ‐terpinene, p‐cymene, and terpinolene.
Evaluation of Factors Affecting the Determination of Nitrogen in Soya Products by the Biuret and Orange‐G Dye‐Binding Methods
Authors: POMERANZ Y.
Published: August 2006

Nitrogen content of soya protein was determined by a modification of the biuret method in which protein extraction and color development occur simultaneously in an alkaline copper tartarate solution and by the orange‐G dye‐binding method. Percentage of total nitrogen content extracted into the solution increased as total nitrogen content increased. Amount of extracted nitrogen was reduced in coarsely ground or severely heated samples. In finely pulverized and untoasted samples, correlation of Kjeldahl protein with the biuret method of protein estimation was 0.985, and with the dye binding method was 0.989.
Salmonella Derby Contamination of Eggs from Inoculated Hens
Authors: MELLOR D. B. , BANWART G. J.
Published: August 2006

Twelve hens were inoculated weekly for 11 weeks with Salmonella derby in peptone water. Another 12 were fed continuously on feed which had been contaminated with Salmonella derby. Another group of birds served as controls. Both the shell surface and interior of 2 eggs per bird each week were examined for salmonellae. Chicks hatched from 5 selected hens were also examined for salmonellae. Neither the shells nor the egg meats from the 622 eggs sampled yielded positive S. derby cultures during the trial. The feces of 2 birds receiving contaminated feed, and of 4 birds receiving the weekly inoculation contained the S. derby. S. derby was not recovered from any of the hens upon sacrifice or in any of the chicks from these hens.
Cranberry Anthocyanins
Authors: ZAPSALIS C. , FRANCIS F. J.
Published: August 2006

The red pigments from Early Black cranberries were extracted with methanol, purified by lead acetate precipitation and polyamide columns, separated on silicic acid columns, and crystallized. The four pigments were identified as cyanidin‐3‐monogalactoside, peonidin‐3‐monogalactoside, cyanidin‐3‐monoar‐abinoside, and peonidin‐3‐monoarabinoside based on the following evidence: Rt data in three solvents, fluorescence, sugar‐aglycone ratios, formic acid and hydrogen peroxide hydrolysis, and spectral data. The absorption coefficients in ethanol‐0.1/N hydrochloric acid (85:15) were also determined.
Changes in the Anthocyanin Pigments of Raspberries During Processing and Storage
Authors: DARAVINGAS GEORGE , CAIN R. F.
Published: August 2006

The effect of ingoing sirup concentration, various headspace atmospheres, and time and temperature of storage on the retention of the anthocyanin pigments in canned red and black raspberries was determined. The four anthoeyanins of red raspberries and the three anthocyanins of black raspberries were separated by column chromatography and analyzed spectrophotometrically. The anthocyanins appeared to be similar in the two species as determined by paper chromatography. The absorption maximum of the pigments shifted during storage. Prolonged times and higher temperatures of storage both significantly reduced the recoverable anthocyanins. Increased concentration of ingoing sirup and the presence of oxygen resulted in greater pigment destruction.
The Precursors of Chocolate Aroma: The distribution of free amino acids in different commercial varieties of cocoa beans
Authors: ROHAN T. A. , STEWART T.
Published: August 2006

A study of the distribution of the free amino acids in different commercial varieties of cocoa beans revealed differences which might account, at least in part, for the acknowledged variations in aroma and flavor of the products obtained from these raw materials.
Structure of the Carotenoid Neoxanthin
Authors: CURL A. LAURENCE
Published: August 2006

The products formed on reaction of neoxanthin with hydrochloric acid in methanol and in acetone indicate that neoxanthin is 3,3′,5′‐trihydroxy‐5′6′‐dihydro‐5,6‐epoxy‐beta‐carotene. The tertiary 5′‐hydroxyl group reacts in a similar manner to the allylic 3′‐hydroxyl group in lutein.
The Use of Reflectance Spectrophotometry for the Assay of Raw Meat Pigments
Authors: STEWART MARGARET R. , ZIPSER MARELYNN W. , WATTS BETTY M.
Published: August 2006

The literature on reflectance spectrophotometry, as it applies to meat pigments, is critically reviewed, and improved methods are suggested for determination of total pigments and of the percent metmyoglobin from reflectance data on raw meat. The suggested method for total pigment was based on reflectivity of the meat samples at 525 mμ, the isobestic point for myoglobin, oxymyoglobin, and metmyoglobin. The reflectivity data, when calculated as the corresponding ratios of the absorption coefficient K to the scattering coefficient S were linearly related to total pigment extract from the meat with acidified acetone. K/S values of pigment‐free (peroxide‐treated) samples were obtained as a base line. Lowering the pH of the meat decreased the K/S value. This was attributed to changes in texture which increased S. Metmyoglobin was determined from the ratio K/S 572 mp/K/S 525 mμ. Limiting values for the ratio were established for meat containing 100% and 0% metmyoglobin, and a linear relation was assumed between the ratios and intermediate amounts of metmyoglobin.
Viscometric Behavior of Tomato Concentrates
Authors: HARPER J. C. , EL SAHRIGI A. F.
Published: August 2006

Tomato purées have a pseudoplastic non‐Newtonian behavior which agrees reasonably well with the power‐law model over substantial ranges of shear rates. Behavior is more consistent at higher shear rates (above 300 or 400 see‐1), with values af the power‐law exponent in the neighborhood of 0.4 over a wide range of concentrations and temperatures. Both concentration and temperature primarily affect the power‐law coefficient rather than the exponent. Viscosity correlations in the lower shear‐rate region are uncertain because of somewhat variable behavior, probably resulting from yield stresses, wall effects, and time dependency. Apparent viscosities are much higher in concentrates produced by direct evaporation than in concentrates made by centrifuging out the insoluble solids, concentrating the serum, and then reconstituting.
Food Crushing Sounds: Comparisons of Objective and Subjective Data
Authors: DRAKE BIRGER K.
Published: August 2006

The sounds produced when certain foodstuffs were chewed were tape recorded, and the amplitude of frequency‐filtered or total sound was measured from the recordings. On the same occasions, the subjects' opinions about toughness/tenderness or about loudness were noted. Some correlations between objective and subjective data obtained in this way are presented and discussed.
Role of Pectin Methylesterase in Firmness of Canned Tomatoes
Authors: HSU CECILIA P. , DESHPANDE S. N. , DESROSIER N. W.
Published: August 2006

Four sets of eight tomatoes were subjected to four blanching times of 30, 60, 90, and 120 set at 100°C. Two fruits in each set were also subjected to holding times of 5, 10, 15, and 20 min between the blanching and exhausting operations. Pectic substances were determined as water‐soluble, ammonium‐oxalate‐soluble, and dilute‐hydrochloric‐acid‐soluble fractions. The methoxyl content of each fraction was also determined. Firmness was determined by objective measurements. The 30‐see blanching treatment yielded the firmest tomatoes. These fruits were also characterized by the highest content of ammonium‐oxalate‐soluble pectin. The activity of pectin methylesterase was highest in treatments consisting of 30 see of blanching and a lo‐min holding time. The activity of pectin methylesterase seemed to be greatly suppressed after 90 set of blanching.
A Comparison of the Volatile Fractions from Cured and Uncured Meat
Authors: CROSS C. K. , ZIEGLER P.
Published: August 2006

Gas chromatographic examination of the volatiles of cured and uncured ham showed that hexanal and valeraldehyde were present in appreciable quantities in the uncured product hut were barely detectable in the volatiles of the cured meat. The differences were less pronounced in the contents of hutyraldehyde, propionaldehyde, and acetaldehyde between cured and uncured ham volatiles, though these aldehydes tended to be more prevalent in the uncured ham. The branched‐chain aldehydes (isobutyraldehyde, isovaleraldehyde, 2‐methyl‐hutyraldehyde) occurred to the same extent in both meats. Acetone was found to represent a major carhonyl constituent of the volatiles in both cured and uncured ham. The sulfur‐containing fractions of the volatiles from both meats were found to comprise hydrogen sulfide and methanethiol.
Fractionation and Study of Compounds in Wood Smoke
Authors: PORTER R. W. , BRATZLER L. J. , PEARSON A. M.
Published: August 2006

Hard‐maple sawdust was sifted on a con‐trolled‐temperature hotplate for smoke production. The acids, total phenols, and carbonyl compounds were determined on the steam‐volatile and non‐steam‐volatile portions of both whole smoke and the vapor phase. Most of the compounds in these groups were found to be steam‐volatile.

Several steam‐volatile monocarboxylic acids and monocarbonyl compounds were isolated and identified from smoke. The C1–C10 acids were found to be present in whole smoke, with the C1–C10 acids occurring in the greatest concentrations. Only C1–C10acids were found in the vapor phase of the smoke. The following monocarbonyls were identified in the steam‐volatile portion of whole smoke: 2‐pentanone, valeraldehyde, 2‐butanone, butanal, acetone, propanal, crotonaldehyde, and ethanal. In addition, tentative identification of isovalderaldehyde and methanal was made on the basis of a comparison of chromatographic behavior and absorption spectra of the known and unknown compounds.