bluuebunny/crossref_metadata_2025 huggingface dataset:
Anthocyanin Pigments in Trousseau Grapes
Authors: CARRENO‐DIAZ RAFAEL , LUH B. S.
Published: August 2006

SUMMARY: The anthocyanin pigments in Trousseau grapes were extracted with 0.1% HCI in methanol, purified with Dowex 50 WX 4 cation exchange resin in the hydrogen form, and further purified by paper chromatography. Identificaton of the pigments was based on R1 values in various solvents, partial acid hydrolysis, sugar moiety, alkaline degradation, fluorescence under ultraviolet radiation, color reactions, and absorption spectra in the visible region. Shown to be present in the grapes are petunidin 3‐mono‐ glucoside, cyanidin 3‐monoglucoside, malvidin 3‐monoglucoside, and peonidin 3‐monoglucoside. Based on photodensitometric measurement, malvidin 3‐monoglucoside was present in largest amount (49.8%), followed by peonidin 3‐monoglucoside (36.9%), cyanidin 3‐monoglucoside (8.75%), and petunidin 3‐monoglucoside (4.55%). The identification of all the anthocyanins as monoglucosides supports the classification of Trousseau as a cultiva of Vitis vinifera.
Analysis and Significance of Tyramine in Foods
Authors: SEN N. P.
Published: August 2006

SUMMARY—The tyramine levels in different varieties of cheeses, alcoholic drinks, and other foods were determined. Many of the food samples, analyzed by an existing fluorometric method, contained large amounts (up to 2.2 mg/g) of tyramine. Synephrine and octopamine, although rarely present in food, interfered with the fluorometric analysis. A gas chromatographic method was developed in which tyramine was extracted from foods and then analyzed as its trifluoroacetyl derivative using an electron capture detector. The gas chromatographic method was more sensitive and specific than the fluorometric method, and it permitted detection of 0.1–0.2 nanogram tyramine even in the presence of synephrine and octopamine.
Effect of Preirradiation Quality of Eviscerated Haddock on Postirradiation Shelflife of Fillets
Authors: AMPOLA V. G. , RONSIVALLI L. J.
Published: August 2006

SUMMARY— Radiopasteurization is an effective means of preserving haddock fillets of varying marketable quality. While results show that the postirradiation shelf life was a function of the preirradiation quality, they also indicate that there was an economic benefit from irradiating the fillets cut from fish as old as 13 days after catching.
Gas Chromatographic Analysis of Head‐Space Vapors to Identify Micro‐Organisms in Foods
Authors: GUARINO PHILIP A. , KRAMER AMIHUD
Published: August 2006

SUMMARY— Gas‐liquid partitioning of head‐space vapors offers possibilities as a quality control procedure, permitting rapid identification of certain bacteria of sanitary and public health significance in foods

Representative organisms of the following genera were studied: Escherichia, Salmonella, Citrobacter, Enterobacter, Proteus, Alkaligenes and Pseudomonas. The head‐space vapors over synthetic broth cultures were analyzed by gas chromatography in an effort to obtain reproducible patterns differentiating the bacteria. Selected food materials were inoculated with two cultures (Salmonella and Enterobacter) and, after storage at 5°C, the foods were examined by the chromatographic procedure.

Analysis of head‐space vapors over dextrose fermenting bacterial cultures by gas‐liquid partitioning produced chromatographic patterns differentiating members of the family Enterobacteriaceae. Two food materials inoculated with test organisms evidenced presence of Salmonella and Enterobacter when submitted to analysis. A third food material was initially contaminated with a mixed flora; gas chromatographic analysis indicated the presence of members of the family Enterobacteriaceae.

It is concluded that gas chromatographic analysis of head‐space is a reproducible method and can be applied to routine microbiological examination of foods.
A “Cold Shortening” Effect in Avian Muscle
Authors: SMITH M. C. , JUDGE M. D. , STADELMAN W. J.
Published: August 2006

SUMMARY— Experiments were conducted to determine the effect of post‐mortem temperatures between 0 and 20°C on the degree of shortening in isolated pectoralis major muscles of chickens and turkeys. A “cold shortening” effect in these muscles is described and compared to post‐mortem pH, average sarcomere length of isolated myofibrils, and relative solubility of myofibrillar and sarcoplasmic proteins.

The degree of muscle shortening at each temperature after various periods post‐mortem indicated that shortening was essentially complete after 3 hr in chickens and 5 hr in turkeys. Shortening in muscles stored at 0°C was significantly greater (P < .01) than in the 12–18°C temperature range. Shortening was greatest in muscles stored at 20°C. The degree of gross shortening observed was directly related to the average sarcomere length of isolated myofibrils. Post‐mortem decline in pH was not significantly correlated (P > .05) with shortening. Extractability of myofibrillar and sarcoplasmic proteins after 5 hr at either 0 or 16°C was determined and found to be unrelated to the degree of post‐mortem shortening.
Tomato Volatiles: Effect of Variety, Processing and Storage Time
Authors: NELSON P. E. , HOFF J. E.
Published: August 2006

SUMMARY— Volatile components of three varieties of tomatoes processed in plain tin and enamel can linings at 0, 1, 4 and 8 months storage time were determined. A recently developed extraction method was used for separation and collection of volatiles free of moisture. This method allowed the study of small quantities of materials in a reasonable time. Multiple sampling of the vapor aliquots permitted qualitative and quantitative analysis.

The greatest qualitative and quantitative differences in volatile composition were noted between the raw and heat processed samples. Methyl sulfide which was absent in the fresh fruit was formed during the heat process. The concentrations of acetaldehyde, acetone, methanol, and hexanal were significantly altered by processing. Differences between varieties were due to varying quantities of individual constituents but quantitative differences between can lining were less apparent.
Action of Microorganisms on the Peroxides and Carbonyls of Fresh Lard
Authors: SMITH JAMES L. , ALFORD JOHN A.
Published: August 2006

SUMMARY— The effect of 28 microorganisms on the accumulation of hydroperoxides and monocarbonyls in fresh fat has been determined. Pseudomonas ovalis, Micrococcus freudenreichii and two strains of Streptomyces increased the concentration of peroxides; M. freudenreichii also produced an increase in 2‐enals, 2, 4‐dienals, and alkanals. Pseudomonas fragi, Geotrichum candidum, and Candida lipolytica produced an increase in alkanals and methyl ketones. All other cultures either removed the small amount of peroxides and monocarbonyls in fresh fat and prevented any build‐up or had no effect. The ability of microorganisms to oxidatively attack fats was not related to their oxidase reactions or their ability to produce lipase. Differences in oxidative activity on fresh and rancid lard are discussed.
Comparison of Sterile and Inoculated Beef Tissue
Authors: OCKERMAN H. W. , CAHILL V. R. , WEISER H. H. , DAVIS C. E. , SIEFKER J. R.
Published: August 2006

SUMMARY— A surgical isolator technique was developed for obtaining sterile muscle tissue from a beef carcass. This tissue was compared during refrigerated storage with a general inoculum tissue sample, a low level general inoculum sample, a sample inoculated with Pseudomonas and an Achromobacter sample. Protein fractionation revealed a decrease in sarcoplasmic protein for all treatments during storage. An initial rise, followed by a relatively constant value in the myofibrillar fraction, was also observed for all treatments.

The stroma fraction, the nonprotein nitrogen fraction, percent free water, pH and emulsifying capacity of the aseptic and low level inoculated samples remained fairly constant throughout storage. The higher level inoculated samples decreased slightly in stroma protein during storage and increased in nonprotein nitrogen late in the storage period, These same treatments increased in pH, decreased in percent free water and increased in emulsifying capacity (late in storage).
A Sample Bias in the Evaluation of Smoked Frankfurters by the Triangle Test
Authors: WASSERMAN A. E. , TALLEY F.
Published: August 2006

SUMMARY— A taste panel was able to determine the difference between smoked and unsmoked frankfurters, at a statistically significant level, only when the smoked frankfurter was the “odd” sample; non‐significant selections were made with the unsmoked frankfurter as the “odd” sample. Positional differences of the “odd” sample in tasting the three samples did not affect its selection. Determination of difference between two food products by the triangle taste panel test can be affected by the choice of sample for the “odd” sample.
THERMAL INACTIVATION OF ALPHA‐AMYLASE IN VARIOUS LIQUID EGG PRODUCTS
Authors: MURTHY G. K.
Published: August 2006

SUMMARY— The amount of alpha‐amylase enzyme inactivated at the time‐temperature recommended by the U.S. Public Health Service and by the U.S. Department of Agriculture for various liquid egg products was determined. The liquid whole egg, yolk, salted yolk or blended egg was placed in a stainless steel tube 40 in. in length and with an outside diameter of 0.125 in. The ends were closed and heated in a water bath for varying periods of time at different temperatures. The enzyme was assayed by the starch‐iodine reaction method. When heated for 3.5 min, the amount of enzyme inactivated was 41 ± 5% for whole egg at 140°F; 27 ° 3% for yolk at 142°F; 100% for salted yolk at 146°F; 6 ° 2% for sugared yolk at 146°F and 0% for blended egg at 142°F. The D values at the respective temperatures were 19.6, 28.3, 0.68, 153.0 and 5,858 min. Addition of sucrose or Bactodextrin to egg modifies the alpha‐amylase to become stabilized, and addition of sodium chloride modifies the enzyme to become susceptible to heat inactivation. Consideration of thermal inactivation data showed that the activation energy (92 to 132 Kcal mole−1) and entropy of activation (—238 to —313 Cal mole−1 K−1) were both high, indicating that enzyme inactivation will not become appreciable until much higher temperatures are reached. Data obtained on whole egg pasteurized by the commercial type batch and by the laboratory‐type continuous‐flow methods ware compared with those obtained above and were discussed.
INFLUENCE OF ENVIRONMENT ON PALATABILITY OF CARP
Authors: KORSCHGEN BERNICE M. , BALDWIN RUTH E. , ROBINSON JOHN W.
Published: August 2006

SUMMARY— Carp (Cyprinus carpio Linnaeus) were transferred from a river site receiving little industrial effluent (control fish) and from a location receiving effluents from a major municipality (test fish) to a spring‐fed and to a run‐off pond. Holding for as long as 18 days in either pond failed to improve the aroma or flavor of test carp. The over‐all mean score for flavor of control fish was higher (P < 0.05) than for test fish. Mean scores for flavor were higher for carp held in the spring‐fed pond than for those in the runoff pond but this difference was significant (P < 0.05) only for the test fish.
POTATO EXTRACTIVES: EFFECT ON FIRMNESS OF PECTIN JELLIES AND VISCOSITY QF POTATO STARCH PASTES
Authors: ZAEHRINGER MARY V. , CUNNINGHAM HELEN H.
Published: August 2006

SUMMARY— Pectin jellies and potato starch pastes were prepared with aqueous extracts of potato tissue. All jellies containing potato extractives were weaker than distilled water control jellies. Jellies containing extractives from bud tissue were weaker than those containing extractives from stem tissue. Extractives from tubers stored continuously at 38°F weakened the jellies to a greater extent than those from tubers stored at 38°F and conditioned for 1 wk. Jellies containing extractives from boiled tissue were weaker than those prepared with extractives from blanched or steamed tissue. The most viscous pastes were those made with distilled water. In every case, viscosity of pastes containing extractives from raw tissue was less than half that of distilled water pastes. When extractives from blanched, steamed or boiled tissue were used, the viscosity decreased still further. The rigidity of jellies and the viscosity of pastes prepared with deionized extracts were similar to those of jellies and pastes prepared with distilled water. The data suggest that extractives leached from potato tissue increase sloughing of potato tissue during cooking by weakening the pectic materials in the intercellular cement rather than by enhancing the swelling of starch in the cells.
EFFECT OF MICROBIAL GROWTH UPON SARCOPLASMIC AND UREA‐SOLUBLE PROTEINS FROM MUSCLE
Authors: HASEGAWA TADAO , PEARSON A. M. , PRICE J. F. , RAMPTON J. H. , LECHOWICH R. V.
Published: August 2006

SUMMARY– A comparison of starch gel patterns of sarcoplasmic proteins from aseptic and inoculated porcine and rabbit muscles after storage for 0, 8 and 20 days at 10°C indicated that different microorganisms preferentially utilized specific proteins. Pseudomonas fragi showed the greatest amount of proteolytic activity upon the sarcoplasmic fraction, causing extensive breakdown in both rabbit and porcine muscle. Leuconostoc mesenteroides caused extensive alteration in the sarcoplasmic proteins of rabbit muscle, but had less effect upon porcine muscle. Pediococcus cerevisiae exhibited similar action to L. mesenteroides upon rabbit muscle sarcoplasmic proteins, but had no effect upon pig muscle. Micrococcus luteus showed only minor breakdown of rabbit muscle sarcoplasmic proteins, and had no action upon porcine muscle. Both P. fragi and P. cerevisiae caused considerable breakdown of the urea‐soluble proteins in pig muscle and to a lesser extent in rabbit muscle. Neither M. luteus nor L. mesenteroides exerted any measurable proteolytic effect upon the urea‐soluble proteins. Possible implications concerning meat spoilage are discussed.
VARIANT AND INVARIANT PROPERTIES OF THE MITROCHONDRIAL FRACTION ISOLATED FROM RIPENING BANANA FRUIT
Authors: HAARD NORMAN F. , HULTIN H.O
Published: August 2006

SUMMARY– The mitrochondrial characteristics of oxidation of Krebs cycle intermediates, respiratory control by ADP, succinate‐linked oxidative phosphorylation, and overall morphology, and the amount of protein in the fraction did not vary as the ripening of banana fruit progressed. However, stimulation of succinoxidase activity by calcium and succinate‐driven calcium accumulation underwent striking changes as terminal senescence ensued. The results are consistent with observations of the controlled nature of terminal senescence and to the possible involvement of ancillary work performances, such as active transport, with climacteric respiration.
IDENTIFICATION OF CARBONYL AND SULFUR COMPOUNDS FROM NONENZYMATIC BROWNING REACTIONS OF GLUCOSE AND SULFUR‐CONTAINING AMINO ACIDS
Authors: ARROYO P. T. , LILLARD C. A.
Published: August 2006

SUMMARY– Odor evaluations, chemical analyses and the effect of pH on the nonenzymatic browning reaction products between equimolar concentrations of glucose and each of the sulfurcontaining amino acids, methionine, cysteine and cystine, were conducted. None of the 3 mixtures emitted an odor associated with meat. The cystine‐glucose mixture produced no significant aroma, the cysteine‐glucose mixture an odor resembling over‐boiled egg and the methionine‐glucose mixture an objectionable odor associated with boiled potato, the most interesting of the 3 mixtures. The characteristic odor of the last‐named mixture was attributed to mercaptans. Only the methionine‐glucose mixture was affected by an increase in pH.
EFFECTS OF FOUR SPECIES OF BACTERIA ON PORCINE MUSCLE 2. Electrophoretic Patterns of Extracts of Salt‐Soluble Protein
Authors: BORTON R. J. , BRATZLER L. J. , PRICE J. F.
Published: August 2006

SUMMARY– Electrophoresis of 0.6 M KCI extracts of porcine longissimus dorsi muscle revealed little change in the type or number of protein bands found either by starch‐urea or disc‐urea gel electrophoresis. The 0.6 M KCI extracts of muscle samples inoculated with Pediococcus cerevisiae, Leuconostoc mesenteroides and Micrococcus luteus and stored at 2 and 10°C for 20 days did not differ electrophoretically from control samples. Extracts of samples inoculated with Pseudomonas fragi showed a loss in the number of protein bands on starch‐urea gel and disc‐urea gel electrophoresis, indicating this organism exhibited some proteolytic effect upon the myofibrillar proteins.
THE INFLUENCE OF LACTIC CULTURES ON GROUND BEEF QUALITY
Authors: REDDY S. G. , HENRICKSON R. L. , OLSON H. C.
Published: August 2006

SUMMARY– The effects of adding 5 and 10% lactic culture (Streptococcus lactis and Leuconostoc citrovorum) grown in skim milk; 2.5, 5, 10, and 20% lactic cultures grown in 20% milk solids; 1 and 2% frozen concentrated lactic cultures; lactic acid to pH 5.0 and 4.5; and 2.5, 5, and 10% skim milk to ground beef stored at refrigeration temperature (7°C) were studied in the 6 preliminary trials. Results obtained were used to formulate the principal investigation. The influence of 10% lactic culture and 10% lactic culture plus 450 ppm of ascorbic acid were tested in 5 replicate trials for the principal investigation. Cultures used in the replicate trials were grown in 20% milk solids. CVT (crystal violet tetrazolium) counts for gram‐negative bacteria, pH, VNC (volatile nitrogen content), and organoleptic observations were evaluated. Data from the preliminary study indicated a profound inhibitory action of the lactic cultures on the growth of the inherent gram‐negative bacteria in ground beef. The addition of 10% lactic culture grown in 20% milk solids was effective in preventing aerobic growth. The addition of pure lactic acid inhibited microbial growth, but caused an undesirable color and aroma. Frozen concentrated cultures required 1% lactose to inhibit the growth. The CVT count in the uncultured meat significantly increased (P < .01) as the storage time progressed. Cultured meat did not exhibit a significant increase in CVT count until 7 days of storage. The pH of the cultured meat significantly declined (P <.01) whereas the uncultured meat indicated a significant increase in pH (P < .01) during storage. VNC in the uncultured meat was significantly higher (P <.01) than in the cultured meat. Cultured meat with 450 ppm of ascorbic acid was consistently preferred for flavor, aroma, and when color was compared with the uncultured meat and the meat with culture alone.
THE NITRATE DETINNING REACTION IN MODEL SYSTEMS
Authors: FARROW R. P. , LAO N. T. , KIM E. S.
Published: August 2006

SUMMARY– As part of a coordinated research program on internal can corrosion, the action of nitrates on tinplate was studied in model systems simulating foods of varying acidities. Detinning rates were measured in citrate buffered nitrate solutions ranging in pH from 3.0–7.0. At pH values less than about 5.2–5.5 the detinning is extremely rapid, with slower rates at higher pH values. Nitrate concentrations of 125 ppm in pH 4 buffers completely detinned cans in about 2 months at ambient temperatures. Ammonia is the principal nitrate reduction product in the pH range of acid products. Nitrous oxide is also produced and acts as an effective detinner at pH 4 and 5. Nitrogen may also be produced at pH 5.
INTEGRAL TECHNIQUES APPLIED TO SUBLIMATION DRYING WITH RADIATION BOUNDARY CONDITION
Authors: McCULLOCH JOHN W. , SUNDERLAND J. EDWARD
Published: August 2006

SUMMARY– An analytical solution is presented for the temperature distribution in a semi‐infinite slab with a radiation boundary condition and sublimating phase front. 2 cases are considered. First, a solution is presented for the transient surface temperature holding the heater temperature constant. Secondly, a solution is presented for the heater temperature variation required to hold the surface at the same prescribed value reached in the first case. The application of this technique to sublimation drying is considered, along with calculations to demonstrate the effect of various parameters on the drying time. For example, a steak 1/2‐in. thick with a porosity of 0.8 can be dried 35% faster if the initial heater temperature is 200 rather than 150°F. In contrast, for the same sample, the drying time is increased by only 15.5% if the initial heater temperature is 250 instead of 200°F. Graphs are included to show how optimum drying rates may be obtained.
BACTERIOLOGICAL ANALYSIS OF FROZEN SHRIMPS. 1. Total Plate Count‐Coliforms and Enterococci in Precooked Frozen Chilean Shrimp
Authors: VIRGILIO R. , GONZÁLEZ C. , MENDOZA SILVIA , AVENDAñO SONIA , MUÑOZ NUBIA
Published: August 2006

SUMMARY– 392 samples of precooked frozen shrimps from 2 Chilean industries (A and B) were analyzed for total bacterial count, conforms and enterococci throughout a period of 8 months. 1‐lb samples of breaded shrimp were received directly from the manufacturers after a freezing period of 10 days at —18δC. Total bacterial count ranged from 104 to 105 organisms perg. Conforms were absent in 65% of the samples from A, and in 40% of those from 8; 89.6% of the samples from A and 50.1% of those from B were bacteriologically acceptable considering a limit of not more than 50 coliforms per g. 98% of the frozen shrimp samples belonging to A contained enterococci, as did 66% of the samples from B. Smaller percentages (17% for A and 54% for B) of acceptable samples are obtained from both industries when 100 enterococci per g is considered as the limit. During the period of observation some sanitary measures were adopted and subsequent coliform counts improved. In plant A working conditions are better and the understanding of bacteriological grounds for the proper handling of food materials has led to the elaboration of a product of consistently better quality. Enterococci counts are in contradiction with coliform counts, since the low‐level coliform samples are rejected on the basis of their enterococcal content. In plant B there is a better correlation between coliform and enterococcal counts. Though not investigated, this may be related to the precooking system employed: steaming in an enclosed conveyor in A versus immersion in boiling sea‐water in B.
CALCIUM POLYPHOSPHATE INTERACTION IN CURING PICKLES AND THE EFFECT OF CALCIUM ON CURED HAM YIELDS
Authors: HEGARTY G. R. , RENDEK R. B. , ZALOUDEK PAMELA
Published: August 2006

SUMMARY– The formation of a calcium polyphosphate precipitate in curing pickles is dependent upon brine strength, brine temperature, tripolyphosphate concentration and calcium concentration. The highest concentration of calcium at which no precipitate is formed under various conditions is referred to as the critical calcium concentration. A series of curves is presented from which the critical calcium concentration can be determined for any practical combination in solution of NaCl, sodium tripolyphosphate and calcium ions. The effect on the critical calcium concentration of temperature, pH and added sucrose was also determined and graphically presented. In some cases, added CaSO4 caused a significant increase in the water holding capacity of cured ground ham, and in no instance did the calcium salt cause a reduction in water‐holding capacity. The yield of fully‐cooked cured hams was not affected by curing with phosphate pickles containing abnormally high levels of CaSO4.
MICROFLORA OF FRESH PORK SAUSAGE CASINGS. 2. Natural Casings
Authors: RIHA WILLIAM E. , SOLBERG MYRON
Published: August 2006

SUMMARY– Aerobic total plate counts on TGE Agar at 28°C varied from a level greater than 30,000 to 59,000,000 microorganisms per gram in salt‐packed natural casings and from 180,000 to 23,000,000 organisms per gram in wet‐packed natural casings. Both salt‐packed and wet‐packed casings supported similar growth patterns in selective media. 38 isolates were identified from the salt‐packed casings and 53 from the wet‐packed. Of the salt‐packed isolates, 60.5% were of the genus Bacillus, 7.9% Pseudomonas, 15.8% Clostridium, 1.6% Micrococcus and 5.3% Gaffkya Those isolates obtained from the wet‐packed casings included 62.3% Bacillus, 7.5% Pseudomonas, 7.5% Clostridium, 7.5% Micrococcus, 5.6% Proteus, 1.9% Lactobacillus and 5.7% unidentified.
TEMPERATURES IN EGG PRODUCT FOAMS DURING VAT PASTEURIZATION
Authors: DICKERSON R. W. , PARKER R. W. , READ R. B.
Published: August 2006

SUMMARY– Most egg products are pasteurized in continuous‐flow equipment, but small quantities are more economically processed in a vat pasteurizer. By insulating itself, the surface foam in the vat process may be below pasteurization temperature for a significant part of the holding time and salmonellae in the foam may survive. Using a 100‐gal vat, we generated foams on 5 egg products and measured foam temperatures during pasteurization. Maximum jacket temperature was held to 160°F and no product burn‐on was observed in the vat. All products were held above their respective pasteurization temperatures for 30 min. The minimum temperature of a 6.5‐in. liquid whole egg foam was below pasteurization temperature for 11 min after start of pasteurization. The delayed heating effect of a 1‐in. foam on sugared yolk (10% sucrose by weight) was 13 min. Yolk and salted yolk (10% salt by weight) foams were below liquid temperature during heating; however, in both cases liquid and foam reached pasteurization temperature simultaneously. Minimum temperature of plain egg white foam (pH 9.0) did not reach pasteurization temperature during the holding period. In vat pasteurization, the holding time begins when the liquid reaches pasteurization temperature, and the holding time should be long enough for both foam heating and pasteurization of foam. Except for egg white, about 15 min was required to heat foam to pasteurization temperature. Adding 15 min for pasteurization of the foam yielded a total holding time of 30 min, with the temperature of pasteurization established on the basis of the 15‐min holding time for the foam as follows: liquid whole egg, 133°F; yolk and yolk blends, 135°F; sugared and salted yolk, 139°F. With egg white, foam heating times were in excess of 30 min, and vat pasteurization, with a holding time of 30 min, was not effective.
RHEOLOGY OF FRESH, AGED AND GAMMA‐IRRADIATED EGG WHITE
Authors: TUNG M.A. , RICHARDS J. F. , MORRISON B. C. , WASTSON E. L.
Published: August 2006

SUMMARY– Rheology of unmixed egg white at 2°C was studied with a narrow‐gapped rotational viscometer over a 20‐fold range of shear rates. For a constant shear rate, egg white consistency decreases with time and approaches an equilibrium value in a few minutes. Flow behavior is pseudoplastic at 2°C between shear rates of 8.1–147 sec‐1 and the shear stress‐shear rate relation is accurately described by the power law and Casson models. The effects of gamma irradiation dose on Haugh unit score and equilibrium shear stress are discussed.
BACTERIA‐INDUCED BIOCHEMICAL CHANGES IN CHICKEN SKIN STORED AT 5°C
Authors: ADAMCIC M. , CLARK D. S.
Published: August 2006

SUMMARY: The effect of psychrotolerant bacteria on the water‐holding capacity as measured by the extract release volume (ERV), pH and protein degradation in chicken skin stored at 5°C was determined using strains of Achromobacter and pigmented and nonpigmented Pseudomonas. All organisms caused a rapid decrease in ERV to about 50% of the original value during the early log phase of growth before development of off‐odor. Changes in pH and content of extractable nitrogenous materials occurred during bacterial growth but were not pronounced until after the count was greater than 108 cells/g of skin and a faint off‐odor was detectable. The content of extractable materials decreased during the early log phase, corresponding to the period of rapid increase in pH; later, during the late log or stationary phases of growth, it rapidly or gradually increased, depending on the organism.
THERMAL BEHAVIOR OF PORCINE COLLAGEN AS RELATED TO POST‐MORTEM TIME
Authors: FIELD R. A. , PEARSON A. M. , KOCH D. E. , MERKEL R. A.
Published: August 2006

SUMMARY: DTA (differential thermal analysis) thermograms of epimysial connective tissue from normal and low quality porcine muscle were compared at 0 and 24 hr post‐mortem. In addition, the melting characteristics of intramuscular collagen were determined at 0 hr post‐mortem. In all tissues studied, collagen from low quality muscle consistently gave slightly lower peak melting points than that from normal muscle. Epimysial collagen had a significantly (P < .05) lower peak melting point at 24 hr than at 0 hr post‐mortem (64.24 vs. 65.77°C). Using epimysial collagen, a significantly (P <.01) greater proportion of the total melting range occurred at lower temperatures at 24 hr post‐mortem as compared to 0 hr (4 1.1 vs. 30.9%). The thermal behavior of intramuscular collagen at 0 hr post‐mortem was similar to that of epimysial collagen at 0 hr, but peak melting temperatures were slightly higher for intramuscular connective tissue.
ENZYMIC OXIDATION OF SIMPLE DIPHENOLS AND FLAVONOIDS BY ORANGE JUICE EXTRACTS
Authors: BRUEMMER JOSEPH H. , ROE BONGWOO
Published: August 2006

SUMMARY: Extracts of orange juice vesicles oxidized p‐hydroquinone (HQ) and o‐dihydroxyphenylalanine (DOPA) with O2. Most of the oxidase activity was associated with a particulate fraction that sedimented at 100,000 × g. Sonic disruption of the particulates followed by chromatography on DEAE‐cellulose increased specific activities with both substrates. The partially purified enzyme oxidized numerous naturally occurring o‐diphenols and o‐methoxyphenols. Acidic media below pH 4 and heating above 70°C destroyed most of the oxidase activity. KCN, diethyl‐dithiocarbamate and 8‐hydroxyquinoline but not EDTA inhibited the oxidase. The partially purified enzyme reduced benzoquinone and oxidized the reduced form of nicotinamide‐dinucleotide (NADH). Ubiquinone, a benzoquinone derivative, but not menadione or vitamin K1, naphthoquinone derivatives, could replace benzoquinone in the oxidation of NADH. Ubiquinone, benzoquinone and similar p‐quinones may function in the orange as the oxidation‐reduction couple between NADH‐quinone reductase and diphenol oxidase.
A METHOD FOR ESTIMATING THE FUNCTIONAL CAPILLARY SYSTEM IN SKELETAL MUSCLE
Authors: DALRYMPLE R. , CASSENS R. G. , BRISKEY E. J.
Published: August 2006

SUMMARY: The functional capillary system was investigated by injecting trypan blue dye into 8 market‐weight porcine animals followed by extracting the dye from various muscles. The trapezius contained more dye than the biceps femoris, with the gluteus medius and longissimus dorsi being equal in dye content but containing less dye than the trapezius and biceps femoris muscles. This rank compared well with the fiber type distribution, with the trapezius being high in red fiber content. The method presents possibilities for study of capillary function but some problems were encountered with the injection procedure.
POST‐MORTEM ISOMETRIC TENSION CHANGES AND SHORTENING IN TURKEY MUSCLE STRIPS HELD AT VARIOUS TEMPERATURES
Authors: JUNGK R. A. , MARION W. W.
Published: August 2006

SUMMARY: A study of the physical changes associated with rigor mortis in breast muscle was undertaken to assess the factors that may influence ultimate tenderness. Isometric tension changes and shortening were measured at temperatures 2–37°C. These changes were measured while holding the muscle strips in a phosphate buffer, pH 7.2. Isometric tension was measured by transducers and recorded on a physiograph. A pattern of tension development and gradual relaxation has been demonstrated to occur post‐mortem in strips of turkey breast muscle held isometrically. The time to maximum tension development occurs in 3.85 ± 0.19 hr and is not linearly related (P <.05) to temperature. The amount of maximum tension developed averaged 25 g/cm2 and was significantly (P < .05) related to temperature. Relaxation to about 50% of maximum occurs in 18 hr. The amount of shortening that occurs post‐mortem is linearly related (P < .01) to temperature. No “cold shortening” of turkey breast muscle was evident.
COMPARATIVE GROWTH OF CLOSTRIDIUM PERFRINGENS IN CARBON DIOXIDE AND NITROGEN ATMOSPHERES
Authors: PAREKH KANTILAL G. , SOLBERG MYRON
Published: August 2006

SUMMARY: Relative growth rates of 8 food poisoning strains of Clostridium perfringens in 100% nitrogen atmosphere and in a 100% carbon dioxide atmosphere at 760‐mm pressure were determined. Growth was measured by the pour plate method. Substrate was fluid thioglycollate medium flushed with 100% nitrogen gas or 100% carbon dioxide gas at atmospheric pressure and incubation was at 43° C Headspace gas in the culture flask was analyzed during the growth period. The nitrogen was reduced at the end of 5 hr but the carbon dioxide remained at approximately 100% during the 3.5‐4‐hr exponential growth phase. Generation time of the Clostridium perfringens strains grown in 100% nitrogen atmosphere varied from 12.9–16.9 min and in the 100% carbon dioxide atmosphere from 12.9–17.2 min. When comparing individual strains in carbon dioxide versus nitrogen, no significant difference was noticed. When each of the 8 strains was compared with one another in a nitrogen atmosphere, as well as in a carbon dioxide atmosphere, significant differences were noticed in growth rates.
VARIATIONS OF RELATIVE RETENTION TIMES IN OPEN‐TUBULAR GAS‐CHROMATOGRAPHIC COLUMNS: RELEVANCY TO FRUIT VOLATILES
Authors: SCHULTZ T. H. , MON T. R. , FORREY R. R.
Published: August 2006

SUMMARY: Open‐tubular gas chromatographic columns made from stainless steel tubing, coated with methyl silicone oil, give variable retention times for individual alcohols, dependent on the size of sample. This difficulty is largely overcome by using a small proportion of adsorption‐reducing material with the methyl silicone. There are cases of reversal of peak order, caused by differences in column temperature or minor differences in the coating. However, with care, relative retention times are nearly constant and are helpful as an aid in identification of compounds. A procedure for precise comparison of the retention times of unknown fruit volatiles with known compounds is described. Relative retention times of representative compounds are given for twelve different stationary liquids.
EFFECT IN RATS OF PARTIAL REPLACEMENT OF COW'S MILK PROTEIN BY SUPPLEMENTARY NITROGEN
Authors: YOUNG VERNON R. , VILLARREAL ABEL
Published: August 2006

SUMMARY: A number of experiments studied growth of weanling rats and urinary nitrogen excretion in young adult rats when cow's milk protein was partially replaced by varying levels supplementary nitrogen. A mixture of nonessential L‐amino acids (NEAA) or a mixture of diammoniumcitrate and glycine (DAC‐Gly) was used as the source of nitrogen. Substitution of the 15% milk protein diet to the extent of 10% slightly reduced growth; significant growth reduction occurred with substitutions of 20% and greater. Fortification of the diets containing 10.5% milk protein and the supplementary nitrogen sources with sulfur amino acids did not restore growth the maximum rate obtained with the 15% milk protein diet. Additional supplementation with tryptophan further improved growth slightly but not to the maximum rate. Several other essential amino acids, alone or in combination, had no apparent effect. Based on urinary nitrogen excretion, comparable results were obtained with young adult rats by substituting nitrogen for milk protein the diets. The reduced performance following substitution of milk protein with supplementary nitrogen may be due partly to decreased utilization of sulfur amino acids and possibly to decreased utilization of all essential amino acids.
LOW‐TEMPERATURE, LONG‐TIME HEATING OF BOVINE MUSCLE 2. Changes in Electrophoretic Patterns
Authors: LAAKKONEN E. , SHERBON J. W. , WELLINGTON G. H.
Published: August 2006

SUMMARY: Polyacrylamide gel electrophoresis was used to follow changes in the nature of the water‐soluble proteins and juices of bovine muscle during low‐temperature heating. The slowestmoving anodic proteins were coagulated first. The myoglobins and myoalbumins were altered significantly only by holding the meat at 60°C. The largest changes in tenderness and amount of water‐soluble material in the meat occurred at the same temperatures under which the slow‐moving proteins were denatured. The most heat‐sensitive proteins detected were denatured before there were significant changes in tenderness or water‐soluble substance content.
POULTRY PRODUCT QUALITY. 3. Organoleptic Evaluation of Cooked Chicken and Turkey Skin Fractions as Affected by Storage Time and Temperature
Authors: MacNEIL J. H. , DIMICK P. S.
Published: August 2006

SUMMARY: Cooked turkey and chicken skin residue and separated drippings or oil were stored at various temperatures then presented to a trained taste panel for flavor evaluation. Panel members were able to discriminate between a control (unstored) and a sample of residue after 3 wk of storage at 40°F. They were not able to differentiate between control and treatment (stored) oil even after 7 wk of storage. When chicken skin residue and oil were evaluated after storage at 40°F the panel members could detect differences between the residue samples at 3 wk, but unlike the turkey oil stored at the same temperature they indicated discriminatory ability after 1 wk of storage. When both cooked chicken and turkey skin fractions were presented to the panel at the same time without a reference control (unstored) they were able to identify differences but could not indicate a clear preference for either one.
Role of Cuticle in Spoilage of Chicken Eggs
Authors: VADEHRA D. V. , BAKER R. C. , NAYLOR H. B.
Published: August 2006

SUMMARY: The role of cuticle (mucoprotein layer on the egg shell) in preventing spoilage of eggs by microorganisms was studied. Eggs collected from the uterus or eggs treated with 5% EDTA solution to remove cuticle spoiled at a much faster rate than the normally laid eggs. The weight of the egg shell and its membranes did not affect the spoilage of eggs collected from the uterus. The protection provided by the cuticle was found to last at least up to 96 hr after the eggs are laid.
Respiration of Potato Mitochondria and Whole Tubers and Relation to Sugar Accumulation
Authors: PAEZ L. E. , HULTIN H. O.
Published: August 2006

SUMMARY: We have made a quantitative assessment of the changes in reducing and non‐reducing sugar contents and respiration in stored White Rose potato tubers as a function of temperature of storage. The increase in sugar content with decrease in storage temperature and the decrease in sugars with increase in temperature is accounted for in only a minor way by the corresponding decrease or increase in respiratory’activity of the tubers. The maximal possible contribution of respiratory activity to the changes in sugar content varied from less than 1% to 13% depending on the particular storage conditions. The temperature‐dependence of respiratory activity of potato mitochondria was compared to that of whole tubers, and a quantitative comparison was made of the potential respiratory activity of the mitochondria to respiration of the whole tubers. The potential mitochondrial activity is such that respiration of whole tubers would not be limited by this factor at any temperature studied although it is recognized that the effect of mitochondrial activity could be an indirect one. Unlike whole tubers, mitochondria displayed a temperature response typical of an enzymic reaction with an apparent energy of activation of 14,000 cal/mole with succinate as substrate. The temperature‐dependence of potato mitochondrial respiration is typical of that found for other plant mitochondrial systems but differs markedly from that of mitochondria of mammals and poikilotherms.
Sodium Chloride Effect on Autoxidation of the Lard Component of a Gel
Authors: ELLIS R. , GADDIS A. M. , CURRIE G. T. , THORNTON F. E.
Published: August 2006

SUMMARY: Stable gels composed of lard, sodium carbomethoxy cellulose and water were used for the examination of factors involved in the pro‐ and antioxidant activities of sodium chloride, other inorganic salts, heme compounds, meat fractions and other additives. Autoxidation processes were evaluated by peroxide and monocarbonyl determinations. The solid translucent gels, in which additives had been incorporated, were stored frozen, freeze‐dried or allowed to oxidize without physical change. The hydrated gels were well aerated in preparation and oxidized in the dark at a convenient pace at 20°C. When the gel was freeze‐dried, a sponge‐like structure was obtained which, after an induction period, autoxidized rapidly. Freezer‐stored gels autoxidized at a rate roughly similar to freezer‐stored meat. Sodium chloride had a direct pro‐oxidant action on the lard of freezer‐stored and dehydrated gels. Hydrated gels containing NaCl when stored at 20°C had an inhibiting autoxidation pattern somewhat similar to the quantitative influence of NaCl on pH. Ethylene‐diaminetetraacetate (EDJA) had a powerful antioxidant influence. Sodium chloride accelerated heme catalysis regardless of the presence of antioxidant or chelator. Interesting differences in monocarbonyl patterns and monocarbonyl/peroxide ratios as influenced by additives and moisture content of the gels were observed.
Factors Affecting the Distribution of Lactate Dehydrogenase Between Particulate and Soluble Phases of Homogenized Trout Skeletal Muscle
Authors: MELNICK RONALD L. , HULTIN H. O.
Published: August 2006

SUMMARY: Skeletal muscle of brown trout contained one electrophoretically distinguishable lactate dehydrogenase (LDH) isozyme. In homogenates of the muscle, release of the enzyme into the soluble phase was favored by high ionic strength and high pH. DPNH solubilized the enzyme and prevented binding of soluble enzyme to particulate matter at concentrations which contributed only negligibly to the ionic strength of the suspending medium. The other compounds involved in the LDH‐catalyzed reaction, DPN+, pyruvate, and lactate, were less effective. The effect of the latter two was due chiefly to their contribution to the ionic strength of the medium. Pyruvate, however, used with either DPNH or DPN+ exhibited a synergistic activity. Effective solubilization showed remarkable specificity for DPNH and TPNH. Solubilization by DPNH was also dependent on the tissue concentration of the suspending medium. The lower the tissue concentration, the more readily LDH is solubilized by DPNH. In addition to certain metabolic implications, this information may be used to define assay conditions to allow the study of the kinetics of LDH in bound and soluble forms.
Physicochemical Nature of Banana Pseudostem Starch
Authors: SHANTHA H. S. , SIDDAPPA G. S.
Published: August 2006

SUMMARY: Starch was isolated from banana pseudostem and its properties were compared with those of potato, corn and tapioca. The starch granules are irregular in shape and are bigger in size than those of the fruit starch. At 60°C, the granules start to swell, gradually increase in size, attain their maximum size at 75°C and do not rupture even after heating to 100°C. The intrinsic viscosity of the starch (2.05) is similar to that of potato starch (2.00). The amylose content of the starch compares well with that of banana fruit and potato (tuber) starch (21%). In general, banana pseudostem starch resembles potato starch.
Resistance of Clostridium perfringens to Varying Degrees of Acidity during Growth and Sporulation
Authors: FISCHER LINDA H. , STRONG DOROTHY H. , DUNCAN CHARLES L.
Published: August 2006

SUMMARY: Viable cells of each of 6 strains of Clostridium perfringens were exposed to 4 levels of acidity during phases of the growth cycle. The selected strains included 4 which had been recovered in association with food poisoning outbreaks and 2 strains not so associated. The growth media tested included Fluid Thioglycollate Medium, DS‐sporulation medium and the CP‐2V medium proposed by Hauschild.

The level of acidity, length of exposure of the cells, the growth medium employed and the phase in the growth curve influenced the survival of C. perfringens. Exposure of cells grown in DS‐sporulation medium to buffers pH 6.0 had little effect on the survival over the 8‐hr test period, with somewhat greater sensitivity of cells being demonstrated at pH 4.5. Exposure of cells, similarly produced, to buffer pH 1.0 or 2.0 was much more effective in reducing the percentage of survival, particularly during early log phase and at the onset of sporulation. Based on the 3 growth media utilized, calculated survival curves resulting from exposure of cells to pH 1.0 or 2.0 were erratic in shape, and percentage survival was almost universally less than 10%.

Source of the strain, whether food poisoning or non‐food poisoning associated, appeared to have no significant effect on the acid resistance of the cells. The comparatively regular increase in the percentage of survivors after the initiation of sporulation suggests that spores exhibit a greater resistance to acid stress than vegetative cells.

Incubation at temperatures of 37° or O°C, during the time of treatment with the test buffers pH 1.0 or 2.0, produced no consistent change in the percentage of survivors when the cells were grown in FTG.
AN EXPERIMENTAL STUDY OF MOISTURE AND TEMPERATURE DISTRIBUTIONS DURING FREEZE‐DRYING
Authors: HATCHER JOHN D. , LYONS DONALD W. , SUNDERLAND J. EDWARD
Published: August 2006

SUMMARY– Measurements of the moisture and temperature distributions were made during freeze‐drying beef at a pressure of 1 torr. The transient moisture distributions measured with gamma ray techniques indicate that the phase change region would have a thickness less than 3/16 in., that no drying takes place until the phase change region reaches a given position, and that no additional drying occurs after the phase change passes a given position. A careful study of the data showed that the drying rate was influenced by heat transfer through the frozen region to the phase change position.
STABILIZATION OF CARROT JUICE BY DILUTE ACID TREATMENT
Authors: STEPHENS THOMAS S. , SALDANA GUADALUPE , BROWN HAROLD E. , GRIFFITHS FRANCIS P.
Published: August 2006

SUMMARY– A problem arises if juice extracted from raw carrots is heated to about 180° before or during conventional canning practices. An unsightly, unappetizing coagulum forms and the color of the juice precipitates with the coagulum. The coagulum is not as evident if the carrots are heated 5 min in water prior to juice extraction, but the juice loses some of its bright‐orange color. The canned juice extracted from carrots heated 5 min in a .05 N acetic acid solution does not coagulate and the amount of juice which can be extracted from the carrots is 3.3% greater than that from carrots heated 5 min in water. The centrifuged juice from acid‐treated carrots had a brighter orange color than juice from the water‐treated carrots. The color notation was Rd, 23.7, a, 30.4 and b, 34.8 for juice from acid‐treated carrots compared with a notation of Rd, 19.2, a, 24.4 and b, 31.4 for the juice from water‐treated carrots. The canned juice extracted from raw carrots had less pectic substances and starch and about the same amount of protein as the canned juice from the carrots heated in water or .05 N acetic acid, but the canned juice from raw carrots coagulated. The juice from carrots heated in acid does not form a coagulum and maintains its orange color, probably because of the action of the heat and acid on the protoplasmic liquid of the cell before or immediately after the cell is ruptured.