bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on Enzymic Activity of Rat Liver Subcellular Fractions
Authors: SHIBKO S. , TAPPEL A. L. , SUSZ J. P. , FREEDLAND R. A.
Published: August 2006

SUMMARY: Mitochondrial and lysosomal preparations from rat livers were examined for the presence of a number of particulate bound enzymes, previously described as being present in mitochondria. The study sought to determine whether these enzymes were truly mitochondrial or partly associated with lysosomes which are contaminants of most mitochondrial preparations. The amino transferases were of particular interest because of their possible involvement in the metabolism of amino acids which are concentrated within lysosomes. It was shown that particulate aspartate amino transferase and alanine amino transferase are truly mitochondrial enzymes. Particulate glutathione reductase was shown to be distributed between lysosomes and mitochondria, the specific activities in the two particles being almost equal. Possible activation of catheptic protein hydrolysis is discussed. Lysosomes were shown not to contain the following enzymes: isocitrate dehydrogenase, glycerol‐3‐phosphate dehydrogenase, serine dehydratase, glucose‐dphosphate dehydrogenase, xanthine oxidase, aldehyde oxidase and fumarate hydratase. Lysosomes were unable to incorporate amino acids into proteins but were able to incorporate acetate 14C into fatty acids. The importance of this process as a possible mechanism for controlling or altering the structure of the lysosomal membrane is discussed. Relationships of these findings to some properties of meats are discussed.
Changes in Hydrogen Sulfide and Sulfhydryl Content of Heated Beef Adipose Tissue
Authors: PEPPER F. H. , PEARSON A. M.
Published: August 2006

SUMMARY— Beef adipose tissue was separated into the water soluble, salt soluble and insoluble (water‐salt‐ether) fractions, and the amount of H, S evolved upon heating each of the fractions was determined. The yield of H, S per 100 g of adipose tissue was 17.6, 1.7 and 5.5 μM for the water soluble, salt soluble and insoluble fractions, respectively. Thus, the water soluble fraction contributed about 71% of the H, S, while the corresponding contributions from the salt soluble and the insoluble fractions amounted to approximately 7 and 22%, respectively.
Studies in Meat Tenderness. 7. Changes in the Fine Structure of Meat During Aging
Authors: DAVEY C. L. , GILBERT K. V.
Published: August 2006

SUMMARY— During the aging of fiber pieces prepared from bovine sternomandibularis muscles, a loss of adhesion occurs between adjacent myofibrils. This is evidenced by increased readiness of fiber pieces to distintegrate into individual myofibrils during a period of standard disruption. Alterations also appear within the myofibrils themselves in the regions of the Z lines, sometimes leading to the apparent dissolution of this structure. Ethylenediamine tetraacetate present in the suspensions during storage not only prevents these changes, but also preserves the refractory character of the fiber pieces. Meat aging is considered therefore to be due to disruption and possible dissolution of Z‐line material, leading to a weakening of inter‐myofibrillar linkages probably located at the junctions of adjacent Z lines, and to loss of tensile strength of the myofibrils themselves.
Low Temperature Growth of Type E Clostridium botulinum Spores. 1. Effects of Sodium Chloride, Sodium Nitrite and pH
Authors: EMODI A.S. , LECHOWICH R.V.
Published: August 2006

SUMMARY— The effects of pH and the addition of sodium chloride (NaCl) or sodium nitrite (NaNO2) to trypticase‐peptone‐glucose (TPGI and trypticase‐peptone‐sucrose‐yeast extract (TPSY) media upon spore outgrowth were investigated using seven Type E Clostridium botulinum strains. An inoculum of 1.0 × 105 spores/ml was used and the pH was adjusted with hydrochloric acid to cover the range of 5.2 to 6.6. To define salt tolerance, NaCl was added to the media at intervals of 0.5% in the range of 2.0 to 5.0% and at 0.1% intervals in the 4.5 to 5.0% range. The effect of NaNO2 was investigated with the addition of 100 and 200 ppm NaNO2 to the media. Samples were incubated at 30, 15.6, 10, 7.2, 5.0 and 3.4°C. Outgrowth of all strains tested was inhibited at pH 5.2 at 15.6°C. Inhibition occurred at higher pH at lower temperatures. None of the strains showed outgrowth with 4.87% NaCl in the media at any of the incubation temperatures used. Addition of 100 and 200 ppm NaNO2 to the media inhibited the outgrowth of the Minneapolis, 517, 26080 and A6247 strains but not the Kalamazoo and Seattle Forks strains.
VISCOSITY AS AFFECTED BY VARIOUS CONSTITUENTS OF TOMATO JUICE
Authors: FODA Y. H. , McCOLLUM J. P.
Published: August 2006

SUMMARY— Degradation of proteins of tomato juice with pronase caused a relatively small loss of viscosity. Commercial cellulase freed of pectolytic activity with 8 M urea greatly decreased the viscosity of washed tomato solids. Further degradation with pectinase was ineffective in reducing viscosity. Cellulase extracted from the tomato lowered viscosity of tomato juice. Enzymatic degradation as indicated by chemical analysis did not always result in a loss of viscosity. By extracting the solids with water, viscosity of tomato juice was lowered drastically. The extent of the reduction was not affected by previous treatment with cellulase or pectinase. Viscosity was not affected by extraction with versene. The greater reduction in viscosity of tomato juice by extraction of the solids with water than with ethanol indicates that the high molecular polymers associated with the insoluble solids contribute greatly to viscosity. The data did not indicate a significant contribution of the uronides to the viscosity of tomato juice.
EFFECT OF HEATING METHODS ON THIAMINE RETENTION IN FRESH OR FROZEN PREPARED FOODS
Authors: KAHN LESLIE N. , LIVINGSTON G. E.
Published: August 2006

SUMMARY— Thiamine retentions were determined in beef stew, chicken a la f or newburg and peas in cream sauce, which ware 11 freshly prepared and held for 1, 2 or 3 he ld 180°F (82.2°) or 2) freshly prepared, frozen at −10°F (−23.3°C) and reheated to reheated using microwaves, infrared heating or boiling water immersion. Similar treatments had the on the thiamine retention in the various products. The average thiamine retentions Boy de n products (based on 100% for the freshly prepared foods) were 93.5% in the frozen‐microwave heated products; 90% in the frozen‐infrared heated products; 86% in the frozen‐immersion hot products versus 78% in the fresh hot products after 1 hr, 74% after 2 hr and 67% after 3 hr.
MICROFLORA OF FRESH PORK SAUSAGE CASINGS. 1. Regenerated Collagen Casings
Authors: RIHA WILLIAM E. , SOLBERG MYRON
Published: August 2006

SUMMARY— Regenerated collagen casings had contamination levels varying from less than 50 up to 32,000 microorganisms per gram. Greatest recoveries of microorganisms were obtained on the less inhibitory media. Aerobic recovery on Tryptone Glucose Extract Agar was slightly higher than anaerobic recovery on Brewer's Anaerobic Agar. Anaerobic recovery on differential media was similar to aerobic recovery. 61 isolates were obtained from casings by enrichment techniques followed by streak plating. Of these isolates, 57.3% were of the genus Bacillus, 8.2% Pseudomonas, 6.6% Clostridium, 6.6% Streptococcus, 6.6% Lactobacillus, 3.3% Micrococcus, 3.3% Corynebacterium, 1.6% Staphylococcus, 1.6% Escherichia and 1.6% Propionibacterium
RADIATION PASTEURIZATION OF FRESH AND BLANCHED TROPICAL SHRIMPS
Authors: KUMTA U. S. , MAVINKURVE S. S. , GORE M. S. , SAWANT P. L. , GANGAL S. V. , SREENIVASAN A.
Published: August 2006

SUMMARY— The storage life of fresh, peeled and deveined tropical shrimps at 10—12°C is extended to 10—14 and 18—21 days with 0.15 and 0.25 Mrad, respectively, as against spoilage of unirradiated samples within 4 days. Blanching treatment (steaming for 4 min) with or without brine (3.0% NaCl) extends the storage life up to 30 days at lo—12°C. the former retaining the shell‐fish flavor. However, the blanched products develop musty odor and slimy texture during storage; subjected to irradiation (0.15 Mrad) these are devoid of undesirable attributes and are acceptable for 60 and 130 days, respectively, at 10—1°C and 2—4°C. Bacterial counts exceeding 108/g and high levels of TMAN and TVBN concur with spoilage of unirradiated shrimps. In contrast, low levels of TMAN and TVBN, despite high TBC, corroborate with high acceptability of radiation processed shrimps. In blanched as well as in blanched and irradiated shrimps TBC, TMAN and TVBN are low. Samples subjected to blanching only have low acceptability as against the improvement in quality by irradiation. These alterations in storage property have been discussed in the light of shifts in microflora.
REMOVING MICROORGANISMS IN FRESH APPLE JUICE BY BACTERIAL CENTRIFUGATION
Authors: KOSIKOWSKI F. V. , MORENO V.
Published: August 2006

SUMMARY— Bactofugation, a continuous centrifugal process of removing microorganisms from liquid foods, was applied at 9.000 g force to chilled and heated apple juice at a rate of 1,600gph. A reduction 99.8% in total bacterial count and 99.9% yeast‐mold count of fresh apple juice processed at 7° was obtained. Bactofugating chilled apple juice was more effective than bactofugating apple juice heated to 54°C and presented certain operational advantages. Bactofugated, chilled apple juice retained the same flavor as untreated, fresh apple juice and remained fresh 22 days at 5°C, compared to about 5 days for the untreated apple juice. The simplicity of bactofugation, its relatively high put‐through capacity and its effective reduction of microbial populations in fresh apple juice suggest that the process has potential application toward improving the keeping quality of this food.
VELOCITIES OF FALLING FILMS OF WATER ON TEFLON®, GLASS AND STAINLESS STEEL SURFACES
Authors: PATEL SAVINAY , JORDAN W. K.
Published: August 2006

SUMMARY— The velocities of falling films of water on a stainless steel plate (8 by 1.5 ft) with No. 4 surface finish were measured by the salt conductivity method for flows varying from 50 to 250 Ib/min. The downflow times between 2 fixed electrodes, 6 feet apart on the plate, were measured by a Solu‐Bridge flow timer. The film velocity measurements were made with the plate vertical and inclined 30 degrees from vertical, with water at 70 and 140°F. Another setup with a smaller plate (4 by 1.5 ft) and a constant flow of 45 lb/min was used to study the characteristics of falling films of water on Teflon, glass and stainless steel surfaces. The plates could be positioned at any positive or negative angle. The effects on wave structures were recorded photographically. The results showed highest velocities when the plates were vertical. Velocities increased with flow rate and temperature. At a given slope, film velocities were higher for the flow clinging to the underside of the surface than for the flow down the upper side of the surface.
PROCESS FOR OBTAINING STARCH FROM SELECTED GRAIN SORGHUM FRACTIONS
Authors: PEEPLES M. L. , MARSHALL J. T.
Published: August 2006

SUMMARY— A wet process is described for separating selected grain sorghum fractions into a prime and coarse starch fraction. Ammonium hydroxide solutions are used to slurry the sorghum fractions. The slurries are centrifuged and the resulting starch layers are mechanically separated. This process quickly separates the starch from dry‐milled by‐products of grain sorghum.
EFFECT OF FOOD‐PROCESSING METHODS UPON SURVIVAL OF THE TREMATODE HETEROPHYES SP. IN FLESH OF MULLET CAUGHT FROM BRACKISH EGYPTIAN WATERS
Authors: HAMED M. G. E. , ELIAS A. N.
Published: August 2006

SUMMARY— Mullet caught from brackish‐water lakes such as Manzala Lake in Egypt were found to serve as an intermediate host for Heterophyes parasite. Infection of man with this parasite may be very heavy. causing severe symptoms. This study revealed that some food‐processing methods or treatments may not be adequate to kill the parasite in the fish muscle tissues. It was found that Heterophyes could survive for 30 hr when infected fish were stored at −10 or −20°C. Viability was greater, i.e., 9 days, when stored et refrigerator temperature of 6°C. On the other hand, when fish were dipped in chlortetracycline solution (30 pbm) for 2 hr, the parasite's viability was not affected. Moreover, ice treated with oxytetracycline used for fresh fish preservation had no marked influence on the viability of Heterophyes When infected fish were grilled in a manner quite similar to that adopted by Egyptian fisherman during their fishing trips, about 20‐30% of the fish contained living metacercariee of Heterophyes owing to the insufficiency of the heat treatment. Further, in mullet kept at 50 and 100°C, the parasite lived for 180 and 10min. respectively. Thus, insufficient processing or treatment of brackish‐water mullet does not completely destroy the parasite, thereby rendering such fish hazardous to the health of persons consuming them.
AFLATOXIN PRODUCTION AS AFFECTED BY ENVIRONMENTAL CONDITIONS
Authors: EPSTEIN EDWARD , STEINBERG M. P. , NELSON A. I. , WEI L. S.
Published: August 2006

SUMMARY— The effects of controlled atmosphere (CA) (10% CO2, 1.8% O2 and 88.2% N2 and air were noted on the growth of aflatoxin production of Aspergillus flavus incubated at several temperatures on 2 substrates. In liquid medium, the mold grew well and produced toxin in both air and CA at room temperature. At 60°F, growth and toxin were substantial in air but minimal in CA. At temperatures of 54°F and below. toxin was inhibited; growth was minimal in air and inhibited in CA. Cracked corn of 16.6, 18.8, 23.6 and 31.2% moisture content (dry basis) also was studied. At 31.2% moisture and 60°F, growth was reduced in CA to a greater extent than in air. whereas sporulation and toxin in CA showed a longer lag period at both 84 and 60°F.
TRACE HYDROGENATION OF BUTTEROIL AT LOW TEMPERATURES
Authors: VASISHTHA A. K. , LEEDER J. G. , CHANG S.S.
Published: August 2006

SUMMARY— The present investigation describes a process of selective trace hydrogenation of butteroil at low temperatures using palladium catalyst. Butteroil was selectively trace hydrogenated at low temperatures, in some instances in a semisolid state. The hydrogenated product had a remarkable flavor stability and without appreciable increase in trans‐isomers and melting point. The hydrogenated butteroil also retained most of its desirable flavor and color.
FLAVOR MODIFICATIONS PRODUCED IN ICE CREAM MIX MADE WITH CORN SYRUP. 2. CO2 Production Associated with the Browning Reaction
Authors: EOPECHIMO A. A. , LEEDER J. G.
Published: August 2006

SUMMARY— Low and high‐conversion corn syrups were used to partially replace the sucrose in ice cream mix subsequently heated at various times and temperatures. The effect this practice had on the browning reaction was recorded by the amount of CO2 evolved during heating. A well‐known inhibitor of the browning reaction was added to some mixes before processing. Results indicated that the variables tested significantly influenced the extent of the browning reaction in heated mix. These factors, moreover, exhibited considerable interplay, as shown by the predominance of statistically significant 2‐ and 3‐factor interactions. Corn syrup containing the greatest concentration of reducing sugars was most active in promoting the browning reaction in ice cream mix. The effect of changing any of the variables on the reaction was most marked in mix made with this syrup. Potassium metabisulfite displayed the general effect of lowering the degree of the browning reaction.
PRESSURE RELATIONSHIPS IN THE REGENERATOR OF AN EGG PASTEURIZER
Authors: SCALZO A. M. , DICKERSON R. W. , READ R. B.
Published: August 2006

–In current egg pasteurization practice, the pressure of raw egg is greater than that of pasteurized egg in the regenerator. Any leakage could contaminate the processed egg. To solve this problem, a commercial pasteurizer was operated with the metering pump located between the regenerator and heater sections and a centrifugal booster pomp employed to prevent cavitation in the regenerator. The method was successful. The pasteurized egg was under a greater pressure than the raw egg in the regenerator for the 4 products studied.
CITRUS PRODUCT COLOR ENHANCEMENT USING EXTRACTS OF PEEL OF DIFFERENT VARIETIES
Authors: KEW THEODORE J. , BERRY ROBERT E.
Published: August 2006

SUMMARY— Colored fractions ware extracted and concentrated from peel of most commercial orange varieties and used to enhance the color of orange juice products. These included Pineapple, Hamlin, Parson Brown, Valencia, blood orange and Dancy tangerine. The relative yields of crude pigment per kg of peel were compared between he different varieties. The color extracts were analyzed for tristimulus yellowness (Y) and redness (RI factors. Crude pigment yields ranged from .34 g (Hamlin) to 1.29 g (Dancy tangerine) per kg of peel. R factors were highest for Dancy tangerine, followed by Pineapple orange and Valencia, and lowest for Hamlin. Y factors were highest for Dancy tangerine, followed by Valencia and Pineapple and lowest for Hamlin. Most color extracts were effective at a dilution of 113500 parts in improving the color of orange juice products.
CHEMICAL AND PHYSICAL CHANGES IN IRRADIATED AND FROZEN BOMBAY DUCK
Authors: KUWTA U. S. , GORE M. S.
Published: August 2006

SUMMARY— Bombay duck (Harpodon nehereus), a tropical fish, is readily susceptible to drip losses leading to textural alterations. These changes occur during storage at 0 or −20°C for 3 days and also by irradiation and storage at 0 or 10°C for 3 days. In situ denaturation of fibrillar proteins of Bombay duck occurs as evidenced by a decrease in salt‐soluble proteins. Loss in extractability occurring at 0 or −20°C parallels increased drip loss, but appears to be arrested by pre‐dip treatment in 10% sodium tripolyphosphate solution for 15 min. The radiation‐induced drip loss also correlates with loss in the extractability at a radiation dose of 3 Mrad, but at 0.5 Mrad the drip loss occurs without appreciable decrease in the extractability. Pre‐dip treatment in 10% sodium tripolyphosphate solution reduces the drip loss caused by 3 Mrad, but this is not reflected in the recovery of extractable proteins. Loss in the extractability could be attributed to the aggregation phenomenon of fibrillar proteins induced by irradiation. The radiation‐induced off‐odors appear to originate from the sarcoplasmic proteins.
FAT DETERMINATION‐A NEW PHYSICAL METHOD
Authors: BITTENBENDER C. D.
Published: August 2006

SUMMARY— A fat determination method based on precise hydrometric measurement of the relative density of a solution of the fat contained in a sample dissolved in a constant volume of heptane is presented. The apparatus and method are described in detail and comparative results by this method and by the A.O.A.C. method am presented. The effect of various factors on results is established. The application of another solvent, less hazardous than heptane. is also described.
SOME PROPERTIES OF MYOFIBRILLAR PROTEINS OBTAINED FROM LOW IONIC STRENGTH EXTRACTS OF WASHED MYOFIBRILS FROM PRE‐ AND POST‐RIGOR CHICKEN PECTORAL MUSCLE
Authors: FUKAZAWA TOSHIYUKI , NAKAI HIROYASU , OHKI SHIRO , YASUI TSUTOMU
Published: August 2006

SUMMARY— Changes in extractability of the proteins associated with the fragmentation phenomenon of myofibrils in chicken pectoral muscle were studied. The results indicate that the protein fractions extracted by neutralized water from muscle residue. from which water‐soluble proteins have been washed out, increase in post‐rigor muscle. The extracts from pre‐ and post‐rigor muscle were fractionated with ammonium sulfate into two fractions: the fraction precipitated by 1.7 M ammonium sulfate (Fr.1) and the supernatant (Fr. 2). Depressing effect on the onset of ATP‐induced superprecipitation of trypsin‐treated myosin 6 which was initially present in Fr. 2 from pre‐rigor muscle decreased to a great extent in that from post‐rigor muscle, whereas promotive effect on gelation of F‐actin and superprecipitation of the myosin 6 which was little in Fr. 1 from pre‐rigor muscle appeared in that from post‐rigor muscle. It is proposed that an increasing amount of protein which indicates α‐actinin activity is released along with the destruction and final dissolution of the Z‐line structure during postmortem storage of chicken pectoral muscle.
QUALITATIVE AND QUANTITATIVE CHANGES IN AEROBIC MICROFLORA FROM INTESTINAL CONTENTS OF SOUTH‐BALTIC COD DURING STORAGE AT 1‐2°C
Authors: GARCIA‐TELLO PATRICIO , ZALESKI STANISLAW
Published: August 2006

SUMMARY— The bacterial flora of the intestinal content of cod (Gedus morrhua L) were investigated during a period of 1 year. The quantity of bacteria in recently caught fish was studied during the full period. the quality during only 6 months. 3 groups of fish from the same capture and fishing grounds were analyzed: fresh, and stored at 1–2°C for 5 and 10 days. It was seen that in general gram‐positive bacterial flora dominated in recently caught fish, while after 5 and 10 days of storage gram‐negative flora our numbered the former. In the intestinal contents of fresh fish the Vibrio species dominated, whereas at storage, Pseudomonas spp. became dominant. In fresh fish, the bacterial flora of stored fish amounted to 3.10% of the total initial quantity after 5 days of storage and 1.5% after 10 days. Also, the gram‐positive flora decreased comparatively more rapidly than gram‐negative flora. The authors believe that the temperature of 1–27°C may play a part in the decreasing number of flora, as well as some other factors not investigated in the present research.
HISTOLOGICAL METHODS FOR STUDYING CONNECTIVE TISSUE IN THE LONGISSIMUS DORSI MUSCLE IN PORK
Authors: DEETHARDT DOROTHY , TUMA HAROLD
Published: August 2006

SUMMARY— 3 fixatives [10% formalin (1), F.A.A. (II) and 10% formalin and saline (III)] used for the histological study of collagen. reticular and elastic fibers in the connective tissue of pork longissimus dorsi muscle did not significantly affect the mechanics of sectioning or mounting the tissue. The type of fixative used war found to affect the quantity of stained connective tissue. The sample fixed in the formalin‐saline fixative (III) yielded a smaller amount of reticular and collagen fibers than the samples fixed in fixatives I and II. A triple staining procedure was used for the 3 connective tissue elements: silver for reticulin, aniline blue for collagen and orcein for elastin. The reticular and collagen fibers stained as well in the cooked as in the raw sample. Little elastin was evident in the longissimus dorsi.
SPECIFICITY OF THE FERRIC‐H2SO4 REAGENT FOR ALGINATES
Authors: GRAHAM HORACE D.
Published: August 2006

SUMMARY— Alginate in foods was isolated from papain digests of the samples as the insoluble calcium salt. dispersed by sodium hexametaphosphate and a 1‐ to 5‐ml aliquot of the dispersion 50–250 μg of sodium alginate) dried at 100°C. Heating of the anhydrous sample in the presence of the ferric‐H2SO4 reagent for 12 min at 60°C produced a pink color with maximum absorption at 490–515 mμ and maximum density after aging for 90 min at 29±1°C. Under these conditions, proteins, amino acids (except tryptophane), other carbohydrates, vitamins. food additives and incipients did not interfere. The presence of water in the medium rendered the reaction nonspecific and increasing the temperature above 60°C or heating for longer periods at lower temperatures resulted in color formation by other polyuronides, especially pectin and pectic acid. Recoveries of alginate from several products were good: Milk, 94–98%; ice cream, 93.5–98%; pasteurized process cheese spread. 92.6‐95%; chocolate milk, 92.4‐95%; dietetic foods, 90‐97.2%.
MOLECULAR PROPERTIES OF POSTMORTEM MUSCLE. 8. Effect of Postmortem Storage on α‐Actinin and the Tropomyosin‐Troponin Complex
Authors: ARAKAWA NOBUHIKO , GOLL DARREL E. , TEMPLE JOANNE
Published: August 2006

SUMMARY– Effects of postmortem storage of rabbit muscle at 25° on the properties of α‐actinin and tropomyosin‐troponin‐containing fractions prepared from this muscle were studied. Postmortem storage did not affect the amount of α‐actinin or tropomyosin‐troponin that could be extracted from rabbit myofibrils by water washes or by a 3‐day, pH 8.5, low‐ionic strength extraction. Myosin B prepared from postmortem muscle underwent turbidity development much faster than myosin B prepared from muscle immediately after death. This increased rate of turbidity development was probably not due to postmortem changes in α‐actinin, since the ability of α‐actinin to accelerate the ATPase (for abbreviations used in this paper, see list under References) activity or the turbidity response of reconstituted actomyosin suspensions gradually decreased, rather than increased, during postmortem storage. However, even after 14 days postmortem at 25°α‐actinin retained some activity in both the ATPase and turbidity tests. Moreover, the increased rate of turbidity development of postmortem myosin B was probably not due to degradation of the tropomyosin‐troponin complex, since postmortem storage affected the activity of this complex only slightly and, even after 14 days post‐mortem, the tropomyosin‐troponin complex still conferred some Ca++‐sensitivity on reconstituted actomyosin suspensions. Myosin B prepared from postmortem muscle did not contain more active α‐actinin than myosin B prepared from muscle immediately after death, but the F‐actin‐tropomyosin‐troponin interaction was gradually weakened during postmortem storage without any evident degradation of F‐actin and the tropomyosin‐troponin complex themselves. The weakened F‐actin‐tropomyosin‐troponin interaction probably caused loss of Ca++‐sensitivity in myosin B prepared from postmortem muscle. Results of this study indicate that postmortem changes in α‐actinin and the tropomyosin‐troponin complex per se are not the primary cause of postmortem modification in the actin‐myosin interaction.
DENATURATION THERMOPROFILES OF SOME PROTEINS
Authors: KARMAS ENDEL , DiMARCO G. ROBERT
Published: August 2006

SUMMARY– Denaturation thermoprofiles of raw beef muscle tissue and egg albumin were determined. Irreversible changes occurred in two stages: the first peak was observed at 65° and 73°C and the second at 82° and 83°C, respectively for beef muscle tissue and egg albumin. Pertinent calculations suggest that the second peak is due to changes in the water structures. It may be hypothesized that protective, semicrystalline water structures surrounding the nonpolar amino acid radicals of proteins were collapsed by heat, followed by the formation of hydrophobic bonding yielding aggregated denatured state. Thermodynamic information was obtained from the thermoprofiles.
THE FLAVOR VOLATILES OF DEHYDRATED CABBAGE
Authors: MacLEOD A. J. , MacLEOD GLESNI
Published: August 2006

SUMMARY– Using previously described sampling techniques, the flavor volatiles of a number of dehydrated cabbage samples were collected and then analyzed by gas chromatography. Quantitative measurements were made of the individual components and results compared with those for fresh cabbage. Many differences were observed, in general indicating the poor nature of the preserved product as a substitute for the fresh vegetable. In particular allyl cyanide (3‐butene nitrite) was much increased in the dehydrated samples, whereas the important allyl isothiocyanate was virtually lost altogether. Keeping qualities of the dehydrated samples were also investigated.
ALCOHOL‐INSOLUBLE CONSTITUENTS OF JUICE VESICLES OF CITRUS FRUIT
Authors: TING S. V.
Published: August 2006

SUMMARY– The texture of the edible portion of citrus fruit is determined by the characteristics of the juice vesicles and their insoluble constituents. Alcohol‐insoluble solids (AIS) of the juice vesicles of several varieties of oranges, grapefruit and tangerines were studied at different stages of maturity. The protein content of the AIS as determined by the Kjeldahl method was found to decrease with fruit maturity, although total amount per fruit tended to increase. Polysaccharides were separated by extracting the AIS with alkali of various concentrations. Each fraction after hydrolysis was analyzed for the monomers both by paper chromatography and gas chromatography of the silylated derivatives. Galactose, arabinose and traces of glucose were found in fractions associated with galacturonic acid, and xylose, arabinose and glucose in different proportions were found in the hemicellulose and cellulose fractions. Traces of rhamnose and other uronic acids also were detected.
COLORIMETRY OF FOODS. 3. Carrot Puree
Authors: HUANG I‐LO , FRANCIS F. J. , CLYDESDALE F. M.
Published: August 2006

SUMMARY– A series of 10 carrot purees was prepared with added FD&C Green No. 1 food color in increments of 0.015 ppm. The samples were evaluated visually for color differences under illumination of 7400°K and measured with a G.E. spectrophotometer with D&H tristimulus integrator and a Hun terlab D25 colorimeter in cells varying from 2–8 mm in thickness against both a white and black background. The instrumental data were calculated in conventional and K/S ratios and correlated with visual and theoretical rankings. The panelists could reasonably well rank samples differing by 0.10–0.15 delta E units, calculated as [(delta L)2+ (delta a)2+ (delta b)2 1/2. Highest correlations with the theoretical order were obtained with a black background and sample thicknesses of 6 mm or more. Adequate rankings with either instrument required a multiple correlation with all 3 color parameters (X Y Z or L a b). Optimum separation of samples with the G.E. spectrophotometer was obtained with a white background and a sample thickness of 5 mm or more. The Hunterlab D25 colorimeter was superior to the G.E. spectrophotometer for separation of samples. Optimum separation was with a 2‐in.‐diameter aperture and a cell 4 mm or more in thickness against a white background. Correlations of Hunter data with theoretical order were higher than those with visual vs. theoretical ranking. Individual K and S values may be useful in characterizing purees for colorimetry.
FEASIBILITY OF ACCELERATED TESTS FOR BROWNING IN DEHYDRATED CABBAGE
Authors: MIZRAHI S. , LABUZA T. P. , KAREL M.
Published: August 2006

SUMMARY– Feasibility of using accelerated tests for deterioration of dehydrated vegetables through nonenzymatic browning was evaluated. Studies were made on unsulfited freeze‐dehydrated cabbage. Two procedures for shortening the time required to predict shelf life were used: (1) Extrapolation from high to low moisture contents; and (2) Extrapolation from high to low temperatures. A combination of the two procedures was also evaluated. It was determined that activation energy for browning was dependent on moisture content, and an equation expressing this dependence was developed. Equations relating rates of browning to moisture content at a given temperature were also obtained. Extrapolations based on either procedure, or on a combination of both, gave satisfactory results. The variance of the extrapolation‐based estimates of browning rates was dependent on the number of points used for the extrapolation. The procedures used reduced the time required to obtain browning‐rate data at low moisture contents from over a year to only 10 days.
THERMAL BROWNING OF TOMATO SOLIDS AS AFFECTED BY CONCENTRATION AND INHIBITORS
Authors: DANZIGER M. T. , STEINBERG M. P. , NELSON A. I.
Published: August 2006

SUMMARY– The amount of brown color developed was always determined by reconstituting the sample to 5.6% total solids and measuring optical density (O.D.) of an acetone extract at 420 mμ. Tomato solids at concentrations of 5.6 to 98% were heated for 15 min at 95°C. The O.D. increased slowly with increasing concentration to about 50% solids. Thereafter, the O.D. increased rapidly to a peak at 95% and decreased to half this value at 98%. The effect of heating time at 55, 75 and 95°C and at 5.6 and 45% solids was studied. The browning rate was slight at the lower 2 temperatures relative to that at 95°C, and was much more rapid at the higher concentration than at single strength. Under each temperature and solids condition, the rate of browning was highest at the earlier times. The inhibition effects of pH and SO2 were studied. Browning was at a minimum at pH 2.5. Browning could be further reduced at each pH by increasing levels of SO2. The protective effect of acidification and SO2 addition increased with increasing solids concentration.
THE HELICAL PUMP: USE AS A MULTIZONE PROCESSING SYSTEM
Authors: ROCKWELL W. C. , FARKAS D. F. , LAZAR M. E.
Published: August 2006

SUMMARY– A hydrostatic processing system consisting of a compression zone, a holding zone, and a decompression zone has been built from a single coil of pipe. Theoretical maximum operating pressure is the product of the number of turns in the compression zone and the diameter of the coil. Problems of air compression and disruptive air expansion, noted in a previous model, have been overcome by an innovative air feedback system. Crosstubes, another innovation, are used to maintain a constant pressure in the holding zone of the coil. Experimental results on a model operating at 9 psig show that hydrostatic pressures in the holding zone under continuous conditions are about 90% of theoretical. Packages moving through the unit were found to have a pressure history similar to conventional hydrostatic processing systems that use single tall vertical legs for compression and decompression.
AN EXPERIMENTAL DRY CAUSTIC PEELER FOR CLING PEACHES AND OTHER FRUITS
Authors: HART M. R. , GRAHAM R. P. , HUXSOLL C.C. , WILLIAMS G.S.
Published: August 2006

SUMMARY– An experimental cling peach peeler was developed for continuous removal of alkaline peel as a solid rather than the dilute slurry of common industrial practice. The peeler consists of rows of soft rubber disks rotated in such a manner that peel material is gently wiped from the surface of fruit and flung into collectors. Cling peach halves were successfully peeled in a number of tests, with peeling losses comparable to those normally obtained commercially. Both mature and immature Bartlett pears were also successfully peeled. Dewaxing of immature pears with isopropy1 alcohol was necessary to obtain adequate peeling. In single tests, whole apricots and freestone peaches were also successfully peeled.
PHYSICAL AND CHEMICAL PROPERTIES OF EPIMYSIAL ACID‐SOLUBLE COLLAGEN FROM MEATS OF VARYING TENDERNESS
Authors: KRUGGEL WILLIAM G. , FIELD RAY A. , MILLER GLENN J.
Published: August 2006

SUMMARY: Components of the molecular structure of epimysial acid‐soluble collagen (ASC) from meats of varying tenderness were studied by several methods. The ASC was studied since it contains an appreciable amount of intramolecular cross‐links but is still soluble. Though the amount of total collagen in epimysial tissue was found to have no correlation with meat tenderness, the molecular studies indicated some correlation of the type of epimysial ASC with meat tenderness. Sucrose density‐gradient ultracentrifugation analyses of denatured epimysial ASC suggested that this type of collagen contains a lesser degree of cross‐links when obtained from tender meat samples. Viscosity measurements were found to be correlated to tenderness of meat in a manner similar to the results obtained by ultracentrifugation, in that the intrinsic viscosity of epimysial ASC from tender meat was lower than that from tough meat, indicating differences among the relative sizes of the collagen molecules from the different samples. Partial amino acid analyses of the epimysial ASC samples via gas chromatography showed no differences in the levels of aspartic, serine or hydroxyproline, amino acids which may be involved in the ester type of cross‐links. Results of chemical estimation of the ester type of cross‐links indicated that the proportions of esters in the various ASC samples were similar. The amount of lysine was found to be significantly higher (P < 0.05) in epimysial ASC from tough meat compared to tender meat, suggesting an increased potential of the aldehydic‐type of cross‐link, which is formed via an aldol condensation of two aldehydes derived biosynthetically from lysine. This was strengthened by the results obtained in the chemical estimation of the aldehydic‐type of cross‐link, in that the epimysial ASC of tough meat contained significantly more aldehyde than did that of tender meat (P<0.05).
EFFECT OF TEMPERATURE ON VISCOSITY OF FRUIT JUICES AND PUREES
Authors: SARAVACOS G. D.
Published: August 2006

SUMMARY: The viscosities of selected fruit juices and purees were measured with a coaxial‐cylinder viscometer in the temperature range 20–70°C. Depectinized apple juice and Concord grape juice were Newtonian fluids at all concentrations and their viscosity decreased considerably at higher temperatures. Cloudy apple and orange juices changed from Newtonian to pseudoplastic at concentrations higher than 50 and 20° Brix. respectively. Temperature had a smaller effect on viscosity of cloudy juices than of clear juices. The apparent viscosity of fruit purees (pseudoplastic fluids) decreased slightly at higher temperatures. The activation energy for flow increased with the juice concentration and decreased with the presence of suspended particles in the fruit product. The data and conclusions are useful in the design and operation of efficient food‐processing equipment.
PRODUCTION AND PROPERTIES OF PENCILLIUM ROQUEFORTI LIPASE
Authors: EITENMILLER R. R. , VAKIL J. R. , SHAHANI K. M.
Published: August 2006

SUMMARY: A Penicillium roqueforti strain produced maximal amounts of lipase when grown in 0.5% casitone‐1% Proflo broth, pH 5.5, at 27°C. Addition of butteroil, com oil or olive oil to the growth medium inhibited the lipase production. Under pH stasis the partially purified lipase of P. roqueforti had an optimum pH of 8.0 and an optimum temperature of 37°C. Maximum lipolytic activity occurred with 5% butteroil emulsion as the substrate. Manganese chloride and magnesium chloride stimulated the enzyme activity. Calcium, sodium and potassium sale had no appreciable effect on lipolysis; silver, mercury and zinc salts were inhibitory. The lipase was thermolabile, being inactivated completely within 10 min at 50°C. The lipase hydrolyzed tributyrin, tricaprylin, tricaprin, tripropionin and triolein in decreasing order.
PYROGLUTAMYL DIPEPTIDES IN MUSHROOM, AGARICUS CAMPESTRIS
Authors: ALTAMURA M. R. , ANDREOTTI R. E. , BAZINET M. L. , LONG L.
Published: August 2006

SUMMARY: A small fraction, containing evidence for the presence of pyroglutamyl dipeptides and an N‐pyroglutamylhexosamine. was isolated from the edible, commercial mushroom. Agaricus campestris. Upon hydrolysis, this isolate liberated a copious amount of glutamic acid, together with smaller quantities of other amino acids and a hexosamine. Analyses of the unhydrolyzed and hydrolyzed portions of the fraction by an automatic amino acid analyzer revealed the identities and quantities of the compounds released. Additional chemical and physical methods of analysis gave supporting evidence for the presence in the mushroom in addition to proline and pyroglutamic acid of the pyroglutamyl dipeptides of threonine, aspartic acid, valine, leucine, citrulline, phenylalanine, glycine, alanine, glutamic acid and proline and also of the amino acid sugar, N‐pyroglutamylglucosamine. Pyroglutamylcitrulline and N‐pyroglutamylglucosamine were tentatively identified. The first 6 dipeptides are reported for the first time. A mechanism is proposed for the enzymic biosynthesis of the pyroglutamyl dipeptides in the mushroom. Results of the present work shed additional light on the complex nature of the higher basidiomycetes.
LOW‐TEMPERATURE, LONG‐TIME HEATING OF BOVINE MUSCLE 1. Changes in Tenderness, Water‐Binding Capacity, pH and Amount of Water‐Soluble Components
Authors: LAAKKONEN E. , WELLINGTON G. H. , SHERBON J. N.
Published: August 2006

SUMMARY: Relationships between the tenderness of very slowly cooked meat and its waterholding capacity, pH and the amount of water‐soluble components were studied. Beef muscle portions from the longissimus, semitendinosus and rectus femoris muscles were heated under fixed temperature programs with samples from each analyzed at 1‐hr intervals between the 3rd and the 10th hr of heating. Weight losses after holding at the final temperature to the 24th hr were determined. During the first 4 hr of heating there were only minor changes in tenderness. The major decrease in shear values occurred between the 4th and 6th hr, when the meat was warming from 50‐60°C. The weight losses increased rather linearly to the 7th hr and remained constant for the longissimus and the semitendinosus muscle. The pH values gradually increased during heating. During the first 3 hr of heating, up to 45°C, there was only a slight decrease in the amount of the water‐soluble fraction. During the following 3 hr. from 45 to 58°C, the water‐soluble fraction decreased more rapidly and the decrease was only slight during a following 4‐hr holding period. After 6 hr of heating to 60°C there were still uncoagulated water‐soluble proteins. These studies indicate that the final temperature of meat has great influence on tenderness and weight loss. The significance of the shrinkage of collagen in long‐time, low‐temperature cooking is considered.
POULTRY PRODUCT QUALITY. 1. Compositional Changes During Cooking of Turkey Roasts
Authors: MacNELL J. H. , DIMICK P. S.
Published: August 2006

SUMMARY: White and dark turkey roasts, averaging 7.1 and 3.1 lb respectively, were made with meat taken from selected samples of the various entries in the Pennsylvania Turkey Random Sample Meat Test. Additional róasts were made from sample birds from the University research flock. Roasts were wrapped in aluminum foil, then cooked in a Telkes oven. All roasts were cooked to an internal temperature of 170°F. There were no sex differences in cooking losses except when skin was examined separately. Differences in cooking losses were observed in the breast meat but not in the thigh meat of roasts prepared from Bronze and White turkeys. Losses were higher for breast meat than for thigh meat. There was an indication that size of bird was not a significant factor in determining percentage cooking losses for breast and thigh roasts. When fat drippings from cooked skin were analyzed for carbonyl content high skin yielding males were characterized by the high concentration of the 2‐enals in relation to the methyl ketones. Low skin groups consisted mainly of methyl ketones.
POULTRY PRODUCT QUALITY. 2. Storage Time‐Temperature Effects on Carbonyl Composition of Cooked Turkey and Chicken Skin Fractions
Authors: DIMICK P. S. , NEIL J. H. MAC
Published: August 2006

SUMMARY: The carbonyl compounds in cooked turkey and chicken skin fractions after storage were isolated as their 2,4‐dinitrophenylhdrazones. The monocarbonyl class was separated into methyl ketones, 2‐enals and 2,4‐dienals and measured spectrophotometrically. The turkey skin residue fraction contained higher concentrations of carbonyls than did the chicken samples. The oil extract from the skin of both groups was similar in carbonyl concentration. Lower storage temperature dramatically lowered the development of carbonyls. Phospholipid phosphorus determinations indicated the residue contained high levels of polar lipid; whereas, negligible amounts were in the oil. Thin‐layer chromatography of the carbonyl classes from the skin residue indicated mainly C7‐C9 2‐enals and C8, C9 2, 4‐dienals in the unsaturated aldehyde fractions. Changes in fatty acid composition of the residue polar lipids during storage suggested linoleic and arachidonic acids as the probable substrates in autoxidative deterioration.
Pectin Methyl Esterase Activity in Southern Peas (Vigna sinensis)
Authors: COLLINS JIMMIE L.
Published: August 2006

SUMMARY: Pectin methyl esterase (PME) activity was investigated in vitro in Southern peas (Vigna sinensis). Experiments were conducted to determine the effect of NaCl concentration, pH, temperature, maturity, frozen storage and rinsing the peas on PME activity.

The optimum salt level for maximum PME activity in the Purple Hull Pink Eye (PHPE) and Princess Ann (PA) varieties was ascertained to be 0.25 M. The pH optima were: PHPE, 8.5; and PA, 7.5 to 8. The remaining studies were made using peas of the PHPE variety which were harvested at 3 stages of maturity. Maximum enzymatic activity occurred at 50°–60°C. Partial inactivation occurred at 65°C. The mean Q10 was 1.35 over the range of 30°–50°C.

PME activity was dependent upon the maturity of the peas. The most immature peas had an activity level about 2.5 times that found in the most mature peas. Peas subjected to frozen storage had a higher activity than the fresh peas; the increased activity was more pronounced in the more mature peas.

Rinsing the peas removed significant amounts of the enzyme. A greater proportion of PME was removed from the more immature peas than from the more mature ones. With the immature, frozen peas PME activity was reduced 22.7% by rinsing; whereas, in the fresh counterpart the reduction was 11.1%. The rinse water from frozen peas contained more PME activity than did rinse water from fresh peas. Also, the activity in rinse water from the most immature peas was about 2.7 times that from the most mature ones. Upon standing, PME activity in the slurries prepared from frozen peas continued to increase up to 3–4 hr.
Pasteurization of Pacific Oysters by Radiation: Post‐Mortem Changes in Nucleotides During Storage at 0‐2°C
Authors: GUARDIA ENRIQUE J. , DOLLAR ALEXANDER M.
Published: August 2006

SUMMARY: The concentration of nucleotides was lower in the adductor muscle of the oyster (1.64 μmoles/g) than in the remaining dark tissues of the oyster (2.75 μmoles/g). The concentration was less in the whole oyster meats (2.87 μmoles/g) than is usually found in fish muscle, or other marine invertebrates.

In addition to the adenine nucleotides and inosine monophosphate, uridine triphosphate, guanosine triphosphate, guanosine diphosphate, guanosine monophosphate and guanosine diphosphate‐mannose were found in the fresh oysters. Samples collected in summer had greater concentrations of nucleotides than similar winter samples. lnosine monophosphate formed rapidly from adenosine triphosphate during storage at 0°–2°C, while the turnover rate of inosine monophosphate was slow and reflected low 5′‐nucleotidase activity. Hypoxanthine, inosine, guanosine, guanine and uracil were formed during ice storage. The nucleotide breakdown in oysters was not changed by 2 mrads of radiation dose. Total nucleosides and free bases increased during storage of both unirradiated and irradiated samples. During the latter part of the storage period the concentrations of nucleosides and free bases were considerably greater in the irradiated samples. This difference probably is due to the utilization of these compounds by bacteria in the un‐irradiated samples. After 15 days of storage bacteria had increased to more than 10’organisms per g, while the counts for irradiated samples were very low (less than 103 per g).
Metmyoglobin Formation in Beef Stored in Carbon Dioxide Enriched and Oxygen Depleted Atmospheres
Authors: LEDWARD D. A.
Published: August 2006

SUMMARY: A spectroreflectometric technique was used to determine the relative percentages of three myoglobin pigments, reduced myoglobin, oxymyoglobin and metmyoglobin at the surface of fresh beef. It was shown that, at constant humidity, the formation of metmyoglobin in beef was maximal at 6 + 3 mm Hg of oxygen at 0°C and 7.5 ± 3 mm Hg at 7°C for semitendinosus muscles. Carbon dioxide concentrations of 10% and higher had negligible effect on the formation of metmyoglobin, provided the oxygen pressure was above about 5%. At high partial pressures of carbon dioxide, absorption of carbon dioxide increased and the pH of the surface decreased. In air, the formation of metmyoglobin varied widely from muscle to muscle.