bluuebunny/crossref_metadata_2025 huggingface dataset:
CHANGES IN SOME MONOCARBONYL CLASSES DURING PROCESSING AND STORAGE OF SWEET POTATO FLAKES
Authors: LOPEZ ANTHONY , WOOD C B. , BOYD E. N.
Published: August 2006

Dehydrated sweet potato flakes were prepared in a pilot plant by (1) peeling and comminuting fresh sweet potatoes; (2) heating sweet potato puree to 755°C and holding at that temperature to allow naturally present amylases to convert a certain proportion of the starch into sugars; (3) heating puree to 105°C to inactivate enzymes; (4) atmospheric drum drying and flaking; and (5) packing flakes in cans under N2 atmosphere Total monocarbonyls in fresh sweet potatoes generally increased with time of storage of the roots During processing of freshly dug sweet potatoes into dehydrated flakes, monocarbonyls increased as processing progressed. During processing of “cured,” and of up to 4‐months' stored sweet potatoes the content of monocarbonyls peaked during conversion of starch to sugars, and decreased after heating to 105°C prior to drum drying. Levels of saturated aide hydes and of methyl ketones were also highest during amylolysis. During storage of the packaged flakes at 27°C for 128 days, total monocarbonyl content remained rather constant, while saturated aldehydes increased and methyl ketones decreased. At 45°C storage temperature, total monocarbonyls and saturated aldehydes showed a marked increase, while ketones decreased. There was a slight net increase in CO2 and O2 and a slight decrease in N2 in the gas present in cans of flakes stored for 1 yr at 24°C. After 12 months storage, 0.026% CO was found in the dehydrated sweet potato flake product monocarbonyls, particularly aldehydes, are probably a factor in off‐flavor development during storage.
ISOLATION OF LIPOFUSCIN‐LIKE FLUORESCENT PRODUCTS FROM RIPENING BANANA FRUIT
Authors: GUIRE Y. P. MA , HAARD N. F.
Published: August 2006

Ripening banana fruit contains water‐insoluble pigments which have a molecular weight in excess of 4000 and a fluorescence spectrum identical to lipofuscin or age pigments. The pigments were not decomposed by irradiation with ultraviolet light. The flourescent substances increased linearly in the peel and quadratically in the pulp during the course of ripening. It is suggested that the fluorescent substances are products of membrane lipo‐protein peroxidation like the lipofuscin pigments identified in animal tissues.
THE FATE OF NITRITE: REACTION WITH PROTEIN
Authors: WOOLFORD G. , CASSENS R. G. , GREASER M. L. , SEBRANEK J. G.
Published: August 2006

This paper presents results showing that one of the major pathways for loss of nitrite in cured meats may be through reaction with nonheme protein. Incorporation of the stable isotope 15N from nitrite is shown to occur in both bovine serum albumin and the muscle protein myosin, at pH's below and at those found in cured meat. In bovine serum albumin solution at pH 5.5 and at 20°C, 60% loss of added nitrite (200 ppm) occurred within 1 wk and almost half of the lost nitrite nitrogen was recovered as 15N chemically bound to the protein. Analysis of the reaction products of nitrite and myosin showed that, under the conditions used, 10–20% of the incorporated nitrogen was present as 3‐nitrotyrosine. Several other products were found in acid hydrolysates of protein containing bound nitrite, but these did not appear to quantitatively account for the remainder of the incorporated nitrite.
COMPOSITION AND PROPERTIES OF AN ANIMAL PROTEIN ISOLATE PREPARED FROM BONE RESIDUE
Authors: YOUNG LOUIS L.
Published: August 2006

A protein isolate was prepared from the bone residue of mechanically deboned chicken necks and backs. Typically, the isolate contained 60–65% protein, 23–25% lipid, 5–10% ash and 4–6% moisture. Solubility and emulsifying capacity of the isolate were enhanced at elevated pH and ionic strength and in the presence of polyphosphates. The latter were effective in improving emulsifying capacity when used in combination with NaCl but not when used alone.
COTTAGE CHEESE FROM ULTRAFILTERED SKIM MILK
Authors: MATTEWS M. E. , SO S. E. , AMUNDSON C. H. , HILL C. G.
Published: August 2006

Ultrafiltration of skim milk was conducted at 4.4, 21.0 and 49.0°C to provide retentates for cottage cheese trials. Fractionation at 21.0 and 49.0°C improved initial permeation flux rate (PR) by 50 and 300%, respectively, over that observed at 4.4°C. Rates of decline of PR de creased with increasing temperature. Retentate ratios of undenatured whey protein nitrogen:casein nitrogen (CN) and proteosepeptone:CN were unchanged during ultrafiltration whereas nonprotein nitrogen:CN declined at each temperature. Calcium concentration of permeate was 1–2% less at 49.0 than 4.4°C because of increased calcium concentration of retentate at higher temperature. Large curd, creamed cottage cheese was prepared successfully from each retentate, cooking temperature and/or time being reduced because of initially firmer curd. Intermediate temperature (21.0°C) processing induced rapid microbial proliferation after > 2 hr. The utility of ultrafiltration as a preconcentration step for continuous cottage cheese production is discussed.
USE OF DIAMIDE IN DETERMINING THE SHELF LIFE OF REFRIGERATED CHICKEN
Authors: WAN CHIU‐CHI , COLLINS E. B. , BRANT A. W.
Published: August 2006

A study was done to determine if a relationship exists between plate counts determined on trypticase soy agar containing diamide and the shelf life of refrigerated chicken carcasses. Results show that determining plate counts with TSA containing 0.05% diamide appears useful as a means of predicting shelf life of raw chicken and possibly other fresh meats stored under refrigeration.
EVALUATION OF A CALCIUM ALGINATE COATING AND A PROTECTIVE PLASTIC WRAPPING FOR THE CONTROL OF LAMB CARCASS SHRINKAGE
Authors: LAZARUS C. R. , WEST R. L. , OBLINGER J. L. , PALMER A. Z.
Published: August 2006

Ninety lamb carcasses were evaluated for shrink loss, microbial growth and temperature reduction following treatment with: (1) an edible calcium alginate coating, Flavor‐Tex®; (2) plastic wrap; or, (3) no treatment (control). Lambs (n = 30) were slaughtered on three consecutive days with 10 carcasses/day being randomly assigned to each treatment. Carcasses receiving the edible coating were significantly (P < 0.05) lower in 24‐hr shrinkage loss (1.55%) than the controls (2.77%); however, those in plastic wrap had the least amount of shrinkage (1.20%), and maintained this advantage through 7 days postmortem. Total surface microbial counts from the sirloin area indicated a significant (P < 0.05) reduction at day 5 and 7 for the alginate coated carcasses, with the plastic wrap carcasses having the highest counts on all days. Internal leg temperature reduction (chilling) was essentially uniform at the end of a 24‐hr chill at 2°C regardless of treatment. No significant differences were observed between treatments for cooking loss, flavor, juiciness, off‐odor or overall acceptability.
AFLATOXIN CONTENT AND SKIN REMOVAL OF SPANISH PEANUTS AS AFFECTED BY TREATMENTS WITH CHEMICALS, WATER SPRAY, HEATED AIR, AND LIQUID NITROGEN
Authors: PAULSEN M. R. , BRUSEWlTZ G. H. , CLARY B. L , ODELL G. V. , POMINSKI J.
Published: August 2006

Unshelled Spanish peanuts contaminated with aflatoxin were shelled and treated with forced heated air, liquid nitrogen, H2 O2, HCl, sodium oleate, and water spray. After passing through a whole nut blancher the aflatoxin content and percentages of blanched (skin removed) and whole kernels were determined Blanching percentages were significantly higher for sodium oleate, water spray, liquid nitrogen, and H2 O2 than for HCl or heat treatments. The heat treatment produced the highest percentage of whole kernels. In most tests, the unblanched kernels contained higher levels of aflatoxin than those that blanched fully. The treatments which were most effective in producing low levels of aflatoxin in the blanched kernels were H2O2, water spray and HCl.
A pork slurry system for studying inhibition of Clostridium botulinum by curing salts
Authors: RHODES ANNETTE C. , JARVIS B.
Published: August 2006

A meat slurry system is described for studying the effects of curing agents on growth and toxin production by Clostridium botulinum. In developing the system a prime objective was good reproducibility for pre‐selected levels of salt (NaCl), sodium nitrite, fat and pH value. This objective was achieved and large numbers of replicate samples were prepared and dispensed with a minimum of technological equipment. Results obtained in the system are compared with those obtained using pork mince packed into bottles (Ashworth, Hargreaves & Jarvis, 1973). Results of preliminary studies show little effect of varying the severity of thermal processes on the inhibitory action of sodium nitrite in the presence of sodium chloride, but some variation in inhibition was observed with different batches of meat used to prepare the slurries.
The automated determination of volatile bases (trimethylamine, dimethylamine and ammonia) in fish and shrimp
Authors: RUITER A. , WESEMAN J. M.
Published: August 2006

The automated method for the determination of trimethylamine (TMA) in fish and shrimp extracts, which is based upon the colour change of an indicator solution into which TMA vapours are injected, was further improved. Methods for the automated determination of dimethylamine (DMA) and ammonia in extracts were developed and elaborated. the accuracy and precision of the automated TMA and DMA determination equal those of the gas chromatographic determination of these amines described previously.

Both TMA and DMA can be analysed at a speed of thirty samples in an hour, whereas the rate of analysis for NH3 is sixty per hour.
The effects of fibre, starch damage and surfactants on the baking quality of wheat/cassava composite flours
Authors: HUDSON B. J. F. , OGUNSUA A. O.
Published: August 2006

Sieving of cassava flour yielded a fraction suitable for use in wheat/cassava bread. the degree of starch damage of the cassava flour had no effect on baking quality. Cassava flour did not exhibit diastatic activity, nor did its presence affect the diastatic activity of wheat flour. However, the addition of 0.25% of malt to the composite flour caused an increase in loaf volume. Partial replacement of wheat flour by cassava flour, therefore, is limited mainly by the consequent deficiency of diastatic enzymes. Calcium stearyl lactylate, at 2/7% of flour weight caused a significant increase in loaf volume, but the addition of glyceryl monostearate had no effect on loaf volume.
The proteins of intermediate moisture meat stored at tropical temperature
Authors: OBANU Z. A. , LEDWARD D. A. , LAWRIE R. A.
Published: August 2006

Intermediate moisture (i.m.) meats prepared from selected muscles of two ewes, one sow, five hens and two goats all underwent protein breakdown and complexing reactions during storage at 38°C. the relative rates of these reactions varied from sample to sample. These reactions included colour changes culminating in the formation of ‘Maillard’ type brown pigments. This discolouration may well limit the storage life of these meats. It was apparent within three to nine weeks at 38°C.

At 28°C all the reactions occurred far more slowly.

One bull muscle which was also examined proved atypical in that although proteolysis occurred there was no evidence of any complexing and, up to nine weeks’ storage, no evidence of any non‐enzymic browning.
Freeze dehydrated compressed sour cherries
Authors: DO J. Y. , POTEWIRATANANOND S. , SALUNKHE D. K. , RAHMAN A. R.
Published: August 2006

The stability of anthocyanin in freeze dehydrated compressed sour cherries during storage at 21 and 38°C were studied by extraction of pigments, thinlayer chromatography and spectrophotometry. Total anthocyanin contents of freeze‐dried compressed sample decreased from 9.28 mg/100g to 5.04 and 1.10mg/100g, respectively, after six months at 21 and 38°C. Cyanidin‐3‐(2G‐xylosylrutinoside) was the least stable pigment among the seven pigments identified.
Corrosion of tinplate by citrus juices
Authors: MAHADEVIAH M. , GOWRAMMA R. V. , EIPESON W. E. , SASTRY L. V. L.
Published: August 2006

Juice from the Satsuma Mandarin variety of oranges which was free from bitterness with less acidity gave more corrosion as compared with the juice from Coorg Mandarin, Mandarin Imperial, Tangerine Dancy and Washington Navel. Bitter principles present in the orange juice were found to act as inhibitors of corrosion. Limonin acted as inhibitor of corrosion, while hesperidin did not show any effect. Among different fractions of orange juice, the organic acid fraction contributed towards corrosion.
Some chemical changes in fish silage
Authors: BACKHOFF HANS P.
Published: August 2006

During ensilage of cod in the presence of 3% (w/w) formic acid, the enzymes mainly responsible for the liquefaction were those of the gut, skin and other parts of the fish other than flesh; those of the last were only marginally implicated. During the storage of the silage the formation of non‐protein nitrogen (free amino groups, volatile bases, and polypeptides) was measured. Silages were produced using whole cod and herring. Tryptophan was found to be partially lost: during ensilage and storage, the values for available lysine remained constant.
Eating quality of hot deboned beef
Authors: DRANSFIELD E. , BROWN A. J. , RHODES D. N.
Published: August 2006

One side from each of six beef carcasses was treated in a standard commercial fashion (control) whilst meat from the other sides was removed and packed either as joints or muscles within 3 hr after stunning (hot deboned). The eating quality of the meat was assessed by laboratory and consumer taste‐panels and the texture determined instrumentally. When the meat was held at 10°C until the development of rigor mortis, the ultimate eating quality was equal to that of the controls. Ageing enhanced the tenderness of hot deboned meat.
Technical note: Aseptic technique for obtaining sterile beef tissue
Authors: BUCKLEY J. , MORRISSEY P. A. , DALY MICHELE
Published: August 2006

The changes which take place in meats during refrigerated storage may be caused by external bacterial sources as well as by naturally occurring enzymatic and chemical reactions. To obtain an understanding of these changes and of their relative importance in meat spoilage, it is necessary to differentiate between the bacterial‐induced changes and those due to muscle autolysis. The success of such a study depends upon the method used for obtaining sterile tissue. The size of the animal from which the muscle tissue is to be taken determines to a great extent the procedure and precautions to be used. The larger the animal the more difficult it is to obtain sterile tissue and the more expensive the study becomes.
Studies of mango processing
Authors: COOKE R. D. , ALLISON C. J. , BALDRY J. , CAYGILL J. C. , FERBER C. E. M. , KANAGASABAPATHY L. , VEALE M. J.
Published: August 2006

Alphonso mango slices in syrup were frozen under thirteen different conditions, stored for three months at −28°C and the quality of the products assessed chemically, microbiologically and organoletically. the quality was insensitive to the freezing rate (cryogenic freezing, blast freezing or domestic deep freezing) and to the addition of 0.1% vitamin C to the cover syrup. Presoaking in CaCla prior to pasteurization caused a marked firming of the slices. Soaking the slices in acidic syrup followed by mild pasteurization greatly decreased the microbial counts but had an adverse effect on flavour. Fruit frozen in 40°Brix syrup had a better flavour than that frozen in 20° Brix syrup. Acceptable slices with good nutrient retention were produced by freezing in 40° Brix syrup using a domestic deep freezer.
A comparison of methods for measuring the volatile components of apple fruits
Authors: KNEE MICHAEL , HATFIELD STEPHEN G. S.
Published: August 2006

Volatile compounds produced by apple fruits (Malus domestica, Borkh.) were separated and estimated by gas chromatography. Procedures were devised for estimation of compounds in air surrounding whole apples and discs of apple tissue, and in apple juice. Concentrations of volatiles in air passing over apples were influenced by tissue permeability, concentrations in peel or cortex, and the extent of enzymic hydrolysis of esters passing through the peel. the complexity of these effects prevents assessment of the importance of compounds in apple flavour based on their concentrations around whole fruit. the ratios of concentrations established in air around cortical discs to concentrations in juice were similar to air/water partition coefficients observed for standard compounds. Measurement of concentrations above cortical discs is simple and sensitive and can be related to flavour, through the olfactory threshold concentrations of the compounds detected.
Determination of freezing and thawing times in the centre of blocks of meat by measurement of surface temperature
Authors: JAMES STEPHEN J. , BAILEY C. , ONO S.
Published: August 2006

A mathematical model based on a theoretical analysis of the pattern of heat flow was used to produce a set of freezing and thawing curves at various depths through an infinite slab of lean meat. Analysis of these curves indicated that the end of the freezing or thawing plateau at the block centre should be reflected in a change in the temperature‐time gradient (λTs/λt) at or near the surface.

This change was subsequently demonstrated experimentally, and a method has been devised which enables the freezing or thawing time at the centre of a block of meat to be determined by means of a probe inserted just under the surface of the block.
The application of amino acid analysis to the determination of the geographical origin of honey
Authors: DAVIES A. M. C.
Published: August 2006

Honeys from four geographical areas were characterized by a selection of sixty amino acid ratios, calculated from amino acid analysis data. Tests were carried out on sixteen samples of honey which came from these characterized areas using the selected amino acid ratios and on a reduced set of ratios in which the number of correlated ratios had been reduced. Fifteen samples were correctly identified by the full ratio set and fourteen samples by the reduced set. No sample failed both tests. Forty‐two honeys which did not come from these areas were also tested and only one sample was incorrectly identified as originating from a characterized area.

These results support the proposal that amino acid analysis could be used as an instrumental method of determining the geographical source of a honey, in place of the highly subjective method of pollen analysis. However, further work is required before the method could be recommended for official use.

The possibility of applying the same techniques to other problems of food source identity is noted.
The detection and estimation of soya protein in food products by isoelectric focusing
Authors: LLEWELLYN J. W. , FLAHERTY B.
Published: August 2006

The analysis of non‐meat protein in meat products by the technique of isoelectric focusing in polyacrylamide gels is described. When laboratory prepared pork sausages containing known amounts of added soya protein isolate were analysed, 1% (of fresh sausage weight) added isolate could be detected. At low levels of added isolate (<5% fresh sausage weight) the technique could only be considered semiquantitative, but at higher levels of added isolate (>5% fresh sausage weight) better quantitation was possible. the technique cannot be applied to the analysis of products that have undergone extensive heat treatment during manufacture, however, due to denaturation of the soya protein.
POLYPHENOLIC COMPOUNDS IN THE PULP OF Mangrifera indica L.
Authors: SAEED A. R. , KARAMALLA K. A. , KHATTAB A. H.
Published: August 2006

Polyphenolic compounds were isolated from the pulp of three varieties of mangoes by ethyl acetate extraction. The compounds were separated by two‐dimensional paper chromatography. The individual compounds were identified by Rf values, fluorescent behavior and degradation products. Gallotannin, m‐digallic acid, gallic acid, unknown hydrolyzable tannin and mangiferin were identified. Phenolic compounds which are known to be responsible for astringency and browning in fruits were not detected by this extraction procedure.
CASHEW PHOSPHOLIPIDS
Authors: MAIA G. A. , BROWN W. H. , WHITING F. M. , STULL J. W.
Published: August 2006

Phospholipids were isolated by silicic acid column chromatography (CC) from cashew nuts and cashew apple juice. Component phospho‐lipids were separated by two‐dimensional thin‐layer chromatography (TLC). Cashew nut oil and cashew apple juice lipids gave 9 and 11 TLC spots, respectively, positive to the specific molybdenum spray. Phos‐phatidyl choline (PC) and phosphatidyl ethanolamine (PE) isolated from cashew nut lipid phospholipids were analyzed for fatty acid composition. The major fatty acids in PE and PC were palmitic, stearic, oleic, and linoleic representing 85.3% of the total in PE and 73.3% in PC.
Autolysis and proteolytic activity of cod viscera
Authors: RAA JAN , GILDBERG ASBJØRN
Published: August 2006

This paper describes the autolysis of cod viscera and discusses the importance of protease activity for this process. Autolysis yields a lipid phase, an aqueous soluble phase which contains much protein but very little lipid, and an insoluble sediment of protein and lipid. the amino acid composition of the soluble phase differs markedly from that of the sediment; the latter does not contain hydroxyproline and has relatively high levels of aromatic amino acids and of cysteine/cystine. the natural digestion process in the alimentary tract of cod also leaves an insoluble protein with a similar amino acid composition. the sediment which remains after autolysis is very resistant to the activity of the proteases present in the viscera. the pH curve for protease activity with a model substrate does not correspond to the pH curves for autolysis.
CHEMICAL, PALATABILITY AND COOKING CHARACTERISTICS OF NORMAL AND LOW QUALITY PORK LOINS AS AFFECTED BY FREEZER STORAGE
Authors: KEMP JAMES D. , MONTGOMERY RICHARD E. , FOX J.D.
Published: August 2006

Loins of normal (Wisc. score 3) and low (Wisc. score 1) quality were compared for pH (fresh only), thiamine (fresh and 120 days), organoleptic and tenderness scores and cooking losses while fresh and after 60 and 120 days' freezer storage. pH was significantly lower for PSE than for normal loins. Thiamine content also was lower for the PSE loins and decreased for both quality groups during storage. TBA values indicated a greater degree of rancidity for PSE loins, but contrary to expected outcome they tended to decrease with freezer storage. Normal loins received significantly higher organoleptic evaluation scores for flavor, juiciness and overall satisfaction. On the other hand, PSE loins tended to be slightly more tender. Tenderness increased with freezer storage time. There were no differences in flavor, juiciness or overall satisfaction scores due to freezer storage. PSE loins had significantly more total cooking and evaporative loss than normal loins. There was a significant increase in evaporative loss as storage time increased.
EFFECT OF ICE STORAGE ON MICROBIOLOGICAL AND CHEMICAL CHANGES IN SHRIMP AND MELTING ICE IN A MODEL SYSTEM
Authors: Ill; E. F. COBB , VANDERZANT C. , HANNA M. O. , YEH CHIA‐PING S.
Published: August 2006

In ice stored shrimp, Vibrio, Pseudomonas and/or Moraxella‐Acineto‐batter species were initially dombant. After 12–15 days, Vibrio sp. had disappeared and Pseudomonas sp. predominated followed by Moraxella‐Acinetobacter sp. The mean increase in aerobic plate count over this period was 2.2–2.4 log. In the melting ice (drip) Moraxella‐Acine‐tobacter, Pseudomonas, Flavobacterium, Micrococcus, Vibrio, Corynebacterium, Staphylococcus, Alcaligenes and yeasts were present initially. After 9–13 days, Vibrio, Flavobacterium and Micrococcus sp. could not be detected in the drip, whereas Pseudomonas or Moraxella‐Acinetobacter sp. remained present or in some cases increased. The mean increase in bacterial count of the drip was 3.4 Jog. Considering the loss in TVN in the drip, there was a net increase in TVN ranging from 6.7–60.1 mg N/100g. AA‐N levels in shrimp decreased during storage. The TVN‐AA‐N ratio of drip did not increase significantly until bacterial levels reached 10 per ml drip.
PROTEIN CONTENT AND AMINO ACID COMPOSITION IN GROATS AND HULLS OF DEVELOPING OATS (Avena sativa)
Authors: POMERANZ Y. , SHANDS H. L. , ROBBINS G. S. , GILBERTSON J. T.
Published: August 2006

Protein content and ammo acid composition were determined in groats and hulls of three oat cultivars harvested at four stages of development. Protein content was slightly higher in mature than in immature groats. In the hulls, protein content decreased during development to about one‐third the content of immature hulls. The large decrease in protein content of the hulls was accompanied by little change in amino acid composition. In the groats, however, there were consistent and large decreases in concentrations of lysine, threonine and aspartic acid and an increase in glutamic acid. The results suggest that in addition to deposition of storage protein in the groat, ammo acids are translocated from the hulls to the groats.
ILLINOIS PROCESS FOR PREPARATION OF SOYMILK
Authors: NELSON A. I. , STEINBERG M. I. , WEI L. S.
Published: August 2006

A beverage consisting of water, whole soybeans (including hulls), sugar and flavor has been developed. Preparation includes soaking and then blanching the whole soybeans in 0.5% sodium bicarbonate, grinding with water in a hammermih, heating the slurry to 200° F, homogenizing, neutralizing, dilution, addition of sugar and flavor, pasteurizing and rohomogenizing. Enzyme inactivation by blanching prior to grinding of soaked beans was found to completely prevent formation of painty (oxidized) flavor and result in a bland flavored product. Trypsin inhibitors were also inactivated by blanching. A sufficient degree of tender‐ization of soybean tissue during the soak and blanch treatments was necessary to obtain good mouth feel and colloidal stability. Homogenizing conditions such as temperature and pressure were also important; when the soybeans had been blanched to a LEE‐Kramer Tenderometer reading of 300 lb or below and homogenization was done at 200°F and 3500 psi, the resulting beverage showed zero separation after 2 months refrigerated storage. Dilution to below 1% protein had no effect on colloidal stability. Coulter Counter measurements of the beverage indicated that 81% of the particles fell between 3.4‐7.3 microns which is larger than the defined colloidal particle range. Recoveries of protein and total solids based on the raw soybean were 99% and 90%, respeo tively.
ENZYME USE TO REDUCE VISCOSITY AND INCREASE RECOVERY OF SOLULE SOLIDS FROM CITRUS PULP‐WASHING OPERATIQNS
Authors: BRADDOCK R. J. , KESTERSON J. W.
Published: August 2006

Soluble solids (SS) recovered by countercurrent washing of citrus juice pulp are concentrated by evaporation and sold primarily for use in beverage bases and other food uses. On a pilot plant scale, treatment of the finisher pulp with pectolytic enzymes resulted in increasing the yield of recoverable SS from 65–80 kg SS/ton pulp (oranges) and from 45–50 kg SS/ton (grapefruit). High viscosity of pulp‐wash liquids and other citrus processing liquids was found to be a deterrent during concentration by evaporation. Enzyme‐treated liquids were concentrated in a medium‐temperature evaporator to over 70° Brix and relative viscosities in the range of 1700–2200 centipoises; however, due to gel formation, nontreated liquids had to be pumped out of the evaporator at 25–35° Brix with a relative viscosity of over 20,000 centipoises. Careful use of enzyine to increase SS yields or lower viscosity during pulpwashing did not adversely affect the °Brix, acid, pH or clouding ability of the concentrated pulp‐wash.
PEELING OF CHINESE WATERCHESTNUTS
Authors: LEEPER G. F. , WILLIAMS A. K.
Published: August 2006

The extensive hand labor required in peeling Chinese waterchestnut corms has dicouraged their production in this country. After cutting the apical and basal ends from the corms, the peel was removed by softening in hot alkali, followed by wet brushing. The lignaceous pigmentation which stains the corms during peeling was decolorized by treatment with hydrogen peroxide. A nomograph to optimize peel softening in terms of alkali concentration, time and temperature is presented. This nomograph shows solutions to the equation 6.76 = [0.038 (°F) ‐ (6.51/% NaOH) ‐ (9.81/min of treatment)].
MICROBIOLOGY OF PALE, DARK AND NORMAL PORK
Authors: REY C. R. , KRAFT A. A. , TOPEL D. G. , PARRISH F. C. , HOTCHKISS D.K.
Published: August 2006

Pale, soft, exudative (PSE), dark cutting, and normal colored pork were compared to determine differences in susceptibility to microbial growth. Chops were packaged and stored under simulated retail conditions. Color, marbling, pH, numbers of total aerobic mesophiles, psychrotrophs, proteolytic and lipolytic bacteria and fluorescent Pseudomonas and incidence of Salmonella and coagulase positive Staphylococcus were recorded for pork chops as storage time progressed. Data were statistically analyzed. Differences in pH between PSE and normal chops, after aging, were significant, and dark chops had significantly higher pH values than normal chops. Development of microorganisms during storage was influenced by pH. Most rapid growth of organisms occurred on dark meat and slowest bacterial growth on PSE pork, although exudative conditions of the latter provided the highest expressible juice. pH of the meat also seemed to have a selective action on the microflora. Marbling of the meat did not influence growth of lipslytic bacteria. Relevance of various stages of processing as sources of contamination for the meat is discussed.
RELATIONSHIP OF Vibrio parahaemolyticus IN OYSTERS, WATER AND SEDIMENT, AND BACTERIOLOGICAL AND ENVIRONMENTAL INDICES
Authors: THOMPSON C. A. , VANDERZANT C.
Published: August 2006

Of 153 samples of oysters, water and sediment tested 94 (61.4%) were positive for V. parahaemolyticus. In 87% of the positive oyster samples the level of V. parahaemolyticus was < 100 per g. Standard Plate Counts of oysters ranged from 5.0 × 103 to > 3.0 × 107 (mean 2.5 × 106) per g, Aerobic Plate Counts from 3.0 × lo3 to > 3.0 × 107 (mean 1.8 × 106) per g. No seasonal distribution of V. parahaemolyticus was apparent. No statistically significant relationship existed between V. parahaemolyticus count of oysters and bacteriological (Standard Plate Count, Aerobic Plate Count, coliform, fecal coliform and E. coli counts) and environmental parameters (water temperature, salinity, pH, dissolved O2, sampling depth, tide, wind and rainfall).
EFFECT OF CALIBRATION PROCEDURES ON ACCURACY AND PRECISION OF AUTOMATED KJELDAHL NITROGEN ANALYSIS IN SOME FORMULATED FOODS
Authors: VINCENT K. R. , SHIPE W. F.
Published: August 2006

The Technicon AutoAnalyzer total nitrogen system was studied to determine some of the limitations and special modifications of the method that pertain to the analysis of formulated foods with one or more high protein ingredients. Assorted instant breakfasts and meat analogs were used as test products. Specifically, the effects of composition of calibration standards, heat of continuous digestion, and nitrogen concentration on the agreement between AutoAnalyzer and manual macro‐Kjeldahl were studied. Resistance of particular protein types to continuous digestion did not constitute a major limiting factor in the precision and reproducibility of the automated method, so that fixed temperatures could be used for diverse proteins. Standard deviations from 0.21–0.47% protein were obtained with the AutoAnalyzer for 5–8 replicates of several different food products compared to about 0.22–0.37% for manual Kieldahls. Of more imuortance than qualitative composition of standards was the maintenance of a narrow‐ range of concentration (100 ppm N) for sample solutions and calibration with dual standards corresponding to the lower and upper limits of the concentration range. Better accuracy and reproducibility were achieved with calibration standards prepared from dispersible or soluble ingredients that formed stable, homogeneous acid mixtures. Although the method is not recommended as the best means of obtaining accurate nutritional composition data for formulated foods, the automated method may be used for less demanding applications, including rough proximate analyses.
PARTICULATE PROPERTIES AND RHEOLOGY OF PREGELLED YAM (Dioscorea rotundata) PRODUCTS
Authors: AYERNOR GEORGE S.
Published: August 2006

Yam was processed and roller dried. Processing variables included tissue cooking and comminution conditions. Water related characteristics of these pregelled flours were obtained. Increasing the degree of starch damage changed flour specific surface, crystallinity, monolayer adsorp tion, heat of adsorption, wetting temperature, water‐holding capacity and swelling power of the flour. Rheological properties of doughs were determined by simple compressive and cyclic tests with an Instron Universal Testing Machine. Modulus of elasticity, ultimate deformation, recoverable elasticity and energy loss ratio of the various samples were related to the degree of starch damage.
INSTABILITY OF PATULIN IN CHEDDAR CHEESE
Authors: STOTT W. T. , BULLERMAN L. B.
Published: August 2006

When 50 μg/g patulin was added to Cheddar cheese and stored at 5° and 25°C for varying time periods, the toxin became undetectable by chemical and biological means. Less than 27% of the added toxin was detected after 3 hr and less than 16% after 48 hr. The reaction was not affected by storage temperature or the presence of microorganisms and thus appeared to be chemical in nature. A patulin producing strain of Penicillium patulum grew well on Cheddar cheese at 5° and 25°C, but patulin production was not observèd at 5°C, and only small, variable amounts of patulin were noted at 25°C. The patulin formed at 25°C on the cheese was authentic as shown by UV absorption maxima and high pressure liquid chromatography, and it possessed biological activity against Bacillus megaterium and Clostridium perfringens. Potassium sorbate, vacuum packaging and coating cheese with paraffin wax all pre vented growth of P. patulum on retail size pieces of cheese stored at 5° and 25°C. A heat‐sealed wrapping on large (20 lb) blocks of cheese also prevented growth of this organism on cheese stored at 12°C for 6.5 wk.
A MICROBIOLOGICAL PROFILE OF COMMERCIALLY PREPARED SALADS
Authors: TERRY RALPH C. , OVERCAST W. W.
Published: August 2006

Commercially prepared salads from nine different producers were examined for the number of aerobic, psychrotrophic and coliform organisms, the number of yeast and molds, and pH. Samples were examined twice: once when received and once 5 days following the designated expiration date. Colonies from both sets of plates were selected, based on visual differences, for purification and identification in an attempt to determine what bacteria were present in the salads. Organisms recovered included the genera Bacillus, Lactobacillus, Leuconostoc, Streptococcus, Micrococcus, Staphylococcus, Pseudomonas, Xanthomonas, Escherichia, Citrobacter, Enterobacter and one Actinomyces. The genera found in largest numbers were Bacillus, Lactobacillus, Leuconostoc, and Streptococcus
EFFECT OF SALT, SODIUM TRIPOLYPHOSPHATE AND STORAGE ON RESTRUCTURED PORK
Authors: SCHWARTZ W. C. , MANDIGO R. W.
Published: August 2006

The effect of 20 combinations of salt and sodium tripolyphosphate (STP) on restructured pork were studied. Added salt increased TBA values, packaging loss, improved cooked color, aroma, flavor and eating texture and decreased cooking loss and raw color. Increase in STP decreased cooking loss and increased TBA values, packaging loss, raw color and juiciness. Synergism between salt and STP was shown for most traits studied. Storage increased TBA values, water‐holding capacity and juiciness rating and decreased cooking loss, raw color, cooked color, aroma, flavor and eating texture. Among the 20 combination levels, 0.75% salt and 0.125% STP were the most desirable for producing restructured pork.
INFLUENCE OF MECHANICAL SEPARATION UPON PROXIMATE COMPOSITION, FUNCTIONAL PROPERTIES AND TEXTURAL CHARACTERISTICS OF FROZEN ATLANTIC CROAKER MUSCLE TISSUE
Authors: WEBB N. B. , HARDY E. R. , GIDDINGS G. G. , HOWELL A. J.
Published: August 2006

Mechanically separated (MS) fish muscle tissue was compared with hand‐separated (HS) tissue to determine their relative effects upon functional properties and final product texture. Proximate analyses revealed that HS muscle tissue was significantly higher in moisture content than MS tissue. MS tissue had significantly higher quantities of sarcoplasmic and nonprotein nitrogen than HS tissue. No significant difference was found between the level of myofibrillar protein for the two treatments, as determined by sodium dodecyl sulfate (SDS, 1%) extraction, although the HS tissue had a slightly higher level. A significantly higher amount of myofibrillar protein and a lower amount of stroma protein was extracted by SDS than by NaCl (0.58M) for both treatments. This difference was attributed to the development of an insoluble sol by the NaCl extraction method which was sedimented as a gel by centrifugation. Stroma protein was significantly higher in the HS tissue for both extraction methods. There was no significant difference between the two treatments for emulsifying capacity or cook stability and these were not related to final product texture evaluated by a sensory panel and instrumental shear force. The texture of the comminuted product prepared with HS tissue was significantly better than that prepared with MS fish tissue.
CHEMICAL AND SENSORY ANALYSIS OF ROUNDNOSE GRENADIER (Coryphaenoides rupestris) STORED IN ICE
Authors: BOTTA J. R. , SHAW D. H.
Published: August 2006

Roundnose grenadier (Coryphaenoides rupestris) was stored in ice in order to investigate changes in chemical and sensory characteristics. Analyses indicated that the keeping time of at least 18 days was better than that of most species of whitefish. Total lipid and free fatty acid concentration did not significantly change during iced storage. Inosine monophosphate, inosine, hypoxanthine, iodine number, peroxide value, thiobarbituric acid value, trimethylamine content determined by the Tozawa method, trimethylamine content determined by the Dyer method, moisture content, and pH all significantly (P ≤ 0.05) changed during iced storage. Both peroxide and iodine values appeared to have potential as indicators of sensory quality. Trimethylamine concentrations, determined by both methods, were similar throughout the iced storage study.
CONTINUOUS COAGULATION OF COTTAGE CHEESE WHEY PROTEIN
Authors: PANZER C. C. , SCHOPPET E. F. , SINNAMON H. I. , ACETO N. C.
Published: August 2006

Processes are described for obtaining a low moisture, free‐flowing protein powder of high nutritional value through the high temperature (120°C) heat coagulation of cottage cheese whey protein in a constant stirred reaction vessel using steam injection heating. Dried protein concentrates produced by the suggested alternative processes contain 65%, 85% and 95% protein, respectively. Essentially all the coagulable protein can be removed in 8 min of holding time in a pH range of 5.5–6.5. Increasing coagulation temperature to above that of conventional methods (85–100°C) significantly decreases processing time without adversely affecting product quality. The highly nutritious protein fraction produced has potentially wide application in the protein fortification of foods not requiring the normal functional properties of whey protein.
TEXTURE AND CRYSTALLIZATION CONTROL IN RAISINS
Authors: BOLIN H. R.
Published: August 2006

Upon protracted storage of raisins a crystalline material can develop on their surface, especially at higher moisture levels. A method of controlling this formation was developed, which consisted of subjecting the raisins to a mild heat‐treatment. This heat‐treatment procedure also had a tenderizing effect on raisins, making them noticably softer. Other factors were studied that affected raisin texture during storage with bran‐flakes. Raisin desiccation rate was found to be affected by storage temperature, pressure and coatings. Paraffin coating had the most pronounced effect. Protein coatings of solubilized soy protein or egg albumen followed by heat‐denaturation also significantly reduced moisture loss from raisins stored with bran flakes.
FUNCTIONAL PROPRETIES OF RAPESEED FLOURS, CONCENTRATES AND ISOLATE
Authors: SOSULSKI F. , HUMBERT E. S. , BUI K. , JONES J. D.
Published: August 2006

The functional properties of rapeseed meal, flours, protein concentrates and isolate were evaluated in comparison with those of soybean. Generally, rapeseed products were lower in protein but higher in crude fiber and ash contents than the corresponding soybean flour, concentrate or isolate, Rapeseed flours were comparable to soybean flour in water absorption but showed much higher nitrogen solubility, fat absorption, oil emulsification, whippability and foam stability. The viscoamylograph curves for rapeseed flours were characterized by intermediate peak and high cold viscosities, but their gelation properties were poor. Unfortunately, flour from the low glucosinolate cultivar, Tower, contained 1.2 mg/g of glucosinolates, primarily oxazolidinethione, and only the detoxified concentrates and isolate would be safe for human consumption. Rapeseed concentrates and isolate showed excellent water‐and fat‐holding capacity and the isolate was high in oil emulsification and whipping characteristics. While superior to soybean products in most functional tests, the utilization of rapeseed products may be limited by green or brown colors in the aqueous slurries.
CHANGES IN AMYLOID CARBOHYDRATES DURING PREPARATION OF SWEET POTATO FLAKES
Authors: WALTER WILLIAM M. , PURCELL ALBERT E. , HOOVER MAURICE W.
Published: August 2006

Precooked dehydrated sweet potato flakes were prepared by the enzyme activation technique. After lye peeling and grinding, the puree was held at 75°C for timed intervals, then processed into flakes. Flakes from each time period were analyzed for maltose, dextrin and starch content; for changes in starch and dextrin molecular size; and for changes in rheological properties. It was found that all of these factors changed most rapidly during the first 10 min of conversion and that significant starch hydrolysis occurred during lye peeling. A slow but steady change took place among the macromolecular components for 60 min of conversion time. Our data suggested that the properties of macromolecular components could be used as a guide in the selection of optimum conversion conditions.
CHARACTERIZATION OF CELL BOUND GLUCOSE ISOMERASE OF Streptomyces bikiniensis
Authors: PARK Y. K. , CHISAKI C. , MORETTI R. H.
Published: August 2006

Numerous microorganisms were screened for d‐glucose isomerizing activity from soil by this laboratory. It was found that a strain of Streptomyces bikiniensis produced high activity of glucose isomerase in culture medium containing xylose or xylan as inducer. The cell bound glucose isomerase was prepared using cells of S. bikiniensis. The cell bound enzyme also efficiently catalyzes the isomerization of d‐xylose and d‐ribose and to a lesser extent L‐rhamnose and d‐arabinose to their respective ketoses. Isomerization of glucose to fructose by the enzyme was stimulated most effectively by Mg2+ and CO2+ combined or singly, and slightly by Mn2+. Cobalt and Mg2+ also inhibited thermal denaturation of the enzyme. The optimum pH for the enzyme was between 8 and 9, and optimum temperature was found to be 80°C. The enzyme is highly thermostable. The cell bound glucose isomerase was examined for isomerization of glucose to fructose in a batch system by incubating a mixture of the enzyme and various concentrations of glucose in 0.05M phosphate buffer, pH 7.2 containing 5 mM MgSO4 and 0.5 mM CoCl2 at various temperatures. It was found that maximum isomerization of glucose to fructose (50%) was reached when optimum concentration of enzyme and substrate was incubated at 70°C for 70 hr. The cell bound enzyme can be recovered after the operation and used for successive operations.
HEAT INACTIVATION TEMPERATURE‐TIME RELATIONSHIPS FOR PECTINESTERASE INACTIVATION IN CITRUS JUICES
Authors: EAGERMAN B. A. , ROUSE A. H.
Published: August 2006

The necessary pasteurization temperature, F and z values for pectinesterase inactivation were developed for three varieties of orange juices and one grapefruit juice. Since common commercial practice involves blending various orange varieties, the recommended conditions are those for the most heat resistant variety. For an FT=1.0 min, the recommended processes are T = 194°F with z = 12.2 for orange juice and T = 186°F with z = 9.3 for grapefruit juice.
STRUCTURAL FUNCTIONS AND TASTE IN THE SUGAR SERIES: THE STRUCTURAL BASIS OF BITTERNESS IN SUGAR ANALOGUES
Authors: BIRCH G. G. , LEE C. K.
Published: August 2006

Chemical modification of simple sugars and glycosides almost always results in products which are bitter, sweet, or bitter/sweet, although they are occasionally tasteless. Bitterness in all these molecules appears to be the result of polar as well as lipophilic molecular features. Ring size and shape also play a part in the bitter response. Unlike sweetness which seems primarily to be associated with the third and fourth hydroxyls of glucopyranosyl structures, bitterness is chiefly associated with hydroxyl groups on carbon atoms 1, 2 and 6, and with the ring oxygen atom. The configuration of substituents on carbon atoms 1 and 2 may determine bitterness in many molecules and indeed β‐glycosides and β‐linked oligosaccharides are more likely to be bitter than their α‐linked counterparts. Unlike sweetness, which requires precise molecular dimensions in glucopyranosyl structures, no distinct interorbital distances can yet be established for bitterness. However, AH,B systems may suffice to explain bitterness in some types of sugar analogue.
IDENTIFICATION OF PIGMENTS OF THE EGG YOLK FROM PHILIPPINE‐BRED DUCKS
Authors: RODRIGUEZ D. B. , ARROYO P. T. , BUCOY A. S. , CHICHESTER C. O.
Published: August 2006

Carotenoid composition of the egg yolk of duck (Anus bochas) raised in the Philippines was investigated in order to characterize the pigments responsible for its desirable orange color. Analyses and identification were by column chromatography, thin‐layer chromatography with authentic samples, visible absorption spectroscopy and chemical reactions. Principal pigments identified were β‐carotene and canthaxanthin. Lower levels of echinenone, cryptoxanthin and zeaxanthin were also detected. The data obtained revealed significant differences in the carotenoid pattern of duck and chicken egg yolks. The ketocarotenoids canthaxanthin and echinenone, which apparently account for the typical orange yolk color of ducks raised under Philippine conditions, are not normally found in chicken yolk. Chicken egg yolk has been reported in the literature to contain primarily the hydroxycarotenoids lutein, zeaxanthin and cryptoxanthin. β‐carotene has also been found in chicken yolk but not as a major pigment.
PRESSURE‐INDUCED SOLUBILIZATION OF MYOFIBRILLAR PROTEINS
Authors: MACFARLANE J. J. , McKENZIE I. J.
Published: August 2006

In an earlier study it was found that the application of high pressure to homogenates of meat in saline solution could increase water‐holding capacity and promote the solubilization of proteins. These studies have now been extended to myofibrils prepared from sheep semimembrano‐sus muscle. The amount of protein solubilized by pressurization was found to be dependent on (1) temperature, generally being greater at 0°C than at 30°C; (2) the nature and the concentration of the salt; and (3) the pH. SDS gel electrophoresis indicated that solubilization of all the major constituent proteins of the myofibril could be promoted. It is suggested that the imidazole group is implicated in the pressure solubilization effect.