bluuebunny/crossref_metadata_2025 huggingface dataset:
LEVELS OF CHLORINE AND CHLORINE DIOXIDE OF EQUIVALENT BACTERICIDAL EFFECT IN POULTRY PROCESSING WATER
Authors: LILLARD H. S.
Published: August 2006

Equivalent levels of chlorine and chlorine dioxide (generated on‐site) were established on the basis of bactericidal action in bird chiller water. When introduced directly into the chiller water after processed birds had begun to enter the chiller, 5 ppm CIO2 and 34 ppm CI2 were equally bactericidal. When introduced into the chiller with the fresh‐water input, 20 ppm CI2 and 3 ppm CIO2 were equally effective. The use of about 1/7 as much CIO2 as CI2 would be less corrosive to processing equipment and provide the poultry industry with an alternative bactericide to chlorine.
INHIBITION OF BACTERIA ISOLATED FROM GROUND MEAT BY STREPTOCOCCACEAE AND LACTOBACILLACEAE
Authors: OUBOIS GEORGES , BEAUMIER HELENE , CHARBONNEAU RAYMOND
Published: August 2006

Cultures of the genera Pediococcus, Lactobacillus, Leuconostoc and Streptococcus were tested for their ability to inhibit 103 bacterial isolates from ground beef by a cross‐streaking technique. The bacterial isolates that were inhibited to the greatest extent were Gramnegative and were classified as species of Serratia, Enterobacter and Pseudomonas in decreasing order. Among lactic strains, the genus Streptococcus showed the strongest inhibitory power and the Pediococcus and the Lactobacillus the least strong. The Streptococcus lactis strains, in particular, were the most inhibitory, even though this power may vary from one strain to another in the same species. A nonspecific inhibitory substance seemed to be responsible for this phenomena.
EFFECT OF MATURITY AND MARBLING ON THE MYOFIBRIL FRAGMENTATION INDEX OF BOVINE LONGISSIMUS MUSCLE
Authors: PARRISHJR F. C. , VANDELL C. J. , CULLER R. O.
Published: August 2006

Myofibril fragmentation index (MFI), sarcomere length, total and soluble collagen, Warner‐Bratzler shear and sensory tenderness were determined on loin steaks from carcasses that varied in marbling, maturity and composition. Loin steaks from 72 A, 11 B, 19 C and 22 E maturity beef carcasses were removed at lo‐14 days of postmortem storage at 2°C. Steaks were double wrapped in freezer paper and stored at ‐29°C until the samples were used for analysis. MFI was significantly related to sensory tenderness scores as evidenced by the correlation coefficients of 0.66, 0.77, 0.75 and 0.71 for A, B, C and E maturities, respectively, and 0.76 for all maturities. MFI of loin steaks from A maturity were significantly different from MFI of loin steaks from B, C and E maturity carcasses. Differences in MFI among marbling groups within A maturity were found only at the lowest degree of marbling (practically devoid). There fore, it seems that MFI could be useful as a criterion of quality for A, B, C and E maturity carcasses, and especially A maturity carcasses without being significantly affected by marbling degree or carcass composition. These results further substantiate the use of myofibril fragmentation tenderness as a term to describe a state of tenderness of conventionally aged bovine longissimus muscle.
ACTION OF PROTEOLYTIC ENZYMES ON BOVINE MYOFIBRILS
Authors: ROBBINS FREDERICK M. , WALKER JOHN E. , COHEN SAMUEL H. , CHATTERJEE SUPRABHAT
Published: August 2006

The effect of cathepsin D from muscle and spleen on bovine myofibrils has been examined under postmortem pH conditions using sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis, scanning electron microscopy (SEM) and electron spin resonance spectroscopy (ESR). Cathepsin D causes a degradaticy of 2 disks of the myofibrils and has a relatively selective action on the myofibrillar proteins in comparison to the plant derived enzyme papain. The heavy chain of myosin (200,000 daltons) was degraded to fragments of about 170,000, 150,000, and 80,000 daltons at 25°C. Degradation becomes more extensive at 37°C. ESR studies on spin‐labeled myofibrils indicated that the proteolytic attack of cathepsin D occurred more distal to the globular region of the myosin when compared to papain or trypsin. Although there appears to be little proteolytic effect on D actinin or actin, changes in the gel electrophoresis pattern below 42,000 daltons indicate alterations of the regulatory complex and myosin light chains.
RIPENING CHANGES AND FLAVOR DEVELOPMENT IN MICROBIAL ENZYME TREATED CHEDDAR CHEESE SLURRIES
Authors: SOOD V. K. , KOSIKOWSKI F. V.
Published: August 2006

Cheddar cheese slurries from salted curds were studied to determine an initial level of microbial protease and lipase that potentially might be incorporated optimally into Cheddar cheese to accelerate ripening without developing flavor defects. Soluble protein, free volatile fatty acids values and total bacteria counts of microbial enzyme treated slurries were considerably higher than in controls. Slurry pH decreased slightly during initial ripening but then rose gradually, with the rate of rise, particularly marked in microbial enzyme treated slurries. Electrophoretic illustrations indicated more degradation of ols, and p‐caseins in microbial enzyme treated slurries than in the control slurry. Bitter peptides formed in microbial enzyme treated slurries were transitory. Microbial enzymes used in slurries were inactivated at 80°C.
OCCURRENCE AND DETERMINATION OF N‐NITROSOPROLINE AND N‐NITROSOPYRROLIDINE IN CURED MEAT PRODUCTS
Authors: PENSABENE J. W. , FEINBERG J. I. , PIOTROWSKI E. G. , FIDDLER W.
Published: August 2006

N‐Nitrosopyrrolidine (NPYR) has been detected and confirmed at the ppb level in a significant number of fried bacon samples. N‐Nitrosoproline (NPRO) has been assumed to be the primary precursor of NPYR, but there are conflicting reports about its precise role. A method was developed for determining NPRO and a survey of 60 cured meat samples was conducted. No NPRO was detected in uncooked, conventionally cured bacon, Canadian bacon, ham, salt pork, pork roll or pastrami. NPRO was detected and confirmed in 1 of 7 dry cured bacon samples (106 ppb), 8 of 12 dry cured ham samples (18‐604 ppb), and 5 of 6 samples of pork side meat (86‐411 ppb). The results suggest the NPRO may not be the main precursor of NPYR in bacon, but may have a role in nitrosamine formation in dry‐cured products.
FURTHER STUDIES ON THE ENRICHMENT OF LIME‐TREATED CORN WITH WHOLE SOYBEANS
Authors: BRESSANI R. , BRAHAM J.E. , ELIAS L.G. , RUBIO M.
Published: August 2006

A series of experiments were performed to study further the effect of supplementing corn with whole soybeans processed in a batch home process and in a continuous industrial operation on chemical composition, presence of antiphysiological substances and protein quality of tortillas. Variables studied with the conventional home cooking process included levels of whole soybeans from 0‐20%, cooking times at atmospheric pressure and 96°C from 0‐90 min at a constant corn‐to‐soybean ratio of 85:15 and lime concentration of 0, 1 and 2%. In the industrial process a 90:10 mixture of corn to whole soybeans was used, and processing conditions were those normally employed for corn alone. Although addition of whole soybeans to corn increased total protein and fat content, both the PER and weight data suggest that the optimum amount of soybeans to add to maize falls between 8 and 12%. Levels of soybeans above 12%, did not significantly improve PER any further. Antiphysiological factors were inactivated after 30 min of cooking independent of lime concentration in the home process. These factors were also inactivated in the industrial process as measured chemically and by biological assays. The study demonstrated the feasibility of producing an enriched tortilla flour at the industrial scale, which besides containing a higher protein content and quality, also provides an increased amount of calories to the consumer.
ESTIMATION OF ZINC AND COPPER IN RAW AND COOKED LEGUMES: AN INTERLABORATORY STUDY OF ATOMIC ABSORPTION AND X‐RAY FLUORESCENCE SPECTROSCOPY
Authors: ROCKLAND L. B. , WOLF W. R. , HAHN D. M. , YOUNG R.
Published: August 2006

Zinc and copper are important nutrient elements in dry beans. The precision and accuracy of two instrumental methods, atomic absorption and x‐ray fluorescence spectroscopy, were compared and evaluated for the estimation of total copper and zinc in raw and cooked legume products. After calibration against National Bureau of Standards reference samples, corrected values obtained by both methods were essentially identical and in good agreements with values reported in the literature for random, analogous materials. Cooked standard and quick‐cooking beans both contained nutritionally significant amounts, but less zinc and copper than inedible, raw, dry beans.
TEXTURIZATION OF SUNFLOWER/SOY FLOUR MIXTURES: CHEMICAL AND NUTRITIVE EVALUATION
Authors: YÁÑEZ ENRIQUE , VÁSQUEZ MAGAL Y , SÁNCHEZ FERNANDO
Published: August 2006

The thermoplastic extrusion technique using a Wenger, X‐25 extrusion cooker was applied to mixtures of sunflower flour and soy flour in the ratios 1:1 (TSP1) and 3:1 (TSP2). The processing conditions were as follows: extrusion moisture 18%, feed rate 2750 g/min and extrusion temperature 145°C. Proximate analyses were performed on TSP, and TSP. The amino acid content of sunflower flour and of TSP, were determined in a Perkin‐Elmer amino acid analyzer after acid hydrolysis of the proteins. The protein content of TSP, and TSP, was 46 and 48%, respectively, and both samples were tested for their PER in rats. The values obtained were 1.96 for TSP, and 1.63 for TSP. The casein control diets gave PERs of 2.54 and 2.48, respectively. Supplementation of TSP, with 0.15% DL‐methionine improved its PER to 2.32 (P < 0.05), but 0.30% of the same amino acid failed to produce a further increase in protein efficiency ratio. Supplementation of TSP, with 0.1% L‐lysine improved the PER to 2.09 but this value was not as good as methionine‐ supplemented TSP. Apparent digestibilities shown by these texturized, high protein flour mixtures may be considered satisfactory.
Yersinia enterocolitica: A REVIEW OF THE PSYCHROTROPHIC WATER AND FOODBORNE PATHOGEN
Authors: STERN N. J. , PIERSON M. D.
Published: August 2006

Infection in humans may be caused by Yersinia enterocolitica. Several foodborne outbreaks implicating this microorganism have been documented. Y. enterocolitica was shown to be the causitive agent of a foodborne disease outbreak in school children in upstate New York. Gastroenteritis and pseudoappendicitis were the predominant symptoms in this outbreak. It is hypothesized that the organism may be transmitted directly or indirectly to foods and water through fecal contamination or by the urine of a carrier animal. Swine have been shown to be the species most consistently harboring serotypes of Y. enterocolitica implicated in enteritis. The etiology of Y. enterocolitica diseases and infection and the most current isolation methodology is also reviewed. The distinguishing characteristics of this microorganism are its psychrotrophic growth capabilities, motility at 25°C, nonmotility at 37°C negative phenylalanine deaminase, and positive urease activity. Controversy exists regarding classification of‘the species: whether the species belongs within the genus Yersinia and if the species should be further subdivided according to invasiveness and other biochemical distinctions are considered in this review.
DIETARY CAFFEINE, GLUCOSE TOLERANCE AND INSULIN SENSITIVITY IN MICE
Authors: ARAUJO P. E. , MAYER J.
Published: August 2006

Mice consumed diets which contained caffeine and predominated in either corn starch, sucrose or hydrogenated vegetable oil. When compared by means of an oral glucose tolerance test to mice which had eaten the same diets without caffeine, it was found that they had a more rapid return of blood glucose to resting values. In vivo measurements of glucose uptake by diaphragm and epididymal fat pad revealed differences in this adaptation to caffeine. The adaptive mechanism appeared to vary with type of diet. When mice were given caffeine chronically in their drinking water there was evidence of adaptation occurring in the ability of muscle to increase glycogen stores in the presence of caffeine in vitro. No differences were found in other tissue glycogen levels.
PALATABILITY OF PRERIGOR AND MECHANICALLY PROCESSED NITRITE‐FREE HAMS
Authors: JUDGE M. D. , CIOCH J. J.
Published: August 2006

The effects of mechanical treatment (massaging) and prerigor infusion of a nitrite‐free salt solution on the palatability of nonheat‐processed hams were determined. Massaging in the prerigor state after salt infusion resulted in reduced thiobarbituric acid (TBA) reaction values in muscle tissue at the end of a 14‐day storage period at 3°C as compared to salt infusion alone either pre‐ or postrigor. Extended frozen storage (13 wk at ‐40°C) resulted in TBA values in adipose tissue in all treatment groups of a magnitude normally associated with rancid flavors. A meat tenderizing action by the massaging treatment was noted from Warner‐Bratzler shear tests performed on several muscles of dry roasted hams. Taste panel data also identified massaging treatment effects on tenderness but not on juiciness or flavor. The taste tests established that all treatment combinations produced nitrite‐free hams that were generally acceptable in most sensory attributes. Panel members associated the flavor and texture with that of uncured roasted pork.
pH AND BUFFERING CAPACITY OF CANNED GREEN PEPPERCORNS
Authors: POWERS JOHN J. , SHINHOLSER KATHLEEN
Published: August 2006

The pH, total acidity, and buffering capacity of canned green pep percorns against increases and decreases in pH were determined. The mean pH of nonacidified, canned green peppercorns was 6.51. The total acidity was 0.048%, calculated as citric acid. The buffering capacity between the original pH of the peppercorns and pH 8.35 was 0.188 milliequivalents. To lower the pH to 4.4, from 219‐247 mg citric acid per 100g till‐in weight of peppercorns is required. Canned green peppercorns acidified to pH 4.0 retained much of the pungency and pepperiness of fresh green peppercorns.
COMPUTER MALFUNCTION CAUSES EXTENSIVE ERRATA IN CAPSICUM DATA
Authors: NAGLE B. J. , VILLALON B. , BURNS E. E.
Published: August 2006

A NUMBER OF ERRORS occurred in the paper Color Evaluation of Selected Capsicums by B.J. Nagle, B. Villalon, and E.E. Burns [J. Food Sci. 44(2): 416‐418] as a result of computer failure while performing the calculations. Since all the errors occurred in the Results & Discussion, this section of the paper is being reprinted in its entirety with all necessary corrections included.

These errata clearly demonstrate that computers (calculators) are not infallible, and point up the necessity for making periodic checks with standard calculations with verified results.
CORRELATION OF OFF‐ODOR SCORES OF CANNED TUNA WITH GAS CHROMATOGRAPHIC DATA
Authors: KHAYAT ALI
Published: August 2006

Presently, several chemical tests are used to determine the quality of canned tuna. The need for developing a single test motivated this research, Profiles of canned tuna volatiles were obtained using high resolution gas chromatography. A high correlation between the volatile profile and sensory panel scores was obtained. Two models based on three or five major peaks were developed for predicting quality scores. Using such models, correlation coefficients of 0.90 and 0.91 have been obtained. The error associated with predicted sensory scores using such models was in the order of to.5 unit. Such error has the same magnitude as the inherent error associated with taste panel itself.
GROWTH AND CONTROL OF HALOPHILIC MICROORGANISMS IN SALT MINCED FISH
Authors: VARGA S. , SIMS G. G. , MICHALIK P. , REGIER L. W.
Published: August 2006

The apparently good shelf stability of salt minced fish produced by the quick salting technique is due to the very low halophilic bacteria content. The nature of the quick salting method and the quality of the curing salt used are responsible for this condition. With no loss in palatability the salted minced fish was rendered stable at 35°C either by reducing water activity to 0.7 or by adding 0.3% sorbic acid into the minced flesh with the curing salt. A sorbic acid residue in the desalted product of 0.1% was less than the limit allowed in some food products.
CHANGES PRODUCED IN MUSCLE PROTEINS DURING INCUBATION OF MUSCLE HOMOGENATES
Authors: YAMAMOTO KATSUHIRO , SAMEJIMA KUNIHIKO , YASUI TSUTOMLJ
Published: August 2006

Under some experimental conditions, considered analogous to those which may exist in postmortem muscle, changes in the extractability of sarcoplasmic proteins and the composition of myofibrillar and sarcoplasmic proteins were examined. During incubation at neutral pH, degradation of myofibrillar proteins hardly occurred in the absence of Ca++, but or‐actinin was released and troponin components were degraded in its presence. Myosin was degraded at acidic pH value regardless of the presence or absence of Ca++, which no such effect was observed at the neutral pH value. From these results, the degradation pattern of myofibrillar proteins can be classified as of two types: (1), the degradation of regulatory proteins which is Ca++‐dependent; and (2), that at acidic pH which preferentially includes the degradation of myosin heavy chain. Phosphorylase, which occurs in the sarcoplasm, appears to have an affinity for myofibrils which depends on pH and temperature.
VINYLCHLORIDE SORPTION BY DRY CASEIN PARTICLES: MECHANISTIC CONSIDERATIONS
Authors: BIRAN O. , GIACIN J. R. , HAYAKAWA K. , GILBERT S. G.
Published: August 2006

Sorption of vinylchloride (VCM) by dry casein particles was determined as a function of temperature and moisture content. The amount sorbed was found to increase with a decrease in temperature or reduction in moisture content of the particles. At 30° C, the partition coefficient values (Ku) were 1.05, 0.4 and 0.33 × 102 for casein particles of moisture content 3.5, 6.0 and 7.5, weight percent respectively. The partition coefficient was defined as the equilibrium concentration of VCM sorbed over the sorbate concentration in the headspace. The effect of dipole moment of the sorbate on sorption to casein was evaluated by comparing sorption of VCM and the analogues, ethylene and vinylidene chloride. Sorption was found to increase with the dipole moment of the sorbate, suggesting the importance of dipole moment as a sorption inducing factor. Further supportive evidence for the importance of dipole moment in sorbate‐casein interaction was obtained by a gas chromatographic technique (inverse phase gas chromatography). Using casein as the stationary phase of a gas chromatographic column, the solutes VCM, ethylene, vinylidene chloride (VCD) and hexane were pulsed through the column and the peak shapes recorded. Peak shapes indicated an interaction between casein and the polar solutes (VCM and VDC) whereas no such interaction (sorption) was indicated for the nonpolar solutes, ethylene and hexane. A rate model for VCM sorption by dry casein particles was also developed.
ANTHOCYANINS AS FOOD COLORANTS: EFFECT OF pH ON THE FORMATION OF ANTHOCYANIN‐RUTIN COMPLEXES
Authors: WILLIAMS M. , HRAZDINA G.
Published: August 2006

Complex formation of anthocyanins with rutin stabilize their color under conditions similar to those of grape juices. This color intensification results in both the increase in intensity and a batho‐chromic shift in the color of their solutions. The changes in the color intensity of the anthocyanin solutions are not uniform throughout the pH range 1–7, but are influenced by the substitution patterns of the B‐ring, and by the nature of substituent in the 3‐ and 5‐position. Thus maximum complex formation occurs with the 3‐glucosides at around pH 4.2, with the 3,5‐diglucoside at around pH 3.1, with the 3‐acylglucosides around pH 4.0–4.5 and at around pH 3.1 with the 3‐acylglucoside+glucosides: The obtained data further support the involvement of the anhydro base of anthocyanins in the complex formation with rutin in the pH range 1–7.
BETANINE STABILITY IN BUFFERED SOLUTIONS CONTAINING ORGANIC ACIDS, METAL CATIONS, ANTIOXIDANTS, OR SEQUESTRANTS
Authors: PASCH J. H. , von ELBE J. H.
Published: August 2006

The rate of betanine degradation as affected by monocarboxylic acids (lactic acid, acetic acid), metal cations (Fe+++, Cu++), antioxidants (ascorbic acid, α‐tocopherol) and sequestrants (citric acid, Na2 EDTA) was studied. Betanine was extracted from beets using water, and purified by molecular exclusion and adsorption chromatography. Column packings used were Sephadex G‐25, polyacrylamide, and polyvinylpolypyrrolidone. The effect of food additives on the rate of oxidation of betanine in buffered systems was determined using a modification of the active oxygen method. A betanine solution was placed in a reaction chamber, held at 75° C, and oxygen was passed through the solution at a rate of 3 ml/min. The half‐life value of betanine at 75° C, pH 5.0 in a phosphate buffer was 48.0 ± 1.0 min (control). Addition of 100 ppm lactic acid had no effect on stability (41 ± 1.7 mm), while 5.9% acetic acid caused a decrease in stability (33.4 ± 1.9 min) possibly as a result of pH changes at elevated temperatures. Metal ions at a level of 100 ppm caused an increase in the degradation rate compared to that of the control with addition of iron resulting in a half‐life value of 33 ± 1.4 min. Copper had the greatest effect, reducing the half‐life value to 6.0 ± 0.2 mm. Neither 100 ppm ascorbic acid nor 100 ppm a‐tocopherol affected the half‐life value of betanine (45.3 ± 2.3 and 50.2 ± 3.4 min, respectively). Ascorbic acid at 1000 ppm decreased the halt‐life value (32.3 ± 3.3 min), whereas 10,000 ppm citric acid and 10,000 ppm EDTA caused an increase in the half‐life value of 1.5 times compared to that of the control (69.4 ± 3.1 and 70.7 ± 7.1 min). Both 100 and 1000 ppm citric acid had no effect on betanine stability.
BLANCHING EFFECT ON POLYPHENOL OXIDASE ACTIVITY IN TABLE BEETS
Authors: LEE C. Y. , SMITH N. L.
Published: August 2006

Table beet polyphenol oxidase (PPO) causes undesirable color in underblanched products. The effects of pH and temperature on PPO activity were studied. Varietal differences and the effects of blanching on PPO activity of table beets were measured. The enzyme was most active at pH 7.0 and temperature 25°C. The rate of heat inactivation increases rapidly with increasing temperature and follows pseudo‐first order kinetics. The enzyme activity varied among different cultivars of table beets. Water blanching deactivated the enzyme but the time required for a complete inactivation varied according to the size of table beets.
BACTERIAL REPRESSIVE ACTION OF MEAT STARTER CULTURE IN PASTEURIZED LIQUID WHOLE EGG
Authors: RACCACH M. , BAKER R. C.
Published: August 2006

Pediococcus cerevisiae inoculated in pasteurized liquid whole egg (PLWE) (3°C, pH 7.4) had a larger repressive action than Lactobacillus plantarum toward Pseudomonas fluorescens (2.8 and 1.6 log cycles respectively) but both had the same repressive action against1 Pseudomonas fragi and Pseudomonas putrefaciens. The 50:50 mixture of the starter cultures had a repressive action similar to the, pediococci against P. fluorescens but was more effective against P. putrefuciens than against P fragi (2.5 and 1.6 log cycles respectively). At pH 6.8 both starter cultures and their mixture had a, larger repressive action toward the three species of Pseudomonas. Salmonella typhimurium at 11°C, pH 7.4 was not repressed by the starter cultures. At pH 6.8 the repressive action of only the pediococci and the mixture increased (1.0–2.0 log cycles). A further decrease of the pH of the PLWE to 6.2 did not change the repressive action of the starter cultures against the pathogen.
PROTEIN DISPERSIBILITY AND EMULSION CHARACTERISTICS OF FOUR SOY PRODUCTS
Authors: VOLKERT MARY ALICE , KLEIN BARBARA P.
Published: August 2006

The relationship between protein dispersibility (PDI) and certain emulsion characteristics of four soy products: an isolate, two concentrates (toasted and untoasted) and full‐fat flakes, were examined at 5 pH's. PDI, emulsifying activity and emulsion stability were significantly affected by pH. Values for these parameters were lowest at pH 4.5, and increased at pH's above and below this point. Coefficients of determination indicated that pH is a major factor in determining the ability of a soy product to form an emulsion. A strong positive linear correlation between PDI and emulsifying activity and stability was found. The emulsification capacities of the isolate and untoasted concentrate were not affected by pH when the amount of dispersible protein was equalized.
DISINTEGRATION OF CELL WALL AND EXTRACTION OF PROTEIN FROM CANDIDA LIPOLYTICA
Authors: TSANG SHEKKWAN , LEE CHERL‐HO , RHA CHO KYUN
Published: August 2006

The differences between extraction of protein from fresh and from spray‐dried hydrocarbon‐grown yeast (Candida lipolytica) were investigated, and the effect of different protein extraction methods on protein yield was determined. The mechanisms and efficiency of the different methods of cell disintegration and protein extraction are illustrated by scanning electron microscopy. Autolysis of fresh yeast and acid treatment of dried yeast indiscriminately hydrolyzed whole cells and resulted in low yields of extracted protein. Homogenization of alkali‐treated cell suspensions of both fresh and spray‐dried yeast gave maximum yields of extracted protein. The effect of alkali treatment is due to weakening of the cell wall structure and removal of the hydrophobic barrier around it; for dried yeast, alkali treatment has the additional effect of protein solubilization.
PRODUCTION AND CHARACTERIZATION OF β‐GALACTOSIDASE FROM ASPERGILLUS ORYZAE
Authors: PARK Y. K. , De SANTI M.S.S. , PASTORE G. M.
Published: August 2006

A strain of Aspergillus oryzae producing extracellular β‐galactosidase that hydrolyzes lactose in whey and dairy products was selected. The crude lactase concentrates were prepared by both semisolid and submerged fermentation. Yields of the enzyme from semisolid fermentation were much higher than submerged fermentation. The crude enzyme hydrolyzed lactose efficiently in acid whey and 83% lactose hydrolysis was obtained at 55°C. However, the activity of the crude enzyme is greatly reduced in cow's milk. A. oryzae lactase was purified by ammonium sulfate fractionation, chromatography on DEAE‐cellulose, chromatography on CM‐cellulose, and DEAE‐Sephadex A‐50 column chromatography. The purified enzyme had an optimum pH of 5. The optimum temperature was 5°C, whereas, for the crude enzyme preparation, it was 55°C. The pH stability of the enzyme was between 3.5 and 8.0 at room temperature for overnight. The Michaelis constant is 0.77 mM for o‐nitrophenyl‐p‐D‐galactopyranoside (ONPG) and 50 mM for lactose. The values of Vmax are 55.6 μg/min/mg of protein for ONPG and 2.4 μg/min/mg for lactose. Metal ions in the range 0.01‐l mM and sulfhydryl reagent (0.01–0.1 mM of p‐chloromercuribenzoate) have no effect on the enzyme activity. Galactose inhibited competitively the enzyme activity, whereas glucose did not.
VACUUM AGING, DISPLAY AND LEVEL OF NUTRITION EFFECTS ON BEEF QUALITY
Authors: GUTOWSKI G.H. , HUNT M.C. , KASTNER C.L. , KROPF D.H. , ALLEN D.M.
Published: August 2006

Vacuum aging and display effects on various quality traits of beef produced from 38 cattle on four nutritional regimes (grass‐, short‐, long‐, and forage‐fed) were studied. Anterior halves of the longissimus, biceps femoris, semitendinosus, and semimembranosus muscles were fabricated into steaks at 48 hr postmortem; the posterior halves were vacuum aged for 21 days at 0—1°C before fabrication. Taste panel, shear force and cooking analyses were done on steaks from each muscle half before and after 5 days of display under continuous lighting at 1,076 lumens/m2 (100 ft‐c) of deluxe warm white fluorescent light. Vacuum‐ aging improved (P < 0.05) taste panel tenderness, juiciness and flavor, scores; reduced Warner‐Bratzler shear values and increased total and volatile cooking losses for averages of muscles and feeding regimes. Taste panel flavor scores were lower and drip and total cooking losses were reduced (P < 0.05) after vacuum‐aged cuts had been displayed for 5 days. Shear force values continued to decline (P < 0.05) during display. Initial taste panel tenderness and flavor scores were less desirable for steaks from grass‐ and short‐fed cattle. Vacuum aging improved (P < 0.05) tenderness, juiciness, and flavor scores in steaks from grass‐ and short‐fed cattle, but flavor scores were less desirable in these steaks after 5 days of display. Shear force values were lowest (P < 0.05) in steaks from long‐fed cattle. Total cooking and drip losses generally were lowest (P < 0.05) in steaks from grass‐fed cattle. Vacuum aging increased (P < 0.05) total cooking loss in all steaks except those from the short‐fed regime but reduced the variation in total cooking loss across all nutritional regimes.
LIPID OXIDATION IN BOLOGNA CONTAINING MECHANICALLY DEBONED BEEF
Authors: MISOCK J.P. , KUNSMAN J.E. , FIELD R.A.
Published: August 2006

Control bologna and bologna in which 20% of the lean beef was replaced with mechanically deboned meat (MDM) were manufactured. Bologna was evaluated for palatability characteristics and monitored for decreases in the fatty acids of the polar and nonpolar lipid fractions and for the production of monocarbonyls. The addition of MDM to bologna had no effect on fatty acid loss during storage and the production of monocarbonyls in MDM‐containing bologna was similar to that of the control bologna. Control bologna and bologna with MDM included had similar flavor scores during storage at 1°C. Both control and MDM bologna showed a slight decrease in flavor scores with increases in storage up to 60 days.
BACTERIAL COUNTS ON SURFACES OF CARCASSES AND IN GROUND BEEF FROM CARCASSES SPRAYED OR NOT SPRAYED WITH HYPOCHLOROUS ACID
Authors: JOHNSON M. G. , TITUS T. C. , McCASKILL LINDA H. , ACTON J. C.
Published: August 2006

Bacterial counts were compared for samples from three groups of beef from two different sources. Group 1 samples were from choice forequarters as received, then sprayed with HOC1 (200 mg/L, pH 6.0–6.5, 7.03 kg/cm2, 12 set at 16°C). Group 2 samples served as controls and were from choice forequarters from the same lot as group 1 but not sprayed. Group 3 samples were from frozen boneless lean domestic and imported beef, Surface strip and ground beef samples from groups 1 and 2 had aerobic plate counts (APC) and lactic acid bacteria counts (LABC) that were not significantly different, P < 0.001. Conversely, strip and ground beef samples from group 3 had APC and LABC that were significantly higher, P > 0.001, than those for the control, group 2, samples. Also, the coli‐form and coagulase positive S. aureus counts were also significantly higher for the group 3 ground beef samples. Thus, the hypochlorous acid spray treatment of beef forequarters did not appear to yield ground beef with better bacteriological quality than the unsprayed forequarters from the same source, perhaps because the initial bacterial count was already so low. The higher surface APC of the lean boneless beef, group 3, was reflected in the higher initial APC of the ground beef prepared from that source.
EFFECT OF PHOSPHATES ON THE PHYSICOCHEMICAL CHARACTERISTICS OF FREEZE‐DRIED SHRIMP
Authors: SHARMA S.C. , SELTZER E.
Published: August 2006

Effects of different phosphates were investigated on the mechanical and storage stability (in dry state), texture, flavor and rehydration characteristics of freeze‐dried shrimp. Kena, SHMP and STPP in powder and slurry form were used to treat raw peeled, deveined shrimp. Coating the shrimp with Kena powder for about 10 min, rinsing and cooking in 2% salt water at 75°C before freeze drying, which resulted in a retention of 0.25% (w.b) of Kena within the tissue, imparted to the product the most desirable mechanical, rehydration and sensory characteristics. The improvements imparted by the Kena treatment to the freeze‐dried shrimp in terms of mechanical stability and shelf life, and to their texture, flavor and overall sensory acceptance were attributed to the reduction in cooking losses and changes in the protein structure of the product.
CUCUMBER QUALITY ‐ A REVIEW
Authors: ENNIS DANIEL M. , O'SULLIVAN J.
Published: August 2006

Significant progress has been made in recent years in assessing and controlling cucumber quality. Studies on fresh cucumbers before and after harvest have provided a basis for an understanding of the compositional changes occurring in the ripening fruit and during storage as fresh or fresh pack cucumbers. The effect of cultural practices and mechanical harvesting on compositional and textural parameters has been investigated, while detailed studies on the instrumental analysis of cucumber textural components has been completed. Studies on the control of bloating in brined cucumbers represents a very exciting and productive area of current interest. The analysis of the flavor component of cucumbers and their biogenesis has received considerable attention and future work on this topic may focus on factors influencing the levels of flavor precursors such as fatty acids.
EFFECT OF MATURITY ON THE NUTRIENT CONTENT AND THE CANNING QUALITY OF EMERALD SOYBEAN
Authors: ISLAM MIR N. , LEA ROBERTA A.
Published: August 2006

Nutrient content and the canning quality of a newly developed green‐seeded soybean, Emerald, were evaluated at 86, 90, 95, 100 and 105 days after planting. Nutrient analyses involving moisture, protein, fat, fiber, minerals, ascorbic acid and carotenes indicated that Emerald soybeans were superior or equal to lima beans and green peas. Canned soybeans were evaluated by a sensory panel using a rank order method. Based on the data on sensory evaluation and nutrient content, the soybeans of 95‐day maturity were found to be most desirable.
EFFICIENCY STUDIES OF A CONTINUOUS DIFFUSION APPARATUS FOR THE RECOVERY OF BETALAINES FROM THE RED TABLE BEET
Authors: WILEY ROBERT C. , LEE YA‐NIEN , SALADINI JOSEPH J. , WYSS ROBERT C. , TOPALIAN HARRY H.
Published: August 2006

The stability of betalaines in beet tissue at 25°C and at simulated diffuser temperatures of 75°, 85° and 90°C under nitrogen and atmospheric conditions in combination with water and various levels of citric acid solutions was investigated. The major objectives of the model system studies were to inactivate endogenous oxidases which are firmly bound to the subcellular structure of the beet tissue and which may catalyze decoloration of the betalaines and to study betalaine stability during these treatments. Operations of the continuous counter‐current diffusion apparatus to recover betalaines from thinly sliced beets showed that an initial fill temperature of 85° C followed by a lower temperature (75° C) and a juice pH of 5.2 were best conditions if extraction of both red and yellow colorants were required. To optimize recovery of betacyanines, a slightly more acid pH of 4.8 was preferred. A 90% recovery of betacyanines under these conditions compared with a 71% recovery of betacyanines in previous work performed at 70–74°C at DH 5.5. Highest betaxanthine recovery of 80% was found at a juice pH of 6.0 and an initial fill temperature of 85° C. Higher initial extraction temperatures and proper acidification by the solvent tended to eliminate the need of N2 for satisfactory recovery of the betalaines.
LIPID CONSTITUENTS OF BLACK WALNUT KERNELS
Authors: SENTER S. D. , HORVAT R. J.
Published: August 2006

Lipids from the kernels of black walnuts (Juglans nigra L.) were quantitated and identified by thin‐layer chromatography and gas‐liquid chromatography‐mass spectrometry. Four classes of lipids were prominent in the walnut oils and were identified as complex lipids, α, β‐diglycerides, sterols, and triglycerides. Triglycerides were the predominant class and comprised 99.9% of the lipids. Twenty‐one fatty acids were isolated and identified. Among these, unsaturated fatty acids were predominant and comprised ca 92% of the fatty acids. On the basis of total fatty acids, octadecenoic and octadecadienoic acids comprised 86.1%. Twelve acids were present in trace amounts and accounted for ca 0.06% of the total.
BAKING PROPERTIES OF PLASMA PROTEIN ISOLATE
Authors: KHAN MIR N. , ROONEY L. W. , DILL C. W.
Published: August 2006

0, 2, 4, 6, 8 and 10% of commercial bread flour (14.3% protein on a d.w.b.) were replaced with bovine plasma protein isolate (96% protein on a d.w.b.) in a short‐time dough bread making system. Loaf volume of the bread made with 2–6% PPI, was significantly higher than the control bread (100% wheat flour). Increasing levels of PPI darkened the crust and crumb colors and made the texture coarse and open. 2% of PPI produced bread with acceptable flavor and could increase the bread protein and lysine by 15% and 75% respectively compared to the control bread. 0, 10, 20 and 30% of commercial egg white solids were replaced with PPI in an angel food cake formula. Increasing levels of PPI lowered the foaming capacity, increased the specific gravity of the foam and decreased the volume of angel food cake. However, 30% PPI (70% egg whites) produced angel food cakes with acceptable flavor which were preferred to cakes containing 100% egg white. The foaming properties of PPI were affected by slight variations in its processing conditions because with certain batches of PPI, substitution levels of more than 30% gave acceptable angel food cakes. The functionality of PPI might be improved by more precise processing conditions.
ADVENTITIOUS MINERAL ELEMENTS IN HOPI INDIAN DIETS
Authors: KUHNLEIN HARRIET V. , CALLOWAY D.H.
Published: August 2006

Both strontium and lead are geologically present in the Hopi area, but only strontium accumulates in culturally important food plants in the agicultural setting. Lead from natural sources is present in traditional ceramics and culinary ash. In native maize corn foods, iron content was elevated several‐fold during home processing. The nutritional environment contains unconventional sources of iron, zinc, manganese and other essential elements.
KINETICS OF AVAILABLE LYSINE LOSSES IN A SOY PROTEIN ISOLATE: CONFIRMATION OF THE ‘TRANSITION PHASE’ BY PROTEIN EFFICIENCY RATIO TESTS
Authors: WOLF J. c. , THOMPSON D. R. , Ahn P. C. , HEGARTY P. V. J.
Published: August 2006

Available lysine losses in soy protein isolates during thermal processing go through three phases: a fist‐order loss, a transition phase and a no‐loss phase. The transition phase shows a statistically significant (P < 0.02) increase in available lysine when measured by the fluoro‐dinitrobenzene (FDNB) method. Using the protein efficiency ratio method (PER), a statistically significant (P < 0.1) increase in available lysine was demonstrated in samples processed at 80° C for 700 mm. The PER values decreased from 2.65 ± 0.04 to 1.17 ± 0.04 after 600 min of processing. At 700 min the PER value increased to 1.37 ± 0.05. At 80°C the transition phase in systems containing 4% sugar occurs 600 mm after processing is initiated according to previously published equations. The PER and FDNB results exhibited an excellent correlation (r = 0.98). Thus, PER results confirm the increase detected using the FDNB procedure.
INFLUENCE OF PRESSURIZATION ON BINDING STRENGTH OF TURKEY MEAT ROLLS STUFFED IN MEMBRANE CASINGS
Authors: MEYDAV SHAUL , TOLEDO ROMEO T. , CARPENTER JOHN A.
Published: August 2006

The influence of pressurization on binding strength between meat pieces stuffed into membrane casings was evaluated using a pneumatic pressurization device. This device simulated the action of a pneumatic machine that is commercially available and is now used by the industry. The contents of a stuffed casing were pressurized when the open end was twisted and inserted through a 1 cm diameter opening on a fixed aluminum ring and pulled by an air cylinder piston to which the casing was attached. Using theoretical considerations, an equation was derived for determining internal pressure in a stuffed roll based on the principle that the pressure developed is a function of the unit strain on the casing. This principle was verified experimentally by monitoring internal pressures in a casing filled with a viscous fluid and connected to a mercury manometer. The internal pressure was linear in a plot against the reciprocal of the outside diameter of the roll The regression equation was used to calculate internal pressures in a casing stuffed with meat from the measured outside diameter. Interfacial binding evaluated as failure force in uniaxial tension decreased slightly with increasing pressures in the roll in excess of 5.7 psig. The decrease was insignificant in rolls ma from frozen meat but was significant in rolls made from fresh meat. In unpressurized rolls, increased incidence of pockets filled with cookout fluid was observed. Pressurization to 2–5 psig internal pressure appears to be optimal in terms of elimination of pockets filled with cookout fluid and maximum interfacial binding between meat pieces.
USE OF PROTEIN DYE‐BINDING VALUES AS INDICATORS OF THE “CHEMICAL AGE” OF CONVENTIONALLY MADE CHEDDAR CHEESE AND HYDROLYZED‐LACTOSE CHEDDAR CHEESE
Authors: KROGER MANFRED , WEAVER JOHN C.
Published: August 2006

A dye‐binding method using amido black dye was developed for determining the “chemical age” of Cheddar cheese. Samples of cheese from two manufacturing processes were analyzed during 8 months of ripening: conventional cheese manufacture and a hydro‐lyzed‐lactose process that results in a more rapidly ripening cheese. Free amino acid analyses were also made and those data compared with dye‐binding values (DBVs). The DBVs correlated to the free amino acid values by 0.85 and 0.84 in the conventional and hydro‐lyzed‐lactose processes, respectively. A quadratic model was established between the DBVs and the free amino acid data. In the different cheese samples analyzed this resulted in a multiple correlation coefficient of 0.82 for the following regression equation: μg = 1374–130.4 (DBV) + 2.83 (DBV)2. The standard error of estimate of this method was 2.4 mg/g of cheese.
MORPHOLOGY OF BACON AND ITS POSSIBLE ROLE IN FORMATION OF NITROSAMINES
Authors: CASSENS R. G. , ITO T. , LEE M.
Published: August 2006

Bacon is composed, morphologically, of regions of either skeletal muscle or lipid filled cells known as adipocytes. Connective tissue is pervasive throughout forming a framework within which the individual cells are held Adipocytes are characterized by having a typical mammalian cell wall which encloses a single large lipid globule; a thin layer of cytoplasmic protein, which contains cell organelles, is interposed between the cell wall and the lipid globule. The possibility that the interface between the lipid globule and the cytoplasmic and connective tissue proteins presents a unique site for reaction with nitrite is discussed.
ULTRASTRUCTURAL POSTMORTEM CHANGES IN ELECTRICALLY STIMULATED BOVINE MUSCLE
Authors: WILL P. A. , OWNBY C. L. , HENRICKSON R. L.
Published: August 2006

Alterations in the morphology of beef longissimus dorsi, psoas major, semitendinosus, and supraspinatus muscles induced by electrical stimulation were studied at the light and electron microscopic levels. Samples of control and electrically stimulated muscles were removed from the carcass at 0.5‐, l‐, 6‐, and 24‐hr postmortem, processed, and embedded in plastic. Changes induced by electrical stimulation were compared with those in normal autolysis in control muscle. Light microscopic examination revealed contraction bands and intracellular edema in the stimulated muscle samples while the control showed no sign of morphological change. At the electron microscopic level, electrical stimulation caused specific structural changes in the muscles. Swollen sarcoplasmic reticulum, mitochondria, and T‐tubules were observed in the stimulated muscle samples. In addition, contraction banding, intracellular edema, disintegration of the myofibril, and other morphological deviations were also observed. These data are in agreement with published work that mechanisms other than the prevention of cold shortening bring about tenderization of the resultant meat. This was partially explained by the accelerated autolysis seen in stimulated striated muscles and was an active rather than passive effect as proposed by cold shortening alone.
USE OF CALCIUM SALTS FOR SOYBEAN CURD PREPARATION
Authors: LU J. Y. , CARTER ELOISE , CHUNG R. A.
Published: August 2006

One of the delicate steps in the preparation of soybean curd is the addition of a salt to precipitate soy protein. The commonly employed salt is calcium sulfate. In this study, the use of other calcium salts (calcium chloride, calcium lactate, calcium acetate, calcium carbonate, calcium phosphate, calcium hydroxide, calcium gluconate) and two noncalcium compounds (glucono‐δ‐lactone and acetic acid) was investigated. The result showed that soy protein was precipitated by calcium chloride, calcium lactate, calcium acetate, calcium gluconate, glucono‐δ‐lactone, and acetic acid. The amount of chemical added to precipitate soy protein varied depending upon the type of compound used, but in all cases, soy protein was precipitated when the pH of soy milk was at or near 6.0. Calcium acetate and calcium chloride appeared to be good precipitants for soybean curd preparation. The quality and sensory score of the soybean curd prepared from these salts requires less skill than calcium sulfate because of solubility; besides, the amount of the salt needed to precipitate soy protein was less than one‐half that of calcium sulfate.
CONVERTING AN F‐VALUE DETERMINED ON THE BASIS OF ONE z‐VALUE TO AN F‐VALUE DETERMINED ON THE BASIS OF A SECOND z‐VALUE
Authors: PFLUG IRVING J. , CHRISTENSEN RONALD
Published: August 2006

A procedure is presented for converting a heat sterilization process F‐value determined on the basis of one z‐value (Z1,) to an F‐value determined on the basis of a second z‐value (Z2). The basis of the conversion is explained. Equations and tabular data for determining the several conversion factors are presented. Examples of the calculation of a new F‐value when there is a change in z‐value are presented.
RADIOMETRIC DETERMINATION AND CHICK BIOASSAY OF FOLACIN IN FORTIFIED AND UNFORTIFIED FROZEN FOODS
Authors: GRAHAM DONALD C. , ROE DAPHNE A. , OSTERTAG SUSAN G.
Published: August 2006

A radiometric assay for food folacin based on the competitive protein binding procedure was developed. The method is rapid, reliable and comparable to the microbiological assay. Cooking and storage did not significantly affect the folacin content of frozen fortified or unfortified frozen dinners and pies. Food folacin availability was measured by chick bioassay. The procedure involves feeding semi‐purified diets containing various levels of folic acid and/or cooked or uncooked frozen convenience foods and measuring plasma and RBC folacin. Levels were directly related to folic acid intake from semipurified diets. Availability of folacin acid added to TV dinners and pies was demonstrated by elevation of plasma and RBC folacin, but fortification of vegetables did not cause consistent elevation.
NITROGEN ASSIMILATION BY Salmonella typhimurium IN A CHEMICALLY DEFINED MINIMAL MEDIUM CONTAINING NITRATE, NITRITE, OR AMMONIA
Authors: PAGE GREGORY V. , SOLBERG MYRON
Published: August 2006

A study was conducted to determine whether Salmonella typhimurium could assimilate nitrogen from various inorganic nitrogen compounds in a chemically defined minimal medium. The organism was capable of utilizing nitrate, nitrite, and ammonia as sole nitrogen sources, but was unable to utilize hydroxylamine. The generation times calculated for S. typhimurium during anaerobic growth with either nitrite or ammonia as the nitrogen source were not statistically different indicating that these two nitrogen compounds were assimilated at comparable rates. Faster generation times were observed when nitrate was provided as the sole nitrogen source while the fastest generation times were observed in anaerobic cultures containing both nitrate and ammonia. S. typhimurium utilized NaNO2, as the sole nitrogen source at concentrations as highas400 μg/ml (5.6 mM) but NaNO2, concentrations of 500 μg/ml (7.0 mM) and above resulted in complete inhibition.