bluuebunny/crossref_metadata_2025 huggingface dataset:
Microbiological, Sensory and Chemical Characteristics of Vacuum‐Packaged Ground Beef Patties Treated with Salts of Organic Acids
Authors: MACA J. V. , MILLER R. K. , ACUFF G. R.
Published: July 2006

Vacuum‐packaged ground beef patties containing sodium lactate (NaL), sodium propionate (NaP), sodium acetate (NaA) and sodium citrate (NaC) at various levels and combinations were stored up to 28 days at 4°C. Addition of sodium lactate alone or in combination with sodium propionate increased shelf life of the patties by decreasing microbiological growth and decreasing negative flavor notes associated with lipid oxidation. Lean color also was improved by addition of sodium lactate alone or in combination with sodium propionate. Lipid oxidation by TBA was only slightly affected by treatment addition or storage.
Calcium Bioavailability of Vegetarian Diets in Rats: Potential Application in a Bioregenerative Life‐Support System
Authors: NICKEL KWANGOK P. , NIELSEN S. SUZANNE , SMART DEBRA J. , MITCHELL CARY A. , BELURY MARTHA A.
Published: July 2006

Calcium bioavailability of vegetarian diets containing various proportions of candidate crops for a controlled ecological life‐support system (CELSS) was determined by femur 45Ca uptake. Three vegetarian diets and a control diet were labeled extrinsically with 45Ca and fed to 5‐wk old male rats. A fifth group of rats fed an unlabeled control diet received an intraperitoneal (IP) injection of 45Ca. There was no significant difference in mean calcium absorption of vegetarian diets (90.80 ± 5.23%) and control diet (87.85 ± 5.25%) when calculated as the percent of an IP dose. The amounts of phytate, oxalate, and dietary fiber in the diets did not affect calcium absorption.
Microfiltration and Reverse Osmosis Affect Recovery of Mango Puree Flavor Compounds
Authors: OLLE D. , BARON A. , LOZANO Y.F. , SZNAPER C. , BAUMES R. , BAYONOVE C. , BRILLOUET J.M.
Published: July 2006

Flavor compounds from ripe mango puree were studied upon cross‐flow microfiltration on microporous alumina membrane and subsequent concentration of the permeate by reverse osmosis. Terpene hydrocarbons, the major (−98%) volatiles of the puree, were qualitatively and quantitatively recovered in the pulpy microfiltration retentate. The more polar volatiles (−2%) were diversely affected. Most of the oxygenated terpene derivatives were also retained in the microfiltration retentate. C13 norisoprenoids and phenols increased, likely by chemical degradation of carotenoids and phenolic acids, respectively.
Bacterial and Autolytic Changes in Water Retention and Adenosine Nucleotides of Cod Mince
Authors: MUYONGA J.H. , REGENSTEIN J.M.
Published: July 2006

Water uptake ability (WUA), expressible moisture (EM), hypoxanthine (Hx), and inosine (HxR) were monitored in cod mince stored at 0, −2, −3°C, with or without bacterial inactivation using NaOCl. Hx and HxR increased (p < 0.05) in all samples during the first 9‐10 days. Bacterial inactivation reduced Hx and HxR build up. Beyond day 10, Hx and HxR decreased in all samples. The decrease was slower in samples in which bacterial had been inactivated. Bacterial inactivation deterred WUA increases and EM decrease.
Defined Starter Cultures used for Fermentation of Salmon Fillets
Authors: MORZEL MARTINE , FRANSEN NICOLINE G. , ARENDT ELKE K.
Published: July 2006

The integration of defined starter cultures into a fish fermentation process was studied. Six lactobacilli and 5 staphylococci strains were tested in a salmon model system. Dependence of bacterial growth and pH reduction on sucrose, NaCl and sodium nitrite concentrations, and fermentation temperature was evaluated. A combination of Lactobacillus sake and Staphylococcus carnosus was then applied to whole salmon fillets to which NaCl and sucrose had been added. The influence of sucrose and NaCl concentrations, temperature and the addition of sodium nitrite on pH, color and microbiological stability was evaluated. Optimal conditions were 25g‐kg−1 NaCl, 15gkg−1 sucrose, fermentation at 12°C for 3 days, subsequent storage at 4°C.
Endogenous Mycoflora of Gable‐top Carton Paperboard Used for Packaging Fruit Juice
Authors: NARCISO J.A. , PARISH M.E.
Published: July 2006

Studies were undertaken to isolate and identify filamentous fungi from gable‐top cartons used for fruit juice packaging. All containers studied were food‐grade, gable‐top cartons composed of paperboard with various laminants and coextruded layers. Paperboard fibers from surface sterilized pieces of blank (unfilled) cartons harbored 40 species of 14 genera and 6 Mycelia Sterilia isolates. A parallel study of juice‐filled cartons revealed 10 filamentous species and 3 Mycelia Sterilia isolates from deteriorated areas of the paperboard cartons. Three of 9 juice‐filled cartons contained mycelial mats ofPenicillium biformeandPenicillium spinulosumwithin the juice. These two species were also isolated from the paperboard.
Bioavailability of Calcium Citrate Malate Added to Microbial Phytase‐Treated, Hydrothermally Cooked Soymilk
Authors: LIHONO MAKUBA A. , SERFASS ROBERT E. , SELL JERRY L. , PALO PIERRE E.
Published: July 2006

Effects of microbial phytase on bioavailability of calcium added to corn/soy diets were investigated in chickens. No effect (P > 0.17) of phytase was found for weight gain, feed intake, tibia/body weight, ash%, and ash Ca% when calcium citrate malate (CCM) was added to corn/soybean meal and corn/hydrothermally cooked (HTC) soymilk diets. Using calcium carbonate in corn/HTC soymilk diets, means for weight gain, feed intake, tibia/body weight, and ash% were less (P < 0.05) without phytase. We hypothesize that CCM is less amenable to the formation of calcium phytate complexes than are other calcium salts and, therefore, should be more effective for fortification of soymilk products.
Prerigor Carcass Muscle Stretching Effects on Tenderness of Grain‐fed Beef Under Commercial Conditions
Authors: CLAUS JAMES R. , WANG HENGJIAN , MARRIOTT NORMAN G.
Published: July 2006

A prerigor cut was made through the 12th thoracic vertebrae and another skeletal cut through the ischium on the pelvic bone of one side of 16 USDA Choice and 9 USDA Select beef carcasses (TC), while the companion sides served as controls (C) under industry conditions. TC lowered CIE a* values and resulted in longer sarcomeres in the longissimus muscle (LM). Compared to the C samples, the LM from TC USDA Choice carcasses were rated 28% higher (more tender) in overall tenderness and treated USDA Select carcasses were 18% higher. Also, variation in tenderness of the LM among animals was reduced by the TC Process. For Gluteus medius and Rectus femoris (RF), the TC samples were also more tender.
Sensory and Physical Characteristics of Reduced‐Fat Turkey Frankfurters with Modified Corn Starch and Water
Authors: BEGGS KAREN L.H. , BOWERS JANE A. , BROWN DUANE
Published: July 2006

Twenty formulations for turkey frankfurters were evaluated using 2.379 to 6.621% modified corn starch and 20.93 to 35.07% water. Cooked frankfurters were evaluated by a descriptive panel. Internal color, compression, percentages fat and moisture, purge loss, and pH were measured. Levels of starch and water affected percentages of fat and moisture of the batter. Frankfurters with low levels of starch were more yellow, firmer, and not as cohesive as those with high levels. Frankfurters with high levels of water were softer, lighter in color, and juicier than those with less water. Increased levels of starch and water maximized organ meat/metallic flavor. For optimal sensory and physical attributes, the predicted levels should be starch 2.3% and added water 33.6%.
Mechanisms of Syneresis in Rennet Curd without Mechanical Treatment
Authors: RENAULT C. , GASTALDI E. , LAGAUDE A. , CUQ J.L. , DE LA FUENTE B. TARODO
Published: July 2006

An original method for syneresis evaluation was developed, based on image analysis which enabled direct monitoring of curd shrinkage. Image analysis was employed in combination with the customary tracer method to follow the effects of cutting on curd syneresis. The two methods were then utilized to study curd syneresis in the presence of ethanol, a solvent less polar than water. Curd syneresis was reduced in the presence of diluted ethanol which led to the hypothesis that the mechanism which causes rennet curd to synerese probably relates to changes in protein conformation, essentially due to hydrophobic bonding.
Dystrophin Cleavage and Sarcolemma Detachment are Early Post Mortem Changes on Bass (Dicentrarchus labrax) White Muscle
Authors: PAPA I. , TAYLOR R.G. , ASTIER C. , VENTRE F. , LEBART M.C. , ROUSTAN C. , OUALI A. , BENYAMIN Y.
Published: July 2006

Using specific dystrophin antibodies directed against a conserved C‐terminal sequence, we demonstrated that dystrophin of fish white muscle was quickly degraded by 50% within 24h and by 100% within 2 days, in parallel with titin cleavage and alpha‐actinin release from Z‐disks. These changes were accompanied by sarcolemma detachment from the myofibers in costameres (the structures containing dystrophin) and Z‐disks weakening. For muscle stored during 2 to 6 mo before thawing, total dystrophin disappearance was observed at 4°C in <8h. Dystrophin may serve as a marker for stored fish to evaluate post mortem changes or detect a thawing‐freezing process.
Dietary Vitamin E Affects Lipid Oxidation and Total Volatiles of Irradiated Raw Turkey Meat
Authors: AHN D.U. , SELL J.L. , JEFFERY M. , JO C. , CHEN X. , WU C. , LEE J.I.
Published: July 2006

Breast and leg meat patties, prepared from turkeys fed diets containing 25, 200, 400 or 600 IU of dl‐α‐tocopheryl acetate (TA) per kg diet, were irradiated at 0 or 2.5 kGy with vacuum or loose packaging. The effects of dietary TA on storage stability and production of volatiles in irradiated raw turkey meat were determined. Dietary TA at > 200 IU/kg decreased lipid oxidation and reduced total volatiles of raw turkey patties after 7‐days of storage. However, the antioxidant effects of dietary TA were more notable when the patties were loosely packaged than when vacuum‐packaged. Irradiation increased lipid oxidation of raw turkey meats only when loosely packaged but had limited effects on formation of total volatiles after storage at 4°C for 7 days or longer.
Agar‐Gel Immunodiffusion Test for Rapid Identification of Pollock Surimi in Raw Meat Products
Authors: DREYFUSS MOSHE S. , CUTRUFELLI MARK E. , MAGEAU RICHARD P. , McNAMARA ANN MARIE
Published: July 2006

A test for the rapid identification of raw pollock surimi (TRIPS) was developed. This was an adaptation of previously developed field screening agar‐gel immunodiffusion tests for speciation of meat products. It was specific for Alaska pollock surimi at 2% concentration and other surimis at higher concentrations, showed detectable sensitivity to surimi in meat at 2–4%, and was 100% accurate in detection in laboratory trials.
Catalytic Activities of Crude Enzyme Fractions from Monterey Sardine
Authors: LUGO‐SÂNCHEZ M.E. , PACHECO‐AGUILAR R. , YÉPIZ‐PLASCENCIA G.
Published: July 2006

Catalytic activities in sarcoplasmic fluid of Monterey sardine (Sardinops sagax caerulea) were identified. Hydrolysis at pH 7.6 on hippuryl‐L‐phenylalanine and hippuryl‐L‐arginine suggested the presence of carboxypeptidase A and B. Proteolysis on glutaryl‐L‐phenylalanine‐p‐nitroanilide, and inhibition by CuSO4, phenylmethylsulfonyl fluoride and N‐p‐tosyl‐L‐lysil chloromethyl ketone, confirmed presence of a chymotrypsin‐like proteinase and other serine enzymes. No hydrolysis on α‐N‐benzoyl‐D,L‐arginine‐p‐nitroanilide occurred. Leucine aminopeptidase was detected by hydrolysis on L‐leucyl‐β‐naplithylamide‐HCl. Activity at pH 3 proved the presence of an acid proteinase but a slight inhibition by EDTA suggested the involvement of a cathepsin D‐like enzyme. Cathepsins A and B and collagenase were not detected.
Solubilization of Fish Muscle Myosin by Sorbitol
Authors: KONNO KUNIHIKO , YAMANODERA KEN‐ICHI , KIUCHI HIDEKAZU
Published: July 2006

Sugars and their reduced forms decreased the turbidity of myofibril suspension in a concentration dependent relation. The extent of turbidity decrease was compound specific; glucose sorbitol lactitol = lactose=maltitol. Turbidity decreasing effect of sugars correlated well with the number of hydroxyl groups. Sorbitol reduced the NaCl concentration required for solubilization of myofibrils. Moreover, filament formation by myosin was strongly inhibited by sorbitol.
Color and Gel‐forming Properties of Horse Mackerel (Trachurus japonicus) as Related to Washing Conditions
Authors: CHEN HUI‐HUANG , CHIU E‐MEAN , HUANG JIN‐RU
Published: July 2006

A beneficial decoloration effect resulted for horse mackerel mince washed with ozonized water within 10–20 min, but a longer washing time was required to improve the color properties when cold water or alkaline solution was used. Increase in pH as well as improvements in gel‐forming ability occurred for mince washed with alkaline solution. The maximal gel strength of surimi was found when washed for 90 min. A marked decrease in pH and an undesirable gel strength of mince, as well as oxidation of the fish oil occurred during ozone treatment. Since the salt‐soluble protein concentration increased for all minces washed with the three methods, improvement in gel‐forming ability of washed mince was attributed to the increase in pH rather than to oil removal.
Physicochemical Changes in Dietary Fiber of Green Beans after Repeated Microwave Treatments
Authors: SVANBERG S.J. MARIA , SUORTTI TAPANI , NYMAN E. MARGARETA G‐L.
Published: July 2006

The influence of microwave cooking/reheating on dietary fiber in green beans was investigated. The beans were analyzed after blanching and following repeated microwave treatment. Content and composition of dietary fiber as well as molecular weight distribution and viscosity of indigestible water‐soluble polysaccharides (WSP) (Mw >1000) were determined. Total fiber content decreased only after the most severe microwave treatment, primarily due to losses of soluble dietary fiber (pectic polymers). Molecular weight and viscosity decreased considerably after the first microwave treatment. Repeated microwave treatments reduced the molecular weight further, but not the viscosity.
Temperature Measurement of Foods Using Chemical Shift Magnetic Resonance Imaging as Compared with T1‐weighted Temperature Mapping
Authors: KANTT CARLOS A. , WEBB ANDREW G. , LITCHFIELD J. BRUCE
Published: July 2006

A method based on change in proton precession frequency with temperature was compared with temperature measurement by T1‐weighted imaging. Temperature maps of a gel, and of cooked and raw red potatoes were developed during heating from 20 to 60°C. To measure change in proton precession frequency, a steady state free precession sequence allowed 2‐dimensional acquisitions in 8 sec with spatial resolution of 0.88 mm2. Temperature resolution with chemical shift imaging, ranged from 0.3 to 3°C, decreasing with increasing temperature due to a decrease in signal to noise ratio. The difference by this method and thermocouples was < 5°C. T1‐weighted spin‐echo images showed artifacts due to an inhomogeneous T1 distribution within the potatoes, indicating chemical shift was more reliable for inhomogeneous foods.
Hot‐Boning, Elevated Temperature Conditioning, and Vacuum Packaged Aging Influences on Lamb Cooking Losses and Palatability
Authors: JEREMIAH L.E. , TONG A.K.W. , GIBSON L.L.
Published: July 2006

Wether lambs (64) were utilized to examine the effects of hot‐boning (HB), elevated temperature conditioning (ETC) and vacuum packaged aging (VPS) on the cooking properties and palatability attributes of racks. Samples were HB at approximately 45 min post‐mortem and ETC for 0, 2, 4, or 6 hr at 32°C. Following ETC, samples were VPS for 6, 13, 27, or 41 days at 1–2°C. Wholesale racks could be HB at 45 min without influencing cooking losses or palatability attributes (P>0.05). VPS, however, improved initial and overall tenderness and reduced the amount of perceptible connective tissue, but increased total cooking losses, reduced juiciness, and intensified flavor (P<0.05).
Optimum Measure of Cap Color in Agaricus bisporus Wild and Cultivated Strains
Authors: MOQUET F. , GUEDES‐LAFARGUE M. RAMOS , VEDIE R. , MAMOUN M. , OLIVIER J.M.
Published: July 2006

Cap color was characterized on a wide range of Agaricus bisporus strains. L, a and b tristimulus coordinates were tested by linear model analysis to determine color information related to each parameter. One model was retained: log(L/(100‐L)) =α* H +β. Visual cap color variation was continuous and well described by log(L/(100‐L)) or H parameters. In the wild, the range of color varied from white to dark brown which would enable mushroom breeding for cap color adapted to the market.
Vapor Pressure of Allyl Isothiocyanate and Its Transport in PVDC/PVC Copolymer Packaging Film
Authors: LIM LOONG‐TAK , TUNG MARVIN A.
Published: July 2006

Equilibrium vapor pressures of allyl isothiocyanate (AIT) above pure AIT and AIT/canola oil mixtures from 15 to 45°C were estimated from AIT vapor densities using gas chromatography. Canola oil was an effective diluent for depressing AIT vapor pressure. Permeation of AIT in a PVDC/PVC copolymer film was measured using the dynamic quasi‐isostatic method, and kinetics of AIT vapor sorption in the polymer were studied gravimetrically. Experiments were carried out at 25, 35 and 45°C with vapor pressures from 50 to 800 Pa. At fixed vapor activity, diffusion and permeability coefficients increased with temperature, but a decrease was observed for solubility coefficient. An empirical equation was used to describe the sorption kinetics.
Piezoelectric Biosensor for Detection of Salmonella typhimurium
Authors: YE JIANMING , LETCHER STEPHEN V. , RAND ARTHUR G.
Published: July 2006

A flow injection analysis (FIA) system was developed based on a piezoelectric biosensor for detection of Salmonella typhimurium. The anti‐Salmonella spp antibody was immobilized onto the gold electrode coated quartz crystal surface through a polyethylenimine‐glutaraldehyde (PEG) technique and dithiobis‐succinimidyl propionate (DSP) coupling. The PEG technique proved more successful for FIA applications than the DSP coupling. The biosensor had responses of 23–7 Hz in 25 min when the PEG immobilization technique was employed, with R20.94 for Salmonella typhimurium concentrations of 5.3.105 to 1.2.109 CFU/mL.
Lactic Fermentation of Media Containing High Concentrations of Yeast Extracts
Authors: GAUDREAU H. , CHAMPAGNE C.P. , GOULET J. , CONWAY J.
Published: July 2006

Yeasts extracts (YE) were supplemented with whey permeate and citrate (YPC) as substrates for lactic acid and diacetyl production. Lactococcus lactis ssp. lactis AD was selected for high production of lactic acid and diacetyl. High correlation (r2= 0.88) occurred between acidification and population increases in YPC containing 70 g/L YE. Media with 100 g/L YE were inhibitory to growth. YPC supplementation with M17 or MRS had little effect on growth but reduced diacetyl. Increasing incubation temperature to 25°C stimulated fermentation but a temperature rise to 30°C only increased lactic acid. With 2L fermenters (20°C/110 rpm) on YPC (70 g/L YE) maximal diacetyl was obtained between 12–16h, and maximal population was obtained after 22h. Fermenter‐production of diacetyl in YPC was comparable to that in milk (1 to 10 ppm) but less than that in shake flasks (32 ppm).
Dietary Influences on Bovine Milk cis‐9,trans‐11‐Conjugated Linoleic Acid Content
Authors: STANTON C. , LAWLESS F. , KJELLMER G. , HARRINGTON D. , DEVERY R. , CONNOLLY J.F. , MURPHY J.
Published: July 2006

The effects of grass dry matter (DM) allowance and dietary supplements of full fat rapeseeds on levels of cis‐9,trans‐11 octadecadienoic (CLA) acid in bovine milk were investigated. Grass allowance of 16 kg/(cow*day) resulted in reduced (p<0.05) milk fat CLA levels (3.91 mg CLA/g fat) compared to 20 kg/(cow*day) after 19 wk treatment. CLA levels increased in milk fat from cows on a high‐rapeseed‐supplemented diet (p<0.001) (1650 g/(cow*day) full fat rapeseed) compared to the control (pasture) and low rapeseed (p<0.01) (825 g/(cow*day) full fat rapeseed) supplemented diets. The variation in milk fat CLA levels among individual cows over both trials was 1.5–16 mg/g.
Physical and Sensory Properties of Model Foods Supplemented with Cauliflower Fiber
Authors: FEMENIA A. , LEFEBVRE A.‐C. , THEBAUDIN J.‐Y. , ROBERTSON J.A. , BOURGEOIS C.‐M.
Published: July 2006

Cauliflower floret/curd and stem, as by‐products of processing, are a source of pectic‐polysaccharide‐rich fiber concentrates for use as water and oil binding agents and textural agents to improve the properties of model foods. Dehydration resulted in a 10% decrease in methyl esterification at above 40°C. Water retention capacity of florets (40°C) was reduced from 12.8 g/g to 5.7 g/g in 75°C dried samples, demonstrating the importance of matrix structure rather than polysaccharide composition for functional properties. Incorporation gave a 10% increase in the yield of beefburgers and a partial substitution for purified gums in sauces. Cauliflower fibers can be incorporated into food systems at concentrations found in vegetables but sensory characteristics depend on processing history.
Mathematical Models of Flavor Release from Liquid Emulsions
Authors: HARRISON MARCUS , HILLS BRIAN P. , BAKKER JOKIE , CLOTHIER TRACEY
Published: July 2006

The penetration theory of interfacial mass transfer was used to model flavor release from liquid emulsions. The model was used to predict the rates of release and partitioning properties of two volatiles, one hydrophilic (diacetyl) and the other hydrophobic (heptan‐2‐one), as a function of the oil volume fraction. In general the initial rates of release were faster for emulsions of lower oil content, whereas the equilibrium concentrations depended on the nature of the flavor compound and the volume fraction of oil in the emulsion. Experimental in vitro results suggested that the rate limiting step for flavor release was the resistance to mass transport across the emulsion‐gas interface.
Free‐Volume Changes in Flexible, Hermetic Packages Containing Respiring Produce
Authors: TALASILA PANCHANADHAM C. , CAMERON ARTHUR C.
Published: July 2006

To investigate free‐volume changes in flexible, sealed packages containing respiring fruits and vegetables, a simple method based on the dilution of an injected gas (ethane) in the package was developed. Free‐volume decreased steadily at ∼3 cm3/day after an initial transient period in low‐density polyethylene packages (29‐μm‐thick film; 600‐cm2 surface area; initial free volume ∼285 cm3) containing 40g of cut broccoli held at 0°C. A general transient model was developed that showed that free‐volume changes in flexible packages were a function of differential film O2, CO2, and N2 permeabilities and differential product O2 uptake and CO2 production rates. The model predicted that flushing packages with low permeative gases would decrease free‐volume depletion rate, whereas flushing with highly permeative gases, such as CO2, would increase the initial rate considerably.
Debittering Casein Hydrolysates with Octadecyl‐Siloxane (C18) Columns
Authors: LIN SHIH‐BIN , NELLES LYNN P. , CORDLE CHRISTOPHER T. , THOMAS RONALD L.
Published: July 2006

Three casein hydrolysates (degree of hydrolysis (DH) of 23, 47, and 65.5 (%)) were debittered using three different hydrophobic adsorption columns, C18, C8, and phenolic resin (PR). Higher DH hydrolysates resulted in higher total nitrogen yields through the debittering process. The C18 and PR columns had more effective debittering than the C8 column, which had the highest processing yield. The PR column had much lower processing yield than the C18 column. Q‐value correlated with bitterness in the hydrolysates. Antigenicity of treated hydrolysates was reduced by the debittering process.
Acid Milk Gel Formation as Affected by Total Solids Content
Authors: GASTALDI E. , LAGAUDE A. , MARCHESSEAU S. , DE LA FUENTE B. TARODO
Published: July 2006

Reconstituted skim milk with varying concentrations of total solids was coagulated using glucono‐δ‐lactone (GDL). Microscopic, turbidimetric and rheological procedures were used to examine mineral solubilization, buffering capacity, casein dissociation and micellar solvation during gelation. Total solids of the milk affected pH of the onset of gelation attributable to differences in colloïdal calcium phosphate in the casein particles during acidification. Firmness and elasticity of the resulting gel increased with total solids from a more direct contribution of dry matter during the last stage of acid milk gel formation.
Gelling Properties of Gellan Solutions Containing Monovalent and Divalent Cations
Authors: TANG J. , TUNG M.A. , ZENG Y.
Published: July 2006

Gelling temperatures of gellan solutions with the addition of Na+ and K+ ranging from 15 to 450 mM or Ca++ and Mg++ from 2 to 40 mM were determined by dynamic rheological testing at four polymer concentrations between 0.4 and 2.0% (w/w). Gelling temperatures were much higher for gellan solutions containing divalent cations than for those containing the same amount of monovalent cations. Solutions containing K+ gelled at higher temperatures than those containing Na+. Effects of Ca++ and Mg++ on gelling temperatures were not significantly different. A general model was developed to predict the gelling temperature of gellan solutions as functions of cation and polymer concentrations.
Residual Moisture Content as Related to Collapse of Freeze‐dried Sugar Matrices
Authors: BONELLI PABLO , SCHEBOR CAROLINA , CUKIERMAN ANA L. , BUERA MARÍA P. , CHIRIFE JORGE
Published: July 2006

Amorphous sugars were prepared by freeze‐drying 20% (w/w) aqueous solutions of lactose, sucrose, trehalose and maltose. The dried samples were further dehydrated over P2O5 for 1 wk at 25, 35 or 45°C, and the residual moisture content was determined using oven drying or a thermogravimetric balance. Results indicated a small amount of residual moisture (usually 1–2%) which was not removed by the desiccation treatment for 1 wk at 25°C over P2O5. The dried samples, heated at a temperature near the published “anhydrous” glass transition temperatures (Tg) exhibited different behavior depending on whether they were heated in open or sealed vials. Structural collapse, a sharply visible shrinkage of the matrix, was found in all samples in sealed vials, while those samples in open vials did not collapse. Thus, removal of the last amount of residual moisture by heating in uncovered vials increased Tg, preventing or delaying collapse.
Hydrolytic Stability and Changes in E Vitamers and Oryzanol of Extruded Rice Bran During Storage
Authors: SHIN TAI‐SUN , GODBER J. SAMUEL , MARTIN DANIEL E. , WELLS JOHN H.
Published: July 2006

Rice bran was extruded at 110, 120, 130, and 140°C with post extrusion holding times of 0, 3, and 6 min and stored at ambient temperatures for 1 yr. Holding time had no effect (p>0.05) on hydrolytic stability whereas 110°C was slightly less effective in maintaining hydrolytic stability. Increased holding times reduced (p<0.05) total vitamin E content. Oryzanol concentration was lower (p<0.05) only after 6 min holding time. Oryzanol was relatively more stable to extrusion temperatures than vitamin E. The highest retentions of total vitamin E and oryzanol were found in raw rice bran during storage. Increased extrusion temperatures reduced the retention of vitamin E and oryzanol during storage.
Structural Changes in Cod Myosin after Modification with Formaldehyde or Frozen Storage
Authors: CARECHE M. , LI‐CHAN E.C.Y.
Published: July 2006

Structural changes in cod myosin after formaldehyde (FA) addition with and without subsequent freezing at – 18°C were examined by Raman spectroscopy, ANS hydrophobicity, solubility and SDS‐PAGE profiles. Protein solubility decreased by >90%, whereas ANS fluorescence showed little change, possibly due to a balance between soluble and insoluble fractions differing in exposed hydrophobicity. SDS‐PAGE showed irreversible insolubilization at increasing FA concentration, especially after frozen storage. Raman spectral analysis indicated a change in secondary structure of aquacide concentrated myosin preparations, from 95%α‐helix in the control (no FA) to 60% after 12 mM FA treatment. Changes in vibrational modes assigned to aliphatic residues suggested involvement of hydrophobic interactions after FA addition or frozen storage.
Physicochemical Changes in Pacific Whiting Muscle Proteins during Iced Storage
Authors: BENJAKUL SOOTTAWAT , SEYMOUR THOMAS A. , MORRISSEY MICHAEL T. , AN HAEJUNG
Published: July 2006

No changes in actomyosin Ca2+‐, Mg2+‐, or Mg2+‐Ca2+‐ATPase activities were observed during iced storage of Pacific whiting fillets, but Mg2+‐EGTA‐ATPase increased with a loss of Ca2+‐sensitivity. Surface hydrophobicity of actomyosin increased substantially within 2 days, but not total sulfhydryl (SH) content. During longer storage, the SH content decreased gradually, but surface hydrophobicity remained constant. Autolytic degradation products increased in fish muscle with storage time. Myosin heavy chain (MHC) was degraded by 45% within 8 days, but no noticeable difference was observed in actin. Results indicated that autolysis may be the main cause of physicochemical changes in Pacific whiting muscle proteins during iced storage.
Trypsin Treatment to Improve Freeze Texturization of Minced Bream
Authors: KOLAKOWSKI EDWARD , WIANECKI MAREK , BORTNOWSKA GRAZNA , JAROSZ RENATA
Published: July 2006

Mild trypsin proteolysis (enzyme concentration 0.05% at 15°C, pH 7.4; mixing 30 min at 20 rpm) of bream mince improved mince susceptibility to freeze texturization. Formation of porous‐fibrous texture of heat‐set, freeze‐texturized minces was associated with strong fragmentation of myosin heavy chain (MHC), decrease in extractability of myofibrillar protein and increased insoluble protein and thermal drip. Some deamidation of protein was also observed. We concluded that limited trypsin proteolysis accelerated transglutaminase mediated cross‐linking of protein by acyl transfer reactions. Protein polymerization through plastein reactions and intermolecular hydrophobic interaction probably also occurred.
Microstructure of Yolk from Fresh Eggs by Improved Method
Authors: MINEKI MACHIKO , KOBAYASHI MASAHIKO
Published: July 2006

Methods were examined to fix hen's egg yolk while retaining its original sol structure and to elucidate the fine structure of fresh yolk by using the freeze‐cutting fixation method with liquid nitrogen. In fresh native yolk, histological differences were observed in the yolk spheres in each layer and latebra part. These spheres were closely packed in the vitelline membrane, with various sizes and shapes. Protein granules with high electron density were noted in the yolk sphere and their distribution and shape differed between the outer and inner layers.
Thin Film Rheology and Tribology of Chocolate
Authors: LUENGO GUSTAVO , TSUCHIYA MASARU , HEUBERGER MANFRED , ISRAELACHVILI JACOB
Published: July 2006

We investigated relations between food texture and thin film properties rather than bulk properties. Such thin film rheological or‘tribological’effects may characterize physical behavior and physical perceptions of food products. Experiments were done on three chocolate samples. The Surface Forces Apparatus (SFA) proved to be effective for studying the very complex chocolate system. Very complex thin film behavior was found to be quite different for the three samples. Fat constitution and average particle size were important in determining the type of friction forces generated between shearing/sliding surfaces separated by thin films of chocolate. Such studies can help characterize specific physical qualities of chocolate.
Color and Firmness Classification of Fresh Market Tomatoes
Authors: EDAN YAEL , PASTERNAK H. , SHMULEVICH I. , RACHMANI D. , GUEDALIA D. , GRINBERG S. , FALLIK E.
Published: July 2006

A total of 370 tomatoes from two seasons were analyzed using a vision system and three mechanical properties sensors which measured firmness parameters. Multiple linear regression indicated classification based on color and firmness could be applied in practical sorting and improves overall classification. Hue values provided adequate information for classification. The best model (R2= 0.96) based on 13 specific colors yielded severe misclassification of 2.2% for classification into 12 maturity classes and 79% correct classification with all samples classified ± one maturity stage according to USDA standards. A weighted color parameter provided a stable model invariant to changes in lighting conditions and yielded excellent results (R2= 0.89). Quality classification was successfully achieved using a vision and drop impact sensor.
High‐Pressure‐Freezing Effects on Textural Quality of Carrots
Authors: FUCHIGAMI MICHIKO , KATO NORIKO , TERAMOTO AI
Published: July 2006

Raw or 3 min blanched carrots were pressurized for 45 min at −18°C ∼–20°C and then thawed at 20°C. When carrots were frozen at 100Mpa (ice I), firmness decreased and strain increased. Textural values of carrots pressurized at 200MPa (liquid), 340MPa (ice III), 400MPa (ice V) at ca. –20°C were acceptable. When pressure was increased above 500MPa, the strain increased. Release of pectin and histological damage in carrots pressurized at 200, 340 and 400MPa were less than carrots frozen at 100 and 700MPa (ice VI). After pressurization at 200 and 340MPa at —20°C, carrots were stored in a freezer (–30°C). Firmness decreased and strain increased, but textural values were higher and histological structure were more intact than those frozen at –30°C (0.1MPa) then stored. Thus, high‐pressure‐freezing at 200, 340 and 400MPa appeared to be effective in improving both the texture and histological structure of frozen carrots.
Extrudates of Starch‐Xanthan Gum Mixtures as Affected by Chemical Agents and Irradiation
Authors: HANNA MILFORD A. , CHINNASWAMY RANGAN , GRAY DARREN R. , MILADINOV VESSELIN D.
Published: July 2006

Mixtures of starch, xanthan gum and either polyvinyl alcohol, epichlorohydrin, valeric acid or adipoyl chloride were extruded. Properties of extrudates including apparent viscosity, water solubility, water absorption indices and exrudate expansion were measured for different proportions of xanthan gum, 70% amylose starch (with or without irradiation) and chemical agents. Extrusion with chemical agents and irradiation changed physical properties of both starch and xanthan gum. Expansions of extrudates were higher than that of starch. Viscosity of extrudates increased with xanthan gum concentration. The addition of 1% (w/w) polyvinyl alcohol had the greatest effect of the chemical agents. Irradiation increased the apparent viscosity of starchxanthan gum mixtures.
Modified Soy Proteins with Improved Foaming and Water Hydration Properties
Authors: WERE L. , HETTIARACHCHY N.S. , KALAPATHY U.
Published: July 2006

Soy proteins were modified by alkali treatment at pH 10.0, followed by papain hydrolysis. Solubility, water hydration capacity (WHC), surface hydrophobicity, foaming and emulsifying properties of unmodified, alkali‐treated, and papain‐modified soy protein (PMSP) were compared. PMSP exhibited higher solubility (100% at pH > 7.0), WHC (3.13) and hydrophobicity (40.8) than unmodified soy protein which had solubility 68.5%, WHC 0.21, and hydrophobicity 8.1. The PMSP had foaming capacity (22.0 mL) similar to egg white (21.2 mL) at pH 7.0; and enhanced foam stability (36.4) compared to the unmodified control (32.9). In general, alkali‐treated soy had lower functional properties. Emulsifying properties of PMSP and alkali treated soy were unchanged by the modification. PMSP could be used as an egg white substitute in foaming applications at neutral pH.
Structural and Textural Changes in Kinu‐Tofu Due to High‐Pressure‐Freezing
Authors: FUCHIGAMI MICHIKO , TERAMOTO AI
Published: July 2006

To determine the effect of high‐pressure‐freezing on quality, kinu‐tofu (soybean curd) was frozen at 100 MPa (ice I), 200 MPa (liquid phase), 340 MPa (ice III), 400, 500, 600 MPa (ice V) or 700 MPa (ice VI) at ca. –20°C for 90 min. After reduction to atmospheric pressure, tofu was stored 2 days at –30°C then thawed at 20°C. Texture and structure were compared with kinu‐tofu frozen (–20°C, –30°C or –80°C) at atmospheric pressure (0.1 MPa). The rupture stress and strain of tofu frozen at 0.1 MPa and 100 MPa increased, but that of tofu frozen at 200 MPa and 340 MPa was similar to untreated tofu. As pressure rose above 500 MPa, rupture stress increased. The ice crystals in tofu frozen at 200 MPa ∼400 MPa were smaller than in tofu frozen at 100 MPa or 700 MPa. Thus, high‐pressure‐freezing at 200 MPa ∼400 MPa was effective in improving the texture of frozen tofu.
High Pressure Treatment of Milk and Effects on Microbiological and Sensory Quality of Cheddar Cheese
Authors: DRAKE M.A. , HARRISON S.L. , ASPLUND M. , BARBOSA‐CANOVAS G. , SWANSON B.G.
Published: July 2006

The effect of cycled high pressure treatment of milk on the yield, sensory, and microbiological quality of Cheddar cheese was investigated. Cheddar cheeses were made from pasteurized, raw, or pressure treated milk according to traditional methods. Flavor scores from trained dairy judges were not different for pasteurized and pressurized milk cheeses (P≤0.05). Percent moisture and wet weight yields of pressure treated milk cheeses were higher than pasteurized or raw milk cheeses (P≤0.05). Microbiological quality of pressurized milk cheeses was comparable to pasteurized milk cheeses. Texture defects were present in pressurized milk cheeses and were attributed to excess moisture. High pressure treatment of milk shows promise as an alternative to heat pasteurization prior to cheesemaking.
Growth of Staphylococcus aureus as Related to 17O NMR Water Mobility and Water Activity
Authors: LAVOIE J.P. , LABBE R.G. , CHINACHOTI P.
Published: July 2006

17O NMR data were determined for three solute‐BHI (Brain Heart Infusion) mixtures. For each solute, NaCl, raffinose and glycerol, NMR data (linewidths and signal intensity) were determined as well as water activity (aw), moisture contents, and effects on growth of Staphylococcus aureus in media of various moisture contents. Liquid (highly mobile) water content in all media tested was determined by NMR. This mobile water was important and had a stronger correlation with S. aureus growth rate than did aw or moisture content, although solute effects limited empirical prediction. NMR linewidth also correlated with lag phase.
Polyamines Affect Activity of Aminopeptidases from Lactobacillus sake
Authors: SANZ YOLANDA , TOLDRÁ FIDEL
Published: July 2006

The effects of polyamines (agmatine, cadaverine, putrescine, spermidine and spermine) on the activity of the main aminopeptidases (AP I and AP II) from Lactobacillus sake were determined. Concentrations in the range of 1 mM caused 6–25% inhibition of AP I except for spermine (45% inhibition). Higher polyamine levels (5–10 mM), except for putrescine, exerted a stronger inhibition (20–60%) on AP I. Agmatine and putrescine also reduced AP II activity (6–25%) at concentrations of 0.1–10 mM while cadaverine did not have a notable effect. Spermidine and spermine stimulated (15–70%) the activity of AP II at concentrations >1 mM. Thus, control of polyamine levels is important because they are a potential hazard for human health and also because of their effects on aminopeptidase activity.
Sensory Descriptive Profile Relationships to Shear Values of Deboned Poultry
Authors: LYON B.G. , LYON C.E.
Published: July 2006

Poultry breasts were deboned at 2, 6, and 24h post‐mortem to provide ranges of characteristics to test instrumental and sensory tenderness relationships. Sensory descriptive texture attributes were separated by Variable Cluster Analysis into five groups representing mechanical, moisture, and chewdown characteristics. Warner‐Bratzler and Allo‐Kramer shear values indicated differences due to deboning time and correlated highly (r≥0.90) with mechanical and chewdown sensory characteristics. However, texture profiles of samples in shear value ranges corresponding to consumer‘tender‐tough’categories showed that texture remained differentiated by deboning times. Particle size, bolus and wetness characteristics interacted with minor attributes of saliva, ease of swallow, and mouthcoating to contribute to sensory perceptions and differentiations of texture.
Handling Stress and Storage Temperature Affect Meat Quality of Farmed‐raised Atlantic Salmon (Salmo Salar)
Authors: SIGHOLT T. , ERIKSON U. , RUSTAD T. , JOHANSEN S. , NORDTVEDT T.S. , SELAND A.
Published: July 2006

Salmon slaughtered by standard routines (control) or stressed by confinement for 10 min before stunning and then stored at 0.4 or 3.3°C for 9 days were compared. Handling stress led to lower muscle phosphocreatine (p<0.001), adenosine‐5′‐triphosphate (p<0.05) and shorter pre‐rigor period. Storage temperature affected external quality index, white muscle pH and K‐value (degradation products of ATP). Stress produced a softer fillet (p<0.001). A lower breaking strength (p<0.01) was found in fish stored at 0.4°C. Sensory tests distinguished the control/stress groups within the 0.4°C chilling regime and the 0.4°C/3.3°C chilling groups within the control regime. Stress caused a lower score for texture (p<0.05) both at 0.4 and 3.3°C and for odor at 3.3°C in a descriptive sensory test. No detectable effects of stress or storage temperature were found on flavor or color.
Training and Sensory Judgment Effects on Mastication as Studied by Electromyography
Authors: MIOCHE LAURENCE , MARTIN JEAN‐FRANÇOIS
Published: July 2006

Electromyography recordings (EMG) were performed on 10 naive and 10 trained subjects during mastication of different samples of beef. For each group of subjects, ordinary mastication was compared to mastication accompanied by tenderness assessment of the chewed sample. Trained subjects showed a larger variation in muscle work than a naive group when chewing. Sensory assessment modified more the mastication profiles of trained subjects than those of naive ones and these variations occurred at the beginning of the masticatory sequence. EMG was useful for comparing mastication of different groups of panelists and appeared to be an interesting alternative for information about texture perception of naive subjects.
Viscoelasticity of Frozen/Thawed Egg Yolk as Affected by Salts, Sucrose and Glycerol
Authors: TELIS V.R.N. , KIECKBUSCH T.G.
Published: July 2006

Based on dynamic rheological measurements, sucrose, glycerol and magnesium chloride (MgCl2) prevented egg yolk gelation at concentrations of 2% and higher. These additives showed improved cryoprotectant effects as their concentrations were increased. Sodium chloride (NaCl) at higher than 2% also prevented gelation but at 10%, it caused a considerable increase in viscosity of unfrozen yolk. Calcium chloride (CaCl2) showed an opposite effect, promoting protein coagulation before freezing. Samples with 2% CaCl2 gelled completely after 36h at ‐24°C. Before freezing, potassium chloride (KCl) in the range 2–10% had an effect similar to that of NaCl. However, after freezing its effect changed. Yolk with 2% KCl, frozen 36h at ‐24°C, showed very elastic behavior.
Emulsion Stability as Affected by Competitive Adsorption Between an Oil‐Soluble Emulsifier and Milk Proteins at the Interface
Authors: CORNEC MICHEL , WILDE PETER J. , GUNNING PAUL A. , MACKIE ALAN R. , HUSBAND FIONA A. , PARKER MARY L. , CLARK DAVID C.
Published: July 2006

The effect of an oil‐soluble emulsifier upon adsorption properties of β‐casein and β‐lactoglobulin at the oil‐water interface was studied. Addition of emulsifier improved the emulsification properties, but lowered emulsion stability. Higher concentrations decreased emulsification capacity, due to an increase in oil phase viscosity, and interfered with several protein assays, except the o‐phthaldialdehyde (OPA) assay. Depletion measurements revealed that the emulsifier displaced β‐casein more readily than β‐lactoglobulin from the surface of droplets, which correlated with emulsification and stability measurements. Displacement of proteins was not complete due to emulsifier‐induced formation of a multiple w‐o‐w emulsion, which accounted for the missing protein in the continuous phase.
Tropomyosin, the Major Oyster Crassostrea gigas Allergen and its IgE‐binding Epitopes
Authors: ISHIKAWA MASARU , ISHIDA MASAMI , SHIMAKURA KUNIYOSHI , NAGASHIMA YUJI , SHIOMI KAZUO
Published: July 2006

The major allergen (Cra g 1) isolated from the oyster Crassostrea gigas was digested with lysylendopeptidase. Twenty‐one peptide fragments were isolated from the digest by reverse‐phase HPLC and some of them were sequenced. Cra g 1 was identified as tropomyosin. In competitive ELISA inhibition analyses of lysylendopeptidase fragments, a peptide (K21) showed maximum inhibition of the binding of IgE antibodies in sensitive human serum to Cra g 1. On further tryptic hydrolysis of K21, two peptides exhibited high inhibitory ability equivalent to K21. These results suggested that Cra g 1 had an IgE‐binding epitope in the segment 92–105 (IQLLEEDMERSEER) which was dissimilar to those of the major allergen (tropomyosin) from the shrimp Penaeus indicus.
Limonoids and Flavonoids in Juices of Oroblanco and Melogold Grapefruit Hybrids
Authors: HSU WAN‐JEAN , BERHOW MARK , ROBERTSON GEORGE H. , HASEGAWA SHIN
Published: July 2006

Oroblanco and Melogold are hybrids obtained from pummelo and grapefruit. Limonoids and flavonoids in both juices were analyzed. Oroblanco and Melogold juices contained low concentrations of limonoid glucosides, an average of 99 and 59 ppm, respectively. However, they contained relatively high concentrations of bitter limonoid aglycones, limonin and nomilin, at levels above the limonin bitterness threshold. For comparison, limonoid glucosides in juices of grapefruit, another pummelo hybrid, were also analyzed. Limonin glucoside was the major limonoid glucoside in all juices analyzed. Nomilin glucoside and nomilinic acid glucosides were also present. Oroblanco and Melogold juices contained bitter flavonoids normally found in grapefruit and pummelo including naringin, neohesperidin and poncerin in total amount of 440 ppm in Oroblanco juice and 495 ppm in Melogold juice. They also contained several other nonbitter flavonoids found in grapefruit.
Naringinase Immobilization in Packaging Films for Reducing Naringin Concentration in Grapefruit Juice
Authors: SOARES N.F.F. , HOTCHKISS J.H.
Published: July 2006

Naringin, a bitter compound in citrus, may be converted to a nonbitter form by enzymic hydrolysis. Our objective was to determine the feasibility of immobilizing naringinase in a food contact approved packaging film. Naringinase from Penicillium sp. was immobilized in cellulose acetate films with up to 23% efficiency at 7°C. Kinetic studies showed that the free enzyme had an optimum pH=3.5 and the immobilized enzyme pH=4.0. Activation energy decreased upon immobilization (from 14.2 to 11.0 Kcal/mol), thus providing an increased catalytic efficiency for immobilized naringinase. The Michaelis constant for immobilized naringinase (Km=2.1 mM) was lower than for free enzyme (Kmm=3.6 mM). Keeping films under dry storage for 1 mo at room temperature did not cause decreased enzyme activity. A film area/volume ratio (cm2/mL of 10° Brix grapefruit juice) of 7.2 hydrolyzed 60% of the naringin in 15 days at 7°C.
Repeated Regeneration of Degraded Red Beet Juice Pigments in the Presence of Antioxidants
Authors: HAN DAESEOK , KIM SEOK JOONG , KIM SANG HEE , KIM DONG MAN
Published: July 2006

Ascorbic, isoascorbic, metaphosphoric, and gluconic acids improved the regeneration of red beet juice pigments after heating, and resulted in greater retention of the pigments during processing and storage. Their effect varied depending on the pH of the juice solutions. Ascorbic and isoascorbic acids allowed for the greatest regeneration at pH 3.8. At pH 6.2, metaphosphoric acid and gluconic acid were more effective. Addition of ascorbic acid once prior to the first heating retained the initial concentration of pigments even after 5 cycles of heating (3 min at 100°C) and regeneration. Control solution lost red pigments completely.