bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification of 5α‐Cholestane‐3β,5,6β‐triol and Other Cholesterol Oxidation Products in Fast Food French Fried Potatoes
Authors: ZHANG W.B. , ADDIS P.B. , KRICK T.P.
Published: August 2006

Concerns about toxicity of cholesterol oxidation products (COPS) prompted this study. Two restaurants were selected which use animal‐vegetable (A/V) shortening for deep‐frying. The survey of COPS for 30 days indicated values for total COPS in French fried potatoes were 20 ± 9 ppm to 24 ± 6 ppm. 5α‐Cholestane‐3β,5,6β‐triol (triol) was identified in French fried potatoes from one restaurant. The mean for triol was 9 ± 3 ppm. Triol, 7α‐hydroxycholesterol, 7β‐hydroxy‐cholesterol and 7‐ketocholesterol were confirmed by co‐chromatography and mass spectrometry. Triol is one of the most potent of angiotoxic COPS. This and other studies suggested French fried potatoes and other deep fried foods cooked in A/V shortening are a major source of COPS.
Thermal Gelation Mechanism of Legumin from Broad Beans
Authors: ZHENG BAI‐AN , MATSUMURA YASUKI , MORI TOMOHIKO
Published: August 2006

The legumin formed a gel through formation of soluble aggregates and their juncture. Electron microscope studies indicated the legumin molecules associated to form strands. These strands then formed network‐like structures, finally resulting in gel formation. The thickness of those strands and network constituents was irregular (8.3 to 36 nm). A presumed process of thermal legumin gelation was hypothesized. A comparison of gelation behaviors in legumin and in glycinin was also studied.
Changes in Gelling Behavior of Whey Protein Isolate and β‐Lactoglobulin During Storage: Possible Mechanism(s)
Authors: RECTOR D. , MATSUDOMI N. , KINSELLA J.E.
Published: August 2006

Dry‐heat treatment of a dialyzed whey protein isolate at 80°C for 7 days resulted in a decrease in hardness (from 1.55N to 0.49N) of gels formed from a 12% solution. Partial denaturation and progressive polymerization of protein was observed. The monomeric β‐lactoglobulin concentration of the whey decreased from 60.64% to 33.33%after 7 days at 80°C. The rate constants determined at 40 to 80°C were used to calculate an Arrhenius relationship for the polymerization. After one year at 25oC, 18% of monomeric β‐lactoglobulin was projected to be converted to higher‐molecular‐weight material. The polymerization apparently did not involve disulfide cross‐links.
Factors Influencing Whey Protein Gel Rheology: Dialysis and Calcium Chelation
Authors: KUHN PATRICIA R. , FOEGEDING E. ALLEN
Published: August 2006

Influence of dialyzable compounds on the Theological properties (shear stress and shear strain at failure) of heat‐induced whey protein concentrate (WPC) and whey protein isolate (WPI) gels was examined. Dialyzing WPC and WPI suspensions prior to gelation increased the stress of two of three WPC gels and a WPI gel. Dialysis also significantly increased the strain of the same two WPC gels, normalizing all strain values. Replacement of calcium lost through dialysis did not significantly change gel rheology. However, chelating calcium caused a significant decrease in the stress of all gels: a minimum amount of calcium and/or a calcium complex appears to have a major role in whey protein gelation.
Coalescence Index of Protein‐Stabilized Emulsions
Authors: BRITTEN MICHEL , GIROUX HÉLÈNE J.
Published: August 2006

A simple method is proposed to estimate coalescence stability of protein‐stabilized emulsions. Coalescence was accelerated through agitation and measured by change in emulsion turbidity over time. A coalescence index (CI) was determined and used to compare emulsions stabilized with casein, whey (WPI) and soy protein isolates (SPI). CI increased when stirring rate increased. Casein produced more stable emulsions, followed by WPI and SPI. High homogenization pressure increased coalescence stability of WPI and SPI‐stabilized emulsions and decreased coalescence stability of casein‐stabilized emulsions. Microscopic examination, showed agitation of the emulsion had clearly induced formation of large oil droplets which acted as coalescence nuclei.
α‐, γ‐ and δ‐Tocopherol Effects on Chlorophyll Photosensitized Oxidation of Soybean Oil
Authors: JUNG MUN Y. , CHOE EUNOK , MIN DAVID B.
Published: August 2006

The effects of 0, 1.0, 2.0 and 4.0 (x 10−3 M) α‐, γ‐ or δ‐tocopherol on chlorophyll b photosensitized oxidation of soybean oil in methylene chloride were studied by peroxide values and headspace oxygen. As concentrations of tocopherols increased, peroxide values decreased and headspace oxygen increased (P < 0.05). At 1.0 × 10−3 M, α‐tocopherol showed highest antioxidant effect, γ‐tocopherol second and then δ‐tocopherol. α‐ and ‐γ‐Tocopherols had similar effects and δ‐tocopherol had lower effect at 2.0 × 10−3 M (P < 0.05). However, the three tocopherols were not different (P > 0.05) at 4.0 × 10−3 M. α‐Tocopherol quenched singlet oxygen to reduce the photosensitized oxidation of oil. The quenching rate constants of α‐tocopherol were 2.7 × 107M−1sec−1 by peroxide value and 2.6 × 107 M−1sec−1 by headspace oxygen.
Hexanal Formation via Lipid Oxidation as a Function of Oxygen Concentration: Measurement and Kinetics
Authors: KOELSCH C.M. , DOWNES T.W. , LABUZA T.P.
Published: August 2006

A system was developed to continuously quantify hexanal produced via lipid oxidation of oils at constant oxygen concentrations. Two kinetic models were derived from molecular mechanisms of oxidation to describe the initial (a cubic model) and accelerated (an extended model) stages of oxidation. The kinetic models illustrated the mechanistic influence of oxygen on rate constants and fit the data as well as simplistic curve fitting models. The monomolecular reaction phase showed the expected hyperbolic fit of inverse rate vs reciprocal oxygen concentration. The break point between initial and accelerated stages as function of oxygen concentration was represented by a logarithmic function.
Thermal Processes for Metal Cans Compared to Retortable Plastic Containers
Authors: LU Q. , MULVANEY S.J. , HSIEH F.
Published: August 2006

Comparison of the heating process and determination of the critical heating point was studied for homogeneous and nonhomogeneous products in 211 × 214 retortable plastic containers and metal cans. The fh, j, and Fo values for bentonite dispersions (4‐10%), were significantly different at α= 0.05 for the metal cans versus the plastic containers with metal lid oriented up or down. The slowest heating point was mathematically determined and found to be influenced by the container material and the lid orientation for the plastic containers. Results indicated the design of thermal processes in plastic containers must take into account nonsymmetrical external heat transfer due to the presence of the metal lid.
Pigment Stability Improvement in Beef Steak by Ascorbic Acid Application
Authors: MITSUMOTO M. , CASSENS R.G. , SCHAEFER D.M. , SCHELLER K.K.
Published: August 2006

The effect on meat color of spreading a vitamin C solution on the surface of fresh beef longjssimus was studied during 16 days of illuminated display at 4°C. The meat treated with 10% vitamin C solution at 0.1 mL solution to 20g meat had lower metmyoglobin and higher oxymyoglobin than the control after 4 days of display. Vitamin C treatment delayed metmyoglobin formation for 3 days compared to the control.
Processing Characteristics of Pork as Influenced by Porcine Somatotropin (pST) Administration to Growing Finishing Swine
Authors: HALLORAN JAMES D. , ROGERS R.W. , MIKEL W.B. , ALTHEN T.G.
Published: August 2006

Twenty‐four barrows were randomly divided into two groups. One group received daily subcutaneous injections of 70 μg porcine somatotropin (pST)/kg body weight (BW) from 40 kg BW until slaughter (108 kg BW). The second group received daily equal volume injections of a sterile bicarbonate buffer, pH 9.4. The left side hams, loins, and bellies obtained conventionally, were processed into typical cured products. Warner‐Bratzler shear values, % protein, % fat and visual fat to lean ratio were increased by pST (P<0.05). The treated products had characteristics beneficial to both processors and consumers.
Replacement of Beef Fat with Partially Hydrogenated Plant Oil in Lean Ground Beef Patties
Authors: LIU M.N. , HUFFMAN D.L. , EGBERT W.R.
Published: August 2006

Partially hydrogenated plant oils (corn, cottonseed, palm, peanut and soybean) were substituted (in part) for beef fat in lean (10% fat) ground beef patties to improve nutrient content of ground beef. Effects of such addition on composition and consumer acceptability were evaluated. Addition of hydrogenated plant oils had little effect on composition of raw or cooked patties. Those containing hydrogenated corn or palm oil were not different (P>0.05) from all‐beef patties in cooking loss or overall acceptability. Therefore substitution of hydrogenated oils for beef fat in production of lean ground beef patties may be feasible.
Determination of Sorbic Acid in Raw Beef: An Improved Procedure
Authors: CAMPOS CARMEN , GERSCHENSON LIA N. , ALZAMORA STELLA M. , CHIRIFE JORGE
Published: August 2006

Various analytical methods for sorbic acid determination based on removal of the preservative by distillation or ether extraction, followed by UV or colorimetric analysis gave relatively poor recoveries (52–84%) when applied to raw beef. An improved procedure was developed based on disintegration and dispersion of beef with sand prior to steam distillation and colorimetric determination. This resulted in almost 100% recovery of sorbate, attributed to more efficient extraction because of increased surface area.
Process Parameter Effects on Particle Residence Time in a Vertical Scraped Surface Heat Exchanger
Authors: LEE JUN H. , SINGH RAKESH K.
Published: August 2006

Residence times of 1.0‐2.0 cm potato cubes with 0.4‐1.2% aqueous solutions of sodium carboxymethyl cellulose flowing at 453‐599 mli sec were investigated in a vertical scraped surface heat exchanger rotating at 60 160 rpm. Minimum and maximum normalized particle residence times (NPRTs) standard deviation of mean NPRTs, and characteristic parameter for tanks‐in‐series models were not significantly affected by particle concentration. Mean NPRT for 40% particle concentration was significantly higher than those of single particle ‐ 20% particle concentrations. Mean NPRTs were significantly influenced by process parameters and 2‐way interactions.
Thermal Inactivation Kinetics of Food‐borne Yeasts
Authors: TÖRÖK T. , KING A.D.
Published: August 2006

The thermal inactivation kinetics of three food‐borne yeasts from heat‐treated products‐two Sacc. cerevisiae and one Zygosacc. rouxii‐hsve been determined. Thermal treatment and evaluation of results were carried out according to the dynamic heat destruction method. Results for 0.5% (w/w) glucose as heating medium expressed in D55 values were 1.05, 2.67 and 0.16 min, respectively. The respective z values were 4.00, 6.23 and 5.55°C. The apparent activation energy for heat destruction calculated from the Arrhenius plot for the three yeasts were 5.05*105, 3.61*105 and 3.60*105 Jmol‐1. Applying Eyring's theory of absolute reaction rates for thermal destruction, values for enthalpy and entropy of activation could be calculated.
Destructive Effect of Aspartame on Ascorbic Acid in Cu‐catalyzed Solutions
Authors: HSIEH Y. P. , HARRIS N. D.
Published: August 2006

The effect of aspartame on the early stage of ascorbic acid oxidation in solutions was studied by measuring ascorbic acid retention in an open system at 30°C and the oxygen uptake in a closed system at 33°C. Comparisons were also made between aspartame (0.06% and 0.12%) and sucrose (10% and 20%) in Cu‐catalyzed and noncatalyzed solutions at 30°C. Copper activity in aspartame solution was measured by using a cupric ion selective electrode. Aspartame increased the rate of ascorbic acid oxidation in all tested solutions. In the presence of copper the oxidation rate of ascorbic acid was significantly higher in aspartame solutions than in sucrose solutions despite the fact that aspartame showed Cu‐complex capacity in solution.
Thermal Inactivation of Asparagus Lipoxygenase and Peroxidase
Authors: GANTHAVORN C. , NAGEL C. W. , POWERS J. R.
Published: August 2006

Thermal stability of lipoxygenase (LOX) and peroxidase (POD) in fresh asparagus tips and partially purified asparagus LOX and POD were compared. In all cases, heating at 50, 60 and 70°C resulted in higher percentages of residual LOX activity than POD activity. Inactivation of LOX followed first order kinetics while inactivation of POD followed a biphasic curve. Activation energies for thermal denaturation of the partially purified enzymes were 47.5 kcal/mol for LOX and 41.9 kcal/mol for POD.
Effects of Short‐term Exposure to Low O2 and High CO2 Atmospheres on Quality Attributes of Strawberries
Authors: KE DANGYANG , GOLDSTEIN LINDA , O'MAHONY MICHAEL , KADER ADEL A.
Published: August 2006

Strawberries (Fragaria ananassa Duch., cv. ‘Selva') were stored 10 days in 1.0%, 0.5%, or 0.25% 02 or air + 20% CO2; or 6 days in air + 50% or 80% CO2 at 0 or 5°C without detrimental effects on quality. Decay and softening were reduced by treatments. An untrained taste panel, under ordinary eating conditions, did not consistently differentiate ‘Pajaro’ strawberries kept in 0.25% 02 from those stored in air. A trained taste panel, under controlled conditions, perceived slight off‐flavor in ‘G3’ strawberries kept in 0.25% or 0% 02. This correlated with ethanol, ethyl acetate, and acetaldehyde in juice. The 50% or 80% CO2 treatments caused injury after 8 to 10 days, while 20% CO2 treatments did not. All high CO2 treatments caused increase in pH of juice.
Effect of Preparation Procedures and Storage Parameters on Quality Retention of Salad‐cut Lettuce
Authors: BOLIN H.R. , HUXSOLL C.C.
Published: August 2006

Piece‐size reduction, which is required in preparing lettuce for salads, shortens storage life of cut lettuce as compared to uncut head lettuce. Cellular fluids, released during cutting, are removed by rinsing with water, followed by centrifugation to remove added surface moisture. Extended centrifugation can cause desiccation of product, which may be beneficial under certain conditions. Other methods of water removal, such as blotting or forced air did not seem practical. During storage green pigmentation decreased in salad‐cut lettuce. Optimum cold storage was obtained by packaging the cut‐lettuce in pouches that had been slightly evacuated and contained a small amount of carbon monoxide.
Influence of Drying Methods on Volatile Sulfur Constituents of Caucas (Allium victorialis L.)
Authors: WIJAYA C. HANNY , NISHIMURA HIROYUKI , TANAKA TSUNEO , MIZUTANI JUNYA
Published: August 2006

The effects of freeze‐drying, hot air, and vacuum far infrared‐drying on caucas (Allium victorialis L.) flavor was studied. The GC and GC‐MS characterization of volatiles from dried caucas powders revealed the main flavor components; disulfides and trisulfides, as well as the antithrombotic substances; vinyldithiins, remained in all products. Vi‐nyldithiins were isolated and subsequently confirmed by IR, NMR and Mass Spectrometry. Rehydration of the dried powders increased measurable volatile compounds, which were produced enzymatically. Increased‐storage time decreased measurable volatiles in freeze‐dried and hot air‐dried caucas powders while the volatile profile remained unchanged.
Supercritical CO2 Extraction of Annatto (Bixa orellana) Pigments and Some Characteristics of the Color Extracts
Authors: CHAO ROY R. , MULVANEY STEVEN J. , SANSON DALE R. , HSIEH FU‐HUNG , TEMPESTA MICHAEL S.
Published: August 2006

Supercritical CO2 (SC‐CO2) was used to extract natural food colors from Annatto (Bixa orellana) seeds with different pressures and temperatures. Results from the reverse thin‐layer chromatographic separation and GC/MS revealed that SC‐CO2 extracts were composed mainly of bixin, geranylgeraniol and norbixin. Differences in absolute values of solubility parameters (SPD) between these main compounds and SC‐CO2 indicated bixin was more easily extracted than norbixin under conditions used. A higher yield of total pigments was obtained at extraction pressure above 310 bar than at 210 bar and 50°C.
Sodium Dodecyl Sulfate and Sulfite Improve Some Functional Properties of Soy Protein Concentrates
Authors: ARCE C.B. , PILOSOF A.M.R. , BARTHOLOMAI G.B.
Published: August 2006

The effects of sodium dodecyl sulfate (SDS) and sodium sulfite were studied on dispersibility, water and oil absorption of soy protein concentrates from toasted soy flours. Dispersibility was improved from 6.2% to 65% by 0.5% SDS, 0.25% sodium sulfite at pH6, and 60°C. Water absorption was improved from 5.5 to 7 mL water/g concentrate by 0.5% SDS at pH 6 at 20°C. Oil absorption was improved from 4.1 to 5.9 mL oil/g concentrate by 0.5% SDS, 0.25% sodium sulfite at pH 6 and 20°C.
Moisture Sorption Hysteresis in Kudzu Starch and Sweet Potato Starch
Authors: BOKI K. , OHNO S.
Published: August 2006

Moisture sorption hysteresis loops of kudzu starch and sweet potato starch were investigated to help understand the nature of the adsorption‐desorption process. The second adsorption isotherms were above the first adsorption isotherms for kudzu starch and sweet potato starch preheated to 110°C. This was explained as an increase in the number of hydrophilic sites due to rupturing of hydrogen bonds. The hysteresis loop for kudzu starch was greater than that for sweet potato starch. This was interpreted as a difference in mesopore volume.
3‐Chloro‐1,2‐Propanediol Derived Amino Alcohol in Protein Hydrolysates
Authors: VELÍ'Scar;EK J. , DAVÍDEK T. , DAVIDEK J. , HAMBURG A.
Published: August 2006

In model aqueous solutions containing 3‐chIoro‐l,2‐propanediol (arising by the interaction of hydrochloric acid with lipids in protein hydrolysate and ammonia, 3‐amino‐1,2‐propanediol was found as the main reaction product together with smaller amounts of glycerol. The reaction mechanism of formation of these two compounds was outlined and discussed as well as the possibilities of formation of some other amino analogues of glycerol chlorohydrins. 3‐Amino‐1,2‐pro‐panediol was also identified in commercially available seasonings (hydrolyzed vegetable protein) being present in concentrations of 30 mg kg‐1.
3‐Chloro‐1,2‐propanediol Derived Amino Acids in Protein Hydrolysates
Authors: VELÍŠEK J. , DAVÍDEK T. , DAVÍDEK J. , KUBELKA V. , VÍDEN I.
Published: August 2006

Glycerol monochlorohydrin, (3‐chloro‐1,2‐propanediol), which occurs in chemical hydrolysates of proteins, reacted with amino acids in model aqueous solutions to form the corresponding glycerylamino acids, i.e. N‐(2,3‐dihydroxypropyl)‐amino acids. N‐(2,3‐dihydroxy‐propyl)‐derivatives of 15 amino acids were prepared and analyzed by gas chromatography and gas chromatography‐mass spectrometry. No N‐(2,3‐dihydroxypropyl)‐amino acid was detected in a freshly produced commercial soybean hydrolysate. Amounts up to ∼1 mg‐kg‐1 of N‐(2,3‐dihyproxypropyl)‐serine and ‐threonine were found in a stored hydrolysate. Higher amounts of N‐(2,3‐dihydroxypropyl)‐amino acids (up to about 10 mg‐kg‐1) were found in the alkaline treated and with 3‐chloro‐1,2‐propanediol fortified hydrolysate. N‐(2,3‐dihydroxypropyl)‐amino acids represent a new class of amino acids not previously reported in foodstuffs.
Influence of Sodium, Potassium and Magnesium Chloride on Thermal Properties of Beef Muscle
Authors: BARBUT S. , FINDLAY C.J.
Published: August 2006

Sodium, potassium and magnesium chloride, at 1.25, 2.50 and 5.00%, were studied using differential scanning calorimetry. Increasing NaCl resulted in decrease in myosin transition temperature (T1, first transition) and enthalpy (H1); both showed significant (P<0.05) linear response. The sarcoplasmic proteins and collagen denaturation temperature (T2, second transition) increased significantly over the control when 1.25% NaCl was added, but were the same as control when 2.5% and 5.0% were used. Actin denaturation temperature (T3, third transition) tended to increase when NaCl was added, but enthalpy decreased. Potassium chloride showed similar effects to NaCl on T1, T2, H1 and H3. Increasing magnesium chloride had much more pronounced effect on decreasing second enthalpy compared to the monovalent salts. At 5% MgCl2 T1 increased significantly.
Supercritical CO2 Conditions Affecting Extraction of Lipid and Cholesterol from Ground Beef
Authors: CHAO R.R. , MULVANEY S.J. , BAILEY M.E. , FERNANDO L.N.
Published: August 2006

Ground beef was extracted by supercritical CO2 (SC‐CO2) with pressure ranging from 103‐310 bar at 30‐50°C. Higher pressure was needed to increase yield of extracted lipid. The profile of cholesterol content for the fractionated lipid extracted at 172 bar or 310 bar was generally lower in the initial stage of extraction and increased with CO2 used. DSC thermograms indicated that, depending upon extraction conditions, the distribution of lipid components of fractionated samples either shifted toward higher melting temperatures or concentrated those lipids melting between 5‐25°C.
Protein Extractability and Thermally Induced Gelation Properties of Myofibrils Isolated from Pre‐ and Postrigor Chicken Muscles
Authors: XIONG Y.L , BREKKE C.J.
Published: August 2006

Purified chicken myofibrils were suspended in 0.6M NaCl at various pH values to study gelation properties of the myofibrils. Postrigor breast myofibrils showed a greater protein extractability and gel strength than prerigor breast myofibrils, but the reverse was found for leg myofibrils. Salt‐soluble protein was least extractable at pH 5.50 for both breast and leg myofibrils. The pH for optimum gelation, indicated by increased penetration force, was 6.00 for breast and 5.50 for leg myofibrils. Heating at 1°C/min from 20 to 70°C produced stronger breast but weaker leg myofibril gels than isothermal heating at 70°C for 20 min. Muscle rigor state showed a greater effect on protein extractability and gel strength for breast myofibrils than for leg myofibrils.
Bisulfite Atlernatives in Processing Abrasion‐Peeled Russet Burbank Potatoes
Authors: SANTERRE CHARLES R. , LEACH TODD F. , CASH JERRY N.
Published: August 2006

Whole, abrasion‐pecled Russet Burbank potatoes were dipped in a solution containing 3% D‐araboascorbic acid (erythorbic acid), 0.25% sodium acid pyrophosphate and 2% sodium chloride or water. They were drained and packed in 0.2% citric acid, 0.2% sorbic acid and 0.25% calcium chloride or water, sealed in plastic bags and stored at 3.8°C. Potatoes packed in the citric acid mixtures maintained a lower microbial load after 6 days storage when compared to bisulfite‐treated or water‐dipped potatoes. All potatoes maintained acceptable color through 18 days storage. Treatments did not alter shear force measurements of raw, peeled potatoes or perceived flavor and texture of cooked, mashed potatoes.
Volatile Compounds from the Mesocarp of Persimmons
Authors: HORVAT R. J. , SENTER S. D. , CHAPMAN G. W. , PAYNE J. A.
Published: August 2006

Steam volatile fractions from astringent and nonastringent persimmons (Diospyros kaki L.) and the native American persimmon (D. virginiana L.) were analyzed by GC and GC/MS. Bomyl acetate and (E)‐2‐hexenal were major components from all cultivars. Minor constituents included (E)‐2‐hexenol, phenylacetaldehyde, phenylethyl acetate, borneol, benzothiazole, neryl acetate, palmitic acid and two saturated normal hydrocarbons (C23H48 and C25H52). From threshold values and concentrations, (E)‐2‐hexenal and bornyl acetate probably are major contributors of persimmon aroma.
Clostridium botulinum Growth and Toxigenesis in Shelf‐Stable Noodles
Authors: IKAWA J.Y.
Published: August 2006

Unacidified and acidified noodles were inoculated with a composite of C. botulinum types A and B spores. Noodles were cooked, packaged in oxygen‐permeable polypropylene bags, steamed, cooled, then stored aerobically at 7 or 23°C, or anaerobically at 30°C. Toxin did not develop in any aerobically stored samples at pH ±4.5. Toxin developed in samples with pH >5.0, stored aerobically and anaerobically. In addition, toxin was detected in one anaerobically incubated acidified unit where pH had been increased by microbial growth. Proper acidification of product prevented toxic growth of C. botulinum.
Simultaneous Determination of Sugars and Organic Acids in Cheddar Cheese by High‐Performance Liquid Chromatography
Authors: BOUZAS JORGE , KANTT CARLOS A. , BODYFELT FLOYD , TORRES J. ANTONIO
Published: August 2006

In a simple, rapid isocratic HPLC method sugars and organic acids were separated on an Aminex HPX‐87 column in the H+ form and detected using ultraviolet and refractive index detectors in series. Sugars (lactose, glucose and galactose) and acids (orotic, citric, pyruvic, lactic, uric, formic, acetic, propionic, butyric and hippuric) were identified by retention times. This method affords a simple technique for monitoring starter culture activity and following quality changes during cheese maturation.
Assessment of the Sensory Characteristics of Meat Patties
Authors: BEILKEN S.L. , EADIE L.M. , GRIFFITHS I. , JONES P.N. , HARRIS P.V.
Published: August 2006

The use of two different methods for determining sensory profiles for texture of meat patties was investigated and compared with consumer ratings. The individual sensory profiles developed in free‐choice profiling were analyzed using generalized Procrustes and principal components analysis techniques and converted by discussion to a single consensus profile. Using three components of the principal components analysis the free‐choice profile accounted for 88.2% of the total variance in texture and the consensus profile for more than 90%. The first components related mostly to mechanical strength attributes and the second to greasiness and juiciness. Both sensory profiles were shown, using preference mapping techniques, to be good indicators of consumer acceptability.
Mitochondrial Activity and Beef Muscle Color Stability
Authors: LANARI M.C. , CASSENS R.G.
Published: August 2006

Concentration, oxygen consumption rate (OCR), oxygen consumption rate/g meat (OCRM) and metmyoglobin reducing activity (MRA) of muscle mitochondria were determined for beef longissimus dorsi and gluteus medius muscles of Holstein and crossbred steers which differed in color stability. OCR and OCRM decreased but no significant changes were observed in MRA during postmortem storage time. Significant effects of muscle and breed type on OCR, OCRM, and MRA were observed. Muscles and breeds of lower color stability had the highest levels of OCR, OCRM, and MRA. Differences in OCR of muscle mitochondria may be a contributing factor in the effects of muscle and breed on the rate of discoloration.
Isolation of Yersinia enterocolitica and Related Species from Red Meat and Milk
Authors: IBRAHIM A. , RAE I.C. MAC
Published: August 2006

A total of 150 samples, 50 each of beef, lamb and pork from 10 local retail stores in the Brisbane metropolitan area and 50 pasteurized and 150 raw bovine bulk milk tank samples obtained from Queensland United Foods (QUF), were examined for the presence of Yersinia spp. over 1 yr. Two isolation protocols were used to recover the organism with subsequent biochemical and serological identification. A total of 114 isolates, consisting of Y. enterocolitica (23,12,15,40), Y. intermedia (0,3,5,1), Y. frederiksenii (4,1,0,10) were obtained from beef, lamb, pork, and milk, respectively. No pasteurized milk samples were positive for the organism. None of the isolated strains was found to harbor the virulence plasmid as indicated by the crystal violet‐binding assay.
Water Associated with Whey Protein Investigated by Pulsed NMR
Authors: PADUA GRACIELA W. , RICHARDSON SHELLY J. , STEINBERG MARVIN P.
Published: August 2006

Proton longitudinal relaxation rates were determined for whey protein powders and suspensions of solids concentration between 0.01 and 2.0 g solids/g water. Data showed three hydration regions. The relationship between relaxation rate and solids content was investigated for each region. The two‐state model with fast exchange was applied to the dilute suspensions and the high‐solids regions. This allowed identification of polymer water and free water states in dilute suspensions and also identification of polymer water and capillary water in high‐solids preparations. For intermediate‐solids mixtures the two‐state model was extended to three water states: polymer, capillary and free. These models enabled calculation of the amount of each water state associated with whey protein at a given moisture content.
Thermal Degradation of Paralytic Shellfish Poison
Authors: NAGASHIMA YUJI , NOGUCHI TAMAO , TANAKA MUNEHIKO , HASHIMOTO KANEHISA
Published: August 2006

Components of paralytic shellfish poison (PSP) were heated under various conditions, and examined for changes in toxicity and in HPLC and TLC behaviors. The thermal degradation of PSP components progressed as a first order reaction, at different rates depending upon component and temperature. A mixture of gonyautoxin 2 and gonyautoxin 3 when dissolved in water and heated at 100°, 110°, and 120°C (180 min) retained 39, 17, and less than 3%, respectively, of initial toxicity. A mixture of gonyautoxin 1 and gonyautoxin 4 was more therrnolabile; i.e. it retained little toxicity when heated at 120°C for 60 min. HPLC and TLC analyses demonstrated that heating under those conditions converted PSP components into other substances.
Ethylene Absorbent to Maintain Quality of Lightly Processed Fruits and Vegetables
Authors: ABE KAZUHIRO , WATADA ALLEY E.
Published: August 2006

Ethylene had an undesirable effect on the quality of kiwifruits, bananas, broccoli, and spinach leaves that were prepared and stored as lightly processed products. A 2.or 20 ppm ethylene treatment hastened the softening of the pulp of kiwifruits and bananas held at 20°C. Use of charcoal with palladium chloride, as ethylene absorbent, prevented the accumulation of the ethylene and was effective in reducing the rate of softening in kiwifruits and bananas and of chlorophyll loss in spinach leaves, but not in broccoli.
Equilibrium Water Content and the State of Water in Dehydrated White Cabbage
Authors: PÄÄKKÖNEN KIRSTI , PLIT LIISA
Published: August 2006

The water sorption isotherms for freeze‐dried cabbage were determined at 15°C and 23°C, and the state of the water was studied using differential scanning calorimetry (DSC). The water sorption capacity of the freeze‐dried cabbage depended on the temperature. The effects of free sugars were clear in both adsorption and desorption. The thermal behavior of freeze‐dried cabbage was highly moisture dependent. In the capillary condensation range (>0.9 aw) solution of low molecular components of the freeze‐dried cabbage affected its freezing behavior.
Calcium Sulfate Concentration Influence on Yield and Quality of Tofu From Five Soybean Varieties
Authors: SUN NONG , BREENE WILLIAM M.
Published: August 2006

A mini‐process is described for making tofu from 50‐g quantities of soybeans. It was used to compare yield and quality among 5 Minnesota grown varieties (Vinton, Corsoy, Hardin, Stine 2510, Stine 2810) and to determine optimum concentration of the coagulant, CaSO4. Product yield (wet basis), solids recovery, protein recovery and textural quality (Texture Profile Analysis hardness and fracturability) were optimal at 0.02 N CaSO4 for all 5 varieties. Negative correlations were found between CaSO4 concentration and both yield (r =− 0.90 to 1.00) and protein recovery (r =− 0.96 to 1.00) for all varieties.
Aciduric, pH‐Elevating Bacillus which Cause Noneffervescent Spoilage of Underprocessed Tomatoes
Authors: AL DUJAILI JAMEEL , ANDERSON ROBERT E.
Published: August 2006

In the preliminary phase of this study, a selective isolation medium was developed. Using the new medium, 24 strains of Bacillus Spp. that elevate tomato juice pH were isolated from garden soil or natural vegetative materials. Two jars of home‐canned, water‐bathed tomatoes contained sporeformers which produced noneffervescent spoilage. All strains were morphologically and physiologically different from 2 flat‐sour strains of B. coagulans and B. licheniformis strains, but similar to a previous isolate from home‐canned, spoiled green beans that elevated pH. The new medium may have future applications in isolation and enumeration of other acidurics including yeast‐like microorganisms.
Low Dose Irradiation Influence on Yield and Quality of Fruit Juice
Authors: MITCHELL GREGORY E. , ISAACS A. ROBERT , WILLIAMS DAVID J. , McLAUCHLAN RICHARD L. , NOTTINGHAM STEPHEN M. , HAMMERTON KERRIE
Published: August 2006

Granny Smith apples, Valencia oranges, and Pearlette grapes grown in Queensland, Australia were irradiated at 0, 75, 300 and 600 Gy. Following irradiation, juice was extracted and analysed for quality and compositional changes. Irradiation treatment significantly (p<0.05) decreased yield of apple juice (by 6.3% w/w at 600 Gy) and grape juice (by 4.8% w/w at 600 Gy) but did not significantly (p>0.05) affect yield of orange juice (OJ). Acceptability significantly (p<0.05) decreased in OJ after 600 Gy treatment. Other changes in quality and composition were minimal. Juice from irradiated apples and oranges stored at 5°C for 8 wk showed similar results.
Filter, Fourier Transform Infrared, and Areometry, for Following Alcoholic Fermentation in Wines
Authors: DAVENEL A. , GRENIER P. , FOCH B. , BOUVIER J.C. , VERLAQUE P. , POURCIN J.
Published: August 2006

Areometry, filter near infrared spectrometry (FIR), and Fourier transform near infrared spectrometry (FTIR), have been compared for following total sugar and ethanol during fermentations. Standard errors of calibration (SEC) and prediction (SEP) have been estimated, respectively, with 4 and 2 fermentations, using as reference sugar and ethanol enzymatic analysis. With the first 4 fermentations, the least rectangles method was applied for a more thorough comparison between FIR, FTIR, and areometry. FIR was more complex and more accurate than density measurement, and less complex, but as accurate as FTIR spectrometry. Small SEP can be achieved with FIR spectrometry: 2.5 g/L for total sugars and 0.15% (v/v) for ethanol.
Degradation Kinetics of Chlorophylls and Chlorophyllides
Authors: CANJURA FATIMA L. , SCHWARTZ STEVEN J. , NUNES RAUL V.
Published: August 2006

Thermal degradation of chlorophylls and chlorophyllides in spinach puree was studied from 100 to 145°C (2–25 min) for chlorophylls and from 80 to 115°C (2.5–39 min) for chlorophyllides. The derivatives formed were: pheophorbides, pyropheophorbides, pheophytins and pyropheophytins. Degradation kinetics of chlorophylls and chlorophyllides followed a first‐order kinetic model. Reaction rate data showed that the a form of both chlorophylls and chlorophyllides degraded more rapidly than the b form. Chlorophyllides were less stable than chlorophylls. Activation energies ranged from 15.0 to 22.8 Kcal/mol. A kinetic compensation effect was observed for both chlorophylls and chlorophyllides with an isokinetic temperature of 160.8°C. The relative stability of these compounds suggests that methods to maximize chlorophyllides would not be effective for improving green color stability.
Ascorbyl Palmitate Efficacy in Enhancing the Accelerated Storage Stability of Canola Oil
Authors: MCMULLEN L.M , HAWRYSH Z.J. , LIN C. , TOKARSKA B.
Published: August 2006

The effect of various levels of ascorbyl palmitate (AP) and of butylated hydroxyanisole/toluene (BHA/BHT) on the accelerated storage stability of canola oils was determined by sensory, gas liquid chromatographic (GLC) and chemical evaluations. In Schaal oven tests (65°C, 0–16 days), chemical, GLC and trained sensory panel data indicated that 200 ppm AP retarded autoxidation in stored canola oils. Monoglyceride citrate (MGC) addition to oils containing 200 ppm AP did not enhance oil stability. Fluorescent light tests (7500 lux, 24°C, 0–24 hr) showed that 200 ppm AP, with or without MGC, had a limited effect in protecting canola oil from photooxidation. BHA/ BHT, at 100 ppm each, with MGC, did not improve canola oil stability.
Extraction of Annatto Seed Pigment by Supercritical Carbon Dioxide
Authors: DEGNAN A.J. , VON ELBE J.H. , HARTEL R.W.
Published: August 2006

Operating pressures ranged 3000–7000 psi and temperatures 40–55°C. Maximum solubility of pure bixin was 0.003 and of annatto seed pigment 0.26 mg/g CO2. Analyses of annatto seed pigment from supercritical carbon dioxide extractions showed only α‐and β‐bixin present. Only bixin was extracted from mixed samples consisting of bixin and norbixin. No thermal degradation product was detected in samples extracted within the temperature range we used. Increased temperature resulted in increased pigment/g CO2 at all pressures. Isothermal increases in pressure did not increase pigment/g CO2. Efficiency of annatto pigment extraction was increased in the presence of an oil.
Water Retention Capacity and Viscosity Effect of Powdered Cellulose
Authors: ANG JIT F.
Published: August 2006

Powdered cellulose is a natural beta‐l,4‐glucan polymer. It is 99% total dietary fiber (dwb) and has many uses as a low‐calorie food ingredient. Depending on its fiber length, cellulose can retain 3.5 to 10 times its weight in water. Temperature and pH exerted small effects on water rentention capacity. A powdered cellulose with a 110‐micron fiber length significantly increased viscosity. Its ability to increase viscosity was further, magnified in solutions containing low amounts of stabilizers. This fiber may act synergistically with other stabilizers to increase viscosity.
Rheological Changes in Oatmeal Suspensions During Heat Treatment
Authors: JANSSON KATARINA WIKSTRÖM , LINDAHL LENNART
Published: August 2006

Two amylases from fungal and bacterial source were added to oatmeal suspensions in concentrations varying from 0.0125 to 0.64%. Changes in viscosity, phase angle and elastic modulus during heating were followed together with sedimentation and flow properties. The complete pasting behavior could be followed without sedimentation problems. The hydrocolloidal properties of β‐glucans appeared to be important. The bacteria/enzyme reduced peak viscosity much more rapidly than the Fungamyl enzyme at low concentrations. The flow properties of a Fungamyl treated oat meal suspension with the peak viscosity reduced > 90% were pseudoplastic.
Viability and Performance of Pure Yeast Strains in Frozen Wheat Dough
Authors: BÁGUENA R. , SORIANO M.D. , MARTÍNEZ‐ANAYA M.A. , DE BARBER C. BENEDITO
Published: August 2006

Freezing and subsequent storage of wheat doughs containing Saccharomyces cerevisiae, S. fructuum or Candida boidinii after undergoing a bulk fermentation step, reduced the viability of yeasts, depending on the species. Freezing and storage of doughs without bulk fermentation had no effect on viability. Gassing power was affected most by frozen storage, depending on storage time and species. Changes in acidification capability were small, and only significant for total titratable acidity. Changes in sugars and leavening were closely related. Results showed that the use of less active yeast species (S. fructuum), with high freezing tolerance in frozen dough processes would be of practical interest.
Simultaneous Heat Processing of High‐ and Low‐Acid Foods in Semirigid Containers—A Theoretical Analysis
Authors: HAYAKAWA KAN‐ICHI , WANG JIANJUN , GILBERT SEYMOUR G.
Published: August 2006

A one meal‐set of military ration consists of heat sterilized, high‐ and low‐acid foods in semirigid containers. These foods are processed separately because of large differences in lethality requirements. We examined the feasibility of simultaneously processing a meal‐set consisting of chili con came, white rice, and sliced peach in syrup to minimize costs. Simultaneous processing was not possible by adjusting initial temperaturès according to computer‐simulation using food temperature data collected experimentally. However, it was possible when the container for peaches was insulated properly with expanded polystyrene. Proper insulation thickness was slightly dependent on z value of the target factor.
Membrane Reactor for Enzymic Deamidation of Food Proteins
Authors: HAMADA J.S.
Published: August 2006

A soy protein hydrolysate was deamidated with peptidoglutaminase (PGase) retained within a 30kd spiral membrane. Reactor was operated at 30°C and 6.5 L/m2/hr flux in recycle mode to 60% conversion, then in diafiltration mode for 2 hr. Time course, predicted by a Michaelis‐Menten equation integrated for mixed zero‐ and first‐order kinetics with the corrections for the ultrafiltration (UF) interactions, matched that measured experimentally. The equation could be used to predict the potential activity and performance of PGase in UF reactors to achieve control of reactions for the optimal enzymic process. At the end of the run, 96% conversion and 99% of PGase were obtained. This method has the potential of being scaled‐up for the production of enzyme‐free deamidated proteins.
Lactococcus Genus: A selective and Differential Agar Medium
Authors: AL‐ZOREKY N. , SANDINE W.E.
Published: August 2006

An agar medium (Alsan), was selective for Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. lactis biovar. diacetylactis. The former developed white or yellow colonies; the latter gave blue‐green or blue colonies. Eleven strains of L. lactis subsp. cremoris did not grow in this medium. The medium contained phenylethanol agar, lactose, glycine anhydride, lithium chloride and trimethoprim. In comparison with M17 medium, Alsan was not significantly different (P > 0.05) in recovering either bacterium. Furthermore, the medium inhibited the common food genera Pseudomonas, Escherichia, Leuconostoc, Enterococcus and Lactobacillus. Bacteriophage plaque sizes of 0.4–0.5 cm were demonstrated on the medium using a lactococcal bacteriophage.
Ultrafiltration for Recovery and Reuse of Peptidoglutaminase in Protein Deamidation
Authors: HAMADA J.S.
Published: August 2006

Ultrafiltration (UF) of B. circulans cell extract using a 100kd hollow‐fiber membrane had no effect on peptidoglutaminase (PGase) activity and allowed 34 and 26% of PGases I and II to permeate. UF, with 30kd spiral membrane, slightly increased PGase activity in retentate but no activity was detected in permeate. Retentate was used to sequentially deamidate four batches of a soy protein hydrolysate at 30°C for 2 hr, then PGase was recovered by UF. The 100kd membrane resulted in substantial PGase loss in sequential tests due to permeation and inactivation. A 100% conversion and 97% of PGase were obtained after tests with the 30 kd membrane. Multiple recovery and use of PGase by a suitable membrane is possible.
Production of Extracellular β‐Glucosidase and α‐Galactosidase during Fungal Growth on Polygalacturonate
Authors: McKAY A.M.
Published: August 2006

Filamentous fungi (Aspergillus oryzae, Scopulariopsis sp., and Penicillium brevicompactum) and yeast‐like fungi (Aureobasidium pullulans) were induced to produce extracellular β‐D‐glucosidase (β‐D‐glucosidase glucohydrolase, EC 3.2.1.21) and α‐D‐galactosidase (α‐D‐galactoside galactohydrolase, EC 3.2.1.22) by polygalacturonate in the growth medium. These extracellular enzymes were not produced during growth of the microorganisms on cellobiose or melibiose.
2‐(Hydroxymethyl)‐N‐nitrosothiazolidine‐4‐carboxylic Acid in Smoked Meats and Bacon and Conversion to 2‐(Hydroxymethyl)‐N‐Nitrosothiazolidine During High‐Heat Cooking
Authors: SEN NRISINHA P. , BADDOO PHILANDER A. , SEAMAN STEPHEN W. , WEBER DORCAS
Published: August 2006

Concentrations of 2‐(hydroxymethyl)‐N‐nitrosothiazolidine‐4‐carbox‐ylic acid (HMNTCA) in a variety of smoked meats and bacon were determined by a newly developed method based on derivatization of HMNTCA with diazomethane and analysis by high performance liquid chromatography‐thermal energy analyzer. Of samples analyzed, 4/8 raw bacon, 6/8 fried bacon, and 7/14 miscellaneous cured meat products contained 10–540 ppb of HMNTCA. Evidence suggested 2‐(hydroxyrnethyl)‐N‐nitrosofhiazolidine in fried bacon likely originated by heat‐induced decarboxylation of HMNTCA. Identity of HMNTCA in selected samples was confirmed by mass spectrometry.
Emulsified Milkfat Effects on Rheology of Acid‐Induced Milk Gels
Authors: XIONG YOULING L. , AGUILERA JOSE M. , KINSELLA JOHN E.
Published: August 2006

Reconstituted skim milk formed by a gel by acidification to < pH 5.2 and heating to 60°C. The gel compressive stress (σc) was influenced by the heating process, increased with milk‐nonfat‐solids (MNFS) and reached a maximum at pH 4.0. The addition of emulsified fat facilitated gelation, increase gel σc and shear modulus, and decreased gel deformability. At an equal fat concentration, emulsions containing small‐sized fat globules (i.e., more globules) reinforced the gels more markedly than emulsions comprised of large globules reflecting the importance of number of globules in the gels. Electron micrographs revealed crosslinkages between fat globules and casein particles in the gel network, which may have caused reinforcement of milk gels by milkfat.
Heating Characteristics of Milk Constituents in a Microwave Pasteurization System
Authors: KUDRA T. , Van, de VOORT F.R. , RAGHAVAN G.S.V. , RAMASWAMY H.S.
Published: August 2006

A continuous pasteurization system was designed using a domestic microwave oven and heating characteristics were studied on water, cream, and milk constituents. Parameters were determined as functions of flow rate and power using water ≧ 75g/min (minimum flow at full power without boiling). Operation at less than 100% caused unacceptable temperature oscillations. Cream, milks and solutions of the individual milk constituents (fat, protein and lactose), were also assessed in attempts to determine relative contributions of each. Milk heated more rapidly than water and protein was the major contributor to heating, with fat and lactose‐effects being negligible. The microwave system could heat solutions to temperatures needed for HTST pasteurization and was controlled by adjusting flow rate.
Heat‐Shocked Lactobacilli for Acceleration of Cheddar Cheese Ripening
Authors: EL ABBOUDI M. , PANDIAN S. , TREPANIER G. , SIMARD R.E. , LEE B. H.
Published: August 2006

The aim of this study was to establish adequate conditions for heat‐shocking cells of lactobacilli, to sufficiently suppress lactic acid production without damaging the proteolytic enzyme system important for cheese maturation. Three temperatures, 65, 67 and 70°C were tested, for 22 sec. The best combination for maximum retardation of lactic acid production and minimum damage to the proteolytic system was obtained by treating cells at 67°C for 22 sec. Following such treatment, lactic acid production was retarded by 24 hr, while the proteolytic enzyme system remained scarcely unchanged.
Estimation of Bacterial Quality of Cod Fillets with the Disc Flotation Method
Authors: BOISMENU D. , LEPINE F. , THIBAULT C. , GAGNON M. , CHARBONNEAU R. , DUGAS H.
Published: August 2006

Spoilage bacteria of cod fillets were desorbed off the fillet surface by ultrasonication. Catalase activity of these bacteria was determined using the disc flotation method after selective heat inactivation of the endogenous cod catalase and then correlated with the colony forming units. The method was applied to cod fillets from ten retail sources with satisfactory results.
Acid Requirement for pH Modification of Processed Foods
Authors: MCCARTHY M.J. , HEIL J.R. , KRUEGERMANN CARL , DESVIGNES DENIS
Published: August 2006

A bench‐top procedure was developed and tested for estimating the acid requirement for modifying the pH of low acid foods. Acid amounts needed to achieve desired equilibrium pH in finished products depended on total solids, protein and ash contents of foods, and on buffering capacities of acidulants and foods. Acid requirements to modify pH were calculated from titration curves. Specified equilibrium pH values were achieved within 0.08 pH unit. Effective gluconic acid diffusion (Deff) into a buffered model food was 8.3 × 10−10±1.5 × 10−10 m2sec‐1.