bluuebunny/crossref_metadata_2025 huggingface dataset:
Radiation Sensitivity and Recoverability of Listeria monocytogenes and Salmonella on 4 Lettuce Types
Authors: NIEMIRA B. A.
Published: July 2006

ABSTRACT Listeria monocytogenes or Salmonella was inoculated onto Boston, Iceberg, Green leaf, and Red leaf lettuces. Samples were γ‐irradiated, and the radiation sensitivity of the inoculated bacteria determined. Recovery of bacteria from nonirradiated leaf pieces was also measured. Although the radiation sensitivity of L. monocytogenes was not influenced by the associated lettuce type, Salmonella was significantly less sensitive on Green leaf lettuce than on Boston, Iceberg, or Red leaf lettuces. For each pathogen, the recoverability from inoculated leaf pieces was significantly different among the 4 lettuce types; the pattern of recovery of L. monocytogenes was distinct from that of Salmonella. The antimicrobial efficacy of irradiation on inoculated lettuce was influenced by relatively subtle differences between lettuce types.
Spoilage of Rested Harvested King Salmon (Oncorhynchus tshawytscha)
Authors: FLETCHER G. C. , CORRIGAN V. K. , SUMMERS G. , LEONARD M. J. , JERRETT A. R. , BLACK S. E.
Published: July 2006

ABSTRACT Laboratory‐reared king salmon were harvested using CO2 anesthetizing (CO2) or by rested harvesting techniques using AQUI‐S(tm) anesthetizing (AQUI‐S). Fish were killed by spiking, and flesh portions were stored in air packs (0°C) for 22 d. Headspace oxygen levels, sensory characteristics (raw and cooked), tensile properties, drip loss, gaping, pH, nucleotide derivatives, color, and bacterial counts were determined after 5 to 22 d of storage. All parameters except tensile properties showed significant trends with storage time. Oxygen levels were consistently lower in CO2 packs whereas, on average, drip was lower in AQUI‐S samples, and L*‐values and bacterial numbers were higher in AQUI‐S samples. Overall, harvesting effects had minimal impact on the quality parameters measured.
Analytical Method for Determination of Some Aroma Compounds on White Wines by Solid Phase Microextraction and Gas Chromatography
Authors: FERREIRA A. C. SILVA , DE PINHO P. G UEDES
Published: July 2006

ABSTRACT A method for analyzing volatiles such as alcohols (1‐octen‐3‐ol), aldehydes (trans‐trans‐2,4‐decadienal, trans‐2‐nonenal), terpenols (linalool, terpineol, and oxides), and isoprenoids (β‐damascenone, β‐ionone, 1,1,6‐trimethyl‐1,2‐dihydronaphtalen and vitispirane) on white wines using solid phase microextraction has been developed. The analytes were extracted directly from the headspace of a constant volume of wine using 7 different fibers coated with different stationary phases compared with a classic dichloromethane extract. The best extraction efficiency was obtained with a divinylbenzene/Carboxen/polydimethylsiloxane, 50/30 μm. Sample volume, time, and temperature of the extraction were optimized and the matrix effect studied. The limits of quantification varied between 0.013 and 1.81 μg/L. The r‐values for linearity studies varied between 0.9761 and 0.9999. Among the compounds measured, some are related to the aroma of young white wine, such as linalol, terpineol, β‐damascenone, whereas others, for example, 1‐octen‐3‐ol, trans‐trans‐2,4‐decadienal, trans‐2‐nonenal, 1,1,6‐trimethyl‐1,2‐dihydronaphtalene, and vitispirane, are related to evolution characteristic of white wines.
Growth Inhibition of Bacteria by Salsa Mexicana
Authors: Orozco A. , Ogura T. , Beltran‐Garcia M. J. , Kubo I.
Published: July 2006

ABSTRACT: Antimicrobial activity of salsa mexicana against Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, and Saccharomyces cerevisiae was studied. The pressed salsa juice suppressed completely the growth of E. coli, B. subtilis, and S. aureus. K. pneumoniae and B. cereus were suppressed partly but Saccharomyces cerevisiae was not suppressed at all by the juice. Three types of microbicidal or microbiostatic components have been found: (1) H+, (2) volatile compounds, and (3) non‐ionized carboxylic acids or analogous compounds. It is proposed that the supplementation of stink bugs in the salsa seen widely in the south of Mexico is used to intensify the herbal odor of the salsa.
Effects of Alcohol Type and Amounts on Conjugated Linoleic Acid Formation During Catalytic Transfer Hydrogenation of Soybean Oil
Authors: Ju J.W. , So W.S. , Kim J.H. , Bae B.J. , Choi E.N. , Kwon Y.H. , Chung I.M. , Yoon S.H. , Jung M.Y.
Published: July 2006

ABSTRACT: Effects of alcohol type and amount on formation of conjugated linoleic acids (CLAs) in soybean oil were studied during catalytic transfer hydrogenation with a nickel catalyst and an alcohol as a hydrogen donor. Identification and quantification of CLA isomers in the oil were done by 100‐m cyano‐capillary column gas chromatography. Butanol and propanol showed the highest activity for the formation of CLAs, followed by ethanol and methanol. As the amount of ethanol in the reaction system increased from 0% to 2.5%, CLA formation increased. At the level of 2.5%, CLA formation decreased. CLA compositions in soybean oils were also affected by hydrogenation time and alcohol amount. Catalytic transfer hydrogenation with alcohol has an advantage over classic hydrogenation with a gaseous hydrogen in that soybean oil, with an extremely low level of t‐C18:1 but high level of CLAs, could be produced.
Pigment Changes in Fried Dough Containing Spinach Powder During Storage in the Dark
Authors: Kim M. , Lee J. , Choe E.
Published: July 2006

ABSTRACT: Changes in chlorophyll and carotenoid contents of fried dough supplemented with spinach (Spinacia oleracea) powder were investigated during storage. Flour dough containing spinach powder was fried in soybean oil at 160 °C for 1 min and stored in a glass bottle at 60 °C incubator in the dark up to 12 d. Chlorophyll contents decreased with storage time, whereas pheophytin contents increased followed by decrease. Decomposition of chlorophyll a was faster than that of chlorophyll b. Carotenoids were decomposed during storage; however, the decomposition rate was lower than that of chlorophylls. Decrease in carotene contents with storage time was slower than that in xanthophylls.
Apple Polyphenol Oxidase Inhibitor(s) from Common Housefly (Musca Domestica L.)
Authors: Yoruk R. , Hogsette J.A. , Rolle R.S. , Marshall M.R.
Published: July 2006

ABSTRACT: A new natural apple polyphenol oxidase (PPO) inhibitor(s) from housefly (Musca domestica L.) was discovered. Crude inhibitor (s) isolated by buffer extraction, heat treatment, and dialysis from housefly pupae inhibited the activity of apple PPO up to 90% at pH values above 5.0. Inhibition was strictly pH‐dependent. The inhibitor(s) was further characterized by employing heat, freezing and thawing, irradiation, pH adjustment, and ultrafiltration studies. The potential PPO inhibitor(s) was stable to heating at 100 °C for 1 h, repeated freezing and thawing, and irradiation. The inhibitor(s) was most stable at pH around 5.0 and least stable at alkaline pH. The PPO inhibition profile of housefly during metamorphosis also was evaluated.
Characterization of Cider Brandy on the Basis of Aging Time
Authors: Madrera R. Rodriguez , Blanco Gomis D. , Alonso J.J. Mangas
Published: July 2006

ABSTRACT: To characterize cider brandies on the basis of age, chemometric techniques (principal component analysis, linear discriminant analysis, and Bayesean analysis) together with contents of volatile, furanic, and phenolic compounds were used. Significant principal components computed by a double cross‐validation procedure allowed us to visualize the structure of the database as a function of the aging time to which the cider brandies had been subjected. Feasible and robust discriminant rules were computed and validated by a cross‐validation procedure that allowed suitable classification of fresh and aged brandies, obtaining classification hits >; 90%. The most discriminant variables for characterizing cider brandies according to their aging level were as follows: ethyl caprylate > ethyl isovalerate > 1‐propanol > hexyl acetate.
Sorption Behavior of Selected Aldehyde‐scavenging Agents in Poly(ethylene terephthalate) Blends
Authors: Suloff E.C. , Marcy J.E. , Blakistone B.A. , Duncan S.E. , Long T.E. , O'Keefe S.F.
Published: July 2006

ABSTRACT: Poly(m‐xylylene adipamide) (nylon MXD6), D‐sorbitol, and a‐cyclodextrin aldehyde‐scavenging agents were blended with poly(ethylene terephthalate) and thermally pressed into films. Films were stored in an acidified aqueous model solution (pH 3.6) containing a 25 μM mixture of acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, and caproaldehyde for 1, 3, 7, and 14 d. The total amount of aldehydes sorbed by films was 2 to 10 times higher for films containing aldehyde‐scavenging agents than nonblended films. Aldehyde‐scavenging films demonstrated selective scalping, preferring smaller molecular weight aldehydes to larger aldehydes. Partition coefficients for smaller aldehydes were 3 to 6 times greater for aldehyde‐scavenging films than control film.
Growth of Probiotic and Traditional Yogurt Cultures in Milk Supplemented with Whey Protein Hydrolysate
Authors: Mccomas K.A. , Gilliland S.E.
Published: July 2006

ABSTRACT: Growth of some probiotic bacteria was significantly improved in milk supplemented with whey protein hydrolysate (WPH). However, WPH had no effect on the growth of Lactobacillus delbrueckii ssp. bulgaricus 18, L. delbrueckii ssp. bulgaricus 10442, and Streptococcus thermophilus 1. When the probiotic bacteria were grown in combination with different yogurt cultures in milk, WPH caused significant increases in growth of Bifidobacterium longum S9, L. acidophilus O16, and L. acidophilus L‐1. However, by day 28 of refrigerated storage, the populations of the probiotic cultures that had been grown in samples supplemented with WPH were similar or below those in the control samples.
Physical and Sensory Characteristics of Chiffon Cake Prepared with Erythritol as Replacement for Sucrose
Authors: Lin S‐D. , Hwang C‐F. , Yeh C‐H.
Published: July 2006

ABSTRACT: The effects of erythritol on physical and sensory characteristics of chiffon cakes were studied. The results showed that chiffon cakes prepared with 25%, 50%, 75%, and 100% replacement of sucrose with erythritol were lighter in crust and crumb and less sweet in crumbs than those with sucrose. There were no differences in the specific gravity of cake batter, volume, and moisture content between cakes prepared with sucrose or erythritol. Results from sensory evaluation also showed no significant differences in crumb color, moistness, and tenderness for any cakes.
Comparison of Antioxidant Activities of Isoflavones from Kudzu Root (Pueraria lobata Ohwi)
Authors: Jun M. , Fu H.‐Y. , Hong J. , Wan X. , Yang C.S. , Ho C.‐T.
Published: July 2006

ABSTRACT: Isoflavones and their glycosides were isolated from kudzu root, and formononetin‐7‐O‐glucoside (ononin) was identified from the plant for the first time. Among isolated compounds, the antioxidant potency of 5 major compounds was determined using (1) 2,2‐diphenyl‐1‐picrylhydrazyl free‐radical scavenging assay, (2) thiocyanate assay in the linoleic acid model system, and (3) lipoxygenase inhibition assay. The study indicates that 5 compounds act as free‐radical scavengers and inhibit both linoleic acid peroxidation and lipoxygenase activity. The 3 different assays for determining antioxidant activity revealed that activity in one test did not necessarily correlate with activity in another test. Arachidonic acid release in the intact HL‐29 cancer cell, biochanin A, showed strong inhibition of about 70%, at a concentration of 50 μ.M.
Effect of γ‐Oryzanol on the Flavor and Oxidative Stability of Refrigerated Cooked Beef
Authors: Kim J.‐S. , Suh M.‐H. , Yang C.‐B. , Lee H. G.
Published: July 2006

ABSTRACT: γ‐Oryzanol and α‐tocopherol were added to beef patties as natural antioxidants. Beef patties containing 100 ppm γ‐oryzanol had higher oxidative stability (P <0.05) during storage at 4 °C than did beef patties with other antioxidants and without antioxidant. Thiobarbituric acid‐reactive substances (TBARS) values, warmed over flavor (WOF) scores, C‐7 oxidized cholesterol derivatives (OCDs), and concentrations of both hydroperoxide and hexanal in the cooked beef containing γ‐oryzanol were significantly lower than those of other treatments (P < 0.05). All variables had similar trends during the refrigerated storage. Significant correlations were found between TBARS and C‐7 OCDs, TBARS and WOF, hydroperoxide and hexanal, and hexanal and WOF (P < 0.05).
Changes in Color and Phenolic Compounds During Oxidative Aging of Sherry White Wine
Authors: Ortega A. F. , Lopez‐Toledano A. , Mayen M. , Merida J. , Medina M.
Published: July 2006

ABSTRACT: Results show that the variables studied in this work increased to a greater extent in a 1st stage (wine exposed for 4 y to daily temperature fluctuations) than in a 2nd stage (wine held at a constant temperature of approximately 17 °C up to the 14th year). To study aging under more controlled conditions, a 2‐stage laboratory experiment was carried out (the 1st ranging from 15 to 30 °C, the 2nd at 30 °C). The results revealed an important acceleration in the aging of this type of wine. However, aroma and flavor properties were slightly affected, probably because of the higher temperature maintained during the 2nd stage.
A Survey on the Potential Mode of Inhibition for Oxalic Acid on Polyphenol Oxidase
Authors: Yoruk R. , Marshall M.R.
Published: July 2006

ABSTRACT: The potential mode of inhibition for xalic acid on polyphenol oxidase (PPO) was investigated. The extent of inhibition was influenced not only by oxalic acid concentration but also by pH. Inhibition was most prominent at pH 4.0 where complete inhibition occurred at the 4‐mM oxalic acid concentration and was less evident at higher pH values. Inhibition of PPO by oxalic acid was due to its binding with copper to form an inactive complex, and the inhibition was characterized as noncompetitive. Oxalic acid diminished the catechol‐quinone product formation, and no quinone bleaching was observed. Oxalic acid was a more potent inhibitor of PPO compared with other structurally related acids.
Modeling Thermal and Mechanical Effects on Retention of Thiamin in Extruded Foods
Authors: Cha J.Y. , Suparno M. , Dolan K.D. , Ng P.K.W.
Published: July 2006

ABSTRACT: A model was proposed to predict separate thermal and mechanical effects of extrusion cooking on thiamin retention. Thermal effects were determined by heating small samples of wheat flour mixed with 0.30% (wt/ wt) thiamin hydrochloride isothermally at 140 °C, 151 °C, and 161 °C for different times. The calculated activation energy and rate constants at each temperature were 67.28 kJ/g mol and 0.00869/min, 0.0145/min, and 0.0224/min, respectively. The “extruder constant” was estimated as 27.7/rev, based on a matching‐viscosity method. Wheat flour with 0.30% (wt/wt) thiamin was extruded at different screw speeds. Mechanical effects caused 89.7% to 94.4% of total thiamin loss. This research provides a generalized method to “fingerprint” the extrusion process.
Effects of Addition of Sucrose and Salt, and of Starvation upon Thermotolerance and Survival During Storage of Freeze‐dried Lactobacillus delbrueckii ssp bulgaricus
Authors: Carvalho A.S. , Silva J. , Ho P , Teixeira P. , Malcata F.X. , Gibbs P.
Published: July 2006

ABSTRACT: Increased survival of freeze‐dried cells of Lactobacillus bulgaricus was observed when the drying medium was supplemented with sucrose; however, the magnitude of such protection was dependent on the growth medium used. Supplementing the growth medium with NaCl markedly increased survival of dried cells, and only a small effect was exerted by the composition of the drying medium or prior to starvation of cells. The D57 values of Lactobacillus bulgaricus cells grown in MRS were about half of those of cells grown in MRS supplemented with sucrose, with sucrose plus NaCl, or with NaCl.
Overcoming the Taste Stigma of Soy
Authors: Wansink B.
Published: July 2006

ABSTRACT: Can labels unknowingly influence a person's taste perceptions? Using a “phantom ingredient” taste test, the presence or absence of a labeled ingredient (soy) was shown to influence sensory evaluations of a food. In particular, a nutrition bar wrongly purporting to contain soy generated negative ratings of taste, aftertaste, and attitude, yet generated favorable ratings of its nutritiousness. Because there was actually no soy in the product, these differences represent biases caused by ingredient labeling. Given the appropriate segment of consumers (health‐oriented), ingredient labeling may have more favorable consequences. This power of suggestion might also be expanded to other ingredients or processes, such as those involving biotechnology or organic production.
Chiral Evaluation of Aroma‐active Compounds in Real Complex Samples
Authors: Ruiz del Castillo M.L. , Caja M.M. , Blanch G.P. , Herraiz M.
Published: July 2006

ABSTRACT The enantiomeric distribution of aroma‐active compounds resulting from stereospecific biosyn‐thetic pathways was established using a multidimensional chromatographic system, which involves the on‐line coupling of reversed‐phase liquid chromatography and gas chromatography (RPLC‐GC). The proposed approach allowed the rapid determination of the enantiomeric composition of chiral terpenes such as α‐pinene, limonene, linalool and α‐terpineol in different products (that is, orange aroma, orange essential oils, and fruit beverage) without requiring the previous concentration of the sample. Relative standard deviation values lower than 7.5% were obtained for the investigated compounds. Applications to the authentication of fruit products based on both the R‐ and S‐form contents of chiral terpenes were considered.
Interaction and Functionality of Mixed Myofibrillar and Enzyme‐hydrolyzed Soy Proteins
Authors: Feng J. , Xiong Y. L.
Published: July 2006

ABSTRACT Native and briefly heated (85 °C for 3 min) soy protein isolates (SPI) were partially hydrolyzed (4% DH) by Alcalase® and Flavourzyme™ before incorporation into a pork myofibril isolate (MPI) system. The hydrolysis of soy protein enhanced its interaction with MPI, leading to a decreased thermal stability of both soy and muscle proteins. Alcalase SPI hydrolysates, when compared with nonhydrolyzed SPI, improved viscoelastic properties and hardness of MPI gels, while Flavourzyme SPI hydrolysates had an adverse effect. Hydrolyzed SPI augmented emulsifying properties of MPI; the specific efficacy depended upon the type of enzymes used, the SPI:MPI ratio, and whether SPI was heated before hydrolysis.
Pasting and Crystalline Property Differences of Commercial and Isolated Rice Starch with Added Amino Acids
Authors: Liang X. , King J.M.
Published: July 2006

ABSTRACT This study compared effects amino acid structure and type on the pasting properties and crystallinity of rice starch isolated from flour. Amino acids were added at 2 and 6% of the starch (dry basis) for RVA analyses. Charged amino acids had more of an influence on pasting properties than neutral amino acids. Our results indicated that the negatively charged amino acids had a similar effect as that of the positive charged amino acids for decreasing cooking stability of the starch, but opposite effects on retrogradation tendency. Charged amino acids increased the crystallinity of the starch, potentially enhancing resistant starch nature.
Biochemical Properties and Consumer Acceptance of Pacific Whiting Fish Sauce
Authors: Tungkawachara S. , Park J.W. , Choi Y.J.
Published: July 2006

ABSTRACT Biochemical characteristics of fish sauce made from Pacific whiting whole fish and a mixture (1:1) of its byproducts were investigated at 0, 1, 3, and 9 mo. As fermentation time extended, the degree of hydrolysis, total nitrogen content, amino nitrogen content, and hypoxanthine content increased, while inosine content, moisture content, and pH decreased. Degree of hydrolysis was significantly different at 9 mo of fermentation. All cathepsin activities were negligible after 3 mo. Consumer tests showed a nonsignificant difference in overall acceptance between our samples and commercial anchovy fish sauce (P > 0.05). This study demonstrated that surimi byproducts can be utilized as raw material for fish sauce.
Citric Acid and Sodium Citrate Effects on Reducing Pink Color Defect of Cooked Intact Turkey Breasts and Ground Turkey Rolls
Authors: Sammel L.M. , Claus J.R.
Published: July 2006

ABSTRACT The ability of citric acid (0.1%, 0.2%, 0.3%) and sodium citrate (1.0%) to reduce the pink color defect induced with sodium nitrite (1 ppm, 5 ppm, 10 ppm) and nicotinamide (0.5%, 1.0%) in cooked, intact turkey breasts and ground turkey rolls was examined. Citric acid at 0.2% and 0.3% and sodium citrate consistently reduced natural or induced pink color in ground turkey rolls but had no effect on pink color of intact turkey breasts. Citric acid reduced pH and cooking yields, whereas sodium citrate did not. Therefore, sodium citrate may represent a viable option for use by poultry processors in reducing the occurrence of undesirable pink color in cooked, uncured, ground turkey.
Effect of Hydroxypropyl Methylcellulose‐Lipid Edible Composite Coatings on Plum (cv. Autumn giant) Quality During Storage
Authors: Perez‐Gago M.B. , Rojas C. , Del Río M.A.
Published: July 2006

ABSTRACT ‘Autumn Giant’ plums were coated with edible hydroxypropyl methylcellulose‐lipid composite coatings. The coatings consisted of beeswax or shellac, at 2 lipid content levels (20% and 60% dry basis). Weight loss of coated plums decreased as lipid content increased. No differences on weight loss were observed between uncoated and 20% lipid‐coated plums, indicating that the natural waxes of plums are as effective as coatings having 20% lipid. Water‐dipped plums experienced the highest weight loss. Fruit texture was not affected by coating after short‐term storage at 20 °C. However, for prolonged storage at 20 °C, the coatings significantly reduced texture loss and internal breakdown compared to uncoated and water‐dipped plums.
Quality Deterioration of Freeze‐dried Foods as Explained by their Glass Transition Temperature and Internal Structure
Authors: Khalloufi S. , Ratti C.
Published: July 2006

ABSTRACT Several quality parameters, such as volumetric shrinkage, internal structure, color changes, and glass transition temperature (Tg) of dry solids, were investigated during freeze‐drying of strawberry, apple, and pear, at various combinations of freezing and freeze‐drying temperatures. Process conditions had different impacts on the quality parameters. Both mercury intrusion and electron microscopy methods revealed a smaller pore radius and a denser internal structure for pear as compared to the other fruits. The shrinkage phenomena observed in freeze‐dried products could be interpreted from the Tg and the internal structure of the materials. Therefore, the determination of Tg of dry products could be used as an indicator for the best choice of products to be freeze‐dried.
Flavor Migration Out of Food Matrices: III. Migration of Limonene and Pyrazine in Formulated Dough Undergoing Microwave Reheating
Authors: Fu Y.‐C. , Tong C.‐H. , Lund D. B.
Published: July 2006

ABSTRACT Cold‐trap, on‐line sampling was applied to investigate migration of flavor compounds in a solid food matrix subjected to microwave heating. The activation energy levels for migration of limonene, pyrazine, and water are 58.2, 51.5, and 46.4 kJ/mol, respectively. The results of microwave reheating of limonene‐formulated dough showed no significant limonene concentration profile in the sample and less than 1% overall change in total limonene concentration. Because the flavor concentration used for this migration study is greater than the amount that would be added to real products, it can be concluded that after microwave reheating of flavor‐formulated dough, limonene is very stable and significant losses do not occur.
Reduction of Protease Activity in Simulated Milk Ultrafiltrate by Continuous Flow High Intensity Pulsed Electric Field Treatments
Authors: Bendicho S. , Barbosa‐Cánovas G.V. , Martín O.
Published: July 2006

A protease from Bacillus subtilis suspended in simulated milk ultrafiltrate (SMUF) was subjected to high intensity pulsed electric field (HIPEF) treatments of up to 6787 kJ/l, applying field strengths ranging from 19.7 to 35.5kV/cm up to 896 μs to evaluate the feasibility of this treatment on inactivating the enzyme. In addition, the influence of the pulse repetition rate (67, 89, and 111 Hz) and pulse width (4 and 7 μs) on the effectiveness of HIPEF treatments was tested. Protease activity was considerably reduced; a maximum inactivation of 62.7% was achieved after an 896‐μS treatment at 35.5 kV/cm and 111 Hz. Protease activity decreased exponentially with increase of input energy density, treatment time, field strength, and pulse repetition rate when exposed to HIPEF processing.
Inactivation Kinetics of Food Poisoning Microorganisms by Carbon Dioxide and High Hydrostatic Pressure
Authors: Park S‐J. , Park H‐W. , Park J.
Published: July 2006

The inactivation kinetics of food poisoning microorganisms using a combined treatment of carbon dioxide (CO2) with high hydrostatic pressure (HHP) was investigated. Staphylococcus aureus, Fusarium oxysporum, and Fusarium sporotrichioides were totally inactivated by a combined treatment of carbonation and HHP at 500 MPa. Bacillus subtilis, a spore forming bacteria, were not completely inactivated after the combined treatment. The microorganisms treated by carbonation and HHP were exponentially reduced in a pressure range and the Dp ‐value, the Zp‐value, and the activation volume were determined. UV absorbing materials leaked from injured cells. Morphological changes of the cells were observed by scanning and transmission electron microscopy.
Effect of Water Activity on the Growth Kinetics of Staphylococcus aureus in Ground Bread Crumb
Authors: Feeherry F.E. , Doona C.J. , Taub I.A.
Published: July 2006

The kinetics of Staphylococcus aureus (strains A, B, D) growth in bread crumb were determined as a function of water activity (Aw) from 0.836 to 0.909 at pH 5.2 to 5.5 and at 35°c. Adding glycerol to the dough or equilibrating the bread over saturated salt solutions adjusted the Aw of the bread. Growth kinetics data, plotted as enumerated colony counts versus incubation time, were fitted using the logistic function to determine maximum growth rates. Similar maximum growth rates resulted, irrespective of the method used to adjust Aw. Extrapolation of growth rate‐Aw results predicts the Aw corresponding to a zero growth rate.
Efficacy of Cetylpyridinium Chlorine on Salmonella Typhimurium and Escherichia coli O157:H7 in Immersion Spray Treatment of Fresh‐Cut Lettuce
Authors: Yang H. , Cheng Y. , Swem B.L. , Li Y.
Published: July 2006

Fresh‐cut lettuce inoculated with Salmonella enterica serovar Typhimurium and Escherichia coli O157:H7 was treated using cetylpyridinium chlorine (CPC) solution in a laboratory‐scale immersion spray system. With 0.7 kg/cm2 spray pressure and 1.5‐min spray time (ST), both bacteria were significantly reduced (P < 0.05) in 0.1% to 0.3% CPC spray treatments, compared with water spray controls. At the same ST, increasing spray pressure from 0.7 to 2.1 kg/cm2 further reduced bacteria by 0.5 to 1.5 log colony‐forming units (CFU)/g. The 0.2% and 0.3% CPC treatments resulted in the greatest reduction of S. serovar Typhimurium and E. coli O157:H7, respectively. Similar bacterial reduction could be achieved using shorter ST with extended post‐spray exposure time. No color change on the lettuce was observed after CPC treatment.
Sodium Chloride (0.8 M) as a Better Protein Extractant for Fish Meat Quality Assessments
Authors: Munasinghe D.M.S. , Sakai T.
Published: July 2006

The extractability of proteins by NaCl, KCl, and LiCl as affected by different ionic strengths and pH was compared to determine the best protein extractant. The individual proteins in the extracts were identified by electro‐phoresis. The optimum ionic strength (IS) at pH 7.0 for the protein extractability (PE) of NaCl, KCl, and LiCl were 0.8, 0.9, and 1.0, respectively. The PE of NaCl and KCl declined as pH changed from 6.0 to 8.0, whereas an opposite effect was observed for the LiCl. The NaCl had the highest PE, followed by LiCl and KCl. The maximum number of proteins (15 bands) was found at the optimum IS of each salt. However, the resolution and clarity of the protein bands were better in the NaCl extracts.
Singlet Oxygen Oxidation for 2‐Pentylfuran and 2‐Pentenyfuran Formation in Soybean Oil
Authors: Min D. B. , Callison A. L. , Lee H. O.
Published: July 2006

ABSTRACT: 2‐Pentylfuran and isomers of 2‐pentenylfuran are known to be mainly responsible for the undesirable reversion flavor of soybean oil. Solid‐phase microextraction ‐ gas chromatography ‐ mass spectrometry was used to isolate, separate, and identify 2‐pentylfuran and isomers of 2‐pentenylfuran from soybean oil containing 5 ppm chlorophyll in a gas‐tight sample bottle during oxidation under light. Both 2‐pentylfuran and isomers of 2‐pentenylfuran increase as light exposure time and added chlorophyll increased. The compounds were neither formed in the oil containing 5 ppm chlorophyll under dark nor in the chlorophyll‐free soybean oil under light. The singlet oxygen oxidation mechanism for the formation of 2‐pentylfuran from linoleic acid and isomers of 2‐pentenylfuran from linolenic acid are proposed. Removal of chlorophyll will reduce reversion flavor formation.
Effect of Hydrostatic Pressure on Molecular Conformation of Tilapia (Orechromis niloticus) Myosin
Authors: Ko W.C. , Jao C.L. , Hsu K.C.
Published: July 2006

ABSTRACT: Change in tilapia myosin molecular conformation due to pressurization at 50 to 200 MPa for 0 to 60 min was investigated. After a 50‐MPa treatment, tilapia myosins slightly decreased their total sulfhydryl contents and exposed their hydrophobic residues. Experimental results indicated that 100‐ and 150‐MPa treatments caused an apparent unfolding of myosins and a 1‐fold increase of their surface hydrophobicity (So). Myosins mainly formed intermolecular disulfide bonds with pressures of 100 to 200 MPa. In addition, increasing pressures altered the myosin conformation and decreased its Ca‐ATPase activity. Myosin apparently unfolded and formed disulfide bonds and hydrophobic interactions with pressurizing at 150 MPa.
Aflatoxin Removal from Pistachio Nuts by Natural Natrolite
Authors: Fooladi M.H. , Farahnaky A.
Published: July 2006

ABSTRACT: Natrolite was used to explore a physical and safe method to decontaminate aflatoxin‐containing pistachio lots. Pistachio nuts with low, medium, and high levels of aflatoxin were subjected to a washing process with a slurry of 5% natrolite. Using thin‐layer chromatography and scanning, the aflatoxin contents of the samples were measured. Aflatoxins B1 and B2 were found in pistachio nuts. The majority of total aflatoxins was aflatoxin B1 Natrolite treatment resulted in a 38% to 100% reduction in aflatoxin B1, depending on the initial aflatoxin level. Although natrolite was demonstrated to be an effective candidate to reduce aflatoxin B1, its efficacy against aflatoxin B2 was limited.
Treatment of Grapefruit Juice for Bitterness Removal by Amberlite IR 120 and Amberlite IR 400 and Alginate Entrapped Naringinase Enzyme
Authors: Mishra P. , Kar R.
Published: July 2006

ABSTRACT: Treatment of grapefruit (Citrus aurantium) juice with Amberlite IR 400 resulted in 69.23% naringin removal after 5 min exposure with significant clarification and 89.41% tartness (acidity) reduction. Amberlite IR 120 removed only 9% naringin in 1 min with increased shelf life of the juice without any change in clarity, quality, and naringin content. Alginate entrapped naringinase treatment of the juice resulted in 83.84% naringin hydrolysis at 55°C and 220 rpm in 180 min with 1.98 enzyme units/mL of juice. The soluble enzyme hydrolyzed only 65.53% naringin under similar conditions. Kinetic constant values of the immobilized and soluble enzymes were found to be 9.75 mM and 20 mM, respectively.
Low‐Temperature Blanching of Sweetpotatoes to Improve Firmness Retention: Effect on Compositional and Textural Properties
Authors: Jr. Walter W.M. , Truong V‐D. , Simunovic N. , McFeeters R.F.
Published: July 2006

ABSTRACT: Low‐temperature blanching of sweetpotatoes (SP) prior to cooking has been shown to significantly increase firmness retention. This research investigated the effect of blanching on firmness, pectin methylesterase activity (PME), pectin methylation, and galacturonic acid and cell wall material concentrations in SP tissue subjected to blanching and cooking treatments. PME activity decreased 82% after 20 min of blanching in water at 62°C, while sample firmness continued to increase with blanching time (3.5 N for unblanched and 19.0 N for 90 min blanched, and cooked tissue), indicating that firming due to pectin demethylation explains part of the observed increased firmness retention caused by low‐temperature blanching, but unknown factors also play a role.,
Functionality of Palm Oil as a Stabilizer in Peanut Butter
Authors: Aryana K.J , Resurreccion A.V.A. , Chinnan M.S. , Beuchat L.R.
Published: July 2006

ABSTRACT: Studies have shown that palm oil is an effective stabilizer in peanut butter. The objective of our investigation was to better define the role of palm oil as a stabilizer. Peanut butters without and with palm oil added at concentrations of 1.5, 2.0, and 2.5% (w/w of peanuts), and Fix‐X™ (hydrogenated rapeseed and cottonseed oils as commercial control) were stored at 0, 21, 30, and 45 °C for 23 wk. Palm oil improved the oil holding capacity (OHC) of peanut butters, but had no effect on their adhesiveness and hardness characteristics. The unstabilized and palm oil‐stabilized peanut butters were not as good as the Fix‐X™ stabilized peanut butters with regard to their OHC, hardness, and adhesiveness characteristics.
Modeling Selected Properties of Extruded Waxy Maize Cross‐Linked Starches with Neural Networks
Authors: Ganjyal G.M. , Hanna M.A. , Jones D.D.
Published: July 2006

ABSTRACT: Extrusion process is described as a complex multiple input, multiple output system. Various cross‐linked waxy maize starches were extruded at initial moisture contents of 20, 24, and 28% (dry basis) and screw speeds of 110, 150, and 190 rpm. Multiple Input, Single Output neural network models were developed for predicting individual product properties, and Multiple Input, Multiple Output models were developed for predicting selected product properties at 1 time from selected input process parameters. Models varied only in the number of hidden neurons, ranging between 8 and 14. Models had R2 values of 0.89 and greater. Models explained the process and the influence of selected process parameters on selected product properties.
Surface Characterization of Caramel at the Micrometer Scale
Authors: Morton D.N. , Roberts C.J. , Hey M.J. , Mitchell J.R. , Hipkiss J. , Vercauteren J.
Published: July 2006

ABSTRACT: The surface of caramel has been imaged using pulsed force atomic force microscopy (AFM) and scanning thermal microscopy, revealing shallow depressions in the surface of 1 to 10μm in dia that have a higher adhesion to the silicon AFM probe and a lower stiffness and different thermal character than the surrounding sample. This is consistent with the view of caramel as fat droplets within a matrix of sugars. As confirmation, the depressed regions were identified by infrared microscopy as consisting mainly of fat in a matrix of sugar. AFM also reveals that regions surrounding the depressions are decorated with thin (about 6nm) plate‐like features that display a higher stiffness than the rest of the matrix. We propose that these are of crystalline origin and most probably consist of fat.
Effect of Cold Storage on the Stability of Chub and Horse Mackerel Myoglobins
Authors: Chen H.‐H.
Published: July 2006

ABSTRACT: The myoglobin (Mb) thermal stability of chub mackerel and horse mackerel during cold storage as well as their Mb removal efficiency (MRE) by air‐flotation washing (AFW) were investigated. The Mb of horse mackerel was less stable than that of chub mackerel since the Mb of horse mackerel was more sensitive to heat than that of chub mackerel within 40 to 60 °C. During refrigerated or frozen storage, the phase transition temperature shifted to lower temperature and denaturation rate of Mb and the metmyoglobin (metMb) content increased, indicating that the cold storage lowered the Mb thermal stability. Cold storage also lessened the MRE by AFW, and this effect was more noticeable in horse mackerel than in chub mackerel.
Microbiological Validation of Microwave‐Circulated Water Combination Heating Technology by Inoculated Pack Studies
Authors: Guan D. , Gray P. , Kang D.‐H. , Tang J. , Shafer B. , Ito K. , Younce F. , Yang T.C.S.
Published: July 2006

A 915‐MHz Microwave‐Circulated Water Combination (MCWC) heating technology was validated for a macaroni and cheese product using inoculated pack studies. Before the tests, heat resistances of a Clostridium sporogenes (PA 3679) spore crop were determined in neutral phosphate buffer and macaroni and cheese product. Trays of macaroni and cheese products were subjected to 3 processing levels: target process (F0= 2.4), under target process (F0= 1.2), and over target process (F0= 4.8). The inoculated packs were evaluated by count‐reduction method and end‐point method. The microbial results showed that microbial destruction resulting from MCWC heating technology matched the calculated degree of sterilization (F0 value). This study suggests that the MCWC heating technology has potential in sterilizing packaged foods.
D and z Values of Salmonella, Listeria innocua, and Listeria monocytogenes in Fully Cooked Poultry Products
Authors: Murphy R.Y. , Duncan L.K. , Beard B.L. , Driscoll K.H.
Published: July 2006

: The D and z values of Salmonella, Listeria innocua, and Listeria monocytogenes were obtained for different ready‐to‐eat poultry products, including chicken, turkey, and duck. The D values of Salmonella, L. innocua, and L. monocytogenes were 151.5 to 0.1 min at 55 to 70°C, and the z values of Salmonella, L. innocua, and L. monocytogenes were 4.9 to 7.0 °C. Significant differences were found for the heat resistance of Salmonella, L. innocua, and L. monocytogenes among turkey, duck, and chicken products, indicating that the kinetic values of a certain pathogen in a specific product should be used for determining process lethality in fully cooked and vacuum‐packaged poultry products during post‐cook heat treatments.
Inactivation of Escherichia coli O157:H7 on Inoculated Alfalfa Seeds with Pulsed Ultraviolet Light and Response Surface Modeling
Authors: Sharma R.R. , Demirci A.
Published: July 2006

: Escherichia coli O157:H7‐inoculated alfalfa seeds with seed layer thicknesses of 1.02 to 6.25 mm were subjected to pulsed UV light for up to 90 s at a 8‐cm distance from the UV strobe. Population reductions higher than 4 log10 colony‐forming units (CFU)/g were achieved. For effect of distance from the UV strobe, seeds with 6.25‐mm layer thickness were treated 3 to 13 cm from the strobe. Reductions at shorter distances, such as 60 s at 5 cm (1.93 log10 CFU/g) and 60 to 90 s at 8 cm (4.89 log10 CFU/g), were significantly higher (P≤ 0.05). Data from the treatments were used to develop empirical models as a function of distance or layer thickness and treatment time for predicting the population of E. coli O157:H7 during pulsed UV‐light treatment. This study demonstrates that pulsed UV light holds promise for eliminating pathogens from alfalfa seeds, and the models developed can be useful predictive tools.
Antioxidant and Antibacterial Activities of Punica granatum Peel Extracts
Authors: Negi P.S. , Jayaprakasha G.K.
Published: July 2006

ABSTRACT: Pomegranate peels were powdered and extracted with ethyl acetate, acetone, methanol (MeOH), and water for 1 h each at room temperature. Radical‐scavenging activity of dried ethyl acetate, acetone, MeOH, and water extracts of pomegranate peels were compared with butylated hydroxyanisole at 5, 10, 25, and 50 ppm by high‐performance liquid chromatography method using 1, 1‐diphenyl‐2‐picrylhydrazyl. MeOH extract exhibited stronger radical‐scavenging effect than others. MeOH extract showed marked reducing power in potassium ferricyanide reduction method. Antibacterial activity of acetone, MeOH, and water extracts was evaluated by pour plate method against a few Gram‐positive and Gram‐negative bacteria. Acetone extract showed the highest antibacterial activity, followed by MeOH and water extract.
Effect of Fat Level and Partial Replacement of Pork Backfat with Olive Oil on the Lipid Oxidation and Volatile Compounds of Greek Dry Fermented Sausages
Authors: Muguerza E. , Ansorena D. , Bloukas J.G. , Astiasarán I.
Published: July 2006

ABSTRACT: High‐ and reduced‐fat Greek fermented sausages were produced with 30% and 20% total fat in the initial formulation. The same products were manufactured with a partial replacement of pork backfat with 20% olive oil. The influence of the modification of the lipid fraction on the oxidation process was evaluated after 2 mo of storage. The reduction of fat increased thiobarbituric acid (TBA) values, total aldehydes, and typical lipid oxidation compounds (hexanal, 2‐hexenal, 2‐octenal). A significant decrease in oxidation was detected in batches containing olive oil, particularly in the sausages with the highest olive oil content. This addition decreased, in both fat level products, TBA values and hexanal, 2‐hexenal, 2,4‐hexadienal, benceneacetaldehyde, tt,2,4‐nonadienal, and pentadecanal. The addition of olive oil significantly increased monounsaturated fatty acids content.
Isolation of Peptides with Angiotensin I‐converting Enzyme Inhibitory Effect Derived from Hydrolysate of Upstream Chum Salmon Muscle
Authors: Ono S. , Hosokawa M. , Miyashita K. , Takahashi K.
Published: July 2006

In order to utilize upstream chum salmon as a component of nutraceutical food, their defatted muscle proteins were hydrolyzed with 5% thermolysin. The resulting hydrolysate showed high inhibitory activity against angiotensin I‐converting enzyme (inhibitory concentration50= 27.9 protein μg/mL) in vitro. A significant reduction of systolic blood pressure was observed when 500 and 2000 mg/kg of body weight were orally administered into spontaneously hypertensive rats. Angiotensin I‐converting enzyme inhibitory peptides contained in the hydrolysate were isolated with various chromatographs. These 6 active peptides were Trp residue‐containing dipeptides: Trp‐Ala, Val‐Trp, Trp‐Met, Met‐Trp, Ile‐Trp, and Leu‐Trp. The inhibitory concentration50 values of these dipeptides ranged from 2.5 μM to 277.3 μM.
Effect of Antioxidants on the Production of Off‐Odor Volatiles and Lipid Oxidation in Irradiated Turkey Breast Meat and Meat Homogenates
Authors: Lee E.J. , Ahn D.U.
Published: July 2006

The addition of gallate, sesamol, trolox, and tocopherol was effective, but sesamol, sesamol + tocopherol, and gallate + tocopherol were among the most effective antioxidants in reducing thiobarbituric acid reactive substances, volatile production, and off‐odor intensity in turkey breast homogenates. Also, these 3 antioxidant treatments were effective in controlling lipid oxidation and off‐odor intensity in both vacuum and aerobically packaged patties. However, aerobic packaging was better than antioxidant treatments in reducing off‐odor intensity of irradiated turkey patties. Antioxidants had no effect on redness, but increased lightness and yellowness of irradiated turkey breast. It was concluded that a combination of antioxidant and aerobic packaging was more useful than antioxidant and vacuum packaging in controlling off‐odor problems in irradiated raw turkey meat.
Characterization of Lipase‐Catalyzed Structured Lipids from Selected Vegetable Oils with Conjugated Linoleic Acid: Their Oxidative Stability with Rosemary Extracts
Authors: Lee J.‐H. , Kim M.R. , Kim H.‐R. , Kim I.‐H. , Lee K.‐T.
Published: July 2006

Response surface methodology was used to optimize the lipase‐catalyzed transesterification reaction between conjugated linoleic acid (CLA) and soybean oil. On the basis of the model, structured lipids (SLs) were synthesized from CLA and soybean oil or sunflower oil. CLA was incorporated in SL‐soybean (24.4 mol%) and SL‐sunflower (23.1 mol%), respectively. Isomerization to trans, trans CLA was observed during the reaction. Throughout the oxidation study, all SLs showed higher peroxide values (POVs), p‐anisidine values, and 2‐thiobarbituric acid‐reactive substance values than their counterparts. Rosemary extracts with a different amount (100 to 300 ppm) could effectively reduce oxidation in soybean oil, sunflower oil, and their SLs.
Effects of Ascorbic Acid and Antioxidants on the Lipid Oxidation and Volatiles of Irradiated Ground Beef
Authors: Nam K.C. , Min B.R. , Park K.S. , Lee S.C. , Ahn D.U.
Published: July 2006

Beef loins, aged for different lengths of time post slaughter, were treated with ionizing radiation. Irradiated ground beef produced volatile sulfur compounds (S‐volatiles) responsible for the unique irradiation odor and accelerated lipid oxidation. The quality changes by irradiation became greater as aging and storage time increased. During aerobic storage, the S‐volatiles disappeared whereas volatile aldehydes drastically increased in irradiated beef. Addition of ascorbic acid at 0.1% (wt/wt) or sesamol +α‐tocopherol at each 0.01% level to ground beef before irradiation effectively reduced lipid oxidation and S‐volatiles. As storage time increased, however, the antioxidant effect of sesamol + tocopherol in irradiated ground beef was superior to that of ascorbic acid.
Hydrolyzed Fish Muscle as a Modifier of Rice Flour Extrudate Characteristics
Authors: CHOUDHURY G.S. , GAUTAM A.
Published: July 2006

The effects of fish protein hydrolysis time and fish solids level on macroscopic properties of extrudates were investigated. Arrowtooth flounder muscle was autolyzed for varying times; hydrolyzed muscle was recovered, dried, blended with rice flour at varying levels, and extruded using a twin‐screw extruder. Hydrolysis beyond 5 min had little effect on extrudate properties. Addition of hydrolyzed fish solids strikingly decreased the apparent density and breaking strength but increased extrudate porosity and expansion ratios. In general, the effect was greater when the level of fish solids was higher. Opposite and expected trends were observed for blends with unhydrolyzed fish solids. Fish solids level played a dominant role in increasing true density.
Separating the Role of Particles and the Suspending Fluid for the Flow of Soy Milks
Authors: Bodenstab S. , Juillerat M. , Bauer W. , Sommer K.
Published: July 2006

The paper describes a model and a simple experimental method to determine suspension transport properties, separating the role of particles from the suspending fluid. Shear stresses are described as consisting of 2 components: 1st, a shear stress caused by the flow of the suspending fluid and 2nd, a shear stress caused by direct interaction between suspended particles. We show that the determination of these shear stresses of a complex (food) suspension is largely independent of the definition of its suspending fluid. The rheological behavior of soy milks at low and intermediate moisture contents was studied, and results are compared with those obtained previously. The method evidences that the high viscosity of soy milks is predominantly caused by direct particle interaction.