bluuebunny/crossref_metadata_2025 huggingface dataset:
Adaptation of Classical Processes to New Technical Developments and Quality Requirements
Authors: Barbosa‐Cánovas G.V. , Uliano P. J
Published: August 2010

ABSTRACT: Food safety, minimal food processing, energy savings, and nutritional and sensory quality are key drivers in today's food industry. While achieving these objectives, classical approaches to processing food are evolving to meet consumer expectations and regulatory requirements. Food equipment manufacturers are constantly trying to adapt classical technologies to their equipment, and it is amazing to see how old principles and techniques have evolved to meet new expectations in ways never imagined before. This article reviews the recent developments in classic unit operations in food processing, specifically, dehydration, freezing, and canning. Special attention is given to overall capacities, food quality, and economic aspects. Also included in this article are unit operations that have been technologically revisited to come up with truly creative ways to process foods in the future.
Effect of Storage Time on Raw Sardine (Sardina pilchardus) Flavor and Aroma Quality
Authors: Prost C. , Hallier A. , Cardinal M. , Serot T. , Courcoux P.
Published: August 2010

ABSTRACT: Qualitative and semi‐relative quantitative changes in flavor profiles associated with the storage of raw sardine (Sardina pilchardus) were investigated. A sensory panel generated a list of 20 odorant descriptors of raw sardine. Forty‐seven volatile components were identified by gas chromatography‐mass spectrometry and were quantified by gas chromatography‐flame ionization detector (GC‐FID). Among them, 34 were highlighted as potent odorants using an olfactometric method. (E,E)‐2,4‐octadienal, E‐2‐penten‐1‐ol and 2,3‐butanedione are the most potent odorants of raw sardine. The odor‐active compounds responsible for oxidized flavors increased during storage, whereas sulfur‐containing compounds associated with marine odors decreased. These results could be related to the increase in rancidity aroma and the decrease in marine/iodized aroma identified by the sensory panelists in stored raw fish.
Comparison of Texture of Yogurt Made from Conventionally Treated Milk and UHT Milk Fortified with Low‐heat Skim Milk Powder
Authors: Krasaekoopt W. , Bhandari B. , Deeth H.
Published: August 2010

ABSTRACT: The textures of yogurt made from ultra‐high temperature (UHT) treated and conventionally treated milks at high total solids were investigated. The yogurt premixes, fortified with low‐heat skim milk powder to 16%, 18%, and 20% total solids, were UHT processed at 143°C for 6 s and heated at 85°C for 30 min using the conventional method. The onset of gelation was delayed in the UHT‐processed milk compared with conventionally heated milk. During fermentation, the viscosity of yogurt made from UHT‐treated milk at 20% total solids was close to that of yogurt made from conventionally treated milk with 16% total solids. However, after storage for ≥ 1 d, the yogurt made from UHT‐treated milk had lower viscosity and gel strength than the yogurt made from conventionally treated milk. The solids level had no influence on yogurt culture growth.
Mathematical Frameworks for Modeling Listeria Cross‐contamination in Food‐
Authors: Schaffner D.W.
Published: August 2010

ABSTRACT: The possibility of modeling the cross‐contamination of Listeria species, total Listeria monocytogenes, or specific L. monocytogenes strains using a quantitative mathematical model using Monte Carlo simulation techniques is proposed. This article illustrates this approach using 2 different models: one that tracks L. monocytogenes number and prevalence for 4 different strains (Model I) and one that tracks only prevalence for a single strain (Model II). These models have been developed to provide a starting framework for predictive modelers and scientists studying L. monocytogenes to begin research together with the ultimate goal of understanding and controlling L. monocytogenes in food‐processing plants.
Sensory Factors Contributing to the Identification of the Animal Species of Meat
Authors: Matsuishi M. , Igeta M. , Takeda S. , Okitani A.
Published: August 2010

ABSTRACT: The aim of the present study was to clarify by means of sensory tests whether taste, aroma, or texture is the dominant contributor to people's ability to identify the animal species of meat. The meat samples used were loins of beef, pork, and lamb; chicken thigh; and aigamo (crossbreed of domestic duck and wild duck) breast. Panelists (32 to 35 persons) wearing eye masks ate cooked pieces, patties, and heated soups prepared from the meats of these 5 species with and without pinching their noses to regulate the aroma sensation, attempted to identify the species, and gave reasons for their identifications. In the test involving meat pieces and pinched noses, the percentage of panelists identifying chicken correctly was the highest, at 72%, whereas the percentages of correct identification for all other animal species were less than 50%; however, values were higher for each species in tests without nose pinching. In the tests of meat patties involving pinched noses, the percentage of correct identification for each animal species was slightly lower in comparison with the tests of meat pieces; however, the values were higher in tests without pinched noses. In the tests of soups using pinched noses, the percentage of correct identification for each animal species was lower than 30%; however, the values were higher in tests without pinched noses. These results led us to the conclusion that aroma is the most important contributor to the identification of the animal species of meat, and texture is the 2nd most important contributor. The contribution of taste appears much smaller than that of aroma and texture.
The Role of Biotechnology in Modern Food Production
Authors: LEE CHERL‐HO
Published: August 2010

ABSTRACT: Modern food production technology is given great challenges by the emerging fields of biotechnology and molecular biology. Knowledge of conventional fermentation technology is upgraded by the gene level explanations of enzyme actions and physiological functions of biomaterials derived therefrom. The use of genetically modified organisms (GMOs) and their products in food widens the availability of resources while also raising public interest about safety and labeling. As an example of the application of molecular biology in conventional fermentation technology the selection of proteases from a Bacillus species grown in Korean traditional soybean fermentation starter, Meju, and the production of peptides with blood cholesterol lowering effect, obtained from soybean protein hydrolysate, are presented. Recent developments in the Korean bioindustry are reviewed as an example of the role of biotechnology in the food industry. The present status of GMO enzymes in food production is reviewed and safety issues about GMO use in the food system are discussed.
Inactivation of in Apple Juice by Radio Frequency Electric Fields
Authors: EVEKE D. J. G , BRUNKHORST C.
Published: August 2010

ABSTRACT:Heat pasteurization may detrimentally affect the quality of fruit and vegetable juices; hence, nonthermal pasteurization methods are actively being developed. Radio frequency electric fields processing has recently been shown to inactivate yeast in water at near‐ambient temperatures. The objective of this study was to extend the radio frequency electric fields (RFEF) technique to inactivate bacteria in apple juice. A converged‐field treatment chamber was developed that enabled high‐intensity RFEF to be applied to apple juice using a 4‐kW power supply. Finite element analyses indicated that uniform fields were generated in the treatment chamber.Escherichia coliK12 in apple juice was exposed for 0.17 ms to electric field strengths of up to 26 kV/cm peak over a frequency range of 15 to 70 kHz. The population ofE. coliwas reduced by 1.8 log following exposure to an 18 kV/cm field at an outlet temperature of 50 °C. Raising the temperature increased inactivation. Intensifying the electric field up to 16 kV/cm increased inactivation; however, above this intensity, inactivation remained constant. Radio frequencies of 15 and 20 kHz inactivatedE. colibetter than frequencies of 30 to 70 kHz. Inactivation was independent of the initial microbial concentration between 4.3 and 6.2 log colony‐forming units (CFU)/mL. Applying 3 treatment stages at 50 °C increased inactivation to 3 log. The electric energy for the RFEF process was 300 J/mL. The results of the present study provide the 1st evidence that RFEF processing inactivates bacteria in fruit juice at moderately low temperatures.
An Improved Method for a Hydrophobic Grid‐membrane Filter System to Detect Heat‐injured Foodborne Pathogens in Ground Beef
Authors: WU V. C. H. , FUNG D. Y. C.
Published: August 2010

ABSTRACT: Recovery of heat‐injured pathogens (Escherichia coli O157:H7, Listeria monocytogenes, Salmonella Typhimurium, and Yersinia enterocolitica) in ground beef samples was studied by the thin agar layer (TAL) and TAL = Oxyrase® (TALO) methods in conjunction with the ISO‐GRID® hydrophobic grid‐membrane filter (HGMF). This new combination using ISO‐GRID HGMFs with the TAL and TALO methods improved the efficiency (P < 0.05) of recovery of pathogens. In addition, the TALO method showed a higher percentage increase of recovery than the TAL method because of stimulation of Oxyrase in growth of pathogens. The combination allows the detection of very low numbers of pathogens in food.
Effect of Grinding Temperature on Hydroperoxide and Off‐flavor Contents during Soymilk Manufacturing Process
Authors: MIZUTANI T. , HASHIMOTO H.
Published: August 2010

ABSTRACT:Hydroperoxides andn‐hexanal of soymilk made at different temperatures in the soybean grinding process were investigated. Both hydroperoxides andn‐hexanal showed maximum amounts at 30°C, 37.78 μmol/g, and 1.94 mg/g, respectively. However, at 3°C and 80°C, amounts of hydroperoxides were about half of that at 30°C.N‐hexanal showed high correlation with hydroperoxides except for at 80°C. It suggests that controlling the grinding temperature is effective to reduce hydroperoxidation and off‐flavor content. Protein solubility an important index of soymilk, was decreased as the temperature increased. Grinding soybeans at low temperature is considered an economical method to produce soymilk having less off‐flavor and high protein.
Influence of High‐Pressure Treatment at 25°C and 80°C on Folates in Orange Juice and Model Media
Authors: UTZ P. B , SERFERT Y. , GARCIA A. FERNANDEZ , DIETERICH S. , LINDAUER R. , BOGNAR A. , TAUSCHER B.
Published: August 2010

ABSTRACT: The influence of high‐pressure treatment on the 3 main folate species present in orange juice was assessed under conditions similar to those used in high‐pressure pasteurization and sterilization using freshly squeezed orange juice and different model orange juices. The latter were used also to determine the influence of matrix components, pH, and excess ascorbic acid. Excess ascorbate strongly protected folates against pressure and heat. Pressurization at 600 MPa and 80°C affected model juice folates synergistically, and pressure increased the formation of 5,10‐methenylfolate. In fresh orange juice, components other than ascorbate additionally stabilized folates, thus pressure preservation and pressure sterilization appeared very feasible.
Characterization of the Yeast Population Involved in the Production of a Typical Italian Bread
Authors: Vernocchi P. , Valmorri S. , Dalai I. , Torriani S. , Gianotti A. , Suzzi G. , Guerzoni M. E. , Mastrocola D. , Gardini F.
Published: August 2010

ABSTRACT: This work was aimed to characterize the yeast population of Ferrara bread, a baked product to which the European Community assigned the Protected Geographical Indication, and to focus the attention on the yeasts of the sourdough used for its production. In addition, the physicochemical parameters were monitored. High amounts of acetic acid were found in the sourdough (more than 3 g/kg) because of the prevalence of heterofermentative lactic acid bacteria. The major part of the yeasts were not able to ferment maltose. Candida milleri was the dominant species (as shown by random amplification of polymorphic DNA‐polymerase chain reaction analysis), but several biotypes of this species coexisted and colonized the sourdough.
Hamburger Composition and Microwave Heating Uniformity
Authors: Ryynänen S. , Risman P.O. , Ohlsson T.
Published: August 2010

ABSTRACT: The importance of recipe modifications on the microwave heating uniformity and dielectric properties of a hamburger was investigated in a household oven. Factorial design was used in the experimental setup, and data were evaluated by analysis of variance. Temperature was monitored by a fiberoptic device, infrared imaging, and thermocouples. Dielectric data of the hamburger components were measured by a cavity perturbation method. An analytical model for calculating microwave energy balance was developed and compared with experimental data, and numerical modeling was also used in the analysis, and the results were compared. Uneven heating is difficult to improve by recipe modifications only. The differences between the analytical and numerical modeling indicate that the uniformity of heating in relatively small loads is difficult to achieve.
Effect of Harvest Maturity on the Sensory Characteristics of Fresh‐cut Cantaloupe
Authors: Beaulieu J.C. , Ingram D.A. , Lea J.M. , Bett‐Garber K.L.
Published: August 2010

ABSTRACT:Maintaining flavor, aroma, microbial, and postharvest quality after processing and throughout the distribution chain is a major challenge facing the fresh‐cut fruit industry. Flavor and aroma are most often the true indicators of shelf‐life from the consumer's point of view. Changes in post‐cutting sensory attributes during freshcut storage at 4 °C in cantaloupe harvested at 4 distinct maturities (¼, frac12;, frac34;, and full slip) were subsequently investigated. Trained descriptive sensory panelists were used in a 2‐y study to assess sensory differences after 0, 2, 5, 7, 9, 12, and 14 d. A texture analyzer was also used in an attempt to verify textural properties revealed by the panelists. The V4‐slip harvested fruit were firmer than the other 3 maturities, and ¼‐slip cubes retained the most firmness through freshcut storage. Correspondingly, fruity and sweet aromatic flavor were significantly less intense in the ¼‐slip cubes compared with ½‐ and ¾‐slip maturities. Sweet taste was consistently significantly less intense in the ¼‐slip cubes than the other maturities during the entire storage period. Hardness was more intense (harder) in ¼‐slip cubes during 0 to 9 d. This trend was almost identical in the instrumental texture determinations for the force and slope at the 1st bioyield point of the force deformation curves. Meanwhile, ¼‐slip cubes were significantly less intense than the other maturities in surface wetness and moisture release on day 0 and throughout storage. It appears that fresh‐cut cantaloupe cubes with desirable sensorial attributes can be prepared with fruit when harvested ½ slip but not from ¼‐slip fruit.
Developing a Lexicon for Descriptive Analysis of Soymilks
Authors: N'Kouka K. Day , Klein B.P. , Lee S.‐Y.
Published: August 2010

ABSTRACT:A descriptive vocabulary was developed to fully describe the sensory characteristics of soymilks. Five commercial soymilks and 1 laboratory‐prepared soymilk were used in the study. Nine subjects participated in 8 round‐table discussions to develop descriptive language and references. The 6 soymilks were evaluated in 4 replications using this language. Principal component analysis was conducted on the resulting data to eliminate redundant terms and differentiate between samples. Thirty‐one terms were identified to describe soymilks. The lexicon could be used as a starting place to describe any product containing soy; therefore, it will be beneficial to soy food processors in research and development and quality assurance.
Influence of Commercial Diets on Quality Aspects of Cultured Gulf of Mexico Surgeon (Ancipenser oxyrinchus desotoi)
Authors: Oliveria A.C.M. , O'Keefe S.F. , Balaban M. , Sims C.A. , Portier K.M.
Published: August 2010

ABSTRACT: Cultured sturgeons were fed commercially available diets formulated for hybrid bass, catfish, and trout. The impact of these diets in the quality of the edible muscle was investigated through determination of processing yields, proximate compositions, fatty acid profiles, muscle color, and sensory characteristics. Sturgeon fed the catfish diet were significantly smaller but dressed fillets (percent live weight) were similar for all feeds. Consumer visual acceptability scores were highest for fillets from fish fed the catfish diet, and color differences were determined. Sturgeon fillets from fish fed the trout diet presented a yellowish orange coloration instead of a pale pink coloration. Results show that the diets tested had no detrimental impact in the composition of sturgeon fillets.
Prediction of the Sensory Quality of Canned Beer as Determined by Oxygen Concentration, Physical Chemistry Contents, and Storage Conditions
Authors: Corzo O. , Bracho N.
Published: August 2010

ABSTRACT:The objective of this research was to predict any sensory characteristics of canned beer related to its oxygen concentration, composition, temperature, and time intervals of storage. The initial content of oxygen and content of carbon dioxide, pH, color, turbidity, thiobarbituric acid, and bitterness were instrumentally evaluated during 16 wk and 3 storage temperatures. Simultaneously, 8 trained panelists evaluated the degree of oxidation, quality of bitterness, and sensory stability. Principal components regression adjusted models explained the 85% to 86% (P< 0.01) variability of the sensory characteristics. The results suggest that sensory characteristics of canned beer can be predicted by instrumental measures of its composition and storage conditions.
Influence of Maturity at Processing on Quality Attributes of Fresh‐cut Conference Pears
Authors: Solvia‐Fortuny R.C. , Alòs‐Saiz N. , Espachs‐Barroso A. , Martin‐Belloso O.
Published: August 2010

ABSTRACT: Influence of ripeness state of Conference pears on the respiration and quality changes of the minimally processed fruit was studied. The fruits processed at partially ripe maturity were the most suitable to obtain fresh‐cut products. Slightly under‐ripe pears exhibited less browning and firmness degradation. Treatments consisting of dips in 10 g/L ascorbic acid and 5 g/L calcium chloride and packaging in 15 cm‐2× m‐2× 24 day‐1× bar‐1 preserved the initial appearance of pear cubes for at least 14 d. Because of a significant inhibition of ethylene production, 0 kPa O2 initial atmosphere was effective in preventing quality changes. Presence of ethanol, as a result of fermentative anaerobic processes, increased with ripeness, especially beyond the 1st 21 d of storage at 4 °C. On the contrary, acetaldehyde was less affected than ethanol by processing and storage conditions.
Dynamic Rheological and Thermal Properties of Soft Wheat Flour Dough Containing Structured Lipid
Authors: Agyare K.K. , Xiong Y.L. , Addo K. , Akoh C.C.
Published: August 2010

ABSTRACT: The effect of substituting canola oil/caprylic acid structured lipid for shortening (at 0%, 25%, 50%, 75%, and 100% levels) on the viscoelastic and thermal properties of soft wheat flour dough (28.4% total lipid, 43% moisture) was determined using dynamic rheological and differential scanning calorimetry tests. Ambient frequency scans produced higher G″ (loss modulus) and G′ (storage modulus) values at increasing frequencies. Temperature scans revealed rapid G″ and G′ increases for dough heated to above 56 °C, apparently because of starch gelatinization. Three differential scanning calorimetry endothermic peaks were observed at 54 °C, 69 °C, and 93 °C, which were attributed to shortening transition and gelatinization of starch granules.
A New Method for Characterizing Fiber Formation in Meat Analogs during High‐moisture Extrusion
Authors: Yao G. , Liu K.S. , Hsieh F.
Published: August 2010

ABSTRACT: A noninvasive method based on fluorescence polarization spectroscopy was developed to measure the fiber formation of extruded meat analogs. Soy protein, wheat gluten, and unmodified wheat starch were mixed and extruded at high moisture conditions to form meat analogs with 60% to 72% moisture (w.b.). This newly developed method and a texture analyzer were used to analyze the fiber formation of extruded products as well as samples collected from different zones in the extruder and cooling die upon a dead‐stop operation. The results indicated that the texture profile analysis could not adequately describe the fiber formation while the new method showed good agreements with results obtained from visual inspection and digital imaging of the dissected samples.
Process Characteristics of Hydrolysis of Chitosan in a Continuous Enzymatic Membrane Reactor
Authors: Kuo C.H. , Chen C.C. , Chiang B. H.
Published: August 2010

ABSTRACT: Crude enzyme from Bacillus cereus NTU‐FC‐4 was used to hydrolyze chitosan of 66% deacetylation in a membrane reactor, operated at 45 °C and pH 5, to continuously produce chitooligosaccharides. Major oligomers in the product from the reactor were chitobiose, chitotriose, chitotetraose, chitopentaose, and chitohexaose. When the membrane reactor was operated at an enzyme/substrate ratio of 0.2 (unit/mg) and residence time of 100 min, it reached steady state in 2.5 h. The system could be operated for 15 h and still maintained a stable product composition. When the volume replacement exceeded 2.5, the productivity of the membrane reactor became higher than that of the batch reactor, and the difference between them became even greater when the volume replacement was further increased. The apparent Michaelis constant (Km) for the enzyme in the membrane reactor was 18.8 mg/mL, but the apparent Km was 5.4 mg/mL for the batch reactor, suggesting that the affinity of the enzyme for chitosan was lower in the membrane reactor compared with the enzyme in the batch reactor. The estimated values of apparent Vmax were 0.18 and 0.20 mg reducing sugar/mL/min for the enzyme in the membrane reactor and in the batch reactor, respectively, indicating that the enzyme activity was not greatly altered when used in the membrane reactor.
Effects of Protein Size Distribution and Dough Rheology on Hearth Bread Characteristics Baked at Different Processes and Scales
Authors: Færgestad E.M. , Tronsmo K.M. , Aamodt A. , Bjerke R , Magnus E.M. , Dingstad G. , Baardseth P.
Published: August 2010

ABSTRACT: The present study investigates the effect of flour and dough characteristics on the baking performance of hearth loaves, which are proved and baked without a tin. A number of experiments were performed at different scales. The most significant and consistent observation was a positive relationship between the protein quality and the form ratio of the loaves (height/width), in which the protein quality was evaluated by both large and small strain rheology, as well as by size distribution of the gluten proteins and other protein quality parameters. The volume of hearth loaves and the slice area are complex characteristics because they are combined functions of loaf height and loaf width; the loaf height was positively related to protein quality, whereas loaf width was negatively related. The total effect of this is not obvious. In general, the loaf volume is more strongly related to the loaf width than is the slice area. For the present material, differences in protein quality were not manifested as significant differences in loaf volume, whereas the slice area was positively correlated to the protein quality. The results obtained at different scales of the baking experiment agreed well with each other.
Extraction of Anthocyanins and Polyphenolics from Blueberry Processing Waste
Authors: Lee J. , Wrolstad R.E.
Published: August 2010

ABSTRACT: The effectiveness of temperature, SO2, citric acid, and industrial juice‐processing enzymes (n= 9) for producing extracts of blueberries (Vaccinium corymbosum, cv. Rubel) and blueberry skins that are rich in anthocyanins and polyphenolics were evaluated individually and/or in combination. Enzyme treatment had little effect on total monomeric anthocyanins and on total phenolics recovery. Various combinations of heat, SO2, and citric acid yielded extracts with higher concentrations of ACY and TP than the control. The distribution of anthocyanins and polyphenolics in ‘Rubel’ was also investigated. Anthocyanins existed almost exclusively in the skins, and polyphenolics were mostly in the skins with lesser amounts in flesh and seeds. Skins were also highest in antioxidant activity. All portions contained the same individual anthocyanins but in varying amounts. Cinnamic acid derivatives and flavonol‐glycosides were found in the skins and seeds, whereas the flesh contained only cinnamic acids.
Agroterrorism: Issues of Reality
Authors: ZINK DON L.
Published: August 2010

ABSTRACT: In the past, deliberate contamination of foods in the U.S. has been committed by individual criminals, disgruntled employees, or political activists with a narrow agenda. After September 11, 2001, every nation has had to consider a much wider range of food security issues. Food is a global commodity and nearly every country both exports and imports foods. Every nation must consider the security of its domestic production and look beyond its borders to its trading partners to assure the safety of its food supply. In the nearly 2 years since September 11, 2001, many steps have been taken to improve food security. New legislation has been enacted to strengthen the ability of government to respond to terrorist threats. New relationships have been forged between food security agencies, law enforcement, and the intelligence community. Virtually every segment of the domestic and imported food supply has come under scrutiny in an effort to identify points of weakness and appropriate protective measures. Gaps in our knowledge about specific agents and food processes have been identified and research to fill these gaps has been initiated. This effort will continue for the foreseeable future and could have a wide range of benefits, including improvements to food safety, a reduction in product counterfeiting, and a reduction in the “gray market” food trade. The scale and diversity of the U.S. food supply makes it an attractive target, but at the same time makes it very resilient and responsive to emerging threats.
Ability of Cyclodextrins to Entrap Volatile Beany Flavor Compounds in Soymilk
Authors: SURATMAN L. L. I. , JEON I. J. , SCHMIDT K. A.
Published: August 2010

ABSTRACT: The efficacy of cyclodextrins for entrapping volatile beany flavor compounds in soymilk was studied using gas chromatography‐headspace solid‐phase microextraction and descriptive sensory analysis. Cyclodextrin addition reduced headspace concentrations of most beany flavor compounds, with α‐cyclodextrin being more effective than γ‐cyclodextrin. During 1 wk of 7 °C storage, soymilks with cyclodextrins maintained reduced headspace concentrations of volatile compounds associated with beany flavors. However, no significant difference was found by the sensory panel between soymilks with and without added cyclodextrins either 1 or 7 d after manufacture. This discrepancy could be because of the high concentrations of hexanal and other beany flavor compounds that might have had an overpowering effect on the panelists.
Internal Premature Browning in Cooked Steaks from Enhanced Beef Round Muscles Packaged in High‐oxygen and Ultra‐low Oxygen Modified Atmospheres
Authors: SEYFERT M. , HUNT M. C. , MANCINI R. A. , KROPF D. H. , STRODA S. L.
Published: August 2010

ABSTRACT: Beef round muscles were injection‐enhanced to 6%, packaged in high‐oxygen (HiOx) or ultra‐low oxygen (LoOx) modified atmospheres, stored 7 d and displayed 2 d (HiOx) or stored 16 d and displayed 1 d (LoOx) at 0 °C, and cooked to 71.1 °C. Raw internal color for steaks in HiOx was lighter, redder, more yellow and saturated, and had more oxymyoglobin and less deoxymyoglobin than steaks in LoOx (P < 0.0001). Cooked internal color of steaks from HiOx appeared prematurely brown and was darker, less red, yellow, and saturated, and had more denatured myoglobin than steaks from LoOx (P < 0.0001). This study presents conclusive evidence that modified‐atmosphere packaging influences internal cooked color development of beef steaks.
Relationships among Headspace Oxygen, Peroxide Value, and Conjugated Diene Content of Soybean Oil Oxidation
Authors: CHUNG H. J. , COLAKOGLU A. S. , MIN D. B.
Published: August 2010

ABSTRACT: Relationships among headspace oxygen uptake, peroxide value, and conjugated dienes content in the oxidation of soybean oils in a gas‐tight bottle were studied for 24 h under light and 96 h in the dark at 55°C. The theoretical peroxide value determined by oxygen uptake continuously increased as storage time increased. The headspace oxygen method is simple and reproducible and may be the best analytical method to evaluate the oxidative stability of oils.
Improvement of Fish‐sauce Odor by Treatment with Bacteria Isolated from the Fish‐sauce Mush (Moromi) Made from Frigate Mackerel
Authors: Fukami K. , Funatsu Y. , Kawasaki K. , Watabe S.
Published: August 2010

ABSTRACT: A bacterium, which was isolated from fish‐sauce mush (moromi) of frigate mackerel and identified as Staphylococcus xylosus, could change notes of an odor in fish sauce made in Thailand. Volatile compounds of the fish sauce after incubation at 32 °C for 24 d with the cultured bacterium were analyzed by gas chromatogra‐phy. Although the contents of 2‐ethylpyridine and dimethyl trisulfide were reduced during the incubation, 4 volatile compounds, including 2‐methylpronal, 2‐methylbutanal, 2‐pentanone, and 3‐(methylthio)propanal, showed no significant quantity changes. On the other hand, although 3‐methyl‐1‐butanol and 2,6‐dimethylpyrazine were markedly increased, 3‐methylbutanoic acid was slightly increased. As a result of sensory evaluation, fishy, sweaty, fecal, and rancid notes of the fish sauce treated with the bacterium were all weaker than those of the nontreated fish sauce. No changes were found with respect to burnt, cheesy, meaty, and ammoniacal notes between fish sauce treated with the bacterium and that without treatment. Taken together, the odor of fish sauce was much improved by treatment with the isolated bacterium.
Comparison of Gel‐forming Properties of Silver Carp (Hypophthalmichthys molitrix) Surimi Prepared in Different Seasons
Authors: Yuan C. , Fukuda Y. , Kaneniwa M. , Chen S. , Cheng Y. , Wang X. , Konno K.
Published: August 2010

ABSTRACT: The gel‐forming properties of silver carp surimi made in different seasons were compared. Surimi prepared in winter and spring formed gel at 30°C, while autumn and summer surimi required a higher temperature of 40°C for gel formation. All surimi showed marked disintegration when incubated at 60°C. Ca2+‐ATPase inactivation rate of myofibrils prepared from 4 surimi samples showed that myofibrils in autumn and summer surimi were much more stable than those in winter and spring surimi by about 10°C. These results demonstrated a close relationship between the gel‐forming temperature of surimi and the thermal stability of myofibrils in surimi, namely that autumn and summer surimi containing stable myofibrils required higher temperature than winter and spring surimi for the gel formation.
Ripening Associated Phytochemical Changes in Mangos (Mangifera indica) Following Thermal Quarantine and Low‐Temperature Storage
Authors: Talcott Stephen T. , Moore Jennifer P. , Lounds‐Singleton Angela J. , Percival Susan S.
Published: August 2010

ABSTRACT: Fresh mangos entering the United States must be subjected to a thermal quarantine treatment to eliminate invasive pests, commonly followed by cold storage to extend shelf‐life. Changes in phytochemicals and their resultant antioxidant capacity after such treatments are unknown. These studies evaluated mature, green mangos subjected to a simulated quarantine treatment using hot water immersion at 50°C for 60 min and subsequent storage at 5°C and 20°C against their respective controls. Fruit held at 5°C were transferred to 20°C after 8 d of storage to complete ripening, whereby symptoms of chill injury were observed. Phytochemical, antioxidant capacity, and quality parameters were then assessed every 4 d as the fruit ripened over the next 20 d. Storage temperature during ripening and not the hot water treatment was the major factor contributing to changes in polyphenolic content, with antioxidant capacity unaffected by either postharvest treatments or ripening. Major polyphenolics identified were free gallic acid and 4 gallotannins that collectively increased in concentration by 34% as the fruit ripened, also independent of postharvest and storage treatments. Carotenoid concentrations were highest in hot water‐treated fruit stored at 20°C, whereas storage at 5°C initially delayed ripening. Despite appreciable differences in fruit quality during quarantine treatment or low temperature storage, only minor differences in antioxidant phytochemicals were observed.
Heat Transfer and Microbial Kinetics Modeling to Determine the Location of Microorganisms within Cucumber Fruit
Authors: Mattos F.R. , Fasina O.O. , Reina L.D. , Fleming H.P. , Breidt F. , Damasceno G.S. , Passos F.V.
Published: August 2010

ABSTRACT: Microbiological and modeling (combined heat transfer and microbial kinetic equations [HTMK] model) approaches were used to determine the location of microorganisms within cucumber. The total number of aerobes found within/on cucumbers varied from 105 to 107 colony‐forming units (CFU) /g. The highest and the least amount of microbiota were respectively found at the blossom end and middle part of the cucumbers and were within the 1st 6 mm of the cucumber surface. A comparison of the calculated thermal death time from the HTMK model with the values obtained from experimental data showed that total aerobic microorganisms were located within 0.65 mm of the fruit surface.
Effect of Irradiation on Microbial Safety and Nutritional Quality of Minimally Processed Bitter Gourd (Momordica charantia)
Authors: Khattak Misal Khan , Bibi Nizakat , Khattak Amal Badshah , Chaudry Muhammad Ashraf
Published: August 2010

ABSTRACT: The feasibility of gamma radiation in combination with low temperature was studied to ensure microbiological safety and maintaining physicochemical and sensory characteristics of minimally processed bitter gourd. Radio sensitivity (D10 values, that is, irradiation dose required for 90% reduction of microorganisms) for Salmonella paratyphae A and Escherichia coli were 0.28 kGy and 0.23 kGy, respectively. On the basis of D10 values, 5D10 values were determined and samples of minimally processed bitter gourd were irradiated up to 5D10 values, stored for 14 d at 5 ± 1 °C, and analyzed for total bacterial, fungal, and coliform counts. Ascorbic acid, acidity, texture, and sensory qualities were also studied. Results showed that an irradiation dose of 2.0 kGy significantly reduced the microbial count to keep the samples microbiologically safe for 7d. Sensory evaluation revealed that the samples received maximum scores for appearance and flavor (7.8 and 7.9, respectively) with radiation dose of 2.0 kGy and minimum score for control (6.5). Firmness and ascorbic acid content decreased significantly with increase in storage time and irradiation dose. All the samples were discarded during the 2nd wk of storage due to high bio‐burden.
Water Vapor Permeability and Mechanical Properties of Soy Protein Isolate Edible Films Composed of Different Plasticizer Combinations
Authors: Wan Vicki Cheuk‐Hang , Kim Moon Sook , Lee Soo‐Yeun
Published: August 2010

Water barrier and mechanical properties were measured for soy protein isolate (SPI) films plasticized with glycerol (GLY) and 1 of the plasticizers (propylene glycol [PG], polyethylene glycol [PEG], sorbitol [SOR], or sucrose [SUC]) at a ratio of 25:75, 50:50, 75:25, and 0:100. Plasticizer type as well as the plasticizer ratio in the GLY: plasticizer mixtures affected the film water barrier and mechanical properties. An addition of as little as 25% of a less hygroscopic plasticizer in the mixture induced significant reduction in water vapor permeability (WVP) of SPI films. However, at least 50% of the mixture needs to be GLY to show significant improvement in tensile strength (TS). From our experimental design, 50:50 GLY:SOR was the recommended combination because of its comparatively low WVP value and relatively high flexibility and strength. Incompatibility of GLY:PEG plasticizer mixture in SPI film was observed by surface migration of PEG from the film matrix.
Thermoultrasonication Eliminates Salmonellae from Intact Eggshells without Changing the Functional Properties of their Components
Authors: Cabeza Maria C. , García Maria L. , Hoz Lorenzo dela , Cambero Isabel , Ordontez Juan A.
Published: August 2010

We have previously reported that the simultaneous application of heat and ultrasound (thermoultrasonication) to intact eggs allows a reduction in the number of Salmonella enterica serovar Enteritidis present on the shell to a safe hygienic level in less severe conditions (temperature and time) than those usually recommended for common pasteurization. In the present work, the effect of thermoultrasonication on selected functional properties of egg compounds (shelf‐life, emulsifying and foaming capacities, emulsion and foam stabilities, texture properties of egg white gel, breakage resistance of shell, and sensory properties of cooked egg) has been studied under the conditions previously defined (54 °C for 5 min) for the developed treatment. No significant differences were obtained in any of properties assayed between thermoultrasonicated and untreated (fresh) eggs. We concluded that it is possible to pasteurize the surface of intact eggs by applying a thermoultrasonic treatment yielding a product with a safe level of S. Enteritidis and cause negligible damage to the thermolabile egg components.
Comparison of Milk Mineral, Sodium Tripolyphosphate, and Vitamin E as Antioxidants in Ground Beef in 80% Oxygen Modified Atmosphere Packaging
Authors: Vissa Avanthi , Cornforth Daren
Published: August 2010

The antioxidant effects of milk mineral (MM), sodium tripolyphosphate (STP), and vitamin E (E) were tested in raw ground beef packaged in 80% O2 modified atmosphere packaging, and held 1, 4, 7, or 14 d at 2 °C. Two levels of each antioxidant (0.75% and 1.5% MM, 0.25% and 0.5% STP, 50 or 100 ppm E) were compared with control samples without added antioxidants. Vitamin E was mixed with mineral oil or ethanol before mixing with meat samples. Thiobarbituric acid (TBA) values were highest (P < 0.05) in controls without antioxidants, and samples with added vitamin E. Lowest TBA values (<0.5) were in samples treated with 0.75% or 1.5% milk mineral. All ground beef samples maintained redness (a* > 10) through 4 d of storage. By day 7, ground beef treatments with added E were brown. After 14 d, ground beef with 0.75% MM was more red (P < 0.05) than other treatments or controls. Thus, 0.75% MM has possible application to prolong red color stability and inhibit lipid oxidation in ground beef packaged in high oxygen atmospheres.
Characterization of a Cabbage Off‐flavor in Whey Protein Isolate
Authors: Wright Joy M. , Carunchia Whetstine Mary E. , Miracle R. Evan , Drake Maryanne
Published: August 2010

Whey protein isolate (WPI) is a value‐added protein with multiple ingredient applications. A bland flavor is expected in WPI, and off‐flavors can limit its use in foods. Recently, a cabbage off‐flavor was noted in some WPI. The objective of this study was to characterize the source of cabbage flavor in WPI. WPI with and without cabbage flavor were collected, and descriptive sensory analysis was conducted on the rehydrated WPI using a trained panel and a previously identified sensory language. Volatile compounds were extracted by solvent extraction followed by solvent‐assisted flavor evaporation (SAFE), followed by gas chromatography‐mass spectrometry (GC‐MS) and gas chromatography‐olfactometry (GCO), to identify and characterize aroma‐active compounds. Dimethyl trisulfide (DMTS) (cabbage aroma) was identified by GCO and GC‐MS in WPI with the cabbage flavor. DMTS was quantified by solid‐phase microextraction (SPME) with GC‐MS. Orthonasal thresholds of DMTS in deodorized water and WPI were determined by ascending forced choice analysis, and descriptive analysis of model systems was used to confirm instrumental results. DMTS levels were 1.94 ± 0.26 and 3.25 ± 0.61 parts per billion (ppb) in WPI with cabbage flavor, and 0.44 ± 0.25 and 0.43 ± 0.18 ppb in those without cabbage flavor. The orthonasal thresholds for DMTS in water and WPI were 0.07 ± 1.28 parts per trillion (ppt) and 0.80 ± 0.45 ppb, respectively. Descriptive analysis of model systems confirmed the role of DMTS in the cabbage off‐flavor. Knowledge of the source of this flavor will aid in identification of ways to minimize or prevent DMTS formation in WPI.
The Stability of Poly(lactic acid) Packaging Films as Influenced by Humidity and Temperature
Authors: Holm Vibeke K. , Ndoni Sokol , Risbo Jens
Published: August 2010

The effect of moisture sorption on stability of poly(lactic acid) (PLA) films at food‐packaging conditions, obtained by different humidities (11% to 98% RH) and temperatures (5 °C and 25 °C), was investigated by decrease in number average molecular weight (Mn) and loss of tensile strength. Hydrolysis of the PLA ester linkages resulted in a 75% decrease over 130 d at 25 °C and 98% RH. At cooling conditions the decrease amounted to 35%. An equilibrium moisture sorption isotherm could not be determined as the irreversible hydrolysis of PLA induced an ongoing moisture uptake. The rate increased when the humidity and temperature increased from 5 °C to 25 °C. After 189 d at 98% RH, moisture sorption was 7 g/100 g and 86 g/100 g at 5 °C and 25 °C, respectively. Loss of tensile strength was minor and primarily due to reversible plastization by moisture. Only at 98% RH and 25 °C, loss of tensile strength became pronounced (45%). Consequently, the present PLA material is in general expected to be mechanically stable when packaging foods covering the region from dry to moist food and storage conditions from chill to ambient temperatures.
Effects of Electron Beam Irradiation on Physical, Textural, and Microstructural Properties of “Tommy Atkins” Mangoes (Mangifera indica L.)
Authors: Moreno Maria , Castell‐Perez M. Elena , Gomes Carmen , Da Silva Paulo F. , Moreira Rosana G.
Published: August 2010

This research focused on determining the dose levels suitable for electron beam irradiation of mangoes without detriment to the fruit's quality characteristics. Physicochemical, textural, respiration rates, microstructural, and sensory characteristics of “Tommy Atkins” mangoes irradiated at 1.0, 1.5, and 3.1 kGy using a 10 MeV (10 kW) linear accelerator with double‐beam fixture were determined. Fruits were stored at 12 °C and 62.7% RH for 21 d and evaluated at days 0, 5, 10, and 21. Nonirradiated mangoes served as controls. Irradiation did affect the textural characteristics of mangoes at doses higher than 1.0 kGy. Mangoes exposed to 1.5 and 3.1 kGy were softer and less stiff throughout storage. The radiation‐induced softening of the fruits may be associated with changes in the structural cell such as cracks and depressions on the surface and the breakdown of the cells and its components. Irradiation at 3.1 kGy affected the color of mangoes by the end of storage. Doses up to 1.5 kGy kept respiration rates at a normal level. Irradiation did not affect the specific gravity of mangoes, a parameter associated with fruit maturity levels. No effect of irradiation on pH, water activity, moisture content, acidity, and juiciness of mangoes was detected at the dose levels used in this study. Only fruits irradiated at 3.1 kGy were unacceptable to the sensory panelists in terms of overall quality, texture, and aroma. Electron beam irradiation of “Tommy Atkins” mangoes at 1.0 kGy is the recommended treatment to maintain the overall fruit quality attributes.
Postharvest Quality and Microbial Population of Head Lettuce as Affected by Moisture at Harvest
Authors: Fonseca Jorge M.
Published: August 2010

Iceberg lettuce was evaluated for yield, microbial population, and postharvest quality either following different irrigation termination (IT) schedules or before and after a rainfall event. Lettuce receiving late (4 d before harvest) IT showed increased weight and diameter, higher aerobic bacteria counts, and lower quality than plants subjected to early (16 d before harvest) IT. Middle (8 d before harvest) IT produced similar yields, and lower microbial population in lettuce than late IT. After rain, microbial population increased by 1.5 and 3.0 log colony‐forming units (CFU)/g in outer and head leaves respectively. The results revealed the importance of managing moisture conditions at harvest to enhance overall quality of lettuce.
Differentiation of Crude Lipopolysaccharides from Escherichia coli Strains Using Fourier Transform Infrared Spectroscopy and Chemometrics
Authors: Kim Sol , Burgula Y. , Ojanen‐Reuhs Tuula , Cousin Maribeth A. , Reuhs Bradley L. , Mauer Lisa J.
Published: August 2010

Crude phenol‐phase extracts containing bacterial lipopolysaccharides (LPS) from 5 strains of Escherichia coli were investigated to differentiate the strains using Fourier transform infrared (FTIR) spectroscopy and multivariate statistical analysis. The strains used were E. coli K12, E. coli DH5α, E. coli O157:H7, E. coli O157:H12, and E. coli O157:H19. LPS‐containing extracts were isolated from each E. coli strain using a hot phenol‐water extraction procedure. The extracts were 1st analyzed by deoxycholic acid‐polyacrylamide gel electrophoresis and visualized by silver‐staining. Analysis of the extracts from E. coli K12 and E. coli DH5α showed rough‐type LPS on the lower half of the gel, whereas E. coli O157:H7, E. coli O157:H12, and E. coli O157:H19 yielded abundant smooth LPS (high‐molecular‐weight LPS that include the O‐polysaccharides). Spectra (4000 cm‐1 to 700 cm‐1) of crude E. coli LPS extracts and intact cells were collected using a FTIR spectrometer. Spectral data were compressed by principle component analysis and analyzed using canonical variate analysis (CVA) of 4000 cm‐1 to 700 cm‐1 or 1200 cm‐1 to 900 cm‐1 spectral regions. CVA showed better separation between strains using LPS extracts than intact cells in the 1200 cm‐1 to 900 cm‐1 spectral region. The same separation trend was found using Mahalanobis distances that quantified spectral differences between the E. coli strains, providing 80% and >95% correct classifications of intact cells and LPS extracts, respectively. This article is the first to report the successful differentiation of E. coli strains at a serotype level using FTIR spectra of bacterial phenol‐phase extracts (crude LPS preparations).