bluuebunny/crossref_metadata_2025 huggingface dataset:
Shared Graduate Student Education by International Networking
Authors: PURSLOW PETER
Published: August 2010

ABSTRACT: Provision of highly specialized and detailed courses essential for high‐caliber graduate student education often presents a problem of small but essential classes. There are many pitfalls, costs, and successes associated with this problem. For example, meat science is a relatively strong area of research and graduate education in the Nordic countries. Good‐quality Master's level education exists in all countries. The challenge comes in that, in some instances, the class sizes of Master's and PhD courses may be small (3 to 9) with challenges in resource management. Two solutions were considered with the Nordic Forestry, Veterinary and Agricultural Univ. (NOVA), a virtual organization, and the Nordic Network for Meat Science (NNMS). Several major barriers to implement a concerted Master's degree under NOVA related to the realities of resource management and costs. The resource implications effectively meant that the proposed sharing of courses within an existing subject area proved nonviable, although it was recognized that new Master's courses could be constructed on this model. A successful resolution to the problem focused specifically on teaching doctoral level courses. NNMS provides an electronic communication forum, training courses, and an annual workshop for approximately 60 workers in the field with an emphasis on graduate students. The annual workshops allow a relaxed forum where PhD students discuss their work with leaders in their area. NNMS conducts doctoral courses with a very high standard, utilizing both local research expertise of international standing and bringing in well‐known figures from the USA and Australia as guest teachers. Further funding has been successfully obtained against the promise of incorporating the Baltic States (Lithuania, Latvia, and Estonia) into the network.
Promoting the Development of Value‐added Specialty Foods through University‐based Food Venture Centers
Authors: PADILLA‐ZAKOUR OLGA I.
Published: August 2010

ABSTRACT: Food entrepreneurship is a vital part of the food industry that focuses on creating specialty foods from agricultural products. Many entrepreneurial businesses are farm‐based to complement the fresh market with longer shelf‐life value‐added processed foods that utilize products not suited for the fresh market, and excess production that commonly ends up as farm waste/losses. In some cases, the agricultural production is solely dedicated to fulfill the specialty niche market targeted by the small processor. Food entrepreneurs need comprehensive assistance to become successful processors and marketers. As start‐up ventures, their knowledge and economic resources are limited. Support from university‐based food venture centers must include training, counseling, technical services, regulatory compliance assistance, technology transfer, and specialized referrals. The Northeast Center for Food Entrepreneurship, a joint effort of Cornell Univ. and the Univ. of Vermont, is a successful model that benefits from key partnerships to promote food ventures in rural and urban communities. For the last 3 years the center has provided assistance and training to more than 3500 individuals interested in food entrepreneurship, and assisted the development and marketing of over 1000 specialty products. Three examples of farm‐based value‐added enterprises are presented to highlight the center's accomplishments and economic impact.
Contribution of Indigenous Knowledge and Practices in Food Technology to the Attainment of Food Security in Africa
Authors: ONIANG'O RUTH , ALLOTEY JOSEPH , MALABA SERAH J.
Published: August 2010

ABSTRACT: Indigenous knowledge and practices are important aspects of a society's culture and its technology. They include accumulated knowledge, as well as skills and technology of the local people, usually derived from their direct interaction with their local environment. These aspects need due recognition and full understanding and utilization because of the valuable contributions to food security, especially in African communities.Africa's people have traditionally utilized indigenous knowledge, skills and structures, most often locally developed and handed down in the course of centuries. Insufficient attention has been given to this local knowledge within the mainstream food security development and management interventions. However, there is now increasing awareness of the fact that technology includes not only energy sources and tools, but also knowledge and skills, as well as social organizations. It is, therefore, imperative to approach indigenous communities as partners and collaborators in all food security endeavors in order to realize the objective of sustainability. African communities offer a vast array of indigenous knowledge and practices in food technology that are favorable to the food supply, as well as to food quality and food safety and thus directly contribute to food security. As such, indigenous knowledge and practices in food technology that have proved capable of ensuring food security need to be implemented before considering the introduction of external ones if food security is to be realized in Africa. Emphasis of the same should be especially made for foods that are adapted to local conditions thus improving food access, safe food availability, and utilization to meet local and regional needs. This paper seeks to outline the numerous contributions and enormous potentials that indigenous knowledge and practices in food technology have in ensuring food security in Africa.
Trends in Food Science Education in Europe
Authors: DUMOULIN ELISABETH
Published: August 2010

ABSTRACT: In Europe, graduate studies in Food Science have various characteristics: a specific focus or a multi‐disciplinary program among science, engineering, and management; a training period (internship) in industry; and exposure to different languages. A European credit transfer system (ECTS) is used to facilitate exchange of students. The European Union finances the exchange of students and teachers through networks of universities and schools in Europe and with institutions around the world where exchange of teaching methods and scientific information occur. Distance education, continuing education, and opportunities where the student alternates between course work and working in the industry are other modes of education. The organization of Ph. D. programs varies depending on the country. Other initiatives for collaboration with other parts of the world include international Master's programs and courses which prepare students for teaching (for example, courses in curriculum development and pedagogy).
Emulsifying Peptides from the Tryptic Hydrolysis of Casein
Authors: PANYAM D. , KILARA A.
Published: August 2010

ABSTRACT: Casein was hydrolyzed by trypsin to 5% degree of hydrolysis, and the hydrolysate was fractionated by ultrafiltration. While screening for the best emulsifying properties, the retentate fraction was systematically fractionated by ammonium sulfate precipitation, ion exchange, and reverse‐phase high‐performance liquid chromatography (HPLC). Residue from 30% ammonium sulfate saturation yielded 3 fractions on anion exchange chromatography. Preparative reverse‐phase HPLC was used to isolate 4 peptides with good emulsifying properties for characterization. Computational methods were used to complement amino acid sequencing, and the peptides were identified as originating from αs‐1 casein (f167‐208), β‐casein (f48‐63), and (f129‐184). A 4th peptide could not be conclusively identified. Properties of the emulsifying peptides are discussed.
Potential Application of Hot Rehydration Alone or in Combination with Hydrogen Peroxide to Control Pectin Methylesterase Activity and Microbial Load in Cold‐stored Intermediate‐moisture Sun‐dried Figs
Authors: DEMIRBÜKER D. , SIMSEK S. , YEMENICIOGLU A.
Published: August 2010

ABSTRACT: Sun‐dried figs contain a considerable amount of pectin methylesterase (PME) activity (22 JAM COOH/ min/g). The enzyme causes softening and loss of desired gummy texture in cold‐stored intermediate‐moisture (IM) sun‐dried figs brought to a 28% to 29% moisture range. Partial reduction of PME activity (28%) delayed undesirable textural changes in IM figs rehydrated at 80 °C for 16 min. The heat treatment did not cause a considerable reduction in microbial load. However, the addition of 2.5% H2O2 to the rehydration medium at 80 °C reduced the initial total mesophilic aerobic count of figs by at least 90% and turned the figs from a brown color to a desirable and stable yellow‐light brown. The in situ fig catalase remains after rehydration at 80 °C. Thus, by reducing the contact period of figs with H2O2 or by pureeing figs, it is possible to eliminate residual H2O2 and to obtain safe and SO2‐free light‐colored fig products.
Fatty Acid Content and Antioxidant Properties of Cold‐pressed Black Raspberry Seed Oil and Meal
Authors: PARRY J. , YU L.
Published: August 2010

ABSTRACT: Cold‐pressed black raspberry seed oil and meal were analyzed for their fatty acid contents and antioxidant properties. The oil contained about 35%α‐linolenic acid (18:3n‐3) and 55% to 58% linoleic acid. The meal exhibited strong free radical scavenging activities against 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid diammonium salt (ABTS'+) radicals and had a total phenolic content (TPC) of 46 mg gallic acid equivalent/g meal. The ABTS+ scavenging capacity and TPC of the meal were 300 and 290 times greater than that of the oil. In addition, the oil stability iodine value, and color were examined. The results from this study suggest the possible food application of black raspberry seed and its fractions in improving human nutrition and potential value‐adding opportunities in black raspberry production and processing.
Cooked Chicken Breast Meat Conditions Related to Simulated Pink Defect
Authors: HOLOWNIA K. , CHINNAN M. S. , REYNOLDS A. E.
Published: August 2010

ABSTRACT: The objective of this research was to determine the effect of modified in situ conditions on the pink defect in chicken breast meat. Processing plant and replications had no significant effect on the simulation study. Simulation of the pink defect (based on subjective pink threshold) was achieved both with and without sodium nitrite. Simulated pink defect was significantly affected by lightness of raw muscles, increased pH, and decreased oxidation‐reduction potential. The results of this study can lead to establishing a pink threshold for the poultry industry and developing alternate processing methods to eliminate any pink defect.
Water Solubility, Mechanical, Barrier, and Thermal Properties of Cross‐linked Whey Protein Isolate‐based Films
Authors: USTUNOL Z. , MERT B.
Published: August 2010

Water solubility, hermal properties, tensile strength, percent elongation, oxygen permeability (OP), water‐vapor permeability (WVP) of cross‐linked glycerol plasticized whey protein isolate films were studied to determine the effect of cross‐linkers (glutaraldehyde, formaldehyde, dialdehyde starch, carbonyldiimidazole, and UV irradiation) on film properties. With the exception of UV treatment, solubility of the films decreased (P>0.05) upon treatment of the film‐forming solutions with chemical cross‐linkers. Tensile strength increased (P>0.05), whereas percent elongation was not affected by cross‐linking. Chemical cross‐linking increased (P>0.05) WVP and decreased (P>0.05) OP of the films. UV treatment had no effect on WVP and O P. With the exception of UV‐treated films, both onset temperature and degradation temperatures, as determined by differential scanning calorimetry, were increased upon cross‐linking.
A New Approach to Predict the Water‐transport Properties of Multilayer Films Intended for Food‐packaging Applications
Authors: NOBILE M. A. DEL , BUONOCORE G. G. , DAINELLI D. , NICOLAIS L.
Published: August 2010

ABSTRACT: A mathematical model that predicts the water‐permeability coefficient of multilayer films intended for food‐packaging applications is presented. A 6‐layer film composed of 5 polyolefinic layers and a layer made of a copolymer of ethylene and vinylalcohol (EVOH) was used to validate the proposed model. Water‐permeability tests were run at 25°C both on each single layer and on the multilayer film; whereas the water‐sorption isotherm and the water‐sorption kinetics were determined only for the EVOH layer. Results suggest that the water‐permeability coefficient of multilayer films can be predicted from the knowledge of the water‐transport properties of each constituent layer.
Dehydration Techniques Affect Phytochemical Contents and Free Radical Scavenging Activities of Saskatoon berries (Amelanchier alnifolia Nutt.)
Authors: KWOK B. H. L. , HU C. , DURANCE T. , KITTS D. D.
Published: August 2010

ABSTRACT: Saskatoon berries (Amelanchier alnifolia Nutt., cv. Thiessen and Smoky) were dehydrated using freeze‐drying (FD), vacuum microwave drying (VMD), air‐drying (AD), and a combination of air‐drying and vacuum microwave drying (CD) methods. All processed berries had significantly reduced (P < 0.05) total phenolics and anthocyanin contents in addition to reduced antioxidant activities, as compared with fresh frozen (FF) berries. FD berries rendered the highest amount (P < 0.05) of anthocyanin and antioxidant activities, followed by VMD berries. The CD dehydration resulted in intermediate results between VMD and AD. The substantial decrease in both total phenolics and anthocyanin content in berries was corresponded to significant (P < 0.05) losses in antioxidant capacities measure in different model systems.
Volatiles and Flavor of Five Turkish Hazelnut Varieties as Evaluated by Descriptive Sensory Analysis, Electronic Nose, and Dynamic Headspace Analysis/Gas Chromatography‐Mass Spectrometry
Authors: ALASALVAR C. , ODABASI A. Z. , DEMIR N. , BALABAN M. Ö. , SHAHIDI F. , CADWALLADER K. R.
Published: August 2010

ABSTRACT: Forty‐six volatile compounds were detected by gas chromatography‐mass spectrometry, with 31 being positively identified in all hazelnuts (6 tentative and 9 unknown). Çakildak variety contained the highest content of total volatiles, followed by Palaz, Mincane, Fosa, and Tombul, with no significant differences (P>0.05) between Tombul, Fosa, and Mincane. In total, 39, 37, 36, and 31 volatile compounds were determined for the 1st time in Tombul, (Çakildak and Mincane), Fosa, and Palaz, respectively. Descriptive sensory analysis showed that intensities of 7 flavor attributes had no significant differences (P > 0.05) among Tombul, Fosa, and Mincane. In contrast, Çakildak was rated as being significantly (P < 0.01) lower in most flavor attributes. Discriminant function analysis on the electronic nose (E‐nose) sensor data resulted in 100% correct classification of the samples into their respective varieties. Certain E‐nose sensor types correlated well with some volatile compounds.
Optimization of Medium Composition for Cultivating Clostridium butyricum with Response Surface Methodology
Authors: Kong Qing , HE Guoqing , Chen Qihe , Chen Feng
Published: August 2010

ABSTRACT: Probiotic bacteria, such as some strains of Clostridium butyricum, have been frequently used as the active ingredient in functional foods. However, slow growth of the probiotic bacteria has been one of the big concerns for their potential commercial application. In the present study, a fractional factorial design was applied to investigate the main factors, namely, the concentrations of the glucose, tryptone, yeast extract, beef extract, cys‐teine, (NH4) 2SO4, NaCl, K2HPO4, and the medium initial pH that affected the growth of 1 probiotic strain, C. butyricum ZJUCB, currently preserved in our laboratory. Central composite experimental design and response surface methodology were adopted to derive a statistical model for optimizing the composition of the medium. The experimental results showed that the optimum medium for incubating the C. butyricum ZJUCB was composed of 2.44% (w/v) glucose, 2.08% yeast extract (w/v), 1% tryptone (w/v), 0.1% (NH4)2SO4 (w/v), 0.1% NaHCO3 (w/v), 0.02% MnSO4. H2O (w/v), 0.02% MgSO4. 7H2O (w/v), 0.002% CaCl2 (w/v), and 2% agar (w/v) (if necessary) at pH 8.55. After incubation for 24 h in the optimum medium, the populations of the viable organisms could reach 109 colony‐forming units (CFU)/mL, which was 100 times higher than that incubated in the initial medium.
Fat Migration in Chocolate: Diffusion or Capillary Flow in a Particulate Solid?—A Hypothesis Paper
Authors: Aguilera J. M. , Michel M. , Mayor G.
Published: August 2010

ABSTRACT: The exact mechanism of fat and oil migration in chocolate and chocolate coatings is still unknown. Nevertheless, the so‐called “diffusion equation” derived from Fick's 2nd law has been extensively used to model the phenomenon, giving the impression that molecular diffusion is the single transport mechanism. We propose that chocolate may be microstructurally regarded as a particulate medium formed by an assembly of fat‐coated particles (for example, cocoa solids, sugars crystals, and milk powder). Within this matrix the liquid fraction of cocoa fat (which increases with temperature) is likely to move under capillary forces through interparticle passages and connected pores. Based on available evidence (microstructure, kinetic data, temperature dependence of liquid fat fraction, and so on) we demonstrate that capillary forces may have an important role to play in bulk flow of liquid fat and oils. The Lucas‐Washburn equation for capillary rise fits available data under most reported experimental conditions. Detailed microstructural analysis in actual products as well as data on key parameters (surface tension, contact angle, viscosity) is necessary to confirm this hypothesis. Bulk flow due to capillary effects, highly disregarded in structured foods, should be considered as a mass transfer mechanism in liquid‐filled porous or particulate foods.
Texture Analysis of Taro (Colocasia esculenta L. Schott) Cormels during Storage and Cooking
Authors: Sajeev M. S. , Manikantan M. R. , Kingsly A. R. P. , Moorthy S. N. , Sreekumar J.
Published: August 2010

ABSTRACT: Textural characteristics of taro (Colocasia esculenta L. Schott) cormels during storage at tropical ambient conditions (31.8 to 44.9 °C, 30% to 50% relative humidity [RH]), evaporative cooled room (EC room) (26.2 to 33.9 °C, 59% to 92% RH), and refrigerator (10 °C, 65% RH) and cooking were measured under compression/penetration and cutting modes. After 20 d of storage, physiological loss in weight was maximum at ambient condition followed by EC room and refrigerated condition. The textural parameters (that is, hardness, toughness, cutting force, and cutting energy) significantly increased with storage period whereas effect of storage condition was significant only for toughness and cutting energy (P < 0.001). Most of the rheological characteristics were lowered for the flours prepared from the stored samples. Fractional conversion technique and time step effect parameters were employed to model the kinetics of texture degradation during cooking. The mode of measurement of texture characteristics influenced the kinetic model, that is, cutting force, was described with 1st‐order kinetic model and hardness by dual mechanism of 1st order.
Sequential Quadratic Programming for Development of a New Probiotic Dairy Tofu with Glucono‐δ‐Lactone
Authors: Chen M.‐J. , Chen K.‐N. , Lin C.‐W.
Published: August 2010

ABSTRACT: The purpose of this research was to evaluate the effects of various concentrations of glucono‐δ‐lactone (GDL) and skim milk powder, as well as the addition of prebiotics, on the rheology and probiotic viabilities of dairy tofu. Additionally, modern optimization techniques were applied to attempt to determine the optimal processing conditions and growth rate for the selected probiotics (Lactobacillus. acidophilus, L. casei, Bifidobacteria bifidum, and B. longum). There were 2 stages in this research to accomplish the goal. The 1st stage was to derive surface models using response surface methodology (RSM); the 2nd stage performed optimization on the models using sequential quadratic programming (SQP) techniques. The results were demonstrated to be effective. The most favorable production conditions of dairy tofu were 1% GDL, 0% peptides, 3% isomaltooligosaccharides (IMO), and 18% milk, as confirmed by subsequent verification experiments. Analysis of the sensory evaluation results revealed no significant difference between the probiotic dairy tofu and the GDL analog in terms of texture and appearance (P < 0.05). The viable numbers of probiotics were well above the recommended limit of 106 CFU/g for the probiotic dairy tofu throughout the tested storage period.
Fractionation and Characterization of the Macromolecular Meaty Flavor Enhancer from Beef Meat Extract
Authors: Kuroda M. , Harada T.
Published: August 2010

ABSTRACT: Macromolecular meaty flavor enhancer was fractionated from a commercial beef extract. The macromolecular fraction was obtained by dialysis and separated by anion‐exchange chromatography, Cu2+‐chelate chromatography, and gel filtration chromatography. Two fractions were isolated as active meaty flavor enhancers. To elucidate the partial structures, the active fractions were treated with endoprotease Glu‐C followed by high‐performance liquid chromatography (HPLC) separation of the peptide fragments. Determinations of the amino acid compositions and amino acid sequences of the isolated fragments showed that the 2 active fractions consisted of collagen and tropomyosin. The macromolecular material obtained from heated collagen and tro‐pomyosin in the low‐molecular‐weight fraction of beef soup stock enhanced the meaty flavor. These results suggested that collagen and tropomyosin were precursors of the macromolecular meaty flavor enhancer.
Selection and Use of Postharvest Technologies as a Component of the Food Chain
Authors: BOURNE MALCOLM C.
Published: August 2010

ABSTRACT: Postharvest technologies refer to the stabilization and storage of unprocessed or minimally processed foods from the time of harvest until final preparation for human consumption. There is a special emphasis on seasonal crops, and simple, labor‐intensive, capital‐sparing technologies suitable for developing countries where food spoilage rates are high and malnutrition is prevalent. The first step is to determine the major spoilage vectors for each type of food and then identify a technology that will control that vector. For cereal grains the major spoilage vectors are mold, insects, rodents, and other vertebrate pests. Mold is controlled by prompt and adequate drying to a water activity below 0.7. Insects are controlled by good housekeeping, and use of insecticides and fumigants. Rodents are controlled by baits, traps, fumigants, and rodent‐proof storage structures. For fruits, vegetables, roots, and tubers the main spoilage vectors are bruising, rotting, senescence, and wilting. Bruising is avoided by careful handling and use of shock‐resistant packaging. Rotting is controlled by good housekeeping, gentle handling to avoid breaking the skin, cool storage, and use of preservatives. Senescence is retarded by cold storage or controlled‐atmosphere storage. Wilting is controlled by high humidity and cold storage. Growth of microbes is the major spoilage of fish and other foods of animal origin. This is controlled by refrigerated or frozen storage, drying, freezing, or canning. Most spoilage vectors accelerate as the temperature and humidity increase; this makes it more difficult to control spoilage in tropical than in temperate regions.
Physicochemical and Volatile Characterization of Structured Lipids from Olive Oil Produced in a Stirred‐tank Batch Reactor
Authors: LEE J. H. , KIM M. R. , KIM I. H. , KIM H. , SHIN J. A. , LEE K. T.
Published: August 2010

ABSTRACT: Structured lipid (SL) from conjugated linoleic acid (CLA) with olive oil was produced, and the physicochemical and volatile characterizations were investigated. In SL‐olive oil, 21.8 mol% of CLA isomers were incorporated, and the removal of tocopherols (63% loss from original olive oil) and chlorophylls (50% loss) was observed. The distinct exothermal peaks observed became broader, and the position of the peak shifted to a lower temperature in SL‐olive oil compared with normal olive oil. Reverse‐phase (ODS column) high‐performance liquid chromatography with an evaporative light‐scattering detection separated the newly synthesized SL‐triacylglycerols (TAGs), in which the incorporation of CLA into olive oil increased the content of TAGs with partition number <48 from 9% (in olive oil) to 78% (SL‐olive oil). Total amount of volatile compounds in SL‐olive oil was smaller than those in olive oil, indicating removal of flavor compounds from olive oil occurred during the processes.
Effect of Processing and Storage on Antioxidant Capacity of Honey
Authors: WANG X. H. , GHELDOF N. , ENGESETH N. J.
Published: August 2010

ABSTRACT: The impact of heat and filtration on the antioxidant capacity of clover and buckwheat honey during storage was analyzed. Processing clover honey did not significantly impact antioxidant capacity (determined by oxygen radical absorbance capacity [ORAC] assay); processing lowered the antioxidant capacity of buckwheat honey (33.4%). The antioxidant capacity of honeys was reduced after 6 mo of storage with no impact of storage temperature or container type detected at the end point of the storage period. Processed and raw clover honey antioxidant capacity decreased about 30%. Processed buckwheat honey decreased 24% in antioxidant capacity, whereas raw buckwheat honey decreased 49%. Antioxidant capacity of processed and raw honeys was similar after storage. Phenolic profiles, peroxide accumulation, 5‐(hydroxymethyl)‐2‐furaldehyde (HMF), gluconic acid, and total phenolics were also analyzed. The impact of storage on antioxidant components of processed and raw honey was complex.
Whey Protein Isolate and α‐Lactalbumin Recovery from Lactic Acid Whey Using Cation‐Exchange Chromatography
Authors: Turhan K. N. , Etzel M. R.
Published: August 2010

ABSTRACT: The objective of this work was to develop a process to fractionate proteins from lactic acid whey, which is underused compared with sweet whey, using food‐grade buffers and cation‐exchange chromatography. Bound proteins were desorbed either all at once to make whey protein isolate (WPI), or in 2 steps to 1st make α‐lactalbumin (ALA) and then WPI depleted in ALA. Recovery and purity using lactic acid whey were comparable to previously reported processes using sweet whey. Capacity and throughput were slightly lower using lactic acid whey. This research provides a basis for adding value to the 6 million metric tons of lactic acid whey produced annually in the United States.
Ohmic Cooking of Processed Meats and its Effects on Product Quality
Authors: Piette G. , Buteau M.L. , de Halleux D. , Chiu L. , Raymond Y. , Ramaswamy H.S. , Dostie M.
Published: August 2010

ABSTRACT: A basic bologna emulsion (lean and fatty pork meat, sodium chloride, sodium erythorbate, and sodium nitrite) was cooked in 1‐kg portions, either in a smokehouse (180‐min cycle; to 70 °C at core) or by ohmic heating (64 to 103 V; 3.9 °C/min to 10.3 °C/min; to 70 °C to 80 °C), and the finished products were compared for color, texture, pH, drip, Eh, and rancidity. Heating rates, final temperatures, and a 20‐min holding time had little influence on the quality of ohmic sausages. In addition, ohmic sausages were always found to be similar to smokehouse products except for texture, which was significantly softer (P > 0.05) in ohmic products but could be hardened by use of binders.
Effect of Cell Wall Degrading Enzymes on In Vitro Carotene Accessibility in Lactic Acid Fermented Carrot Beverage
Authors: Díaz V. , HedrÉn E. , Ruales J. , Svanberg U.
Published: August 2010

ABSTRACT: Carrot purées with different particle size were prepared from fresh carrots using 2 different food processors. The purées were fermented with lactic acid bacteria (Lactobacillus plantarum) with and without addition of cell wall degrading enzymes (Pectinex® Ultra SP‐L and CellubrixTM L). The bioaccessibility of carotenes was estimated using an in vitro digestion method. In carrots processed to a particle size <1.5 mm, the in vitro β‐carotene accessibility was 46% and neither fermentation nor addition of cell wall‐degrading enzymes had any further effect on the in vitro accessibility. In carrot purées with a coarser particle size, the in vitro β‐carotene accessibility was 18%; that significantly increased by adding high amounts of cellulases or pectinases or a combination of the enzymes either in low or high amounts. The improved accessibility was correlated with reduced particle size of the carrot purée.
Effect of Slaughter Method on Postmortem Changes of Grass Carp (Ctenopharyngodon idella) Stored in Icesti
Authors: Scherer Rodrigo , Augusti Paula R. , Steffens Camila , Bochi Vivian C. , Hecktheuer Luisa H. , Lazzari Rafael , Radünz‐neto Joao , Pomblum Solange C.G. , Emanuelli Tatiana
Published: August 2010

ABSTRACT: The effect of 2 slaughter methods (immersion in ice‐water slurry and electrical stunning followed by ice slurry asphyxiation) on the quality of grass carp (Ctenopharyngodon idella) stored in ice for 20 d was evaluated using sensory and chemical analysis. Electricity immediately stunned the fish and did not induce blood spots in the flesh. Fish killed by electricity showed a faster initial rate of ATP degradation and entered into rigor mortis earlier, but did not show significant differences in the sensory score when compared with fish killed by immersion in ice‐water slurry. Thus, no differences were observed in the shelf life of carps between the 2 slaughter methods evaluated. The limit for acceptability of grass carp stored in ice was around 13 to 16 d. Grass carp accumulated more inosine than hypoxanthine. K, Ki, P, Fr, and H values were highly correlated with storage time and with the TFRU sensory scores in both groups; these could be used to assess the freshness quality of grass carp.
Effect of Vacuum and Modified Atmosphere Packaging on the Shelf‐life of Liquid‐smoked Swordfish (Xiphias gladius) Slices
Authors: Muratore Giuseppe , Licciardello Fabio
Published: August 2010

ABSTRACT: Swordfish fillets, dry‐salted and treated with liquid smoke, were sliced and packed in vacuum conditions and under modified atmosphere (MA) (5% O2,45% CO2, 50% N2) and stored at chilled temperature (4°C) to determine the effect of different packaging on shelf‐life. Sensory attributes, total volatile basic nitrogen (TVB‐N), pH, lipid oxidation by thiobarbituric acid test, and microbiological counts were monitored during 45 d of storage. The TVB‐N increased to levels recommended by European regulation at the time of sensory rejection, resulting as the most reliable parameter of quality decay. Lipid oxidation was low and microbial counts could not be correlated with quality decay. Sensory rejection (at least 50% of the assessors scoring =5 in a scale from 1 to 9) was sooner for MA‐packed samples (12d) than for vacuum‐packed ones (42d).
Does Electroporation Occur During the Ohmic Heating of Food?
Authors: Lebovka Nikolai I. , Praporscic I. , Ghnimi S. , Vorobiev Eugene
Published: August 2010

ABSTRACT: The effect of temperature on electroporation of plant tissues during the pulsed electric field (PEF) or alternative current (AC) treatment was studied. The characteristic damage time t, which determines effectiveness of the electroporation mechanism in plant tissue damage, was estimated for potatoes tissues in the range of electric field strengths E= 40 to 500 V/cm and at temperatures T= 22°C and T= 49 °C in PEF treatment experiments. Experimental results of the AC ohmic heating of potato and apple tissues are evidence of the importance of the electroporation mechanism of tissue damage at moderate electric fields (MEF), when the electric field strength E is under 100 V/cm, and show that effectiveness of this mechanism increases with temperature increase.
Oil Migration in a Chocolate Confectionery System Evaluated by Magnetic Resonance Imaging
Authors: Choi Young J. , McCarthy Kathryn L. , McCarthy Michael J.
Published: August 2010

ABSTRACT: Oil migration is a common problem in composite chocolate confectionery products resulting in softening of chocolate and hardening of the filling. Spatial and temporal changes in the liquid oil content of a 2‐layer peanut butter and chocolate model system were evaluated using a magnetic resonance imaging (MRI) technique. The experimental factors were chocolate particle size, milk fat content, emulsifier concentration, degree of temper, and storage temperature. The responses were migration rate and overall change in signal intensity (amount of migration). Based on analysis of variance (ANOVA), particle size, milk fat content, and storage temperature were significant factors for oil migration rates. Milk fat content and temperature were significant factors for overall change in signal intensity.
Drying Kinetics ofCurcuma longaRhizomes
Authors: Mulet Antonio , Blasco Miguel , García‐Reverter José , García‐Pérez Josév.
Published: August 2010

ABSTRACT:Modeling drying kinetics is very useful for optimization purposes. Hot air drying kinetics were carried out in monolayer at different temperatures (60°C, 70°C, 80°C, 90°C, and 100°C) and for different sample types (peeled and unpeeled rhizomes of different sizes). Mathematical models based on Fick's law were used to describe water removal, considering different boundary conditions and geometries. Effective moisture diffusivities identified from modeling presented an Arrhenius‐type relationship. An additional mass transfer resistance was identified as due mainly to the peridermis layer (peridermial resistance). The accuracy of the model assuming peridermial resistance only in the radial direction and solved using the finite differences method was illustrated, and the mass transfer coefficient was identified (k = 9.7 × 10‐5kg water/m2/s). Keywords:Curcuma longa, drying, modeling, peridermial resistance
Crystallization Kinetics and X‐ray Diffraction of Crystals Formed in Amorphous Lactose, Trehalose, and Lactose/Trehalose Mixtures
Authors: Miao Song , Roos Yrjö H.
Published: August 2010

ABSTRACT: Effects of storage time and relative humidity on crystallization kinetics and crystal forms produced from freeze‐dried amorphous lactose, trehalose, and a lactose/trehalose mixture were compared. Samples were exposed to 4 different relative water vapor pressure (RVP) (44.1%, 54.5%, 65.6%, 76.1%) environments at room temperature. Crystallization was observed from time‐dependent loss of sorbed water and increasing intensities of peaks in X‐ray diffraction patterns. The rate of crystallization increased with increasing storage humidity. Lactose crystallized as α‐lactose monohydrate, β‐anhydrous, and anhydrous forms of α‐ and β‐lactose in molar ratios of 5:3 and 4:1 in lactose and lactose/trehalose systems. Trehalose seemed to crystallize as a mixture of trehalose dihydrate and anhydrate in trehalose and lactose/trehalose systems. The crystal forms in a mixture of lactose and trehalose did not seem to be affected by the component sugars, but crystallization of the component sugars was delayed. Time‐dependent crystallization of lactose and trehalose in the lactose‐trehalose mixture could be modeled using the Avrami equation. The results indicated that crystallization data are important in modeling of crystallization phenomena and predicting stability of lactose and trehalose‐containing food and pharmaceutical materials. Keywords: crystallization, lactose, trehalose, crystal form, X‐ray diffraction
Biosynthesis of 1‐Octen‐3‐ol and 10‐Oxo‐trans ‐8‐decenoic Acid Using a Crude Homogenate of Agaricus bisporus: Reaction Scale Up
Authors: Morawicki Ruben O. , Beelman Robert B. , Petreson Devin , Demirci Ali
Published: August 2010

ABSTRACT: The enzymatic reaction that produces 1 ‐octen‐3‐ol and 10‐oxo‐trans‐8‐decenoic acid was successfully scaled up from a 1 ‐L to a 10‐L bioreactor using a crude mushroom homogenate of Agaricus bisporus. For this non‐Newtonian reaction broth, the agitation rate was considered the most important controlling factor for the scale up. An agitation rate of 600 rpm, for an aeration rate of 0.44 m3/m3/h, was found to be the minimum to maintain the yield constant for the 1‐L reactor. Subsequently, the agitation rate for the 10‐L reactor was determined using 2 different approaches: a constant power per volume of liquid and a constant volumetric mass transfer coefficient (kLa). The constant power per volume of liquid approach predicted an agitation rate of 364 rpm that resulted in being too low to maintain the same yield obtained with the 1‐Lreactor. Measurement of the kLa for the 10‐Lreactor, at 364 rpm and an aeration of 0.44 m3/m3/h, produced a value of 11.7/h, thus confirming that the reaction in the larger reactor was oxygen‐deprived. Therefore, the use of constant volumetric mass transfer coefficient (kLa) strategy was used instead. kLa was experimentally determined at different agitation rates for the 10‐L reactor. It was found that 750 rpm produced a kLa of 40.2/h. Confirmatory reactions were run in both reactors with the same batch of mushrooms, and the results were equivalent, thus indicating that was a good criterion for scaling up this process.
Inactivation of Listeria monocytogenes on Beef Bologna and Cheddar Cheese Using Polyvinyl‐idene Chloride Films Containing Sorbic Acid
Authors: Limjaroen Paweena , Ryser Elliot , Lockhart Hugh , Harte Bruce
Published: August 2010

ABSTRACT: Polyvinylidene chloride (PVDC, SaranR F‐310) films containing sorbic acid (0%, 1.5%, and 3.0% w/v) were prepared with use of a solvent‐casting method and were then placed between slices of commercially produced beef bologna that were previously surface‐inoculated with L. monocytogenes at 103 or 105 CFU/g. In addition, cubes of commercial Cheddar cheese were surface‐inoculated to contain 103 or 105Listeria monocytogenes colony‐forming units (CFU) /g and then wrapped with the sorbic acid‐containing films. Films containing 1.5% and 3.0% (w/ v) sorbic acid prevented growth of L. monocytogenes on bologna slices with populations as much as 7.1 logs lower after 28 d of storage at 4 °C compared with the sorbic acid‐free controls. In contrast, numbers of Listeria remained relatively stable on Cheddar cheese with populations decreasing < 1.3 logs after 35 d of storage. With use of the sorbic acid‐containing films, common spoilage organisms were also inhibited on both products. After 28 d of contact with bologna and Cheddar cheese, these films retained 7% and 60% of their original sorbic acid content, respectively, with the control film retaining 85% of its original sorbic acid content. Given these findings, sorbic acid‐containing films may be useful in enhancing the safety and shelf‐life of ready‐to‐eat delicatessen products.
Effect of Heat Processing on the Texture Profile of Canned and Retort Pouch Packed Oil Sardine (Sardinella longiceps) in Oil Medium
Authors: Ali Ansar , Sudhir B. , Srinivisa Gopal Teralandur K.
Published: August 2010

ABSTRACT: Sardine in oil was canned at 3 different Lethality values (F0 5,7, and 9) in retort pouches and aluminum cans in stationary retort. Process time calculations were done mathematically to find out the actual process time. Sardine in oil processed in retort pouches had a lower process time compared with aluminum cans for each F0 value. Instrumental texture analysis was done using a food texture analyzer to study the effect of thermal processing on the texture of thermally processed sardine in oil in aluminum cans and retort pouches. As the F0 value and cook value increased in both the retort pouches and aluminum cans, the textural properties showed a decreasing trend. Hardness of the product canned in both aluminum cans and retort pouches decreased with increase in F0 values.
Lipase‐catalyzed Transesterification of Medium‐chain Triacylglycerols and a Fully Hydrogenated Soybean Oil
Authors: Lopez‐Hernandez Arnoldo , Garcia Hugo S. , Hill Charles G.
Published: August 2010

A commercial preparation of medium‐chain TAG (MCT) was enzymatically transesterified with a fully hydrogenated soybean oil (FHSBO) at different weight ratios (40:60, 50:50, 60:40, and 70:30). All reactions were carried out at 70 °C in flasks placed in an orbital shaker (300 rpm). Three different lipase preparations were tested: TLIM (Thermomyces lanuginosus), lipase PS (Burkholderia cepacia), and Chirazyme L2 (Candida antarctica). The progress of the reaction was monitored by following the changes in the triacylglycerol (TAG) profile of the reaction mixture with reversed‐phase high‐performance liquid chromatography (HPLC). The rates of disappearance of the TAG originally present in both the MCT and the FHSBO were fastest when lipase TL IM was used; the slowest rates were observed for lipase PS. Although the relative compositions of the newly formed TAG at equilibrium depended on the particular lipase used and the initial weight ratio of the substrates, the TAG families containing 2 stearic residues and a residue of either capric acid or caprylic acid were the most abundant product species. All samples were analyzed by differential scanning calorimetry (DSC) to determine the effect of this reaction on the melting profile of the resulting products.
Functional and Thermal Properties of Wheat, Barley, and Soy Flours and Their Blends Treated with a Microbial Transglutaminase
Authors: Ahn H.J. , Kim J.H. , Ng P. K.W.
Published: August 2010

The effects of transglutaminase (TG) on the functional and thermal properties of wheat, barley, and soy flours and their blends were investigated. Free amino and thiol groups and aromatic hydrophobicity in samples were decreased with TG treatment (P < 0.05), confirming the polymerization of proteins in flours by TG treatment. TG‐treated samples had increased water‐holding capacity, fat adsorption, and emulsion stability, and slightly decreased emulsion activity. The addition of barley or soy to wheat flours decreased fat adsorption and emulsion stability, but these values increased, upon TG treatment of the same blended samples, to levels as high as for untreated wheat alone. TG treatment did not significantly affect the transition peak temperature of the flour samples. However, TG treatment lowered the transition enthalpy of wheat blended with barley or soy flour, and, conversely, increased that of wheat flour samples alone. Results suggest that protein cross‐linking by TG can produce unique and improved functionality even in wheat blended with barley or soy flour, and could provide opportunities for exploitation of this enzyme for product development.
Effects of Alkaline and Acid Pretreatments on Alaska Pollock Skin Gelatin Extraction
Authors: Zhou Peng , Regenstein Joe M.
Published: August 2010

Pretreatments with different alkalis and acids at different concentrations were used to determine their effects on gelatin extraction from Alaska pollock skin. The alkaline pretreatments with the OH concentrations lower than 0.5 mol/L removed noncollagenous proteins without significant loss of skin collagen. The acid pretreatments caused loss of collagen, even using a weak acid with a low H concentration at a low temperature. The presence of proteases might cause degradation of gelatin extract, but the pretreatments with NaOH or Ca(OH)2 at 0.1 mol/L OH concentration, or acetic acid at 0.05 mol/L H concentration could significantly decrease the degradation by proteases. The combination of an alkaline pretreatment followed by an acid pretreatment not only removed the noncollagenous proteins, but also provided the proper pH condition for extraction, during which some cross‐linkages could be further destroyed but with less breakage of polypeptide chains.
Volatile Compounds and Chemical Changes in Ultrapasteurized Milk Packaged in Polyethylene Terephthalate Containers
Authors: Solano‐Lopez Claudia E. , Ji Taehyun , Alvarez Valente B.
Published: August 2010

The volatile compounds profile and chemical stability of ultrapasteurized 2% milk bottled in amber polyethylene terephthalate (PET) were studied along with its shelf life of 60 d at 5 °C. Identification of volatile compounds using a solid‐phase microextraction (SPME) technique with gas chromatography‐mass spectrometry was performed in situ in the commercial product. Chemical stability was determined by measuring dissolved oxygen, free sulfhydryl groups, ascorbic acid, and headspace oxygen. The classes of volatile compounds identified were ketones, aldehydes, hydrocarbons, fatty acids, alcohol, and miscellaneous compounds. Volatile compounds found consistently during the storage period were 2‐heptanone, methoxy‐phenyl‐oxime, decane, 1‐ethyl‐2,4‐dimethyl‐benzene, D‐limonene, 2‐nonanone, octanoic acid, dodecane, and 4‐(1,1,3,3, ‐tetramethylbutyl) phenol. Possible products of lipid oxidation, such as hexanal, octanal, and nonanal, were also positively identified. Chemical stability of PET‐bottled milk was demonstrated by the insignificant changes in pH or TA, with the exception of ascorbic acid concentration, which degraded in the product at 60 d of refrigerated storage. Sensory evaluation of the milk samples revealed that there is no noticeable oxidized or rancid off‐flavor at 60 d of storage.
Physiology and Microbiological Quality of Fresh‐cut Mango Cubes as Affected by High‐O2 Controlled Atmospheres
Authors: Poubol Jutatip , Izumi Hidemi
Published: August 2010

Preliminary study showed that among 40‐ to 100‐kPa O2 atmospheres, 60‐kPa O2 reduced the respiration of fresh‐cut ‘Carabao’ mango cubes the most when held at 5 °C or 13 °C for 42 h. Therefore, the effects of 60‐kPa O2 on the physiology and microbial quality of fresh‐cut ‘Carabao’ and ‘Nam Dokmai’ mango cubes were determined and compared with those held in air. The high‐O2 atmosphere reduced the respiration rate of ‘Carabao’ mango cubes stored at 5 °C but stimulated the rate after 2 d of storage at 13 °C. Browning of ‘Carabao’ cubes was accelerated by 60‐kPa O2 at 13 °C. With ‘Nam Dokmai’ cubes, the high O2 had no effect on respiration rate, browning, and incidence of water‐soaked appearance at 5 °C and 13 °C. The high O2 did not affect texture or ascorbic acid content of ‘Carabao’ and ‘Nam Dokmai’ mango cubes at either temperature. Counts of lactic acid bacteria and molds were below the detection level (2.4 log colony‐forming units [CFU]/g) during storage at both temperatures. However, 60‐kPa O2 stimulated the growth of mesophilic aerobic bacteria on ‘Carabao’ cubes and yeasts of ‘Nam Dokmai’ cubes at 13 °C. The increased microbial count may have been due to the higher pH of cubes stored in 60‐kPa O2 at 13 °C than at 5 °C or in air. Within ‘Nam Dokmai’ mango cubes, the predominant genera in mesophilic aerobic bacteria were Enterobacter, Klebsiella, and Pantoea and in the yeasts were Candida, Cryptococcus, and Rhodotorula. These results indicate that 60‐kPa O2 is not desirable for mango cubes when held at 13 °C.
Microbiological Characteristics of Enhancement Solutions
Authors: Wicklund S.E. , Stetzer Aj , Tucker E.M. , Nicolalde C.L. , Brewer M.S.
Published: August 2010

The objective of this study was to assess the survival of Escherichia coli K‐12 in solutions of ingredients used for enhancing meat products and to evaluate the effect of potentially lethal temperatures. Enhancement solutions were prepared to contain water only (W); water + salt + phosphate (control, C); water + salt + phosphate + sodium lactate (SL); water + salt + phosphate + sodium acetate (SA); or water + salt + phosphate + lactate + diacetate (SLDA). The SLDA solution resulted in the highest log reduction of E. coli K‐12 followed by SL. Heating solutions to 70 °C resulted in about a 4 log reduction, whereas heating to 60 °C produced about a 2 log reduction. For samples with an initial microbial load of 106 colony‐forming units (CFU)/mL, addition of SL and heating to 50 °C resulted in about a 2 log reduction, addition of SA gave <0.5 log reduction, whereas addition of the SLDA combination produced a > 4.0 log reduction. The SLDA combination could allow for lower heating temperatures to achieve similar microbial reductions.