bluuebunny/crossref_metadata_2025 huggingface dataset:
Nondestructive Monitoring of Oxygen Profiles in Packaged Foods Using Phase‐Fluorimetric Oxygen Sensor
Authors: Fitzgerald M. , Papkovsky D.B. , Smiddy M. , Kerry J.P. , O'Sullivan C.K. , Buckley D.J. , Guilbault G.G.
Published: August 2010

ABSTRACT: Nondestructive quantitation of oxygen in different types of packaged foods was performed using disposable phosphorescent oxygen sensor inserts placed in every individual sample and a fiber‐optic phosphorescent phase detector. Oxygen levels and their changes over storage time are presented for vacuum‐packed raw and cooked meat, smoked fish, and MAP sliced ham and bread. Damage to vacuum‐packages was simulated by slitting the package film and monitoring the sensor response at different locations from the site of damage. The performance of the optical oxygen sensor in packaged foods was evaluated, and its usefulness for food research and industrial applications discussed.
Comparison of the Emulsifying Properties of Fish Gelatin and Commercial Milk Proteins
Authors: Dickinson E. , Lopez G.
Published: August 2010

ABSTRACT: We have compared the flocculation, coalescence, and creaming properties of oil‐in‐water emulsions prepared with fish gelatin as sole emulsifying agent with those of emulsions prepared with sodium caseinate and whey protein. Two milk protein samples were selected from 9 commercial protein samples screened in a preliminary study. Emulsions of 20 vol%n‐tetradecane or triglyceride oil were made at pH 6.8 and at different protein/oil ratios. Changes in droplet‐size distribution were determined after storage and centrifugation and after treatment with excess surfactant. We have demonstrated the superior emulsifying properties of sodium caseinate, the susceptibility of whey protein emulsions to increasing flocculation on storage, and the coalescence of gelatin emulsions following centrifugation.
Microbial Quality of Alfalfa Seeds and Sprouts after a Chlorine Treatment and Packaging Modifications
Authors: Soylemez G. , Brashears M.M. , Smith D.A. , Cuppett S.L.
Published: August 2010

ABSTRACT: Alfalfa seeds were treated with chlorine to determine the effect on microbial populations during soaking, sprouting, and refrigerated storage in three packaging environments. Chlorine was effective in reducing microbial populations on the seeds, but numbers increased during sprouting. Chlorine treatments had the most impact on yeast and molds during storage. Yeast and molds were significantly higher in sprouts that were stored in vacuum packages and in sprouts from non‐chlorine treated seeds stored in MAP. Yeast and mold counts on all sprouts stored in perforated packaging did not significantly increase during storage. A combination of chlorine treatment of the seeds and preforated packaging of sprouts may increase the shelf‐life.
Hen Egg Yolk Prevents Bacterial Adherence: A Novel Function for a Familiar Food
Authors: Deignan T. , Alwan A. , Malone L. , Kelly J. , O'Farrelly C.
Published: August 2010

ABSTRACT:The aim of this study was to evaluate the ability of unfractionated hen egg yolk to prevent the attachment ofSalmonella typhimuriumto murine intestinal epithelial cells in vitro. Inhibition of adherence was examined microscopically and by an ELISA. Both methods showed that egg yolk from immunized and unimmunized hens significantly reduced bacterial adherence. Optical density (OD) readings ± SD of 0.825 ± 0.016 for untreated bacteria were reduced to 0.335 ± 0.024 and 0.267 ± 0.021 for bacteria pretreated with egg yolk from immunized hens and unimmunized hens, respectively. Microscopic analysis showed that egg yolk from either immunized or unimmunized hens reduced bacterial adherence from 17 ± 2.7 bacteria per epithelial cell to less than 4 bacteria per epithelial cell. These results show that hen egg yolk significantly inhibits adherence ofS. typhimuriumto intestinal epithelial cells in vitro. Boosting of specific antibody levels does not enhance this antiadhesive effect, suggesting that egg yolk contains novel antiadhesive factors.
Textural and Ultrastructural Changes in Carrot Tissue as Affected by Blanching and Freezing
Authors: Roy S.S. , Taylor T.A. , Kramer H.L.
Published: August 2010

ABSTRACT: The impact of blanching and freezing conditions on firmness retention and ultrastructural changes in the cell wall and middle lamella of carrot tissues were studied. Freezing caused extensive degradation of cell wall pectins as evident from the rapid loss in tissue firmness. High‐temperature short‐time blanching (100°C, 0.58 min.; 90°C, 2.12 min.) retained firmer texture than low temperature long time blanching (80°C, 11.64 min.; 70°C, 71.1 min.). Freezing at rapid rates of ‐4.5°C/min and ‐2.4°C/min showed less softening than slow rates of ‐0.19°C/min and ‐0.05°C/min. Softening was further enhanced in blanched‐frozen carrots. Severe structural damage due to growing ice crystals and substantial loss of pectic material were seen at slower freezing rates.
Air Inclusion Into a Model Cake Batter Using a Pressure Whisk: Development of Gas Hold‐up and Bubble Size Distribution
Authors: Massey A.H. , Khare A.S. , Niranjan K.
Published: August 2010

ABSTRACT: This paper investigates the development of gas hold‐up (that is, gas volume fraction) and bubble size distribution in a model cake batter, which is aerated in a pressure whisk. With increasing aeration time, the hold‐up was found to pass through a maximum before approaching a uniform steady state value. A mathematical model that describes this profile has been developed. Bubble size distribution was found to be adequately described by a log normal distribution function with mean size varying between 20 and 50 μm. Higher pressures were found to increase hold‐up and mean bubble size, whereas higher whisk speeds reduced the time required to achieve a given hold‐up and the final mean bubble size.
Cryotolerance of Escherichia coli 0157:H7 in Laboratory Media and Food
Authors: Grzadkowska D. , Griffiths M.W.
Published: August 2010

ABSTRACT: The present study compared the cryotolerance of E. coli 0157:H7 strains with nonpathogenic strains of E. coli. Cold shocked (exposed to 10°C for 6 h) and non‐cold shocked (held at 20°C) cultures were frozen at ‐18°C for up to 240 h in brain heart infusion broth, apple juice, frozen yogurt, and ground beef. The E. coli 0157:H7 strains showed the greatest cold shock effect and cryotolerance. The cold shocked E. coli 0157:H7 strains showed a 25 to 35% increase in their ability to survive frozen storage for 24 h at ‐18°C compared to non‐cold shocked cells. The corresponding value for non‐O157 strains was only about 5%. The food matrix changed the cold shock response in all investigated strains. The largest cold shock effect was observed with broth cultures. Cryotolerance of E. coli was not observed in frozen yogurt and ground beef. The effect of prior cold shock was most pronounced in E. coli 0157:H7 strains after 24 h of freezing.
Concentration of Selected Vitamins in Infant Milks Available in Spain
Authors: Albalau‐Hurtado S. , Veciana‐Nogués M.T. , Vidal‐Carou M.C. , Font A. Mariné
Published: August 2010

ABSTRACT: Vitamins A, E, and those of the B complex were determined in 59 standard and 11 specialized infant milks from the Spanish market. Water‐soluble vitamin levels were lower than those declared by manufacturers in 50% of the standard infant milk products. Vitamin A ranged from 58.8 μg/100mL to 170.9 μ/100mL and vitamin E from 0.8 mg/100mL to 3.3 mg/100ml. Most of the samples had a higher vitamin A content than that stated by the manufacturer, and 13% and 42% of them exceeded the Spanish legislation and the ESPGAN recommendation levels respectively. Vitamin E levels were between 2 and 10 times higher than the minimum established by these organizations and in general were over the declared level.
Partial Substitution of Sugars by the Low‐Calorie Sweetener Sucralose in Peach Compote
Authors: Mendoncla C.R. , Zambiazi R. , Granada G.G.
Published: August 2010

ABSTRACT: This work aimed to elaborate light peach compotes by partial substitution of the sugar with low‐calorie sweeteners. Four formulations of fruit compote were elaborated and analyzed for their physical, chemical, and sensory characteristics and total caloric value, just after the manufacturing process and after 30, 60, and 90 d of storage. Consumer preference for the elaborated products was also verified. During the storage period, the peach compotes showed some significative variation of the physical and chemical aspects; however, just the reducer sugars content showed an expressive alteration. Caloric reduction was between 27.49% and 28.00%. According to the sensory attributes, significant differences were found among the 4 formulations, especially in relation to the attributes of flavor and acidity. The control and the formulations with sucralose and acesulfame‐K showed significant alteration to the sensory attributes of color and shine; additionally, the control formulation showed a significant alteration in relation to the flavor attribute. In the preference assay, the formulations showed the same preference.
Influence of Storage Atmosphere and Temperature on Quality Evolution of Cut Belgian Endives
Authors: Van de Velde M.D. , Hendrickx M.E.
Published: August 2010

ABSTRACT: An optimal combination of O2, CO2, and N2 for storage of cut Belgian Endive was defined, investigating visual quality aspects. In the experimental design, principles of mixture theory were used. The acceptability of cut endives stored under different gas combinations, selected in the range where both CO2 and O2 were varied between 2% and 18%, was evaluated by a consumer panel at different time intervals during storage. The response was modeled with a second‐degree polynomial, the response surface pointed in the direction of a gas mixture 10% CO2, 10% O2, and 80% N2 for maximum acceptability or best quality during storage. Repeated experiments, including different varieties from 2 different growers, confirmed the optimal gas concentration, (10% CO2, 10% O2, and 80% N2). In a second step, the effect of temperature on quality degradation of cut endives stored under optimal atmosphere conditions, was quantified using the Arrhenius equation. An activation energy of 16.3 kcal/mol was obtained.
Krzywicki Revisited: Equations for Spectrophotometric Determination of Myoglobin Redox Forms in Aqueous Meat Extracts
Authors: Tang J. , Faustman C. , Hoagland T.A.
Published: August 2010

ABSTRACT: Krzywicki's equations have been widely used for estimating the relative proportions of myoglobin (Mb) redox forms in aqueous solution. However, these equations have generated negative values for some redox forms, and total Mb estimates obtained by summation of the individual redox forms have deviated from unity. The inappropriate selection of wavelengths (545, 565, and 572 nm) used to generate these equations appears to have been responsible for these problems. Therefore, Krzywicki's equations were modified by using wavelength maxima at 503, 557, and 582 nm, representative for metmyoglobin, deoxymyoglobin, and oxymyoglobin, respectively. Millimolar extinction coefficients at these wavelengths were calculated, and a set of modified equations was established for determining the relative proportions of Mb redox forms in aqueous solution. The new equations demonstrated improved performance in decreasing the occurrence and magnitude of negative values and in estimating total Mb, when compared with Krzywicki' original equations.
Numerical Analysis of Heat Transfer during Surface Pasteurization of Hot Dogs with Vacuum‐Steam‐Vacuum Technology
Authors: Huang L.
Published: August 2010

ABSTRACT: The objective of this study was to validate the fundamental heat‐transfer mechanism governing the process of vacuum‐steam‐vacuum surface pasteurization of hot dogs. It was hypothesized that the steam could not directly flow into the pores below the surface of hot dogs, and the heat was transferred into these areas by conduction. A numerical analysis program was first developed to estimate the heat‐transfer coefficient between steam and hot dogs and was then used to simulate the temperature distribution at different locations below the surface. The hypothesis and computer simulation model were successfully validated using hot dogs surface‐inoculated with Listeria innocua. Results showed that the heat from saturated steam must be conducted into the interior to kill L. innocua harboring in the pores and irregularities below the surface of hot dogs. Results of computer simulation and biological validation also suggested that heating must be maintained at 138 °C for at least 25 s to achieve a complete elimination (> 8 log colony‐forming units per gram) of L. innocua from hot dogs.
Centrifugation and Foam Fractionation Effect on Mucilage Recovery from Dioscorea (Yam) Tuber
Authors: Fu Y.‐C. , Chen S. , Lai Y.‐J.
Published: August 2010

ABSTRACT: The yam (Dioscorea spp., Dioscoreaceae) is an important pharmaceutical plant that can be widely applied in the drug industry. The yam tuber is rich in starch and mucilage however, it is difficult to separate the starch from the tuber because of the viscous soluble carbohydrates‐protein (glycoprotein) present in the yam. These surface‐active complexes produce an extensive amount of foam. Foam fractionation is recognized as a suitable technique for recovering soluble, surface‐active substances from a solution using preferential adsorption at the gas‐liquid interface. The objective of this research is to compare foam fractionation and centrifugation for recovering the mucilage from yam tuber. The soluble carbohydrates and protein present in the mucilage are analyzed. The results showed that centrifugation may break down the soluble carbohydrates and protein complex, resulting in further soluble carbohydrates and protein separation in different parts of the starch paste and mucilage. With 2 consecutive centrifugations (7300 ×g), the total amounts of soluble carbohydrates and protein recovered from the Keelung yam (D. pseudojaponica Y.) tuber were 4.8% and 33.8%, respectively. It was found that excellent soluble carbohydrates (98.8%) and protein (74.1%) yield can be recovered in the Keelung yam using foam fractionation. Foam fractionation provides an alternative method for recovering viscous mucilage from yam. This is especially suitable for starch‐rich samples from the tuber.
Sensory Texture and Mechanical Properties of Stranded and Particulate Whey Protein Emulsion Gels
Authors: Gwartney E.A. , Larick D.K. , Foegeding E.A.
Published: August 2010

ABSTRACT: The influence of gel structure type and amount of lipid on texture of whey protein isolate (WPI) gels was evaluated by descriptive sensory analysis and determination of fracture and water‐holding properties. A series of 16 gels of varying structure (particulate or stranded) and lipid composition (0% to 20%) were developed at a constant protein concentration (12% w/v). Stranded gels had higher values for fracture strain, strain hardening, and held‐water. Particulate and stranded gels were similar in fracture stress. Eighteen sensory texture attributes were used to evaluate gels throughout the mastication process that was separated by the following phases: prefracture, 1st bite, chew‐down, and preswallowing. The 1st bite property of firmness and preswallowing properties of number of chews and time to swallow were the only sensory properties associated with lipid content. Fracture stress was correlated with these properties. The remaining 15 texture terms were primarily determined by gel structure type. It appears that gel structure type determines the primary texture properties of WPI emulsion gels. An increase in lipid content increases gel firmness and amount of chews required; however, it did not change the primary texture sensation.
How Diet and Health Labels Influence Taste and Satiation
Authors: Wansink B. , van Ittersum K. , Painter J.E.
Published: August 2010

ABSTRACT: Research on how diet and health labels (including advertising) influence taste or satiation shows mixed findings that are study‐specific and difficult to generalize. We offer a potential explanation to these inconsistencies. Results from a controlled cafeteria study suggest that health and diet labels might improve the perceived taste of less healthy, hedonic foods (such as desserts and possibly snack foods) without influencing the taste of more healthy utilitarian foods (such as entrées or possibly yogurt and soy foods). These findings have immediate implications for reinterpreting past research findings that may have gone unnoticed because they appeared inconsistent with conventional thinking.
Impact of Label Information on Consumer Assessment of Soy‐enhanced Tomato Juice
Authors: Goerlitz C.D. , Delwiche J.F.
Published: August 2010

ABSTRACT: The impact of label information on the liking and closeness to ideal of tomato juice beverages was examined by having 100 judges assess 3 tomato juice beverages (Campbell's tomato juice, V8 juice, and an experimental tomato juice enhanced with soy) either with or without labeling information. Judges rated overall liking of each product and then rated appropriateness of various attributes (saltiness, tomato flavor, thickness, texture, red color, orange color, and brown color) on 5‐point just‐right scales. Only half of the judges were presented with product‐related label information during evaluation. Overall liking scores were analyzed using repeated‐measures ANOVA, whereas different attribute ratings were analyzed using Thurstonian Ideal Point modeling and Chi‐square. Product‐associated label information did not significantly alter overall liking ratings (P > 0.05), although a significant difference in liking was found between products (P < 0.05). Similarly, the label information did not impact comparison of product attribute levels to ideal attribute levels. Both V8 and Campbell's were significantly different from the ideal for 3 of the attributes (P < 0.05). For the soy‐enhanced tomato juice, all 7 attributes were significantly different from the ideal (P < 0.05). In this instance, labeling information had no notable impact on assessments.
Photostability of Sodium Iron Ethylenediaminetetraacetic Acid (NaFeEDTA) in Stored Fish Sauce and Soy Sauce
Authors: Fidler M.C. , Krzystek A. , Walczyk T. , Hurrell R.F.
Published: August 2010

ABSTRACT: Sodium iron ethylenediaminetetraacetic acid (NaFeEDTA) has been suggested as a fortification compound for fish sauce and soy sauce. Its susceptibility to photodegradation in aqueous solutions however is a potential disadvantage. We determined the photostability of NaFeEDTA in fish and soy sauce stored under well‐defined conditions. No degradation of NaFeEDTA was observed during storage of fortified soy sauce. Losses of up to 35% NaFeEDTA, however, occurred within 2 to 6 wk in fortified fish sauce stored in clear bottles exposed to direct sunlight. Losses were prevented by storage in amber bottles or by storing the clear bottles under indirect sunlight or in the dark.
Foaming and Interfacial Properties of Polymerized Whey Protein Isolate
Authors: Davis J.P. , Foegeding E.A.
Published: August 2010

ABSTRACT: Yield stresses (τ) of whipped foams prepared from various ratios of native whey protein isolate (WPI) and polymerized whey protein isolate (pWPI) were characterized by means of vane rheometry Yield stress displayed a parabolic response to increasing concentrations of pWPI, peaking at 50%. Foam air phase volume steadily decreased with increasing pWPI content, whereas equilibrium surface tension steadily increased. Dynamic surface tension measurements revealed that native WPI adsorbed much more rapidly than pWPI, presumably because of the latter's larger size. Interfacial dilatational elasticity (E') displayed a parabolic trend with increasing pWPI content, peaking at 50%. This suggested that pWPI coadsorbs with native WPI, bolstering E' of native WPI interfaces. However, too much pWPI caused a weakening of the network. A positive, curvilinear relationship between E' and τ was observed, consistent with a previous observation for WPI foams formed at various pH levels and salt concentrations, further suggesting a general link between these parameters.
Optimization of Cheddar Cheese Taste in Model Cheese Systems
Authors: Yang B. , Vickers Z.
Published: August 2010

ABSTRACT:To construct a Cheddar taste in media similar to Cheddar cheese, we developed dairy, nondairy, and mozzarella model systems. We trained a descriptive analysis panel to evaluate real and model cheeses for a variety of taste attributes and for Cheddar‐like taste. We added sodium chloride, lactic acid, citric acid, and monosodium glutamate to the model systems using mixture designs and used response surface methodology to determine optimum levels of these 3 components. Less sodium chloride and acids were needed to simulate the taste of mild Cheddar compared with aged Cheddar. None of the model cheeses closely mimicked the texture of real Cheddar. We approximated, but did not match, the taste of aged cheddar using our mozzarella base. Panelists generally rated the optimized tastes in the dairy model system as more Cheddar‐like than the optimized tastes in the nondairy model.
Education Making the Transition to Outcomes‐based Instruction
Authors: ARTEL RICHARD W. H
Published: August 2010

ABSTRACT: The new IFT Education Standards require that all IFT‐approved Food Science programs have an assessment plan for evaluating student learning. Learning outcomes must be written for each individual course as well as for the curriculum as a whole and assessment within each course and across the curriculum is recommended. This approach is significantly different from the traditional education approach used most commonly and requires a change in perspective on the meaning of teaching and learning without sacrificing the good things that come out of our current education system. For most programs, the first step in developing an assessment program is to identify a set of learning outcomes in the broadest sense. The assistance of an education expert to help write true learning outcomes should be solicited; as well, input from the industrial sector should be invited. Once learning outcomes have been developed for the curriculum as a whole, individual courses can be prepared to bring the most logical learning sequence together. Individual courses may follow traditional lines or courses may be reorganized in some other way to promote student learning within the resources of the program. As the curriculum is designed, thought should be given to how student learning develops across the curriculum. For example, developing team work skills may be coordinated at several points in the curriculum. In this way, students are exposed to the concepts, allowed to practice their skills, and then evaluated on their competence in a manner consistent with what they will be required to do upon graduation. Using the approach suggested here, a curriculum with coordinated instruction to promote and to assess student learning can be developed. The outcome of such an approach to instruction will be enhanced student learning and competency upon graduation.
Study of Acetylated Food Proteins by Raman Spectroscopy
Authors: HAO Y. Z , MA C. Y. , YUEN S. N. , PHILLIPS D. L.
Published: August 2010

ABSTRACT: Three food proteins, soy protein isolates, spray‐dried egg white, and whey protein isolates, were acetylated to varying levels, and the extent of modification was determined by wet chemistry methods. Raman spectra of the modified proteins were obtained. A new C=O stretching vibration was observed at 1737cm‐1 and was attributed to ester carbonyl groups appended to the proteins during acetylation. Calibration curves were obtained by plotting the intensity ratio of this Raman band to the 1003cm‐1 phenylalanine stretching band against the extent of substituted hydroxyl groups. Linear fits were obtained with correlation coefficient r> 0.9979. The Raman spectral data were also analyzed to study the effect of acetylation on the conformation of the 3 proteins. Marked conformational changes were observed in the modified proteins.
Development of an Orange‐flavored Barley β‐Glucan Beverage with Added Whey Protein Isolate
Authors: Temelli F. , Bansema C. , Stobbe K.
Published: August 2010

ABSTRACT:Whey protein isolate (WPI) frommilkand (l→3), (l→4)‐β‐D‐glucan (β‐glucan), a soluble fiber component found in barley, were used together to formulate a functional beverage product. Formulations tested included 0.5% (w/w) β‐glucan with 0%, 0.5%, 1.0%, and 1.5% (w/w) WPI. Trained and consumer panels evaluated beverage quality and acceptability. Shelf stability of products was assessed. Trained panelists found beverages to be similar in sweetness intensity (P> 0.05). Sourness and orange‐flavor intensity decreased (P0.05) as WPI concentration increased, whereas beverage cloudiness and viscosity increased (P0.05). The consumer panel found no difference (P > 0.05) in the degree of liking for all the attributes studied. Beverages were found to be stable throughout the 8‐wk storage period. Barley β‐glucan shows great potential as a functional beverage ingredient.
Rapid Heating Effects on Gelation of Muscle Proteins
Authors: Riemann A.E. , Lanier T.C. , Swartzel K.R.
Published: August 2010

ABSTRACT: The hypothesis was tested that total thermal input (combined time and temperature), rather than merely heating rate, is the determining factor in heat‐induced gel formation by muscle proteins. For comminuted pastes of pollock surimi and turkey breast, rapid heating plus a brief holding time at the endpoint temperature produced similar textural properties to gels, which were heated by a slower cook schedule and cooled immediately. These results suggest that the equivalent point method, a tool used to compare and communicate equivalent heat treatments for effecting bacterial reduction and/or enzyme inactivation, can be used to identify other heat processes having similar effects on gelation.
Dynamic Head Space Analyses of Orange Juice Flavor Compounds and Their Absorption into Packaging Materials
Authors: Sheung K.S.M. , Min S. , Sastry S.K.
Published: August 2010

ABSTRACT: A simple, rapid, sensitive, and reproducible dynamic headspace gas chromatography (DH‐GC) was developed to study the absorption of d‐limonene, α‐pinene, ethyl butyrate, and octanal into laminated polymeric packaging materials containing low‐density polyethylene, polyethylene terephthalate, polyvinylidene chloride, and ethyl‐ene‐vinyl alcohol copolymers. The linear regression lines showed that the flavor compound peak areas were directly proportional to the concentrations of the standard flavor compounds with R2≥ 0.97. The coefficients of variation for the DH‐GC analyses were less than 4%. A test cell was designed to study orange juice flavor absorption into the packaging materials for 28 d at 25 °C. Ethyl butyrate or octanal absorption was not different among the 4 packaging materials (P > 0.05). Addition of a polyethylene terephthalate and a ethylene‐vinyl alcohol copolymer layer to the packaging materials reduced the d‐limonene and α‐pinene absorption by 20% and 50%, respectively.
Oxidative Stability of Soybean and Sesame Oil Mixture during Frying of Flour Dough
Authors: Chung J. , Lee J. , Choe E.
Published: August 2010

ABSTRACT: Effects of roasted sesame seed oil on the oxidative stability of soybean oil during frying of flour dough at 160 °C were studied by determining fatty acid composition and conjugated dienoic acid (CDA), p‐anisidine (PA), and free fatty acid (FFA) values. Concentration of sesame oil in frying oil was 0%, 10%, 20%, or 30% (v/v). Tocopherols and lignan compounds in the frying oil were also determined by high‐performance liquid chromatography. As the number of fryings performed by the oil increased, linolenic acid content in frying oil decreased, and the decreasing rate was lower in frying oil containing sesame oil than in the oil containing no sesame oil. CDA and FFA values of frying oil increased during frying and their relative values to the initial value were lower in frying oil containing sesame oil than in the oil containing no sesame oil. This indicates that the addition of sesame oil improved thermooxidative stability of frying oil, possibly due to the presence of lignan compounds in sesame oil. Tocopherols and lignan compounds in frying oil decreased during frying. As the amount of sesame oil in frying oil increased, degradation of tocopherols increased and lignan compounds degradation decreased. Tocopherols were suggested to protect lignan compounds in sesame oil from decomposition during frying.
Soils for Sustaining Global Food Production
Authors: BLUM WINFRIED E.H. , SWARAN HARIE
Published: August 2010

ABSTRACT: Soil is commonly described as the mantle or the skin covering the landmass of planet Earth. Soils perform 6 main functions (biomass production, water quality maintenance, biological habitat, physical infrastructure support, raw materials for human use, and maintaining cultural heritage) and a soil is evaluated by its ability to perform one or more of these functions. The ability of the land to feed and clothe people and to maintain ecological functions is being impeded by demographics. The global land area that is generally free of constraints for most agricultural uses is about 12.6%. Agricultural land, however, is unequally spread around the globe with a larger portion in the temperate countries of the world. In addition to poorer land quality in tropical regions, land degradation is also well entrenched, thus aggravating food security. There are 11.9 million km2 of such lands and about 1.4 billion people are involved and most of these areas are in the developing countries. Countries of the developing parts of the world have to make a conscious decision to better manage their land resources. The paradigm shift that poorer countries need to make to sustain food production is to implement holistic and sustainable land management programs by adopting technologies that have already been validated in other parts of the world.
Agrosecurity: The Role of the Agricultural Experiment Stations
Authors: NIPP TERRY
Published: August 2010

ABSTRACT: In order to protect the nation's agriculture and food processing systems from the new threat of bioterror‐ism, agricultural and food technology research must be effectively harnessed and applied. The U.S. conducts the majority of its agricultural research through state‐based Agricultural Experiment Stations. To respond to the new challenges of biosecurity, and to facilitate communication between the federal research system and the state‐based agricultural research system, the Directors of the State Agricultural Experiment Stations (SAES) facilitated the creation of a National Institute for Agricultural Security (NIAS). The mission of NIAS is to help address national homeland security and biosecurity issues that affect the nation's farms and ranches, food production and distribution system, and rural communities by harnessing, coordinating, and targeting agricultural research and food science technology projects. NIAS was created to provide a “front door” and “one‐stop shopping” for federal agencies and the public. NIAS is currently developing projects to improve site security at SAES field stations and laboratories. The Institute is facilitating the development of prototype‐secured information technology networks. NIAS is serving as a liaison to federal agency offices to help identify high priority agricultural and food science research needs. The Institute is also exploring the possibility of collaborating in the development of regional pathogen outbreak simulations with the regional university coordinators of the Dept. of Agriculture's National Plant Diagnostics Network (NPDN). NIAS is collaborating with the Institute for Countermeasures Against Bioterrorism to host an international workshop on the managing of events when harmful pathogens are introduced into the food supply. And, NIAS is exploring the potential role of university Cooperative Extension Service as part of the “first responder network,” as “first detectors,” and as facilitators for helping rural community leaders plan to address homeland security concerns.
Functional Properties of Protein Isolate from Cowpea (Vigna unguiculata L. Walp.)
Authors: HORAX R. , HETTIARACHCHY N. S. , CHEN P. , JALALUDDIN M.
Published: August 2010

ABSTRACT: Functional properties of protein isolates prepared from 3 cowpea varieties and 2 soybean varieties in each of 2 y were determined. Both cowpea protein isolate (CPI) and soy protein isolate (SPI) showed a u‐shaped curve for solubility with the minimum solubility occurring at pH 4.5. The CPI had lower emulsifying activity than SPI but was similar in stability. Foaming capacity and foaming stability ranged from 58.6 to 60.2 mL and 63.7 to 64.4 min for CPI and from 31.9 to 33.0 mL and 43.4 to 45.0 min for SPI, respectively. Gels were formed at 70 °C for 40 min and 30 min for CPI (12%) and SPI (10%), respectively. The CPI needs modification to enhance functional properties for potential application in food products.
Effect of 1‐Methylcyclopropene Treatment and Edible Coatings on the Quality of Minimally Processed Lettuce
Authors: TAY S. L. , PERERA C. O.
Published: August 2010

ABSTRACT: The effects of 1‐methylcyclopropene (1‐MCP) and alginate‐based edible coatings on the rate of respiration, C2H4 production, color, texture, and total ascorbic‐acid level of minimally processed and stored Baby Butterhead lettuce were determined. Samples were stored at 2 °C and 6 °C for 12 d. It was observed that the 1‐MCP‐treated lettuce had the lowest respiration and ethylene production rates. Russet spotting on the midribs of the leaves in 1‐MCP‐treated lettuce was the most retarded, and the total ascorbic acid level was the highest. Alginate treatment of lettuce had the most pronounced effect on crispness. Overall, the 1‐MCP‐treated lettuce had the best quality, followed by the alginate‐coated and the control lettuce.
Numerical Simulation and Experimental Investigation of Conjugate Heat Transfer between a Turbulent Hot Air Jet Impinging on a Cookie‐shaped Object
Authors: NITIN N. , KARWE M. V.
Published: August 2010

ABSTRACT: Numerical simulation of the flow field and conjugate heat transfer for a turbulent jet impinging on the surface of a model cookie were carried out at different nozzle‐to‐plate spacings. Numerical predictions were compared with the experimental results on average and the local heat‐transfer coefficient. Results indicated good agreement between the numerical and experimental results over the range of jet velocities, that is, 10 to 40 m/s, which corresponds to Reynold's number range of 7500 to 32000 based on the jet orifice diameter. Numerical simulation also confirmed that the surface heat‐transfer coefficient was independent of the thermo‐physical properties of the cookie. The local heat‐transfer coefficient on the top surface of the cookie was highest at the center of the impinging jet.
Effect of pH on Thermal and/or Pressure Inactivation of Victoria Grape (Vitis vinifera sativa) Polyphenol Oxidase: A Kinetic Study
Authors: Rapeanu Gabriela , Loey Van , Smout Chantal , Hendrickx Marc
Published: August 2010

ABSTRACT: Thermal and/or high pressure inactivation of polyphenol oxidase (PPO), isolated from grapes (var. Victoria, South Africa) was studied as a function of pH. Temperature as well as pressure stability increased with increasing pH from 3 to 6. Both thermal (pH range, 3 to 6) and thermal‐high pressure inactivation (pH = 3) of the enzyme followed 1st order kinetics. The zt value and activation energy, both reflecting the temperature dependency of the inactivation rate constant, respectively, slightly decreased and increased with increasing pH from 3 to 6. The thermal‐high pressure inactivation of Victoria grape PPO was kinetically investigated in a model system at pH 3.0. A3rd‐degree polynomial model was successfully applied to describe the temperature/pressure dependence of the inactivation rate constants. Pressure and temperature were found to act synergistically, except in the high temperature (≥45°C)‐low pressure (≤300 MPa) region where an antagonistic effect was observed.
Fixed and Incremental Levels of Microwave Power Application on Drying Grapes under Vacuum
Authors: Clary Carter D. , Wang Shaojin , Petrucci Vincent E.
Published: August 2010

ABSTRACT: Microwave vacuum drying has been investigated as promising potential for high‐quality dried fruits. In this study, a batch microwave vacuum dryer was used to understand the effect of levels of microwave power on the drying characteristics and moisture content of grapes. Thompson seedless grapes were treated 1st for 30, 60, and 90 min at fixed levels of 500, 750,1000,1250, and 1500 W at a reduced pressure of 2.7 kPa and then treated by 3 staged microwave power levels: a higher level of power during the initial stages of dehydration and 2 subsequently lower levels of power applied as the moisture content decreased. A typical temperature profile was found during the drying process, linearly increasing at the start of drying, followed by a nearly constant value during the drying period while water was evaporating. The total specific energy estimated by the energy balance model was 0.97 to 1.01 W‐h/g of fresh grapes and agreed well with the experimental specific energy of 0.85 to 0.90 W‐h/g for the fixed power tests. The multiple regression results showed that the specific energy was the most influential parameter on the final moisture content of grapes both in fixed and incremental power levels. Further research is needed to further improve the process with high efficiency and good product quality using product temperature as a control measure. Keywords: microwave vacuum dehydration, specific energy, fruits, grapes
Characteristics of Clear Noodles Prepared from Edible Canna Starches
Authors: Chansri Ruethaipak , Puttanlek Chureerat , Rungsadthogy Vilai , Uttapap Dudsadee
Published: August 2010

ABSTRACT: Clear noodles were prepared from starches of 3 edible canna cultivars namely; Thai‐purple, Thaigreen, and Japanese‐green. The effects of amount of gelatinized starch, moisture content of dough, and holding temperature after cooking on noodle appearance were investigated. Ten percent gelatinized starch, 55% moisture content, and holding temperature at 4°C for 24 h gave clear noodles with appearance, cooking loss, and rehydration ratio comparable to commercial mung bean noodles. However, the canna noodles were of inferior tensile strength. Moisture content of the canna noodles was 15.24% to 15.46%. Their chemical compositions on dry weight basis were as follows: 89.41% to 91.63% starch, 0.21% to 0.33% protein, > 0.01% lipid, 0.16% to 0.20% ash. Measured diameters of noodles were in the range of 0.73 to 0.88 mm. The cooking losses were 0.93% to 0.55% dry weight, whereas tensile stresses were 17.44 to 22.77 g/mm2. The energy values derived from 100 g of canna noodles were 358.48 to 367.84 kcal. Sensory evaluation by descriptive test revealed that there were no significant differences (P ≤ 0.05) in the general acceptability between the canna noodles and the commercial mung bean noodles. By paired‐comparison test, however, the commercial mung bean noodle A was more favorable.
Human Milk Banking: Influence of Different Pasteurization Temperatures on Levels of Protein Sulfur Amino Acids and Some Free Amino Acids
Authors: Carratù Brunella , Ambruzzi Amalia Maria , Fedele Elena , Sanzini Elisabetta
Published: August 2010

Human milk is frequently heat‐treated in hospitals, particularly milk that is banked, to destroy contaminating bacteria and viruses, but this treatment simultaneously reduces the content of some vitamins, enzymes, and immunological and nutritional factors. This study was performed to find the optimal conditions for heat treatment. The effects of 2 pasteurization temperatures on levels of protein sulfur amino acids (methionine, cystine) and some free amino acids (taurine, glutamine, glutamic acid) in light of the oxidative instability that occurs especially during thermal treatment were examined. These substances in raw human milk and in milk treated at 56.5 °C and 62.5 °C for 30 min were compared. Samples of mature human milk from all feeds over 24 h were obtained from 13 healthy well‐nourished mothers of term infants. Each sample was divided into 3 parts: raw, treated at 56.5 °C for 30 min, treated at 62.5 °C for 30 min. The results showed that the availability of sulfur amino acids and free taurine is the same after heat treatment, whereas milk processing increased positively the levels of free glutamic acid and glutamine, but there is significance only for glutamine. The mean quantities of considered amino acids were similar in milk treated at the recommended pasteurization temperature (30 min at 62.5 °C) and at 56.5 ° for 30 min.
Functional and Nutritional Properties of Red Salmon (Oncorhynchus nerka) Enzymatic Hydrolysates
Authors: Sathivel Subramaniam , Smiley Scott , Prinyawiwatkul Witoon , Bechtel Peter J.
Published: August 2010

The effects of different proteolytic enzymes and different reaction durations (25, 50, 75 min) on functional and nutritional properties of red (sockeye) salmon head hydrolysates were evaluated. Degree of hydrolysis values for the 75‐min digestion ranged from 6.4% to 16.7%. Oil yield (4.9% to 10.6 %) from red salmon heads was affected by the enzyme used. Protein hydrolysate powders were yellowish and contained 62.3% to 64.8% protein with high levels of essential amino acids. Increased degree of hydrolysis values were weakly correlated with increased hydrolysate solubility. Maximum emulsion stability and fat adsorption were observed for the dried hydrolysate generated in the 25‐min reaction time. Water adsorption of hydrolysate powders ranged from 1.0 mL to 3.3 mL water/g dried hydrolysate.
Microencapsulating Properties of Trehalose and of its Blends with Sucrose and Lactose
Authors: Cerdeira Marina , Martini Silvana , Herrera Maria L.
Published: August 2010

A low melting fraction of milk fat (LMF), with a dropping point (MDP) of 16.7 °C, was encapsulated by freeze‐drying emulsions formulated with trehalose or its blends with 30 wt% lactose or sucrose as hydrophilic phase, and with a mixed of 50 wt% of the palmitic sucrose esters (SE) β‐170 and β‐1670 as emulsifiers. Trehalose or trehalose/sucrose matrices were very efficient to encapsulate LMF (retention values were 82.8%± 3.2% and 90.5%± 3.7%, dry basis, respectively), whereas trehalose/lactose showed a significant decline in initial retention (42.5%± 2.5%, dry basis). The role of emulsion stability, water content, physical state of the matrix, and particle size distribution on LMF loss was investigated by following retention of LMF with time for the powders stored at water activities (aw) of 0.11, 0.33, 0.44, 0.54, and 0.76. Trehalose emulsion was the most stable. However, encapsulation efficiency was higher for the trehalose/sucrose blend. Despite the high initial degree of crystallization, retention with time for the trehalose matrix was very high at all aw. The trehalose/lactose blend had a low efficiency to encapsulate LMF, especially at aw of 0.54 and 0.76. Retention was determined by the counteracting effects of all these factors and was more closely related to structural changes of the encapsulating matrix than to the physical state (amorphous or crystalline) of it.
Fermentation Capabilities of Bifidobacteria Using Nondigestible Oligosaccharides, and Their Viability as Probiotics in Commercial Powder Infant Formula
Authors: Pérez‐Conesa Darío , López Ginés , Rosau Gaspar
Published: August 2010

The species Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum biotype infantis (Spanish type culture collection), and Bifidobacterium longum (Morinaga nutritional foods) were evaluated in vitro in the presence of 4 commercial nondigestible oligosaccharides (NDO) (short‐chain fructooligosaccharides [SCFOS] [degree of polymerization, DP: 2–3], inulin [DP: 10–0], oligofructose [DP: 2–0] and 4′‐galactosyllactose [4′‐GOS] [DP: 3–]). Each species was incubated anaerobically in tryptone phytone yeast (TPY) broth for 7 d with NDO. Every 24 h, bifidobacteria growth was evaluated by means of broth turbidity as optical density at 600 nm. Moreover, another sample was collected for pH culture measurement. Results showed that inulin was the substrate with the least effect on the stimulation of bifidobacteria growth and pH decrease. On the last day of incubation, the substrate 4′‐GOS stimulated bacterial growth more strongly and produced a larger decrease in culture broth pH than the other substrates. On the other hand, B. bifidum and B. longum showed a greater growth with 4′‐GOS. In a 2nd study, these 2 bifidobacteria species were added to a powder follow‐on probiotic infant formula. The viability of the bifidobacteria during the formula's period of consumption was evaluated in 2 studies of 6 and 14 d. Both corresponded to the minimum and maximum time of consumption of the formula according to the manufacturer's directions. It was found that, although in both studies bifidobacteria counts decreased significantly (P < 0.05) with time, they were always above the recommended addition level (106 colony‐forming units [CFU]/g) at the time of sale for dairy products by the Intl. Standard of Fédération Internationale de Laiterie/International Dairy Federation (FIL/IDF). Moreover, because the pH of the reconstituted formula was always close to neutrality (from 6.74 to 7.06), the number of bacteria did not drop below the recommended level.
Comparison of Shelf Life of Eggs Coated with Chitosans Prepared under Various Deproteinization and Demineralization Times
Authors: No Hong Kyoon , Prinyawiwatkul Witoon , Meyers Samuel P.
Published: August 2010

Internal quality of eggs coated with chitosans prepared under various deproteinization (DP at 0, 5, 15 min) and demineralization (DM at 0, 10, 20, 30 min) times was evaluated. Chitosans prepared under DP 0 min/DM 30 min, DP 5 min/DM 30 min, and/or DP 15 min/DM 20 min conditions can be effectively used as an egg‐coating material in preserving the internal quality of eggs compared with chitosan prepared under the DP 15 min/DM 30 min condition. The Haugh unit and yolk index values suggested that the chitosan‐coated eggs can be preserved for at least 2 wk longer than the control noncoated eggs during 5 wk of storage at 25°C.
Potato Chip Quality and Frying Oil Stability of High Oleic Acid Soybean Oil
Authors: Warner Kathleen , Gupta Monoj
Published: August 2010

High oleic soybean (HOSBO) and low linolenic acid soybean (LLSBO) oils were evaluated individually and in a 1:1 blend along with cottonseed oil (CSO) to determine frying oil stabilities and the flavor quality and stability of potato chips. Potato chips were fried in the oils for a total of 25 h. Potato chips and oils were sampled periodically for sensory data, gas chromatographic volatile compounds, free fatty acids, and total polar compounds. Total polar compounds levels decreased with increasing amounts of oleic acid. The LLSBO had the highest overall increase (17.3%) in total polar compounds from 0 to 25 h of frying. Flavor evaluations of fresh and aged (0, 1, 3, 5, and 7 wk at 25 °C) potato chips showed differences between potato chips fried in different oil types. Potato chips fried in either LLSBO or in the 1:1 blend had significantly higher intensities of deep fried flavor than the chips fried in HOSBO. Potato chips fried in HOSBO, which had 2% linolenic acid and 1.3% linoleic acid, had significantly higher fishy flavor intensity than chips fried in the other oils. The presence of linoleic acid at a level lower than the amount of linolenic acid probably allowed for the fishy flavors from the degradation of linolenic acid in HOSBO to become more apparent than if the linoleic acid level was higher than linolenic acid. Hexanal was significantly higher in potato chips fried in LLSBO than in the chips fried in the other oils, indicating low oxidative stability during storage. Blending HOSBO with LLSBO in a 1:1 ratio not only improved flavor quality of chips compared with those fried in HOSBO, but also improved oil fry life and oxidative stability of chips compared with LLSBO.