Home About us Contact
|
Home About us Contact | ||
|
|
||
Conditions
Kinds of Conditions Terms modified by Conditions Selected AbstractsWHO'S AFRAID OF THE MARSHALL-LERNER CONDITION?ECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 4 2005Gordon D. Menzies The Marshall-Lerner condition,that the sum of the elasticities of import and export demand exceeds unity,has been put forward as a condition that is required for a depreciation to make the trade balance more positive. Based on recently estimated trade equations, the more appropriate condition for Australia is that the sum of the import elasticity of demand and the elasticity of the export price with respect to the exchange rate exceeds unity. I call this the Small Economy Marshall,Lerner (SEML) condition. In recent history, this condition was fulfilled in 1999,2001, when the (unstable) relationship between the terms of trade and the exchange rate broke down. [source] THE ECONOMICS OF THE UNCOVERED INTEREST PARITY CONDITION FOR EMERGING MARKETSJOURNAL OF ECONOMIC SURVEYS, Issue 1 2009C. Emre Alper Abstract Financial account liberalizations since the second half of the 1980s paved the way for the burgeoning literature that investigates foreign exchange market efficiency in emerging markets (EMs) via testing for the uncovered interest parity (UIP) condition. This paper is the first to provide a broad and critical survey on this recent literature. Specifically, we attempt to answer the following questions. First, are the EMs different from the developed economies in the context of the UIP condition? Second, to what extent can these differences contribute to the debate on the UIP literature? Third, what are the empirical challenges specific to the EMs in testing for the UIP condition? [source] HYGIENE PERCEPTION: CONDITION OF HOTEL KITCHEN STAFFS IN ANKARA, TURKEYJOURNAL OF FOOD SAFETY, Issue 2 2010NEVIN SANLIER ABSTRACT The study, which analyzed knowledge levels of the staff who work in food and beverage departments of hotels in Turkey about food safety, was carried out in December 2007,March 2008. Researchers applied face to face survey to 522 employees of seven hotels. The difference has been found meaningful statistically between kitchen and kitchenware hygiene, employee hygiene, food hygiene and general hygiene knowledge points and their education status and occupations in the result of the study (P < 0.05). On the other hand, a meaningful relationship has not been found statistically between food safety knowledge levels of the staff and their age ranges (P > 0.05). First, it is required to pay attention to the determining of the training needs of employees working for the enterprise, and to make a point of applying necessary training and seminars concerning the staff in each degree by making a training program. It has been determined that training, occupation and experience of the staff are so important in order to provide food safety in enterprises. PRACTICAL APPLICATIONS Each year, millions of people worldwide suffer from foodborne diseases and illnesses. Therefore, food-related infection is an important health problem in many countries. This study analyzed the knowledge levels of employees who work in the food and beverage departments. It has been found that there is a need to develop a state policy regarding education to be given to consumers and employees about food safety knowledge and practices. Education should be repeated with specific intervals to ensure that learnt information is turned into attitudes and behaviors; and procedures and processes should be controlled regularly. [source] SMOOTHING WITH AN UNKNOWN INITIAL CONDITIONJOURNAL OF TIME SERIES ANALYSIS, Issue 2 2003Piet De Jong Abstract. The smoothing filter is appropriately modified for state space models with an unknown initial condition. Modifications are confined to an initial stretch of the data. An application illustrates procedures. [source] FRAMING THE HUMAN CONDITION: THE EXISTENTIAL DILEMMA IN IRIS MURDOCH'S THE BELL AND MURIEL SPARK'S ROBINSONTHE HEYTHROP JOURNAL, Issue 5 2007MICHAEL GIFFIN One of the features of modernist and postmodernist novels is the way they interrogate classical metaphysics, in the spirit of what Habermas calls post-metaphysical thinking, otherwise known as the post-Enlightenment critique of the Enlightenment. As a literary prism, post-metaphysical thinking is not anti-metaphysical: it conducts its interrogation and still accommodates both secular and religious frames. Iris Murdoch and Muriel Spark are often compared but they interrogate classical metaphysics from different perspectives and for different purposes. In the nineteen-fifties, Murdoch was an aspiring philosophical author who treated classical metaphysics as a canon of influential myth, while Spark was an aspiring theological author who had recently converted to Catholicism. Through a reading of The Bell and Robinson, both published in the same year, this article describes how the young Murdoch and Spark do what emerging literary authors of the nineteen-fifties were expected to do: frame the human condition and reflect on its existential dilemma. With their different perspectives they both write within the same paradigm, or theory of mind; against symbolic backgrounds, and among significant dialogues, they make use of similar tropes. But Murdoch and Spark arrive at opposite positions on the relationship between imagination and reality, between logos and mythos, and ultimately on the nature of freedom and contingency. [source] RATIONAL CAPACITY AS A CONDITION ON BLAMEANALYTIC PHILOSOPHY, Issue 2 2007Pamela Hieronymi First page of article [source] THE CONDITION OF MUSIC: WAGNERISM AND PRINTMAKING IN FRANCE AND BRITAINART HISTORY, Issue 3 2009RACHEL SLOAN Scholarship on the impact of Richard Wagner's music and aesthetic theories has traditionally concentrated on fin-de-siècle France. Aubrey Beardsley's Wagnerian prints have recently been the subject of several significant studies, but they have been examined in a British context with little reference to earlier or concurrent developments in France. This article serves as a case study of Anglo-French artistic exchange at the fin-de-siècle, examining some points of interaction between Beardsley and two key French Wagnerian artists, Henri Fantin-Latour and Odilon Redon, in order to throw more light on the complex mixture of political, social and aesthetic discourses that informed all three artists' interest in the intersection of music and the visual arts, as well as their Wagnerian pictorial languages. [source] STABILITY CONDITION OF DISTRIBUTED DELAY SYSTEMS BASED ON AN ANALYTIC SOLUTION TO LYAPUNOV FUNCTIONAL EQUATIONSASIAN JOURNAL OF CONTROL, Issue 1 2006Young Soo Suh ABSTRACT An analytic solution to Lyapunov functional equations for distributed delay systems is derived. The analytic solution is computed using a matrix exponential function, while conventional computation has been relied on numerical approximations. Based on the analytic solution, a necessary and sufficient stability condition for distributed delay systems with unknown but bounded constant delay is proposed. [source] TACIT COLLUSION IN AUCTIONS AND CONDITIONS FOR ITS FACILITATION AND PREVENTION: EQUILIBRIUM SELECTION IN LABORATORY EXPERIMENTAL MARKETSECONOMIC INQUIRY, Issue 3 2009JIN LI The paper studies bidder behavior in simultaneous, continuous, ascending price auctions. We design and implement a "collusion incubator" environment based on a type of public, symmetrically "folded" and "item-aligned" preferences. Tacit collusion develops quickly and reliably within the environment. Once tacit collusion developed, it proved remarkably robust to institutional changes that weakened it as an equilibrium of a game-theoretic model. The only successful remedy was a non-public change in the preference of participants that destroyed the symmetrically, "folded" and "item aligned" patterns of preferences, creating head-to-head competition between two agents reminiscent of the concept of a "maverick."(JEL L50, L94, D43) [source] HOST GROWTH CONDITIONS INFLUENCE EXPERIMENTAL EVOLUTION OF LIFE HISTORY AND VIRULENCE OF A PARASITE WITH VERTICAL AND HORIZONTAL TRANSMISSIONEVOLUTION, Issue 7 2010Hélène Magalon In parasites with mixed modes of transmission, ecological conditions may determine the relative importance of vertical and horizontal transmission for parasite fitness. This may lead to differential selection pressure on the efficiency of the two modes of transmission and on parasite virulence. In populations with high birth rates, increased opportunities for vertical transmission may select for higher vertical transmissibility and possibly lower virulence. We tested this idea in experimental populations of the protozoan Paramecium caudatum and its bacterial parasite Holospora undulata. Serial dilution produced constant host population growth and frequent vertical transmission. Consistent with predictions, evolved parasites from this "high-growth" treatment had higher fidelity of vertical transmission and lower virulence than parasites from host populations constantly kept near their carrying capacity ("low-growth treatment"). High-growth parasites also produced fewer, but more infectious horizontal transmission stages, suggesting the compensation of trade-offs between vertical and horizontal transmission components in this treatment. These results illustrate how environmentally driven changes in host demography can promote evolutionary divergence of parasite life history and transmission strategies. [source] THE CONDITIONS FOR SPECIATION THROUGH INTRASPECIFIC COMPETITIONEVOLUTION, Issue 11 2006Reinhard Bürger Abstract It has been shown theoretically that sympatric speciation can occur if intraspecific competition is strong enough to induce disruptive selection. However, the plausibility of the involved processes is under debate, and many questions on the conditions for speciation remain unresolved. For instance, is strong disruptive selection sufficient for speciation? Which roles do genetic architecture and initial composition of the population play? How strong must assortative mating be before a population can split in two? These are some of the issues we address here. We investigate a diploid multilocus model of a quantitative trait that is under frequency-dependent selection caused by a balance of intraspecific competition and frequency-independent stabilizing selection. This trait also acts as mating character for assortment. It has been established previously that speciation can occur only if competition is strong enough to induce disruptive selection. We find that speciation becomes more difficult for very strong competition, because then extremely strong assortment is required. Thus, speciation is most likely for intermediate strengths of competition, where it requires strong, but not extremely strong, assortment. For this range of parameters, however, it is not obvious how assortment can evolve from low to high levels, because with moderately strong assortment less genetic variation is maintained than under weak or strong assortment sometimes none at all. In addition to the strength of frequency-dependent competition and assortative mating, the roles of the number of loci, the distribution of allelic effects, the initial conditions, costs to being choosy, the strength of stabilizing selection, and the particular choice of the fitness function are explored. A multitude of possible evolutionary outcomes is observed, including loss of all genetic variation, splitting in two to five species, as well as very short and extremely long stable limit cycles. On the methodological side, we propose quantitative measures for deciding whether a given distribution reflects two (or more) reproductively isolated clusters. [source] MULTIVARIATE QUANTITATIVE GENETICS AND THE LEK PARADOX: GENETIC VARIANCE IN MALE SEXUALLY SELECTED TRAITS OF DROSOPHILA SERRATA UNDER FIELD CONDITIONSEVOLUTION, Issue 12 2004Emma Hine Abstract Single male sexually selected traits have been found to exhibit substantial genetic variance, even though natural and sexual selection are predicted to deplete genetic variance in these traits. We tested whether genetic variance in multiple male display traits of Drosophila serrata was maintained under field conditions. A breeding design involving 300 field-reared males and their laboratory-reared offspring allowed the estimation of the genetic variance-covariance matrix for six male cuticular hydrocarbons (CHCs) under field conditions. Despite individual CHCs displaying substantial genetic variance under field conditions, the vast majority of genetic variance in CHCs was not closely associated with the direction of sexual selection measured on field phenotypes. Relative concentrations of three CHCs correlated positively with body size in the field, but not under laboratory conditions, suggesting condition-dependent expression of CHCs under field conditions. Therefore condition dependence may not maintain genetic variance in preferred combinations of male CHCs under field conditions, suggesting that the large mutational target supplied by the evolution of condition dependence may not provide a solution to the lek paradox in this species. Sustained sexual selection may be adequate to deplete genetic variance in the direction of selection, perhaps as a consequence of the low rate of favorable mutations expected in multiple trait systems. [source] ENVIRONMENTAL CONDITIONS AFFECT THE MAGNITUDE OF INBREEDING DEPRESSION IN SURVIVAL OF DARWIN'S FINCHESEVOLUTION, Issue 6 2002Lukas F. Keller Abstract Understanding the fitness consequences of inbreeding (inbreeding depression) is of importance to evolutionary and conservation biology. There is ample evidence for inbreeding depression in captivity, and data from wild populations are accumulating. However, we still lack a good quantitative understanding of inbreeding depression and what influences its magnitude in natural populations. Specifically, the relationship between the magnitude of inbreeding depression and environmental severity is unclear. We quantified inbreeding depression in survival and reproduction in populations of cactus finches (Geospiza scandens) and medium ground finches (Geospiza fortis) living on Isla Daphne Major in the Galapagos Archipelago. Our analyses showed that inbreeding strongly reduced the recruitment probability (probability of breeding given that an adult is alive) in both species. Additionally, in G. scandens, first-year survival of an offspring withf= 0.25 was reduced by 21% and adults withf= 0.25 experienced a 45% reduction in their annual probability of survival. The magnitude of inbreeding depression in both adult and juvenile survival of this species was strongly modified by two environmental conditions, food availability and number of competitors. In juveniles, inbreeding depression was only present in years with low food availability, and in adults inbreeding depression was five times more severe in years with low food availability and large population sizes. The combination of relatively severe inbreeding depression in survival and the reduced recruitment probability led to the fact that very few inbred G. scandens ever succeeded in breeding. Other than recruitment probability, no other trait showed evidence of inbreeding depression in G. fortis, probably for two reasons: a relatively high rate of extrapair paternity (20%), which may lead to an underestimate of the apparent inbreeding depression, and low sample sizes of highly inbred G. fortis, which leads to low statistical power. Using data from juvenile survival, we estimated the number of lethal equivalents carried by G. scandens, G. fortis, and another congener, G. magnirostris. These results suggest that substantial inbreeding depression can exist in insular populations of birds, and that the magnitude of the inbreeding depression is a function of environmental conditions. [source] METEOROLOGICAL CONDITIONS DURING SLUSH-FLOW RELEASE AND THEIR GEOMORPHOLOGICAL IMPACT IN NORTHWESTERN ICELAND: A CASE STUDY FROM THE BÍLDUDALUR VALLEYGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2006ARMELLE DECAULNE ABSTRACT. This paper examines triggering factors and geomorphic significance of slush flows in the Bíldudalur valley, northwestern Iceland. The area is prone to release slush flows from two confined gullies, and at least ten flows have been reported since the beginning of the twentieth century. Despite their short path (600 m) and their moderate magnitude (from 6000 to 8000 m3), slush flows in the Bíldudalur valley represent a serious threat for the local community that is situated within the runout and deposition zones. With the help of meteorological data, the release of known slush flows is examined, highlighting the role of heavy rainfall and rapid snow-melt during winter cyclonic activity. The geomorphological impact of slush flows is assessed through the characteristics of the landforms produced during the 1997 and 1998 slush-flow events. It appears that the most obvious characteristics of slush flows in the Bíldudalur valley are the entrainment and deposition of debris, spatially differentiated. Chaotic sedimentation occurs chiefly in the middle part of a clearly concave cone, even if the flows continue beyond the cone. [source] PLASMA BRAIN NATRIURETIC PEPTIDE MEASURED IN STABLE CONDITIONS IS RELATED TO MORTALITY IN FRAIL AND VERY OLD PATIENTSJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2009Franck Lebourgeois MD No abstract is available for this article. [source] ANALYSIS OF VARIABLES AND MODELING OF GEVUINA AVELLANA OIL EXTRACTION WITH ETHANOL NEAR AZEOTROPE CONDITIONSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2009DANIEL FRANCO ABSTRACT Oil extraction from Gevuina avellana Mol. (Chilean hazelnut) with ethanol, near the conditions of its azeotrope with water, was carried out in this work. The effects of solubility, liquid-to-solid ratio and moisture content of ethanol were studied using 92% ethanol, azeotropic (96%) and absolute ethanol (99.9%) as solvents. Water content had a high effect on oil solubility, which reached 140 g/L in 99.9% ethanol, whereas it was 40 g/L with azeotropic ethanol. Oil accounted for 93% of total extractable compounds with absolute ethanol. Kinetics studies of the extraction process were performed at 50C, giving as a result apparent diffusivity values near 10,11 m2/s, being the highest values obtained for ethanol 92% (7.5,16 × 10,11). It was also found that the higher the liquid-to-solid ratio, the higher the diffusivity. Simulation of four-stage countercurrent extraction with azeotropic ethanol yielded 23.5% oil extraction, whereas simulation of four-stage cross-flow extraction yielded 40.7%. Ethanol can be an alternative to batch cold pressing or hexane solvent extraction, for G. savellana seeds or meal processing. PRACTICAL APPLICATIONS The results presented in this paper are applicable for obtaining oil from oilseeds by extraction with ethanol. It includes relevant results for the optimization of extraction conditions and particularly those regarding liquid-to-solid ratio and percentage of water. Considering the more specific focus of this research, the results are applicable to obtaining Gevuina avellana oil by using an ethanol-based process, which will allow to avoid one of the cold-pressing process drawbacks: the high oil content of the meal, which is a factor limiting its lifetime. [source] CONCENTRATION BOUNDARY CONDITIONS IN THE THEORETICAL ANALYSIS OF CONVECTIVE DRYING PROCESSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2007AHMET KAYA ABSTRACT In the theoretical analysis of convective drying process, two boundary conditions are common for concentration: constant concentration and convection. In this study, these two boundary conditions were comparatively examined by comparing theoretical results obtained with regard to experimental ones. Pumpkin (Cucurbita pepo) was considered as the product to be dried while air was the drying medium. The drying characteristics of pumpkin were determined for various values of drying air parameters, including temperature, velocity and relative humidity. Sorption isotherms of the dried pumpkin were also determined for different temperatures and water activities. The values of the effective moisture diffusivity, Deff, and the convective mass transfer coefficient, hm, were predicted, and these values were found to agree fairly well with those available in the existing literature. PRACTICAL APPLICATIONS Convective drying as well as other drying techniques are used in order to preserve and store agricultural products for longer periods by removing some of their moisture content. Drying is a complicated process involving simultaneous heat and mass transfer under transient conditions. Understanding the heat and mass transfer in the product will help to improve drying process parameters and hence the quality. [source] A NUMERICAL APPROACH WITH VARIABLE TEMPERATURE BOUNDARY CONDITIONS TO DETERMINE THE EFFECTIVE HEAT TRANSFER COEFFICIENT VALUES DURING BAKING OF COOKIESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2006EREN DEMIRKOL ABSTRACT The increasing trade of ready-to-eat foods such as cookies highlights an interest in quality defects during baking. Heat (h and thermal diffusivity) and mass (mass transfer and diffusion coefficients) transfer parameters are significant parameters affecting the quality changes. Therefore, it is important to determine these parameters for modeling and process optimization studies. Among these, the h is important, revealing the relationship between the heating medium and product surface. As baking involves a simultaneous heat and mass transfer involving moisture diffusion and heat conduction inside and convective heat and mass transfer outside, a lumped system method may not be an accurate choice to determine the h value. Changes in the product volume and contact heating from bottom of the product also bring extra challenges to the determination of h. Therefore, the objective of this study was to use realistic approaches including simultaneous heat and mass transfer to determine the changes in h. The heffvalues for the bottom and top surface of the cookies were then determined, applying a numerical procedure where the surface temperature changes were the boundary conditions with evaporation on the surface. The hband ht values increased with baking temperature and varied with baking time. The results of this study showed that evaporative mass flux for the top surface, heat flux for the bottom surface and the product's volume changes were significant in the variation of h values. [source] SUPERHEATED STEAM-DRYING OF MATE LEAVES AND EFFECT OF DRYING CONDITIONS ON THE PHENOL CONTENTJOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2006EVERTON FERNANDO ZANOELO ABSTRACT Four drying experiments of mate leaves (Ilex paraguariensis St. Hilaire) were carried out in a packed bed superheated steam dryer by varying outlet steam temperature from 120 to 140C and equivalent particle diameter from 4.7 × 10,3 to 6.95 × 10,3 m. The influence of these variables on the drying coefficient calculated by assuming a simplified drying kinetic model was investigated. A classical statistical approach revealed the significant effect of both factors on this parameter. Two additional drying runs were performed at identical conditions with conventional hot air and low pressure superheated steam, respectively. The influence of drying atmosphere on the total content of phenols was evaluated. A conventional process of extraction by using an aqueous methanol solution was adopted. Analyses for total phenols were performed by spectrophotometry at 715 nm by applying Folin-Denis assay. The leaves dried with superheated steam had approximately 47% higher retention of these compounds. [source] PRESSURE DROP and FRICTION FACTOR IN HELICAL HEAT EXCHANGERS UNDER NONISOTHERMAL and TURBULENT FLOW CONDITIONS,JOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2003P. CORONEL ABSTRACT This study involved the determination of pressure drop and friction factor (f) in helical heat exchangers under turbulent flow conditions. the experiments were conducted in helical heat exchangers, with coils of two different curvatures ratios (d/D = 0.114 and 0.078) at various flow rates (9.46 × 10,5 - 6.31 × 10,4 m3/s) and end-point temperatures (20, 93.3, 121, 149C). the computed friction factor (f) in the helical heat exchanger was compared to published correlations, and it was found that the experimental data was in good agreement with them. In addition, correlations to determine pressure drop based on the Reynolds number, curvature ratio, and temperature were developed. [source] RADIO FREQUENCY (RF) HEATING OF STARCH SOLUTIONS UNDER CONTINUOUS FLOW CONDITIONS: EFFECT OF SYSTEM AND PRODUCT PARAMETERS ON TEMPERATURE CHANGE ACROSS THE APPLICATOR TUBEJOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2002G.B. AWUAH ABSTRACT Studies were conducted to evaluate the effect of system and product parameters on the temperature change (,T) across a 1.5 kW radio frequency heater operating at 27.12 MHz. Starch solutions (1 to 4% w/w) were used at three different flow rates (0.35, 0.5 and 1 L/min) and four power levels (672, 912, 1152 and 1392 W). The average heating rate of starch solutions varied from 6 to 19C/min depending on flow rate, concentration and power level. The corresponding residence time varied from 1.5 to 4.3 min. Central composite designs involving power (830 to 1234 W) and starch concentration (1 to 4% w/w) at 0.5 L/min were used to study the effects of salt, pH and sugar. As expected fluid flow rate, power level and salt concentration had significant impact (P ± 0.05) on temperature change (,T) across the applicator tube. Although the interaction effect of salt and concentration influenced ,T (P < 0.05), observed trends were not clear cut. Sugar and pH had no significant (P >0.05) influence on ,T due probably to their relatively lower conductivities. However, the interaction effect of sugar and starch concentration affected ,T. Correlations were developed for estimating ,T across the tube as a function of power level, concentration, pH, added salt and sugar. Finally, dimensionless correlations involving the generalized Reynolds, Prandtl, Grashof numbers, dimensionless power and loss-factor ratios were developed for estimating the temperature ratio (U) across the RF applicator. [source] RHEOLOGICAL CHARACTERIZATION OF CARBOXYMETHYLCELLULOSE SOLUTION UNDER ASEPTIC PROCESSING CONDITIONSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2002ANDRIANA E. VAIS ABSTRACT The rheology of Carboxymethylcellulose (CMC) solutions, which are widely used as carrier fluids in aseptic processing simulations, was studied. Effects such as time dependency, recovery, and viscoelasticity were studied. A model was developed to determine the apparent viscosity of CMC solutions as a function of shear rate, temperature, and concentration. The model can be used in process design from both a fluid mechanics standpoint and a heat transfer standpoint. It was found that the solutions behaved as pseudoplastic fluids that were irreversibly thixotropic and also viscoelastic. [source] EFFECTS OF PROCESS VARIABLE CONDITIONS ON MINERAL AND CHEMICAL COMPOSITION OF EXTRUDED AFRICAN BREADFRUIT (TRECULIA AFRICANA DECNE) MIXTURESJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2009TITUS U. NWABUEZE ABSTRACT Five levels of African breadfruit (Treculia africana), corn and soybean mixtures (fc) in ratios of 40:5:55, 55:5:40, 70:5:25, 85:5:10 and 100:0:0, respectively, were hydrated to 15, 18, 21, 24 and 27% (fm) and extruded at 100, 120, 140, 160 and 180 rpm (ss) in a Brabender single-screw extruder. The objective was to study effects of process variable conditions on mineral and chemical composition of the mixtures. Models developed by response surface analysis were high (R2 = 0.7646,0.9732) for Na, Ca, Mg, protein, fat, fiber and carbohydrate, and showed no significant (P > 0.05) lack of fit. All process variables had significant (P , 0.05) linear effects on Mg, protein and carbohydrate, quadratic effects on fat, energy and Mg and cross-product effects on Ca, Mg, protein and carbohydrate, when fc interacted with either fm or ss. Optimum process variable conditions that gave the best mineral and chemical composition were obtained at 40:5:55(fc), 18% (fm) and 140 rpm (ss). PRACTICAL APPLICATIONS The potentials of African breadfruit as a nutrient resource and its position in the food cycle of the people in the subtropical African countries makes its blending with other local ingredients one important way of expanding the scope of its utilization. African breadfruit seeds provide a delicacy and a specialized meal when consumed alone or with shelled milk-corn. The versatility and acceptance of extrusion as a processing technology and its benefits over conventional methods and worldwide adaptability to a variety of crops, makes its application in this research appropriate. Optimization of process variable conditions affecting mineral and chemical composition of extruded and unextruded mixtures of African breadfruit, corn and soybean, using response surface analysis, was the thrust of the study. It is expected to produce an optimum process combination that could give the best mineral and chemical composition for a possible scale-up operation in African breadfruit seed processing enterprises. [source] OPTIMAL CONDITIONS FOR THE GROWTH AND POLYSACCHARIDE PRODUCTION BY HYPSIZIGUS MARMOREUS IN SUBMERGED CULTUREJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2009PING WANG ABSTRACTS In submerged cultivation, many nutrient variables and environmental conditions have great influence on the growth and polysaccharide production by Hypsizigus marmoreus. Plackett,Burman design was used to determine the important nutrient factors. A central composite experimental design and surface response methodology were employed to optimize the factor levels. Prediction models for dry cell weight (DCW), polysaccharide outside cells (EPS) and polysaccharide inside cells (IPS) under important nutrient conditions were developed by multiple regression analysis and verified. By solving the equations, the optimal nutrient conditions for highest EPS production (9.62 g/L) were obtained at 6.77 g cornstarch/L, 36.57 g glucose/L, 3.5 g MgSO4/L and 6.14 g bean cake powder/L, under which DCW and IPS were 16.2 g/L and 1.46 g/L, close to the highest value under their corresponding optimal conditions. Optimal environmental conditions were obtained at 10% inoculation dose, 45 mL medium in a 250 mL flask, pH 6.5, 25C and 200 rpm according to the results of single-factor experiment design. PRACTICAL APPLICATIONS Hypsizigus marmoreus polysaccharides have many functional properties, including antitumor, antifungal and antiproliferative activities, and free-radical scavenging. Liquid cultivation could produce a higher yield of polysaccharides and more flexible sequential processing methods of H. marmoreus, compared with traditional solid-state cultivation. However, the cell growth and production of polysaccharides would be influenced by many factors, including nutrient conditions and environmental conditions in the liquid cultivation of H. marmoreus. Keeping the conditions at optimal levels can maximize the yield of polysaccharides. The study not only found out the optimal nutrient conditions and environmental conditions for highest cell growth and yield of polysaccharides, but also developed prediction models for these parameters with important nutrient variables. Yield of polysaccharide inside of cells was also studied as well as polysaccharides outside of cells and cell growth. The results provide essential information for production of H. marmoreus polysaccharides by liquid culture. [source] SELECTED DRYING CONDITIONS AND STORAGE PERIOD AND QUALITY OF WALNUT SELECTIONSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2003M. A. KOYUNCU Walnut selections were hulled at harvest time, and 3 and 5 days after harvest to determine the effects of hulling time on postharvest quality. Walnuts removed from their hulls were stored shelled and unshelled under ambient conditions after being dried at selected conditions. Among the tested hulling dates, the best results were obtained from the walnuts hulled at harvest time. At the end of the storage period, the least quality losses were determined in the walnuts dried in the sun. Generally, quality losses in the shelled walnuts were greater than quality losses in the unshelled walnuts. According to the research results, walnuts removed from their hulls and dried under sun can be stored under ambient conditions (21 ± 1C and 50,65 RH) and retain acceptable quality for 12 months. [source] EFFECTS OF EXTRUSION CONDITIONS ON PHYSICOCHEMICAL PROPERTIES OF A MUTANT RICE CULTIVAR, GOAMI2 , HIGH IN NONDIGESTIBLE CARBOHYDRATESJOURNAL OF FOOD QUALITY, Issue 5 2008I. CHOI ABSTRACT A mutant rice Goami2, a cultivar high in nondigestible carbohydrates (NDCs), was extrusion-cooked at feed moisture (20, 25%), screw speed (200, 300 rpm) and barrel temperature (110, 120 and 130C). Effects of extrusion conditions on the physical and functional properties were investigated. NDCs were determined by total dietary fiber (TDF) and resistant starch (RS) contents. Increasing moisture resulted in an increment of density, water absorption index (WAI) and hardness, and a decrement in expansion and water solubility index (WSI). A higher barrel temperature decreased the hardness and increased the WSI probably due to a higher proportion of gelatinized starch. Extrusion caused a reduction in TDF in the extrudates, as well as a significant decrease in RS contents. However, extrudates processed at moisture (%), screw speed (rpm) and barrel temperature (C) combinations of 25/200/110 and 25/200/120 showed no significant difference in TDF contents compared with its raw rice. Multiple regression models showed that feed moisture had the most pronounced effect on extrudate qualities, followed by barrel temperature and screw speed. PRACTICAL APPLICATIONS Rice, being one of the primary dietary sources of carbohydrates worldwide, is the major energy and nutritional sources. In recent years, demands have been increasing for rice with a wide range of value-added properties, such as enhanced nutrient, aroma, color and rice kernel shape, including functional properties. Goami2 is a mutant rice of Ilpumbyeo, a high japonica rice cultivar, and has been revealed to have higher nondigestible fractions. However, Goami2 rice has unsuitable properties for traditional cooking because of the difficulty of gelatinization, which might result in a hard texture of cooked rice compared with that of ordinary rice. On the basis of its nutritional and functional benefits, exploiting the possible utilization of Goami2 for processed food products would increase the potential consumption of Goami2 for various food products. [source] EFFECT OF DIFFERENT STORAGE CONDITIONS ON THE LIPID FRACTION OF A VEGETABLE CREAMJOURNAL OF FOOD QUALITY, Issue 4 2008FEDERICO FERIOLI ABSTRACT Fatty acids (free and esterified), diglycerides, peroxides and total sterols were determined in a vegetable cream. Cream samples were analyzed when fresh and after storage for 3 and 6 months at 4, 15, 30C and room temperature (10,25C). The product showed a higher amount of unsaturated fatty acids (,50% of total fatty acids) with respect to milk fat and a low level of cholesterol (<0.01%). The phytosterol content (,14 mg/100 g of cream) was not high enough to contribute to a decrease in cholesterolemia. Lipid oxidation remained low during storage (peroxides: 2.0,3.0 meq O2/kg of fat), but a small increase was observed at room temperature after 6 months (about 6.0 meq O2/kg of fat). Free fatty acids never exceeded 0.3% of fat. Storage at 4C and 15C delayed lipolysis in comparison to storage at 30C and room temperature. PRACTICAL APPLICATIONS The analysis of a vegetable cream demonstrated that it was a shelf-stable product, showing a high stability toward lipid oxidation and lipolysis. Such a product might be employed as vehicle for healthy fat compounds like long-chain polyunsaturated fatty acids, phytosterols and fat-soluble vitamins. [source] EFFECT OF STORAGE CONDITIONS ON THE SENSORY QUALITY OF GROUND ARABICA COFFEEJOURNAL OF FOOD QUALITY, Issue 6 2006CAROLYN F. ROSS ABSTRACT The objective of this study was to determine how long ground coffee beans could be stored at room and freezing temperatures before sensory changes could be detected, and to identify specific attribute changes associated with this storage. Ground beans were stored for 0 (fresh), 1, 2 and 3 weeks at room and freezing temperatures. Coffee was prepared from each of these treatments and difference testing was performed. Paired comparison tests were conducted on the fresh, 1- and 2-week-stored coffee grounds to examine the attributes of coffee aroma, flavor, bitterness and overall preference. At room temperature storage, results indicated significant (P < 0.05) differences in the coffee prepared from fresh versus the 2-week-stored ground beans. Coffee made from freshly ground beans had a stronger coffee aroma, less bitterness and was more preferred compared with the beans stored for 1 or 2 weeks (P < 0.05). At freezer storage, differences were detected between coffee prepared from coffee grounds stored for 1 or 2 weeks. Coffee prepared from grounds stored for 2 weeks had a stronger coffee aroma and was more bitter compared with the other storage times (P < 0.05). [source] OPTIMIZATION OF SPRAY DRYING CONDITIONS FOR PRODUCTION OF BIFIDUS MILK POWDER FROM COW MILKJOURNAL OF FOOD QUALITY, Issue 4 2006M. SELVAMUTHUKUMARAN ABSTRACT Bifidus milk powder was prepared by supplementing cow's milk with predetermined level of additives to obtain slurry of desired concentration. The slurry was sterilized, cooled and inoculated with 24-h-old bulk culture of Bifidobacterium bifidum at 10% and incubated at 37C for 24 h, cooled and dried in SM Scientech Lab model spray dryer with predetermined spray drying conditions. The bifidus milk powder contains bifidobacteria counts from 1.88 × 109 to 15.80 × 109 cells/g dry weight and their percent survival was 4.17,35.11%. Maximum survival was obtained by using the following spray drying conditions: inlet temperature of 164.02C, slurry concentration of 25.62% total soluble solids and air pressure of 2.5 kg/cm2. The high temperature and air pressure of spray drying markedly influenced the color and appearance of final product. The inlet temperature and air pressure showed a significant effect on survival of bifidobacteria in the final product. [source] EFFECT OF STORAGE PERIOD AND EXPOSURE CONDITIONS ON THE QUALITY OF BOSANA EXTRA-VIRGIN OLIVE OILJOURNAL OF FOOD QUALITY, Issue 2 2006VINCENZO VACCA ABSTRACT Changes in quality parameters, antioxidant compounds, oxidative stability and antioxidant activity during 18 months of storage of a monovarietal extra-virgin olive oil from Bosana cultivar, and exposed to light and dark, were studied. Analysis of data showed that all the parameters underwent significant changes during storage: free acidity, peroxide and ultraviolet (UV) spectrophotometric indexes remained below the limits reported in the EEC Regulations 2568/91 and 1989/03, and these are: ,0.8% for acidity, ,20 meq O2/kg for peroxide and ,2.50 and ,0.22 for K232 and K270, respectively. Phenol and, -tocopherol content decreased during storage (42.0 and 29.6%, respectively) while chlorophylls and carotenoids underwent a decrease until 8 months of storage (49% and 30%, respectively); after that, the values remained constant. Oxidative stability and antioxidant activity had not changed dramatically during 18 months. Phenols were significantly correlated to the antioxidant activity of the oil, while oxidative stability measured by Rancimat did not show any correlation with carotenoids, chlorophylls, phenols and, -tocopherol. Regarding exposure conditions, storage in the dark was better in retaining the quality of the oil, as expected. [source] | ||||||||||||||||||||||||||||||||||||||||