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Recovery Yield (recovery + yield)
Selected AbstractsAmino Acid and Mineral Composition of Protein and Other Components and Their Recovery Yields from Whole Antarctic Krill (Euphausia superba) Using Isoelectric Solubilization/PrecipitationJOURNAL OF FOOD SCIENCE, Issue 2 2009Y.-C. Chen ABSTRACT:, Proteins and insolubles were recovered from whole Antarctic krill via novel isoelectric solubilization/precipitation using different pH treatments. The protein recovery yield was 45% to 50% (dry basis). The recovered proteins had higher (P < 0.05) content of essential amino acids (EAAs) and non-EAAs as well as higher (P < 0.05) ratio of total EAA/total AA than whole krill. The EAAs constituted almost 50% of total AAs. The least extreme pH treatments (pHs 3 and 12) yielded highest (P < 0.05) content of EAAs. The quality of recovered proteins was high based on EAAs meeting FAO/WHO/UNU recommendations for adults and infants. The basic pH yielded proteins with the lowest (P < 0.05) amount of minerals and the highest (P < 0.05) amount of Ca, P, and Mg in the insolubles when compared to the acidic treatments. However, both basic and acidic treatments effectively removed minerals from recovered proteins without the removal of the exoskeleton before processing. Therefore, besides high-quality proteins, the insolubles may provide a mineral supplement in the animal diet. [source] Carp (Cyprinus carpio) oils obtained by fishmeal and ensilage processes: characteristics and lipid profilesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2009Valéria T. Crexi Summary Fish oil is an important source of long-chain ,-3 polyunsaturated fatty acid. The common carp (Cyprinus carp) is a major fish species in world aquaculture production. This study aimed towards obtaining carp viscera oil by ensilage and fishmeal processes. Characteristics of crude oils obtained were also compared with oil extracted by Bligh and Dyer methods. Crude oils obtained by the three processes resulted in significant difference (P < 0.05) for free fatty acids, peroxide, thiobarbituric acid and Lovibond colour values; however, iodine and saponification values were not significantly affected (P > 0.05). Recovery yield of crude oils was approximately 85% in relation to carp viscera oil. Carp crude oils obtained by the ensilage and fishmeal processes resulted in high unsaturated and polyunsaturated fatty acid contents (67.4%), and ,3/,6 ratios around 1.15. These oils are applicable in fish diets; however, crude oils require refinement for human consumption. [source] Concentration and separation of glycyrrhizic acid by foam separationJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 6 2002Jun-Gang Ma Abstract By the aid of the surface activities of glycyrrhizic acid, foam separation can be used to extract and concentrate it. The effects of operating parameters such as flow rate of air, initial feed concentration, pH and ionic strength on the enrichment ratio and recovery yield of glycyrrhizic acid are investigated in detail. In addition, the influences of other surface-active substances in solution, such as proteins, on the separation of glycyrrhizic acid are also discussed. The experimental results show that foam separation is a simple and effective method to separate and concentrate glycyrrhizic acid. © 2002 Society of Chemical Industry [source] Computational study of staged membrane reactor configurations for methane steam reforming.AICHE JOURNAL, Issue 1 2010Abstract This article and Part II report a computational study carried out to analyze the performance achievable using a staged membrane reactor in the methane steam reforming process to produce high purity hydrogen. A reaction/separation unit in which reactive stages are laid out in series to permeative stages already proposed in literature (Caravella et al., J Memb Sci. 2008;321:209,221) is modified here to increase its flexibility. The improvement includes the consideration of the Pd-based membrane along the entire length. Two- and ten-staged reactors are examined in terms of methane conversion, hydrogen recovery factor and hydrogen recovery yield, considering co- and counter-current flow configurations. Individual stage lengths are obtained by maximizing either methane conversion or hydrogen recovery yield, comparing the results to the ones of an equivalent traditional reactor and a conventional membrane reactor. The analysis allows demonstrating that the counter-current configuration leads to significant improvements in the hydrogen recovery, but proves almost irrelevant with respect to methane conversion. The influence of the number of stages and the amount of catalyst is quantified in the accompanying part II article. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Computational study of staged membrane reactor configurations for methane steam reforming.AICHE JOURNAL, Issue 1 2010Abstract The present work complements part I of this article and completes a computational analysis of the performances of staged membrane reactors for methane steam reforming. The influence of the number of stages and catalyst amount is investigated by comparing the methane conversion and hydrogen recovery yield achieved by an equisized-staged reactor to those of an equivalent conventional membrane reactor for different furnace temperatures and flow configurations (co- and counter-current). The most relevant result is that the proposed configuration with a sufficiently high number of stages and a significantly smaller catalyst amount (up to 70% lower) can achieve performances very close to the ones of the conventional unit in all the operating conditions considered. This is equivalent to say that the staged configuration can compensate and in fact substitute a significant part of the catalyst mass of a conventional membrane reactor. To help the interpretation of these results, stage-by-stage temperature and flux profiles are examined in detail. Then, the quantification of the performance losses with respect to the conventional reactor is carried out by evaluating the catalyst amount possibly saved and furnace temperature reduction. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Isotope analysis of hydrocarbons: trapping, recovering and archiving hydrocarbons and halocarbons separated from ambient airRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 4 2005M. Pupek It is argued that isotope analysis of atmospheric non-methane hydrocarbons (NMHCs) and, in particular, the analysis of the deuterium/hydrogen (D/H) ratio is valuable because the dominant self-cleansing property of the troposphere is based on the OH radical which removes, e.g., CH4 and other alkanes by H-atom abstraction, which induces large kinetic isotope effects. The major obstacle in applying D/H isotope analysis to atmospheric NMHCs is not only the low abundance of D itself but, in particular, the low concentrations of NMHCs in the parts per trillion range. We show how a selection of NMHCs can be quantitatively separated from 300,L air samples together with CO2 as carrier gas matrix, by using high efficiency cryogenic traps. After diluting the extracted NMHC mixtures with hydrocarbon free air, and determining the mixing ratios, good agreement with original whole air sample analysis exists for alkanes and several halocarbons. For unsaturated hydrocarbons and some other halocarbons the extraction and recovery yield under the given conditions fell considerably, as a function of boiling point. Furthermore, the mixture of NMHCs in the CO2 matrix is proven to remain unchanged over several years when conveniently stored in glass ampoules. The ,extracts' or ,concentrates' of condensables extracted from larger air samples will enable the D/H isotope analysis of ultra trace gases in the atmosphere. Copyright © 2005 John Wiley & Sons, Ltd. [source] Effect of surface defects in Pd-based membranes on the performance of a membrane reactorASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2010Alessio Caravella Abstract In this work, the influence of superficial defects over the surface of a Pd-based membrane is analyzed in a membrane reactor for the methane steam-reforming process. In order to include the presence of defects in the permeation, a previous model of a defect-free Pd-based membrane reactor is extended and integrated to include a variable portion of area with defects in the form of pinholes. As a consequence, two different permeation mechanisms are taken into account, one through the Pd-based surface and the other one through the pinholes, where a Knudsen-like transport is considered to occur. The presence of the Knudsen transport causes the membrane separation factor between the hydrogen and the other species involved in the process to decrease, affecting the reactor performances significantly. Three reactor performance indices are investigated as functions of the fraction of the defected area and the mean pore diameter of defects, namely methane conversion, the hydrogen recovery factor, the hydrogen recovery yield and the net purity of hydrogen in the permeate. The results show that the hydrogen recovery factor is positively influenced by the decrease in hydrogen selectivity, whilst methane conversion and hydrogen net purity decrease significantly with it. On the contrary, regarding the hydrogen recovery yield, it is shown that in certain conditions (low furnace temperature, , 550 °C) it decreases with hydrogen selectivity. However, it increases again at higher furnace temperatures (,650 °C). Globally, this investigation helps in identifying acceptable defect levels on a Pd-based membrane for methane steam-reforming applications and highlights that even a very small defect level (in terms of the pinhole diameter and/or amount of the defected area) can importantly compromise the reactor performances. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Selective Extraction of Free Astaxanthin from Haematococcus Culture Using a Tandem Organic Solvent SystemBIOTECHNOLOGY PROGRESS, Issue 4 2007Chang Duk Kang A novel tandem solvent process of dodecane and methanol was developed for the selective extraction of free astaxanthin from red encysted Haematococcus culture. The process consists of dodecane extraction for astaxanthin mixture from the culture (stage 1) and methanol extraction for free astaxanthin from the dodecane extract (stage 2). In the first stage, astaxanthin mixture was directly extracted to dodecane from the culture broth without cell harvest process, followed by a rapid separation of the dodecane extract and the culture medium containing cell debris by simple settling. In the second stage, free astaxanthin was selectively collected to methanol from the dodecane extract, accompanied with saponification of astaxanthin-esters by the addition of NaOH to methanol. During saponification, use of the optimum NaOH concentration (0.02 M) and low temperature (4 °C) reaction minimized the degradation of free astaxanthin, resulting in a total recovery yield of free astaxanthin of over 85%. The free-astaxanthin-containing methanol extract was also simply separated from dodecane by gravity settling, after which the astaxanthin-free dodecane was effectively recycled to the first stage, yielding a stable extractability of astaxanthin mixture during repeated extraction. Our results indicate the potential of the proposed tandem solvent process as an alternative extraction technology for the high-value antioxidant Haematococcus astaxanthin. [source] Recovery of water-soluble constituents of rose oil using simultaneous distillation,extractionFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2005Mohammad H. Eikani Abstract Recovery of water-soluble constituents of rose oil from aqueous solutions using simultaneous distillation,extraction was studied. Experiments were carried out using a modified Likens,Nickerson apparatus. A preliminary study was first performed on aqueous 2-phenylethanol solutions. Using n -butyl acetate as the solvent, the effects of extraction time, solvent volume and solute concentration on recovery yields were investigated. The optimum experimental conditions obtained from the preliminary study were applied to extract rose oil constituents from actual aqueous solutions, such as rose water, second distillation water and residual water of Iranian rose (Rosa damascena Mill). The results show that a representative extract with recovery of the most valuable constituents of rose oil was carried out successfully. Copyright © 2005 John Wiley & Sons, Ltd. [source] Purification and characterization of two bacteriocins produced by lactic acid bacteria isolated from Mongolian airagJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2006B. Batdorj Abstract Aims:, The aim of this study was to isolate and identify bacteriocin-producing lactic acid bacteria (LAB) issued from Mongolian airag (traditional fermented mare's milk), and to purify and characterize bacteriocins produced by these LAB. Methods and Results:, Identification of the bacteria (Enterococcus durans) was carried out on the basis of its morphological, biochemical characteristics and carbohydrate fermentation profile and by API50CH kit and 16S rDNA analyses. The pH-neutral cell-free supernatant of this bacterium inhibited the growth of several Lactobacillus spp. and food-borne pathogens including Escherichia coli, Staphylococcus aureus and Listeria innocua. The antimicrobial agent (enterocin A5-11) was heat stable and was not sensitive to acid and alkaline conditions (pH 2,10), but was sensitive to several proteolytic enzymes. Its inhibitory activity was completely eliminated after treatment with proteinase K and , -chymotrypsin. The activity was however not completely inactivated by other proteases including trypsin and pepsin. Three-step purification procedure with high recovery yields was developed to separate two bacteriocins. The applied procedure allowed the recovery of 16% and 64% of enterocins A5-11A and A5-11B, respectively, present in the culture supernatant with purity higher than 99%. SDS-PAGE analyses revealed that enterocin A5-11 has a molecular mass of 5000 Da and mass spectrometry analyses demonstrates molecular masses of 5206 and 5218 Da for fractions A and B, respectively. Amino acid analyses of both enterocins indicated significant quantitative difference in their contents in threonine, alanine, isoleucine and leucine. Their N -termini were blocked hampering straightforward Edman degradation. Conclusions:, Bacteriocins A5-11A and B from Ent. durans belong to the class II of bacteriocins. Significance and Impact of the Study:, Judging from molecular masses, amino acid composition and spectrum of activities, bacteriocins A5-11A and B from Ent. durans show high degree of similarity with enterocins L50A and L50B isolated from Enterococcus faecium (Cintas et al. 1998, 2000) and with enterocin I produced by Ent. faecium 6T1a, a strain originally isolated from a Spanish-style green olive fermentation (Floriano et al. 1998). [source] Texture and colour properties of proteins recovered from whole gutted silver carp (Hypophthalmichthys molitrix) using isoelectric solubilisation/precipitationJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2009Latif Taskaya Abstract BACKGROUND: According to an FAO report, carp are the cheapest and by far the most commonly consumed fish in the world. Carp have minimal growth requirements, yet rapid growth rates. Although carp are generally considered unsuitable for human consumption in the USA, they have rapidly started populating major bodies of fresh water in the USA to the extent that commercial processing becomes of interest. However, typical mechanical means of meat recovery from carp are impractical owing to the bony nature of the carp carcass. Therefore the aim of the present study was to devise processing strategies to recover fish meat from carp that could be used in the development of human food products. RESULTS: Isoelectric solubilisation/precipitation at acidic and basic pH values was applied to whole gutted silver carp. Depending on the solubilisation pH, protein and fat recovery yields were approximately 420,660 and 800,950 g kg,1 respectively. The process effectively removed impurities such as bones, scales, skin, fins, etc. from whole gutted carp. The proteins were concentrated to approximately 900 g kg,1, while the fat was reduced by 970,990 g kg,1. Functional additives (potato starch, beef plasma protein, transglutaminase and polyphosphate) improved (P < 0.05) the texture of carp protein-based gels such that it was generally comparable to the texture of Alaska pollock surimi gels. Although titanium dioxide improved (P < 0.05) the whiteness of carp gels, it was lower (P < 0.05) than the whiteness of Alaska pollock surimi gels. CONCLUSION: Isoelectric solublisation/precipitation allows protein and lipid recovery from whole gutted carp. However, if the proteins are used as a gelling ingredient in fish food products, functional additives are recommended. Copyright © 2008 Society of Chemical Industry [source] | |||||||||||||||||||||||||