Current Protocols in Food Analytical ChemistryVolume 10, Issue 1 p. B2.2.1-B2.2.14 UNIT Evaluation of the Progress of Protein Hydrolysis M. Angeles Navarrete del Toro, M. Angeles Navarrete del Toro Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, MexicoSearch for more papers by this authorFernando L. García-Carreño, Fernando L. García-Carreño Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, MexicoSearch for more papers by this author M. Angeles Navarrete del Toro, M. Angeles Navarrete del Toro Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, MexicoSearch for more papers by this authorFernando L. García-Carreño, Fernando L. García-Carreño Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, MexicoSearch for more papers by this author First published: 01 February 2004 https://doi.org/10.1002/0471142913.fab0202s10Citations: 13Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature RelatedInformation
Water holding capacity (WHC) has been traditionally measured using a wide variety of techniques, some of which measure very different aspects of water retention. Water uptake ability and expressible moisture measure two such different properties in a practical way that can be used in both industry and research. A third measurement, drip loss, can be applied to raw, cooked, frozen, and otherwise processed samples.
Chemical and physical approaches to monitoring enzyme activity are illustrated using polygalacturonase as the focus enzyme. Polygalacturonase is a depolymerase that catalyzes the hydrolysis of 1,4-glycosidic linkages in linear homogalacturonan regions of pectic polymers. Activity measurements of this enzyme may be based on the generation of new product, such as the generation of reducing sugars, or changes in the rheological properties of the polymer that result as a consequence of catalysis. Two basic assay protocols, reducing sugar- and viscosity-based assays, are presented here. Discussions of approaches to enzyme extraction and critical parameters for maintaining assay specificity are included.
Fluorescence spectra of proteins are determined chiefly by the polarity of the environment of the tryptophan and tyrosine residues and by their specific interactions. A thorough consideration of fluorescence spectrometers and their calibration is provided along with important information regarding spectrometer cells, buffers and clarification of samples. Protocols are provided for recording fluorescence spectra and for measuring fluorescence quenching to probe the accessibility of tryptophan residues to small molecules (to yield information about the structural environment of the tryptophan). The technique involves quantifying the decrease in protein fluorescence intensity in the presence of increasing concentrations of quencher, followed by analysis of the data to give details of the interaction of the quencher with the tryptophan residue. Finally, a gives details on how to interpret fluorescence spectra.
Current Protocols in Food Analytical ChemistryVolume 7, Issue 1 p. D3.6.1-D3.6.16 UNIT Static and Dynamic Interfacial Tension Analysis Jochen Weiss, Jochen Weiss University of Tennessee, Knoxville, TennesseeSearch for more papers by this author Jochen Weiss, Jochen Weiss University of Tennessee, Knoxville, TennesseeSearch for more papers by this author First published: 01 May 2003 https://doi.org/10.1002/0471142913.fad0306s07Citations: 3Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature RelatedInformation
Among numerous methods reported in the literature for analysis of protein hydrophobicty, the only methods of potential use for routine food analysis were chosen here. The most popular methods are probe spectrofluorometry using ANS, CPA, DPH, and Prodan. Additional methods selected were SDS binding, hydrophobic interaction chromatography, contact angle, and hydrophobic partition. All methods are relatively easy to conduct when need has arisen to confirm controversial data, such as those obtained by using probe spectrofluorometry. Advantages and disadvantages of different methods are compared. Importance of the relationships with functionality of proteins in food processing is emphasized because the true meaning of surface hydrophobicity of proteins is difficult to define.
This section provides an introduction to food protein functionality testing. Factors that must be considered when devising or selecting a valid testing method are summarized.
Current Protocols in Food Analytical ChemistryVolume 9, Issue 1 p. D1.7.1-D1.7.7 UNIT Infrared Spectroscopic Determination of Total Trans Fatty Acids Magdi M. Mossoba, Magdi M. Mossoba Food and Drug Administration, College Park, MarylandSearch for more papers by this authorRichard E. McDonald, Richard E. McDonald Food and Drug Administration, College Park, MarylandSearch for more papers by this author Magdi M. Mossoba, Magdi M. Mossoba Food and Drug Administration, College Park, MarylandSearch for more papers by this authorRichard E. McDonald, Richard E. McDonald Food and Drug Administration, College Park, MarylandSearch for more papers by this author First published: 01 February 2004 https://doi.org/10.1002/0471142913.fad0107s09Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat RelatedInformation
Current Protocols in Food Analytical ChemistryVolume 7, Issue 1 p. D1.1.1-D1.1.11 UNIT Extraction and Measurement of Total Lipids Fereidoon Shahidi, Fereidoon Shahidi Memorial University of Newfoundland, St. John's, Newfoundland, CanadaSearch for more papers by this author Fereidoon Shahidi, Fereidoon Shahidi Memorial University of Newfoundland, St. John's, Newfoundland, CanadaSearch for more papers by this author First published: 01 May 2003 https://doi.org/10.1002/0471142913.fad0101s07Citations: 11Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature RelatedInformation
Current Protocols in Food Analytical ChemistryVolume 9, Issue 1 p. F1.4.1-F1.4.23 UNIT Characterization of Anthocyanins by NMR Øyvind M. Andersen, Øyvind M. Andersen University of Bergen, Bergen, NorwaySearch for more papers by this authorTorgils Fossen, Torgils Fossen University of Bergen, Bergen, NorwaySearch for more papers by this author Øyvind M. Andersen, Øyvind M. Andersen University of Bergen, Bergen, NorwaySearch for more papers by this authorTorgils Fossen, Torgils Fossen University of Bergen, Bergen, NorwaySearch for more papers by this author First published: 01 February 2004 https://doi.org/10.1002/0471142913.faf0104s09Citations: 12Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature RelatedInformation
Current Protocols in Food Analytical ChemistryVolume 7, Issue 1 p. H3.1.1-H3.1.11 UNIT Dynamic or Oscillatory Testing of Complex Fluids Peter Whittingstall, Peter Whittingstall ConAgra Foods, Irvine, CaliforniaSearch for more papers by this author Peter Whittingstall, Peter Whittingstall ConAgra Foods, Irvine, CaliforniaSearch for more papers by this author First published: 01 May 2003 https://doi.org/10.1002/0471142913.fah0301s07Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat RelatedInformation
Current Protocols in Food Analytical ChemistryVolume 7, Issue 1 p. D1.6.1-D1.6.14 UNIT Quantitation of Lipid Classes by Thin-Layer Chromatography with Flame Ionization Detection Shengying Zhou, Shengying Zhou The Minute Maid Company, Apopka, FloridaSearch for more papers by this author Shengying Zhou, Shengying Zhou The Minute Maid Company, Apopka, FloridaSearch for more papers by this author First published: 01 May 2003 https://doi.org/10.1002/0471142913.fad0106s07Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature RelatedInformation
Increasing evidence suggests that consumption of soybean products may have a significant impact upon health. The biological activity has been associated, in part, with the presence of isoflavones in soy. Analysis of these bioactive compounds in soybean products is an essential part of any research involving soy isoflavones. Various processing conditions produce soy products with a wide range of isoflavone content and composition. Recent studies demonstrated that the chemical forms and abundance of isoflavones in soy foods have a significant impact on their bioavailability and biological effects. It is thus very important to avoid altering the natural forms and abundance of the twelve soy isoflavones during extraction, identification, and quantification. In this unit, an attempt has been made to provide reliable protocols with the most commonly used analytical techniques for this purpose.
This article discusses the use of step-change tests in rheometry of foods. A step change test allows for a material to be probed in its linear viscoelastic region, and beyond, where deformation is no longer reversible. This irreversible deformation behavior is of interest as it marks the onset of flow and can therefore shed light on the yield or failure of materials. Keywords: rheology; creep; stress relaxation; relaxation time
AbstractRefractometric and hydrometric measurements have long been used as means of estimating solution concentrations. The effectiveness of their use to measure equivalent concentration (°Brix) is discussed. The approximations inherent in the use of such traditional methods to estimate water content are highlighted.
Current Protocols in Food Analytical ChemistryVolume 00, Issue 1 p. A1.1.1-A1.1.1 UNIT Gravimetric Determination of Water by Drying and Weighing Rennie P. Ruiz, Rennie P. Ruiz Hunt-Wesson, Inc, Fullerton, CaliforniaSearch for more papers by this author Rennie P. Ruiz, Rennie P. Ruiz Hunt-Wesson, Inc, Fullerton, CaliforniaSearch for more papers by this author First published: 01 August 2001 https://doi.org/10.1002/0471142913.faa0101s00Citations: 9Read the full textAbout ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Literature Cited Davis, A.B. and Lai, C.S. 1984. Microwave utilization in the rapid determination of flour moisture Cereal Chem. 61: 1-4. Web of Science®Google Scholar Karmas, E. 1980. Techniques for measurement of moisture content of foods. Food Techno. 34: 52-59. Web of Science®Google Scholar Okabe, T., Huang, M.T., and Okamura, S. 1973. A new method for the measurement of grain moisture content by the use of microwaves J. Agric. Eng. Res 18: 59-64. 10.1016/0021-8634(73)90033-4 Web of Science®Google Scholar D.M. Sullivan and D.E. Carpenter (eds.) 1993. Methods of Analysis for Nutritional Labeling. Association of Official Analytical Chemists (AOAC) International, Arlington, Va. Google Scholar Key References American Association of Cereal Chemists, Inc. 1995. Approved Methods of the AACC, 9th ed. American Association of Cereal Chemists (AACC), Inc., St. Paul, Minn. Google Scholar Current methodologies for use on grains and grain products recognized by the AACC, including moisture analyses based on convection, vacuum, and microwave ovens. P. Cunniff (ed.) 1998. Official Methods of Analysis of the Association of Official Analytical Chemists, 16th ed., 4th revision. AOAC International, Gaithersburg, Md. Google Scholar Current methodologies for use on foods and nonfood products recognized by the AOAC, including moisture analyses based on convection, vacuum, and microwave ovens. Kirk, R.S. and Sawyer, R. 1991. Person's Composition and Analysis of Foods, 9th ed. Logman Scientific & Technical, Essex, England. Google Scholar A useful introduction to general food analysis. Pomeranz, Y. and Meloan, C.E. 1994. Food Analysis, 3rd ed. Chapman & Hall, New York. Google Scholar A useful introduction to general food analysis. Citing Literature ReferencesRelatedInformation
Current Protocols in Food Analytical ChemistryVolume 7, Issue 1 p. H3.2.1-H3.2.9 UNIT Measurement of Gel Rheology: Dynamic Tests Shinya Ikeda, Shinya Ikeda Osaka City University, Osaka, JapanSearch for more papers by this authorE. Allen Foegeding, E. Allen Foegeding North Carolina State University, Raleigh, North CarolinaSearch for more papers by this author Shinya Ikeda, Shinya Ikeda Osaka City University, Osaka, JapanSearch for more papers by this authorE. Allen Foegeding, E. Allen Foegeding North Carolina State University, Raleigh, North CarolinaSearch for more papers by this author First published: 01 May 2003 https://doi.org/10.1002/0471142913.fah0302s07Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature RelatedInformation
Volatile odorants can be analyzed by gas chromatography/olfactometry (GC/O), a collection of techniques that range from simple modifications of GC equipment to elaborate commercial GC-olfactometers and protocols. This unit describes the direct column sniffing, dilution analysis, and time intensity protocols most commonly used in the food industry.
Current Protocols in Food Analytical ChemistryVolume 7, Issue 1 p. E3.5.1-E3.5.12 UNIT Quantitative Determination of β-Glucan Content Zvonko Burkus, Zvonko Burkus University of Alberta, Edmonton, CanadaSearch for more papers by this authorFeral Temelli, Feral Temelli University of Alberta, Edmonton, CanadaSearch for more papers by this author Zvonko Burkus, Zvonko Burkus University of Alberta, Edmonton, CanadaSearch for more papers by this authorFeral Temelli, Feral Temelli University of Alberta, Edmonton, CanadaSearch for more papers by this author First published: 01 May 2003 https://doi.org/10.1002/0471142913.fae0305s07Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature RelatedInformation
