Evaluation of sequential methods for the determination of butterfat fatty acid composition with emphasis on trans -18:1 acids. Application to the study of seasonal variations in french butters
Identifieur interne : 000084 ( Istex/Corpus ); précédent : 000083; suivant : 000085Evaluation of sequential methods for the determination of butterfat fatty acid composition with emphasis on trans -18:1 acids. Application to the study of seasonal variations in french butters
Auteurs : Robert L. Wolff ; Corinne C. Bayard ; Robert J. FabienSource :
- Journal of the American Oil Chemists’ Society [ 0003-021X ] ; 1995-12-01.
English descriptors
- KwdEn :
- Absolute values, Accurate determination, Acid, Acid analysis, Acid composition, Acid content, Acid fraction, Acid group, Acid level, Acid peak, Active carbon atoms, Ambient temperature, Annual value, Aqueous solution, Bannon, Beef meat lipids, Beef tallow, Butterfat, Butyric, Butyric acid, Butyric acid content, Capillary chromatography, Capillary column, Carbon atoms, Carlo erba, Chem, Chromatographic conditions, Climatic conditions, Coefficient, Conversion factors, Different operators, Different periods, Distribution profile, Double bonds, Elution steps, Ester, Esterification, Ethylenic bond, Ethylenic bonds, Experimental data, Experimental errors, Experimental methodology, Faipe, Faipe preparation, Faipe solutions, Fall butters, Fatty, Fatty acid, Fatty acid butyl esters, Fatty acid composition, Fatty acid isopropyl esters, Fatty acid methyl esters, Fatty acid weight percentages, Fatty acids, Fractionation, French butters, Goat cheeses, Hexane, High proportion, Hydrogenated oils, Ibid, Individual isomers, Integrator, Internal standards, Isomer, Isomeric acids, Jaocs, Late winter, Lipid, Lowest level, Maximum values, More uniform, Narrow range, Other hand, Other seasons, Palmitic, Palmitic acid, Palmitic acid esters, Partial insight, Peak area percentages, Possible variations, Present study, Previous study, Regional variations, Relative conversion factors, Retention times, Same conditions, Same sample, Seasonal variations, Second time, Several isomers, Several times, Single sample, Standard deviation, Standard deviations, Standard mixture, Standard solution, Such variations, Temperature programming, Theoretical response factor, Total acids, Total faipe, Total isomers, Trans, Trans isomers, Transmonoenoic acids, Unpublished results, Upper phase, Vaccenic, Vaccenic acid, Vertical bars, Weight percent, Weight percentage, Weight percentages, Whole procedure, Winter butter, Winter butters, Wolff etal.
- Teeft :
- Absolute values, Accurate determination, Acid, Acid analysis, Acid composition, Acid content, Acid fraction, Acid group, Acid level, Acid peak, Active carbon atoms, Ambient temperature, Annual value, Aqueous solution, Bannon, Beef meat lipids, Beef tallow, Butterfat, Butyric, Butyric acid, Butyric acid content, Capillary chromatography, Capillary column, Carbon atoms, Carlo erba, Chem, Chromatographic conditions, Climatic conditions, Coefficient, Conversion factors, Different operators, Different periods, Distribution profile, Double bonds, Elution steps, Ester, Esterification, Ethylenic bond, Ethylenic bonds, Experimental data, Experimental errors, Experimental methodology, Faipe, Faipe preparation, Faipe solutions, Fall butters, Fatty, Fatty acid, Fatty acid butyl esters, Fatty acid composition, Fatty acid isopropyl esters, Fatty acid methyl esters, Fatty acid weight percentages, Fatty acids, Fractionation, French butters, Goat cheeses, Hexane, High proportion, Hydrogenated oils, Ibid, Individual isomers, Integrator, Internal standards, Isomer, Isomeric acids, Jaocs, Late winter, Lipid, Lowest level, Maximum values, More uniform, Narrow range, Other hand, Other seasons, Palmitic, Palmitic acid, Palmitic acid esters, Partial insight, Peak area percentages, Possible variations, Present study, Previous study, Regional variations, Relative conversion factors, Retention times, Same conditions, Same sample, Seasonal variations, Second time, Several isomers, Several times, Single sample, Standard deviation, Standard deviations, Standard mixture, Standard solution, Such variations, Temperature programming, Theoretical response factor, Total acids, Total faipe, Total isomers, Trans, Trans isomers, Transmonoenoic acids, Unpublished results, Upper phase, Vaccenic, Vaccenic acid, Vertical bars, Weight percent, Weight percentage, Weight percentages, Whole procedure, Winter butter, Winter butters, Wolff etal.
Abstract
Abstract: The successive steps of an integrated analytical procedure aimed at the accurate determination of butterfat fatty acid composition, includingtrans-18:1 acid content and profile, have been carefully checked. This sequential procedure includes: dispersion of a portion of butter in hexane/isopropanol (2:1, vol/vol) with anhydrous Na2SO4, filtration of aliquots of the suspension through a microfiltration unit, subsequent preparation of fatty acid isopropyl esters (FAIPE) with H2SO4 as a catalyst, and analysis of total FAIPE by capillary gas-liquid chromatography (GLC). Isolation oftrans-18:1 isomers was by silver-ion thin-layer chromatography (Ag-TLC), followed by extraction from the gel of combined saturated andtrans-monoenoic acids with a biphasic solvent system. Analysis of these fractions by GLC allows the accurate quantitation oftrans-18:1 acids with saturated acids (14:0, 16:0, and 18:0) as internal standards. A partial insight in the distribution oftrans-18:1 isomers can be obtained by GLC on a CP Sil 88 capillary column (Chrompack, Middelburg, The Netherlands). All steps of the procedure are quite reproducible, part of the coefficients of variation (generally less than 3%, mainly limited to butyric and stearic acids) being associated with GLC analysis (injection, integration of peaks) and, to a lesser extent, to FAIPE preparation. FAIPE appear to be of greater practical interest than any other fatty acid esters, including fatty acid methyl esters (FAME), for the quantitation of short-chain fatty acids, because peak area percentages, calculated by the integrator coupled to the flame-ionization detector, are almost equal (theoretically and experimentally) to fatty acid weight percentages and do not require correction factors. With this set of procedures, we have followed in detail the seasonal variations of fatty acids in butterfat, with sixty commercial samples of French butter collected at five different periods of the year. Important variations occur around mid-April, when cows are shifted from forage and concentrates during winters spent in their stalls to fresh grass in pastures. At this period, there is a decrease of 4:0–14:0 acids and of 16:0 (−2 and −6%, respectively), while 18:0 andcis- plustrans-18:1 acids rise suddenly (2 and 5%, respectively). These modifications then progressively disappear until late fall or early winter. Other variations are of minor quantitative importance. Although influenced by the season, the content of 18:2n-6 acid lies in the narrow range of 1.2–1.5%.Trans-18:1 acids, quantitated by GLC after Ag-TLC fractionation, are at their highest level in May–June (4.3% of total fatty acids), and at their lowest level between January and the end of March (2.4%), with a mean annual value of 3.3%. The proportion of vaccenic (trans-11 18:1) acid, relative to totaltrans-18:1 isomers, is higher in spring than in winter, with intermediate decreasing values in summer and fall, which supports the hypothesis that the level of this isomer is linked to the feed of the cattle, and probably to the amount of grass in the feed.
Url:
DOI: 10.1007/BF02577840
Links to Exploration step
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<front><div type="abstract" xml:lang="en">Abstract: The successive steps of an integrated analytical procedure aimed at the accurate determination of butterfat fatty acid composition, includingtrans-18:1 acid content and profile, have been carefully checked. This sequential procedure includes: dispersion of a portion of butter in hexane/isopropanol (2:1, vol/vol) with anhydrous Na2SO4, filtration of aliquots of the suspension through a microfiltration unit, subsequent preparation of fatty acid isopropyl esters (FAIPE) with H2SO4 as a catalyst, and analysis of total FAIPE by capillary gas-liquid chromatography (GLC). Isolation oftrans-18:1 isomers was by silver-ion thin-layer chromatography (Ag-TLC), followed by extraction from the gel of combined saturated andtrans-monoenoic acids with a biphasic solvent system. Analysis of these fractions by GLC allows the accurate quantitation oftrans-18:1 acids with saturated acids (14:0, 16:0, and 18:0) as internal standards. A partial insight in the distribution oftrans-18:1 isomers can be obtained by GLC on a CP Sil 88 capillary column (Chrompack, Middelburg, The Netherlands). All steps of the procedure are quite reproducible, part of the coefficients of variation (generally less than 3%, mainly limited to butyric and stearic acids) being associated with GLC analysis (injection, integration of peaks) and, to a lesser extent, to FAIPE preparation. FAIPE appear to be of greater practical interest than any other fatty acid esters, including fatty acid methyl esters (FAME), for the quantitation of short-chain fatty acids, because peak area percentages, calculated by the integrator coupled to the flame-ionization detector, are almost equal (theoretically and experimentally) to fatty acid weight percentages and do not require correction factors. With this set of procedures, we have followed in detail the seasonal variations of fatty acids in butterfat, with sixty commercial samples of French butter collected at five different periods of the year. Important variations occur around mid-April, when cows are shifted from forage and concentrates during winters spent in their stalls to fresh grass in pastures. At this period, there is a decrease of 4:0–14:0 acids and of 16:0 (−2 and −6%, respectively), while 18:0 andcis- plustrans-18:1 acids rise suddenly (2 and 5%, respectively). These modifications then progressively disappear until late fall or early winter. Other variations are of minor quantitative importance. Although influenced by the season, the content of 18:2n-6 acid lies in the narrow range of 1.2–1.5%.Trans-18:1 acids, quantitated by GLC after Ag-TLC fractionation, are at their highest level in May–June (4.3% of total fatty acids), and at their lowest level between January and the end of March (2.4%), with a mean annual value of 3.3%. The proportion of vaccenic (trans-11 18:1) acid, relative to totaltrans-18:1 isomers, is higher in spring than in winter, with intermediate decreasing values in summer and fall, which supports the hypothesis that the level of this isomer is linked to the feed of the cattle, and probably to the amount of grass in the feed.</div>
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<Para>The successive steps of an integrated analytical procedure aimed at the accurate determination of butterfat fatty acid composition, including<Emphasis Type="Italic">trans</Emphasis>
-18:1 acid content and profile, have been carefully checked. This sequential procedure includes: dispersion of a portion of butter in hexane/isopropanol (2:1, vol/vol) with anhydrous Na<Subscript>2</Subscript>
SO<Subscript>4</Subscript>
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- plus<Emphasis Type="Italic">trans</Emphasis>
-18:1 acids rise suddenly (2 and 5%, respectively). These modifications then progressively disappear until late fall or early winter. Other variations are of minor quantitative importance. Although influenced by the season, the content of 18:2n-6 acid lies in the narrow range of 1.2–1.5%.<Emphasis Type="Italic">Trans</Emphasis>
-18:1 acids, quantitated by GLC after Ag-TLC fractionation, are at their highest level in May–June (4.3% of total fatty acids), and at their lowest level between January and the end of March (2.4%), with a mean annual value of 3.3%. The proportion of vaccenic (<Emphasis Type="Italic">trans</Emphasis>
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<Keyword>fatty acid methyl esters</Keyword>
<Keyword>flame-ionization detector</Keyword>
<Keyword>gas-liquid chromatography</Keyword>
<Keyword>response factor</Keyword>
<Keyword>seasonal variations</Keyword>
<Keyword>silver-ion thin-layer chromatography</Keyword>
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<affiliation>ISTAB, Laboratoire de Lipochimie Alimentaire, Université Bordeau 1, Allée des Facultés, 33405, Talence Cedex, France</affiliation>
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</name>
<name type="personal"><namePart type="given">Corinne</namePart>
<namePart type="given">C.</namePart>
<namePart type="family">Bayard</namePart>
<affiliation>ISTAB, Laboratoire de Lipochimie Alimentaire, Université Bordeau 1, Allée des Facultés, 33405, Talence Cedex, France</affiliation>
<role><roleTerm type="text">author</roleTerm>
</role>
</name>
<name type="personal"><namePart type="given">Robert</namePart>
<namePart type="given">J.</namePart>
<namePart type="family">Fabien</namePart>
<affiliation>Maxwell Chemicals, Botany, Australia</affiliation>
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<genre type="research-article" displayLabel="OriginalPaper" authority="ISTEX" authorityURI="https://content-type.data.istex.fr" valueURI="https://content-type.data.istex.fr/ark:/67375/XTP-1JC4F85T-7">research-article</genre>
<originInfo><publisher>Springer-Verlag</publisher>
<place><placeTerm type="text">Berlin/Heidelberg</placeTerm>
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<dateCreated encoding="w3cdtf">1995-03-31</dateCreated>
<dateIssued encoding="w3cdtf">1995-12-01</dateIssued>
<dateIssued encoding="w3cdtf">1995</dateIssued>
<copyrightDate encoding="w3cdtf">1995</copyrightDate>
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<abstract lang="en">Abstract: The successive steps of an integrated analytical procedure aimed at the accurate determination of butterfat fatty acid composition, includingtrans-18:1 acid content and profile, have been carefully checked. This sequential procedure includes: dispersion of a portion of butter in hexane/isopropanol (2:1, vol/vol) with anhydrous Na2SO4, filtration of aliquots of the suspension through a microfiltration unit, subsequent preparation of fatty acid isopropyl esters (FAIPE) with H2SO4 as a catalyst, and analysis of total FAIPE by capillary gas-liquid chromatography (GLC). Isolation oftrans-18:1 isomers was by silver-ion thin-layer chromatography (Ag-TLC), followed by extraction from the gel of combined saturated andtrans-monoenoic acids with a biphasic solvent system. Analysis of these fractions by GLC allows the accurate quantitation oftrans-18:1 acids with saturated acids (14:0, 16:0, and 18:0) as internal standards. A partial insight in the distribution oftrans-18:1 isomers can be obtained by GLC on a CP Sil 88 capillary column (Chrompack, Middelburg, The Netherlands). All steps of the procedure are quite reproducible, part of the coefficients of variation (generally less than 3%, mainly limited to butyric and stearic acids) being associated with GLC analysis (injection, integration of peaks) and, to a lesser extent, to FAIPE preparation. FAIPE appear to be of greater practical interest than any other fatty acid esters, including fatty acid methyl esters (FAME), for the quantitation of short-chain fatty acids, because peak area percentages, calculated by the integrator coupled to the flame-ionization detector, are almost equal (theoretically and experimentally) to fatty acid weight percentages and do not require correction factors. With this set of procedures, we have followed in detail the seasonal variations of fatty acids in butterfat, with sixty commercial samples of French butter collected at five different periods of the year. Important variations occur around mid-April, when cows are shifted from forage and concentrates during winters spent in their stalls to fresh grass in pastures. At this period, there is a decrease of 4:0–14:0 acids and of 16:0 (−2 and −6%, respectively), while 18:0 andcis- plustrans-18:1 acids rise suddenly (2 and 5%, respectively). These modifications then progressively disappear until late fall or early winter. Other variations are of minor quantitative importance. Although influenced by the season, the content of 18:2n-6 acid lies in the narrow range of 1.2–1.5%.Trans-18:1 acids, quantitated by GLC after Ag-TLC fractionation, are at their highest level in May–June (4.3% of total fatty acids), and at their lowest level between January and the end of March (2.4%), with a mean annual value of 3.3%. The proportion of vaccenic (trans-11 18:1) acid, relative to totaltrans-18:1 isomers, is higher in spring than in winter, with intermediate decreasing values in summer and fall, which supports the hypothesis that the level of this isomer is linked to the feed of the cattle, and probably to the amount of grass in the feed.</abstract>
<note>Article</note>
<relatedItem type="host"><titleInfo><title>Journal of the American Oil Chemists’ Society</title>
</titleInfo>
<titleInfo type="abbreviated"><title>J Am Oil Chem Soc</title>
</titleInfo>
<genre type="journal" displayLabel="Archive Journal" authority="ISTEX" valueURI="https://publication-type.data.istex.fr/ark:/67375/JMC-0GLKJH51-B">journal</genre>
<originInfo><publisher>Springer</publisher>
<dateIssued encoding="w3cdtf">1995-12-01</dateIssued>
<copyrightDate encoding="w3cdtf">1995</copyrightDate>
</originInfo>
<subject><genre>Chemistry</genre>
<topic>Chemistry/Food Science, general</topic>
<topic>Analytical Chemistry</topic>
<topic>Biotechnology</topic>
<topic>Industrial Chemistry/Chemical Engineering</topic>
<topic>Biomaterials</topic>
<topic>Agriculture</topic>
</subject>
<identifier type="ISSN">0003-021X</identifier>
<identifier type="eISSN">1558-9331</identifier>
<identifier type="JournalID">11746</identifier>
<identifier type="IssueArticleCount">34</identifier>
<identifier type="VolumeIssueCount">12</identifier>
<part><date>1995</date>
<detail type="volume"><number>72</number>
<caption>vol.</caption>
</detail>
<detail type="issue"><number>12</number>
<caption>no.</caption>
</detail>
<extent unit="pages"><start>1471</start>
<end>1483</end>
</extent>
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<recordInfo><recordOrigin>AOCS Press, 1995</recordOrigin>
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<identifier type="ark">ark:/67375/1BB-26VZJ2RP-7</identifier>
<identifier type="DOI">10.1007/BF02577840</identifier>
<identifier type="ArticleID">BF02577840</identifier>
<identifier type="ArticleID">Art12</identifier>
<accessCondition type="use and reproduction" contentType="copyright">AOCS Press, 1995</accessCondition>
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