<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html> <head> <title>UTas ePrints - The impact of different wort boiling temperatures on the beer foam stabilizing properties of lipid transfer protein 1</title> <script type="text/javascript" src="http://eprints.utas.edu.au/javascript/auto.js"><!-- padder --></script> <style type="text/css" media="screen">@import url(http://eprints.utas.edu.au/style/auto.css);</style> <style type="text/css" media="print">@import url(http://eprints.utas.edu.au/style/print.css);</style> <link rel="icon" href="/images/eprints/favicon.ico" type="image/x-icon" /> <link rel="shortcut icon" href="/images/eprints/favicon.ico" type="image/x-icon" /> <link rel="Top" href="http://eprints.utas.edu.au/" /> <link rel="Search" href="http://eprints.utas.edu.au/cgi/search" /> <meta content="van Nierop, S.N.E." name="eprints.creators_name" /> <meta content="Evans, D.E" name="eprints.creators_name" /> <meta content="Axcell, B.C." name="eprints.creators_name" /> <meta content="Cantrell, I.C." name="eprints.creators_name" /> <meta content="Rautenbach, M." name="eprints.creators_name" /> <meta content="" name="eprints.creators_id" /> <meta content="Daniel.Evans@utas.edu.au" name="eprints.creators_id" /> <meta content="" name="eprints.creators_id" /> <meta content="" name="eprints.creators_id" /> <meta content="" name="eprints.creators_id" /> <meta content="article" name="eprints.type" /> <meta content="2007-10-24 01:00:57" name="eprints.datestamp" /> <meta content="2008-01-08 15:30:00" name="eprints.lastmod" /> <meta content="show" name="eprints.metadata_visibility" /> <meta content="The impact of different wort boiling temperatures on the beer foam stabilizing properties of lipid transfer protein 1" name="eprints.title" /> <meta content="pub" name="eprints.ispublished" /> <meta content="300000" name="eprints.subjects" /> <meta content="restricted" name="eprints.full_text_status" /> <meta content="Brewing; wort boiling; beer; foam quality; lipid transfer protein" name="eprints.keywords" /> <meta content="Beer consumers demand satisfactory and consistent foam stability; thus, it is a high priority for brewers. Beer foam is stabilized by the interaction between certain beer proteins, including lipid transfer protein 1 (LTP1), and isomerized hop R-acids, but destabilized by lipids. In this study it was shown that the wort boiling temperature during the brewing process was critical in determining the final beer LTP1 content and conformation. LTP1 levels during brewing were measured by an LTP1 ELISA, using antinative barley LTP1 polyclonal antibodies. It was observed that the higher wort boiling temperatures (102 °C), resulting from low altitude at sea level, reduced the final beer LTP1 level to 2-3 íg/mL, whereas the lower wort boiling temperatures (96 °C), resulting from higher altitudes (1800 m), produced LTP1 levels between 17 and 35 íg/mL. Low levels of LTP1 in combination with elevated levels of free fatty acids (FFA) resulted in poor foam stability, whereas beer produced with low levels of LTP1 and FFA had satisfactory foam stability. Previous studies indicated the need for LTP1 denaturing to improve its foam stabilizing properties. However, the results presented here show that LTP1 denaturation reduces its ability to act as a binding protein for foam-damaging FFA. These investigations suggest that wort boiling temperature is an important factor in determining the level and conformation of LTP1, thereby favoring satisfactory beer foam stability." name="eprints.abstract" /> <meta content="2004" name="eprints.date" /> <meta content="published" name="eprints.date_type" /> <meta content="Journal of Agricultural and Food Chemistry" name="eprints.publication" /> <meta content="52" name="eprints.volume" /> <meta content="3120-3129" name="eprints.pagerange" /> <meta content="10.1021/jf035125c" name="eprints.id_number" /> <meta content="TRUE" name="eprints.refereed" /> <meta content="0021-8561" name="eprints.issn" /> <meta content="http://dx.doi.org/10.1021/jf035125c" name="eprints.official_url" /> <meta content="(1) Bamforth, C. W. Perceptions of beer foam. J. Inst. Brew. 2000, 106, 229-238. (2) Ono, M.; Hashimoto, S.; Kakudo, Y.; Nagami, K.; Kumada, J. Foaming and beer flavor. J. Am. Soc. Brew. Chem. 1983, 41, 19-23. (3) Lewis, M. J.; Young, T. W. Brewing; Aspen Publishers: Gaithersberg, MD, 2001. (4) Evans, D. E.; Sheehan, M. C. Do not be fobbed off, the substance of beer foam, a review. J. Am. Soc. Brew. Chem. 2002, 60, 47- 57. (5) Hejgaard, J. Origin of dominant beer protein immunochemical identity with â-amylase-associated protein from barley. J. Inst. Brew. 1977, 83, 94-96. (6) Jones, B. L.; Marinac, L. A. Barley LTP1 (PAP1) and LTP2 are inhibitors of green malt cysteine endoproteinases. J. Am. Soc. Brew. Chem. 1995, 53, 194-195. (7) Kaersgaard, P.; Hejgaard, J. Antigenic beer macromolecules, an experimental survey of purification methods. J. Inst. Brew. 1979, 85, 103-111. (8) Bech, L. M.; Vaag, P.; Heinemann, B.; Breddam, K. Throughout the brewing process barley lipid transfer protein 1 (LTP1) is transformed into a more foam-promoting form. Eur. Brew. ConV. Congr. Proc., Brussels 1995, 25, 561-568. (9) Lusk, L. T.; Goldstein, H.; Ryder, D. Independent role of beer proteins, melanoidins and polysaccharides in foam formation. J. Am. Soc. Brew. Chem. 1995, 53, 93-103. (10) Sorensen, S. B.; Bech, L. M.; Muldberg, M.; Beenfeldt, T.; Breddam, K. Barley lipid transfer protein 1 is involved in beer foam formation. Master Brew. Assoc. Am. Tech. Q. 1993, 30, 135-145. (11) Narziss, L. Modern wort boiling. Proc. Inst. Brew. ConV., Somerset West, S. Afr. 1993, 195-212. (12) Dickie, K. H.; Cann, C.; Norman, E. C.; Bamforth, C. W.; Muller, R. E. Foam negative materials. J. Am. Soc. Brew. Chem. 2001, 59, 17-23. (13) Roberts, R. T.; Keeney, P. J.; Wainwright, T. The effects of lipids and related materials on beer foam. J. Inst. Brew. 1978, 84, 9-12. (14) Ronteltap, A. D.; Hollemans, M.; Bisperink, C. G. J.; Prims, A. Beer foam physics. Master Brew. Assoc. Am. Tech. Q. 1991, 28, 25-32. (15) Gromus, J. Negative influences on foam. Eur. Brew. ConV. Monograph 1998, No. 27, 69-83. (16) Bamforth, C. W. The foaming properties of beer. J. Inst. Brew. 1985, 91, 370-383. (17) Glenister, P. R.; Segal, E. Foam evaluation: I. primary cling; secondary cling; foam strength. Proc. Am. Soc. Brew. Chem. 1964, 55-63. (18) Clarke, D. C.; Wilde, P. J.; Marion, D. The protection of beer foam against lipid-induced destabilization. J. Inst. Brew. 1994, 100, 23-25. (19) Morris, K. S.; Hough, J. S. Lipid-protein interactions in beer and beer foam brewed with wheat flour. J. Am. Soc. Brew. Chem. 1987, 45, 43-47. (20) Onishi, A.; Canterranne, E.; Clarke, D. J.; Proudlove, M. O. Barley lipid binding proteins: their role in beer stabilization. Eur. Brew. ConV. Congr. Proc., Brussels 1995, 25, 553-560. (21) Kader, J. C. Lipid transfer proteins in plants. Annu. ReV. Plant Physiol. Plant Mol. Biol. 1996, 47, 627-654. (22) Evans, D. E.; Hejgaard, J. The impact of malt derived proteins on beer foam quality. Part I. The effect of germination and kilning on the level of protein Z4, protein Z7 and LTP1. J. Inst. Brew. 1999, 105, 159-169. (23) Lusk, L. T.; Goldstein, H.; Watts, K.; Navarro, A.; Ryder, D. Monitoring barley lipid transfer protein levels in barley, malting and brewing. Eur. Brew. ConV. Congr. Proc., Budapest 2001, 28, 663-672. (24) Klopper, W. J. Measurement of foam stability. Brew. Dig. 1977, 52, 51-53. (25) Venter, P.; Kock, J. L. F.; Kuwa, S.; Botha, A.; Coetzee, D. J.; Botes, P. J.; Bhatt, R. K.; Schewe, T.; Nigram, S. Production of 3R-hydroxy-polyenoic fatty acids by the yeast Dipodascopsis uninucleata. Lipids 1997, 32, 1277-1283. (26) Laemmli, U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 1970, 227, 680-685. (27) Lide, D. R. Handbook of Chemistry and Physics, 71st ed.; CPD Press: Boston, MA, 1990. (28) Narziss, L.; Miedaner, H.; Scheider, S. Some aspects of the technology of wort boiling today. Brauwelt Int. 1992, 4, 346- 355. (29) Willaert, R. G.; Baron, G. V. Wort boiling today- boiling systems with low thermal stress in combination with volatile stripping. J. Brew. Biotechnol. 2001, 26, 217-230. (30) Jegou, S.; Douliez, J.-P.; Molle, D.; Boivin, P.; Marion, D. Evidence of the glycation and denaturation of LTP1 during the malting and brewing process. J. Agric. Food Chem. 2001, 49, 4942-4949. (31) Jegou, S.; Douliez, J.-P.; Molle, D.; Boivin, P.; Marion, D. Purification and characterization of LTP polypeptide from beer. J. Agric. Food Chem. 2000, 48, 5023-5029. (32) Lindorff-Larsen, K.; Lerche, M. H.; Poulsen, F. M.; Roepsstoff, P.; Winther, J. R. Barley lipid transfer protein, LTP1, contains a new type of lipid-like post-transcriptional modification. J. Biol. Chem. 2001, 276, 33547-33553. (33) Slack, P. T.; Bamforth, C. W. The fractionation of polypeptides from barley and beer by hydrophobic interaction chromatography: the influence of their hydrophobicity on foam stability. J. Inst. Brew. 1983, 89, 397-401. (34) Chowdhury, S. K.; Katta, V.; Chait, B. T. Probing conformational changes in proteins by mass spectrometry. J. Am. Chem. Soc. 1990, 112, 9012-9013. (35) Grandori, R. Detecting equilibrium cytochrome c folding intermediates by electrospray ionization mass spectrometry: two partially folded forms populate the molten-globule state. Protein Sci. 2002, 11, 453-458. (36) Gumerov, D. R.; Dobo, A.; Kaltashov, I. A. Protein-ion chargestate distributions in electrospray ionization mass spectrometry: 3128 J. Agric. Food Chem., Vol. 52, No. 10, 2004 Van Nierop et al. distinguishing conformational contributions from masking effects. Eur. J. Mass Spectrom. 2002, 8, 123-125. (37) Simmons, D. A.; Konermann, L. Characterization of transient protein folding intermediates during myoglobin reconstitution by time-resolved electrospray mass spectrometry with on-line isotopic pulse labeling. Biochemistry 2002, 41, 1906-1914. (38) Winston, R. L.; Fitzgerald, M. C. Mass spectrometry as a readout of protein structure and function. Mass Spectrom. ReV. 1997, 16, 165-179. (39) Heinemann, B.; Andersen, K. V.; Nielsen, P. R.; Bech, L. M.; Poulsen, F. M. Structure in solution of a four-helix lipid binding protein. Protein Sci. 1996, 5, 13-23. R" name="eprints.referencetext" /> <meta content="van Nierop, S.N.E. and Evans, D.E and Axcell, B.C. and Cantrell, I.C. and Rautenbach, M. (2004) The impact of different wort boiling temperatures on the beer foam stabilizing properties of lipid transfer protein 1. Journal of Agricultural and Food Chemistry, 52 . pp. 3120-3129. ISSN 0021-8561" name="eprints.citation" /> <meta content="http://eprints.utas.edu.au/2315/1/_vanNierop_JAFC-04.pdf" name="eprints.document_url" /> <link rel="schema.DC" href="http://purl.org/DC/elements/1.0/" /> <meta content="The impact of different wort boiling temperatures on the beer foam stabilizing properties of lipid transfer protein 1" name="DC.title" /> <meta content="van Nierop, S.N.E." name="DC.creator" /> <meta content="Evans, D.E" name="DC.creator" /> <meta content="Axcell, B.C." name="DC.creator" /> <meta content="Cantrell, I.C." name="DC.creator" /> <meta content="Rautenbach, M." name="DC.creator" /> <meta content="300000 Agricultural, Veterinary and Environmental Sciences" name="DC.subject" /> <meta content="Beer consumers demand satisfactory and consistent foam stability; thus, it is a high priority for brewers. Beer foam is stabilized by the interaction between certain beer proteins, including lipid transfer protein 1 (LTP1), and isomerized hop R-acids, but destabilized by lipids. In this study it was shown that the wort boiling temperature during the brewing process was critical in determining the final beer LTP1 content and conformation. LTP1 levels during brewing were measured by an LTP1 ELISA, using antinative barley LTP1 polyclonal antibodies. It was observed that the higher wort boiling temperatures (102 °C), resulting from low altitude at sea level, reduced the final beer LTP1 level to 2-3 íg/mL, whereas the lower wort boiling temperatures (96 °C), resulting from higher altitudes (1800 m), produced LTP1 levels between 17 and 35 íg/mL. Low levels of LTP1 in combination with elevated levels of free fatty acids (FFA) resulted in poor foam stability, whereas beer produced with low levels of LTP1 and FFA had satisfactory foam stability. Previous studies indicated the need for LTP1 denaturing to improve its foam stabilizing properties. However, the results presented here show that LTP1 denaturation reduces its ability to act as a binding protein for foam-damaging FFA. These investigations suggest that wort boiling temperature is an important factor in determining the level and conformation of LTP1, thereby favoring satisfactory beer foam stability." name="DC.description" /> <meta content="2004" name="DC.date" /> <meta content="Article" name="DC.type" /> <meta content="PeerReviewed" name="DC.type" /> <meta content="application/pdf" name="DC.format" /> <meta content="http://eprints.utas.edu.au/2315/1/_vanNierop_JAFC-04.pdf" name="DC.identifier" /> <meta content="http://dx.doi.org/10.1021/jf035125c" name="DC.relation" /> <meta content="van Nierop, S.N.E. and Evans, D.E and Axcell, B.C. and Cantrell, I.C. and Rautenbach, M. (2004) The impact of different wort boiling temperatures on the beer foam stabilizing properties of lipid transfer protein 1. Journal of Agricultural and Food Chemistry, 52 . pp. 3120-3129. 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border: solid 1px #ccc; padding: 3px"><tr> <td align="left"><a href="http://eprints.utas.edu.au/cgi/users/home">Login</a> | <a href="http://eprints.utas.edu.au/cgi/register">Create Account</a></td> <td align="right" style="white-space: nowrap"> <form method="get" accept-charset="utf-8" action="http://eprints.utas.edu.au/cgi/search" style="display:inline"> <input class="ep_tm_searchbarbox" size="20" type="text" name="q" /> <input class="ep_tm_searchbarbutton" value="Search" type="submit" name="_action_search" /> <input type="hidden" name="_order" value="bytitle" /> <input type="hidden" name="basic_srchtype" value="ALL" /> <input type="hidden" name="_satisfyall" value="ALL" /> </form> </td> </tr></table></td></tr> <tr> <td class="toplinks"><!-- InstanceBeginEditable name="content" --> <div align="center"> <table width="720" class="ep_tm_main"><tr><td align="left"> <h1 class="ep_tm_pagetitle">The impact of different wort boiling temperatures on the beer foam stabilizing properties of lipid transfer protein 1</h1> <p style="margin-bottom: 1em" class="not_ep_block"><span class="person_name">van Nierop, S.N.E.</span> and <span class="person_name">Evans, D.E</span> and <span class="person_name">Axcell, B.C.</span> and <span class="person_name">Cantrell, I.C.</span> and <span class="person_name">Rautenbach, M.</span> (2004) <xhtml:em>The impact of different wort boiling temperatures on the beer foam stabilizing properties of lipid transfer protein 1.</xhtml:em> Journal of Agricultural and Food Chemistry, 52 . pp. 3120-3129. ISSN 0021-8561</p><p style="margin-bottom: 1em" class="not_ep_block"></p><table style="margin-bottom: 1em" class="not_ep_block"><tr><td valign="top" style="text-align:center"><a href="http://eprints.utas.edu.au/2315/1/_vanNierop_JAFC-04.pdf"><img alt="[img]" src="http://eprints.utas.edu.au/style/images/fileicons/application_pdf.png" class="ep_doc_icon" border="0" /></a></td><td valign="top"><a href="http://eprints.utas.edu.au/2315/1/_vanNierop_JAFC-04.pdf"><span class="ep_document_citation">PDF</span></a> - Full text restricted - Requires a PDF viewer<br />187Kb</td><td><form method="get" accept-charset="utf-8" action="http://eprints.utas.edu.au/cgi/request_doc"><input accept-charset="utf-8" value="2965" name="docid" type="hidden" /><div class=""><input value="Request a copy" name="_action_null" class="ep_form_action_button" onclick="return EPJS_button_pushed( '_action_null' )" type="submit" /> </div></form></td></tr></table><p style="margin-bottom: 1em" class="not_ep_block">Official URL: <a href="http://dx.doi.org/10.1021/jf035125c">http://dx.doi.org/10.1021/jf035125c</a></p><div class="not_ep_block"><h2>Abstract</h2><p style="padding-bottom: 16px; text-align: left; margin: 1em auto 0em auto">Beer consumers demand satisfactory and consistent foam stability; thus, it is a high priority for brewers. Beer foam is stabilized by the interaction between certain beer proteins, including lipid transfer protein 1 (LTP1), and isomerized hop R-acids, but destabilized by lipids. In this study it was shown that the wort boiling temperature during the brewing process was critical in determining the final beer LTP1 content and conformation. LTP1 levels during brewing were measured by an LTP1 ELISA, using antinative barley LTP1 polyclonal antibodies. It was observed that the higher wort boiling temperatures (102 °C), resulting from low altitude at sea level, reduced the final beer LTP1 level to 2-3 íg/mL, whereas the lower wort boiling temperatures (96 °C), resulting from higher altitudes (1800 m), produced LTP1 levels between 17 and 35 íg/mL. Low levels of LTP1 in combination with elevated levels of free fatty acids (FFA) resulted in poor foam stability, whereas beer produced with low levels of LTP1 and FFA had satisfactory foam stability. Previous studies indicated the need for LTP1 denaturing to improve its foam stabilizing properties. However, the results presented here show that LTP1 denaturation reduces its ability to act as a binding protein for foam-damaging FFA. These investigations suggest that wort boiling temperature is an important factor in determining the level and conformation of LTP1, thereby favoring satisfactory beer foam stability.</p></div><table style="margin-bottom: 1em" cellpadding="3" class="not_ep_block" border="0"><tr><th valign="top" class="ep_row">Item Type:</th><td valign="top" class="ep_row">Article</td></tr><tr><th valign="top" class="ep_row">Keywords:</th><td valign="top" class="ep_row">Brewing; wort boiling; beer; foam quality; lipid transfer protein</td></tr><tr><th valign="top" class="ep_row">Subjects:</th><td valign="top" class="ep_row"><a href="http://eprints.utas.edu.au/view/subjects/300000.html">300000 Agricultural, Veterinary and Environmental Sciences</a></td></tr><tr><th valign="top" class="ep_row">ID Code:</th><td valign="top" class="ep_row">2315</td></tr><tr><th valign="top" class="ep_row">Deposited By:</th><td valign="top" class="ep_row"><span class="ep_name_citation"><span class="person_name">Dr Evan Evans</span></span></td></tr><tr><th valign="top" class="ep_row">Deposited On:</th><td valign="top" class="ep_row">24 Oct 2007 12:00</td></tr><tr><th valign="top" class="ep_row">Last Modified:</th><td valign="top" class="ep_row">09 Jan 2008 02:30</td></tr><tr><th valign="top" class="ep_row">ePrint Statistics:</th><td valign="top" class="ep_row"><a target="ePrintStats" href="/es/index.php?action=show_detail_eprint;id=2315;">View statistics for this ePrint</a></td></tr></table><p align="right">Repository Staff Only: <a href="http://eprints.utas.edu.au/cgi/users/home?screen=EPrint::View&eprintid=2315">item control page</a></p> </td></tr></table> </div> <!-- InstanceEndEditable --></td> </tr> <tr> <td><!-- #BeginLibraryItem "/Library/footer_eprints.lbi" --> <table width="795" border="0" align="left" cellpadding="0" class="footer"> <tr valign="top"> <td colspan="2"><div align="center"><a href="http://www.utas.edu.au">UTAS home</a> | <a href="http://www.utas.edu.au/library/">Library home</a> | <a href="/">ePrints home</a> | <a href="/contact.html">contact</a> | <a href="/information.html">about</a> | <a href="/view/">browse</a> | <a href="/perl/search/simple">search</a> | <a href="/perl/register">register</a> | <a href="/perl/users/home">user area</a> | <a href="/help/">help</a></div><br /></td> </tr> <tr><td colspan="2"><p><img src="/images/eprints/footerline.gif" width="100%" height="4" /></p></td></tr> <tr valign="top"> <td width="68%" class="footer">Authorised by the University Librarian<br /> © University of Tasmania ABN 30 764 374 782<br /> <a href="http://www.utas.edu.au/cricos/">CRICOS Provider Code 00586B</a> | <a href="http://www.utas.edu.au/copyright/copyright_disclaimers.html">Copyright & Disclaimers</a> | <a href="http://www.utas.edu.au/accessibility/index.html">Accessibility</a> | <a href="http://eprints.utas.edu.au/feedback/">Site Feedback</a> </td> <td width="32%"><div align="right"> <p align="right" class="NoPrint"><a href="http://www.utas.edu.au/"><img src="http://www.utas.edu.au/shared/logos/unioftasstrip.gif" alt="University of Tasmania Home Page" width="260" height="16" border="0" align="right" /></a></p> <p align="right" class="NoPrint"><a href="http://www.utas.edu.au/"><br /> </a></p> </div></td> </tr> <tr valign="top"> <td><p> </p></td> <td><div align="right"><span class="NoPrint"><a href="http://www.eprints.org/software/"><img src="/images/eprintslogo.gif" alt="ePrints logo" width="77" height="29" border="0" align="bottom" /></a></span></div></td> </tr> </table> <!-- #EndLibraryItem --> <div align="center"></div></td> </tr> </table> </body> </html>