From owner-metabolic-reg@net.bio.net Wed Jan 29 22:00:00 1997 Path: biosci!rutgers!news.sgi.com!howland.erols.net!ix.netcom.com!news From: "\"Uncle Al\" Schwartz" Newsgroups: bionet.metabolic-reg,sci.chem,sci.life-extension,sci.med,sci.med.pharmacy,sci.med.nutrition,rec.crafts.brewing,rec.crafts.winemaking Subject: Re: A-level help needed! - Chemistry & fermentation Date: Thu, 30 Jan 1997 08:41:07 -0800 Organization: The Noble Krell Lines: 27 Message-ID: <32F0CF22.3EC5@ix.netcom.com> References: <854622079.25760@dejanews.com> Reply-To: UncleAl0@ix.netcom.com NNTP-Posting-Host: irv-ca19-01.ix.netcom.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-NETCOM-Date: Thu Jan 30 8:34:27 AM PST 1997 X-Mailer: Mozilla 3.0 (Win16; U) To: richards_@msn.com Xref: biosci bionet.metabolic-reg:969 sci.chem:73986 sci.life-extension:16554 sci.med:149174 sci.med.pharmacy:40476 sci.med.nutrition:58476 rec.crafts.brewing:106924 rec.crafts.winemaking:15344 parkstone@lds.co.uk wrote: > > Hi, I'm an A-level student currently studying chemistry. I am presently > involved in an extended investigation, which makes up part of my final > grade, on the comparison of the rate of fermentation with use of different > sugar substrates. Below is my outline proposal . . . . > > During alcoholic fermentation, yeast metabolises glucose to form ethanol > and carbon dioxide using a metabolic pathway consisting of a number of > enzymes. By making the assumption that the yeast cell is a single > catalytic reactant, glucose (as a control), mannose, galactose and > fructose will be added separately to yeast solution. [snip] You had best be explicit about temperature control. Bulk fermentations get hot; small scale fermentations must be thermostated. Not only will base metabolic rate depend upon temperature, but water saturation of offgas plus PV=nRT will alter your measurements. -- Alan "Uncle Al" Schwartz UncleAl0@ix.netcom.com ("zero" before @) http://www.ultra.net.au/~wisby/uncleal.htm (Toxic URL! Unsafe for children, Democrats, and most mammals) "Quis custodiet ipsos custodes?" The Net! .