Re: conservation of albumen
Yes, I noticed that -> will wait at least 10 days if I ever get into albumen in the future. Regards, Loris. 19 Ocak 2009, Pazartesi, 11:51 am tarihinde, Alberto Novo yazmış: > I would remark (see my previous stanford.edu citation) that a week only at > room temperature may not be enough for the complete destruction of albumen > glucose: > "Fresh egg white was beaten in a household blender for 1-1 / 2 minutes on > high speed, allowed to settle back to liquid form, then incubated in > loosely > covered containers at 30°C. Fermentation of egg white in this manner was > described in an article by Stuart and Goresline and in several places in > the > 19th-century literature on albumen paper manufacturing. Unless speeded up > by > inoculation with appropriate bacteria, the process takes about 10 days". > "The pH of the albumen falls during the process from approximately 9.0 to > 6.0-6.5 [at] completion". > "After 6 days the pH was 8.5"... "After 10 days, the albumen tested > negative > for glucose and the pH was 6.42". > > Alberto > > >> >>> I always thought that yellowing is the function of sensitizing / >>> incomplete fixing and non ideal storage conditions... You say that non >>> sensitized paper also will yellow with time? >> >> See http://albumen.stanford.edu/library/c20/reilly1982a.html >> The non-smelling brands of albumen paper were those which developed >> yellowing in the highlights (also in the shadows, but the effect was >> overwhelmed by the silver layer) more than smelling (albumen aged before >> coating) papers. >> The Maillard reaction has recently been revised also in cooking. It is >> the >> responsible of the brown and tasty crust of the bread, of the outer part >> of a grilled steak, and so on. It is fast at high temperature, but with >> times long enough it works also at room temperature. >> >> Alberto
|