On 22 Mar 1996 11:41:28 -0800, usmbcfm3 at IBMMAIL.COM wrote:
>>We are looking for a good, accurate, relatively fast and simple method to
>measure yeast quality (i. e., viability and vitality) with respect to the t
>yeas's ability to ferment.
>>We are currently looking at measuring CO2 evolution on different sugars, but
>are concerned with how to measure CO2 production and how to quantitate such
>measurements with repect to the yeast. For example, do we add yeast by number,
>mass, or volume? Should we have excess sugar with respect to the yeast and
>measure initial rate of CO2 production or have excess yeast and measure time to
>end ferment the sugar?
>>Does anyone have a method and/or know of an instrument to do this?
>>Any advice will be greatly appreciated. Thanks.
If you are looking for a simple relative method...you establish the
parameters from your "ideal" yeast...I might suggest using
yeast nitrogen base with 10 gm/l dextrose and BCP..this will give
you a visual monitor...color change from purple to yellow, dependent
on acid/CO2 production....establish a growth activity color chart...or
actually measure pH at specific incubation time and temperature.
This system works well if you establish and adhere to methods, so that
your measurements are comparable. Set cell density to MacFarland #1.
Robert Randolph Randolph Biomedical
21 McElroy Street West Warwick, RI 02893
401-826-1407 rand777 at ids.nethttp://www2.ids.net/~rand777/home.htm