EccentricDyslexic
Active Member
Hi all,
Been waiting for 2 days to post this on Jims, but cant wait anylonger so will post here, hopefuly you guys are as nice as the chaps on Jims(I'm sure yous are :thumb: !
Have been trying to get my head round propagating yeast from a slope, there is info scattered all over the forums and net so am trying to bring this all together in one place so I and others can have a one stop place for all the info we need. I have from my research come up with the following procedure, but i still have questions, can you knowledgeable chaps advise on the suggested procedure?
<start>
Procedure-
1- Gather your stuff- yeast slope, a sterilised 200ml bottle, 5x2 litre sterilised bottles, wort, blow torch or lighter, sterile 20ml syringe, sterile gloves, two demijohns bungs and airlocks
2- Make up 100ml of sterile wort at about 1040SG by mixing DME(dry malt extract) with water and boil it for 15minutes, allow to cool to 25c
3- Suck up 10ml wort into the sterile syringe
4- Squirt the 10ml of wort into the slope
5- shake the slope vigorously for a minute
6- half fill the 200ml bottle with wort (its important to leave half the bottle with air in it for oxygenation of the wort to promote propagation of the yeast)
7- pour the wort from the slope into the 200ml bottle
8- shake the bottle to oxygenate the wort/yeast mix
9- loosen the lid of the bottle a little
10- keep the solution at about 20c for 24-48 hours
11- when the solutionâs activity has settled, make up a litre of boiled wort as above
12- allow the 1liter of wort to cool to 25c
13- put the 1litre of wort into the sterile 2litre bottle
14- add the propagated 100ml wort/yeast solution to the 2 litre bottle
15- shake the bottle to oxygenate the wort/yeast mix
16- loosen the lid of the bottle a little
17- keep the solution at about 20c for 24-48 hours
18- when the solutionâs activity has settled, make up 4 litres of boiled wort as above
19- allow the 4 litres of wort to cool to 25c
20- split the 4 litres of wort into 2 sterile demijohns
21- shake and split the propagated 1litre wort/yeast solution between the two demijohns
22- shake the demijohns to oxygenate the wort/yeast mix
23- fit air locks to the demijohns
24- keep the solutions at about 20c for 24-48 hours
25- when the solutionâs activity has settled, swirl the mixture to re-suspend the yeast in the wort
26- siphon the mixture(being careful not to splash or oxygenate the solution) into five one litre bottles (fill to about an inch lower than the rim)
27- squeeze the bottle sides to displace any air from the bottles and refit the lid tightly
28- put your 5 starters in the fridge! (check the bottles regularly for a few hours to make sure activity has stopped and the bottles remain squeezed or soft and not hard and about to explode!)
Notes-
Wash your hands and wear sterile gloves. Whenever you remove or replace a bottle or slope lid, flame both parts by passing them through a gentle flame briefly, this helps prevent bacterial and fungal contamination. Donât leave sterile bottles with lids off. Keep the working area as clean as possible, draft free and donât breathe on any open slopes or bottles! Wearing a disposable mask is a good idea. <end>
Am I right in thinking that we donât want to leave the propagating solution at room temps after the initial aerobic activity has completed at each stage? Otherwise the yeast will start fermenting rather than multiplying in the anaerobic solution? Is it possible to differentiate between propagation and fermentation visually?
Another question, some books refer to using âhopped wortâ- is this essential? if so, how much hop would you recommend boiling with the dme/water mix?...or are there other suggestions on how to make hopped wort?
In anticipation of many useful suggestions, thanks for all your continuing help chaps!
Steve
Been waiting for 2 days to post this on Jims, but cant wait anylonger so will post here, hopefuly you guys are as nice as the chaps on Jims(I'm sure yous are :thumb: !
Have been trying to get my head round propagating yeast from a slope, there is info scattered all over the forums and net so am trying to bring this all together in one place so I and others can have a one stop place for all the info we need. I have from my research come up with the following procedure, but i still have questions, can you knowledgeable chaps advise on the suggested procedure?
<start>
Procedure-
1- Gather your stuff- yeast slope, a sterilised 200ml bottle, 5x2 litre sterilised bottles, wort, blow torch or lighter, sterile 20ml syringe, sterile gloves, two demijohns bungs and airlocks
2- Make up 100ml of sterile wort at about 1040SG by mixing DME(dry malt extract) with water and boil it for 15minutes, allow to cool to 25c
3- Suck up 10ml wort into the sterile syringe
4- Squirt the 10ml of wort into the slope
5- shake the slope vigorously for a minute
6- half fill the 200ml bottle with wort (its important to leave half the bottle with air in it for oxygenation of the wort to promote propagation of the yeast)
7- pour the wort from the slope into the 200ml bottle
8- shake the bottle to oxygenate the wort/yeast mix
9- loosen the lid of the bottle a little
10- keep the solution at about 20c for 24-48 hours
11- when the solutionâs activity has settled, make up a litre of boiled wort as above
12- allow the 1liter of wort to cool to 25c
13- put the 1litre of wort into the sterile 2litre bottle
14- add the propagated 100ml wort/yeast solution to the 2 litre bottle
15- shake the bottle to oxygenate the wort/yeast mix
16- loosen the lid of the bottle a little
17- keep the solution at about 20c for 24-48 hours
18- when the solutionâs activity has settled, make up 4 litres of boiled wort as above
19- allow the 4 litres of wort to cool to 25c
20- split the 4 litres of wort into 2 sterile demijohns
21- shake and split the propagated 1litre wort/yeast solution between the two demijohns
22- shake the demijohns to oxygenate the wort/yeast mix
23- fit air locks to the demijohns
24- keep the solutions at about 20c for 24-48 hours
25- when the solutionâs activity has settled, swirl the mixture to re-suspend the yeast in the wort
26- siphon the mixture(being careful not to splash or oxygenate the solution) into five one litre bottles (fill to about an inch lower than the rim)
27- squeeze the bottle sides to displace any air from the bottles and refit the lid tightly
28- put your 5 starters in the fridge! (check the bottles regularly for a few hours to make sure activity has stopped and the bottles remain squeezed or soft and not hard and about to explode!)
Notes-
Wash your hands and wear sterile gloves. Whenever you remove or replace a bottle or slope lid, flame both parts by passing them through a gentle flame briefly, this helps prevent bacterial and fungal contamination. Donât leave sterile bottles with lids off. Keep the working area as clean as possible, draft free and donât breathe on any open slopes or bottles! Wearing a disposable mask is a good idea. <end>
Am I right in thinking that we donât want to leave the propagating solution at room temps after the initial aerobic activity has completed at each stage? Otherwise the yeast will start fermenting rather than multiplying in the anaerobic solution? Is it possible to differentiate between propagation and fermentation visually?
Another question, some books refer to using âhopped wortâ- is this essential? if so, how much hop would you recommend boiling with the dme/water mix?...or are there other suggestions on how to make hopped wort?
In anticipation of many useful suggestions, thanks for all your continuing help chaps!
Steve