Thursday 28 March 2013

Secondary Fermentation

If I have any interested friends left in 'blogland' it will be a miracle! However, in the remote chance anyone is still looking in, I'm about to bore you to tears with this the next stage in the great sap wine project. One quick check with the hydrometer shows the gravity reading has now reached 1.010. If you scroll down to my previous two posts, you can compare this against my initial reading of 1.090 (posted just a week ago). As the eventual aim is for 0.990, you can see that about 80% of the sugar has already been converted to alcohol and CO2 by the yeast. However, converting the final 20% could take several months. As the alcohol content increases, the speed at which the yeast can work gets much slower. During the vigorous Primary Fermentation, the yeast is multiplying to fill the volume of the liquid. The yeast needs plenty of oxygen at this stage, so it is often a good idea (as here) to start the wine off in a brewing bucket and stir it several time a day. But now the process is slowing I need to do the opposite and prevent the air from reaching the wine to keep out any spoilage bacteria. This stage is called the Secondary Fermentation and takes place in a demijohn with an airlock fitted in the bung at the top.
Someone once said that the art of good wine making is to spend 70% of your time sterilising everything.
Here is some of the equipment I need after I have sterilised it (including the table top).
Once everything is sterilised I can start to strain the liquid through a muslin before putting it into my demijohn.
Karen let me use her cheese strainer to leave the remaining solids (of orange, lemon and rasins) to drip and eke out as much flavour as possible :-)
Here is the result - I had to improvise with a 4 pint milk carton to take the overflow. Hopefully this will eventually yield 7 or 8 bottles.
Actually, all this wine making in the shed was cheering me up because I've been going down with a rather heavy cold. Karen also decided very sweetly, to help me to feel better by buying me this bag!

24 comments:

  1. Jerry...I'm still amazed at the whole "birch sap" part and being able to make wine out of it.

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    1. Jude, thanks for still being interested! To be honest the sap doesn't have much flavour of its own; its main purpose seems to be to provide all the liquid content but it is reckoned to be a good tonic.

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  2. Still here, still following.....and actually enjoy seeing this process. Hope the man flu isn't too bad!

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    1. Thanks Ann, actually, this morning the man flu is making me feel a bit grumpy :(

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  3. Fascinating again Jerry :) Oh how I remember the sterilising - seemed to take longer than making the wine :)

    Hope you feel better soon.

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    1. Yes, you are so right. Sometimes I feel rather impatient with all the cleaning and sterilising and want to get on with all the fun stuff!

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  4. Hi Jerry!
    Interesting as allways!
    /Ingemar

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  5. Well, if attention to detail is anything to go by Jerry you should have something quite special at the end of it all! Although the mention of tonic is slightly worrying, I do hope it's not going to taste like medicine ;-)

    Hope you are feeling better....otherwise you may wish you'd made your 'tonic' earlier ;-)

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    1. Jan, I can't promise that it wont taste like medicine. Thanks for your well-wishes, I'm supposed to be singing this evening but my throat is rather sore - I expect I'll get through though.

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  6. Hi Jerry! I'm following the whole process with interest and anticipation! I wish I could taste it when it's ready. Happy Easter to you and your family too!

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    1. Thanks Judy, hopefully it will be worth the wait!

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  7. A job really complicated! I admire your perseverance and I hope that the wine birch not has the flavor of a medicine, but it will ALSO VERY good to drink.
    After a process like this you deserve it!
    Happy Easter for you and your lovely family!

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    1. Thank you Rita, the process is one of the things I enjoy. I think that even if I didn't drink wine I might still want to make it.

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  8. Hi Jerry, Happy Easter to you and your whole family by Francesc and me.
    We are spending a few days in Barcelona, when we return to Mallorca, I will comment you your two interesting latest posts.
    A hug for everyone!

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    1. Thank you Sonia - Happy Easter to you both!

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  9. Hi Jerry, I just popped back to wish you and the family a Very Happy Easter and thank you for your kind and thoughtful wishes too. I hope your cold is improving and that the voice held up for Good Friday evening's singing!

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    1. Thanks Jan and a very Happy Easter to you too. The throat kept going long enough thanks.

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  10. jerry ....hope you and your family had a good easter .

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  11. Back again after taking Mel for a short walk and giving her dinner:) It's a long process, and takes a man of patience to complete.In your shed you are king, and deserve your reward:) Let us know how it turns out.The cushion made me smile.Hope you are feeling better of your cold:

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    1. Hope Mel enjoyed her walk! Yes it is a matter of waiting now to see if the whole Sap wine thing is worth the effort - one recipe says you should wait a year before trying it! Don't think I'll be quite that patient but it is amazing just how much country wines improve with time.

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  12. Hola Jerry, he leído todos tus post referentes a la preparación del vino. Tienes un laboratorio muy interesante con todo lo necesario, yo nunca imaginé que preparar esta clase de vino fuese tan laborioso. Tú has documentado muy bien todo el proceso de elaboración: con fotos interesantes y relatando paso a paso cada estado. Lo he leído con mucho interés y te admiro por la gran dedicación y paciencia que tienes :)
    No me queda claro si el vino ya esta finalizado o aún le queda al vino algunos meses para poder consumirlo.
    Saludos afectuosos, Sonia.

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    1. Hi Sonia, thanks for being so interested. Yes it is still fermenting but only very slowly now. In a few weeks time I will syphon off the wine to remove it from the deposit (dead yeast cells) that has settled at the bottom of the demijohn. Then leave it for a few more months to clear before bottling it.

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