Adding more dextrose

[doogle]

Hi all I have just finished the first fermentation stage for a coopers lager brew. My o.g was 1.040 (before adding the yeast) and my f.g is 1.020. If I was to now add more dextrose would this increase the strength of my brew. I have already put 1.25kg of dextrose in the brew which leads to my second question. Is there better dextroses to use or are they all the same. Thanks

 

[HaDaL]

You must give us some information about your brew such as type and weight of ingredients You've used,volume(batch size),temperature,yeast kind and pitching rate etc. Otherwise We can not help You.I think the data You specified do not seem normal and logical to me.However,in my opinion It's not a good idea to add sugar after the completion of fermentation.

 

[doogle]

Hi the mix I used is a tin pre mix which came with the brew kit. It is a 23l brew which I have made and it's just the normal yeast sachet that I used that comes with the tins. The temperature has varied between 23-28c. With regards to my readings which I used a hydrometer, the o.g read within the "beer start" markings on the hydrometer at the 40 mark. When I left the wort to ferment for a the specified period of time which was 5 days. I again used the same hydrometer which gave the reading inside the "beer finish" markings reading at 20 therefore only giving a alcohol strength of around 2.5%. The dextrose I used was just a mix from the local brew place.

 

[HaDaL]

Okay,1.25 kg sugar in 23 lit means that You've used just 1.5 kg LME therefore 1.040 is true.Regardless that you've used too much sugar(about half the original gravity) and It has its own drawbacks,You should look for the reasons have caused that high FG number.But at first We have to ensure that the fermentation of beer had been finished when You've read It's gravity.It is likely that You have measured the FG when fermentation had not been finished completely.Repeat the hydrometry 3 days after your last reading to ensure about that. Normally,If you have used reliable dextrose which is 100% fermentable your FG number ​​should be around 1.010.But If It still has stuck on 1.020, the problem can be due to one or more of the following causes;
- Using unfermentable sugars like dextrin or lactose instead of dextrose(note that dextrose, glucose and corn sugar are all the same) also I do not know what You mean by

The dextrose I used was just a mix

mix of what things?
- The yeast amount You've used had not been enough or had been expired thus there were small amounts of healthy cells around who could finish the job.It is not unlikely for some kits including old yeast sachets.
- Yeast cells had been shocked and dropped because of too low or less likely too high temperature.Also Keep in mind that the proper temperature for Ale fermentation is between 15 to 22 degrees Celsius not higher than that.High temp is the main cause of many problems in brewing.

 

[doogle]

That's interesting as to what you have said as I followed the instructions of the kit with regards to temp, dextrose amount. Also with regards to the dextrose I don't know the ingredients of it. I went into the local shop and picked up a bag which was labelled Dextrose that's all I know about it.

This is only my second brew and I do t understand what you mean when you said "You've used just 1.5 kg LME therefore 1.040 is true.Regardless that you've used too much sugar(about half the original gravity)" What is LME and how much dextrose should I of used?

 

[paperairplane]

Kit instructions give a basic rundown of the process, but are not optimal. Dextrose is corn sugar - as opposed to cane sugar which is normal table sugar.

5 days is not long enough for fermenation - need more like 3 weeks.

 

[melikidabeer]

First thing to do with those kits is bin the instructions and the yeast. LME is liquid malt extract and it's the stuff in the can. Don't use brewing sugars, buy a couple of packs of dry malt extract DME and add those instead. Healthy yeast will ferment that stuff down much more easily. Also, keep your temp down as much as possible and leave it in the fermenter for at least two weeks. Do these things next time and compare your results. When I do extract breeding, I used about 5 packs of DME and managed to make a really good Sierra Nevada clone, so you van get good results with the right yeast and steady temperatures.

 

[Calder]

First thing to do with those kits is bin the instructions and the yeast. LME is liquid malt extract and it's the stuff in the can. Don't use brewing sugars, buy a couple of packs of dry malt extract DME and add those instead. Healthy yeast will ferment that stuff down much more easily. Also, keep your temp down as much as possible and leave it in the fermenter for at least two weeks. Do these things next time and compare your results. When I do extract breeding, I used about 5 packs of DME and managed to make a really good Sierra Nevada clone, so you van get good results with the right yeast and steady temperatures.

I disagree. Yeast will work on simple sugars much more readily than extract. The resulting beer will not be as good. It all depends on what you are wanting from the beer; sometimes a little sugar can be good. 1.25 Kg is usually way too much.

 

[HaDaL]

Sorry about the delay doogle .Fortunately,I see others have answered your questions but friendly I would like to add something more;Don't do/follow what You don't know It's why or You can't predict It's results and don't use what You don't know what It is as well.Based on my experience these are important tips in brewing beer especially at the beginning.I would highly recommend You reading a good comprehensive book/ebook about homebrewing like the "How to Brew" by J.Palmer which is free(ebook version) or any other similar popular books that some of them are also available as free ebooks on the web.Hopefully You'll enjoy brewing beer more than drinking beer!

 

[doogle]

Hi all thank you for all your comments. My first batch tasted pretty good but I never measured the alcohol strength. I will certainly have a read of the book you recommended and see where it leads me. Just referring back to leaving it in the fermenter for 3 weeks is that before bottling? As there is no bubbles coming out of the air lock now. My last batch I had in the fermenter for 5 days then bottled it and left it for two months.