Using lactase, adding yeast or ... ?

[sven.vandevenne]

Hi all, I've very eagerly followed the thread on lactomel, which gave me a lot of inspiration. So what I did is the following:
- 3/4 of full fat milk right from the farm
- 1/4 of honey
- 1g/liter mead yeast
- servomyces yeast nutrition at 24/48h
- Some flavors like vanilla, lavender and blueberries (in different batches each)

Now, at this point we're 12 days in. I racked the mead to get rid of the curds and the yeast has (almost) stopped, which I assume from the airlock not bubbling and the mead getting clearer in opacity (though not completely see-through yet), as you can see in the pic included. However, I'm currently stuck at a gravity of about 1.050, which was not my intention. I wanted to make a dry lactomel.

I deduced from reading all the threads in the Lactomel group effort thread that it's probably the lactose that is unfermentable. I gave some extra yeast nutrition 2 days ago, though it has been consistently warm (± 25°C) for the last 3-4 days. The package of this yeast says it can take up to 30°, so I assume it should still be fine.

Now the real question is: should I use lactase tablets to break down the lactose and make it (partly) fermentable, should I add some more yeast or both? I have one small test batch without added aromatics, so I can get "crazy" on that one.

Also, for future experiments, do you think I should dilute it with water and add some more honey to get to the right OG?

Hope you can share some advice

Thanks in advance!

 

[bernardsmith]

Hi, sven.vandevenn and welcome. Sorry but not enough information. Not clear what the volumes you are referring to in fact are. 3/4 of what? A quarter of what? Milk rather than whey has a great deal of fat and other proteins so the gravity you may have taken will not accurately reflect the sugar content of your mead. Not necessarily a problem but since we do not know the amount of fermentable sugars (the honey) we cannot how much more tolerance the yeast may have. You also fail to provide us with the specific yeast you pitched.
Adding lactase will break down ALL the lactose into glucose and galactose and both are fully fermentable. My experience as both a wine maker and a maker of cheese who frequently ferments the leftover whey is that the whey has about 20 points of sugar (perhaps a little more as my cultures transform some of the lactose into lactic acid when I make my hard cheeses. Twenty points (1.020) should ferment out if you add enough lactase. Not a microbiologist so I have no idea of how the fat and protein content of your milk will affect the current gravity. You may want to contact a local university that offers courses in cheese making or dairy science.
For future meads, I would suggest that you make either a soft cheese or a hard cheese (adding lemon juice for the first or bacterial cultures (say live kefir), for the second so you are fermenting on (no lactase) or with (lactase added) the whey. Most of the fats , the proteins, the cassein, etc will be in the cheese and the whey should be almost water and lactose (with either citric acid or lactic acid). I say, most of the fats etc should be in the cheese, because when many make many different kinds of cheese, they are also able to make ricotta from the whey. I usually cannot, as my whey has too little of the products needed for the ricotta.

 

[sven.vandevenne]

Hi, sven.vandevenn and welcome. Sorry but not enough information. Not clear what the volumes you are referring to in fact are. 3/4 of what? A quarter of what? Milk rather than whey has a great deal of fat and other proteins so the gravity you may have taken will not accurately reflect the sugar content of your mead. Not necessarily a problem but since we do not know the amount of fermentable sugars (the honey) we cannot how much more tolerance the yeast may have. You also fail to provide us with the specific yeast you pitched.
Adding lactase will break down ALL the lactose into glucose and galactose and both are fully fermentable. My experience as both a wine maker and a maker of cheese who frequently ferments the leftover whey is that the whey has about 20 points of sugar (perhaps a little more as my cultures transform some of the lactose into lactic acid when I make my hard cheeses. Twenty points (1.020) should ferment out if you add enough lactase. Not a microbiologist so I have no idea of how the fat and protein content of your milk will affect the current gravity. You may want to contact a local university that offers courses in cheese making or dairy science.
For future meads, I would suggest that you make either a soft cheese or a hard cheese (adding lemon juice for the first or bacterial cultures (say live kefir), for the second so you are fermenting on (no lactase) or with (lactase added) the whey. Most of the fats , the proteins, the cassein, etc will be in the cheese and the whey should be almost water and lactose (with either citric acid or lactic acid). I say, most of the fats etc should be in the cheese, because when many make many different kinds of cheese, they are also able to make ricotta from the whey. I usually cannot, as my whey has too little of the products needed for the ricotta.

Oh yeah, sorry for the confusion. I guess it shows I'm a beginner
I used the following amounts:
600 ml milk
200 g honey
0.8 g Mangrove Jack's Mead yeast 05

 

[bernardsmith]

so we are talking about 800 ml of meead or about 1/5 of a gallon (US)? So about the equivalent of 35 oz of honey in one US gallon or slightly more than a starting gravity of 1.070- 1.080 from only the honey, then I would think that this may have stalled. You may want to upturn the process to see if you can restart this by creating a new starter with a fresh pack of yeast (you did use the whole pack, right?) and say, a cup of water (at say 100 F) with say a tablespoon of honey or sugar. Allow the yeast to start frothing and blooming and when it has add a cup of the stalled batch to this starter. if your starter is in a carboy with bung and airlock, watch for the 2 cups producing enough carbon dioxide to make the airlock bubble. When this is actively bubbling add the same amount of mead from the problem container to the starter so that there is now 4 cups in the starter... (you are always doubling the volume in the starter each time you add , observe for activity and take more from the stalled batch. This can take a few hours but it tends to resolve systemic problems in the batch.

 

[sven.vandevenne]

so we are talking about 800 ml of meead or about 1/5 of a gallon (US)? So about the equivalent of 35 oz of honey in one US gallon or slightly more than a starting gravity of 1.070- 1.080 from only the honey, then I would think that this may have stalled. You may want to upturn the process to see if you can restart this by creating a new starter with a fresh pack of yeast (you did use the whole pack, right?) and say, a cup of water (at say 100 F) with say a tablespoon of honey or sugar. Allow the yeast to start frothing and blooming and when it has add a cup of the stalled batch to this starter. if your starter is in a carboy with bung and airlock, watch for the 2 cups producing enough carbon dioxide to make the airlock bubble. When this is actively bubbling add the same amount of mead from the problem container to the starter so that there is now 4 cups in the starter... (you are always doubling the volume in the starter each time you add , observe for activity and take more from the stalled batch. This can take a few hours but it tends to resolve systemic problems in the batch.

Thanks for taking the time to explain that into detail!

Yes, that would be about 800 ml or 1/5 of a gallon of mead. So, if I got that right, what you are talking about is using a new starter to get it back up on its feet and eventually diluting it so there's less unfermentable sugars?

I think, for the sake of experimenting, I'll try your first approach and add lactase so the sugars in my current batch become available. I didn't use the whole package of yeast because it's 10 g, which, what I got from reading, is used for 10 liters (± 2.6 gallon), so I still have some left to do a new starter like you described.

Though I am also kind of curious whether it will start on it's own, but it's probably better to give it a good kickstart, no?