dme for yeast?

[lawlslawls]

I'm wondering what the differences are between beer yeast and wine yeast; beer yeast starters are made with DME, but I've read that wine starters might not be able to digest dme?

 

[Yooper]

Wine yeast is cultivated to ferment simple sugars- dextrose (a monosaccharaide) and glucose and fructose (disaccharides). Wine yeast strains would not ferment maltriose but may be able to ferment maltose although somewhat poorly.

 

[lawlslawls]

so is sucrose easily digested by wine yeast?

 

[Yooper]

so is sucrose easily digested by wine yeast?

Yes, absolutely. It will ferment sucrose 100%, until the alcohol tolerance of the yeast strain is met.

 

[lawlslawls]

does fermenting sucrose with wine yeast produce the same off flavors that fermenting sucrose with beer yeast does?

 

[Yooper]

does fermenting sucrose with wine yeast produce the same off flavors that fermenting sucrose with beer yeast does?

I don't know of any off flavors associated with ale yeast and sucrose, so I'm not sure what you're asking?

 

[Jacob_Marley]

does fermenting sucrose with wine yeast produce the same off flavors that fermenting sucrose with beer yeast does?

Ale yeast? Sucrose?

Off flavor due to using sucrose in wine? Never heard of such a thing. Curious.

Did you mean to post this on one of the brewing forums? (ah ... yer in the wine forum right now)

You might have your concepts a bit twisted around? ... I'm wondering if you are talking about an issue you heard about with brewing beer?
Fermenting a lot of sugar while brewing, sucrose included, can be an issue.
I suppose there would be your sucrose and there would be your ale yeast.

If you mean a kinda winey/cidery flavor when some beer is brewed; I'm not sure if I'd characterize that as a fault (says the winemaker ;-) ... if that is the effect you are asking about, joking aside, that's not the yeast ... it's using sugar.

Not an issue in wine ... an issue in beer though.

Any straight sugar ... fructose, glucose, sucrose ... will have those slight estery notes if there is not enough malt being fermented to "mask" it. The more malt, and the fresher the malt, the better the masking.
I suppose any yeast that is a better ester producer in theory runs a bit higher risk; but in general would not think the yeast is of a specific cause-and-effect though. It's the masking effect of the malt or the lack thereof.

For what it's worth, while I'm all out in left field again (woo-hoo) ... when brewing (that would be beer) with sugar, a high level of a product like Fermaid K might also help avoid the effect (thank you Clayton Cone), allowing a higher percentage of sugar to malt without the development of that flavor profile. I'm just taking the Good Doctor's word on that one.

If in fact you do mean wine though ... then I have no idea. Off hand I can't think of any "off flavors" from, in specific, solely fermenting sucrose.

 

[bernardsmith]

More to the point perhaps is that the OP begs the question about any need to make a yeast starter for wine. Typically wine makers don't make starters. The sugars are easily fermented, the yeast is biting at the bit to ferment and dry yeast packages have easily enough viable yeast cells to chomp through 5 or 6 gallons of must without any problem. The one time that a "starter" might be used is in making Skeeter Pee (a fruit wine made from lemon concentrate). Here the must is very acidic and it is best to pitch not fresh yeast but the slurry from another batch. The slurry is more likely to tolerate the acid bath that it is being asked to ferment, but I have made batches of SP using dried yeast and have not had any trouble. I guess wine yeast is just more ...um... robust than the ale variety

 

[lawlslawls]

More to the point perhaps is that the OP begs the question about any need to make a yeast starter for wine. Typically wine makers don't make starters. The sugars are easily fermented, the yeast is biting at the bit to ferment and dry yeast packages have easily enough viable yeast cells to chomp through 5 or 6 gallons of must without any problem. The one time that a "starter" might be used is in making Skeeter Pee (a fruit wine made from lemon concentrate). Here the must is very acidic and it is best to pitch not fresh yeast but the slurry from another batch. The slurry is more likely to tolerate the acid bath that it is being asked to ferment, but I have made batches of SP using dried yeast and have not had any trouble. I guess wine yeast is just more ...um... robust than the ale variety

perhaps wine yeast is more robust than ale yeast. one typically avoids making an ale yeast starter with simple sugars, in order to prevent the yeast from losing the ability to convert the higher sugars that are present in wort. I suppose the 'off flavors' that I spoke of are considered inappropriate for beer, but are not considered inappropriate for wine

 

[Yooper]

perhaps wine yeast is more robust than ale yeast. one typically avoids making an ale yeast starter with simple sugars, in order to prevent the yeast from losing the ability to convert the higher sugars that are present in wort. I suppose the 'off flavors' that I spoke of are considered inappropriate for beer, but are not considered inappropriate for wine

Correct- it's not that ale yeast can't ferment sucrose- it certainly can and some beer styles do have sucrose added to it (Belgians, IIPAs, etc). The problem with ale yeast is that if a starter is made with sucrose, it will preferentially look for sucrose, and struggle with maltose or maltrotriose and end up with an incomplete fermentation. That's why a starter for ales and lagers are made with wort- so that the yeast is cultivated to ferment maltose and maltrotriose.

Simple sugar, used judiciously in an ale recipe is just fine. It doesn't create off flavors.