ale vs wine yeast - a question

[bernardsmith]

Does anyone know why wine yeast is packaged in packs half the size of ale yeast when both brewers and wine makers are typically making about 5 gallons a time? Is this just the convention or is there a reason why brewers may need more yeast when they pitch than wine makers need? Just curious.

 

[Maylar]

Interesting question. You'd think it'd be the other way around, since higher gravity musts require a higher pitch rate.

 

[Weezy]

My boss is a big wine maker, making hundreds of gallons at a time. They pitch at 1/2 g/gal but they use a goferm starter.

Most Vintners don't know much about yeast health.

And we may be pitching more than we need a lot of times as well.

 

[bernardsmith]

Right but that does not really explain why labs that pack yeast for wine making sell you 5 g per package while labs that pack yeast for brewing pack 11.5 g. How much you use is your business but the packs all say that they are good for 5 -6 gallons. So it seems that beers need twice the amount of yeast to ferment the same volume. Is there a biological reason for the different size of the packs or is this just an historical accident?

 

[Yooper]

Ale yeasts are generally used for beer, although I've used them in cider. Beer's wort is comprised of all sorts of things like maltose, maltotiose, glucose, fructose, and so on. There are few monosaccharides, and most are dissaccharides, while some are trisaccharides.

Wine is generally comprised of glucose and fructose but mostly water. I think the literature I've seen quotes wine must composition as 70% water. Anyway, those are easily fermentable by wine yeast so the pitching rate doesn't need to be as high as with less fermentable worts like you'd find in beer.

 

[bernardsmith]

Ale yeasts are generally used for beer, although I've used them in cider. Beer's wort is comprised of all sorts of things like maltose, maltotiose, glucose, fructose, and so on. There are few monosaccharides, and most are dissaccharides, while some are trisaccharides.

Wine is generally comprised of glucose and fructose but mostly water. I think the literature I've seen quotes wine must composition as 70% water. Anyway, those are easily fermentable by wine yeast so the pitching rate doesn't need to be as high as with less fermentable worts like you'd find in beer.

Okay - so wouldn't that suggest that wine yeasts should be packed with fewer yeast cells than ale/beer yeasts? But if I buy say, Safale US-05 I am going to have a pack with 11.5 g (including filler) but if I buy, say 71B the pack will have 5 g (including filler)... Does the wort need a higher cell count than the must? Why?

 

[dmtaylor]

Excellent questions. I think it is a historical thing, the manufacturers have always packaged wine yeasts like that and not many people ever complained, so it stays that way. Wine makers just haven't made a big stink about yeast in the same way that the overly obsessive homebrewers of beer have. And then along comes mrmalty.com, which I'm sure most winemakers never heard of but EVERY homebrewer has heard of, and it's based on super-conservative amounts of yeast to be used, which has promoted a larger amount of beer yeast per package.

Personally, I think mrmalty.com is way off and I think the 5 gram package for 5 gallons of anything is enough. Also I think it's almost impossible to screw up a wine or a cider, it's just so dang easy to make, while brewing beer is in fact a little bit more complicated, and a little more touchy, and thus explains part of the obsessive behavior by homebrewers. They're looking for scapegoats when their beer doesn't turn out perfectly, and often times the scapegoat is yeast pitching rate, yeast health, etc., when in fact they may just be sh***y brewers.

In closing I'll leave you with a recent revelatory theory I put out on the AHA forum about dry yeast packs for beer having WAY too much yeast for our needs, which was essentially confirmed from what I can tell, or at least, that's my story and I'm sticking to it.

https://www.homebrewersassociation.org/forum/index.php?topic=27438.0

Cheers.

 

[JLump]

I guess what Yooper is saying is that because wine must is composed of a much higher proportion of SIMPLE sugars, there is less work on the yeast's part to get the job done despite the higher gravity.

 

[dmtaylor]

I would think the wine yeast has to work pretty hard to get down to 0.994 SG and ~12% ABV. Maybe it really is easy. But beer yeasts still always crap out way earlier than the wine yeasts, except for Belle Saison and its kin, which I've heard rumored might actually be a wine yeast stolen for beer brewing.

 

[Yooper]

I guess what Yooper is saying is that because wine must is composed of a much higher proportion of SIMPLE sugars, there is less work on the yeast's part to get the job done despite the higher gravity.

Yes, and wine yeast is specially created to ferment simple sugars. It doesn't go a great job with maltotriose, for example, but shines when fermenting sucrose/fructose/glucose. While they are still are saccharomyces cerevisiae, the different strains are produced to provide different characteristics. Different alcohol tolerances (some easily up to 18%), some produce more esters, some need more nitrogen, etc, but all do very well with simple sugars. I never use Saccharomyces bayanus, so I can't comment on that one.

Here's a chart I use that has many of my favorite wine yeast strains on it, to show the characteristics: http://www.piwine.com/media/pdf/yeast-selection-chart.pdf What is interesting is the part of the chart showing how much H2S (relative to other strains) is produced with the lack of nitrogen. It shows differences in strains, other than the ABV tolerance.

Wine yeast are perfect for making wine, and the pitching rate can be pretty darn low with great results in a must with plenty of nutrients. Luckily, most fruit musts contain plenty of nutrients, except for (sometimes) nitrogen and it's often added when mixing up the must.