Monday, August 13, 2007

kitchen essentials — dry & fresh yeast equivalencies

up until sometime in the 1930s in north america, yeast was only was available in its fresh state and sold commercially in small blocks or "cakes". while this was the standard, it was however somewhat inconvenient as few people had freezers, especially as we know them today, for prolonged storage; fresh yeast had (and still has) a short shelf life.

the innovative fleischmann brothers came up with the brilliant idea that yeast could be preserved in a dry state for much much longer storage than in its fresh state and over the next several decades, it became the standard. fresh yeast is virtually unavailable these days to the average consumer and difficult to find even in large cities.

in europe and other parts of the globe, this is another story. fresh yeast is still available in many a country and is the standard. when my parents first arrived in north america, they had no clue how to use the dried stuff and looked at it a bit suspiciously. to this day, they still opt for the fresh stuff.

luckily, i am able to procure my own stashes of fresh yeast. i measure it out and freeze it for those times i need it for baking. for a long time, i was always confused about using it in recipes which called for dry yeast (and vice versa). in fact, it became annoying having to sit there and scratch my head figuring it out each time.

so to make things more convenient, i ended up asking around and calculating and came up with the following information on the equivalent amounts for dry and fresh yeast.


1/4 oz fresh = 7.09 g
1/2 oz fresh = 14.18 g [1/2 oz when packed, ~ 17 - 19 g = 1 pkg dry yeast]
3/4 oz fresh = 21.26 g
1.0 oz fresh = 28.50 g


1 pkg dry yeast (standard in N.A.) = 2 1/4 tsp active dry = 0.6 oz fresh yeast [considered 1/2 oz cake]= ~ 17 g - 19 g fresh yeast.

* * * * *

i always use the following easy way to convert recipes:

1 packed tbsp fresh yeast = 2 tsp quick acting
("rapid rise") dry yeast = 2 1/4 tsp active dry (regular) yeast

2 oz cake = 3 pkgs yeast (eg. fleischmann's type)

* * * * *

the standard multiplier for calculating fresh yeast to dry is:

(to multiply) fresh amount "X" 0.4 eg. 1.5 oz fresh X 0.4 = 0.6 oz dry

* * * * *
what is fresh yeast? basically it's just yeast cells mixed with a starch, giving it its particular texture (somewhat rubbery and plasticine-like).

while there is only one kind of fresh baking yeast, there are several formulations for the dry variety:

regular type ["active dry"]: usually very small balls of yeast; this type of yeast is the standard and often recipes using it require two risings (to increase yeast colonization/amounts - yeast tends to grow exponentionally). must be proved before adding to a recipe with water or liquid at a specific temperature (warm).

active dry is basically fresh yeast which as been dried at a certain temperature; it's outer yeast cells are dead and form a protective shell around its inner live cells (approx. 30%). this is why it must be soaked first in warm water.

quick acting type ["rapid rise"]: different strain of yeast from active dry. granulation of yeast is smaller. contains ascorbic acid to increase loaf volume. this type can be mixed directly into the flour (recommended) or proved beforehand. a little less of it is required as it has a stronger formulation than the active dry. it only requires one rising period in most cases.

this type is dried at a different temperature and more live yeast cells are available making fermentation work faster.

breadmaker type: this is formulated for use in bread-making machines.
different strain of yeast from active dry. granulation is small. contains ascorbic acid to increase loaf volume.

instant yeast [european type]: this is like quick acting (rapid rise) yeast. it can be added directly to one's dry ingredients (recommended) and proves upon adding liquids. it is manufactured by companies like SAF and FERMIPAN. it is considered a very good baking yeast with a high percentage of live cells available. it can be proved before using also (though not necessary at all times) and is amenable to proving with either warm liquids or cool ones. the temperature of the liquid will affect the rate of proving.

both instant type and rapid rise are said to work better when mixed with the dry ingredients as opposed to the traditional active dry proving method. this dry-mixing technique works better due to the type of yeast strains of rapid rise and instant. both can still be successfully proved with liquid first however, with the same efficacy.


Emily DeVoto, Ph.D., said...

Thank you! The first time I bought bulk yeast it took me forever to figure out its equivalent in packets. I will bookmark this...

So why is fresh yeast better than dry?

Btw, I made the halvah shortbread again yesterday - thinner, and with half white sugar, half dark brown, no nuts - and it was a big hit (but I still got to keep a few pieces).

burekaboy — said...

hey em - grrr ... blogger didn't print my comment to you! ok, 2nd try:

you're welcome. until i sat down and figured all this out [and WROTE it down so i wouldn't have to search for calculations], it made me crazy. hope it helps (people). bookmark? just print it and stick it in one of your cookbooks :)

as for fresh yeast being better... meh, i think it's a matter of what you grew up with and are used to using. my parents were kind of odd when it came to some food things (ie narishkeit in my books). they thought it was dried out and dead (yeast). i guess some people are of the ilk that fresh is best.


glad to hear the shortbread came out well and all enjoyed it. see the difference when it's thinner?? do try it another time later on (lol, i'm sure you've had enough by now!) with the light brown sugar though.

Roo said...

I had an aunt that substituted yeast and flour for concrete mix - she was quite possibly the world's worst baker.

Though I had an uncle that was a Master-Baker (no sniggers) and his food was a delight.

My partner Peter, can make brilliant bread, just not often enough!

Oh and - you are officially immortalised in my "Scary Minds and more" section! :o)

burekaboy — said...

roo - LOL -> too funny, i just watched a 40s movie the other day about a crazy aunt burying her husband with cement to hide the body. good to know yeast and flour can sub for cement, HEHE ;)

do you guys (UKers) use fresh yeast or dry usually for baking? ... or has dry taken over there, too?

btw, thanks for the scary minds immortilization, just keep look over the left shoulder ... guaranteed i may arrive from the right though! LOL. oh yeah, and according the jacques (pepin) & friends, to become a master baker, i read that years of practice is required ;(o) where does one find the time? thank goodness for rapid rise yeast....

ps. get your other half to check out the dan lepard site if you want more bread!

Roo said...

I'll keep my eyes out for you, and recommend the Dan Lepard site to Peter ;o)

Mostly for convenience I think dried yeast has taken over, more to the point, when do people find time to bake now as it's no where near like my mother used to! I actually think it is a skill people do not have any more.

burekaboy — said...

hi roo - hi there. figured as much re: yeast .... everyone wants everything instantly these days. baking takes patience and time, two things people seem to have little of now, sadly enough. ps. i recommended the dan lepard bec it's UK-ish so i gather the ingredients, etc will be easier to follow. besides that, it's great stuff.