How long does IDY last?

[enchant]

Back in the spring, I bought a pound of IDY.  I put it in a bell jar and I store it in the fridge. After some experimentation and a lot of education here, I was getting pretty happy with my dough. 

During the summer, I got a nasty case of elbow tendinitis after overdoing it kayaking.  It was painful to do the simplest things like washing my hands.  So I had to stop making my own dough and made my pizza using frozen dough from the Piantedosi bakery here in the Boston area.

My tendinitis finally cleared up a couple months ago, so I started making my own dough again.  But I'm pretty unhappy with the results.  I still have some of the Piantedosi dough, and after a couple weeks of making my own dough, I'll use one of theirs, and it seems SO much better.  At the point where I'm about to stretch it, the dough has an extremely soft feel to it - very "pillow-ey".

I've tried a few things to try to improve my dough - using the whisk beater on my mixer to hydrate the flour better, but once the pizza is made, my dough just tastes like flour to me, while the Piantedosi dough tastes great.

So my question is this - What is the shelf life of IDY?  Has mine died or lost its potency?

[Pete-zza]

Pat,

The recommendations I gave at this post (Reply 1) seem to work pretty well:
http://www.pizzamaking.com/forum/index.php/topic,936.msg8349.html#msg8349. As you might expect, yeast producers tend to be more conservative in their advice on the storage of yeast (see, for example, http://www.safyeast.com/tips_using.html, http://www.breadworld.com/tipsterms/faq.asp, and http://www.redstaryeast.com/kneadednotes5.html).

In your case, if you kept the yeast in the refrigerator compartment since last spring, I wouldn’t be surprised to discover that its performance has deteriorated. If you kept it in the freezer, it should still perform. However, the differences you have noted in your dough as compared with the Piantedosi dough may be attributable to other factors, such as dough formulations. The quickest way to find out if the yeast is at fault is to buy a small packet and use it for your next dough.

Peter

[enchant]

The problem is that I've been having a hard time finding IDY locally.  Lots of ADY in the little packets.  I'll have to expand my search.

[November]

I've never seen a store sell ADY and not IDY.  That would be highly unusual.

[Pete-zza]

I know what enchant (Pat) is talking about. I cannot find instant dry yeast sold by that designation, or simply as "IDY", in the supermarkets near me, and I look at the yeast sections all the time. It is typically sold as bread machine yeast, which is usually supplemented with ascorbic acid (Vitamin C). There is also "RapidRise" ("instant active dry yeast") or "Quik-Rise" yeast ("fast acting yeast"), which arguably is a species of IDY but not sold as such. I once tried to get Fleischmann's to tell me whether the RapidRise yeast was an instant dry yeast and got only ambiguous answers and links to recipes. But after much prodding, I was told that it was not identical to instant dry yeast.

The yeast producers who sell IDY reserve that designation for professionals. The websites of the major yeast producers like SAF, Fleischmann's and Red Star tend to be consumer oriented and, from my research in the past, don't use the exact expression "instant dry yeast" or "IDY". You will find those designations on the products sold to professionals. Those are the products that are sold by the big box stores like Sam's, Costco's, etc.

If enchant stored his IDY in the refrigerator and is looking for a replacement, I would either buy a new bag or try one of the bread machine yeasts.

Peter

[November]

Peter,

I would also find it highly unusual for IDY to be labeled as such in the consumer market.  I was referring to bread machine yeast, which I can find just about anywhere yeast is sold.

- red.november

[enchant]

It is typically sold as bread machine yeast, which is usually supplemented with ascorbic acid (Vitamin C).

I have seen "bread machine yeast".  I'll pick up some of that and see if that improves things.

[November]

Some purists may not appreciate the ascorbic acid additive in bread machine yeast, but it actually helps to lower the pH and reacts to destroy disulphides, which is a very good thing.

[Wazza McG]

Hi November,

I have been using ascorbic acid (non flavoured powder - health shops) at 0.4 to 0.5 % (bakers %)  for a while now for the reason you state as the yeast likes the lower ph.  Could you please supply a bit more about the disulphides being destroyed and what the heck they are? 

My research suggests a very small amount of ginger and garlic powder would also help the yeast as well (similar percentages stated above).  At these percentages no flavour would be noticed - it would make just one happy yeast concoction - I would enjoy your thoughts.

I looked into this when I was searching for an alternative for a bread improver using a standard home oven to make better pizza's.

Grats,

Wazza McG

[November]

Wazza McG,

If the spelling threw you off, I'm sorry.  Every once in a while I revert to the old spelling of sulfur: sulphur.  You'll find more references under the modern spelling.  Disulfides (and sulfides in general) can form during fermentation when the yeast convert elemental sulfur into hydrogen sulfide.  That alone is nasty stuff, but then the hydrogen sulfide reacts with ethanol or acetaldehyde (produced by yeast) to form thiols or mercaptans.  At various stages these can either be oxidized by acid into disulfides for the yeast to turn back into mercaptans, or oxidized by the acid to form less reactive mercaptans.  Thiols smell horrible, and highly reactive mercaptans smell like rubber.  The idea is to interrupt the hydrogen sulfide from reacting or to play a role in creating less reactive (higher odor threshold) sulfur based compounds.

Ginger yes, garlic no.

- red.november

[November]

Since you're probably going to ask why not garlic (and onion for that matter), it's because garlic contains allicin, and has been found to disrupt yeast enzyme activity.

http://iadr.confex.com/iadr/2004Hawaii/techprogram/abstract_46954.htm

- red.november