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Tuesday, February 21, 2012

Tesco Fast Action Dried Yeast - Review







The Tesco Fast Action Dried Yeast can be easily found in some Tesco shop in Ireland.
If we look at the back of the packet we can read


"A blend of dried yeast with yeast improvers"
Ingredients
Yeast (93%)
Calcium Sulphate
Emulsifier (Sorbitan Monostearate)
Flour treatment Agent (Ascorbit Acid)
Alpha Amylase


It is pretty clear that what Tesco sells for dried yeast, it is actually a blend of yeast and dough improvers.
Let's look now at the action of each of them

Calcum Sulphate = pH regulator

Emulsifier (Sorbitan Monostearate) = It is a chemical that are soluble in both water and oil and should strengthen the dough and act as a rehydrating factor

Ascorbic Acid = It strengthen the dough as an oxidiser which encourages the formation of cross-bonds interlinking the gluten network.

Alpha Amylase = From wiki "Amylases find use in bread making and to break down complex sugars, such as starch (found in flour), into simple sugars. Yeast then feeds on these simple sugars and converts it into the waste products of alcohol and CO2. This imparts flavour and causes the bread to rise. While amylases are found naturally in yeast cells, it takes time for the yeast to produce enough of these enzymes to break down significant quantities of starch in the bread. This is the reason for long fermented doughs such as sour dough. Modern bread making techniques have included amylases (often in the form of malted barley) into bread improver, thereby making the process faster and more practical for commercial use."


While it is kind of common to find ascorbic acid in Instant Yeast or Calcium Sulphate, I don't think that the presence of Alpha Amylase make this yeast suitable for long fermentation dough I would not recommend using the Tesco Dried Yeast Blend for serious home baking.

Measuring and Weighting Tesco Dried Yeast.

After few empirical test, I found that the following inequalities hold true

tsp = teaspoon
2 tsp= 2 teasoopn
1/2 tps = half teaspoon
1/4 tsp = tad
1/16 tsp = pinch
1/32 tsp = smidgen



2 tsp + 1/2 tsp + 1/4 tsp + 1/16 tps + 1/32 tsp < 7gr
2 tsp + 1/2 tsp + 1/4 tsp + 1/16 tps + 1/32 tsp + 1/32 tsp > 7gr
2 tsp + 1/2 tsp + 1/4 tsp + 1/16 tps + 1/32 tsp + 3/4 * 1/32 tsp =~ 7gr

The first two tells me that a teapoon of Tesco Dried Yeast must be
2.43gr < tsp < 2.46gr
The third says that it is likely that 1tsp = 2.44gr

So if you want to measure up Tesco Dried-Yeast (which is a blend)

1 tsp = 2.44gr
1/2 tsp = 1.22gr
1/4 tsp = tad = 0.6gr
1/8 tsp = dash = 0.3gr
1/16 tsp = pinch = 0.15gr
1/32 tsp = smidgen = 0.08gr
1/64 tsp = drop = 0.04gr


So if you need to prepare a 12hr Poolish which requires 0.2% of fresh yeast for 250gr of flour, using a conversion factor of 40% from frest to instant you get

250gr * 0.2% * 40% = 0.2gr
You will need a Pinch + a Drop of Instant Yeast
Or if you don't have a drop (not easy to find here in the shops in Dublin)
a Pinch + half a smidgen.

Dried Yeast in Ireland

I have been thinking for a while to swith from fresh yeast to the dried one, the main reasons are

1) Fresh Yeast is kind of difficult to find in Ireland, although most Polish shop should store it nowadays
2) When you manage to find it, it does not seem fresh to me. Fresh yeast should be crumbly, while the one I can buy it is not.
3) Fresh Yeast is persishable
4) Dried and fresh yeast should give the same final result if used properly
5) Very small quantity can be measured more accurately using measuring spoons and dried yeast, rather than
     fresh yeast with a digital scale with 1gr steps.

Dried Yeast available in Ireland

Tesco - Fast Action Dried Yeast
Allinson - Dried Active Yeast   allinson
Allinson - Easy Bake Yeast      allinson
McDougalls Dried Yeast Fast Action
DCL Yeast  Active dried Yeast  dclyeast

DCL Instant Yeast dclyeast
Doves Farm Original dry yeast  dovesfarm
Doves Farm quick yeast




Tesco - Fast Action Dried Yeast
It can be found in any Tesco shop
It's 99c 8x7gr sachet

Allinson - Easy Bake Yeast
I was able to find it here

Holland and Barrett
Henry Street, Dublin
17 Henry Street
Dublin 2
Phone:  00353 18749818

It's 1.29 Euros 2x7gr sachet (pretty expensive)

Allinson - Dried Active Yeast
I bought a tin of 125gr for 4 Euros at the Asian Food shop you can find at the end of Henry street.


Doves Farm quick yeast
This is listed on the Holland and Barrett Irish website, but I could not find it in store.



     

Monday, February 20, 2012

Frest, Active Dry and Instant Yeast

Most of my baking recipes are based on Fresh Yeast. Fresh Yeast is also commonly known as compressed yeast or cake yeast (in the USA).

The San Francisco baking institute suggest to use the following conversion formulas

1gr Fresh Yeast = 0.5gr Active Dry Yeast = 0.4gr Fast Action Yeast
100% Fresh Yeast = 50% Active Dry Yeast = 40% Fast Action Yeast.


This is an extract from the San Francisco Baking institure


Fresh Yeast vs Instant Yeast

It is common at our school to encounter the opinion that fresh yeast is superior to dry yeast. One baker even told us that when he switched from dry yeast to fresh yeast, the flavor of his bread improved. We would like to dispel the myth that fresh yeast produces better bread than dry yeast. In fact-if used properly-dry yeast will produce the exact same bread as fresh yeast. As long as the amounts are correct, the process is the same. It may even be the better choice in some situations, especially when you do not have a reliable source for fresh yeast. And, even if you do, instant yeast is a good back-up to have on hand in case you run out of fresh yeast. An unopened package of instant yeast has a shelf life of up to two years.

Active dry can be used at 50% of the weight of fresh yeast and instant dry can be used at 40% of the weight of fresh. Based on the recommendation of the yeast manufacturers, most people are under the impression that 33% is the proper conversion for instant yeast. This is true for an industrial process, but 40% is better in the artisan process, when dough temperatures are generally lower.

The instant form is the easiest to use since it does not need to be re-hydrated before adding to the dough. The only precaution is that it should not come in direct contact with cold temperatures and therefore should be mixed into the flour before adding water or added after the flour and water is incorporated.


-------

As the San Francisco Bakery Institue says, there should be no difference in flavour using the fresh Yeast (compressed yeast) as opposed to fast action if the latter is properly used.
In addion, where I leave, in Dublin is kind of difficult to find fresh yeast. The only place where I can find it is in Polish shops. Polish people love to use fresh yeast in their baking.
However, I must say that it does not seem to me very fresh.
On the oppisite side, Fast Action Yeast is readily available across the Country, it is easier to store, and it's no perishable, its shelf-life can be of 2-years if the sachet is not open. It comes in 7gr bags.
I couldn't find anywhere Active dry yeast. Aside the number of active cell, which is higher in the Fast Action Yeast, the main difference between the Active dry and the Fast Action is that the Active dry yeast needs to be activated with hot water, while the Fast Action goes into the dry ingredients - you should avoid to put it directly in contact with cold water.
The use of Fast Action Yeast bring about  the problem of how to weigh it accurately.

As an example let's suppose that we need to produce a 12hr poolish for 250gr of flour

100% Flour
100% Water
0.2%  Fresh Yeast
Temp 21 C

Doing a bit of math we need 0.5gr of Fresh Yeast for this poolish, which means

40% * 0.5gr =  0.2 gr of Fast Action Yeast!

This is really a tiny amount to measure.

To try to sort this problem out we can use measuring spoons. Since the volume of the Active dry yeast cell is pretty much constant from sachet to sachet,  a teaspoon should be a reliable way to weight the Fast Action yeast for tiny amounts, at least more reliable of a digital scale with a minimum step of 1gr.

Tonight I did some math and I came up with these two inequalities

tsp = tea spoon

3tsp > 7gr
2tsp + 1/2 tsp + 1/4 tsp < 7gr

which tells me that

2.33 < tsp  < 2.54

So a teaspoon of Fast Action Yeast must be something around 2.33 / 2.54 gr.

After some other investigation I believe that it should be pretty close to 2.47 grams.

In practical term we can assume

1 tsp = 2.5gr Fast Action Yeast
1/2 tsp =  1.25gr Fast Action Yeast
1/4 tsp =  0.62gr Fast Action Yeast

So to make our 12hr poolish we will need 1/3 of 1/4tsp!!!
I will give this a try and let you know how it goes.

Sunday, February 5, 2012

Gocciole Biscuits - Shortcrust Pastry method





Gocciole are are typical breakfast biscuits in Italy. The most popular ones are made by pavesi and can be found here. Most children go crazy for them, so I would recommend to all my readers to give it a try to see what they think about it.

You will find here a recipe that mix the ingredient as we are making a classic shortcrust pastry.
In a later post I will use exactly the same ingredients but we will mix them as if we were making a whipped shortcrust pastry.
As you will see there is going to be a material change in the texture of the final product, I will also use a cookie cutter. In this recipe I shaped them manually.



Ingredients

Stage Ingredients Gr. Baker% Method
1 Cream Flour
Butter
500
180
100%
36%
Mix flour and cold butter
(use a food processor)
2Sugar
Chocolate drops
Vanilla Powder
Baking Powder
200
100
0.5
10 (3 teaspoon)
40%
20%
0.1%
2%
Add all the other dried ingredients
and mix with the K-beater
3Eggs220%Add the eggs and keep mixing
Total1090.5218.1%



Processing Details

DetailsTemp/TimeInstructions
ScalingnoneHand up in a round ball.
Resting20-25minCover with cling film
Store in the fridge
ShapeTake 10gr of pastry
Hand up round
Flat it out pushing the palm of your hand on top
Give it a droplet shape
Resting20-25minCover biscuits with cling film
Store them in the fridge
Baking
Temperature
180Tray up on baking paper
Baking
Time
10-15 min


Step 1 of the ingredients table, is the typical way to create the classic shortcrust pastry. It is important that the butter is cold and that you use a good food processor. The final result should look like sandy. We call it in italian "sabbiatura", which means to make the butter and flour look like sand.
Step 2 and 3 are pretty easy.

Shaping: I shaped the biscuits for this recipe manually, but you can actually use a cookie cutter. If you do so, you don't have to weight them individually.



Hand up Round and cover with cling film


Batter after resting


Tray up



Biscuits after baking