Gluten: W, P/L and the problem with durum

Baking professionals in Italy commonly refer to the strength of flour by its W index, describing this as its “force”.

Italian Millers provide much data in their flour specifications often including rheological properties recorded by the Chopin-Alveograph. Testing performed by the Alveograph involves forcing air into a piece of dough causing it to expand like a balloon until it bursts, at which point the test is complete. The data is recorded on a graph as a line measured in millimetres. The pressure required and therefore resistance of the dough is measured as P. The final size of the dough is measured as L, this being it’s extensibility. The area under the line is represented by W which indicates overall strength.


The index of W.

Up to W170 (weak): for biscuits, waffles and tender baked sweets;  for béchamel and thickened sauces.

From W180 to W260 (average): French bread, bread rolls, pizza, pasta.

From W280 to W350 (strong): classic bread, pizza, pasta, baba, brioche.

Above W350 (very strong): Made with particular types of wheat, that are used to reinforce weaker flours. Ideal for highly enriched doughs subjected to long leavening, Often referred to as “Manitoba”.


Extensibility, elasticity and quality.

Gluten consisting of proteins gliadin and glutenin is the one, which supports the dough. The higher the content of the gluten, the stronger is the flour. However, the amount of gluten does not determine everything, its characteristics are also important. The strength of the flour is more dependent on the properties of gluten. Two flours may have the same amount of gluten, though, one may be stronger and the other weaker.

Gliadin in contact with the water forms a fluid sticky mass, while glutenin absorbing water, forms a compact mass, elastic and resistant. The wet gluten possesses all the mechanical properties of the two proteins. Obviously, for a flour to be strong it must have glutenins in the majority. If a meal has a high amount of gluten, but this consists mainly from gliadin, the flour can not be very strong, because its gluten is soft and slightly spongy.


P/L and Durum

Instead of referring to them individually the balance between extensibility and resistance can be expressed with the P/L ratio, the optimal being between 0.5 – 0.6. With a P/L ratio higher than 0.7 the flour is very resistant, lower than 0.4 it is very weak and extensible. Soft wheat flour is naturally extensible while hard wheat flours are naturally more tenacious this is especially true with durum, the hardest wheat of all, where a typical P/L ratio can be above 1 and even exceeding 2.

Durum wheat doughs are distinguished by a high resistance to deformation and consequently limited extensibility. To be judged sustainable for bread making the semolina must have a protein content >12%, a good farinographic stability and alveograph P/L index value below 1. However it should be noted that the bread-making process preferred in the case of durum wheat requires the use of sourdough. A case in point is the pane di Altamura. The proteolytic activities of semolina and/or of the lactobacilli may produce considerable changes in the rheological properties of the gluten network, reducing the natural excessive elasticity of dough made from durum wheat.


Numerous factors brought about by fermentation and inclusion of other ingredients will affect the properties of gluten, even water quality. Water too hard being rich in minerals will make gluten more tenacious reflecting an increase in the P/L ratio. Soft water will create the opposite effect making gluten softer and more extensible reflecting a reduction in the P/L ratio.

Panettone di Giorilli

Piergiorgio Giorilli is a baker in a league of his own. His years of experience and effortless skills speak volumes. He is a true master! I have known of Giorilli for sometime now, yet I haven’t until now made a panettone in accordance with his methods and formula.

Processing of the mother dough is a skill that requires tuition and above all else experience. Giorilli opts to maintain his madre in water during the standard 12 hour period. While as typical, before proceeding to the first dough three refreshments are made lasting 4 hours each time.

From I sourced his recipe. I adapted his formula to make two 500 gram panettoni, flavoured with the traditional sultanas, orange and citron.

Primo impasto

69g lievito madre mature
75g sugar
120g water
54g egg yolks
72g butter
240g flour

Secondo impasto

60g flour
66g sugar
4g salt
96g egg yolks
129g butter
2g malt
120g sultanas
60g candied orange peel
30g candied citron

aromatic mix x2

30g acacia honey
vanilla pod seeds
orange zest
lemon zest


Panettone al Cioccolato di Iginio Massari

Sweet Alcohol aroma not sharp
Taste of Mozzarella, no bitter aftertaste
Soft ivory-white dough with elongated alveoli
pH 4.1

Feeding procedure that lead to mature lievito:

Tues. 00.00 1:1 – 12hrs @ ~18C
Tues. 12.00 1:1 – 12hrs @ ~18C
Wed. 00.00 1:1 – 17hrs @ ~18C
Wed. 17.00 1:1 – 18hrs @ ~18C
Thurs. 11.00 1:1 – 4hrs @ 28C
Thurs. 15.00 1:2 – 4hrs @ 28C – here ratio 1:2 to adjust for lievito too strong!
Thurs. 19.00 1:1 –15.5hrs @ ~18C
Fri. 10.30 1:1.5 – 4hrs @ 28C
Fri. 14.30 1:1 – 4hrs @ 28C
Fri. 18.30 1:1 – 4hrs @ 28C

Fri 22.30 – Primo Impasto

Lievito was put into a bath at the end of the storage phase at ~18C before the next refreshment.

Panettone Al Cioccolato di Iginio Massari

60    1000 Lievito
240    4000 Flour 280-320
60    1000 Sugar
81    1350 Butter
60    1000 yolks
78    1300 water

60    1000 flour 280-320
—-    3n vanilla
60    1000 yolks
72    1200 sugar
21    350 honey
93    1550 butter
4.8      80 salt
42     700 water
60    1000 cioccolato fondente
60    1000 cioccolato latte
60    1000 candied orange
1111.8    18530

Panettone di Rolando Morandin

… con cioccolato.

I follow Morandin’s method of keeping the madre in water all the time. Making three refreshments every 3 hours.

I subbed fruit for dark lindt chocolate.

Panettone di Rolando Morandin

200.0    4000 Flour
87.5    1750 sugar
50.0    1000 water
112.5    2250 yolks
100.0    2000 lievito
25.0     500 water
125.0    2500 butter

50.0    1000 flour
17.5     350 sugar
22.5     450 yolks
25.0     500 butter
  6.0     120 salt
150.0    3000 orange
100.0    2000 sultanas
50.0    1000 cedro