Stiff Starter Whole Wheat Sandwich Loaf with Wheat Germ

Revisiting the Stiff Starter Whole Wheat Sandwich Loaf, which I've been playing with recently, e.g. here and here.  I had to see if it would work with the 5% wheat germ put back into the dough (as reported here).  I also wanted to see if I could make a multigrain loaf using this method.  And I wanted to experiment with the temperature, to see what might happen to the crust.

So, three doughs.

1. Multigrain loaf #1

Here I am considering the total flour added to the dough to be 700g still, but I am backing off of it slightly because I am adding some 8-grain mix, which will soak up some of the water.  I still use the amount 700g for basic calculations (e.g. to calculate how much wheat germ gets used).  I think that this is the loaf that looked the best, and I gave it away to my niece:

• Stiff Starter: 300g (Contains 200g of ww flour)
• Water: 700g
• WW flour: 650g 
• 8-grain Mix: 65g
• Salt: 18g
• Wheat germ: 45g (5% of 900g)

2.  Control Loaf

Here I've used all of the whole wheat, but added none of the multigrain mix.

• Stiff Starter: 300g (Contains 200g of ww flour)
• Water: 700g
• WW flour: 700g 
• Salt: 18g
• Wheat germ: 45g (5% of 900g)

3. Oregano Loaf

I have been thinking of trying this loaf ever since I bought some ground oregano at Arva Mills.  I like the taste of oregano, but I've never seen it ground so fine as flour like this, and seeing it gave me the idea.  Twelve grams doesn't sound like a lot, but it is probably about 3 Tbsp, the stuff doesn't weigh much.  I wondered if it would turn my dough green.  It didn't, because the flour is whole wheat, but it made it noticeably darker, sort of grey.  The oregano changed the structure of the gluten entirely, making it incredibly tighter, as if it were soaking up way more water than the other loaves that had multigrain.

• Stiff Starter: 300g (Contains 200g of ww flour)
• Water: 700g
• WW flour: 700g 
• Salt: 18g
• Wheat germ: 45g (5% of 900g)
• Ground oregano: 12g (1.34% of 900g)

This is the loaf that I tried the so-called optimized baking time and temperature for lighter coloured loaves (report on that follows, in the section "Crust"):

7 minutes at 115 ℃ (239 ℉)

7 minutes at 130 ℃ (266 ℉)

7 minutes at 156 ℃ (313 ℉)

7 minutes at 176 ℃ (349 ℉)

This didn't work at all for my slightly overproofed whole wheat loaf.  It was already dripping in the humid afternoon heat, and my attempt at doing a "comb-over" of the dough just prior to dumping it into the oven didn't work.  In the low oven temperatures for the first stage, the dough merely drooped back over the edge of the tin and fell into my steam-pan.  After the 28 minutes of baking, the loaf didn't look or feel done, so I upped the temperature to 450 degrees and kept it in the oven for another 14 minutes.

The dough has an unusual purplish tint to it, almost as if I were baking it with walnuts.  It has a lovely sagey scent (very interesting while baking), but the bread is a bit too sour to make any final judgements on its taste.  "Smells like pizza," my wife said.

This loaf, if properly made, would be interesting with different cheeses.  And perhaps with dried tomatoes.  

Mixing photos

Crumb Results


The Oregano Loaf:

The Control Loaf:

Crust

Ever since I traveled to Goderich to try Burdan's bread, I've been thinking about crust.  My experiments with trying to make my whole grain half-rye bread's crust lighter can be found with a discussion of Burdan's bread.  In my research, I've been asking the questions:

• "what is healthier, light crust, or dark crust?"
• "what is the optimal temperature and time of baking to bake a loaf with the least possible loss of flavour?"
• "What is the best time and temperature for baking bread that will bake the interior of the loaf but keep the crust as light as possible in colour?"
• "Does baking bread in an optimal way have an effect on staling -- either minimizing staling, or hastening it?"

These questions show that I still have a lot to learn about bread.  Things are a bit more complex than you can imagine.  In casting about for answers, I've developed even more questions.  But I've also uncovered a few facts about crust.

The Thermal Effects of baking on Flavour

It has long been known (e.g. Johnson, J. and El-Dash, A. (1969). Role of Nonvolatile Compounds in Bread Flavor. J. Agr. Food Chem  pp 740-746) that the flavour of typical bread (unless you add sugar or other flavouring ingredients) comes from essentially two things: the fermentation of the loaf, which releases lots of volatile molecules, and the baking temperature.  

For now, let's just consider the thermal effects.  A lot of flavour is developed during the heating of the loaf, when the sugars present in the dough undergo the Maillard reaction and caramelize.

If you are going to have a loaf of bread with a very light crust, you are going to miss out on some of the flavour notes of a darker, roasted-grain crust.  It may be healthier (or it may not -- the jury is still out on this one).

The Four Stages of Bread Baking, derived from Crust Colour:

I've mentioned Onishi's article previously; here I'll discuss it a bit more.  Onishi and his team of bread researchers (mostly from Japan) used colorimetry to define four stages of bread baking:

1. pre-heating (surface temperature <110 ℃ )
2. Maillard reaction (110-114 ℃ ) (crust browning begins)
3. caramelization and carbonization (150-200 ℃ )
4. overbaking (surface temperature >200 ℃ )

Onishi determined that the colour of the crust was a good indicator that could be used to monitor and control baking conditions.  It must be remembered that the oven air temperature is not the same as loaf temperature.  Time, temperature, and ingredients (especially water) are key to predicting how a given recipe will behave.  Vapour within the oven and within the loaf also must be well understood, along with the resultant pressures these gases impart at various temperatures.  

Although they did derive a mathematical formula that explained the data they collected, Onishi's team indicated that breads with different ingredients may require individualized formula.  But they nevertheless proved that there was a linear relationship between the colour of their loaves and the weight loss, such that the darker the crust, the more the weight loss of the bread.

Onishi et. al. (2011) "Characteristic Coloring Curve for White Bread during Baking" Biosci. Biotechnol. Biochem. 75(2) pp 255-260

Optimizing Baking Temperatures for minimal weight loss

We cannot equate bread's weight loss with the loss of a bread's flavour.  As Johnson and El-Dash showed, flavour can be enhanced with temperature; and we know that dried food will sometimes concentrate flavours.  Nevertheless, bakers want to know that the loaves they are baking have a consistent weight.  And the first step toward having consistent flavour might be having a loaf that maintains its mass through the baking process, losing no more than around 8% (a number that I've seen in some articles) during baking due to evaporation.

One of the articles I read while researching crust was Therdthai, N. et. al. (2001) "Optimisation of the temperature profile in bread baking". ThaiScience

This essay examined the mechanized browning of white bread crusts in an industrial oven, to optimize the best temperatures for loaves in order to achieve a completely baked and finished crumb, with minimal weight loss, and with a subjectively pleasing crust.  Therdthai's team used tins to hold the dough, and had to take into account the way the tin had to be heated first before imparting the heat to the loaf.  Although they were looking only at white bread, their results are interesting.

"Intuitively, to reduce the weight loss, either the baking time and/or the baking temperature has to be reduced.  However, bread has to be properly baked."

I enjoyed reading this article.  I do not know how arbitrarily it defines the steps, but I was intrigued that Therdthai's research group proposed 3 stages of bread as it undergoes baking, but adjusted this to fit the 4-step model of modern industrial baking equipment:

1. Stage 1: 1/4 of the total baking time (6.84 min):   Optimum temperature 115 ℃ (239 ℉)

• Outer crumb increases 47 ℃ a minute to 60 ℃ (40℉ per minute to 140℉)
• this enhances enzyme activity and yeast growth resulting in oven rise
• starch is hydrolyzed by amylase, resulting in sucrose, glucose and maltose.  Yeast uses this and via fermentation produces carbon dioxide gas, which is dissolved into the water.  
• When the yeast is killed, the CO2 is released, resulting in volume increases by 1/3 original.
• surface skin loses elasticity, thickens, begins to brown in colour.

2. Stage 2: 1/2 of the total baking time (13.68 min): Optimum temperature: 130 ℃ (266 ℉), then 156 ℃ (312.8 ℉) for 27.4 min. each

• crumb temperature increases 5.4 ℃ per minute to 98.4 - 98.9 ℃.  (42 ℉ per minute to 209 - 210 ℉)
• all reactions are maximized, including moisture evaporation, starch gelatinization and protein coagulation.
• (starch gelatinization should be 0.98-0.99% complete at internal temperatures of 95-98 ℃)
• Dough becomes crumb in structure from outer to inner portions by penetrating heat.
• Most of the weight loss comes from the second part of this stage, from water evaporation at the outermost layer

3. Stage 3: 1/4 of the total baking time (6.84 min): Optimum temperature: 176 ℃ for 27.4 min (348.8 ℉)

• a typical browning crust is observed when crust temperature reaches 150-205 ℃ (284 - 401 ℉) by Maillard reaction
• the volatilization of organic substances is designated as the bake-out-loss; but there is less overall weight loss, compared to the previous stage.
• Internal temperature will increase to 100 ℃.  This completes all starch gelatinization (which should be 0.98-0.99% complete at temperatures of 95-98 ℃)

Total baking time: 27.4 minutes

Very little more information was gleaned from comparing this article to another ThaiScience article that used neural networks to optimize the baking time and temperature.  ThaiScience is an online, mostly free database of engineering and science articles.  There are a number of bread-related articles I'd like to read. 

Notes to Myself

• Try the oregano loaf again, this time with a regular sourdough starter, and a slightly higher hydration. Would you combine this taste with walnuts, to get an extra-purplish loaf?  Or is this scent and flavour entirely claimed by pizza?
• I was astonished to learn that Onishi and his team believe that the yeast is quite active when the bread is initially put into the oven, just before they expire.  A lot of the oven spring comes from CO2 expansion caused by yeast in the minutes just before they are baked to smithereens. I had assumed otherwise.