9.03.2011

On the Development of a Predictive Metric for Bread Loaf Volume, the VFR100

It is generally recognized among food scientists that greater volume in a baked bread is associated with favorable properties like tenderness, desirable mouthfeel and reduced rate of staling.*

Personally I like bigger volumes in my breads and the pursuit of achieving that continues today for my white and wheat breads.  Bigger volumes are most commonly obtained with a small fraction of fat, ca. 3% w/w percentage of the grain bill.*  In addition to the oil, a functional ingredient, I have also noticed the brand and type of yeast have a significant impact on the dough (structure during rise, tackiness, rate of rise, etc.).  Further complicating this is my unsubstantiated loyalty to a particular flour.

Evaluating the effect of various combinations of fat, yeast and flour on the final baked loaf is a daunting task.  After the ingredients are mixed, many factors, e.g.,  the number of rises, the proof (final rise), docking, baking method, baking sheet, oven humidification method, etc. can have a significant effect on the results.  In an attempt to support these preferences with something more quantitative, I'd like to find a reproducible and relatively fast assay for these ingredients that correlates with a final baked product.

My hypothesis: Given a selection of dough ingredients, the volume of the first rise will lead to a predictable outcome of the final baked loaf of bread, presumably the greater the volume of the first rise, the better the loaf.  I'd like to stop at the first rise because I think it's the optimal point of intervention.  All the ingredients are included and working. One serious potential flaw is there is no way to evaluate the effect of oven spring.  This volume will be called Volume of First Rise of a 100 grams sample, the VFR100

Method for obtaining the VFR100
1. make a dough comprised of flour (150 g - not defatted), salt (2.5 g), water (90 g), fat (variable), yeast  (1 t, 3 g).
2. machine knead for 10 minutes using an Oster xxxx on the simple white bread cycle
3. scale 100 g from this and add it to a graduated cylinder
4. measure maximum final volume of rise - the meniscus of the dough adheres to the graduated side of the cylinder at the highest volume using this apparatus

The data collection phase will take a long time.  I'll populate the table as results become available.  Feel free to suggest additional parameters in the comments.  I can't promise I'll include them in the testing, but I'd love the input. 
After this data collection, I'll be trying a full preparation of a baguette using a few of the combinations, good and bad candidate mixtures.

data collection underway 


Table Abbreviations
ap, all purpose
b, bulk
C, ascorbic acid
f, fast
F, Fleischmann's
GM, gold medal
MT, Montana Sapphire
RS, Red Star
ubw, unbleached white

http://onlinelibrary.wiley.com/doi/10.1111/j.1745-4530.2008.00282.x/abstract (this paper and references cited therein provide a lot of the background on bread loaf volume and functional fats)

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