VFR100 reworked assay

Another in a series of incredibly tedious posts guaranteed to scare away even the most dedicated of readers. To refresh your memory, this is to get an aggregate metric to characterize a combination of yeast, flour and any additive by the volume of the first rise.  Once analyzed it will be applied to see if this volume (VFR100) is predictive of final baked bread attributes.  See background of measurement in previous post.  I reworked my assay a bit.

1. add:
-salt as a 10% w/w solution
-vitamin C as a 0.1 g / mL solution
-qs to volume, 90 mL
-yeast 1/2 t (assuming bulk solid density for yeast is constant)
-soy oil delivered by pipette
-flour 150 g
2. knead 10 minutes via machine
3. scale a 100 gram piece and round it
4. let rise in cylinders like these, tall narrow to elongate final reading for precision, coated on inside with floured oil spray so the maximum height is marked after maximum rise falls, e.g., see typical final rise volume in image below.

click image for close up, left two are fast rise yeast and right has an extra 100 ppt shot of vitamin C
flour = Montana Sapphire unbleached white
C = vitamin C
yeast (charged at 2%):
salt for these 250 total dough runs, 2.5 g

fat (% v/w) yeast additive V of 100 g rise (mL)
0.0 soy
262 261 260 258 260
2.0 soy
308 313 263 280 301
2.0 soy
255 275 278 280 301
2.0 soy
C 1000 ppm
338 320 320 310 333
2.0 soy
275 280 274 275 295
2.0 soy
C 2000 ppm
321 326 338 345 360
Preceding runs anova=> R results
Significant effects:
-oil in the dough gives greater volume than no oil, consistent with literature for baked bread volume - may be worth evaluating more concentrations
-Big vitamin C effect but not so much between 1000 and 2000 ppm
-fast rise yeast bigger volume than active dry

*Additional values added after anova tabulated below
2.0 soy
C 1000 ppm, lecithin 1t
2.0 soy
lecithin, 1t
2.0 soy
Fleischmanns pizza
L-cysteine in yeast
4.0 soy

The sloppy discussion (by sloppy I mean I'll keep adding to it as I think about it) 

1. The volume effects, despite the unbalanced design, reflect a lot of what's observed in the literature. A low concentration of oil in lean dough is well-documented to result in bigger volume loaves and this is what's observed in the dough as well.

2. One of the biggest effects is the vitamin C (ascorbic acid)* added to dough.  Vit C addns. gave structurally sound, huge dough volume on rising.  As far as concentration, I killed it, 1000 ppm is a lot more than the more conventional 50 ppm seen in the literature.  However, I haven't yet found articles relating to the specific increases in volume of final baked breads as a function of vitamin C concentration.  In my hands, breads made with 1000 ppm (100 mg vitamin C per 100 g flour) have consistently crappy oven spring, it's a real bummer of a result.

3. Point 2 is leading me to believe the VFR100 just isn't predictive of the things I'm looking for in a final loaf.

4. This assay, to do with enough replicate runs is laborious, all the practice I did was interesting and useful.  I'm considering a way to make it a faster analysis.  That way I could crank many more effects and be able to see parameter interactions.  Maybe some pilot work and then take a look at reducing vitamin C/fat to try to figure out the interactions.

* Note: There are some who believe vitamin C and ascorbic acid are not the same.  They are, atom for atom, stereocenter for stereocenter, etc. etc. identical in every single way.

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