Flour quality lab data

Our grain and flour is tested numerous times between harvest and sale of the finished flour. Tests of the finished product are the most pertinent to our bakery customers. We make the most useful of the data from those tests available to customers at this website. Those who want more detailed information or data on lot numbers not listed here are encouraged to contact our director of technical services via email.  Just click on the link. 

 

These are the values we feel are the most useful for predicting flour performance

  • Protein
  • Moisture
  • Ash
  • Falling Number
  • Damaged Starch %

Alveograph

  • Constant Hydration
    • P/L
    • W
    • G
  • Adapted Hydration
    • T/A
    • Fb
    • Hyd 2200

Consistograph

  • TPrMax
  • Tolerance
  • Water Absorption

 

Where do these values come from and what do they mean?

Protein: This is simply the percent, by weight, of the flour that is protein, assuming for the sake of uniformity, 14% moisture in the flour. We use NIR (Near Infra-Red) analysis because it’s quick, easy, and accurate.

Moisture:
We use the same piece of NIR equipment to determine the moisture content of the flour. We often cross-check this with other NIR machines and with a balance oven.

Ash
refers to the mineral content of the flour and correlates to the degree of refinement. The higher the ash percentage, the more bran is left in the flour. Our unbleached flours range from 0.44% for some runs of Baker’s Patent to as high as 0.56% for some lots of unbleached all purpose flour. This value, like protein, assumes 14% flour moisture. Our stone-ground whole wheat and Golden Buffalo flour are considerably higher in ash.

Falling Number (FN): Now things start getting tricky. Falling number relates to the alpha amylase activity in the flour. A certain amount of enzyme activity is necessary for proper fermentation during the production of biologically-risen breads. Too much can cause problems (sticky dough, for one). The lower the FN, the more enzymatically active is the flour. Our all purpose, unbleached enriched flour has organic malted barley flour added to adjust the falling number downward to fall within a range considered “ideal.” All other Heartland flours are unmalted and their higher falling numbers reflect this. Bakers using unmalted flour should add their own malted barley flour for improved fermentation and crust color.

Damaged Starch: When wheat is milled into flour some of the starch granules in the endosperm are broken. This damaged starch absorbs much more water than the undamaged granules. If too little damaged starch is in the flour, it will be difficult to mix normal to high-hydration doughs. If there is too much, the flour will exhibit high absorption, but the loaf may flatten at the end of proofing as the excess water is released. In between these extremes, as damaged starch increases, absorption will go up, but at the expense of extensibility and overall dough strength.

This is well demonstrated in Alveograph studies. The same wheat blend, milled with different mill settings or different tempering times before milling, will result in different levels of damaged starch. The resulting flour will show absorption increasing as starch damage increases. The Alveograph "P" value will also rise, and the "L" will shorten. Interestingly, there is a range of "P/L" in which the "W" (strength) will reach a peak level, then it will drop off. "P" does not increase as "L" shortens, thus resulting in lower overall strength, "W."

Even within an acceptable range of damaged starch, performance is influenced by even seemingly small differences. Too little damaged starch will result in overly extensible doughs, with insufficient elasticity. Too much and the extensibility may become excessive.

Alveograph:  While numerous values can be derived from the results of this test, those that we are most interested in are strength and the relationship between the extensibility and the tenacity of a dough made with the flour, water, and salt.  The strength is expressed as “W” in a Constant Hydration (CH) Alveograph and “Fb” in an Adapted Hydration (AH) Alveograph.   “P/L” is the value that expresses the balance between extensibility and tenacity in the CH test; T/A in the AH alveograph.  Constant Hydration Alveographs always use 50% hydration (250 grams flour, 125g of water-salt solution).  The percent hydration used in an Adapted Hydration Alveograph is calculated to achieve a dough of a pre-determined consistency. 

We believe that the relationship between the curve configuration (P/L or T/A) and the strength are important to consider.  A ratio between 0.70 and 1.0 seems to provide a good balance of tenacity and extensibility.  Some high absorption flours milled from High Plains winter wheat will have very good strength (~400), but appear to be lacking in extensibility in the CH Alveograph, exhibiting ratios from 1.2 to 1.5.  By simply adjusting the water used to form the test dough , the ratio drops to within the ideal range and the strength remains well over 300. (This computation is a function of the AH Consistograph, which allows the technician to determine the amount of water required to achieve a predetermined consistency.)

This addition (or subtraction) of water to a dough in the laboratory is analogous to a baker adjusting the amount of water in the mixer bowl to achieve the ideal dough consistency.  Performing both the CH and the AH versions of the Alveograph (or AH at two different hydration levels) allows us to see how dough made from the flour responds to different hydration levels.  If, with increased hydration, the strength remains sufficiently high and the curve ratio (T/A) is in the preferred range, we’re confident that the flour will perform well in the care of the skilled bakers who use our flour.

Consistograph:  The Consistograph is used in conjunction with the AH Alveograph.  It gives us values that measure flour/dough properties similar to properties measured by the more commonly used Farinograph.  TPrMax is the time in seconds to develop the dough to that degree and Tol (tolerance) is the seconds of mixing tolerance the dough exhibits.  PrMax Target indicates the consistency of dough we used for the test.  The higher the number, the more resistance it offers the mixer.  Wa (14% mb) is the absorption of the flour, calculated by the Chopin software to correspond to the absorption from a Farinograph.  This is not the hydration level recommended for bakery use.  Comparing this number across lots may help the baker in determining how to adjust water for new shipments of flour.  Because of differences in equipment and protocol, other numbers (tolerance, etc.) cannot be compared directly to Farinograph results.  They are best used in comparing different lots of flour that have been subjected to the same test.