Detailed Lot Information
Understanding Flour Analysis: How to Harness the Advantages of Information
We at Cook Natural Products feel strongly that varietal grain selection, identity-preservation and full disclosure of laboratory analysis are the factors that allow us to provide flour especially suited to bakers for whom quality is a primary concern. Our job is to make sure that appropriate grain is grown, segregated, (blended if needed), milled properly and transported efficiently. The manner in which we manage that process is designed to provide not only consistency, but specific quality. Identifying desirable characteristics, and finding the grain that exhibits those qualities is an ongoing process for us. Please understand that no matter how well we do our job, no two lots of flour are identical. The only way to predict the effects of flour variations on your products, is to learn how to read flour analysis sheets.
Now that we are providing flour analysis for every lot of flour that we sell, we have realized it is time to help educate bakers about exactly what those analyses mean. Brewers, and wine-makers have numerous advanced sources of objective data concerning every aspect of what they do. They also have the references and educational resources to allow them to understand that information. Cook Natural Products hopes to help bakers by improving their flour literacy.
Below are some helpful details of the typical points of our analysis sheets:
The mill date indicates just that: the actual date that the flour was milled. It is important for the baker to know the age of the flour on the floor. White flour is thought to be “mature” three to four weeks after milling. During that time, certain biochemical and oxidative changes occur that result in flour with optimal baking characteristics. If stored in a dry, clean area at 70-80° F. shelf-life is easily 24 months. Because of the high lipid and lipase concentration in whole-grain flour, we recommend use within four to six weeks of milling in all whole-wheat and whole rye.
The lot number always printed on the bag is used as the reference for a particular lot/mill-run. Cook Natural Products lists all flour specifications by the lot number. In most cases the lot numbers refer in some way to either the mill, or pack-date.
Indicates the certifying agency for the flour.
Wheat is generally classified by describing three different parameters: kernel hardness, kernel color, and growing condition. The four main categories are: hard red spring (HRS), hard red winter (HRW), soft red winter (SRW), and winter and spring white wheats.
Indicates the name of the specific wheat variety. Cook Natural Products is always gathering data and feedback so that we can help our farmers make better choices about the wheat varieties that they plant. We believe that being a conduit to communication between the growers and end-users is integral to our goal of providing superior flour to the baker.
Just about all of Cook Natural Products’ growers farm wheat under dryland conditions. This means that the grower does no irrigation, and is subject to the vagaries of nature: drought, flooding, hail etc.. Irrigated wheat farming is usually dictated by climate. This is a very expensive, and energy intensive method.
This figure is the protein content of the wheat before milling. In general white flour will have a protein content about one percent lower than that of the wheat. This figure will change, depending on milling technique and extraction. This is the main parameter for judging wheat quality in the conventional grain market. Cook Natural Products takes the extra step of analyzing the “protein quality” by running an alveograph test before milling.
The moisture of wheat is primarily of interest to the farmers and millers. The price, storage-stability, tempering time and milling characteristics are all affected by the wheat’s moisture content.
Tempering is the process of adjusting the moisture content of wheat. At the mill, after the wheat is cleaned of dirt, foreign seeds, chaff etc., the wheat is tempered. The wheat is moistened and left in rotating drums until the moisture content is 17-19 %. Sometimes the wheat is heated/steamed to hasten tempering. Tempering optimizes the separation of the branny covering and germ from the endosperm. Tempering also makes the endosperm less liable to starch damage.
Traditionally flour protein has been the main parameter used to judge flour quality and strength. Today we know that not all wheat protein is created alike. Wheat albumen, (protein) is composed of four types of protein: gliadin, glutenin, albumin and globulin. Gliadin and glutenin comprise roughly 85% of the albumen, and are the gluten-forming components. Albumin and globulin are water soluble, and thus don’t add to the strength of the flour. The percentage of protein, (albumen) only tells us the amount of protein, and is only a hint as to the real character of the flour. This figure does not tell us anything about the type, or quality of protein. The alveograph test gives us more valuable information about the “quality” of the protein; and thus how it will perform in the bakery.
The level of moisture in flour is important mainly for the issue of storage. When the moisture level exceeds 15 % the shelf life of the flour is greatly reduced. Generally, the moisture will be 12-14%, which when stored in appropriate conditions, (relatively cool, dry and aerated) allows for plenty of shelf life.
The ash content of the flour is determined by incinerating a sample of flour. The minerals naturally present in the flour do not burn and remain as ash. The weight of the ash is then compare to the original sample. The ash content tells us something about the extraction of the flour. In the endosperm of the wheat kernel, the mineral content increases from the center outwards. The area of the endosperm nearest the aleuron and bran layers has the highest mineral content. Higher ash contents indicate higher extraction. Cook Natural Products aims for an ash content of about .55% in our white flours.
The falling number test determines the alpha-amylase activity of a flour sample. The test entails heating measured amounts of water and flour in a special tube. The tube is placed in a boiling water bath and stirred with a plunger until the sample is gelatinized. Then the plunger is placed on the surface of the sample, and the time that it takes the plunger to sink to the bottom of the tube is recorded. Depending on the alpha-amylase activity, the degradation of the starch paste will vary. The higher the alpha-amylase activity, the lower the number, and vice versa. Typically the falling number has to be adjusted through the addition of diastatic malt, or fungal amylase. Such adjustments are usually done at the mill, along with the enrichment package. Our organic flours are un-malted, so they have high falling numbers, generally in excess of four hundred. Malted bread flours have falling numbers of: 250-290. Generally the baker will find that fermentation progresses more rapidly as falling numbers become lower.
The “Brabender Farinograph” is one of the most common flour testing machines in use today. The farinograph produces a graph that represents the force required to turn two mixing arms in a small mixing chamber with dough at an adjusted hydration. On the graph each vertical line represents thirty seconds. The horizontal axis spans 0-1,000 brabender units; each line marking 20 BU, (i.e. force/resistance). The key points of record on the graph are as follows:
Indicates the interval between zero minutes and the point at which the top of the curve first intersects the 500 B.U. line.
The time from zero minutes, to the point when the top of the curve leaves the 500 B.U. line.
The peak is the time interval between zero minutes and when the curve indicates maximum resistance. In general lower peak times correlate with lower flour protein and absorption.
The difference between departure time and arrival time.
Dough hydration is adjusted so that the peak of the graph is centered on 500 BU, resulting in a predetermined dough consistency. The absorption indicated is the adjusted hydration. When looking at farinograph absorption it is important to realize that this is not an absolute value. The greatest value can be had from comparing absorption values from lot to lot, and making adjustments proportionately.
Mixing tolerance index is the difference in BU, from the top of the curve at the peak to the top of the curve measured at five minutes after the peak. Higher MTI numbers indicate greater mixing tolerance.
TMD (Twenty Minute Drop)
Represents the difference in B.U. from the 500 B.U. line to the center of the curve measured at 20 minutes from the addition of the water.
Inherent characteristics of the wheat, along with the physical effects of milling determine the level of starch damage. The process of wheat milling damages a portion of the starch granules. This tendency is amplified as the hardness of the wheat increases. Because of this, starch damage is of particular concern here in North America. Starch damage increases the amount of fermentable carbohydrate as well as the absorption of the flour. Normally starch granules absorb one-third their weight in water, when damaged that increases to 2-3 times their weight. Damaged starch granules are very susceptible to attack by alpha-amylase enzymes. The combination of high levels of fermentable carbohydrate, and water, (and thus rapid enzymatic activity) make conditions optimal for more active fermentation as the damaged starch levels increase. Also, though flour with high starch damage figures absorbs a lot of water, once the amylase enzymes do their work, the dough becomes slack. Balance, as always, is key. Too much starch damage, and the dough tends to be slack and over-fermented; too little and the fermentation stalls after the immediately available sugars are consumed. One should expect to see starch damage at 6-9% for winter wheat’s, and 7-10% for spring. Damaged starch significantly affects both Farinograph water absorption, and dough extensibility and resistance (Alveograph).
Alveograph CH (Constanct Hydration)
Produced by Chopin, the Alveograph is an instrument that gives valuable rheological information about a dough sample by measuring the pressures attained during the inflation of a dough sample into a bubble. Because the test expands a dough sample in a biaxial plane, similar to the way dough cells expand in actual bread dough, this test is highly regarded.
Also known as, “the deformation energy”, the W represents the force required to inflate the dough bubble until rupture. Literally the W is the area under the curve on the graph, multiplied by a factor of 6.54. This value generally indicates the overall baking strength of the sample. The water absorption is generally thought to increase as the W increases. Loaf volume is also thought to increase as the W value rises. Bread flour W values tend to be 200+, with number up to 400 being especially appropriate for dough undergoing long fermentation times. Along with the numerical figures, it is important to actually see the drawing of the curve. Using the drawing along with the other Alveograph values, gives the baker the greatest chance in predicting flour performance. There is great value in compiling drawings and data along with real-world impressions of flour over time. Only in this way can rheological testing data be put to its greatest use.
Also known as the overpressure, the P is the maximum height (h) in mm. on the alveogram multiplied by a factor of 1.1. This figure represents the viscosity, tenacity, or even strength of the sample. The AACC defines overpressure P as an indicator of dough resistance to deformation. As P rises, so does the resistance. Some also believe that P can be taken as a measure of the hydrating capacity of the sample. Because the maximum height is effected by the type and thickness of the dough, some researcher believe that the ratio of the height of the curve at the bubble volume of 100 ml (P100) to the height of the maximum (Pmax) provides a better correlation with potential loaf volume.
Hamed Faridi and Vladimir F. Rasper write in, “The Alveograph Handbook”: “The average abscissa to rupture, L, is the average length, in millimeters, of the quintuplet curves from the point where the dough bubble starts to inflate to the point where the bubble bursts and the pressure drops suddenly. Unlike overpressure P, the meaning of this index seems to be unambiguous. L is commonly used as a measure of dough extensibility.”
This ratio is thought to indicate general gluten performance. In other words the balance between dough elasticity and plasticity. In general values of 0.40-0.90 are thought to be appropriate for bread baking. As the number rises, there will be a certain point where the dough will be too elastic/resistant, yielding a less developed loaf with compact crumb. Conversely, when very low P/L values indicate a dough that is too extensible. There is no absolute perfect value. Finding a balanced value that is appropriate for the application is key.
The B-Value figure gives information about the color of flour. Color definitely determines the crumb color of bread; but also gives clues about: flour grade, bleaching and granularity. Cook Natural Products utilizes no chemical bleaching methods. Because of this, and our milling methods, customers can expect to find our flour to have a distinct creamy/yellowish hue.