It’s that time of year …” In December, this phrase prompts visions of winter festivities; a few months later, it’s stressed accountants with an April 15th deadline. And now it’s bakers, anxious to know how new harvest flours might impact the formulations they just spent all year perfecting.
Unlike most commercially produced foods, grainbased foods often require an annual formulation review. This is because their primary ingredient — wheat flour — frequently undergoes compositional changes with each harvest.
“Bakers need to be aware of when their wheat flour supplier transitions from the previous year’s crop to the new season’s crop because flour compositions can vary, and this impacts performance in the finished product,” said Mike Fassezke, vice-president of the flour milling division of Star of the West Milling Co., Frankenmuth, MI.
Brian Walker, technical services manager, Horizon Milling LLC, an affiliate of Cargill, Inc., Minneapolis, MN, added, “From my experience, the bakers who stay in touch with their flour suppliers are the least likely to get surprised because they are prepared to do the things necessary in the bakery to optimize the changes that will occur. Also, keep in mind, there are rare occasions that a crop transition will go exactly the same from year to year.”
A LOOK AT THE CROPS. To better understand how wheat flours can vary in composition, it is necessary to understand wheat crops. There are eight classes of wheat: durum, hard red spring, hard red winter, soft red winter, hard white, soft white, unclassed and mixed. Mixed wheat is the designation for grain shipments that contain less than 90% of one wheat class and more than 10% of one or more other classes. Unclassed wheat is the designation for any variety that cannot be classed under criteria of the other standards.
Wheat is grown across the US as well as Canada and Mexico, with the kind and quantity of wheat varying greatly region to region. Differences in topography, soils and climate make this variety possible.
Bakers seldom make bread from durum wheat because it is the hardest of all wheat classes and has very high protein content (12 to 15%). Grown primarily in the North Central and Southwest regions, durum wheat is mostly used in pasta manufacturing; however, it has successfully formulated some Mediterranean-style breads.
“Winter wheats are the first to be harvested every season because these crops were planted in the fall. They germinate and then remain dormant throughout the winter,” Mr. Fassezke said.
Soft red winter is grown in the eastern third of the country. It is a high-yielding, low-protein (8.5 to 10.5%) wheat with weak gluten, rendering it applicable for pastries, cakes, cookies, crackers, pretzels, flatbreads and for blending flours. Hard red winter, on the other hand, has a medium- to high-protein content (10 to 13%), with medium gluten content that is considered mellow gluten. Hard red winter wheat is grown in the Great Plains and California and is considered a versatile bread wheat.
“There’s a misconception in the industry that there is a single harvest for wheat, when in fact it is more like three,” said Michael Pate, vice-president, corporate quality assurance, Bay State Milling, Quincy, MA. “Soft winter wheat is harvested as early as mid-May, with hard winter following in early June. The other wheats, which are planted in the spring, are not harvested until the latter part of August.”
Hard red spring grows in the North Central region. It has high protein (12 to 15%), strong gluten and high water absorption properties, ideally suited to use in pan and hearth breads, rolls, croissants, bagels, hamburger buns and pizza crust.
Soft white is grown primarily in the Pacific Northwest region. Like soft red winter, it is low in protein (8.5 to 10.5%) and has a low moisture content, making it most appropriate for flatbreads, cakes, biscuits, pastries, crackers and snack foods.
Hard white is the newest class of US wheat and is grown in California, Colorado, Idaho, Kansas, Montana, Nebraska, Oklahoma and Washington. It has medium to high protein content (10 to 14%) and is used mostly in pan and flatbreads.
“Bakers tend to stick with the same class of flour from year to year; however, in some years, climatic issues prevent grains from certain geographies from being milled into flour,” Mr. Pate explained. “These grains will go into feed channels.”
This is definitely a situation when a baker will need to adjust product formulations because a different wheat class will need to be substituted for what was previously being used.
“We (millers) want to make the transition from harvest to harvest as transparent as possible,” Mr. Pate said. “However, there are so many uncontrollable environmental variables possibly impacting the quality and performance of wheat that this can be challenging. Oftentimes, different classes of wheat will need to be blended to meet the specifications of the end user such as the baker.”
ENSURING GRAIN QUALITY. The Federal Grain Inspection Service (FGIS), an agency of the US Department of Agriculture (USDA), administers a nationwide system for officially inspecting and weighing grain, as well as designing tests that measure relevant wheat quality attributes. The market needs accurate and reliable test methods to differentiate the intrinsic functional qualities of wheat that impact the end products made from it.
A number of basic tests are run on flour. This includes determination of protein content, as well as the types of protein, dough mixing characteristics and baking attributes.
“We collect samples to evaluate protein and rheology parameters and, most important, to perform the bake test and other end-use product testing,” Mr. Walker said. “Results are generally compared to the flour product shipped from the old crop so the miller and baker can determine the best adjustments necessary to maintain quality baked foods for the consumer.”
Mr. Pate added, “Once the flour miller has run these tests on the new harvest flour, it is important that the baker collaborate with the miller to determine if a transition protocol is necessary. This would be a blend of flours that would make the full transition from last year’s harvest to the new harvest easier.
“Some commercial bakers, as soon as they find out that the new harvest flour is available, want to make an immediate complete switchover,” he continued. “I do not recommend that. A slow transition through blending flours is a better approach to ensure a quality, consistent finished product.”
Mr. Walker explained, “A gradual transition from old stock to new stock also allows time for the new wheat to age and go through the transition known as the ‘sweat.’ ” But he added, “In years when the old supply is tight, the transition is more abrupt. We could go from 100% old crop to 100% new overnight. This is not ideal, but some years, it is the best, if not the only, answer. Communication is crucial to minimize quality issues.”
And communication is ongoing. “Once bakers have made the transition, there’s another caveat: There might not be a sufficient supply of the new harvest flour for the entire year,” Mr. Pate observed. “This is why communication between miller and baker must go on all year. We want to keep functional and cost issues at a minimum.”
THE SITUATION FOR 2010. “So far, so good” described the 2010 harvest at print time. “All three harvests are looking good at this point in time,” Mr. Pate observed. “But one or two bad storms could damage a crop. Anything could happen.”
Mr. Fassezke explained that the single biggest issue affecting crop quality is weather. “For example, the grain can be infected by disease, which is primarily due to weather being too wet.” There’s nothing a grower can do to stop the rain.
“New crop wheat growing conditions are monitored by several entities,” Mr. Walker noted. “USDA does a good job of identifying the effects of weather and the potential impact on yields. These conditions are reported from ‘poor’ to ‘excellent’ and give a percentage breakdown.
“Companies also send crop scouts looking for disease pressure, weather damage and moisture conditions,” he continued. “As time goes on, there is conventional wisdom about whether protein will be high or low, but the performance quality is yet to be determined. Protein comes from stress in the field and can be a good thing, but disease also provides stress, and that could be a negative.
“Ultimately, wheat quality isn’t determined until it is cut and put into the bin,” Mr. Walker explained. Harvest conditions can be just as crucial as the entire growing season to determine the crop’s quality.
“When wheat is ripe and ready for harvest, if it is too wet, sprout damage can occur,” Mr. Fassezke added.
Sprout damage is the undesirable germination of wheat kernels that occurs on mature, unharvested wheat when wet field conditions persist just prior to and during the harvest. Mature wheat that has been cut and left lying in the field prior to threshing is particularly vulnerable to sprout damage. Germination dramatically increases the natural presence of alpha-amylase, an enzyme that converts starch to sugar and negatively impacts starch quality in the flour.
The Falling Number test measures the presence of this enzyme. A high Falling Number reading (reported as the number of seconds it takes for the instrument’s stirring rod to descend through a heated flour-and-water solution) indicates that the wheat is sound and satisfactory for most baking processes. A low Falling Number reveals that harmful sprouting has occurred and is suggestive of reduced baking quality. In bread, too much alpha-amylase activity will cause wet sticky bread crumb with large voids in the loaf, while too little causes dry crumbly bread crumb and high loaf density.
There’s also the issue of the wheat being green, or very fresh. It needs time to stabilize after being harvested. “We transition many of our mills to new crop in the heat of the summer,” Mr. Walker explained. “New wheat is a little green in terms of its optimum milling quality. The miller looks at several factors on the mill when dealing with new raw materials. How hard is it physically? How much conditioning is needed for ideal tempering? How hard do we grind? Does the mill flow well with the new wheat? Is the capacity the same or not? Often, adjustments are required, and it takes time. The hot weather also impacts how the wheat bolts (sifts) and can throw a change or two into its milling and baking performance.
“In the end, the business conditions facing the baker often drive the give-and-take of transitioning from old harvest to new harvest flour,” Mr. Walker continued. “Some bakers want to just get it done and get it behind them because they have other things to do. Others are more protective and cautious about the potential impact on the brand. The bottom line is, having a strict rule setting one extreme or another never guarantees flawless results. The important keys are patience, communication and flexibility by all parties. Wheat is like no other cereal grain, and no two years are exactly the same.”