Protein Alone Does Not Predict Soft White Wheat End-Quality Performance

There is an easily understood expression in English that “you cannot judge a book by its cover.” Applied to the new 2021/22 U.S. soft white wheat crop that is good advice for the world’s flour millers and wheat food producers.

The persistent Pacific Northwest (PNW) drought is expected to lower yields and push 2021/22 SW protein levels higher than average. As USW Bakery Consultant Roy Chung says, however, protein level alone does not say everything about soft white end-quality performance.

Instead, U.S. Wheat Associates (USW) is helping flour millers learn that testing for Solvent Retention Capacity (SRC) is the most effective and valuable method for predicting the true performance characteristics of flour for biscuits (cookies) and crackers.

The SRC method, approved by the American Association of Cereal Chemists (56-11.02), examines the characteristics of glutenin, gliadin and arabinoxylan and the level of starch damage in flour. These values describe the flour’s ability to absorb water during the mixing process and its ability to retain or release that water during and after the baking process, among several other performance characteristics.

The combined pattern of the four component SRC values establishes a practical flour quality profile useful for predicting functionality, giving the miller and baker a ‘fingerprint’ of U.S. soft white (SW) and soft red winter (SRW) wheat flour end-quality performance.

“While rheological analysis tools measure the combined effect of the components in flour, individual component functionality, measured by SRC, gives a better picture of whether you are going to get the desirable performance from the flour for the product you want to make,” Chung told a large audience of millers and bakers in a USW webinar on SRC in June 2021.

With a more complete understanding of the functional value of wheat proteins, carbohydrates and other properties, flour milling quality control managers will have additional information to evaluate the characteristics more accurately of U.S. soft white wheat and Western White (a blend of SW and a minimum 10% white club) this year compared to competing supplies.

“In addition, more wheat food manufacturers are looking for ways to ‘clean up’ their ingredient labels,” said USW Regional Technical Director Peter Lloyd. “USW can show SRC results to millers and bakers that prove flours from U.S. soft white wheat and SRW wheat can make beautiful end products without adding any ‘magic powder’ like enzymes that have to be added to medium protein wheat flour to make weak gluten products.”