In their experiments, Peterson and his research group took a batch of rolled oats and divided it into two samples. They boosted the level of polyphenols in one of the samples by an amount that can be found in nature and then roasted both samples. The sample that had the added polyphenols developed a lower level of Maillard-type aroma compounds as measured by gas chromatography and a panel of trained human sniffers.
The Penn State group's analyses show that the polyphenols inhibit the Maillard reaction by tying up or quenching some of the sugars and other transient reaction products the process needs to proceed.
Peterson explains that the Maillard reaction not only produces desirable changes, such as a golden brown color and toasty aroma, but also can sometimes cause off-flavors or stale odors. The reaction not only proceeds during roasting or baking but also during storing. The new Penn State results suggest that controlling the levels of polyphenols, which are found naturally in all food plants, might prevent undesirable results of the Maillard reaction.
In addition, the Penn State scientist points out that the Maillard reaction also occurs in the human body as part of the aging process, in tanning, hardening of the arteries, and diabetes as well as other diseases.
"The polyphenols' ability to quench sugars and inhibit the Maillard reaction may have positive implications for health besides improving the quality of food products," he says.