Yeast's nutritional benefits
December 13, 2016
by Laurie Gorton
Yeast can provide more functions than just helping dough rise.
The deck is stacked against baked foods with highly colored crusts or made by high-temperature processes. Heat in excess of 120°C (248°F) can trigger formation of acrylamides from the amino acid asparagine present in many proteins. Acrylamide is a World Health Organization Group IIA carcinogen shown to be mutagenic and neurotoxic in a variety of laboratory animal studies. It occurs in common foods such as bread, toast, potato chips, fries, cereals and coffee.
Renaissance Ingredients isolated a strain of bakers yeast with an accelerated natural ability to consume asparagine. The acrylamide-reducing (AR) yeast has been found to cut acrylamide by 80% in bread and up to 95% in other foods, according to tests described by the company’s president, Matthew Dahabieh, PhD. “These results confirm the efficacy, simplicity and seamlessness of using our AR yeast in bread and toast,” he said. “In most cases, the acrylamide content of toasted bread made with it is less than that of untoasted bread made with conventional bakers yeast.”
The AR yeast provides all the leavening function of conventional bakers yeast. Last year, Renaissance filed for a US patent on its AR yeast and received provisional coverage. Earlier this year, the Food and Drug Administration (FDA) issued a “no questions” letter when the company submitted a Generally Recognized As Safe petition.
“We are now looking to demonstrate this efficacy in pilot-scale trials by working closely with additional interested industry partners,” Dr. Dahabieh said.
Now a few years old, vitamin-D enriched yeast promises a unique answer to the persistent inadequate intake among Americans of this vital nutrient, often called “the sunshine vitamin.” This idea springs from the fact that S. cerevisiae naturally produces ergosterol, the precursor of vitamin D, and is a base for manufacturing vitamin D dietary supplements.
The bakers yeast division of Lallemand turned the idea into Vita D yeast to enable natural fortification of grain-based foods with the essential vitamin. “Consumers are more aware of vitamin D benefits and risk of deficiency,” Mr. Edwards said. FDA recognized vitamin D earlier this year by allowing it to be called out in the revised Nutrition Facts Panel.
In a proprietary process, the company exposes its bakers yeast to ultraviolet light, naturally transforming the sterols present in yeast into vitamin D. No chemicals or synthetic additives are involved. Thus, Vita D yeast products are non-fortified and vegetarian sources of vitamin D. The yeast’s leavening and flavor contributions remain intact. Studies in bread indicate the vitamin was stable to heat and oxidation. Lallemand has equipped all of its North American plants to use the process for all of its yeasts (fresh cream, fresh compressed and instant dried yeast).
Acting on a petition filed by Lallemand, FDA increased the amount of vitamin D allowed in bread and baked goods to 400 IU per 100 g of product, up from 90 IU, when making bread with vitamin-enhanced bakers yeast. This allows bakers to claim their products as “high,” “rich in” or “excellent” sources of vitamin D.“But you can only claim that amount if you use yeast with vitamin D,” Mr. Edwards emphasized. You can’t make the claim by fortifying your product separately with vitamin D.” Levels of the vitamin in these yeasts is optimized for conventional bakery use to allow a “good” source claim.