There's nothing like the smell of baking bread to stir memories of warmth and comfort.
Well, forget that. As it turns out, that pleasant scent threatens the environment - the chemical that wafts the delectable essence across neighborhoods near large bakeries may help create smog.Bread factories around the country may soon be called upon to limit their odorous emissions as states work to meet federal clean air requirements.
That means no more bread smell. No more warm, comforting factory aroma that harks back to Grandma's kitchen.
"You drive down the highway and you hope the smell will be there," said Phyllis Davidson, a customer at the second-day bake shop outside the Wonder Bread factory in Natick, which may have to install equipment that would do away with the aroma.
"It's like waking up to the smell of coffee brewing or bacon cooking. It's homey," Davidson said.
When bread reaches 174 degrees Fahrenheit - when it's baked to perfection - it emits ethanol as a gas.
Massachusetts is one of 33 states that either have or are drafting ethanol emissions regulations for large bakery ovens.
Ethanol is a volatile organic compound that contributes to ozone buildup close to the ground. The 1990 Clean Air Act gives states until November to submit plans for reducing ground-level ozone.
By itself, ethanol is harmless alcohol, said Anne Giesecke of the American Bakers Association: "It's the same as what people would exhale in a bar on Saturday night."
But when ethanol hits sunlight, it breaks down into its basic components, including oxygen, and forms ozone.
High in the atmosphere, the thinning ozone layer allows dangerous ultraviolet radiation to seep through to Earth. Close to the ground, too much ozone means smog.
Environmental Protection Agency officials emphasize that ethanol regulations don't apply to small neighborhood bakeries, only to large bakeries with the potential to release more than 50 tons of ethanol annually.
But tell that to the auto mechanics at Sears in Natick - connoisseurs of the odors that waft into the garage from the Wonder Bread factory across the street.
Some are gourmets: After 30 years, Tony Freitas still raves about the way that cinnamon smell warms the spirit on bitter winter mornings.
Others are gourmands: "See all of us who look like this?" said mechanic C.J. Deberadinas, grabbing and shaking his spare tire of flab. "We all like the bread smell."