I’ll be honest, I don’t understand the buzz around pumpkin spice. I know it’s everywhere – coffee, donuts, cheesecake and scented candles – but what is it really?

“I don’t remember pumpkin having a scent,” I wonder aloud as my wife fires up the pumpkin spice-scented candle.

“It’s not pumpkin,” my wife explains with a hint of exasperation, knowing where these discussions always lead. “It’s pumpkin spice.”

“So it’s just all of the spice that makes pumpkins edible?”

“Yes,” my wife replies, “That’s exactly it!” She places an exclamation mark at the end of her statement, hoping the discussion is over.

“So why don’t they just call it a cinnamon, ginger and nutmeg candle?”

“It wouldn’t fit on the label!” I see the exclamation point this time.

What is the difference between a scent and an odor? A scent is intentional; an odor just kind of happens. A scent is pleasing; an odor is less pleasing. A scent is typically expensive, and an odor is expensive to cover.

As with many eye-opening experiences, I was first acquainted with scented candles in college. Before the male of the human species is domesticated by the female of the human species, men smell really bad. Ladies, most of you just glanced across the room at that gas bag husband of yours, but trust me when I say, it was worse before you met him. This is where scented candles come in.

Flatulence is one of the most pungent odors that mammals create. When the microbes in the gastrointestinal tract process the food or feed that is eaten, the microbes produce volatile fatty acids, which are good for you, and methane, which must go somewhere. This gaseous methane will work its way through the intestines, through the colon and out the backdoor.

Methane gases are flammable. That is the genius of a scented candle. The open flame will burn off the methane, and this odor is replaced with a more pleasing scent. That is why I affectionately refer to these modern miracles as flatulence candles.

Production agriculture is well known for its scents and odors. A powerful scent for me is the aroma of fresh-cut hay. The smell of burning hair elicits the community found at a branding. Have you heard our equestrian friends claim that the smell of a barn is intoxicating? That barn smell evokes the memories from working around horses. But the smell of a barn is horse manure, urine and sweat. Most will add the smell of leather to make it less weird, but leather has the same smell as pumpkin … it’s more pungent with the spice.

In reality, the smells generated by production agriculture fall into the odor category. We use phrases like “smell our money,” but our more urban neighbors hear “put up with the smell while we make money.” Should we in production agriculture mitigate the odors emanating from our businesses?

Can we turn that tired old phrase “smell our money” into reality? Farmers and dairies right now are converting their odors into fuel. Anaerobic digesters convert manure, food waste and other organic wastes into methane. This biogas is used to generate electricity, to fuel machinery and as a heat source. These flammable gases are a byproduct from microbial action. With these systems, the odor of manure and other waste becomes the scent of energy production.

Imagine a production system where potato waste from a processing plant is fermented into ethanol; the byproduct from ethanol is a predigested feed for animals. Then the manure from the animals is fermented anaerobically into biogas, and the final waste can be applied to potato fields as a bioavailable, nutrient-dense fertilizer. The odors in this production system can be captured and used in energy production. Every part of this system is currently available but not integrated into a complete system.

These biogas systems are more common in Europe, where government subsidies lower the capital intense upfront costs. The European systems are small and create enough biogas to power electric generators and methane tractors on the farm.

These biogas plants are sprouting up around dairies in southern Idaho. As the technology improves, we should expect biogas to scale up. Instead of the European small-scale model that partially powers the farm, someday large Idaho dairies could produce enough biogas to add base power to the grid. Could you imagine a world where the odor of cow manure, food waste and other agricultural wastes become the scent of energy?

The scents of fall are everywhere. I sip on my pumpkin spice coffee while nibbling on a pumpkin spice donut. A pumpkin spice flatulence candle crackles and burns in the ambient background. I find comfort in knowing that the problem of agricultural odors may someday have a profitable solution. If only we could find a cinnamon, ginger and nutmeg solution to gas bag husbands, then the ultimate problem of odors will be solved. This is the promise of pumpkin spice.