- [Narrator] With more than 430 breweries across North Carolina, the beer industry contributes almost $13 billion to the state's economy.

As the industry grows, brewers work to reduce their environmental impact that starts at places like Perry Farms in Roseville in Northern Wake County.

- My name is Tim Kuhls.

I am Head Barley Grower here at Perry Farms.

And it's a self-proclaimed title, but basically what I do here is help out with the malting grains that we grow for brewing and distilling.

- [Narrator] Beer begins with grain, and lots of it.

Every acre planted requires two tons of seed.

- The reason why barley is so popular with brewing is because it's really the only grain that comes prepackaged with all the enzymes that are required in the brewing and fermentation process.

- [Narrator] In early fall, Kuhls planted 52 acres of winter barley and seasonal rotation with tobacco and soybeans.

In May, he'll harvest the barley and sell it to a local malt house.

There, the barley will germinate before the malt house cleans the grain and ships it to regional breweries.

- And so the tie for us to the brewery is that malt house concept.

And recently, there's three North Carolina craft malt houses that have opened and that's really bridged the gap between farm to brewery.

Partnering with the malt house like Epiphany Craft Malt, they've given us access to not only the brewing industry, but also education about what's important for malting grains.

Here, we can look and we can touch and feel and participate in the process in a great way, which really exciting for us in this emerging North Carolina craft beer economy that we're growing together.

- [Narrator] Some of Kuhls barley ends up at Bull City Burger and Brewery in Durham.

At six in the morning, brewers pull 50 pound sacks of malted barley to begin the process.

- My name's Luke Studer.

I am the Head Brewer at Bull City Burger and Brewery, and I'm in charge of beer production.

We start the brew day with milling the grain.

We're cracking open that barley kernel to expose starches.

It runs through our auger system and drops into the mashton.

The mashton is where we mix the cracked grain and hot water.

- [Narrator] Enzymes break down starches in the grain to convert sugars into alcohol.

Later, barley husks settle on the floor of the stainless steel tank.

That's what brewers call spent grain.

Meaning, the grains have no further use to the brewery, but the spent grain does have a market.

- [Luke] Farmers are always looking for spent grain.

Breweries are always looking for an easy way to get rid of spent grain.

Find a local farmer, and yeah, make a partnership with them.

It works out great for both parties involved.

- [Narrator] That's where Watt Parker, farmer and president of the Durham Cattleman's Association, comes in.

He's driven 26 miles from his farm in Northern Orange County to get spent grain for his cows.

Parker's been picking up the grain for the last four years.

[car engine revving] Parker feeds his cows mornings and afternoons.

He mixes one bucket of pelleted commercial feed with two buckets of spent grain.

[cows mooing] - From week to week, we'll run out and when we feed 'em just the dry pellets, they kinda turn their nose up at it.

They're like, "Hmm, I miss my beer, miss my spent grain," you know?

So they really like it, and the wet factor of it is a lot better than just a dusty pellet.

So they really like the spent grain.

They really do.

- [Narrator] 20 miles away in Western Orange County, Steel String Brewery is making beer for its taproom and Carrboro and retailers in the Triangle.

The brewery at Pluck Farm treats all water it uses with a state-of-the-art septic system.

Head of Brewing, Will Isley, was one of the founders of Steel String in 2013.

- So we do have a lot of effluent or water discharge that comes out of our systems, and that all goes into our onsite treatment facility because we are a bonafide farm.

We have a five step process with our water treatment, where it goes through a grease trap.

It's basically a holding tank for the pH and the temperature to come down.

- [Narrator] Gray water flows into an underground system that irrigates the brewery's garden, orchard and picnic area.

- It is about creating a sustainable agricultural model, where we know that our money stays in this state and we know that we're supporting people who are doing things that are good for the states, both the economy and agricultural side of things.

We wanna make sure that what we're putting into the ground and what we are contributing to the waterway is as clean as possible.

- [Announcer] Thanks for watching.

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