Water Into Wine

Jim Lauria

As a young engineer on a farm in California's Central Valley grappling with the challenge of injecting fertilizer into irrigation water, Angelo Mazzei didn't consider how his career would ultimately turn his knowledge of water into a deep involvement in wine. But since he crafted first high-efficiency venturi injectors in the 1970s in his garage to help improve water, fate and business have pulled Angelo Mazzei toward wine from every direction.

Entering at Ground Level

Mazzei developed his first venturis to inject fertilizer into irrigation water, harnessing 200-year-old technology to solve a very modern problem. Building on a design developed in 1797 by Giovanni Venturi, Mazzei directed pressurized water into a conical chamber where it is compressed, then channeled through a narrow throat into another cone-shaped chamber that allows it to expand. As the compressed fluid expands in the wider space, its pressure drops dramatically, creating a vacuum. Mazzei used that vacuum—created solely through physics, with no moving parts—to draw fertilizer through a suction port into the injector, and quickly mix it into the fast-moving flow.

Today, Mazzei injectors are at the heart of fertigation systems on farms all over the world, including vineyards. Paired with today's high-tech control and sensor technology, the venturis are part of state-of-the-art precision agriculture systems, spoonfeeding grape vines and helping viticulturists feed and protect their crops.

The Power of Ozone

Almost as soon as Angelo and Mary Mazzei began producing venturi injectors in their Bakersfield garage in 1978, Mazzei Injector Company began its dizzying growth, building manufacturing and engineering capabilities that have tailored venturi injectors to a wide range of fluid/fluid and fluid/gas mixing challenges.

Among the most exciting in recent years has been the role of the venturi in injecting and mixing ozone to create powerful sanitizing systems in applications ranging from hot tubs to municipal drinking water. Over years of perfecting ozonation systems—guided by in-house computational fluid dynamics (CFD) modeling and other engineering strategies—Mazzei has developed considerable expertise in clean-in-place (CIP) technology.

Of course, sanitation is absolutely vital in the winemaking process. Many winemakers have adopted ozone as an effective, organic, residue-free alternative to harsh chemical sanitizers, and are drawn by the fact that ozone is highly soluble in cold water, minimizing the need for steam and heated-water sanitation. Building upon the expertise gained in developing injectors for ozone sanitation systems in industrial and municipal markets, Mazzei injectors play a pivotal role in ozone injection and mixing in winery CIP systems, including stationary and mobile units.

Taking the Horror Out of the Lagoon

Process water—including used CIP water—from wineries often finds its way to wastewater lagoons. That's another familiar environment for Angelo Mazzei. In fact, one of his early projects was developing an aeration system that used venturi injectors to enhance the environment for odor-controlling microbes in a vegetable processing plant's wastewater lagoon near his home. Venturis draw air into recirculating wastewater streams, which are then discharged through mass transfer nozzles at the bottom of the lagoon. The specially engineered nozzles shear the entrained air into tiny bubbles that float up through the wastewater, contacting a huge volume of fluid on the way to the surface and dissolving more oxygen into solution.

Unlike surface agitators, which require significant maintenance and high energy inputs to paddle air into the top few inches of the water, the bottom-mounted mass transfer nozzles take advantage of the fact that oxygen transfer occurs more effectively under pressure, which allows the weight of the lagoon's water to enhance the efficiency of the system.

Today, Mazzei Injector Company has aeration systems in countless lagoons treating wastewater from agricultural, municipal and industrial operations. Winery lagoons fit right in with the other wastewater facilities the company aerates.

A novel application for the company's venturi injectors is aerating winery wastewater (as well as industrial process water and even dairy manure on farms) before it is applied by sprinkler to beds of wood shavings in the unique BioFiltro BIDA water treatment system. Microbes and worms in the wood shavings remove contaminants from the water and convert them into useful fertilizer in a low-energy process. Aerating the water maintains a healthy environment for aerobic microbes.

Pump-Over Aeration

The same principle behind aerating wastewater—creating a healthy environment for beneficial microbes—applies to winemaking, which harnesses yeast cells' ability to turn sugar into alcohol, CO2, and other compounds.

Juice traveling through one of Mazzei's pump-over aeration venturis draws in air as it passes through the conical chambers, then encounters specially designed vanes that enhance the mixing process before the wine is directed back into the tank. The result is highly efficient aeration that innovators have been documenting with scientific instruments that test oxidation reduction potential, also called ORP or redox.

ORP is a key parameter in winemaking: when fermenting must is in an oxidative state, yeast is healthy and productive. But if oxygen levels drop and the must shifts to a reductive state, elemental sulfur in the juice can undergo chemical conversion to hydrogen sulfide, which can give wine a rotten-egg odor.

Generations of winemakers have used their noses to monitor hydrogen sulfide production, alerting themselves to the need for aeration. But today, electronic ORP sensors can detect far more subtle changes. Mazzei has been working to integrate venturi injectors with sensors and servo controllers in a self-regulating macro-aeration system that adjusts pump-over rates to maintain the optimum oxidative state. It's not the first time Mazzei's engineers have worked with this sort of system: electronic ORP monitoring has been used for years in the water treatment industry to ensure that aerobic treatment processes were being run as efficiently as possible. As with fertigation, root zone aeration and CIP, Mazzei brought insights and experience from other parts of its business to the wine industry.

Big Name

Though he has been a pioneer in the water treatment business, Angelo was hardly the first person named Mazzei to get into the wine industry. In fact, the Mazzei name has been associated with wine since 1398, when notary Ser Lapo Mazzei was the first person to document the Chianti appellation. His granddaughter married into the region's wine industry. Twenty-four generations later, the Mazzei family is still producing wine on her estate—including renowned Super Tuscans—as well as Maremma and Vermentino on another Tuscan estate and Nero d'Avola, Syrah and Petit Verdot in Sicily.

The Mazzei family of Italy has also touched America in a special way: Philip Mazzei was a friend of George Washington, Ben Franklin, John Adams and Thomas Jefferson (who invited Mazzei to plant winegrapes at his Virginia estate, Monticello). In fact, Mazzei's writings were said to inspire Jefferson to write "all men are created equal" into the Declaration of Independence.

Angelo Mazzei has visited the Mazzei wine family in Tuscany several times and stays in close touch, and there may be a chance that there's a blood tie as well as the bonds of friendship and name that connect them. And no matter what the genealogical research ends up saying, Angelo seems fated to connect with the wine industry.