EQUIPMENT

Smokers*

Though technology has streamlined the process, smoking still requires a human touch

By Sue Robinson

*Source: Copyright © 2000 Seafood Business - Posted with permission from Seafood Business

As a boy in northern Scotland 40 years ago, Alan Spence stoked the fires and tested the wind in the brick smokehouses for the local salmon processors. Sometimes he would wake in the night to discover the wind had shifted or the humidity had changed and knew the fires needed to be adjusted.

"We used to light fires on the floor, so sometimes those burst into flames, and sometimes they would go out, and any subtle change in the weather was very intense," Spence recalls. "Those old-fashioned smokehouses needed constant monitoring."

Today, the president of Spence & Co. in Brockton, Mass., sets dials and computers instead of fires. The brick smokehouses of his past have been replaced with computerized units that control humidity, temperature and even wind and weight.

Spence says, "The artistry in smoking is still there – only we have a lot more control over the environment. When I was a kid, we would have to worry about the wind direction; these kilns have wind-speed control, they have smoke control."

His hometown of Aberdeen witnessed the invention of the modern stainless-steel AFOS kiln, used in 98 percent of Scotland’s smokehouses and popular throughout the Americas and Europe. One of the largest manufacturers of smoking equipment, AFOS Ltd. has been making horizontal-flow machines for 50 years.

"But I would not say there is anything truly revolutionary about the equipment we use today," Spence says. "The bottom line is, you still have to know what you are doing."

Smoker manufacturers agree with Spence to a point.

"There is no doubt that every operation lends its own touch to its product, regardless of the technological advances being made in this field every day, and in those regards the process has not changed," says Mark Carlisle, owner of International Smoking Systems in Ashburnham, Mass., which sells AFOS kilns.

"But when you talk about the last 10 years," he adds, "there has been a lot of progress in the areas of controls, microprocessors, CPUs, that just did not exist before. Everything is getting to be so much more simplified."

The basics of smoking

Smoked foods have been produced by the same basic method ever since the process began. Air, smoke and wood have always been the main components in smokehouses. But instead of depending on Mother Nature, processors today use technology to create the air and smoke.

Most modern fish plants use a forced-air oven, or kiln, in which air and smoke are mechanically pumped in a horizontal flow around seafood on flat racks.

Vertical-flow ovens, designed to smoke hanging product, are more often used for smoking large fish. In these units, air blown in from the top of the machine flows down either side and then upward. A design advancement is the addition of dampers to create oscillating air flow, preventing the air voids that can otherwise occur in vertical-flow smokers.

Most processors consider these units more labor intensive and less efficient than horizontal smokers, and they find load capacity limited.

Steve Mackiewicz, president of Furnace Creek Gourmet Smoked Seafood, favors horizontal smokers. He notes, "In the horizontals, I can hang something, or I can do the flat-tray product. And I can get the coloration and the drying equal – there are no hot or cold spots."

The first step

Prior to smoking, fish is normally soaked or coated in brine. The brine usually is made up of salt as well as brown sugar, garlic or pepper to add flavor and to help dry the product out. European processors are experimenting with injecting brine into the fish to speed up the drying process – a method many U.S. plants frown upon because it makes the smoked fish less firm and silky – even though it cuts the drying and smoking process down anywhere from 10 to 24 hours.

After brining and drying, seafood is either hot- or cold-smoked. Modern kilns can do both. With hot smoking, the product is heated to a temperature of at least 145 degrees F. Cold-smoked seafood is processed at 70 to 80 degrees F.

As demand for seafood smokers has grown, oven manufacturers have enhanced certain characteristics of their ovens to increase smoking efficiency. The results are new and improved units that adhere to the traditional tenets of smoking but have simplified the process.

New technology

As with most seafood-processing equipment, computerized features have given processors much greater control over the smoking process.

"The basic principles have not changed over the last 100 years, but now it is all computerized," says Lee Rubin, vice president of marketing and sales at Acme Smoked Fish Corp. in Brooklyn, N.Y. His 90-year-old company still uses old-fashioned brick smokehouses, revamped to accept modern-day conveniences.

He notes, "Now we can control humidity, heat, the time the oven goes on and goes off, and the amount of smoke it makes – everything. It makes it almost idiot-proof."

One of the biggest concerns in the fish-smoking process had been shrinkage during the drying stage. Since fish has an 82 percent moisture content, much of the product could be lost to steam in smoking. But scales have now been incorporated into the ovens, allowing processors to program the smoker to shut off when product reaches a desired weight.

Temperature is also constantly checked, says Patrick Martini, director of sales and marketing for Oregon-based Enviro-Pak, which produces equipment that monitors the products’ core temperature from input to output. Automatic heat and damper controls ensure uniform temperature and humidity; most machines on the market offer a range of 65 to 225 degrees F.

"For a programmed amount of time, air flow will go in one direction, from one side to the other, and you keep on changing the flow by directing it with alternating dampers," explains Michael Dernburg, president of the 60-year-old smoker company MPBS. "This way, you create a uniform air flow in the house by eliminating back-flow pockets that can cause uneven drying."

"Flow-through" smokers that allow fish to make one trip straight through have also hit the market in recent years.

"There are doors at both ends, so you can keep your package inside, and there is no cross-contamination," Martini says.

And while fish smokers of old relied on wind to help dry the fish and direct the smoke, today’s processors can create airflow and heat with a keyboard.

"You can sit in your living room and control the kiln by a modem, and make changes in the process," notes Carlisle.

One of the latest improvements has been a dehumidifying attachment. Many smokers use the air circulating in the refrigerated storeroom or plant to dry out the product in an open-system machine. On humid days, it takes longer to smoke seafood.

Now, dehumidifiers – refrigerated-coil systems or fans – treat the air before it blows over the fish, adding one more control opportunity for smokers. It’s energy-consuming, say some processors, but worth it.

Carlisle explains, "The dehumidification system through refrigeration takes the moisture out of the kiln itself. It will smoke the same, and it doesn’t matter if you have a refrigerated plant or not."

One welcome new feature is a self-cleaning apparatus for the smokehouse itself and a separate washing machine for the tray trolleys. Depending on how much volume is involved (a separate stainless-steel trolley cleaner can run more than $50,000), these can cut down on both time and money.

"You roll a trolley into [the cleaner], and it basically spray-washes the trolley as it turns around. You can add whatever chlorine or disinfectants you want to the water" says Des FitzGerald of Ducktrap River Fish Farm, who installed the new equipment in his Maine plant in April. With it, one employee can accomplish what once took three workers to do. "This is going to save us a good deal on labor," Fitzgerald notes.

Despite all the cost- and time-saving enhancements to modern smoke ovens, those in the business maintain that the process will never become fully automated. Each fish and every smoke is different, they say, and smoking needs a knowledgeable, human guide to determine such factors as type of wood or variety of brine to use in the process.

Don Horton, president of Horton’s Downeast Foods concludes, "You can take all the fancy machines you want, but we prefer to adhere to the old-fashioned methods. Time consuming, yes, but I can not conceive that there is a better way when you come right down to it."