Just Remove Water: New ways to achieve an old objective drive success of dried produce

They’ve come a long way, baby.

Drying foods like grapes, apricots, dates, figs and plums in the air and sun is one of the oldest ways of preserving food – and especially significant before refrigeration, freezing, canning and processing provided safe alternatives.

In more recent times, drying fruit became a way to make commodities available year round.

“The reason for drying the fruit in the first place is, if you don’t dry it, you don’t have a way to enjoy it through the whole year – only around harvest,” said Alan DeVore, president and CEO of Michigan-based Graceland Fruit.

With about $70 million in annual sales, the company produced between 27 and 30 million pounds of dried cherries, cranberries, blueberries and apples last fiscal year. Doing business in 50 countries – the largest market being South Korea – Graceland has launched its own line of branded retail consumer products in addition to producing for traditional niches like foodservice and processors.

“You’d be eating cherries, for example, just in the summer months and early fall, and cranberries at Thanksgiving and Christmas,” DeVore said. “That’s pretty much it. This way, when we dry it, you have the ability to set them on the shelf and pull them out any time at your convenience.”

Drying also maximizes yield, said Brent Charleton, senior vice president of corporate affairs for EnWave. The British Columbia-based company has developed an alternative technology for drying fruits and vegetables, among other products.

“The preservation of food to minimize waste is very, very important going forward, as the population continues to spike in many jurisdictions,” Charleton said.

And then there’s the explosion in health-conscious eating in the United States and abroad. That’s opened even more doors for the dried produce segment, with consumers increasingly turning to dried fruit and veggies as substitutes for candy, chips and the like.

“People are looking for healthier ways to snack,” DeVore said.

Continuous Drying

These days, the process of drying fruits and vegetables is a lot more complicated than leaving them on a rock in the sun. Processors are employing a variety of techniques to achieve the same end: a product that looks good, tastes good and will retain shelf life.

“When you think of dried fruit, you think prior to the ‘80s, it would have just been raisins, dates, figs – fruits that are very high in natural sugar,” DeVore said. “So if you took something like a cherry or cranberry or blueberry, there’s not nearly enough natural sugar in the fruit to make an acceptable dried product.

“So what happens (now) is in order to dry it, you need to infuse it with sugar. That’s really where the science comes in – how to infuse it properly to get the right amount of sugar into it so you can properly dry it.”

And producing a product that is consistent is key.

“We got started on what’s called the professional ingredient market – that’s probably the most demanding one because you sell to large companies or other people that take your product and put it into something they’re making,” DeVore said. “So they demand a lot of us as an ingredient maker … they don’t want surprises. If there’s a variant or change in what we’re offering them, they’ll spot it right away.

“Anybody can infuse it and anybody can throw it in a dryer,” DeVore said. “The question is: what are you going to get out of it on the other end?”

Graceland uses a continuous dryer technique. Fruit goes onto a belt and moves through a dryer.

“You treat a cherry or blueberry or apple differently,” DeVore said. “And cranberries are completely unique. Our systems were modified to handle the different times of fruit processing – it evolved over time as we got a better understanding.”

Like many processors, Graceland freezes fruit before infusing it with sugar.

“When fruit freezes, the water inside expands just before freezing so it helps break down the cell walls so the infusion process is greatly aided,” DeVore said.

The only other ingredient in Graceland’s dried fruits is sunflower oil.

“Sunflower oil is more or less a processing aid,” DeVore said. “It helps us get (the fruit) off the end of the dryer when it comes out. We use a very light amount.”

Freeze Drying

Located in Fairfield, New Jersey, Crispy Green enlists freeze drying to produce its line of Crispy Fruit Snacks that include apples, Asian pears, bananas, pineapples, mangos, cantaloupe and tangerines. Fruit sourced from selected growers is peeled, cleaned, chilled and frozen. Then the slices go into a vacuum chamber where moisture is removed by evaporating the ice in temperatures that can dip to minus 50˚ F.

“The process removes 99 percent of the water and leaves behind the true essence of the fruit,” said Crispy Green National Sales Director Mark McHale. “The end result: light, flavorful slices of fruit that retain nearly all of the nutrients of fresh fruit (and) a unique, crispy texture with no additives.

“The biggest challenge of this process is the moisture control within the production line. Humidity can easily ruin the finished products.”

With double-digit growth, McHale said the freeze-dried fruit segment is the fastest-growing in the dried fruit category.

“We have modified the freeze-drying process over the years to improve the taste and texture of our products,” he said. “What makes this category unique is the fact that freeze-dried fruit is truly a naturally healthy product that crunches like a snack of a less-healthy profile.”

High-Speed, Low-Temp

EnWave’s nutraREV technology uses a combination of vacuum pressure and microwave energy to deliver a high-speed, low-temperature food dehydration process that results in cost savings over other methods. The company doesn’t dry products itself, but licenses or holds agreements allowing its patented technology to be used by a variety of processors.

“We currently have a number of companies using our technology to dehydrate fruits and vegetables,” Charleton said.

EnWave’s system differs from freeze or air drying in that it can take a precise amount of moisture out of a product load at very low temperatures, Charleton said. That means less processing time.

He describes a California spice company that uses the EnWave system to dry bay leaves.

“They’re using our technology to dehydrate these product loads in about 14 minutes, as opposed to if they were trying to freeze dry, it would take multiple hours,” Charleton said. “Using our technology, it retains a high amount of volatile oils, it’s more pungent, the leaf itself is supple, the color is still vibrant – it’s green – and they sell it as a spice.”

EnWave has also worked with a company that uses its technology to produce a wide range of dehydrated fruit and vegetable products including powders. Others are dehydrating berries and tropical fruit products. Still another is using the system to dry a high-end herb typically consumed with sushi.

“The water’s being removed,” Charleton said, “but it’s not as fragile in terms of structure.”

Kathy Gibbons, contributing writer

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