New Juice Process Takes The Pulp Out Of Fruit Juices

May 6, 1998

GAINESVILLE—Citrus and berry growers can squeeze more value out of their crops using a new juice processing technique invented by a University of Florida researcher.

Consumers, too, will benefit from the process, which allows juice-makers to use natural sweeteners, rather than corn syrup, said Chin Shu Chen, a food engineering professor with UF’s Institute of Food and Agricultural Sciences.

Chen’s process clarifies fruit juice, producing a clear juice with no pulp. Under the process, even orange juice can have the consistency of apple juice. UF has patented the process in the United States and has applied for an international patent.

Under Chen’s process, pulpy fruit juice concentrates and purees can be reprocessed during the off-season in citrus processing plants using existing evaporator and membrane equipment. This allows for year-round use of the equipment and eliminates juice-makers’ dependency on seasonal fruit supplies.

Because concentrates and purees can be stored several months, purees of fruits not widely available in Florida — such as banana puree from Central America — can be shipped here and then processed and blended with juices of Florida-grown fruits.

The potential of using clarified juice for new product development is immense, Chen says.

In the citrus industry alone, for example, clarification can turn frozen concentrated orange juice, the most enduring form of orange juice, into more convenient ready-to-pour forms.

Frozen concentrated orange juice was developed by researchers at the Florida Department of Citrus and patented in 1948. It still accounts for about a third of the $3-billion orange juice business in the United States.

Orange juice concentrate that is clarified, however, does not have to be frozen and mixes more readily with water than traditional concentrate. It also has a longer shelf life than orange juice concentrate.

“It’s an issue of convenience,” Chen said. “This juice can also be placed in the chilled juice section of the supermarket instead of the frozen food section.”

The process also makes other new juice products possible. For example, banana puree is a favored ingredient in blended fruit juices but has limitations because of its thickness. Taking out the pulp would improve its appearance and allow wider use, Chen says.

“Bananas have very little acid, so they make things sweeter,” Chen says. “They also add potassium to the diet. This is good for active children and adults who lose potassium through exercise.”

Banana juice imparts a sweet, neutral taste that would allow processors to sweeten fruit juices without altering flavors.

“You can add clear banana juice to orange or grapefruit juice and it still tastes like orange or grapefruit juice,” Chen said.

Even though orange juice is rich in vitamin C, pediatricians usually do not recommend it for babies because of its high citrus acid content and pulp. But banana-sweetened clear orange juice would be more suitable for baby juice, Chen says, since the acid would be reduced, and no pulp would remain to plug bottle nipples or sippy cup spouts.

Health-conscious consumers also benefit. Currently, most juice drinks contain corn syrup and little fruit juice, Chen said. Under his process, clarified banana juice can be substituted to make healthier, 100-percent natural fruit juices.

Chen says smaller fruit crops will reap dividends as well.

“Strawberry and blueberry growers will now be able to process what they can’t sell in the fresh market. Strawberries are more than a $100-million industry, with the excess crop processed into strawberry puree. But the market is saturated for this,” Chen said. “Some fruit are abandoned because they are worth less than the cost to pick at the end of the season. If we process this puree into juice, however, we can supply the juice concentrate to the multibillion-dollar beverage industry.”

Florida blueberry and strawberry crops currently have no processing facility of their own, he said, because they can’t afford it.

“But we can utilize citrus processing plants to process blueberries and strawberries for value-added products to benefit both industries. Everyone can make money,” Chen said. “And the consumer will benefit.”