Harness vacuum infusion to improve texture of processed fruits, vegetables.

A goal of research across Europe is to demonstrate the industrial viability of vacuum infusion in processing fruits, vegetables, berries, mushrooms and similar products.

Vacuum infusion involves the removal of air from within vegetables by placing the product in a vacuum environment for 1 minute to 2 minutes at 0 bar to 2 bar. This treatment is followed by infusing or impregnating the product in a solution containing hydrocolloids, calcium or other solutes.

This infusion step improves their texture, appearance and other quality parameters. Investigators tested the technology on a number of vegetables, including whole or sliced apples, peaches, strawberries, pears, mushrooms, cucumbers and pumpkins. The infusion substances that they used were pectin, alginate, gelatine, gums, ascorbic acid, citric and malic acids, as well as calcium and some sugars.

Researchers used a newly developed mobile pilot plant for undertaking experiments in several countries in which research collaborations were underway: France, Sweden, Finland and Portugal. In particular, the vacuum infusion technology has shown excellent results and was able to improve the quality of thawed or pasteurized berries and fruits used for yogurt, marmalade and bakery fillings. The technique improved firmness and reduced drip loss.

The technology can be used as a pre-treatment before freezing or pasteurizing a product to improve sensory characteristics. Because of the novel products produced by this technology, the legal status of some products may have to be clarified, scientist indicate. If vacuum infusion is considered a new technology, legal authorization may have to be obtained by processors if it is used commercially on products.

Further information. Virginie Mahdi, Technologie Marketing Innovation, TMI International, Le Britannia, 20 Bd. Eugene Deruelle, FR-69432 Lyon cedex 03, France; phone: [phone]; fax: [phone]; email: [e-mail].