A team of Spanish researchers believe they have created a new way for the food industry to utilise fresh fruits and vegetables as functional ingredients, in addition to battling ever declining intakes of fruit in the general population.
The team, led by Nuria Martínez Navarrete from the Universitat Politècnica de València, Spain, have so far produced powdered versions of grapefruit, kiwi and strawberries. They said that using freeze-drying techniques works to conserve the bioactive compounds that are responsible for the beneficial effects that fruits have on health and also maintains antioxidant levels.
"Grapefruit is a citrus fruit with great nutritional and functional value but its consumption is very small because, among other reasons, it is very bitter. Meanwhile, strawberries are a seasonal fruit. In powder, however, would open more markets" says Nuria Martínez.
"We chose kiwis because of its high vitamin C content, an especially labile component that has enabled us to strengthen the result for the study of the impact of the technologies applied in the functional value of fruit".
According to Navarrete, the powdered fruits can be used as ‘ready to sprinkle’ on other foods or could be utilised as a functional ingredient by industry.
Increasing intake
The Spanish research team explained that while fruit and vegetables are an essential part of the diet – with experts recommending at least five servings per day – consumption levels have been in gradual decline for some time.
One of the main drivers of this decline in consumption, they believe, is the lack of shelf life for the fresh products. Navarrete suggested that current fruit intakes are so low because fresh fruit only lasts a few days “and this clashes with our current lifestyle that in many occasions prevents us from shopping daily.”
“Because of this we consume more processed products that are long-lasting and easy to prepare.”
As a result, the team began to study the best way to achieve more durable products whilst safeguarding the key properties and nutritional value of the fruit. To achieve this, the team used a number of techniques, including lyophilisation (freeze-drying) and spray drying, to produce powdered fruit for use in foods.
Navarrete suggested that the tendency towards declining fruit intakes could change if the ideas stemming from the project are taken up by the food industry.