Opinion: fruit as a source of functional food
By Valerie Weinborn, University of California Davis PhD student in Food Science
Nutritional support is without a doubt a fundamental aspect of food, but thanks to advances in technology and new discoveries we can also focus on another point – how to use food to improve the health of well people? It is here that the concept of functional food becomes important.
Functional foods are foods that – in addition to nourishing – contain a bioactive ingredient, or in other words present some kind of function or activity in addition to their nutritional properties. In this category we can find foods that, for example, naturally or artificially contain antioxidants, probiotics or prebiotics.
Antioxidants are molecules that protect and repair the deterioration produced in our cells by free radicals, which are unstable and highly reactive compounds capable of generating oxidative damage related to cancer and aging. By incorporating fruits with significant amounts of natural antioxidants in our diet, we can significantly reduce the harmful effects caused by the presence of free radicals.
Beta-carotene, Vitamin C and Vitamin E are the three main natural antioxidants, and we can find them in colorful fruits like grapes, apples, apricots, melons, mangoes, peaches, strawberries and berries in general, walnuts and seeds.
Probiotics are live organisms (bacteria), which when administered in adequate quantities have beneficial effects on health, such as stimulating the immune system and maintaining the equilibrium of intestinal flora. Traditionally, probiotics are found in dairy products like yogurt, but in recent years there has been the development of plant-based products that have them, such as fruit juices that have these organisms added.
Prebiotics are compounds, mostly fibers, that our organisms are not capable of leading, and when they arrive intact in our large intestine they become a food source for our colonizing bacteria. The particularity about compounds with prebiotic activity is that they can only be utilized by specific bacteria groups that have a positive effect on the host’s health, or in other words us, when metabolized.
Among the fruits rich in prebiotics are tomatoes, berries (blueberries, raspberries, blackberries) and bananas.
A lot of efforts and research have been undertaken in the last decade focused on the search for new sources of prebiotic compounds, specifically those like oligosaccharides (medium length complex sugars) that are found in human milk. Many infants don’t have access to human milk , and while baby formulas today have prebiotics, they don’t present the same benefits found in natural milk.
This is why finding alternative sources is so important. In this regard, investigations have opened to the search in plant-based products such as fruits – grapes for example – in which a presence of these active compounds has been described.
In addition to a possible use in developing new food products, just the fact that fruits have one or more types of functional compounds – properly described, tested and analyzed in their active power – delivers added value to the fruit without changes, which is of special interest to growers and retailers, who could look to trading in new niches and accessing all the benefits that entails.