Brazilian researchers use ultrasound to make processed food healthier

. Sep 20, 2018
processed food fruits ultrasound Healthier processed fruits thanks to ultrasound

When thinking about ultrasound, one usually associates it with a technology used to monitor health or pregnancies, not with the kitchen. Now, however, this tool can be used to make food healthier, according to a research group from the University of São Paulo. Ultrasound technology can enhance the nutritional properties of fruit juice, for instance, creating better quality coconut water by deactivating proteins which cause undesirable changes to the color and transparency of the liquid when industrialized.

The Process Engineering Studies Group (Ge²P), from the Luiz de Queiroz College of Agriculture of the University of São Paulo (Esalq/USP), has been researching the use of ultrasound in food processing since 2013.

By studying how ultrasound works, how it propagates in food materials and properties, the scientists realized that this technology could be useful in the production of fruit juices. &#8220;We began by studying the changes in the structure of the material, then we moved to the physical aspects (for example the decantation of pulp, texture) and then nutritional,&#8221; says Pedro E. D. Augusto, Associate Professor of Food Process Engineering. </span></p> <p><span style="font-weight: 400;">Brazil is the third largest <a href="">producer</a> of fruit in the world, but only 40 percent of Brazilians eat fruit every day, </span><a href=""><span style="font-weight: 400;">data shows</span></a><span style="font-weight: 400;">. According to the Brazilian Fruit Institute (IBRAF), per capita consumption in Brazil is 57 kilos per year, The European average is 129 kilos of fruit and vegetables per year, according to FreshFel, the European association of fresh produce. The World Health Organization recommends the consumption of at least 146 kilos per year. Fruits and their products, such as juices, are an integral part of a healthy diet, Mr. Augusto says. Food processing can ensure the availability of these products in a safe, convenient and quality way. &#8220;This is our goal,&#8221; he explains.</span></p> <hr /> <p><img class="alignnone size-large wp-image-8888" src="" alt="processed food fruit consumption" width="1024" height="683" srcset=" 1024w, 300w, 768w, 610w, 1200w" sizes="(max-width: 1024px) 100vw, 1024px" /></p> <hr /> <p><span style="font-weight: 400;">So far, the project has managed to improve the consistency and stability of fruit pulp, as well as the structural modification of the juice, which results in the improvement of its properties. The process avoided the precipitation of the juice pulp and ensured a more pleasant texture. &#8220;At a time of great discussion about processed products, we were able to use a physical technique to improve the quality of a fruit juice, without the need to use other ingredients,&#8221; said Duarte Augusto.</span></p> <p><span style="font-weight: 400;">Even though there is a difference between working with human bodies and fruit, the ultrasound technique used is basically the same. The main difference is the amount of energy involved. In devices used in medical analysis, a small amount of energy is used, because the objective is to capture the waves reflected by the material, without altering it, explains Mr. Augusto. &#8220;Our case is almost the opposite: we want the waves to transmit a great amount of energy, to the point of being able to modify the material,&#8221; the researcher says.</span></p> <hr /> <p><span style="font-weight: 400;"><img class="alignnone size-large wp-image-8889" src="" alt="processed food fruit consumption" width="1024" height="536" srcset=" 1024w, 300w, 768w, 610w, 1200w" sizes="(max-width: 1024px) 100vw, 1024px" /><br /> </span></p> <hr /> <p><span style="font-weight: 400;">The technique can be used on various other foods and for many purposes. For example, the researchers have also used ultrasound to accelerate processes such as grain hydration, vegetable acidification, and fruit drying, obtaining higher quality dried products, improving the properties of starches and even incorporating nutrients into foods, among other applications.</span></p> <p><span style="font-weight: 400;">Now the focus of the research team is studying how technology modifies the structure of the product and how we can use those changes in our favor, for example by improving its nutritional qualities.

Diogo Rodriguez

Rodriguez is a social scientist and journalist based in São Paulo.

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