Nutrition Argentina Bahía Blanca, Buenos Aires, Tuesday, April 28 of 2015, 09:20

Researchers study the processes to preserve and enhance the quality of food

Science and technology are key factors to optimize productivity, food preservation methods and nutritional, health-hygiene and sensory quality of the products

CONICET/DICYT Traditionally, Argentina has played a significant role in food production for local consumption and exportation. Science and technology are key factors to optimize productivity, food preservation methods and nutritional, health-hygiene and sensory quality of the products.


Amalia Carelli, Conicet independent researcher at the Planta Piloto de Ingeniería Química (Plapiqui, Conicet-UNS) and coordinator of the Food Engineering Area of that institute, comments: “we focus on the development of products and processes applying clean technologies, the use of enzymes, by-products recovery through secondary currents and oils processing”.


About this line of research, the chemical engineer explains that they work on the description and quality control of vegetable oil, mainly from sunflowers and olive in Argentina. Carelli highlights that many of the developed analytical techniques emerged from queries of the oilseed industry.


“It is necessary to know the chemical composition of the oil. In the case of olive oil, its adulteration is a problem. There are international regulations that set the limits of the composition to control its genuineness. As the national production has remarkably increased, adding new production areas, it is necessary to know the natural composition of the products the country exports. Another example is the sunflower oil because the dewaxing process, a procedure by which wax crystals are separated from oil, has to be controlled when it is for export”, the scientist explains.


Erica Baümler, Conicet assistant researcher at the Plapiqui, comments that the team studies the recovery of by-products obtained in the processing of oilseeds. Biophenols, a group of biomolecules that have antioxidant properties and modulate atherogenesis, are recovered from the production of the olive oil. Furthermore, they study the recovery of waxes from filter cakes from sunflower oil, and can be used for the production of edible films to cover food.


In spite of the advances in production and quality control of the vegetable oil processing, one of the main difficulties is its extraction. Ethel Pérez, Plapiqui assistant researcher, comments that the team is conducting some trials with non traditional Solvenst to improve this process.


“Hexane is used at a commercial level. It has good yields, but it has environmental and security problems for the workers because it is obtained from petroleum and it is explosive. One way to release oils is using a pre-treatment with enzymes in a water-extraction procedure, or by using other more environmentally friendly solvents. We are trying to optimize this alternative”, the researcher comments.


Regarding this, María Elena Carrín, associate researcher, explains that the enzymes can also be used to change the structure of the oil. The aim is to obtain semi-fat products similar to animal fat products but without cholesterol. Furthermore, since they are not obtained using the traditional hydrogenation process, they avoid the production of unhealthy trans compounds.


“We start with refined natural oils that have the insaturations beneficial to health. Through the use of enzymes, we change the position of the chemical chains. It is the same initial global composition but with some changes or aggregates of compounds that provide the semisolid feature that can be used in any food preparation the needs fat”, she explains.


Carrín explains that they work with lipases, complex proteins that act on fat and oils that are found in a great variety of living organisms. During the process, these enzymes are immobilized in a stand or they are used in a suspension. Afterwards, they can be removed with a filter and used again.


Developments for the fruit and vegetable industry


The Food Engineering Area does conducts research on vegetable oil as well as on fruit and vegetable processing. “The relationship with the companies from alto valle de Río Negro and Mendoza started many years ago with works with apples and pears. At the beginning, we provided quality control and then incorporated new processes such as the use of ultrafiltration, enhancing the pressing, the evaporation and concentration, and others”, Jorge Lozano, Conicet principal researcher at the Plapiqui, describes.


Likewise, the scientists of the Plant developed an extraction line and description of functional ingredients that are beneficial to health and reduce the risk of disease. The team determines its chemical properties and studies its inclusion in food.


“We have worked on the extraction of inulin from a tuber called topinambur and its use in bakery. The inulin is a dietary fiber that promotes digestion and has other beneficial parallel effects such as the cardiovascular disease control and it might prevent other types of cancer. Furthermore, we analyse it as a replacement for starch in dairy desserts to make them healthier. The team studies the extraction, implementation in food and its physical and sensory properties because it is important to know if the consumer would accept the product with these changes”, Diego Genovess, associate researcher at the Plapiqui.


Finally, Lozano comments that the food industry is peculiar because of its investment in scientific development and in product modifications. “In general, it works spasmodically, when it has a problem such as pollution or commercial rejection. Nevertheless, food consumers change their diet slowly, contrary to other choices, such as the technological ones. In the case of cellphones, people change them several times a year. Apart from all nutritional securities required, it is necessary to have all basic knowledge that problable will not be applied immediately or directly to the industry”, the scientist concludes.