Evaluation of acrylamide in foods and development of some strategies for its reduction
- Autores: Mariola Sansano Tomás
- Directores de la Tesis: Ana Belén Heredia Gutiérrez (dir. tes.), Ana María Andrés Grau (dir. tes.)
- Lectura: En la Universitat Politècnica de València ( España ) en 2017
- Idioma: español
- Tribunal Calificador de la Tesis: José Ángel Pérez Alvarez (presid.), Daniel Vidal Brotóns (secret.), Matteo Mario Scampicchio (voc.)
- Materias:
- Enlaces
- Tesis en acceso abierto en: RiuNet
- Resumen
Although the presence of acrylamide in foods was detected a decade ago, public concern about this issue, and in general about food health, seems to have increased in recent years. Acrylamide is a toxic human carcinogen present mainly in foods from plant origin and subjected to transformation processes in which temperatures above 120 °C are reached, such as frying and baking. Foods that mostly contribute to the intake of acrylamide are: French fries and chips, coffee and coffee substitute, biscuits, bread, pastries, battered and breaded products, breakfast cereals ..., being children and adolescents the most exposed population. From a chemical point of view, acrylamide is formed mainly from the reaction, during thermal processing, between asparagine and reducing sugars, as an intermediate product of the Maillard reaction.
In the last decade, both health authorities and the scientific community have made great efforts in scientifically establishing limits of toxicity as well as exploring strategies aimed at reducing acrylamide formation. The purpose of this doctoral thesis is framed in this last sense. On the one hand, our work has been focused on searching new strategies for acrylamide mitigation, in two different types of food: fried potatoes and battered products. The effect of an emerging frying technique, named hot air frying, as well as pre-frying treatments, were studied in fried potatoes. In the case of batters however, the strategy consisted in modifying their composition by adding a hydrocolloid, chitosan, after having tested its potential in model systems. Furthermore, the effect of chitosan addition on the physical properties of the batter formulations and on the quality of the final product was evaluated.
Finally, acrylamide bioaccessibility of the food products with the highest acrylamide content was addressed. These food products were subjected to an in vitro gastrointestinal simulation in order to study how acrylamide content progressed throughout the digestion process.
Results showed that air fried potatoes as well as chitosan addition to batter formulations reduced the formation of acrylamide by about 90 and 60 %, respectively. The modification of the characteristics of chitosan (molecular weight and deacetylation degree) conditioned its ability to reduce the formation of acrylamide. Furthermore, the incorporation of chitosan to batters reduced the absorption of fat during frying. Chitosan increased viscosity and consistency of batters but, the color and texture of the fried products were not significantly altered.
The total replacement of wheat flour by rice flour allowed to obtain gluten-free batters with similar viscosity, when adding chitosan. This new formulation could be adjusted to gluten-free battered products.
The simulation of in vitro digestion showed a significant increment of acrylamide after the gastric stage in a wide range of foods. However, acrylamide bioaccessibility (after the intestinal stage) was reduced until pre-digestion levels or even lower in chips and French fries.
