Polyphenols as markers of authenticity of bakery products containing chia, flax and sesame seeds.

AGUSTÍN LUCINI MAS; FEDERICO BRIGANTE; NATALIA PIGNI; DANIEL WUNDERLIN; VERÓNICA BARONI

Nantes

Conferencia; 5th FoodIntegrity Conference; 2018

FoodIntegrity

Nowadays, new trends in food are incorporating specific ingredients to improve the quality of the product or the health of those who consume it. Because of this, people have special interest in what they eat and in the ingredients that constitute it. From this, it turns necessary to develop tools and methods to corroborate that the foodstuff complies with what is informed on the label and thus, determine the authenticity of the food and its ingredients. Chia, flax and sesame seeds are now widely used as ingredients of foodstuffs because of their beneficial effects on health. These seeds are an important source of unsaturated fatty acids, which have a positive effect on the circulatory system; and antioxidant compounds that prevent cell aging and the risk of having some diseases such as diabetes, cancer, Parkinson's and Alzheimer's. The compounds responsible of this last effect are polyphenols, organic compounds present in plants. This makes polyphenols candidates to determine the presence of certain ingredients of plant origin. However, it is necessary to consider that in the process of making a food product, the polyphenolic compounds of the ingredients could be modified; therefore, only the compounds that resist this processing could be used as markers. The aim of this work was to generate a method to determine the presence of chia, flax and sesame seeds in bakery products using polyphenols as markers. For this, extracts of the seeds were obtained by sonication with solvent methanol:water (50:50) of the previously defatted seeds. Then, the markers found in seeds were searched in cookies made at our research facility to determine which compounds resisted the processing. After that, to evaluate the usefulness of the methodology, markers found in our cookies were searched in different commercial bakery products containing the seeds (sweet cookies, crackers, bread, puff pastry dough and breadsticks). In addition, in both the flax seeds and all the commercial and samples that contain it, a basic hydrolysis step was also performed to release the compounds of this specific matrix. All these extracts were analyzed by HPLC-DAD-ESI-qTOF using MSn spectra, UV-Vis spectra and exact mass comparison to determine the polyphenolic profile.In chia seeds, 30 compounds were found belonging to the families of organic acids, flavonols, amino acids, and hydroxycinnamic acids; being the last ones the most characteristic and the majority. On the other hand, in sesame seeds, an amino acid, a hydroxycinnamic acid, a flavone and 28 lignans were found, being these the most characteristic. In addition, in flax seed, 28 compounds were found among lignans, flavonoids, hydroxycinnamic acids and amino acids.Although there were ubiquitous components in all the seeds, some of them allowed to differentiate between these seeds. In all the samples containing chia seed, 3 hydroxycinnamic acids (Salviflaside, Rosamrinic acid and Salvianolic acid) were found; in those with sesame, 3 lignans (Sesaminol trihexoside and two isomers of Sesaminol dihexoside), while the only compound that allowed to differentiate flax was the flavanone Eriodictyol-7-0-hexoside. Even though other polyphenolic compounds were found in commercial samples such as Tryptophan, Quinic acid, Ferulic acid, Quercetin dihexoside, among others, these were not useful to differentiate between the different seeds because they are present in more than one of them.In conclusion, there are certain polyphenols that can be used as markers for the seeds of chia, flax and sesame in food because they are characteristic of each of them and they resist processing.