CHEMICAL PROFILE OF PHENOLIC COMPOUNDS IN WHEAT PASTA SUPPLEMENTED WITH CHIA

PIGNI, N; ARANIBAR, C; LUCINI MAS, A; BRIGANTE, F.; RIBOTTA P; BORNEO, R; BARONI M.V.; WUNDERLIN D.A.

Parma

Congreso; FOODINTEGRITY 2017 CONFERENCE; 2017

Chia seeds (Salvia hispanicaL.) are considered as a good alternative to produce supplemented foods in orderto improve its nutritional value. In our previous work, presented at FoodIntegrity 2016, we showed the analysis of quality parameters and antioxidantactivity of pasta produced with partial substitution of wheat flour withdifferent proportions of chia defatted flour (0%, 2.5%, 5% and 10%). We have demonstratedthat the increasing content of chia flour improves the antioxidant propertiesof the produced pasta.Generally, the antioxidant activity is associated with the content ofphenolic compounds. Considering that pasta is consumed after cooking and thatthe chemical profile of these components can be affected by high temperatures, ournext goals were to assess the antioxidant capacity of raw and boiled pasta and toanalyze the chemical profile of phenolic compounds through HPLC-MS. Initially,we performed the HPLC-MS/MS identification of the components of the acetone:water(80:20) extract obtained from chia defatted flour, determining the presence of 14phenolic compounds, among which 12 of them can be considered structurallyrelated to hydroxycinnamic acids such as caffeic acid, one was identified asquinic acid, and one corresponds to a flavone structure named hispidulin withvery low abundance (<1μg/g). The extract is characterized by the prominentabundance of two main compounds identified as rosmarinic acid and its glycoside.Both components together with other 9 compounds, all of them related to caffeicacid, have been reported in other Salviaspecies, but none of them had been previously reported in chia apart fromrosmarinic acid.Subsequently, we evaluated the extracts of raw and boiled pasta usingHPLC-MS quantitative analysis of the phenolic compounds detected in chia. Allthe polyphenols quantified in the extracts showed an increasing concentration correlatedwith the increased content of chia in raw and boiled pasta. On the other hand, theboiling process affected quantitatively the phenolic compounds profile. Caffeicacid, caffeic acid hexoside and danshensu showed higher concentration in boiledpasta than in raw pasta. However, rosmarinic acid glycoside, one of the mostabundant components in raw pasta, was not detected after boiling. This drasticchange indicates that chemical modifications are occurring which could explainthe elevated content of the 3 other molecules mentioned. On the other hand, thelevels of rosmarinic acid are not significantly affected by the boilingprocess, contributing to preserve the antioxidant capacity of pastasupplemented with chia at the moment of intake. The results show that theabundance of the main components is correlated with the antioxidant capacity measuredby chemical methods; therefore, the increased antioxidant activity ofsupplemented pasta compared with control wheat pasta is explained by thepresence of phenolic compounds provided by chia, particularly rosmarinic acidand other caffeic acid derivatives.This work represents an interesting contribution in the field,considering that it is the first report with a detailed profile of phenoliccompounds of defatted chia seeds and a derivative food, using HPLC-MS/MSmethodology.