From nutritive seeds to complex foods: Markers of composition and stability along the food-production chain. Case study: Chia (Salvia hispanica L.), flax (linseed; Linum usitatissimum), sesame (Sesamum indicum) and bakery products containing these seeds.

BARONI, M.V.; PERAL-GARCIA, P.; PASIK, DIEGO; KOPKA, J.; ERBAN, A.; WUNDERLIN, D.A.

Parma

Conferencia; Assuring the integrity of the food chain: Turning Science into Solutions.; 2017

FERA

Nowadays, there is a widespread preference for theconsumption of foods that, in addition to its nutritional properties, providecomponents that could reduce the risk of certain diseases, leading to theconcept of "functional food". Chia, flax and sesame seeds are a great source ofpolyphenols and have greatly increased their popularity among consumers due totheir beneficial properties like reducing cancer risk, diabetes and heartdisease, among others. The antioxidant activity shown by these compounds is responsibleof the mentioned properties. Due to their great nutritionalcapacity, these seeds can be added to processedfoods to increase their nutritional value.Food integrity is the state of being whole, complete,undiminished or in perfect state in terms of quantity and quality, and thisquality means to reach specific standards in sensory, microbiological andorigin aspects of foodstuffs. There is a gap in the availablescientific information to evaluate food attributes for complex foods. Manytimes it is difficult to assess the presence of a particular ingredient ofnutritional importance within a complex food. So far, when a food product canbe sold for a premium price because of its characteristics, it is of paramountimportance that label claims and declarations on origin and identity can becertified.The aim of this work was to find polyphenolswithin each seed, which could be used as authenticity biomarkers in complexfoods contaning these seeds.For this study we used defatted chia, flax and sesameflour obtained after oil extraction. Polyphenols were extracted by sonicationof defatted flour with ethanol 50% and identified and quantified by liquidchromatography coupled with time of flight mass spectrometry detection(HPLC-ESI-qTOF). The identification was done by MSn spectra, UV-Visspectra and exact mass comparison and quantification was performed by externalcalibration curves using structurally related compounds.Nineteen polyphenols were found in the sesame flour,of which eleven were lignans (derivatives of Enterolactone and Enterodiol),five phenolic acids (being these the majority ones); and only three flavonoids whichwere (-)-Epigallocatechin-3-O-gallate,Apigenin, Apigenin-6-C-glucoside.On the other hand, fourteen compounds were found inchia flour and all of them were phenolic acids being the majority derived fromCaffeic acid (e.g. Salviaflaside and Rosmarinic acid).Finally, fifteen compounds were found in flax flour, sixwere phenolic acids (mainly Caffeic acid derivatives such as O-caffeoyl-fructosyl-glucoside andRosmarinic acid hexoside), one was Quinic acid and eight were flavonoidsderived from Quercetin mostly.There were ubiquitous compounds inthe analyzed seeds such as Rosmarinic acid and Quinic acid. On the other hand,each seed showed distinctive compounds. In the case of sesame flour the lignans(e.g. Sesamolin, 7-Hydroxymatairesinol, Matairesinol-rhamnoside); in the caseof the flax flour the flavonoids (Cyanidin-3-O-glucoside, Eriodictyol-7-O-glucoside,Gallocatechin, among others) and in the case of chia some phenolic acids like Caftaricacid, Fertaric acid, Salvianolic acids, Sagerinic acid and Danshensu.Therefore, these key polyphenolscould be used to differentiate each seed as well as markers of authenticity in complexfoods. Further research is needed to evaluate the stability of these proposedmarkers after food processing.