Evaluation of antioxidant properties of chia seeds (Salvia hispanica) and dehydrated rosehip (Rosa eglateria) extracts for synthetic additive replacement

DOS SANTOS, CRISTINA; BUERA, MARÍA DEL PILAR; MAZZOBRE, MARÍA F.

Lima

Congreso; VIII Congreso Iberoamericano de Ingeniería de Alimentos (CIBIA 8); 2011

The objective of present work was to optimize the experimental conditions for obtaining chia seeds (Salvia Hispanica) and rosehip (Rosa eglanteria) fruit extracts with antioxidant capacity for potential application in replacing synthetic compounds. The use of differential scanning calorimeter (DSC) was particularly evaluated to estimate antioxidant activity. Chia seeds were grinded in liquid nitrogen, defatted and the obtained flour extracted using methanol or ethanol-water mixtures. Rosehip aqueous extract was prepared by stirring the dehydrated fruit in hot water or ethanol. Antioxidant activity was determined by DPPH and by analysing the thermal stability of oils by DSC. Total phenolic compounds were determined by Folin-Ciocalteau. The extraction process was optimized and both chía and rosehip extracts with radical scavenging activity were obtained. Incorporation of chia or rosehip extracts in 0.06 % w/w increased by more than 10ºC the oxidation onset temperatures of the studied oils. DSC measurements were in agreement with DPPH determinations. DSC was a feasible method to study thermal oxidation stability of oils. Extracts with proved antioxidant capacity were obtained both from chia seed and rosehip which could be used for replacing synthetic additives or as functional ingredients in foods.