A first pilot study to produce a food antioxidant from sunflower seed shells ( Helianthus annuus )

Abstract

A first pilot study to produce a food antioxidant from sunflower seed shells (Helianthus annuus)This article explains a laboratory procedure to produce an antioxidant from grinded, dehulled and partially defatted sunflower seeds. Initially, a solvent suitable to extract phenols was searched among different solutions of water mixed with ethanol, methanol and acetone at 40% (vol/vol) (each tested at pH 5, 7 and 9). Both the ethanol/water 60:40 (vol/vol) and the acetone/water 60:40 (vol/vol) mixtures proved to be suitable for the dephenolization of sunflower seed shells, but in the next steps of this research, the mixture ethanol/water 60:40 (vol/vol) at pH 5 was used. Secondly, the procedure to obtain the antioxidant product was defined, which consisted in hydrolysis of sunflower seed phenols with 1.25 N NaOH at room temperature for 60 min and finally the recovery of caffeic acid formed from chlorogenic acid with ethyl acetate. From 25 g of partially defatted sunflower shells, around 90 mg of powdery antioxidant product, consisting of 58% caffeic acid, was obtained. The antioxidant product, the caffeic acid standard and propyl gallate were added to different edible fats at the same dose of 240 AU (antioxidant units) per kg fat. A Rancimat test, at 130 7C and an air flow of 20 L h 21 , demonstrated that the effectiveness of the sunflower antioxidant product was essentially similar to that of the caffeic acid standard, but 15-20% lower than that of propyl gallate. In conclusion, dephenolization of sunflower seeds could be economically convenient, not only because a useful antioxidant can be produced, but also because the raw material composition can be improved for other uses.

The Practical Application of Sunflower Meal in Poultry Nutrition

“…Irrespective of CGA, SFM contains other phenolic compounds such as caffeic, rosmarinic and ferulic acids, as well as myricetin and rutin, all these compounds present in quantities of less than 0.15 ppm. De Leonardis et al (2005; reported that phenolic compounds of SFS included seven molecules like chlorogenic, caffeic, protocatechuic, o-cinnamic, ferulic and syringic acids. CGA is a phytochemical molecule which is the ester of caffeic acid (CA) and quinic acid (QA).…”

Potential application of oilseeds as sources of antioxidants for food lipids - a review

“…Peanut hulls (skins) are a particularly rich source of phenolics, containing tannins, procyanidins, catechin and epicatechin oligomers, resveratrol, and other phenolic substances (KARCHESY & HEMMINGWAY 1986). Sunflower seed shells are rich in chlorogenic acids; caffeic acid can be isolated from the aqueous-ethanolic extract after saponification (DELEONARDIS et al 2005). Hazelnut hulls contain high concentrations of phenolics (MOURE et al 2003).…”

Antioxidant activity of phenolic compounds identified in sunflower seeds

“…The antioxidant compounds are present in both sunflower oil and oilseed-extracted meal [5]. Extracts with high antioxidant activity may also be obtained from sunflower seed shells [6,7]. Compared to vegetables oils, sunflower oil is especially rich in a-tocopherol [5].…”

“…Compared to vegetables oils, sunflower oil is especially rich in a-tocopherol [5]. The antioxidant potential of defatted sunflower meal and sunflower seed shells is determined mainly by the content of phenolic compounds [5,6]. However, it has to be mentioned that shells contain only 0.7-5.4 % of sunflower seed phenolics, whereas the rest is located in kernels [8].…”