Effect of roasting conditions on the antioxidant compounds of quinoa seeds

Abstract

The effect of different roasting conditions on the antioxidant properties and the phenolic content of quinoa seeds was studied. Advanced and final products of the Maillard reaction were also quantified in order to evaluate the contribution to DPPH radical scavenging capacity and reducing power of samples. In general, response surface analysis showed significant increases in the phenolic content, the antioxidant activity and the level of Maillard reaction products (MRPs), mainly as processing temperature increased, while roasting time had a minor impact on these response variables. The highest antioxidant activity was achieved in extracts of quinoa seeds roasted at 190°C for 30 min. Principal component analysis applied to the data suggested that MRPs had a greater contribution to antioxidant properties than phenolic compounds in the processed samples. These results demonstrated that roasted quinoa seeds/flour may be considered as a nontraditional ingredient with enhanced antioxidant capacity for the production of functional foods.

Effect of Germination and Fermentation Process on the Antioxidant Compounds of Quinoa Seeds

“…HPLC Analysis of Phenolic Compounds Reversed phase HPLC method for determination of phenolic acids and flavonoids was carried out with the same HPLC system and the same conditions as has been described in a previous work [13]. The identification of the phenolic compounds was achieved by comparing retention times and UV spectra of the unknown compounds with standards.…”

Cereal processing and glycaemic response

“…Processing temperature and time are also important in toasting, roasting and frying (Roopa & Premavalli, 2008;Carciochi et al, 2016). Like baking, toasting, roasting and frying are usually at high temperatures with the tempered or nontempered grains in direct contact with hot surfaces or media (e.g.…”

“…For example, high-amylose cereal products, a grain factor, have a low GI (Hung et al, 2016;Kaur et al, 2016), and the presence of certain micronutrients (e.g. There are many cereal products from diverse processing techniques, and their properties, including starch digestibility, resistant starch and GI, are dependent on the attendant heat, moisture, mechanical and biotechnological effects of the processing techniques (Brennan et al, 2013;Wolter et al, 2014;Taylor et al, 2015;Carciochi et al, 2016;Hassani et al, 2016). There are many cereal products from diverse processing techniques, and their properties, including starch digestibility, resistant starch and GI, are dependent on the attendant heat, moisture, mechanical and biotechnological effects of the processing techniques (Brennan et al, 2013;Wolter et al, 2014;Taylor et al, 2015;Carciochi et al, 2016;Hassani et al, 2016).…”

Effect of malting conditions on phenolic content, Maillard reaction products formation, and antioxidant activity of quinoa seeds

“…190°C, respectively). These temperatures and times were chosen according to results of our previous study using raw quinoa seeds (Carciochi et al 2016). After roasting, malted quinoa was allowed to cool to ambient temperature in a desiccator and used for further analysis.…”

“…Aqueous extraction of MRPs was performed according to a previous work (Carciochi et al 2016). Analysis of available fluorescence intermediary compounds (FIC) and final MRPs (melanoidins) were performed according to the methods described by Michalska et al (2008).…”