Microwave Pretreatment for the Extraction of Anthocyanins from Saffron Flowers: Assessment of Product Quality

The potential of saffron flowers as a source of polyphenols, and in particular anthocyanins, for the extraction of bioactive compounds and the production of a cyanic colorant was analyzed. A microwave pretreatment, prior to the conventional solid–liquid extraction process, was proposed as a feasible...

Full description

Bibliographic Details
Main Authors: Ana Álvarez, Sara Terreros, María J. Cocero, Rafael B. Mato
Format: Article
Language:English
Published: MDPI AG 2021-06-01
Series:Antioxidants
Subjects:
Online Access:https://www.mdpi.com/2076-3921/10/7/1054
id doaj-19a22328b2c143f2bfb8e9030ab61b17
record_format Article
spelling doaj-19a22328b2c143f2bfb8e9030ab61b172021-07-23T13:28:36ZengMDPI AGAntioxidants2076-39212021-06-01101054105410.3390/antiox10071054Microwave Pretreatment for the Extraction of Anthocyanins from Saffron Flowers: Assessment of Product QualityAna Álvarez0Sara Terreros1María J. Cocero2Rafael B. Mato3BioEcoUva, Research Institute on Bioeconomy, High Pressure Processes Group, Department of Chemical Engineering and Environmental Technology, University of Valladolid, 47011 Valladolid, SpainBioEcoUva, Research Institute on Bioeconomy, High Pressure Processes Group, Department of Chemical Engineering and Environmental Technology, University of Valladolid, 47011 Valladolid, SpainBioEcoUva, Research Institute on Bioeconomy, High Pressure Processes Group, Department of Chemical Engineering and Environmental Technology, University of Valladolid, 47011 Valladolid, SpainBioEcoUva, Research Institute on Bioeconomy, High Pressure Processes Group, Department of Chemical Engineering and Environmental Technology, University of Valladolid, 47011 Valladolid, SpainThe potential of saffron flowers as a source of polyphenols, and in particular anthocyanins, for the extraction of bioactive compounds and the production of a cyanic colorant was analyzed. A microwave pretreatment, prior to the conventional solid–liquid extraction process, was proposed as a feasible intensification step. The effectiveness of microwave pretreatment was assessed in terms of increased yield and improved quality of the final product. The operational variables studied were the pretreatment temperature (60–120 °C) and the solid–liquid ratio (0.30–0.50 g/mL). It was found that the addition of the microwave pretreatment to the conventional process allowed one to reduce extraction time by up to 12 times and to greatly improve the characteristics of the final product, using microwave energy densities as low as 0.16–0.54 kJ/mL. The extract quality was evaluated in terms of polyphenol richness (25% increase), product composition (80% of the anthocyanins was delphinidin), antioxidant capacity (boosted by the pretreatment) and color (variations in red and blue hue depending on conditions). To conclude, a microwave pretreatment in which the material is heated to a temperature of 65 °C with a solvent ratio of 0.30 g/mL was selected as the optimum to maximize process efficiency and product quality.https://www.mdpi.com/2076-3921/10/7/1054saffron flowersmicrowave pretreatmentsolid–liquid ratiokinetic analysiscolor
collection DOAJ
language English
format Article
sources DOAJ
author Ana Álvarez
Sara Terreros
María J. Cocero
Rafael B. Mato
spellingShingle Ana Álvarez
Sara Terreros
María J. Cocero
Rafael B. Mato
Microwave Pretreatment for the Extraction of Anthocyanins from Saffron Flowers: Assessment of Product Quality
Antioxidants
saffron flowers
microwave pretreatment
solid–liquid ratio
kinetic analysis
color
author_facet Ana Álvarez
Sara Terreros
María J. Cocero
Rafael B. Mato
author_sort Ana Álvarez
title Microwave Pretreatment for the Extraction of Anthocyanins from Saffron Flowers: Assessment of Product Quality
title_short Microwave Pretreatment for the Extraction of Anthocyanins from Saffron Flowers: Assessment of Product Quality
title_full Microwave Pretreatment for the Extraction of Anthocyanins from Saffron Flowers: Assessment of Product Quality
title_fullStr Microwave Pretreatment for the Extraction of Anthocyanins from Saffron Flowers: Assessment of Product Quality
title_full_unstemmed Microwave Pretreatment for the Extraction of Anthocyanins from Saffron Flowers: Assessment of Product Quality
title_sort microwave pretreatment for the extraction of anthocyanins from saffron flowers: assessment of product quality
publisher MDPI AG
series Antioxidants
issn 2076-3921
publishDate 2021-06-01
description The potential of saffron flowers as a source of polyphenols, and in particular anthocyanins, for the extraction of bioactive compounds and the production of a cyanic colorant was analyzed. A microwave pretreatment, prior to the conventional solid–liquid extraction process, was proposed as a feasible intensification step. The effectiveness of microwave pretreatment was assessed in terms of increased yield and improved quality of the final product. The operational variables studied were the pretreatment temperature (60–120 °C) and the solid–liquid ratio (0.30–0.50 g/mL). It was found that the addition of the microwave pretreatment to the conventional process allowed one to reduce extraction time by up to 12 times and to greatly improve the characteristics of the final product, using microwave energy densities as low as 0.16–0.54 kJ/mL. The extract quality was evaluated in terms of polyphenol richness (25% increase), product composition (80% of the anthocyanins was delphinidin), antioxidant capacity (boosted by the pretreatment) and color (variations in red and blue hue depending on conditions). To conclude, a microwave pretreatment in which the material is heated to a temperature of 65 °C with a solvent ratio of 0.30 g/mL was selected as the optimum to maximize process efficiency and product quality.
topic saffron flowers
microwave pretreatment
solid–liquid ratio
kinetic analysis
color
url https://www.mdpi.com/2076-3921/10/7/1054
work_keys_str_mv AT anaalvarez microwavepretreatmentfortheextractionofanthocyaninsfromsaffronflowersassessmentofproductquality
AT saraterreros microwavepretreatmentfortheextractionofanthocyaninsfromsaffronflowersassessmentofproductquality
AT mariajcocero microwavepretreatmentfortheextractionofanthocyaninsfromsaffronflowersassessmentofproductquality
AT rafaelbmato microwavepretreatmentfortheextractionofanthocyaninsfromsaffronflowersassessmentofproductquality
_version_ 1721289675202625536