Electrochemical Determination of the “Furanic Index” in Honey
5-(hydroxymethyl)furan-2-carbaldehyde, better known as hydroxymethylfurfural (HMF), is a well-known freshness parameter of honey: although mostly absent in fresh samples, its concentration tends to increase naturally with aging. However, high quantities of HMF are also found in fresh but adulterated...
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MDPI AG
2021-07-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/26/14/4115 |
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| author | Severyn Salis Nadia Spano Marco Ciulu Ignazio Floris Maria I. Pilo Gavino Sanna |
| author_facet | Severyn Salis Nadia Spano Marco Ciulu Ignazio Floris Maria I. Pilo Gavino Sanna |
| author_sort | Severyn Salis |
| collection | DOAJ |
| description | 5-(hydroxymethyl)furan-2-carbaldehyde, better known as hydroxymethylfurfural (HMF), is a well-known freshness parameter of honey: although mostly absent in fresh samples, its concentration tends to increase naturally with aging. However, high quantities of HMF are also found in fresh but adulterated samples or honey subjected to thermal or photochemical stresses. In addition, HMF deserves further consideration due to its potential toxic effects on human health. The processes at the origin of HMF formation in honey and in other foods, containing saccharides and proteins—mainly non-enzymatic browning reactions—can also produce other furanic compounds. Among others, 2-furaldehyde (2F) and 2-furoic acid (2FA) are the most abundant in honey, but also their isomers (i.e., 3-furaldehyde, 3F, and 3-furoic acid, 3FA) have been found in it, although in small quantities. A preliminary characterization of HMF, 2F, 2FA, 3F, and 3FA by cyclic voltammetry (CV) led to hypothesizing the possibility of a comprehensive quantitative determination of all these compounds using a simple and accurate square wave voltammetry (SWV) method. Therefore, a new parameter able to provide indications on quality of honey, named “Furanic Index” (FI), was proposed in this contribution, which is based on the simultaneous reduction of all analytes on an Hg electrode to ca. −1.50 V vs. Saturated Calomel Electrode (SCE). The proposed method, validated, and tested on 10 samples of honeys of different botanical origin and age, is fast and accurate, and, in the case of strawberry tree honey (<i>Arbutus unedo</i>), it highlighted the contribution to the FI of the homogentisic acid (HA), i.e., the chemical marker of the floral origin of this honey, which was quantitatively reduced in the working conditions. Excellent agreement between the SWV and Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC) data was observed in all samples considered. |
| first_indexed | 2024-03-10T09:31:29Z |
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| id | doaj.art-69810c30bb904cdd86a0f6ba3910d6f9 |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-10T09:31:29Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-69810c30bb904cdd86a0f6ba3910d6f92023-11-22T04:28:47ZengMDPI AGMolecules1420-30492021-07-012614411510.3390/molecules26144115Electrochemical Determination of the “Furanic Index” in HoneySeveryn Salis0Nadia Spano1Marco Ciulu2Ignazio Floris3Maria I. Pilo4Gavino Sanna5Istituto Zooprofilattico Sperimentale della Sardegna, Via Duca degli Abruzzi 8, 07100 Sassari, ItalyDipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, ItalyDepartment of Animal Sciences, University of Göttingen, Kellnerweg 6, 37077 Göttingen, GermanyDipartimento di Agraria, Università degli Studi di Sassari, Viale Italia 39/a, 07100 Sassari, ItalyDipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, ItalyDipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, Italy5-(hydroxymethyl)furan-2-carbaldehyde, better known as hydroxymethylfurfural (HMF), is a well-known freshness parameter of honey: although mostly absent in fresh samples, its concentration tends to increase naturally with aging. However, high quantities of HMF are also found in fresh but adulterated samples or honey subjected to thermal or photochemical stresses. In addition, HMF deserves further consideration due to its potential toxic effects on human health. The processes at the origin of HMF formation in honey and in other foods, containing saccharides and proteins—mainly non-enzymatic browning reactions—can also produce other furanic compounds. Among others, 2-furaldehyde (2F) and 2-furoic acid (2FA) are the most abundant in honey, but also their isomers (i.e., 3-furaldehyde, 3F, and 3-furoic acid, 3FA) have been found in it, although in small quantities. A preliminary characterization of HMF, 2F, 2FA, 3F, and 3FA by cyclic voltammetry (CV) led to hypothesizing the possibility of a comprehensive quantitative determination of all these compounds using a simple and accurate square wave voltammetry (SWV) method. Therefore, a new parameter able to provide indications on quality of honey, named “Furanic Index” (FI), was proposed in this contribution, which is based on the simultaneous reduction of all analytes on an Hg electrode to ca. −1.50 V vs. Saturated Calomel Electrode (SCE). The proposed method, validated, and tested on 10 samples of honeys of different botanical origin and age, is fast and accurate, and, in the case of strawberry tree honey (<i>Arbutus unedo</i>), it highlighted the contribution to the FI of the homogentisic acid (HA), i.e., the chemical marker of the floral origin of this honey, which was quantitatively reduced in the working conditions. Excellent agreement between the SWV and Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC) data was observed in all samples considered.https://www.mdpi.com/1420-3049/26/14/4115HMFhoneyfuranic aldehydesfuranic acidshomogentisic acidcyclic voltammetry |
| spellingShingle | Severyn Salis Nadia Spano Marco Ciulu Ignazio Floris Maria I. Pilo Gavino Sanna Electrochemical Determination of the “Furanic Index” in Honey Molecules HMF honey furanic aldehydes furanic acids homogentisic acid cyclic voltammetry |
| title | Electrochemical Determination of the “Furanic Index” in Honey |
| title_full | Electrochemical Determination of the “Furanic Index” in Honey |
| title_fullStr | Electrochemical Determination of the “Furanic Index” in Honey |
| title_full_unstemmed | Electrochemical Determination of the “Furanic Index” in Honey |
| title_short | Electrochemical Determination of the “Furanic Index” in Honey |
| title_sort | electrochemical determination of the furanic index in honey |
| topic | HMF honey furanic aldehydes furanic acids homogentisic acid cyclic voltammetry |
| url | https://www.mdpi.com/1420-3049/26/14/4115 |
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