Hydroxycinnamoyl conjugates in potato tubers : diversity and reactivity upon processing

C.E. Narváez-Cuenca

Research output: Thesisinternal PhD, WU

Abstract

Despite the large amount of reports on the content of the hydroxycinnamic acid (HCA) caffeic acid and its conjugates (HCAcs; chlorogenic acid (ChA, 5-O-caffeoyl quinic acid), crypto-ChA (4-O-caffeoyl quinic acid) and neo-ChA (3-O-caffeoyl quinic acid)), other HCAcs/dihydroxicinnamic acid conjugates (DHCAcs) are rarely described in potato tubers. Furthermore, scarce information has been provided on the fate of phenolic acids when no anti-browning agents, or when the anti-browning agents ascorbic acid and NaHSO3, are used during the preparation of potato juice. This thesis presents a method for the analysis of HCAs/HCAcs/DHCAcs based on RP-UHPLC-DAD-(H)ESI-MSn. This analytical method revealed a total of 78 compounds tentatively identified as HCAs/HCAcs/DHCAcs when several Colombian potato cultivars and a single Dutch cultivar were analysed. The contribution of the less documented HCAcs/DHCAcs ranged from 7.1 to 20.1 % (w/w) of the total HCAs/HCAcs/DHCAcs in whole tuber. We provide for the first time molecular evidence on the formation of sulfonic acid derivatives when potato extracts are prepared in the presence of NaHSO3. In that scenario, no ChA isomers were found but their sulfonic acid conjugates, with 2’-sulfo-ChA being found as the most abundant, followed by 2’-sulfo-crypto-ChA. Based on model experiments it was found that NaHSO3 has a dual anti-browning effect: it reacts with ChA quinone, generated upon oxidation catalysed by polyphenol oxidase (PPO), to produce sulfo-ChA, and it inactivates PPO in a time-dependant way. When no anti-browning agent was used during the preparation of potato juice, the majority of the free ChA present in potato tubers was found to be associated with proteins. These results might explain why potato proteins, used as food ingredient, can turn brown in applications, when the protein is not isolated from potato tubers employing appropriate processing methodology.

 

 

Original languageEnglish
QualificationDoctor of Philosophy
Awarding Institution
  • Wageningen University
Supervisors/Advisors
  • Gruppen, Harry, Promotor
  • Vincken, Jean-Paul, Co-promotor
Award date19 Feb 2013
Place of PublicationS.l.
Publisher
Print ISBNs9789461734914
Publication statusPublished - 2013

Fingerprint

tubers
potatoes
quinic acid
acids
sulfonic acid
catechol oxidase
juices
potato protein
coumaric acids
cultivars
caffeic acid
chlorogenic acid
quinones
phenolic acids
isomers
analytical methods
ingredients
proteins
ascorbic acid
chemical derivatives

Keywords

  • potatoes
  • coumaric acids
  • sodium sulfite
  • browning

Cite this

@phdthesis{42a692fdb9254b3ab65ed8a02caaaad3,
title = "Hydroxycinnamoyl conjugates in potato tubers : diversity and reactivity upon processing",
abstract = "Despite the large amount of reports on the content of the hydroxycinnamic acid (HCA) caffeic acid and its conjugates (HCAcs; chlorogenic acid (ChA, 5-O-caffeoyl quinic acid), crypto-ChA (4-O-caffeoyl quinic acid) and neo-ChA (3-O-caffeoyl quinic acid)), other HCAcs/dihydroxicinnamic acid conjugates (DHCAcs) are rarely described in potato tubers. Furthermore, scarce information has been provided on the fate of phenolic acids when no anti-browning agents, or when the anti-browning agents ascorbic acid and NaHSO3, are used during the preparation of potato juice. This thesis presents a method for the analysis of HCAs/HCAcs/DHCAcs based on RP-UHPLC-DAD-(H)ESI-MSn. This analytical method revealed a total of 78 compounds tentatively identified as HCAs/HCAcs/DHCAcs when several Colombian potato cultivars and a single Dutch cultivar were analysed. The contribution of the less documented HCAcs/DHCAcs ranged from 7.1 to 20.1 {\%} (w/w) of the total HCAs/HCAcs/DHCAcs in whole tuber. We provide for the first time molecular evidence on the formation of sulfonic acid derivatives when potato extracts are prepared in the presence of NaHSO3. In that scenario, no ChA isomers were found but their sulfonic acid conjugates, with 2’-sulfo-ChA being found as the most abundant, followed by 2’-sulfo-crypto-ChA. Based on model experiments it was found that NaHSO3 has a dual anti-browning effect: it reacts with ChA quinone, generated upon oxidation catalysed by polyphenol oxidase (PPO), to produce sulfo-ChA, and it inactivates PPO in a time-dependant way. When no anti-browning agent was used during the preparation of potato juice, the majority of the free ChA present in potato tubers was found to be associated with proteins. These results might explain why potato proteins, used as food ingredient, can turn brown in applications, when the protein is not isolated from potato tubers employing appropriate processing methodology.    ",
keywords = "aardappelen, cumarinezuren, natriumsulfiet, bruinkleuring, potatoes, coumaric acids, sodium sulfite, browning",
author = "C.E. Narv{\'a}ez-Cuenca",
note = "WU thesis 5414",
year = "2013",
language = "English",
isbn = "9789461734914",
publisher = "s.n.",
school = "Wageningen University",

}

Narváez-Cuenca, CE 2013, 'Hydroxycinnamoyl conjugates in potato tubers : diversity and reactivity upon processing', Doctor of Philosophy, Wageningen University, S.l..

Hydroxycinnamoyl conjugates in potato tubers : diversity and reactivity upon processing. / Narváez-Cuenca, C.E.

S.l. : s.n., 2013. 150 p.

Research output: Thesisinternal PhD, WU

TY - THES

T1 - Hydroxycinnamoyl conjugates in potato tubers : diversity and reactivity upon processing

AU - Narváez-Cuenca, C.E.

N1 - WU thesis 5414

PY - 2013

Y1 - 2013

N2 - Despite the large amount of reports on the content of the hydroxycinnamic acid (HCA) caffeic acid and its conjugates (HCAcs; chlorogenic acid (ChA, 5-O-caffeoyl quinic acid), crypto-ChA (4-O-caffeoyl quinic acid) and neo-ChA (3-O-caffeoyl quinic acid)), other HCAcs/dihydroxicinnamic acid conjugates (DHCAcs) are rarely described in potato tubers. Furthermore, scarce information has been provided on the fate of phenolic acids when no anti-browning agents, or when the anti-browning agents ascorbic acid and NaHSO3, are used during the preparation of potato juice. This thesis presents a method for the analysis of HCAs/HCAcs/DHCAcs based on RP-UHPLC-DAD-(H)ESI-MSn. This analytical method revealed a total of 78 compounds tentatively identified as HCAs/HCAcs/DHCAcs when several Colombian potato cultivars and a single Dutch cultivar were analysed. The contribution of the less documented HCAcs/DHCAcs ranged from 7.1 to 20.1 % (w/w) of the total HCAs/HCAcs/DHCAcs in whole tuber. We provide for the first time molecular evidence on the formation of sulfonic acid derivatives when potato extracts are prepared in the presence of NaHSO3. In that scenario, no ChA isomers were found but their sulfonic acid conjugates, with 2’-sulfo-ChA being found as the most abundant, followed by 2’-sulfo-crypto-ChA. Based on model experiments it was found that NaHSO3 has a dual anti-browning effect: it reacts with ChA quinone, generated upon oxidation catalysed by polyphenol oxidase (PPO), to produce sulfo-ChA, and it inactivates PPO in a time-dependant way. When no anti-browning agent was used during the preparation of potato juice, the majority of the free ChA present in potato tubers was found to be associated with proteins. These results might explain why potato proteins, used as food ingredient, can turn brown in applications, when the protein is not isolated from potato tubers employing appropriate processing methodology.    

AB - Despite the large amount of reports on the content of the hydroxycinnamic acid (HCA) caffeic acid and its conjugates (HCAcs; chlorogenic acid (ChA, 5-O-caffeoyl quinic acid), crypto-ChA (4-O-caffeoyl quinic acid) and neo-ChA (3-O-caffeoyl quinic acid)), other HCAcs/dihydroxicinnamic acid conjugates (DHCAcs) are rarely described in potato tubers. Furthermore, scarce information has been provided on the fate of phenolic acids when no anti-browning agents, or when the anti-browning agents ascorbic acid and NaHSO3, are used during the preparation of potato juice. This thesis presents a method for the analysis of HCAs/HCAcs/DHCAcs based on RP-UHPLC-DAD-(H)ESI-MSn. This analytical method revealed a total of 78 compounds tentatively identified as HCAs/HCAcs/DHCAcs when several Colombian potato cultivars and a single Dutch cultivar were analysed. The contribution of the less documented HCAcs/DHCAcs ranged from 7.1 to 20.1 % (w/w) of the total HCAs/HCAcs/DHCAcs in whole tuber. We provide for the first time molecular evidence on the formation of sulfonic acid derivatives when potato extracts are prepared in the presence of NaHSO3. In that scenario, no ChA isomers were found but their sulfonic acid conjugates, with 2’-sulfo-ChA being found as the most abundant, followed by 2’-sulfo-crypto-ChA. Based on model experiments it was found that NaHSO3 has a dual anti-browning effect: it reacts with ChA quinone, generated upon oxidation catalysed by polyphenol oxidase (PPO), to produce sulfo-ChA, and it inactivates PPO in a time-dependant way. When no anti-browning agent was used during the preparation of potato juice, the majority of the free ChA present in potato tubers was found to be associated with proteins. These results might explain why potato proteins, used as food ingredient, can turn brown in applications, when the protein is not isolated from potato tubers employing appropriate processing methodology.    

KW - aardappelen

KW - cumarinezuren

KW - natriumsulfiet

KW - bruinkleuring

KW - potatoes

KW - coumaric acids

KW - sodium sulfite

KW - browning

M3 - internal PhD, WU

SN - 9789461734914

PB - s.n.

CY - S.l.

ER -