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Trends in Food Science & Technology 17 (2006) 97–104
Review
Pectin: new insights
into an old polymer
are starting to gel
William G.T Willatsa*, J.
Paul Knoxb and Jørn
Dalgaard Mikkelsenc
a
&
The Department of Plant Physiology, The University
of Copenhagen, Øster Farimagsgade 2A, DK-1353
Copenhagen K, Denmark.
(Tel.: C45 35322132; fax: C45 35322128;
e-mail: [email protected])
b
Centre for Plant Sciences. University of Leeds,
Leeds LS2 9JT, U.K.
c
Danisco Biotechnology, Langebrogade 1, DK-1001
Copenhagen K, Denmark
Pectin is a high value functional food ingredient widely used
as a gelling agent and stabilizer. It is also an abundant,
ubiquitous and multifunctional component of the cell walls
of all land plants. Food scientists and plant scientists
therefore share a common goal to better understand the
structure and functionalities of pectic polymers at the
molecular level. The basic properties of pectin have been
known for nearly 200 years, but recently there has been
tremendous progress in our understanding of the very
complex fine structure of pectic polymers and pectinolytic
enzymes. This has been made possible by synergies between
plant and food research and by the application of a range of
state-of-the-art techniques including enzymatic fingerprinting, mass spectrometry, NMR, molecular modelling, and
monoclonal antibodies. With this increased knowledge
comes the prospect of novel applications. Producers are
beginning to develop a new generation of sophisticated
designer pectins with specific functionalities. Moreover, the
ability to manipulate pectin in planta would have a major
impact on fruit and vegetable quality and processing, as well
as on pectin production.
* Corresponding author.
0924-2244/$ - see front matter q 2005 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tifs.2005.10.008
Introduction
Pectin is all around us. It is a major component of the
cell walls of all land plants and in a normal western diet
around 4–5 g of pectin are consumed each day (Pilnik,
1990). Extracted pectin is widely used as functional food
ingredient and it (or its EU code, E440) is listed among
the ingredients of innumerable food products. Worldwide
annual consumption is estimated at around 45 million
kilograms, with a global market value of at least 400
million Euros (Savary, Hotchkiss, Fishman, Cameron, &
Shatters, 2003). The gelling properties of pectin, that are
well known to home jam makers and industrial producers
alike, were first described by Hennri Braconnot in 1825
(Braconnot, 1825). In his excellent review, W. Pilnik
describes how Braconnot coined the name pectin, derived
from the Greek phctos ‘pektikos’ meaning to congeal
or solidify. Braconnot also predicted that it would have
important functions in all plants and have many
applications in the art of the ‘confiseur’ (Braconnot,
1825). On all points he was quite correct and the study
of this remarkable macromolecule has been pursued
vigorously by both plant and food scientists ever since.
In the food industry pectin is known primarily as a
gelling agent and is widely used in the production of
jams and jellies, fruit juice, confectionary products and
bakery fillings (May, 1997; Rolin & De Vries, 1990).
The other major use of pectin is for the stabilisation of
acidified milk drinks and yogurts. In all application
areas the fine structure of pectin profoundly affects its
functionality. This is reflected in the fact that although
most plant tissues contain pectin, commercial production
is based almost entirely on just a few sources that have
the required properties (Thakur, Singh, & Handa, 1997).
Currently, citrus peel and apple pomace are the major
sources of extracted pectin whilst other potentially
valuable sources remain largely unused because of
certain undesirable structural properties.
This close relationship between structure and function
has motivated research into a better understanding of pectin
structure with the eventual aim of refining the production
process. It is envisaged that new ‘designer pectins’ with
bespoke functionalities may be produced. This can be
achieved to some extent by the rational modification of
extracted pectin by chemical or enzymatic treatment. A
more ambitious goal is to modify pectin structure within
plants before extraction—thus the manufacture of
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W.G.T. Willats et al. / Trends in Food Science & Technology 17 (2006) 97–104
commercial pectin may start with the manipulation of plant
genes rather than with fruit pulp.
Several reviews have described the structure, processing
and applications of pectin (Pilnik, 1990; May, 1997; Rolin
& De Vries, 1990). The purpose of this article is to highlight
some of the most recent advances in pectin research from
both plant and food science, and to discuss the consequences
for pectin production and application.
New insights into pectin structure
The term ‘pectin’ is a somewhat misleading since it
rather implies one molecule. In fact pectin describes a
family of oligosaccharides and polysaccharides that have
common features, but are extremely diverse in their fine
structures (Ridley, O’Neill & Mohnen, 2001). However, all
pectins are rich in galacturonic acid (GalA), and the FAO
and EU stipulate that ‘pectin’ must consist of at least 65%
GalA. Three major pectic polysaccharides are recognised,
all containing GalA to a greater or lesser extent.
Homogalacturonan (HG) is a linear polymer consisting of
1,4-linked a-D-GalA, whilst rhamnogalacturonan I (RGI)
consists of the repeating disaccharide [/4)-a-D-GalA(1/2)-a-L-Rha-(1/] to which a variety of different
glycan chains (principally arabinan and galactan) are
attached to the Rha residues. The confusingly named
rhamnogalacturonan II (RGII) has a backbone of HG rather
than RG, with complex side chains attached to the to the
GalA residues (Ridley et al., 2001; Willats, McCartney,
Mackie & Knox, 2001a). Until recently it was accepted that
rhamnogalacturonan and homogalacturonan domains constitute the ‘backbone’ of pectic polymers as shown in
Fig. 1(A). However, an alterative structure has recently been
proposed in which HG is a long side chain of RGI
(Fig. 1(B)) (Vincken et al., 2003). One thing that is not
disputed is that pectins are an extremely complex and
structurally diverse group of polymers. The fine structures
of pectins can be extremely heterogeneous between plants,
between tissues, and even within a single cell wall. The
chain lengths of the various domains can vary considerably,
and the sugar composition of RGI can also be highly
heterogeneous. In contrast, RGII is thought to have a highly
conserved structure. Moreover, GalA in HG may be both
methyl-esterified and acetylated. Both the degree of methylesterification (DE) and degree of acetylation (DA) have a
profound impact on functional properties and pectins are
traditionally categorised as high-ester or low-ester with DEs
of O50% an !50% respectively (Rinaldo, 1996; Voragen,
Pilnik, Thibault, Axelos & Renard, 1995).
A pectin gel is formed when portions of HG are crossedlinked to form a three dimensional crystalline network in
which water and solutes are trapped (Fig. 2(B)). Various
factors determine gelling properties including temperature,
A
Homogalacturonan
Rhamnogalacturonan II
Rhamnogalacturonan I
B
Acetyl ester
Methyl ester
Galacturonic acid (GalA)
Rhamnose (Rha)
Apiose (Api)
Fucose (Fuc)
Aceric acid (AceA)
Galactose (Gal)
Arabinose (Ara)
Xylose (Xyl)
Glucuronic acid (GlcA)
Deoxylyxoheptulopyranosylaric acid (Dha)
Ketodeoxymannooctulopyranosylonic acid (KDO)
Fig. 1. The basic structure of pectin. Schematic representations of the conventional (A) and recently proposed alternative (B) structures of pectin.
It is important to note that the polymers shown here are intended only to illustrate the some of the major domains found in most pectins rather
than definitive structures.
W.G.T. Willats et al. / Trends in Food Science & Technology 17 (2006) 97–104
Fig. 2. Structure function relationships of pectin gels. (A)
Citrus fruits are one of the most important sources of
commercial pectin, and shown here are some of the
commercial products, jams, jellies, fruit gums and acidified
milk drinks manufactured by Danisco A/S using pectin
extracted from limes. (B) Pectin gels are formed when HG
domains are joined at junction zones, forming a crystalline
network that traps water and other molecules. (C) An
extensive series of pectins was produced by de-methylesterification of a high-ester sample (E81) using PMEs from
orange (P-series), Aspergillus niger (F-series) and base
(NaOH, B-series). This figure only shows a subset of the
samples produced and described in Limberg et al., 2002.
Underlined numbers indicate DE. Fungal PMEs generally have
non-blockwise action patterns, producing HG with dispersed
arrangement of methyl-esters along the HG chain. In
contrast, plants PMEs usually have a blockwise action
pattern, producing long stretches (or ‘blocks’) of un-esterified
HG. Treatment with base produces a more random
distribution of methyl-esters. The critical effect of methylester distribution pattern is shown by compression testing of
lime pectin/calcium gels. (D) Two gels with similar degrees,
but different patterns of methyl-esterification were produced
from pectin samples P41 and F43. (E) Both gels were
compressed to yield point but failed in very different ways.
Gels made from P41 were brittle and failed due to cracks
(not visible) running vertically through the gel. In contrast,
F43 gels deformed in a more plastic fashion.
99
pectin type, DE, DA, pH, sugar and other solutes, and
calcium. In high-ester pectins the junction zones are formed
by the cross-linking of HG by hydrogen bridges and
hydrophobic forces between methoxyl groups, both
promoted by high sugar concentration and low pH.
In low-ester pectins junction zones are formed by
calcium cross-linking between free carboxyl groups. It is
increasingly apparent that the pattern of methyl-esterification is also critical in determining rheological properties and
new molecular tools allow us to study methylation patterns
in ever more detail (Section 3). In a recent study, a series of
lime pectin samples was produced from a single highly
methyl-esterified mother pectin sample with a DE of 81%
(E81). Fungal and plant pectin methyl-esterases (PMEs)
were then used to de-methyl-esterify E81 and to generate a
population of pectin samples with a range of DEs and
patterns of methyl-esterification (Willats et al., 2001b;
Limberg, Korner, Buchholt, Christensen, Roepstorff, &
Mikkelsen, 2000; Korner, Limberg, Christensen, Mikkelsen
& Roepstorff, 1999) (Fig. 2(C)). This series of well defined
samples has provided a wealth of information about the
functional implications of methylation patterns. One
example is illustrated in Fig. 2(D) in which two lime pectin
samples with almost the same DE, but different methyl-ester
distribution patterns were subjected to compression testing
and found to have dramatically different rheological
properties.
Plants can teach us a lot about the modulation of
pectin structure, and the fine tuning of HG domains in
particular. In most plant cells, pectin is initially
synthesised in a highly methyl-esterified form but
subsequently de-methyl-esterified in muro by a battery
of PMEs in order to achieve required functionalities
within individual cell walls. The importance of this
process is illustrated by the model plant species
Arabidopsis thaliana which has at least 50 genes
encoding PMEs with diverse action pattern activities
(Willats et al., 2001b. Catoire, Pierron, Morvan, Hervé
du Penhoat & Goldberg, 1998).
Molecular tools for pectin research
There are many well established methods of assessing
the performance of pectins in food matrices. Several recent
advances in pectin analysis now make it possible to relate
these findings in great detail to pectin structure.
Monoclonal antibodies (mAbs) are widely used for the
analysis of pectin in plant science because they allow
defined structural domains to be precisely localised in the
context of intact cell wall architecture. Such antibodies are
now also being used for the analysis of food matrices. As
with plant cell walls, their unique feature is that they can
provide information about interactions between pectin and
other food components in situ. Frozen sample preparation
techniques and sub-zero microscopy even allow liquid and
W.G.T. Willats et al. / Trends in Food Science & Technology 17 (2006) 97–104
100
LM6
A
LM8
LM5
LM7
JIM7
JIM5
2F 4
~30 GalA
Ca2+ Ca2+ Ca2+
PAM1
LM8 Anti-xylogalacturonan
LM6 Anti-arabinan
LM5 Anti-galactan
LM7 Anti-homogalacturonan
JIM5 Anti-homogalacturonan
JIM7 Anti-homogalacturonan
2F4 Anti-homogalacturonan
PAM1 Anti-homogalacturonan
5)
Willats, W.G.T. et al. (2000) Planta 218, 673-681
Willats et al. (1998) Carbohydrate Res. 308(1–2),149-152
Jones, L. et al. (1997) Plant Physiol. 113, 1405–1412
Willatset al. (2001) J. Biol. Chem. 276(22), 19404–19413
Clausenet al. (2003) Carbohydrateres. 338(17), 1797–1800
Clausenet al. (2003) Carbohydrateres., 338(17), 1797–1800
Liners et al. (1989) Plant Physiol. 91, 1419–1424
Willats et al. (1999) Plant J. 18(1), 57-65
GA
(L
PA
ti-X
an
an
ti-H
G(
G(
ti-H
an
M8
M1
7)
JIM
n(
cta
ala
ti-g
an
)
)
LM
B
DE (%):
81
66
41
Lime
16
58
Pectin
31
series
19
64
15
0
(1 4)- -D-gal(4) - BSA
Xylogalacturonan
Galactan
Fig. 3. Anti-pectin antibodies. (A) Antibodies (mAbs) have now been produced against many of the structural domains found in pectic
polymers and the names, epitopes and references of some widely used mAbs are shown. (B) Pectin microarrays combine high-throughput
robotic spotting technology with the specificity of antibodies. In this example, a series of lime pectins and pectin oligomers were spotted
onto polystyrene slides. The slides were probed with anti-pectin antibodies which were then detected using a fluorescent secondary
antibody (Clausen, Willats & Knox, 2003).
semi-liquid systems to be sections and probed with mAbs.
In recent years the number of anti-pectin antibodies has
increased significantly and mAbs with specificities for
numerous side chain and backbone domains are now
available (Fig. 3(A)) (Willats, McCartney & Knox, 2003).
Of particular relevance for the food industry are a set of
antibodies that bind to HG domains. LM7, JIM7 and JIM5
all bind to partially methyl-esterified HG, but have different
specificities with respect to degree and pattern of methylesterification. In contrast, the epitope recognized by PAM1
consists of long stretches of un-esterified HG whilst 2F4
binds specifically to HG that is crossed linked via calcium
(Willats et al., 2001a. Liners, Letesson, Didembourg & Van
Cutsem, 1989). The epitope structures of JIM5, JIM7, LM7
and PAM1 have been characterised in detail over recent
years, including by the use of a series of chemically
synthesised partially methyl-esterified oligogalacturonides
(Clausen, Willats & Knox, 2003). Even high throughput
microarray technologies are now being applied to pectin
research. Microarrays of pectic polymers have been created
using novel activated polymer slides to which diverse
polysaccharides can be immobilised without prior derivitisation (Willats, Rasmussen, Kristensen, Mikkelsen & Knox,
2000) (Fig. 3(B)). The slides were developed for anti-pectin
antibody characterisation, but are now also being used for
the high throughput analysis of the interactions between
pectin and other food matrix components such as caseins.
Enzymatic fingerprinting is a powerful technology that
W.G.T. Willats et al. / Trends in Food Science & Technology 17 (2006) 97–104
A
E81
F76
F69
F5 8
101
F3 1
F43
20
mAU
15
10
5
0
–5
4
5
6
7
8
9
10
11
12
Minutes
B
PC3
1.0
Bi-plot
P60
P70 P65
P46 DE
P73
Gal
Rha P53 Transpo rt Ca
P76
Ar a P41
B71
Activi ty Ca
0.5
0
–0.5
PGA
F11
%GalA in alcohol
Insoluble frac tion
B43
%Dry mat ter
%GalA
B15
pH in 1% so lu ti on
E81
F31
Gyration radio
B64
F76
F43 F58 F69
Conduc tivi ty
Charge dens ity
Visco sit y
Gal A
MW mo l/g
MW Dalto n
B34 PC2
–1.0
–0.8
–0.6
–0.4
–0.2
0
0.2
0.4
0.6
0.8
1.0
Fig. 4. State of art tools for pectin analysis. (A) High performance capillary electrophoresis of a series of model lime pectins (described in 2C)
The mobility of the pectin samples was strongly correlated to DE the width of the peak indicates the heterogeneity of the sample molecule.
(B) Chemometrics is an important new tool for the analysis of pectin using multivariate principles. A series of model pectins (black circles, see
also Fig. 2(C)) were subjected to a variety of different analyses (red diamonds). Principle component analysis (PCA) was used to evaluate the
relationship between the functional and physical properties.
involves the enzymatic digestion of pectin using enzymes
with well defined cleavage specificities, and the subsequent
detailed analysis of the resulting oligomers using chromatography and/or mass spectrometry (MS) (Limberg, Korner,
Buchholt, Christensen, Roepstorff & Mikkelsen, 2000.
Korner et al., 1999. Korner, Limberg, Mikkelsen &
Roepstorff, 1998) (Fig. 2(C)). Furthermore, analysis of
GalA oligomer fragments using electron spray ionisation
MS it is possible to define the methyl-esterification patterns
of each oligomer. Another promising novel technology of
pectin analysis is capillary electrophoresis, as shown in
Fig. 4(A), this is an effective method for separating
population of pectins with different methylation states
(Goubet, Ström, Dupree & William, 2005). These ‘pectinomics’ techniques add to our understanding of pectin
structure, but some may in the future have more direct roles
in pectin production, for example for ‘in-line’ analysis or for
assessing the properties of starting pulps. As with all ’omics
technologies it is sometimes difficult to extract the most
relevant information. Chemometrics is a powerful and novel
approach for combining and analysing large amounts of
data, and is now being applied to pectin research. (Cerna
et al., 2003). We have analysed more than 20 model lime
pectin (see also Fig. 2(C)) and commercial pectin samples
using a variety of methods including fourrier-transformed
infrared spectroscopy (FT-IR), FT-RAMAN and near
infrared resonance, enzymatic fingerprinting, Ion-Trap-MS
and MALDI-TOF, capilary electrophorhesis, and a range of
chemical composition analyses. A number of functional
assays of the same pectins were also performed such as gel
forming properties with calcium, viscosity, ion transport
parameters and calcium activity coefficients, conductivity,
and stabilization of proteins at low pH. As shown in
Fig. 4(B), these data were combined using principal
component analysis (PCA). This kind of analysis is proving
useful in relating knowledge at the molecular level to a
functional properties.
Pectin biosynthesis and modification—towards
in planta manipulation
Advances in our understanding of pectin biosynthesis
and modification are of importance to the food industry for
W.G.T. Willats et al. / Trends in Food Science & Technology 17 (2006) 97–104
102
two reasons. First, native pectin in plant cell walls plays as
central role in the ripening, texture, and storage qualities of
fruits and vegetables. Second, a fuller understanding of the
molecular basis of biosynthesis and modification may allow
us to influence pectin quality and functionalities in planta
even before extraction begins. Several studies have
demonstrated that polygalacturonase (PG) and PME activity
can be reduced using an antisense approach (Brummell &
Harpster, 2001). In one study, tomato fruits were produced
with reduced expression of both a PG gene (LePG) and a
gene encoding an expansin cell wall structural protein
(LeExp1). These fruits were found to be significantly firmer
during ripening and were less susceptible to deterioration
during long term storage (Kalamaki, Harpster, Palys,
Labavitch, Reid & Brummell, 2003). It is also possible to
transgenically manipulate the side chains of pectin.
Expression of an RGI degrading lyase in potato resulted
in significantly reduced levels of arabinan and galactan in
the tubers which also had altered biophysical properties
(Oomen et al., 2002. Ulvskov et al., 2004).
In principle, pectin structure could also be modulated by
manipulation of the glycosyl transferase (GT) enzymes
responsible for joining together the monosaccharides in
pectic polymers. However, the identification of GTencoding genes has proved to be extremely difficult.
Based on our current understanding of the structure of the
pectic matrix, at least 53 GTs must be involved in its
construction, but only two have so far been identified at the
genetic level, a putative HG synthase (Qua1) and a putative
glucuronosyltransferase involved in RGII synthesis
(AtGut1) (7, Mohnen, 1999. Bouton et al., 2002. Iwai,
Masaoka, Ishii & Satoh, 2002). The identification and
characterization of the genes involved in the assembly of all
three cell wall polymer systems therefore remains a major
challenge for plant science. This area of research also has
practical relevance for pectin producers. An example is
illustrated by the recent ‘EuroPectin’ European Framework
V programme aimed at improving sugar beet pectin by gene
manipulation. Sugar beet pulp is potentially an abundant
and low cost source of pectin, but is rarely utilised because
its high DA adversely affects functionality. However,
identification and characterisation of plant acetyl-transferases and esterases may in the future lead to production of
pectin with improved functionality from transgenic sugar
beet.
Pectin and health
The health effects of pectin are receiving increasing
interest. It is generally accepted that a high fibre diet is
beneficial to health and pectin is an important soluble fibre
component of fruits and vegetables. There is clear evidence
that pectin can lower cholesterol levels, serum glucose
levels and may also have anti-cancer activities (Yamada,
A
B
Casein
Pectin
C
Apple pectin
Citrus pectin 1
40
Citrus pectin 2
30
Citrus pectin 3
20
10
E 12
% Sediment
% Sediment
D 50
Citrus pectin
Experimental
10
8
6
4
2
0
0
0
0.1
0.2
0.3
0.4
Pectin concentration (%)
0.5
0
0.05
0.1
0.15
0.2
Pectin concentration (%)
Fig. 5. Pectin and milk stabilistion. (A) The stabilization of acidified milk drinks is one of then most important applications of commercial pectin
and the sedimentation that occurs without pectin is clearly seen. (B) Sedimentation occurs due to the aggregation of casein. (C) When pectin is
added, it is thought that HG domains electrostatically binds to casein particles, thereby preventing clumping and sedimentation. The degree
and pattern of methyl esterification are important in determining the effectiveness of pectins for stabilization. (D) The activity of a set of standard
pectins from apple and citrus is shown, where citrus pectin 3 is the most effective at stabilizing drinking yoghurt. (E) A novel experimental pectin
product was selected by testing a range of lime pectin samples with different degrees and patterns of methyl-esterification. It was found that
PMEs that produced pectin with long un-esterified blocks that were most effective at preventing sedimentation at low concentrations.
W.G.T. Willats et al. / Trends in Food Science & Technology 17 (2006) 97–104
103
1996. Behall & Reiser, 1986). Pectin and pectic oligosaccharides have been shown to induce apoptosis in human
colonic adenocarenoma cells (Olano-Martin, Rimbach,
Gibson & Rastall, 2003). Most studies have involved
relatively crude pectin preparations containing a large
number of different structural domains. It has therefore
been impossible to causally relate specific health related
activities to defined molecular structures. However, new
techniques for pectin analyses, some of which are described
above, are likely to make this possible soon. Importantly,
advances in chromatographic separation techniques and
synthetic chemistry allow high purity pectic domains to be
generated for use in animal studies and in in vitro cell
cultures. Progress is being made and most evidence
indicates that the complex side chains of pectin are
important with regard to anti-cancer activities and other
bioactive properties (Yamada, Kiyohara & Matsumoto,
2003). So far pectin producers have been hesitant about
promoting the potential neutraceutical effects of their
products. However, if convincing evidence of the health
activities of defined pectic domains is demonstrated then
this may change.
with the aim for producing a pectin with the greatest
stabilisation capacity at the lowest concentration. Lime
pectin with long contiguous stretches of un-esterfied GalA
residues was significantly more effective at preventing
sediment than a range of other pectins (Fig. 5).
Pectinolytic enzymes
The removal of pectin is just as important for some food
applications as is the addition of pectin for others. The most
important classes of industrial pectinolytic enzymes are
PMEs, endo- and exo-PGs and pectin lyases. These
enzymes are used to improve juice yield when pressing
and are also employed to regulate the degree of haze and
cloudiness. Pectinases are also used during oil extraction
and in coffee and tea production where they are used to
remove the mucilage coat from coffee beans and to
accelerate tea fermentation (Kashyap, Vohra, Chopra &
Tewari, 2001). Many industrial pectinases are from
microbial sources and there have been major recent
advances in our understanding of their structures and
activities. For example, crystal structures have been
obtained for plant and microbial PMEs and fungal PG
(van Santen et al., 1999. Jenkins, Mayans, Smith, Worboys
& Pickersgill, 2001. Johansson, El-Ahmad, Friemann,
Jornvall, Markovic & Eklund, 2002). Site-directed mutagenesis has provided detailed insights into the molecular
basis of their activity. The industrial importance of PMEs
with novel modes of action is increasingly recognised.
Increased knowledge of such activities can lead to more
rational use and the production of pectins with tailor made
functionalities (Savary et al., 2003). This is illustrated by the
recent development of specialised pectin for acidified milk
drink stabilization (Fig. 5). Pectins prevent sedimentation of
milk proteins by the electrostatic binding of HG to casein.
The details of this mechanism are not fully understood, but
it is known that DE and methyl-ester pattern are important
parameters. A variety of pectins that had been digested with
PMEs from plant, bacterial and fungal sources were tested
Acknowledgements
Much of the work described here was performed during
two EU Framework programmes (FP4, ERBIO4CT960685
and FP5; QLK3-1999/00089) and we thank all of the
participants in these consortia. Additionally we thank Tove
Christensen, Hans Christian Buchholt, Hanne Thorsø and
Lars Norregaard for contributions to figures.
Conclusion
Food consumers expect that food should be convenient to
prepare, tasty, safe, healthy and should have a good shelf
life. Moreover, more and more consumers leave many
aspects of the preparation of daily meals to the food
industry. This creates an increasing demand for functional
ingredients with superior properties in the production of
foods—and ‘designer’ pectins are expected to play an
important role in this future. Pectin producers now have the
knowledge and technology to manipulate pectin at all stages
of the production process and in the forthcoming years it is
likely that pectin with new and improved functionalities will
be produced. However, it will be important that these
advances are carefully managed, and that pectin maintains
its deserved reputation as a ‘natural’ product.
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