Gums and stabilisers for the food industry 14 (special publications) royal society of chemistry (2008)

Edited by Petcf A vviỉlurm and Qyn 0 Ptìằiltps
Gums and Stabilisers for the
Food ỉndustry 14
RSCPublishing
Gums and Stabilisers for the Food Industry 14
Gums and Stabilisers for the Food
Industry 14
Edited by Peter A. Williams
Centre for Water Soluble Polymers, North East Wales Institute, Wrexham, UK
Glyn o. Phillips
Phillips Hydrocolloicỉs Research Ltd, London, UK
The proceedings of the 14th Gums and Stabilisers for the Food Industry Coníerence held on 18-
22 June 2007 at NEWI, Wrexham, UK.
Special Publication No. 316 ISBN: 978-0-85404-461-0
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Preíace
The preparation of this Preíace to the Proceedings of the 14
th
Gums and Stabilisers for
the Food Industry Coníerence is this time a poignant undertaking. This Conference was special
for me since I was awarded the Food Hydrocolloids Trust Medal aíter a session when many of
my colleagues and my son Aled gave presentations. These were both personal and recalled
work of by-gone days. So it is only íĩtting that I here thank all those who were involved in
organising this session and for the Trustees in giving me this very special honour.
The high Standard of the presentations is evident once again in this volume. There is
no better way to leam about new developments in food hydrocolloids research than to brows in
these volumes as they appear every two years. As I travel from country to country and lab to lab
it is gratitying to see these volumes on the shelves, and to note the constant references to the
papers published. This volume will again take the subject forward.
The íĩrst section deals with Novel Hydrocolloid Functionality, which is a target for
most hydrocolloid users. With the number of new food hydrocolloids not likely to increase in
the Corning years because of the standstill in industrial research in this tield, more must be
squeezed out of the presently available materials. It is a fascinating and innovative section.
These subject areas demonstrate the diversity of the presentations:
• polymers versus particles
• visualisation of hydration and swelling
• swelling of calcium pectin gel beads
• processing-structure-property relationships
• rennet-induced gelation of milk in the presence of pectin
• períormance of resistant starch type 3
• bulk deformation behaviour of gellan gum on cross-linking with mixed cations.
• hydration study of soy protein in the 'dry State'
• adhesive of gelatinised starch granule
• extrusion Processing of xanthan
• high intensity ultrasonication of pectin

• gel temperature of pectin and pectin-calcium-gels
• transitions in egg protein dispersions
The ingenuity demonstrated in many of the papers is truly admirable as is the global nature of
the presentations.
The present coníerence called for papers on Sensory-Texture Relationships. The
contributions were varied and dealt with the eíĩect of texture on ílavour release, effect of
microstructure on ílavour diffusion and release and the sensory and rheology of ílaxsecd gum-
fortified dairy beverages.
Hydrocolloid Emulsifiers remain a very interesting and well studied subject. The
Leeds group led by Eric Dickinson continues to unravel the complex processes in the íbrmation
and breakdown of emulsions. Gelatine, hydroxypropyl cellulose, mannans and xylans, are now
making their mark in the food emulsiíĩcation area. The potential of sugar
beet pectin continues to interest but despite the research efforts the practical commercial
application is still minimal.
A major target of this Conference was Hydrocolloids and Health. The papers did not
disappoint. We are constantly being urged to increase dietary íĩbre, remove fat, include
antioxidants, reduce calories etc. The papers cover each of these areas and show that
hydrocolloids can be in the front line in the battle against obesity.
The íĩnal three sections deal with:
• Interactions in mixed hydrocolloid Systems
• Innovative applications
• Developments in characterisatỉon (of hydrocolloids)
These papers form the backbone of the subject and all workers in the íield will need to scrutinize
these papers for new materials, new phenomena and new techniques. It is gratifying to note that
hydrocolloids too can successfully enter the new nano structure era.
I am happy, thereíòre, once again to commend the volume to the growing body of
researchers in food hydrocolloids. In China recently I found a remarkable growth in interest in
this subject and the conference I attended attracted more than 600 participants who traveled
from all parts of China. It is fítting, therefore, that the Food Hydrocolloids Trustees have
approved that the 10

th
International Hydrocolloids Conference should be held in Shanghai under
the Chairmanship of Protcssor Hongbin Zhang of Jia Tong University where the polysaccharide
íĩeld is well and ílourishing. Please note the date now - June 2010, following the 9
th
Conĩerence
in Singapore in 2008.
Finally, may I thank my expert Organising Committee for their constant efforts to
identify subjects of current interest and point to the specialist lead speakers who can deliver
these subịects effectively?
Glyn o. Phillips
Chairman, Gums and Stabilisers Conterence Organising Committee
6 Preface
Contents
The Food Hydrocolloids Trust Medal Lecture
Giving nature a helping hand 3
G. o. Phillips, NEWI, ÌVrexham, UK
1. Novel Hydrocolỉoid Functionality
Mixing hydrocolloids and water: polymers versus particles 29
J.R. Mitchell, A.L. Ferry, M. Desse, S.E. Hiỉl, J. Hort, L. Marcinni and B. Wolf, University of
Nottingham and Queens Medical Centre, Nottingham, UK
Detailed microscopic visualisation of hydration and swelling in a rapidly 40 hydrating particle
bed containing a cellulose ether
S. R. Pygall, p. Timmins and C.D. Melia, University of Nottingham and Bristol
Myers Squibb, Moreton, UK
Swelling behaviour of calcium pectin gel beads 47
M. Iijima, M. Takahashi, T. Hatakeyama and H. Hatakeyama, Nagasaki University, Shinshu
University, Lignocell Research and Fukui University, Japan
Processing-Structure-Property relationships in biopolymer gel particles 53
р. Burey, B. Bhandari, T. Howes and M. Gidley, The University of Queensland, Australia

Diffusing wave spectroscopy studies of rennet-induced gelation of milk in the 61 presence of
pectin
A. Acero Lopez, M. Corredig, M. Alexander, University of Guelph, Canada
Períòrmance of resistant starch type 3 in non pre-fried battered food 68
T. Sanz, A. Salvador, S.M. Fiszman, ITIA, Spaìn
Textural and colour changes during storage and sensory shelf life of muffms 73 containing
resistant starch
R. Baixauli, A. Savador and S.M. Fiszman, CSIC, Valencia, Spain
Dramatic changes in bulk deíbrmation behaviour of gellan gum on cross-linking 79 with mixed
cations
J.J. Harris, A.M. Smith, R.M. Shelton, University of Birmingham and Aston Universỉty,
Birmingham, UK
Hydration study of soy protein in the 'dry State' 87
с. Keaỉỉey, M. Rout, I. Appelqvist, K. Strounina, A. Whỉttaker, M. Gidley, E.
Gilbert and p. Lillỷord, Australian Nuclear Science and Technology Organisation,
Food Science Australia and The Universitv of Queensland, Australia
Nuno M. Sereno, Sandra E. Hill, John R. Mitchell, University of Nottingham, UK
Effect of high intensity ultrasonication on the rheological characteristics of 123 selected
hydrocolloid Solutions
B. K. Tiawri, K. Mnthukumarappan, c.p. 0’Donnell and P.J. Cullen, ưniversity Coỉlege
Dublin, Ireland, South Dakota State ưniversity, USA and Dublin Institute of
Technology, Ireland
Pectin is an alkali scavenger: potential usage in skincare 129
Jens Trudso, CP Kelco, Denmark
Demethylation of a model homogalacturonan with a citrus salt-independent pectin 141
methylesterase: effect of pH on block size and number, enzyme mode of action and resulting
functionality
R.G. Cameron, G.A. Luzio, K. Goodner, M.A.K. Williams, USDA, ARS, Citrus and Subtropical
Products Laboratory and Massey University, New Zealand
Gelling temperature determination in pectin-based Systems 153

L. Boettger, S.H. Christensen and H. Stapelfeldt, CP Kelco, Denmark
Characterization of pectin-calcium-gels: Iníluence of pectin methoxylation 164 properties
I. Fraeye, E. Vandevenne, T. Duvetter, A. van Loey and M. Hendrickx, Katholieke
Universiteit, Leuven, Belgium
G. D. Goff, A.E. Muller, F. Capel, C.J. Findlay and w.s. Cui, University of Guelph,
Compusense Inc. Agriculture and Agri-Food Canada, Canada and Universitat
Hohenheim, Germany
2. Hydrocolloid Emulsiỉỉers
Controlling emulsion stability: microstructural and microrheological origins of 211
Aocculating Systems
B.s. Murray, Universừy of Leeds, ƯK
Emulsifícation and stabilisation with protein-polysaccharide complexes 221 Eric Dickinson,
University of Leeds, UK
Dynamic rheological properties of gelatine films at the air/water interíace 233
s. Domenek, R. Abdeỉli, s. Mezdour, s. Guegj, N. Brambati, c. Ridoux and c.
Michon, AgroParisTech-INRA-CNAM and Rousselot, France
Kinetics of adsorption of gelatine at the air/water interface: Effect of concentration 239 and
ionic strength
s. Domenek, E. Petit, A.s. Delbes, s. Mezdour, s. Guedj, N. Brambati, c. Ridoux and c.
Michon, ENSIA, Massy and Rousseỉot, France
Chee Kiong Siew and P.A. Williams, NEWI, Wrexham, UK
Effect of thermal treatments and pH modiíication on the rheological properties of 264 o/w
emulsions stabilised by food proteins
c. Bengoechea, A. Romero, F. Cordobés and A. Guerrero, Universidad de Seviỉỉa,
Spain
8 Contents
Stability of emulsions containing sodium caseinate and anionic polysaccharides 272
L. Jonrdain, M.E. Leser, c. Schmitt, E. Dickinson, University of Leeds, UK and
Nestlé, Switzerland
Characterisation of Gum Ghatti and comparison with Gum Arabic 280

s. Al-Assaf, V. Amar, G.o. Phillips, Phillips Hvdrocolloids Research Centre,
NEWI, UK and The Gums and Colloids Group, India
3. Hydrocolloids and health
The role of hydrocolloids in the íòrmulation of healthy foods 293
H. T. Norton, p.w. Cox andF. Spyropoulos, University of Birmingham, UK
Elydrocolloids in health 306
A. Phillips and s. Riley, University ofWales Hospital, Cardiff, UK
The effect of hydrocolloids on satiety, and weight loss: areview 313
T. Paeschke and W.R. Aỉmutis, Cargill, Inc., USA
Utilization of sodium caseinate nanoparticles as molecular nanocontainers for 326 delivery of
bioactive lipids to food Systems: Relationship to the retention and controlled release of
phospholipids in the simulated digestion conditions
M.G. Semenova, L.E. Belyakova, Y.N. Polikarpov, A.s. Antipova, and M.s. Anokhina, Russian
Academv of Sciences, Russia
Real-time CSLM observations on alpha-amylase digestion of starch in isolated 334 form and
within cellular integrity
s. Oyman, J.G.C. Blonk, H.T.W.M. van der Hijden, H.p.p. Peters and S.E. Hill, University
o/Nottingham, ƯK and Unilever R&D, The Netherlands
Biopolymer structures for novel gastro-intestinal functionality: in vitro 341
characterisation and behaviour in vivo using MRI
р. Rayment, s. Pregent, C.L. Eỉoad, E. Ciampi and M.F. Butler, Unilever R&D Colworth and
University of Nottingham
Calcium alginate as a gastro-activated dietary ííbre 349
o. Gẵserod, H. Haraldsen and G. Lynch, EMC Biopolymer Nonvay and Belgium
Pectin - health beneíits as a dietary ííbre and beyond 358
o. Hasseỉwander, Danisco Sweetners Ltd, UK
Extraction, characterisation and anti-inílammatory bioactivity of polysaccharides 367 from
boat-fruited sterculia seeds
Y. Wu, s. w. Cui, J. Tang, Q. Wang and X. Gu, Shanghai Jiao Tong University,
China and Agriculture and Agri-Food Canada, Guelph, Canada

Structuring of low calorie food with fruit íìbres 379
Jurgen Fischer, Herbaýood Ingredients, Germany
Rheological behaviour of carboxymethyl cellulose dairy desserts with different fat 386 content
s. Bayarri and E. Costeỉl, CSIC, Valencia, Spain
The role of hydrocolloids in the management of dysphagia. 392
G. Sworn, E. Kerclavid, J. Fayos, Danisco SAS, Erance
Contents 9
Antioxidant activity of soy protein hydrolysate and peptides 402
с. Kasase, A. Ganeshalingam and N. Howelỉ, University of Surrey, UK
4. Interactions in mixed hydrocolloid Systems
Modelling of the rheological behaviour of the temary Systems of tragacanth, guar 409
gums and methylcellulose as a íunction of concentration and temperature
C. A. Silva, F. Chenlo, R. Moreira and G. Pereira, Universidade de Santiago,
Spain
Structural properties and phase model interpretation of the tertiary System 419 comprising
gelatin, agarose and a lipid phase
p. Shrinivas, T. Tongdang and s. Kasapis, National University of Singapore, Singapore and
Prince Songkla University, Thaỉland
Complex coacervation between P-lactoglobulin and K-caưageenan 427
I. Dovle, J.s. Mounsey and B.T. 0’Kennedv, Moorepark Food Research Centre,
Ireland
Viscoelasticity of starch-milk Systems with inulin added. Iníluence of inulin Chain 435 length
and concentration
L. Gonzalez-Tomas, J. Coll-Marques and E. Costell, CSIC, Vaỉencia, Spain
Interaction of different gelling carrageenans with milk proteins 440
J. de Vries, D. Arltoft and F. Madsen, Danisco A/S and University of Copenhagen, Denmark
AFM and DSC Studies on Gelation of Methylcellulose Mixed with Sodium 446 Cellulose
Sulfate
T. Hatakeyama, M. Dolýima, T. Onishi and H. Hatakeyama, Lignocel Research and
Fukui University, Japan

The effect of ĩiller orientation on the mechanical properties of gelatin-MCC 454 composites
Lee Wah Koh, s. Kasapis and D. Teck Lip Tam, National University of Singapore, Singapore
Characterisation of rheological properties of mixtures of whey protein isolate and 461 inulin
J.T. Tohin, S.M. Fitzsimons, E.R. Morris and M.A. Fenelon,Teagasc, Food Research Center,
University College, Cork, Ireland
Effect of shearing on the phase diagram and rheological behaviour of an aqueous 469 whey
protein isolate-K-carrageenan mixtures
s. Gaaỉoul, s. Turgeon, M. Corredig, Université Laval, Saỉnte-Foy and University of
Gueỉph, Canada
Pectin-protein complexes-new roles for pectin extracts 477
V.J. Morris, A.p. Gunning, A.R. Kirby and A.J. MacDougaỉỉ, Institute of Food Research
5. Innovative Applications
Microalgae biomass as a novel íunctional ingredient in mixed gel Systems 487
A.p. Batista L. Gouveia, M.c. Nunes, J.M. Franco, A. Raymundo, ISEIT de Almada, INETI-
DER-Unidade Biomassa, Portugal and Universidad de Huelva,
Spain
Cellulose gum as protective colloid in the stabilization of acidified protein drinks 495
10 Contents
M. van cler Wielen, w. van de Heịịning, Y. Brouwer, CP Kelco, The Netherlands
Protein Stabilization and Particle Suspension in Aciditĩeđ Protein Drinks Using a 503 Dual-
function Hydrocolloid System.
C.R. Yuan, M. Kazmierski-Steele and p. Jackson, CP Kelco, USA
Nanostructures and nanoíòods 510
V.J. Morris, Institute of Food Research, Nonvich, UK
High-pressure-induced yuzu maimalade 518
H. Kuwada, Y. Jibu, K. Yasukawa, s. Makio, A. Teramoto and M. Fuchigami, Okayama
Pre/ectnral University and Kanto Gaknin University, Japan
6. Developments in Characterisation
Molecular structures of gellan gum imaged with atomic force microscopy (AFM) 527 in
relation to the rheological behavior in an aqueous Systems. Gellan gum with various acyl

contents in the presence or absence of potassium T. Funami, s. Noda, s. Ishihara, M.
Nakauma, R. Takahashi, s. Al-assaf, K. Nishinari, and G.o. Phillips, San-Ei Gen F.F.I. Inc.,
Gunma University, Japan,
Phillips Hydrocolloid Research Centre, UK
Rapid determination of alginate monomer composition using Raman spectroscopy 543 and
chemometrics
T. Salomonsen, H.M. Jensen, D. Stenbaek and S.B. Engelsen, Danisco and University of
Copenhagen, Denmark
Physicochemical properties of starch isolated from sago palm (metroxylon sagu) 552 at
different palm heights
B.A. Fasihuddin and P.A. Williams, Universiti Malaysia Sarawak and North East Wales
Institute, UK
A cutting edge technology in the rheological studies of thermal Processing of 558 polymers:
measuring response to high temperature treatment using a high pressure cell
M.s. Kok, Abant Izzet Baysaỉ University, Turkey
Contents 11
Acknovvledgements
The Food Hydrocolloids Trust are indebted to the coníerence organising
committee;
Dr p. Boulenguer, Cargill France SAS
Dr s. Davies, ICI p!c, UK
Proíessor E. Dickinson, University of Leeds
Proíessor E. A. Foegeding, North Carolina State University, USA
Dr T. J. Foster, University of Nottingham, UK
Dr I. Hodgson (ViceChairman), lan Hodgson Associates
Proíessor D. Hovvling, David Howling Associates
Mr H. Hughes (Secretaríat), North East VVales Institute
Dr A. Imeson, FMC Corporation
Mr D.R.J. Lloyd, Cargill
Dr M. Marrs,

Dr R.G. Morley, Delphi Consultant Services Inc., USA Proíesoor J.R. Mitchell,
University of Nottingham Proíessor E. R. Morris, University College Cork, Ireland
Proíessor V.J. Morris, Institute of Food Research, Norvvich Dr J.C.F. Murray
(Treasurer)
Proíessor K. Nishinari, North East Wales Institute
Proíessor G.o.Phillips (Chairman), Phillips Hydrocolloids Research
Dr K. Philp, CyberColloids Ltd, Ireland
Dr c. Rolin, CP Kelco, Denmark
Dr c. Schorsch, Danone, France
Dr c. Speirs, CCFRA
Dr G. Sworn, Danisco, France
Dr M. Taylor Cadbury Schvveppes
Dr A. Tziboula-Clarke, ISP (International Specialty Products)
Proíessor P.A. VVilliams (Sclentiíic Secretary), North East Wales Institute and
also acknovvledge íinancial support from Major sponsors Coca Cola Ltd
Phillips Hydrocolloids Research Ltd San Ei Gen F.F.F. Inc
other sponsors
Cadbury Schweppes
Cargill
CP Kelco
Danisco
Marinalg
Masteríõods
Unilever
The Food Hydrocolloids Trust Medal Lecture
GIVING NATURE A HELPING HAND
Glyn o. Phillips
Glyn o. Phillips Hydrocolloids Research Centre The
North East Wales Institute, Plas Coch, Mold Road,
Wrexham, LL1 1 2AW, Wales

1. INTRODUCTION
There is a considerable appeal for the general public in the concept of “natural” foods.
The food producer, therefore, in the cuưent health conscious climate makes every effort to
equate “natural” with fitness and good living to promote a “green” image without those
nasty Chemicals. Into this category come the indigestible plant polysaccharides, which
were included by Trowell (1) in the definition of dietary fibre. Previously the term had
been used to describe the remnants of plant components that are resistant to hydrolysis by
human alimentary enzymes (2-4). The impending Codex definition of dietary íibre (5)
refers to edible carbohydrate polymers naturally occurring in the food as consumed, and
carbohydrate polymers, which have been obtained from food raw material by physical,
emymatic or Chemical means. The expectation is that these natural polymers would need
to lead to a positive physiological effect, such as: decreased intestinal transit time and
increase stools, bulk fermentable by colonic microAora, reduced blood total and/or LDL
cholesterol levels or reduced post-prandial blood glucose and /or insulin levels. By
association, thereíore, food producers can imply that these natural polymers have healthy
effects when eaten regularly.
I do not wish to cast any doubt about the beneíicial effects of non-starch
polysaccharides and indeed there is ample evidence of their effectiveness in promoting a
healthy life style (6). These have undoubted ađvantages but there are problems to integrate
them into industrial production, which demands constant quality and performance Natural
polymers are never uniform or simple. Their functionality depends on more than one
structural íeature. Extraction processes alter the macro- and micro-structures and
períormance. Their most common íeature is their variability which poses a big problem for
both the producer and User of natural polysaccharides.
This paper draws attention to this variability in three natural polysaccharide Systems:
gum arabic, sugar beet pectin and gum Ghatti. The problem we have tried to solve is how
can we remove this natural variability and secondly how can we enhance
their períormance using methods which would not involve the introduction of new
Chemical groups and so be acceptable to the food industry. In other words can we
circumvent Nature and find ways of producing uniform/constant Products and if possible

with better speciĩic íunctionalities ?
2. GUM ARABIC ( GUM ACACIA)
The cuưent WHO/JECFA Speciíication (1998), which is intemationally accepted and has
also been approved by Codex Alimentarius (INS No. 414) is: Gum arabic is a dried exudate
obtainedỷrom the stems and branches of Acacia Senegal (L.) Wiỉldenow or Acacia seyal (fam.
Leguminosae) (7). For comparison it is noteworthy that the European Speciíication (E 414) is
slightly broader (2003): Acacia gum is a dried exudation obtained from the stems and branches
oỷnatural strains of Acacia Senegal (L) Willdenow or closely related species o/Acacỉa (ỷamily
Leguminosae)(8).
This paper deals with the gum arabic ( A. Senegal (L.) Willd. var. Senegal ). This exudate
gum is a complex polysaccharide consisting of D-galactopyranose (~44 %), L- arabino-
pyranose and íuranose (~25 %), L- rhamnopyranose (14 %), D-glucuropyranosyl uronic acid
(15.5 %) and 4-O-methyl-D-glucuropyranosyl uronic acid (1.5 %). It also contains a small
amount (~2 %) of protein as an integral part of the structure. The carbohydrate structure
consists of a core of P-(l,3)-linked galactose units with extensive branching at the C6 position.
The branches consist of D-galactose and L-arabinose and terminate with L-rhamnose and D-
glucuronic acid (9). Randall et al. (10,11) íractioned A. senegal by hydrophobic affinity
chromatography and showed that it consists of three components namely arabinogalactan
(íraction 1, AG); arabinogalactan protein (ữaction 2, AGP) and a glycoprotein (íraction 3, GP).
Each ữaction contains a range of different molecular weight components which are responsible
for the polydispersity of the gum The AG ữaction contains 88 % of the total gum with small
amounts of protein 0.35 % which represents 20 % of the total protein content, while the AGP
íraction comprises 10 % of the total gum with 12 % protein which is 49.5 % of the total protein
content. Finally the GP íraction contains 1.24 % of the total gum with 50 % protein, which
represents 27 % of the total protein in the whole gum (10.11).
2.1 Natural variability
There is now clear evidence of the great variability within commercial gum arabic
supplied to the market (12). 67 samples of A. Senegal var. Senegal exudate gum, supplied by
primary supplier, producer and User companies were analysed using gel permeation
chromatography (GPC) coupled to a multi-angle laser light scattering detector, a reíractive

index detector and a uv detector operated at 214 nm. A set of 5 samples were íully
authenticated A. Senegal var. Senegal and used to provide norms against which the other gum
samples could be assessed. A Standard unprocessed A. Senegal var. Senegal (hashab) from a 15
years old mature tree was used for comparison. A íeature of the results is the extensive variation
betvveen individual samples, all of which were presented to the market as “gum arabic”. Of the
samples, 15 were outside the selected norms. Table 1 shows the variation found in 13 samples
provided by one company, with each one being marketed as an identical gum arabic product.
There is more than a two-fold variation in weight average molecular weight (Mw) and wide
differences in molecular parameters and amount present of the íractions, including the
arabinogalactan protein (AGP) component. This is the component vvhich is responsible for the
15 Gums and Stabilisers for the Food Industry 14
emulsion capability of gum arabic, so it was inevitable that there was also a wide variation in
the capability of the different samples to íunction in beverage emulsions, for example(12).
2.2 Removing natural variability and conversion of a poor into a good emulsifying gum
Table 2 shows the molecular parameters of two samples of gum arabic, one (labeled CT-
3892) with Mw 8.34 and the other (labeled FR-2635) 4.24 X 10
5
. The former gum was shown to
be an excellent emulsifier whereas the latter was an extremely poor emulsiíier, in accordance
with the different amounts of AGP present in each - 14.4 and 9.6% respectively (13).
We have demonstrated (14,15) that using a newly developed process it is possible to treat the
poor emulsiíier and produce a new product with the molecular parameters comparable with
those of the good emulsiíier. This is the product labeled MI in Tabỉe 2 which has M
w
9.46xl0
5

and AGP content 17%.
Table 1. Molecular weight parameters of guin arabic samples from One company .
File name

M
w
( processed as
One peak
M
W
/MN
%
mass
Rg
nm
M
w
t processed as
two peaks
M
W
/M
N
%
mass
Rg
nm
C3-1
5.83 xio
5
±0.13
1.85
101
26.2

2.01 X 10
b
± 0.05
1.42
15.8
33.6
3.19 X 10
5
± 0.05
1.16
85.6
16.0
C3-2 7.32 xl0
5
± 0.29 2.19 102 30.4 3.11 X 10° ±0.05 1.74
13.3
8
36.72
3.73 X 10
5
± 0.03 1.25 8.4
0.0
C3-3 6.17 X 10
5
± 0.10 1.71 100 20.9 2.09 X 10° ±0.13 1.29 12.7 26.8
3.98 X 10
5
± 0.05 1.23 87.3 15.0
C3-4 3.37 xl0
3

± 0.09 1.82 105 21.7 2.32 X 10
6
± 0.13 1.36 4.2 33.11
2.52 X 10
5
± 0.05 1.41
101
5.1
C3-5 6.68 X 10^ 0.14 2.00 108 28.5 2.44 X 10
b
± 0.07 1.48 15.4 34.9
3.71 X 10
5
± 0.05
1.26
92.6 20.4
C3-5 7.56 X 10
3
± 0.23 2.33 107 33.3 3.56 X 10
b
± 0.16 1 91 12.7 40.22
3.70 X 10
5
± 0.04 1.27 93.5
1.0
C3-6 6.19 Xl0
5
± 0.24 1.62 109 29.7 1.87 X 10
b
± 0.09 1.35 18.6 34.3

3.78 X 10
5
± 0.11 1.14 96.6 24.6
C3-7 6.24 X 10
5
± 0.38 1.59 100 34.5 1.87 X 10
b
± 0.12 1.36 16.6 37.8
3.88 X 10
5
± 0.22
1.11
85.5 31.0
C3-8 5.58 X 10
3
± 0.25 1.58 106 32.5 1.79 X 10
b
± 0.08 1.34 15.1 36.8
3 55 X 10
5
± 0.16
1.11
91.7 27.9
C3-9
6.36 xl0
5
± 0.25
1.53
101
31.4

7
1.69 xl0
b
± 0.07
1.30
16.9
34.8
3.90 X 10
5
± 0.17
1.11
85 27.4
C3-10 1.15 X 10
b
± 0.09 3.96 110 44.7 5.90 X 10
b
± 0.56 2.96 16.9 50.12
3.95 X 10
5
± 0.16 1.54 105 7.9
C3-11 1.20 X 10
b
± 0.05 4.39 102 44.6 5.94 X 10
b
± 0.25 2.92 16.6 50.02
3.84 X 10
5
± 0.17
1.61
97.6 5.3

C3-12 6.06 X 10'±0.48 2.11 101 35.0 2.68 X 10
b
± 0.13 1.55 12.2 42.5
3.47 X 10
5
± 0.16 1.33 88.3 25.8
C3-13 7.19 X 10
5
± 0.60 3.00 103 39.3 4.63 X 10
b
± 0.50 2.51 10.0 47.3
3.47 X 10
5
± 0.18 1.57 93.2 24.5
16 Gums and Stabilisers for the Food Industry 14
The process can be continued (M1-M4) such that a product with a Mw of ca. 2 xio
6
and
AGP content of more than 20%. Using Standard emulsion formulations which have been
described (16).
Emulsiíication effectiveness was evaluated based on the initial particle size of the
emulsions which were then subjected to an acceleration testing (7 days storage at 60°C).
Particle size diameter of emulsion aíter the acceleration test was measured using a particle size
distribution analyzer. Emulsiíication stability was evaluated by the change in particle size of
emulsion after acceleration test. The change in particle size after the acceleration test (7 days
storage at 60 °C) was taken as a parameter to designate the category of the gum sample.
Therefore, the gum samples which showed a change of 0.1 pm or less were given category 1
(good emulsiíìer). A change >0.1 pm - 1.0 (nn are classed category 2. The less stable emulsions
which showed a change >1.0 pm were allocated category 3 (poor emulsiíier).
The process is shown to have converted a poor Class 3 emulsiíier into an excellent Class

1 emulsiíier (Table 3).
Table 2 Molecular vveight parameters of poor emulsifier (FR-2635) sample and after maturing
to obtain increasing proportions of high molecular weight polysaccharide-protein complex.
Sample name Processing
Molecular weight
(M
w
g/mol)
Recovery
(%)
Polydispersity
(M
w
/Mn)
Rg
(nm)
CT-3892 Whole gum 8.34±0.26xl0
5
106 2.23 25
First peak (AGP) 3.06±0.10xl0
6
(14.4) 1.29 34
Second peak (AG+GP) 4.73±0.19xl0
5
(85.6) 1.43 26
FR-2635 Whole gum 4.24±0.20xl0
5
110.6 1.85 33
(Control) First peak (AGP) 1.55±0.07xl0
6

(9.6) 1.12 41
Second peak (AG+GP) 3.03±0.14xl0
5
(90.4) 1.47 26
PR-2635/M1 Whole gum 9.46±0.50xl0
5
117.0 2.90 55
First peak (AGP) 3.57±0.17xl0
6
(17.2) 1.37 65
Second peak (AG+GP) 4.00±0.25xl0
5
(82.8) 1.45 27
FR-2635/M2 Whole gum 1.73±0.09xl0
6
102.5 3.85 73
First peak (AGP) 6.06±0.31xl0
6
(22.1)
1.61 81
Second peak (AG+GP) 4.99±0.23xl0
5
(77.9) 1.39 35
FR-2635/M3 Whole gum 1.95±0.09xl0
6
77.4 3.78 62
First peak (AGP) 6.70±0.28xl0
6
(22.5) 1.40 68
Second peak (AG+GP) 5.72+0.30xl0

5
(77.5) 1.39 32
FR-2635/M4 Whole gum 1.45±0.06xl0
6
71.8 3.72 59
First peak (AGP) 4.69±0.18xl0
6
(24.0) 1.43 65
Second peak (AG+GP) 4.17±0.24xl0
5
(76.0) 1.37 32
17 Gums and Stabilisers for the Food Industry 14
2.3 The maturation process
The process is carried out in a dry stainless Steel Container or on a suitable surface,
open to air or in a non-oxidizing environment (an atmosphere of nitrogen). The treatment
involves maturation under strictly controlled conditions of temperature and humidity of the dry
gum (13,14). The method is essentially one that is used in Standard food Processing and
promotes the íurther maturation of gum arabic in a way, which emulates and extends that which
occurs naturally.
As the tree grows in the Sudan the molecular weight of the exuded gum arabic increases
from 250,000 (at 5 years) to a maximum of 450,000 (after 15 years) and the amount of protein
and of the high molecular weight protein íraction also increases with the age of the tree (17).
This build-up in the tree effectively unites small molecular weight fractions, which contain a
small amount of protein into the larger units, of which the ultimate is the arabinoglactan protein
with molecular weight of some 2.5 X 10
6
. The carbohydrate and amino acid composition of
these smaller sub-units are identical (11,18). Thus, the biological process involves initially the
íòrmation of the sub-units and then these are joined into larger units as the tree grows.
Moreover this change of composition continues after the gum is initially harvested.

Proíessors J. c. Fenyo and J. Vassal studied ÍVeshly collected gums (so-called green- gum)
from A. Senegal and observed the change in the properties on maturing (19). After storage over
a year the speciíic rotation, nitrogen (hence protein) and intrinsic viscosity changed
significantly, indicative of a continuing change in the molecular aggregation process.
The process which has now been developed to produce a new series of “Supergum” arabic
accelerates and enhances this same natural aggregation process, under strictly controlled
conditions, which were worked out first at laboratory, then pilot scale and íinally at plant level.
The smaller arabinogalactan units containing some protein, join to form larger molecular
weight arabinogalactan protein (AGP) aggregates. By monitoring the molecular architecture of
the gum at all stages, speciíic new Products have been produced and characterised. In all
aspects this specially matured gum is chemically and molecularly identical to the base gum, but
because of the diíTerence in distribution of smaller units into larger aggregates, the physical ad
íunctional períormance is greatly enhanced. The details can be found in a series of publications
(16, 20-23).
“SuperGum” arabic produced by accelerated maturation process is chemically and
immunologically identical to gum arabic as collected from the tree.
18 Gums and Stabilisers for the Food Industry 14
• Contains exactly the same sugar moieties and in the same proportions as control gum,
which has not been subjected to the accelerated maturation process
• Contains exactly the same amino acids and in the same proportions as control gum,
which has not been subjected to the accelerated maturation process
• Nature of structural bonding is identical with control gum, which has not been
subjected to the accelerated maturation process
• Immunologically identical to gum, which has not been subjected to the accelerated
maturation process
• Only the degree of the organisation of the components has been changed by the
process, with the not so useíul low molecular weight protein aggregating to form the
essential high molecular weight protein
• No new Chemical groups introduced as a result of the accelerated maturation process
Table 4. Molecular weight of control and matured gum arabic by GPC-MALLS analysis

Sample name Processing
Molecular weight
(Mw, g/mol)
% Mass
uv peak area
(%)
Rg
(nm)
Control gum arabic one peak 6.22 X 10
5
28.5
FR-2876 two peaks (1, AGP) 2.54 X 10
6
10.6 28.8
41.1
two peaks (2, AG+GP) 3.96 X 10
5
89.4 71.2
-
Matured gum arabic
A
One peak 1.23 X 10
6
59.0
ER-2877 two peaks (1, AGP) 6 58 X 10
6
13.2 42.9 68.7
two peaks (2, AG+GP) 4.13 X 10
5
86.8

57.1
-
Matured gum arabic
B
one peak 1.66 X 10
6
64.2
ER-2788 two peaks (1, AGP) 8.56 X 10
6
15.3 52.6 709
two peaks (2, AG+GP) 4.16 X 10
5
84.7 47.4
-
Matured gum arabic
c
one peak 2.54 X 10
6
85.1
FR-2789 two peaks (1, AGP) 1.16 X 10
7
18.6 53.1 89.8
two peaks (2, AG+GP) 4 50 X 10
5
81.4 46.9
-
Matured gum arabic
D
one peak 1.08 X 10
ổ

63.6
Supergum EM1 two peaks (1, AGP) 5.98 X 10
6
12.3 35.3 74.5
two peaks (2, AG+GP) 3.90 X 10
5
87.7 64.7
-
Matured gum arabic
E
One peak 1.77 X 10
6
68.4
Supergum EM2 two peaks (1, AGP) 7.84 X 10
6
18.2 54.0 75.5
two peaks (2, AG+GP) 4.16 X 10
5
81.8
46.0 -
Table 4 shows the change in molecular parameters for a series of gums ER-2876 to FR- 2879
and shows also the two Products which have been selected for commercial release:
Supergum EM1(M
W
1.08 X 10
6
) and EM2(1.77 X 10
6
). EM1 is produced to provide a good
emulsifying gum of conventional qualities and EM2 a gum with enhanced emulsifying

qualities which can operate in beverage emulsions at one third to one quarter of the
concentration normally used for commercial gum arabic (20%), depending on the nature of
the emulsion. The molecular aggregation processes can be illustrated at
19 Gums and Stabilisers for the Food Industry 14
which shows that aggregation of the high molecular weight protein is the effective
chan
Figure 1. GPC overlay chromatogram of gum arabic showing the light scattering (LS)
reĩractive index (RI) and uv at 214nm. The data was normalized as ũỷected mass of 0.4
to display on the same Y-axis
Elution Volume
Elution Volums
Elutỉon
Elution Voiuma
Elut ion
Elution Volume
2.5 Enhanced emulsification períormance in real Systems
In íorming stable emulsions it is the hydrophobic moiety of the arabinogalactan
protein (AGP) of the gum arabic which bridges the hydrophilic barrier to coat the oil
droplet, with the driving force being directed by the entropic energy of the hydrophilic
carbohydrate groups residing in the water layer (Figure 3). In the matured Supergum
Products the protein is aggregated and can offer 7 or 8 greater suríace dimensions with
consequent stronger binding forces. Electrostatic and steric stabilizing iactors are
improved by the treatment. This leads to the ability to stabilise smaller droplet sizes and
to provide considerable greater long-term stability for the emulsions. This is illustrated in
Figure 4 for the samples described in Table 4. Figure 5 shows the comparison with
Standard gum arabic in a complex concentrated beverage emulsion and shows that EM2
is more eriective at 4 times less concentration
molecular level using GPC-MALLS (Figure 1) and atomic force microscopy (Figure
The Food Hydrocolloids Trust Medal Lecture 20
Figure 2 . Atomic force image of conventional gum arabỉc and supergum EM2

Diqi tal
Scan rate
IM um ber <jf
sa mp Irnage
Htìig
qc+o.5mni_lug_fcm_d.
Quickgum 8074 (A. Senegal)
NiCI
2
at 0.5mM
Di gita l Inst ru ments Na no Scope
Scan'size 5.000
|.im
Scan rate 1.001
Hz
em2 +0.3 rnn 1 _1 u g_f
Supergum EM2 (A. Senegal)
NiCI
2
at 0.3mM
Figure 3 Schematic representation
of emulsiíication of gum arabic
Figure 4. Stability of emulsions prepared using control and matured
gum arabic. Blue bar: initial VMD; red bar : VMD aíter Accelerated
Temperature Stress Test at 60° using various concentrations of gum
FR-
FR-
FR-
FR-
Superg

Superg
0.0 0.5 1.0 1.5 2.0 2.5 3.0
VMD
I
Figure 5, Acceleration storage test at 60°C: comparison with Standard gum
arabic (SDGA)
(Aíter 7 days)
From the left,
EM2 EM2 SDGA SDGA
5% 10% 10% 20%
At SDGA 10%. oil Aoating.
3. SUGAR BEET
POLYSACCHARIDE
Pectin (INS 440, E440) by regulatory delmition consists mainly of the partial methyl esters
of polygalacturonic acid and their sodium, potassium and ammonium salts. It is obtained by
aqueous extraction of appropriate edible plant material, usually citrous íruits of apples. It uses
permitted under this deíinition are as a gelling agent, thickening agent and stabilizer.
Here we are concemed with sugar beet pectin which has quite distinctive characteristics,
but has not yet found widespread use. Corning from such an abundant raw material to develop a
market specific to this product would be signiíicant. It early hopes of providing an alteraative as
an emulsiíier for gum arabic have not been realized, due mainly to its inability to stabilize
emulsions with sufficient robustness in the hard world of beverage emulsions. Our objective,
thereíore, has been to improve its períormance and find applications which would utilize the
special characteristics of this interesting natural product. The work I shall describe here is a
collaboration betvveen the Glyn o. Phillips Hydrocolloids Research Centre and San-Ei Gen FFT
Inc led by Dr Takahiro Funami.
The íeatures associated with the emulsiíication of sugar beet pectin have been recently
described (24 - 26). Pectin molecules, generally (27) have a backbone of a-(l-
Gravity
Viscosity of

Particle Size Distribution
Gum Arabic
Oil
Emulsion
(mPa- s)
V.M.D.(ụ m)
1.3Ụ mr (%)
EM2 5%
4) -linked d-galacturonic acid with (l-2)-linked 1-rhamnopyranosyl residue in adjacent
or altemate positions. The side chains consist mainly of D-galactose and L-arabinose linked vía
the glycosidic to 04 and/or 03 of the 1-rhamnopyranose. As distinct from pectin from other
sources, sugar beet has a higher proportion of neutral-sugar side chains (rích in hairy regions)
(26) a higher content of acetyl group at 02 and 03 positions within the galacturonic backbone
(28), a higher content of phenolic esters in the side chainsespecially arabinose and galactose
(26, 28 - 30) and a higher content of the proteinaceous materials bound to the side chains
through covalent linkages (26) Pectin from sugar beet does not form gels thermally even in the
presence of high concentration of soluble solids (e.g., sugar) at low pH (< 3^1) conditions.
Since the high molecular weight protein component is the active entity in controlling the
emulsiílcation of gum arabic it was important to establish to what extent the protein functions
similarly in sugar beet pectin. To answer this question, the properties of sugar beet pectin were
examined beíore and after enzymatic modiíication using multiple acid- proteinases. The
enzymatic treatment decreased the total protein content from
1. 56±0.15% to 0.13±0.02% without a significant change in content of ferulic acid or
most constitutional sugars. The enzyme treatment also decreased the weight-average molecular
weight (M
w
) from 517±28 to 254±20kg/mol and the z-average root-mean- square radius of
gyration from 43.6±0.8 to 35.0±0.6 nm.
Emulsiíying properties beíore and after the enzymatic modiíication were evaluated by
measuring emulsion droplet size and creaming stability of 0/W emulsions (pH 3.0) containing

15 w/w% middle-chain triglyceride and 1.5 w/w% sugar beet pectin as main constituents. The
emulsiíication performance was much poorer after the enzyme treatment. The average diameter
(dĩ 2) of the emulsion droplet increased from 0.56±0.04 to 3.00±0.25 pm for the pre- and post-
enzyme sugar beet pectin respectively. After enzyme treatment also the product gave emulsions
vvhich showed extensive creaming on incubation at 60 °c. This was consistent with the
macroscopic phase separation which occurred only in the presence of the enzyme modiíied
pectin after storage at 20 °c for a day. The enzyme modification also decreased significantly the
amount of pectin íraction that adsorbed on to the suríace of oil droplets from 14.58±2.21% to
1.22±0.03%. The interfacial concentration decreased from 1.42±0.23 to 0.45±0.05 mg/m
2
,
indicating the role of proteinaceous materials in the pectin molecules at the oil-water interíace.
It seems clear, thereíore, that it is the protein hydrophobic part of the sugar beet pectin
which is attracted to the oil droplet to stabilize the emulsions. When the protein is enzymically
partially removed the emulsiíication properties decrease. The proteinaceous moiety íunctions to
increase the surface activity of the polysaccharide and its accessibility to emulsion droplets. The
mechanism of emulsiíication thus has clear similarities with those of gum arabic (24).
In view of the Central role of the protein in the emulsiíication process, it was a natural step
to apply the enhancement process already described for gum arabic to see whether a similar
aggregation could be achieved and whether this also would provide better stability for the sugar
beet pectin (SBP) emulsions.
An indication of the changes which can be produced by the controlled heating process
(13,14) is shown in Table 5. The weight average molecular weight (Mw) can be increased from
484 to 652kg/mol. When the largest molecular aggregate has been produced there is also an
increased in insoluble tractìon due to the íormation of hydrogel at the limit of the solubility of
the SBP, paralleled also by the increased viscosity. When emulsions are produced, using MCT
as the oil phase, and homogenized twice at 50Pa there is a consistent improvement in the
stability of the emulsion and regirae has improved the stability compared with the control SBP
by approximately 6 times.
Atomic force microscopy (AFM) provides a visual image of the effect of the enhancement

process (Figure 6). The chains as a result of the heating process associate to
Figure 6
Many actual Products have been produced to illustrate the excellent properties of the
enhanced sugar beet pectin, which eliminates the weakness shown by the unprocessed SBP.
Figure 7 shows a model drink with 20% orange oil stored after sterilization at 40°c for 1 week.
The control SBP is completely unstable and phase separation is evident whereas the enhanced
product showed no such behaviour.
Dr Takahiro Funami and colleagues have cleverly measured the thickness of the hydration
layer around the suríace of the oil droplet (31) by using a combination of dynamic light
scattering and enzymatic treatment using pectinase (Figure 8). The enzyme treatment decreased
the hydrodynamic radius ( RH ) due to degradation of the carbohydrate moiety that íorms the
hydrated layer. Rh then increases due to the ílocculation of emulsion droplets. From the
decrease in Rh the thickness in the layer surrounding the oil droplet can be estimated, which is
considerably thicker for the enhanced gum compared with the control sample. Figure 9
illustrates the enhancement process and describes how the enhanced sugar beet pectin períorms
in emulsion Systems so effectively (31).
Table 5 Stability of QAV emulsion with enhanced sugar beet pectin
1
SBP
from
íresh
peel
Average particle size
of 0/W emulsion
2
(mm)
Fundamental properties of modiíied sugar beet pectin
Treatments
Initial
Aíter 3days at 60C

M
W
J
(kg/mol)
Total insolubles
4
(%)
Aqueous viscosity ( mPa- s)
5
Control
0.64
1 From íresh peel
2 1.0% pectin, 15% middle-chain tri-glyceride; íinal pH 3.0;
homogenized twice at 50 MPa
3 All samples were homogenized twice at 50 MPa prior to SEC-
MALS analyses.
4 Total insolubles were quantiíied according to FDA’s methods.
5 At a concentration of 3% at a rotational speed of 60rpm
form more junction zones. This is in keeping with the aggregation of the protein which was

so apparent when the same process was applied to gum arabic. Also as with gum arabic the
effect of pressure reverses the aggregation and delivers a stronger interíacial film at the
suríace of the oil droplet, so increasing emulsion stability.
Control Modiíied
Figure 7. Model soft drinks with 10 % orange oil emulsions sterilized at 90° c for 10 min after
storage at 40° c for 1 vvcck (in glass bottles _________________________
Figure 8