Practical applications of gums and stabilisers in dairy Foods

Transcription

Practical applications of gums and stabilisers in dairy Foods
Practical applications of gums
and stabilisers
in dairy Foods
Matt Golding &
Lara Matia-Merino
IFNHH
Content
• Definitions
• Structure, type and function
• Hydrocolloids as food additives
– Examples of dairy applications
– Synergistic aspects
– Processing
– Trouble shooting
Functional Ingredients in Dairy
Terminology: Hydrocolloids, Biopolymers
cular-weight water-soluble polymers
 Types: Polysaccharides or Proteins (disordered or globular)
surface-active stabilizing polymers
Proteins: emulsification and foaming properties
Polysaccharides: water-holding
Some Hydrocolloids are used as emulsifying agents
e.g., gum arabic, gelatin.
Food Hydrocolloids
High-molecular-weight hydrophilic biopolymers that can control
microstructure, texture, flavour and shelf-life
•Many polysaccharides extracted from plants , seaweeds, microbial
sources (agar, carrageen, xanthan..) and gums (gellan, guar, acacia
gum) and modified starch or cellulose (chemically or enzymatically)
•Protein gelatin
Hydrocolloids at a Glance
Hydrocolloids as functional ingredients
can be found in many foods
Food Hydrocolloids
Plant
Animal
Microbial
Seaweed extracts
Red (agar, carrageen..)
Brown (alginates..)
Gelatin
Xanthan,
dextran,
curdlan, gellan,
pullulan
Exudates (gum arabic, tragacanth, gum
karaya
Seeds (locust bean gum, guar gum, tara
gum..)
Roots (konjac)
Plant extracts (pectins, B-glucan)
Cellulose derivatives
Neutral
Charged
Guar gum, LBG, konjac,
curdlan, MCC
Pectin, alginate, PGA, carrageenan,
xanthan, gellan, agar, gum arabic
Structural assembly of polysaccharides
www.nottingham.ac.uk/ncmh
Hydrocolloids in one page
Food Hydrocolloids:
• Stabilizer
– Maintains the homogeneous dispersion of two or more immiscible
substances in a food.
• Thickener
– Increases the viscosity of the continuous phase. The size and
structure of these large molecules (polysaccharides) create viscosity
at fairly low concentrations (usually less than 1%)
• Gelling agent
– Forms a network gel by chain-chain, chain-solvent crosslinks
Functionality in dairy products
Thickening, gelling, water binding, emulsion stabilization, foam
stabilization, milk protein stabilization, prevent syneresis, prevent of ice
recrystallization
STARCH, CMC, GUAR, LBG, PGA, XANTHAN
Selecting a
hydrocolloid
PECTIN, CARRAGEENAN
1
WHAT IS THE GUM’S MAJOR FUNCTION?
1. THICKENING/VISCOSITY
3
START
HERE
2. SUSPENSION OF PARTICULATES
(YIELDPOINT)
3. GELLING
4. PROTEIN STABILIZING
4
2
pH OF FINAL
PRODUCT
XANTHAN, PGA
BELOW
ISOELECTRIC
pH
LM PECTIN
CARRAGEENAN
PECTIN
AROUND
ISOELECTRIC
pH
CMC
ABOVE
ISOELECTRIC
pH
CARRAGEENAN
Gum types commonly found in dairy applications
Applications of guar and
LBG
APPLICATION
Ice Cream
Cream cheese
Baked goods
Pastry fillings
Soups, sauces and marinades
Meringues
• Excellent viscosifying properties
• Good tolerance to salt and pH
FUNCTION
Ice crystal and Viscosity
control. Fat mimetic.
Speeds up coagulation,
Improved moisture
binding and texture.
Improved yield and
extension of shelf life.
Viscosity and syneresis
control.
Viscosity control.
Stabilisation and
syneresis prevention.
Carrageenan
APPLICATION
FUNCTION
Chocolate milk
Cocoa suspension and mouth
feel.
Improve succulence, yield and
slice ability.
Provides a transparent flexible
glaze that eliminates syneresis.
Gelling agent and syneresis
control. Provides body and
creaminess.
Viscosity control, improves
foam structure and body.
Suspends insoluble materials,
improves mouthfeel and helps
stabilise emulsions.
Suspends particulates,
improves texture and mouth
feel.
Whey off protection. Texture
modification. Viscosity control.
Gelling agent and syneresis
control.
Gelling agent. Allows reduction
in dairy protein levels. Cost
reduction.
Improves succulence and yield.
Prevents shrinkage upon
cooking
Ham injection
Nappage
Hot fill Dairy dessert
Instant mousse
Applications of carrageenans
Thickened milk drinks
Oil free dressings
Ice Cream & Sorbet
Flans
Processed cheese
Ground meat emulsions
Interactions with proteins
• k-Carrageenan stabilizes milk k-casein products due to its charge interaction
with the casein micelles (~200 nm diameter); their incorporation into the network
preventing whey separation.
• k-Carrageenan’s ability to complex with milk proteins
leads to the formation of a weak thixotropic gel
structure which will suspend cocoa in chocolate milk at
0.02% and form milk gels, such as flans, at 0.20%.
• k- Carrageenan is also used as a binder in cooked
meats, to firm sausages and as a thickener in
toothpaste and puddings.
Typical dairy dessert (neutral pH)
Milk
81.5-83.0 wt%
Sugar
8.0-12.0 wt%
Skimmed milk
powder
Starch
1.8 wt%
Carrageenan
0.15-0.25 wt%
Flavour
0.025 wt%
Colour
0.005 wt%
1.5-4.5 wt%
Electrostatic interaction between k-casein and k-carrageenan has
long been exploited for stabilizing dessert milk products.
Xanthan gum
Apparent viscosity (Pa.s)
100
0.5% xanthan
0.7% Guar gum
10
1
0.1
0.01
0.01
0.1
1
10
Shear rate (1/s)
100
1000
Xanthan – applications in food
APPLICATION
Oil - Water dressings
Syrups and toppings
Baked goods
FUNCTION
Emulsion stabilisation and viscosity
control.
Viscosity control and cocoa
suspension.
Prevents lump formation during
kneading and improves dough
homogeneity.
Pastry fillings
Viscosity and syneresis control.
Soups, sauces and marinades
Whipped creams & mousses
Instant mixes
Viscosity control.
Air cell stabilisation.
Rapid thickening, suspension and
provides body
Polysaccharide applications in ice cream
• Interact with proteins (3D network)
• Increase viscosity of the liquid mix
• improve whippability
• increase overrun,
• reduce serum separation (wheying off)
(Molecules binds the liquid (serum) as the ice
cream starts to melt)
• Contribute to body, texture, chewiness, creaminess,
mouthfeel and eating quality (cold and warm-eating).
• Reduce the rate of meltdown, reduce moisture
migration
• Shape retention on melting
Locust bean gum (410) – stabilises ice crystals
(forms cryogel), maintains quality on temperature
cycling, promotes viscosity (0.05 – 0.3%)
K-carrageenan (407) – promotes viscosity, stabilises mixes, prevents
wheying off (0.02%)
Guar gum (412) – promotes viscosity, thickness and body
(0.05 – 0.2%)
Xanthan (415) – cold hydrating viscosifier for soft-ice
Stabiliser
Locust bean gum
Guar
Carrageenan
Alginate
Agar
Xanthan
Recommended
dispersal temp Dosage level
E number (° C)
(%)
410
412
407
401
406
415
80
20 - 80
>55
80
>90
ambient
0.05 - 0.3
0.05 - 0.3
0.02 - 0.15
0.1 - 0.5
0.1 - 0.5
0.1 – 0.3
Microcrystallinecellulose (MCC) – hydrolysed
cellulose
• MCC crystals do not dissolve in water,
but the colloidal form hydrates to form
thixotropic gels that can stabilize foams,
replace fat, and control ice-crystal growth
• Thixotropy– gels readily break down with shear; when the shear is
removed, the gel will reform over time with minimal loss to viscosity.
• Foam Stability– MCC network thickens the
water phase between air cells and acts as a
physical barrier to maintain the air cells in
suspension.
• Heat Stability – MCC is stable during heat
processing, including baking, retorting, UHT
processing and microwave heating with minimal
loss in viscosity.
• Shorten Textures– shorten textures or add body without creating a
gummy or pasty texture  cleaner mouthfeel and excellent flavor release.
• Suspend Particles – the 3-D matrix is useful in suspending particulates
e.g. calcium carbonate
• Replace Fats and Oils – mimics the flow behaviour of oil emulsions
•Control Ice Crystal Growth – the 3-dimensional matrix of colloidal MCC
and the surface area of the microcrystals retards ice crystals growth
during freeze/thaw cycles. Generally effective in maintaining the three
phase system of water/fat/air.
• Opacity – insoluble cellulose crystallites act as opacifiers and can add
whiteness to products.
Uses of MCC
Application
Function
Fortified milk
Long term suspension of
insoluble material. Improves
creaminess
Improves creaminess and
opacity. Reduces meltdown.
Improves mouth feel,
creaminess and opacity.
Stabilises emulsion and
improves cling.
Improves cling, reduces fat
absorption during frying and
sogginess
Long term Cocoa suspension
and mouth feel.
Stabilises foam structure and
emulsion.
Reduces boil-out, improves
cling and opacity
Low fat Ice Cream
Low fat salad dressings
Batters & Breadings
Chocolate milk
Whipped toppings
Bake-stable fillings
Hydrocolloids in other dairy products
Fermented (Cultured) Dairy Products
•
•
•
•
•
•
Butter Milk
Cottage Cheese
Cream Cheese
Sour Cream
Yogurt
Processed cheese
Cream cheese
Ingredient
%
Pectin, starches,
modified starches,
carrageenan, pectin,
LBG, gelatin
• Fat, protein
replacement
• Texture
enhancement
• Stabilisation
1-Dry blend salt + LGB
2-Mixture is added to fresh cream
cheese with agitation
3-Pasteurization
4-Hot fill containers, fridge
Salt
0.8
Locust bean gum
0.2
Standard fresh
cream cheese
99.00
LBG is used to prevent syneresis
throughout its shelf life
Pectin
•
Gelling (Jam, Jelly, confectionary….)
•
Viscosity (beverage, fruit preparations,
culinary…..)
•
Protein stabilisation (acidified protein drinks,
heat treated beverages….)
•
Syneresis control (yoghurt, desserts, mousse…)
•
Health benefits (fiber source, cancer
prevention…)
Applications of pectins
APPLICATION
FUNCTION
Jams, Jellies and Marmalades
Formation of a gel
network.
Bake-stable fruit preparations
Formation of a Bakestable gel network.
Soft drinks
Stabilising turbidity in
soft drinks.
Yoghurt drinks
Protective colloid.
Dietary fibre enrichment
Positive effect on
serum cholesterol level.
Fruit jelly confectionery
Formation of a gel
network.
Pectin
• HM Pectin ≥ 50% DE
• LM Pectin < 50% DE
• LMA Pectin
Polymer of partially methylated
galacturonic acid (31% DE)
(degree of esterification) and
(17% DA) degree of amidation
•
•
HMP casein dispersion
stabilizer (yoghurt or milk/fruit
juice drinks)
LMP gelling of milk or dessert
products (~0.6 ̶ 0.9%) by
interaction with calcium. Low
sugar/acid products
Low Methoxyl versus High Methoxyl pectin
Gelation of LM pectin
Gelation of HM pectin
Ca+2
Tend to gel in the presence of
calcium, so it will gel with Ca+2 in
milk
Tend to gel at low pH and in
the presence of high [sugar]
Used in yoghurt/dairy dessert
Used in jams and AMDs
Acid Milk Drinks (AMDs) Formulations
• Fruit milk drinks
• Yoghurt drinks
• Butter milk
―Acidified protein liquid system
with stability and viscosity
similar to natural milk‖
• Whey drinks
They are composed of:
• Kefir
an acid dairy phase (fermented base)
or a neutral base (milk, soy-milk, etc)
with an acidic medium (fruit phase:
pulp, fruit concentrate, etc) which can
be flavoured.
sugars and stabilizers are added
HM Pectin in Acid Milk Drinks
Pectin + Casein Interaction
AMDs need addition of stabilizer: (HM Pectin)
The optimum pH range for interaction between HM pectin and
casein is 3.6 to 4.2
1- No pectin
• Casein micelles lose stability towards the pI 4.6 and they
aggregate, below pH 4.6 they are slightly positive
2- Low pectin concentration (< 0.2%)
• Pectin is still negatively charged at pH 4.0
• Pectin cover casein micelles from around pH 5.0
and neutralise casein positive net charge
• Bridging flocculation and instability
AMDs need addition of stabilizer: (HM Pectin)
3-Pectin critical concentration
• Casein micelles are fully covered by pectin
• charge of dispersed particles slightly negative
• solution viscosity is minimum
4- High pectin concentration
• additional concentration of pectin is responsible for viscosity
increase
•Weak gel is formed with casein particle as nodal point
•Steric stabilization of the beverage
What matters for thickening
Polysaccharide thickeners
• The most efficient thickeners are;
•
•
•
•
Linear (e.g. cellulose derivatives)
High molecular mass (e.g. alginate)
Charged (e.g pectin)
Rigid (e.g. xanthan)
• However – non ionic polysaccharides are less
sensitive to salt and pH
What matters for gelling
Factor
Range of values
Example
Serving
temperature
Cold (5 ºC and below)
Chilled
Room temp (about 20 ºC)
Kitchen temp
Hot (50 ºC and above)
Serve hot
Clear/transparent
Aspics, dessert jellies
Opaque
Custards, mousses
Alkaline (>8)
Egg whites
Neutral (6–8)
Most vegetables and meats
Mildly acidic (3–6)
Fruit juices, purees
Very acidic (<3)
Lemon juice, vinegars
Thermo-reversible
Melts with heat and resets when chilled
Thermo-irreversible
Sets with heat and does not melt
Hysteresis
Melts and sets at different temperatures
Ions are required
Calcium to set alginate
Slow and long-lasting
High-fat gels and starches
Fast and short-lived
Gelatins, pectins, gellans
Opacity
pH
Setting
Flavour release
What matters for gelling
Factor
Range of values
Example
Mouthfeel
Creamy
Cream sauces
Sticky
Syrups
Slippery
Noodles
Soft, rubbery
Hard-boiled egg white, High-acyl gellans
Medium
Aspics, gelatins
Stiff, brittle
Low-acyl gellans, agar gels
Liquid when sheared
Fluid gels
Soft gel
Gelatin gels
Stiff gel
Páte de fruit
Very stiff gel
Gummy bears
Dried gels
Films
Elasticity
Stiffness
Origin
Hydrocolloid-polysacch.
Example
Note
From fruits
High-methoxyl pectin
Fruit jellies
Low-methoxyl pectin
Low-sugar pate de fruit
Fruit pectin gels set in the
presence of high sugar
concentration or calcium
Agar
Yôkan, hot savory gels
Forms firm brittle gels with
almost any liquid
Alginate
Spherification
Gels in the presence of calcium
Carrageenan (kappa,
iota)
Eggless custards, yoghurt and
dairy gels
Gels best in dairy solutions
Aloe Vera
Dairy gels
Mastic
Dondurma (Turkish ice
cream)
Gum arabic or acacia gum
Chewing gum
Gum tragacanth
Sugar craft
Forms malleable gels with
cooked sugar
Locust bean gum
Dairy gels
Makes elastic gels with
xanthan gum
From seaweed
From plant sap
or resins
From plant seeds
Guar gum
From
microorganisms
Cellulose gums
High and Low-acyl gellan
High= elastic, opaque
Low= brittle, cleasr
xanthan
Elastic gels with LBG
Hydroxypropyl
methylcellulose
Onion rings, gel noodles
Methylcellulose
Custards, baked goods..
Forms elastic gels
Gels at low concentrations; can
add unpleasant flavours
Combination of hydrocolloids
• Mixtures of hydrocolloids may act synergically
to increase viscosity or antagonistically
to reduce it.
Some reasons:
• Optimisation of cost of final product
• Development of new texture
• Improvement of sensorial properties
• Low fat foods
• Reduction of syneresis
• Stabilisation of emulsions
• Control ice crystals formation
• replacement of gelatine
Synergistic gelation - occurs when two hydrocolloids are combined
1. LBG and xanthan
•
e.g. LBG (non-gelling) and xanthan gum (weak gel).
•
If LBG and xanthan at sufficient concentration, heated to 70 C (158 F), and
allowed to cool, a rubbery but rigid gel results.
•
As little as one part LBG in 500 parts xanthan (or vice versa) creates a gel if
their total concentration in water is 0.5—1%.
•
Similarly, xanthan gum and Tara gum gel when combined.
2. Agar and alginate
•
Agar has less gel strength in the presence of sodium alginate or (to a lesser
extent) gum karaya.
3. Agar and LBG
• Agar has more gel strength in the presence of LBG or (to a lesser extent)
cellulose gum.
4. LBG and K-carrageenan
•
LBG greatly modifies the texture of a K-carrageenan gel, making it more
elastic with a higher break strength, less brittle, and less prone to syneresis.
5. Alginate and Pectin
•
High-methoxy pectins are only able to form gels at high sugar solids levels
within a narrow pH range. When a sodium alginate is included, gel formation
takes place at low solids and below pH 3.8 the gel is reversible, a property
used commercially in jelly topping.
•
The alginate-pectin synergism is one of very few interactions for alginate with
other hydrocolloids, and so far the only one of commercial value.
•
The gel temperature of the algin—pectin gel mixture increases as the
system’s pH is lowered.
Synergism Kappa carrageenan
and LBG
Synergism xanthan gum
and LBG
Hydrocolloid Dispersion Method
1. Dry blend (e.g. approx. 5 parts sugar with 1 part
hydrocolloid)
2. Disperse in oil (non-solvent)
3. High shear mixing (e.g. using a Silverson mixer)
4. Mixing equipment (e.g. triblender)
Silverson High Shear Mixer
Gum arabic (emulsifier + stabilizer)
C
C
C
P
C = hydrophilic carbohydrate
blocks (ca. 2  105 Da)
P = hydrophobic protein backbone
P
 ‘Wattle blossom’ model of Acacia
C
C
(E414)
senegal in aqueous solution — a natural
protein–polysaccharide conjugate
emulsifier
C
C
P
oil
C
P
 Adsorbed at the oil–water interface
In soft drinks, instability known
known as NECK RING
Problem solving
Problem solving
Problem solving
Acknowledgments
Mr. Rod Bennett
Dr. Sung Je Lee
Dupont Nutrition & Health
A.P. Kelvin Goh
Hawkins-Watts