1. Lecture XIV NEUTRAL PS’s - CELLULOSICS
Lecture #14 - NEUTRAL PS’s - CELLULOSICS (but not CMC)

2. NEUTRAL PS’s - Cellulosics
HC’s to be covered
Cellulose fiber
Microcrystalline cellulose (MCC)
Methyl & Hydroxypropyl celluloses
Hydroxypropyl cellulose
Others

3. NEUTRAL PS’s - Cellulosics
General Advantages
Uniform properties and specs
Stable prices
Unlimited availability
Low B.O.D
Domestic products

4. NEUTRAL PS’s - Cellulosics
Structure (general)
Macro structure
Micro structure
Ethers

5. NEUTRAL PS’s - Cellulosics
Cellulose “Fibers”
Bundles of
Microcrystals
Paracrystalline
(amorphous) area
Complements of FMC Corp
Cellulose microfibril

6. Structure of Cellulosen OH OH
CH2OH
CH2OH O O O OH O OH OH OH O O O O OH
CH2OH OH
CH2OH

7. Derivatization of Cellulose
CH2OH OH
Alkali cellulose
CH2O–Na+ O
50% NaOH O OH O OH
a-cellulose
1. ClCH2COOH
2. NaOH
CH2OCH2COO–Na+ O O OH O OH
NaCMC

8. Cellulose Derivatives
CH2OR OR 6 5 4 3 2 1
b-D- anhydroglucose unit
R = -CH3 = MC
R = -CH2COONa = NaCMC
R = -CH2(CHOH)CH3 = HPC
R = -CH2(CHOH)CH3 and -CH3 = HPMC
R = -CH2CH2OH = HEC

9. Cellulose Derivatives D.S. = Degree of Substitution
D.S. = moles of substituted material
total moles of polymer(i.e., anhydro glu units)
1. Start w/ 162 g of a-cellulose
2. Rx w/ ClCH2COO-Na+ - end up w/ 200 g of material
3. So, 38 g of ClCH2COO-Na+ grps (MW=81)
4. 38/81 = 0.47 moles of substituted material
5. D.S. = 0.47/1 = 0.47

10. Unsubstituted Cellulosics
Refined Cellulose Fibers (a-cellulose)
Manufacture
Properties
Applications

11. Unsubstituted Cellulosics
Refined Cellulose Fibers (a-cellulose)
Manufacture
Properties
Applications
Microcrystalline Cellulose (MCC)
Types

12. Cellulose products used in foods
a Cellulose
Acid insouble
fraction
Chemical
Derivatization
Chemical
Depolymerization
Wet Mechanical
Disintegration
Soluble
Cellulose
Derivative
Drying
Dispersing Agent
+ Water
Powdered
Avicel
(PH/FD Grades
Colloidal Avicel
Hydrocolloid
Solution
+ Water
Aqueous Colloidal
(RC/CL Grades)

13. Unsubstituted Cellulosics MCC - Powdered
Properties
Water insoluble - very absorptive
Fine, white “flour”
High shear requirement for vis
Concentration limitations
Applications
Bulk filler
Dietary fiber (no calories)
Anticaking agent
Carrier
Extrusion aid
Tableting aid

14. Unsubstituted Cellulosics MCC - “Colloidal”
Properties
Several Co-drying agents available
Dispersible w/ less energy
Bulk-dried - needs homogenization
Spray-dried - needs high speed mixer
Sweet whey addition - dry mixes
Thixotropic gel former
Much reduced “chalky”/drying effect
Applications (see FMC handout)
Heat stable emulsions
Fat sparing applications
Frozen desserts
Aerosol toppings
Dairy-type products

15. Complements of FMC Corp
Colloidal MCC
Dispersion
(Macroscopic View)
Water
MCC
CMC
Complements of FMC Corp

16. Unsubstituted Cellulosics MCC - “Colloidal”
Comparisons of Colloidal MCC to CMC

17. Thixotropic
Gel Former

18. MCC - “Colloidal” Mechanism of Foam Stabilization
Water
Air
Cell

21. Unsubstituted Cellulosics MCC - “Colloidal”
FDA Status
GRAS
Labeling
“Cellulose gel”

22. Benefits vs other Hydrocolloids
Creamy, fat-like mouthfeel (fat sparing) in certain systems
Nearly inert material (minimally affected by heat, pH, salts, etc)
Can often help other hydrocolloids
Completely non digestible - no calories
Abundant raw material supply

23. Liabilities vs other Hydrocolloids
Milky white, cloudy dispersions
Dry, cotton-like mouthfeel at high concentrations
Requires relatively high shear to achieve benefits

24. Substituted Cellulosics Methyl (MC) & Hydroxyprpyl (HPMC) Celluloses
Manufacture
6-OH = most reactive
Solubility
Steric hindrance = stable solutions

25. Substituted Cellulosics M.S. NEEDED TO PRODUCE COLD WATER
SOLUBLE CELLULOSICS
Derivative M.S.
Methyl
Hydroxyethyl
Hydroxypropyl
Carboxymethyl-(CMC) 0.4
NOTE: M.S. = Moles Substituted

26. Substituted Cellulosics Manufacture
Alkali Cellulose
ROH +
NaOH
RO-Na+
H2O
Methyl Cellulose (MC) +
NaCl
RO-Na+
CH3Cl
ROCH3
Hydroxypropyl Cellulose (HPC) O
H2C-CH-CH3 +
RO-Na+
ROCH2-CH-CH3 OH

28. Substituted Cellulosics Methyl (MC) & Hydroxyprpyl (HPMC) Celluloses
Properties
Solubility
Cold water soluble, hot water insoluble
Considerable organic solubility
Surface active
Thermo-Gelation
Good film formers

29. Substituted Cellulosics Methyl (MC) & Hydroxyprpyl (HPMC) Celluloses
Properties

30. Substituted Cellulosics Methyl (MC) & Hydroxyprpyl (HPMC) Celluloses
Properties
Solubility
Cold water soluble, hot water insoluble
Considerable organic solubility
Surface active
Thermo-Gelation
Good film formers

31. TEMPERATURE EFFECT ON VISCOSITY OF VARIOUS GUMS

32. TEMPERATURE EFFECT ON VISCOSITY OF VARIOUS GUMS
X.G.
CARR
S.A.
LBG
CMC
PGA
HMP
GUAR
LMP
KGEL

33. Gelation of 2% aqueous solution of MC. (Heating rate = 0.25oC/min)
Charting Thermal
Gelation
Gelation of 2% aqueous solution of MC. (Heating rate = 0.25oC/min)

34. Equals a methyl ether group
Why Gelation When Hot?
Equals a methyl ether group
Layer of water of hydration surrounds MC molecule
And prevents hydrophobic methyl groups from approaching each other.

35. Equals a methyl ether group
Why Gelation When Hot?
Equals a methyl ether group
Layer of water of hydration becomes smaller when hot.
Does not prevent hydrophobic methyl groups from approaching each other (“clumping together)

36. Substituted Cellulosics Methyl (MC) & Hydroxypropyl (HPMC) Celluloses

37. Substituted Cellulosics Methyl (MC) & Hydroxypropyl (HPMC) Celluloses
Properties
Solubility
Cold water soluble, hot water insoluble
Considerable organic solubility
Surface active
Thermo-Gelation
Good film formers

38. Substituted Cellulosics Methyl (MC) & Hydroxypropyl (HPMC) Celluloses
Applications
Thermo-Gelation
Baked products
Extruded products
Hot temp suspension
Surface active
Whipped Toppings
Frozen Desserts
Good film formers

41. Substituted Cellulosics Methyl (MC) & Hydroxypropyl (HPMC) Celluloses
FDA Status
MC - GRAS
HPMC - Food Additive
Labeling
MC = Methylcellulose or “modified vegetable gum” or “modified cellulose”
HPMC = Hydroxypropyl methylcellulose or “carbohydrate gum”

42. Benefits vs other Hydrocolloids
Thermal gelation - reversible
Quite highly surface active
Non-ionic material
Clear Solutions (cold)
Abundant raw material supply
Good film former

43. Liabilities vs other Hydrocolloids
Gel reverts to liquid upon cooling
Hot "solutions" cloudy
Can produce foaming problems
Susceptible to cellulase enzymes

44. Structural Formula for Hydroxypropyl Cellulose (HPC)
(Courtesy of Hercules Inc.)

45. Substituted Cellulosics Hydroxypropyl Cellulose (HPC)
Manufacture
Typical MS range
Typical M.W. 60, million

46. Substituted Cellulosics Hydroxypropyl Cellulose (HPC)
Properties
Solubility/Viscosity
Cold water soluble, hot water insoluble
Polar, organic liquids solubility
Highly Surface active
Thermoplastic
Film formers
FDA Status (food additive)

47. Substituted Cellulosics Hydroxypropyl Cellulose (HPC)
Applications
Whipped toppings
Edible film coatings/nuts & candies
Limited food applications - many industrial & pharmaceutical, however

48. Benefits vs other Hydrocolloids
Solvent solubility
Highly surface active
Non-ionic material
Clear Solutions (cold)
Abundant raw material supply

49. Liabilities vs other Hydrocolloids
Foaming problems
Precipitates at temps > 40oC
Susceptible to cellulase enzymes

50. NEUTRAL PS’s - Cellulosics
HC’s to be covered
Cellulose fiber
Microcrystalline cellulose (MCC)
Methyl & Hydroxypropyl celluloses
Hydroxypropyl cellulose
Others
Methylethyl cellulose (MEC)
Hydroxyethyl cellulose (HEC)