2. A hydrocolloid is defined as a colloid system wherein
the colloid particles are dispersed in water.
Hydrocolloids are high molecular weight hydrophilic
biopolymer used as functional ingredient in the foods
One of most extensively used additive in the food industry
3. Sources of hydrocolloids
Basically it is a polysaccharide
• Plants- starch (Tapioca, Barley, rice )
• Sea weeds (carageenan)
• Microbes (xanthan gum)
• Plant exudates (gum, gum Arabic)
• Modified biopolymer made by chemical
treatment of cellulose
4. Hydrocolloids as additive in food Industry
•Starch
•Agar
•Pectin
•Alginates
•Carrageenan
•Guar gum
•Gum Arabic
•Xanthan gum
•Cellulose derivatives-CMC
5. properties
• Have neutral taste and utilized in small quantities
• edible and Non toxic
• They provides an unctuous body to fat reduced products
• Biocompatibility, non polluting, low cost
• Enhance the bulk of the product while improving many functional
properties
• Barrier properties
6. starch
Source-corn, wheat, barley, potato and
tapioca
It is polymer of amylose and amylopectin
(25:75)
Gelatinization temperature is
55-75 ⁰C
Use Of Starch- Sausage, battered And
Breaded Products, noodles
7. Pectin
•It is polymer of galacturonic acid
•Main source –peels of apple (15%) and citrus fruits (30%)
•It is good gelling and solidifying agent
•Uses-jem and jellies
Sodium Alginate
•Sodium alginate is an anionic polysaccharide
•extracted principally from the giant kelp Macrocystis pyrifera as alginic
acid and neutralized to the sodium salt.
• It is soluble in hot or cold water and gives somewhat hazy solutions of
neutral pH.
8. Guar Gum
Guar gum is a nonionic
source- endosperm of legume Cyamopsis tetragonolobus
It gives neutral pH Solution in cold water
Xanthan Gum
•Xanthan gum is an anionic polysaccharide derived from the fermentation
of the plant bacteria Xanthomonas compestris
•It is soluble in hot or cold water and gives visually hazy, neutral pH
solutions
9. Carrageenan
•Carrageenan is an anionic polysaccharide
•extracted principally from the red seaweed Chondrus crispus
•Carrageenan is available in sodium, potassium, magnesium,calcium
and mixed cation forms
•Carrageenan solutions are typically clear, and of alkaline ph
Gum Arabic (Acacia)
• Gum arabic is an anionic polysaccharide collected as the
dried exudate from The acacia tree (Acacia senegal)
• it is soluble in hot or cold water and gives clear solutions of
neutral to acidic pH.
10. Hydrocolloids as additives
Polysaccharides and proteins are food hydrocolloids with an
important role in the structure, stability and functional
properties of several processed foods.
Protein carbohydrate interactions determine the functional
properties in foods where proteins are the major ingredients,
such as meat and fish processed products.
11. •Fish Protein solublised by salt and water forms a
continuous matrix
•Some additive can be entrapped within this matrix filling
the gel and exerting their functional effect in restructured
products by
1. Influencing the formation of continuous surimi gel
matrix during thermal inducing gelation
2. Modifying the viscosity, mobility and other properties
of the liquid phase
3. Influencing the appearance and texture of the gel i.e.
particle size distribution, rheological properties and
relative volume fraction of the gel.
15. Experimental set up
• Double filleted oil sardines were taken in the
study
• Chitosan dip treatment was given at rate of 1 %
and 2 % for 10 minutes and one control was
performed.
• Fillets were kept in HDPE boxes and 1-2 ⁰C
temperature was maintained with ice during
whole storage study.
21. conclusion
• Chitosan treatment was found to be effective in
reducing spoilage and extending the self life of
the fillets.
• It also helps to maintain good WHC, reduce
drip loss and textural qualities
• A self life of 8 and 10 days was observed for 1
and 2 % chitosan treated samples respectively
compare to 5 days for control.
Notes de l'éditeur
A colloid is a substance microscopically dispersed evenly throughout another substance.A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium). A colloidal system may be solid, liquid, or gaseous.
