By: Michelle B.

Phycocolloids are one of several starch like chemicals found in both Red Algae (phylum Rhodophyta) and Brown Algae (phylum Phaeophyta), which are two different types of seaweeds. They are extracted from the cell walls of certain seaweeds and used mainly for their colloidal properties in the way that they transitions between their fluid and solid state. Phycocolloids act like gelatins and are used in many common subjects as emulsifiers, stabilizers, thickeners, and as an agent to help the maintenance of moisture. There are three types of phycocolloids: alginates, agars, and carrageenans.


Algin (alginic acid) is extracted from brown algae. Kelp, which holds algin, is commonly harvested off the coasts of both Japan and California. Kelp is what makes algin the most commercially important phycocolloid. They help in the creation of rubbers and textiles, and the salts from algins make a clear thin film used commonly as a thickener as used in soups or sauces.
Agar is extracted from red algae. It is used in microbiology in place of gelatin for culturing because of its ability to remain semi-solid from zero degrees Celsius to seventy degrees Celsius, it is easy to mix and poor, it is firm, it has good clarity, and in opposition to gelatin most organisms can't digest agar. Also agarose gel created with agars is now replacing starch gels used in laboratories. It is also used in things such as icings, canned meets, or as a clarifying agent in beers and wines.
Carrageenan is a lot like agar, because it too comes from red algae. It is extracted for its gelatin properties. Carrageenan is used as a stabilizer of emulsions. It is also used in suspensions, foams, and to control crystal growth. It is commonly used in pharmaceuticals, cosmetics, and in coatings like paints or inks. It can also be found in edibles such as ice creams and puddings.
Phycocolloids are found in five main groups of common categories that can be seen in everyday stores.
Non Dairy
  • Whipped Toppings
  • Cheeses
  • Instant Breakfasts
  • Milk Shakes
  • Custards
  • Puddings
  • Ice Cream
  • Flans
  • Yogurt
  • Chocolate Milk
  • Evaporated Milk
  • Mayonnaise
  • Egg Nog
  • Jellies-Jams
  • Frozen Foods
  • Syrups
  • Low Calorie Foods
  • Relishes
  • Meringues
  • Fruit Juices
  • Sauces - Gravies
  • Salad Dressings
  • Pastry Fillings
  • Icings
  • Candies
  • Jello
  • Anti drying agent in bread/pastry
  • Air Freshner Gels
  • Welding Rods
  • Castings / Impressions
  • Adhesives
  • Cleaners
  • Explosives
  • Paper Sizing - Coating
  • Textile Dyeing
  • Photographic Film
  • Shoe Polish
  • Rubber Processing
  • Tanning Industry
  • Paints
  • Ointments
  • Capsules - Tablet Coatings: make slow release drugs
  • Anti-Coagulants
  • Stiffening agent for media to grow bacteria - mold
  • Dental Impression Molds
  • Ulcer Medicine
  • Lotions
  • Cosmetics
  • Skin Makeup
  • Toothpaste
  • Laxatives
  • Shaving Soaps

Related Links
Simple list of the uses of the three Phycocolloids.
Straight to the point information on the three types of phycocolloids including examples of species which they are extracted from.
Informational page which highlights the ecological and commercial importance of phycocolloids from algae.


More Phycocolloid Pages