Carrageenan is a hydrocolloid extracted from some red seaweeds belonging to the Gigartina, Hypnea, Eucheuma, Chondrus and Iridaea species. It is used in a wide variety of applications in the food industry as a thickening, gelling, stabilizing and suspending agent in water and milk systems.
Carrageenan is a multifunctional ingredient and it behaves differently in water and in milk systems. In water it shows typical hydrocolloid properties of thickening and gelling, while in milk systems it also has the property of reacting with proteins to furnish additional stabilizing abilities.
Carrageenan has a unique ability to form a wide variety of gel textures at room temperature: rigid or elastic, clear or turbid, tough or tender, heat stable or thermally reversible, low or high melting/gelling temperatures. It may also be used as a suspending, gelling, emulsifying, stabilizing and water retaining agent in other industrial applications.
Carrageenan can be classified according to its structure and chemical properties or according to its production process:

1. STRUCTURE AND CHEMICAL PROPERTIES

KAPPA - rigid and brittle gel, thermo-reversible, high gel strength, showing syneresis.
IOTA - elastic gel, thermo-reversible, no syneresis, thixotropic.
LAMBDA - cold soluble, non gelling, high viscosity.

2. PRODUCTION PROCESS

SEMI-REFINED - opaque gel containing high cellulose and fiber levels, low degree of purity.
REFINED - clear, transparent gel, with a high degree of purity.

RAW MATERIAL

Carrageenan is obtained from several kinds and species of seaweeds belonging to the Rodophyceae class. The carrageenan content of commercial seaweeds varies from 30% to 60% of dry weight, depending on the seaweed species and the sea conditions, such as luminosity, nutrients, water temperature and oxygenation. Seaweeds of different species and sources produce different types of carrageenan such as kappa, iota and lambda.Ê Some species of seaweed may produce a mixed type carrageenan such as kappa/iota, kappa/lambda or iota/lambda. The species that produce kappa-type carrageenan are the Hypnea Musciformis, the Gigartina Stellata, the Eucheuma Cottonii, the Chondrus Crispus and the Iridaea. The species that produce iota-type carrageenan are the Gigartina Teedi and the Eucheuma Spinosum. The species that produce lambda type carrageenan generally belong to the Gigartina class.
Seaweeds are usually harvested manually by fishermen in low depths at low tides or by diving using appropriate equipment. After being harvested, seaweeds are placed under the sun to dry until they reach a humidity level that is ideal for processing.

FUNCTIONALITY AND APPLICATIONS

The uses of carrageenan are concentrated in the food industry. Carrageenan applications are generally divided into milk based systems, water based systems and beverages. However, there are many other applications for carrageenan in a large variety of industrial applications. Carrageenan has many functions according to its uses and applications: gelling, thickening, emulsion stabilizing, protein stabilizing, particle suspension, viscosity control and water retention are just a few.

1. FOOD INDUSTRY

Milk Products

Ice creams, Chocolate milk, Flans, Puddings, Whipped cream, Yogurts, Creamy milk desserts, Cheeses, Dry mix desserts, Coconut milk

Confectionary

Dessert Gel, Jam, Dough sweets, Marshmallows, Gum drops, Comfitures, Meringues

Meat Products

Cooked ham, Imitation meat, Sausage, Canned meat, Hamburger, Pureed Meat, Poultry, Processed Meat

Beverages

Clarifying and refining of juices, beers, wines and vinegars, Chocolate milk, Syrups, Powdered fruit juices, Diet shakes

Bakery Products

Cake icings, Tart fillings, Bread dough

Dressings and Soups

Dry mix salad dressings, Powdered soups, Mustard, White sauce, Ready to eat sauces

2. OTHER INDUSTRIAL APPLICATIONS

Tooth paste, Air fresheners, Pet food , Cosmetics, Paints, Emulsions

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