Seaweed proteins extraction

A useful property of the red seaweed extracts is their abiUty to form gels with water and milk. Kappa-carrageenan reacts with milk protein micelles, particularly kappa-casein micelles. The thickening effect of kappa-carrageenan in milk is 5—10 times greater than it is in water at a concentration of 0.025% in milk, a weak thixotropic gel is formed. 

Alain at AJainic Arid 15 a protein of marine algae and is found in many seaweeds. Its principal source of prepn is as a by-product of the extraction of iodine from kelp, principally from Laminaria digitata. It has been used mainly in Japan, for the prepn of films, fabric dressing, and for thickening jellies. 

Macroalgal extracts possess various proteins and peptides which play an important role in the formulation of new collagen as well as increased skin hydration. In addition, marine red algae increases skin hydration significantly because of the en2ymes and minerals present in the algae which are prominent in Hawaiian Islands. French seaweeds are other... 

The isolation of protein from seaweeds is a difficult task due to the link between polysaccharides and protein within the seaweed matrix. It is described that the extraction of proteins from the tissues of laminarialean algae (Nagai et ah, 2008) or Saccharina japonica (Kim et ah, 2011) is difficult due to high levels of nonprotein interfering compounds, mainly viscous polysaccharides. As a consequence, isoelectric point (Ma et ah, 1996) or ammonium sulfate saturation (Hemandez-Mireles and Rito-Palomares, 2006) or trichloro acetic acid (Barbarino and Louren o, 2005) approaches, which are cormnonly used for protein precipitation, are not completely useful for seaweeds. Thus, to solve this task, different approaches are proposed such as proteolytic treatment of the whole seaweeds followed by filtration and dialysis (Suetsima and Nakano, 2000) or treatment... 

Hydrocolloids are high-molecular-weight hydrophihc biopolymers used as functional ingredients in the food industry for the control of viscosity, gelation, microstructure, texture, flavor, and shelf-hfe. The term hydrocolloid encompasses all the polysaccharides that are extracted from plants, seaweeds, and microbial sources, as well as gums derived from plant exudates, and modified biopolymers made by chemical or enzymatic treatment to be soluble or dispersible in water. The general molecular and functional properties of proteins and polysaccharides are compared in Table 5.1. 

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