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Polyguluronic acid chains as found in segments of alginate (2004)

polyguluronic acid structure

Structure of polymannuronic acid segments found in alginate (2004)

Polymannuronic acid structure

Prepared at the 49th JECFA (1997) ,published in FNP 52 Add 5 (1997) superseding specifications prepared at the 44th JECFA (1995), published in FNP 52 Add 3 (1995). Metals and arsenic specifications revised at the 49th JECFA (1997). An ADI 'not specified' was established at the 39th JECFA (1992)

Prepared at the 49th JECFA (1997), published in FNP 52 Add 5 superseding specifications prepared at the 44th JECFA (1995), published in FNP52 Add 3 (1995). Metals and arsenic specifications revised at the 57th JECFA (2001). An ADI 'not specified' was established at the 39th JECFA (1992)

Prepared at the 49th JECFA (1997), published in FNP 52 Add 5 (1997) superseding specifications prepared at the 44th JECFA (1995), published in FNP 52 Add 3 (1995). An ADI 'not specified' was established at the 39th JECFA (1992)

Products: alginate, carrageenan, guar, locust bean gum, pectin, xanthan
Their products are sold under the tradenames: satialgine, cecalgum, algogel, satiagel, satiagum, aubygel, unipectine, satiaxans, verxan

Products: alginate, carrageenan, guar, locust bean gum, pectin, cellulosics, xanthan, systems 
Their products are sold under the tradenames: Grinsted, meyprodor

In 2004 Danisco purchased Rhodia's food ingredient business

http://www.danisco.com/food-beverages/

COMMISSION REGULATION (EU) No 231/2012 of 9 March 2012

Synonyms

COMMISSION REGULATION (EU) No 231/2012 of 9 March 2012

Synonyms

COMMISSION REGULATION (EU) No 231/2012 of 9 March 2012

Synonyms

COMMISSION REGULATION (EU) No 231/2012 of 9 March 2012

Synonyms

COMMISSION REGULATION (EU) No 231/2012 of 9 March 2012

Synonyms

Calcium salt of alginate

COMMISSION REGULATION (EU) No 231/2012 of 9 March 2012

Synonyms

Hydroxypropyl alginate; 1,2-Propanediol ester of alginic acid; Propylene glycol alginate

Products: alginate, carrageenan, konjac, microcrystalline cellulose/cellulose gel, pectin, hyaluronic acid, systems 
Their products are sold under the tradenames: Seagel, Gelcarin, Lactarin, Viscarin for carrageenan, Nutricol for konjac and Protanal for alginates.

http://www.fmcbiopolymer.com/Food

Hydrocolloids can be obtained from a wide variety of sources. The two most abundant polysaccharides are cellulose and starch. Cellulose is the key structural component of trees and is used on a huge scale globally in the pulp and paper industry.

What is Alginate?

Alginate is found in a wide variety of brown seaweeds and is present as a structural polysaccharide. Alginate is made up of a linear block copolymer of α-L-guluronic acid and β-D-mannuronic acid. The blocks vary in size and alternating M and G segments as well as random blocks may also be present.

Production of Alginate

There are essentially two processes for the preparation of alginates. They all start off with similar extraction procedures but vary in the methods used to precipitate the alginate at the end of the process.

Properties of Alginate

Roughly speaking the M to G ratio of the alginate largely controls functionality. Work has shown that a more sophisticated approach linking gel properties to block size produces a better correlation.

Structure of Alginate

Alginate was originally thought to consist of a uniform polymer of mannuronic acid as shown in figure 1. However later studies showed the presence of guluronic acid residues and it is now understood that alginate is a linear co-polymer of β-D-Mannuronic acid and α±-L-Guluronic acid.

Low fat yogurt requires the use of stabilisers to enhance the texture and creaminess of the product. The most common stabilisers used are: gelatine (100 - 250 bloom, 0.2 - 0.5%), pectin (0.05 – 0.20%), modified starch (0.5 – 2.0%), alginate (0.25 – 0.50%), agar (0.8 - 1.1%), carrageenan (0.05 – 0.20%) (Hui, 2007).

Seaweed derived extracts makes up almost 40% of the worlds hydrocolloid market in foods. Carrageenan is the most important seaweed extract with the largest markets being in pet food, dairy and meats. Agar is largely a traditional foodstuff produced in Asia for the local market.

Products: agar, carrageenan, depolymerised alginate, partially hydrolysed guar gum

Founded as Myeong Shin Chemical Ind Co Ltd in 1974 which changed its name to MSC Co Ltd in 1997

http://www.msckorea.com/

Products: alginate, chitosan salts, ultra pure grades of hyaluronic acid (ex Kikkoman Biochemifa Company (KBC), formerly Kibun Foodchemifa)

Their products are sold under the tradenames: PRONOVA (sodium alginate) and PROTOSAN (Chitosan salts)

Pimiento is a variety of chilli pepper. This type of pepper is used as a stuffing in Spanish green olives. Traditionally these red peppers were cut to size and hand stuffed into the olives.

Products: guar, locust bean gum, tara, alginate, starch, tamarind
Their products are sold under the tradenames: Polygum, Polygel

http://www.polygal.ch/index.asp

Prepared at the 49th JECFA (1997) , published in FNP 52 Add 5 (1997) superseding specifications prepared at the 44th JECFA (1995), published in FNP 52 Add 3 (1995). An ADI 'not specified' was established at the 39th JECFA (1992)

Prepared at the 49th JECFA (1997), published in FNP 52 (1997) superseding specifications prepared at the 44th JECFA (1995), published in FNP 52 Add 3 (1995). An ADI of 0-70 mg/kg bw was established at the 41st JECFA (1993)

Restructured onion rings are made with alginate as the calcium gelling allows for the rings to be easily formed and more resilient to handling during the battering and crumbing stage. 

Ascophyllum nodosum

Source Cybercolloids (2003)

Ascophyllum

Shore cast Laminaria off the coast of Ireland (2004)

Shore cast laminaria

Laminaria on the shores of Ireland.  Source CyberColloids (2004)

Shore cast laminaria

Shore cast Laminaria (2004)

Laminaria

Mixed seaweeds growing in the intertidal region on the coast of Ireland (2004)

Mixed seaweed

Prepared at the 49th JECFA (1997) , published in FNP 52 Add 5 (1997) superseding specifications prepared at the 44th JECFA (1995), published in FNP 52 Add 3 (1995). An ADI 'not specified' was established at the 39th JECFA (1992)

Products: alginate

Manufacturers and Exporters of Liquid Seaweed Extract, Seaweed Extract Powder, Seaweed Powder, Liquid Seaweed Fertilizer, Spray Dried Seaweed Extract,Seaweed Extract Granules, Sodium Alginate, Alginic Acid and Calcium Alginate in India

Seaweeds

Algae are one of the worlds oldest lifeforms, being present in the pre Cambrian era (Engel, 1961). Although the so called higher plants developed stems, leaves and a root system once the marine algae had utilised light in photosynthesis their development seems to have come to a halt.

Bacterial alginate

Alginate can be produced by a microbial fermentation using bacteria such as Azobacter Vinelandii and Pseudomonas Aeruginosa (Linker and Jones 1964, Gorin and Spencer 1966). These bacteria produce a polysaccharide with a structure resembling alginate, differing only in that there are acetyl groups on a portion of the C2 and C3 hydroxyls.

Alginate production

Alginate, as mentioned before, is found in all types of Phaeophycaea and apart from being a structural polysaccharide and providing rigidity to the algae it also helps prevent the dessication of those plants expose to air at low tide. Alginate occurs in brown seaweeds in the intercellular mucilage and algal cell wall as an insoluble mixed salt.

Structure - Early work

Alginic acid was discovered, first extracted and patented by Stanford in the 1880's (Stanford 1881 and 1885). the patent explains how alginate can be extracted by soaking seaweed in water or dilute acid, extracting with sodium carbonate and then precipitating the alginate out of solution with acid.

Structure - M/G ratios

The usual method for the determination of the ratio of the two uronic acid types is by hydrolysis of the chain followed by analysis of the sugar components.

Structure - block structure

The presence of three different types of polymer segment has been shown by mild acid hydrolysis (Haug et al 1966, 1967a, 1967b). one type of segment consists entirely of guluronic acid residues, one consists entirely of mannuronic acid residues and the third consists of an alternating sequence of mannuronic and guluronic acid residues.

Structure - Poly M

Further fine structure information has been obtained from the action of certain alginate lyases upon the alginate chain. An extracellular poly α-L-guluronate lyase was used to degrade the α-L-guluronic acid and random segments and subsequently measure the chain length of the poly β-D-mannuronic acid blocks.

Structure - Poly G

The polyguluronic acid segments are very different to the polymannuronic acid segments. The guluronic acid residues are in the 1C4 conformation and are therefore diaxially linked along the polymer chain. This gives the ribbon structure of the polymer a buckled, as opposed to flat, conformation.

Structure - Tertiary structure

The tertiary structure of alginate has been comprehensively reviewed (Morris, 1986). Alginate adopts an extended, ribbon like conformation, in the solid state, being a two fold structure for the free acid form (Atkins, 1973) and a three fold structure in the salt forms so far studied (Mackie, 1973).

Products: agar, carrageenan, konjac, alginate

Yantai Sheli Hydrocolloids Co., Ltd., is a wholly-owned subsidiary of Kam Yuen International Company

http://en.ytxieli.com