Gelling, curdlan

A process using a microbially gelled biopolymer was developed and used to modify the permeability in coreflood experiments [128]. Curdlan is a microbial carbohydrate with 1,3-P-linkages. Alkaline-soluble curdlan biopolymer was... 

The Gelling Mechanism and Relationship to Molecular Structure of Microbial Polysaccharide Curdlan... 

The extracellular microbial polysaccharide curdlan is essentially a linear homopolymer of 6-(l-3)-D-glucan as illustrated in Figure 1. It is produced from the mutant strain of the bacteria Alcaligenis faecalis and was first isolated and investigated by Harada and coworkers (J -3) who coined the name curdlan to describe the gelling behaviour of the polysaccharide at elevated temperatures. 

Deuterated gel. Dried curdlan powder was mixed into a 2% w/v suspension in heavy water. This suspension was spread on a glass plate and placed in an airtight container, shown schematically in Figure 5. The container was heated to approximately 100°C, thus gelling the polymer. The film was washed in D2O, to stop the rapid loss of D2O from the hot film, and then carefully removed and dried. (All operations except that of heating were carried out in the dry-box.)... 

Figure 8. IR spectra obtained from curdlan sample gelled in water (a) original film (b) film after deuteration (c) rehydrogenated film...

Figure II. IR spectrum obtained from gelling curdlan in DtO...

Figure 12. IR spectra of curdlan after gelling in NaOD and D20 (a) deuterated film (b) rehydrogenated film...

Curdlan Agrobacterium Gels on heating or acidification gelled foods stable salts and acids... 

Curdlan Agrobacterium biobar and Alcaligenes faecalis Food additive (for example, as a thickener or a gelling agent)... 

The polymers such as cellulose, curdlan, xanthan, levan, and dextran that are obtained from the respective bacteria as described in section 10.2 are utilized in various food applications. Cellulose is used in food (nata de coco), and curdlan is used in food as a thickener and gelling agent. Dextran is used in healthy beverages, xanthan is used as a rheology modifier and food additive, and levan is used in food biotechnology. 

Also it has been suggested that curdlan would have utility in foods such as gelled desserts, spaghetti, noodles, dietetic foods, hamburgers, and sausages. 

Scleroglucan (from Sclerotinia sclemtiomm) is a 1 3 -D-glucan with additional 1 —> 6 (3-links (Fig. 13.9) that confer water solubility to it under ambient conditions, but do not significantly interfere with a triple helix gelling process, similar to that of curdlan [46]. Similar polysaccharides can also be extracted from other sources such as waste yeast. 

FunamiT, Nishinari K. Gelling characteristics of curdlan aqueous dispersions in the presence of salts. Food Hydrocoll 2007 21 59-65. 

FunamiT, Funami M.Yada H, NakaoY. Rheological and thermal studies on gelling characteristics of curdlan. Food Fdydrocolloids 1999 13 317-24. 

Curdlan serves as a gelling agent, thickener and stabiliser, it improves water binding capacity, viscoelasticity, masks various... 

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