¡ñ Unique Properties
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KGM has the highest molecular weight and viscosity among any dietary fiber known to science,and has extremly high density.As well known,viscosity is the most important quality of soluble fiber,which is usually referred to the functions of reducing the increased blood sugar level after a meal and it¡¯s general stabilisation.The greater the viscosity,the greater the effect.
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KGM has highest water holding capacity,it can binds 200 times of its original volume and turn it into viscous liquid.
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Because of its linked b-1-4 structure of glucose and mannose,KGM is not affected by human digestive enzymes in the small intestine and contributes no calaries.
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With no fat,sugar,starch or protein.
¡ñ properties & Functions
KGM has the physicochemical properties of water solubility, thickening, stabilizing, jelling, suspending, film-forming, etc.
- Water solubility:
KGM can be readily dissolved in cold or hot water and can absorb water as much as 100-200 fold in volume. Its water solution is a pseudo-plastic liquid, characterized by shear thinning, i.e. the apparent viscosity is lowered with the increase of shear rate. Therefore, test of viscosity should be carried out under strictly controlled conditions.
- Thickening:
Owing to its properties of great molecular weight, high hydration capacity and freedom of electric charges, etc., KGM is a good thickening agent. The viscosity of 1% KGM solution is as high as 5000-40000 mpa, the highest among all natural thickening agents and much higher than that of guar gum and fruit gum, which means that, in practical applications, konjac gum of very low concentration can achieve satisfactory thickening and structure-improving results. Konjac gum has the capacity of maintaining the stability and structural moistening of goods after heating, while other thickening agents fall short of such capability.
- Stabilizing:
In comparison with other thickening agents such as xanthan gum, guar gum, locust bean gum, etc., konjac gum is of non-ionic type and is therefore little influenced by the salt in the system. At ambient temperature, konjac gum remains stable even if the pH value drops to a level below 3.5. When konjac gum is used instead of locust bean gum as the stabilizing agent and is added to ice cream, cheese and other diary products, it will stabilizing their quality by preventing the development of ice crystals.
- Jelling:
KGM has the unique jelling ability. By putting a little alkali into 2%-3% konjac solution, heating to 85¡æ and leaving it alone for two hours, an elastic, solid and irreversible gel will be formed. This kind of gel has unmatched high thermo-stability and is hard to melt even under prolonged heating. Other hydrophilic gums such as guar gum and carrageenan cannot form such gel. The test of forming thermo-stable gel can differentiate konjac gum from guar gum, carrageenan and other hydrophilic gums. By utilizing its thermo-irreversible property of konjac gum, it may be used to make a variety of foods, such as konjac cake, konjac noodle, animal food-imitating food, vegetarian food, etc.
- Synergistic Effect with Other Hydrophilic Gums
Konjac gum and xanthan gum do not gelatinize when used alone but can form gel when used in combination under certain conditions and can result in the strongest synergistic effect at pH 5. When konjac gum and xanthan gum is formulated at the ratio of 3:2, the intensity of the produced gel is the highest. The gel produced by combining konjac gum and xanthan gum is reversible and can turn into sol when heated, which can be restored to gel at the indoor temperature.
The combination of konjac and carrageenan can also result in obvious synergistic effect. When konjac and carrageenan are formulated at a ratio of 1:4, the intensity of the produced gel reaches the highest; when formulated at a ratio of 4:1, the gel reaches the maximum viscosity. The carrageenan colloid added with konjac gum features excellent elasticity and tenacity.
Besides, konjac and guar gum can also produce obvious synergistic effect if used together.
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