Characteristic
Sodium alginate is also soluble in water but it becomes insoluble at low pH or at high concentrations of calcium as alginic acid or calcium alginate are formed.
Many foods are low in pH, such as fruit drinks, dressings, fermented foods, and calcium rich dairy products. Sodium alginate cannot be used successfully to thicken or stabilize these foods.
Propylene Glycol Alginate (PGA) can be used in such areas where sodium alginate does not work.
PGA becomes an acidic aqueous solution when dissolved in water. It can be dissolved even in acidic foods, resulting in thickening and stabilizing effects.
Due to masking by the propylene glycol group, the carboxyl group does not dissociate in water making it difficult to crosslink even in the presence of calcium ions, and therefore PGA can be effectively used as a stabilizer for dairy products and in similar applications.
In addition, PGA has a lipophilic propylene glycol group added to hydrophilic alginic acid giving a surface-active effect not found in other alginates.
PGA is a unique polymeric polysaccharide that functions not just as a thickener but also as an oil/water emulsion stabilizer.
PGA solutions have a range of properties for various applications which depend on the proportion of esterified carboxyl groups in the structure.
The number of esterified carboxyl groups is expressed as the degree of esterification and is controlled according to the application.
Application
Food Applications
PGA is not gelled with polyvalent cations and is stable in the pH3 – 5 range. It is used as a thickener and stabilizer for foods which contain calcium or low pH.
One application is as an emulsion stabilizer for salad dressings where PGA is used in combination with xanthan gum.
Another application is a dispersion stabilizer for acid milk beverages, where PGA is used to avoid precipitation.
One of the unique uses of PGA is as a foam stabilizer for beer. Adding a small concentration of PGA to fermented beer produces and maintains a fine foam when the beer is poured into a glass.
PGA is also used to improve the texture of bread and noodles. The effect of adding alginate to bread dough is remarkable, and excellent performance such as volume increase and elasticity improvement is observed.
Safety
PGA is evaluated by JECFA; it is different from alginic acid and its salts because PGA has propylene glycol in the structure.
ADI (Acceptable Daily Intake) of PGA is 0~70mg/kg bw.
PGA is safe to use and free from BSE, GMO, Allergens, etc., as it is derived from natural seaweed.
Grades
Selection Guide (Typical Products)
Food / Pharmaceutical grade
KIMILOID - Emulsion stabilizer
Viscosity (1% solution at 20℃) | |
---|---|
LVC | 70 - 170 mPa・s |
HVC | 200 - 600 mPa・s* |
LLV | 15 - 35 mPa・s |
NLS - K | 30 - 60 mPa・s |
LV | 60 - 100 mPa・s |
MV | 100 - 150 mPa・s |
HV | 150 - 250 mPa・s |
KIMILOID - Beverage foam stabilizer
AB | 10 - 40 mPa・s |
KIMILOID - Beer foam stabilizer
Viscosity (2% solution at 25℃) | |
---|---|
BF | 50 - 200 mPa・s |