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4 Alginates
4.7.1 Alginates in Food
One of the widest applications of alginate is in food. Its excellent gelling and
viscosity-enhancing properties make it suitable as a thickening, gelling agent, emulsion stabilizer and texture modifier in foods such as dressings, ice creams, noodles,
beer, jelly and others. Alginate is FAO, WHO and FDA approved for food applications. The forms of alginate used in the food industry are alginic acid, sodium
alginate, potassium alginate, ammonium alginate, calcium alginate and propylene
glycol alginate. These are labeled E400–E405, respectively Featherstone (2015).
Alginates in food industry allow storage of food in cans, jars, hard gels, etc.
for longer periods while retaining or even improving the texture and consistency.
In modifying the texture, retaining moisture and improving the texture of foods,
alginate serves the role of extending food shelf life and preserving the organoleptic
properties over the food shelf life period. This has the economic and environmental
impact of reducing food waste and serving as an alternative to more energy-intensive
preservation methods such as freeze drying or freezing. Foods such as vegetables,
fruits, cheese, seafood and meat can be stored at room temperature when preserved
with alginate in methods such as canning and sealing.
The use of alginate can also be used to reduce the amount of other components
needed due to its superior viscosity enhancing and gelling property. For example,
where 5% starch is used as a thickener, about 4% of the starch can be replaced
with 1% low viscosity sodium alginate with calcium salt. This allows processing
such as improved heat transfer during heat sterilization and mixing, unlike starch
which is more sensitive to heat. The sodium alginate then reacts with the calcium
salt over time after processing to achieve the desired viscosity in the sealed food. The
viscosity difference can be up 10x Featherstone (2015). So with sodium alginate, you
can process the food at lower viscosity for easy mixing and heat transfer and then
package and seal while the sodium alginate in the presence of calcium salt continues
to increase in viscosity over a period of several hours or days.
Sodium alginate is the alginic salt which is soluble in water and is used in the food
industry for its viscosity-enhancing property. It also forms a non-thermoreversible
stable gel at room temperature on addition of calcium salt such as calcium chloride
or other polyvalent metal ions. This property makes it useful as a thickener, gelling
agent and stabilizer in the food industry. Polypropylene glycol alginate is also used
in the food industry as an emulsion stabilizer and stabilizer.
Even better than biodegradable packaging is edible packaging in the form of
films or coatings. Being indigestible edible polysaccharide alginate packaging can
contribute to the fiber intake. Alginate can serve as a sacrificial moisture agent,
whereby the moisture which would otherwise evaporate from the food evaporates
from the alginate coating instead such that the food retains its moisture content.
Alginate is used to produce edible films with thickness no more than 0.3 mm which
can be eaten with the food or easily removed. This packaging is to be as safe as the
food itself and should not alter the organoleptic properties of the food. Methods for
producing alginate films include solvent casting and extrusion (Olatunji and Olsson
4 Alginates
4.7.1 Alginates in Food
One of the widest applications of alginate is in food. Its excellent gelling and
viscosity-enhancing properties make it suitable as a thickening, gelling agent, emulsion stabilizer and texture modifier in foods such as dressings, ice creams, noodles,
beer, jelly and others. Alginate is FAO, WHO and FDA approved for food applications. The forms of alginate used in the food industry are alginic acid, sodium
alginate, potassium alginate, ammonium alginate, calcium alginate and propylene
glycol alginate. These are labeled E400–E405, respectively Featherstone (2015).
Alginates in food industry allow storage of food in cans, jars, hard gels, etc.
for longer periods while retaining or even improving the texture and consistency.
In modifying the texture, retaining moisture and improving the texture of foods,
alginate serves the role of extending food shelf life and preserving the organoleptic
properties over the food shelf life period. This has the economic and environmental
impact of reducing food waste and serving as an alternative to more energy-intensive
preservation methods such as freeze drying or freezing. Foods such as vegetables,
fruits, cheese, seafood and meat can be stored at room temperature when preserved
with alginate in methods such as canning and sealing.
The use of alginate can also be used to reduce the amount of other components
needed due to its superior viscosity enhancing and gelling property. For example,
where 5% starch is used as a thickener, about 4% of the starch can be replaced
with 1% low viscosity sodium alginate with calcium salt. This allows processing
such as improved heat transfer during heat sterilization and mixing, unlike starch
which is more sensitive to heat. The sodium alginate then reacts with the calcium
salt over time after processing to achieve the desired viscosity in the sealed food. The
viscosity difference can be up 10x Featherstone (2015). So with sodium alginate, you
can process the food at lower viscosity for easy mixing and heat transfer and then
package and seal while the sodium alginate in the presence of calcium salt continues
to increase in viscosity over a period of several hours or days.
Sodium alginate is the alginic salt which is soluble in water and is used in the food
industry for its viscosity-enhancing property. It also forms a non-thermoreversible
stable gel at room temperature on addition of calcium salt such as calcium chloride
or other polyvalent metal ions. This property makes it useful as a thickener, gelling
agent and stabilizer in the food industry. Polypropylene glycol alginate is also used
in the food industry as an emulsion stabilizer and stabilizer.
Even better than biodegradable packaging is edible packaging in the form of
films or coatings. Being indigestible edible polysaccharide alginate packaging can
contribute to the fiber intake. Alginate can serve as a sacrificial moisture agent,
whereby the moisture which would otherwise evaporate from the food evaporates
from the alginate coating instead such that the food retains its moisture content.
Alginate is used to produce edible films with thickness no more than 0.3 mm which
can be eaten with the food or easily removed. This packaging is to be as safe as the
food itself and should not alter the organoleptic properties of the food. Methods for
producing alginate films include solvent casting and extrusion (Olatunji and Olsson