Sodium gluconate or sodium d-gluconate, the sodium salt of gluconic acid with the European food additive number E576, is different with other gluconates that can be used as a nutrient, this ingredient is mainly used as a chelating agent and cleaner in food and industrial uses.
It is a multi-functional ingredient that can be used in a lot of fields, commonly used for its outstanding chelating property in food and industrial uses. Also used for its PH buffering and taste improvement in food.
Food grade sodium gluconate can be used as:
- A sequestrant agent by chelating undesirable metal ions.
- A PH buffer in drink.
- A taste improver for beverage by masking off-notes or reducing the bitterness/aftertaste from artificial sweeteners, soybean protein, minerals or caffeine.
- A stabilizer in meat products by increasing meat water-binding capacity and improving its firmness and sliceability. Meanwhile, sodium gluconate is a replacement of phosphates. (1)
Pharma & Nutraceutical
It can be used as an excipient as a buffer and pH adjuster in the following products (2):
- Swallowable/orally dispersible tablets
- Hard capsules
Sodium gluconate functions as a chelating and skin conditioning in cosmetic and personal care products. (3)
And usually we can find it in skin care products like face cream, soap, and toothpaste.
With good sequestering power (over EDTA, NTA and some other related compounds) to combine with di- and trivalent metal ions, such as calcium, iron, copper, aluminium to form stable chelates and take them out of water or the solution at an alkaline pH, and with little effect on temperature.
Due to this property, it is widely used in:
- Water treatment
- Bottle washing
- Corrosion inhibition
- Metal surface treatment
- Industrial cleaning
In addition, it can be used in the construction industry, as a retarding cement enhancing additive. (4)
There are five hydroxyl groups and a carboxylic acid group in the chemical structure.
A white to tan powder or granular.
Very soluble in water, sparingly soluble in ethanol.
Between 6.5 and 7.5 (10 % solution) (5)
Yes, it has been approved safe by the U.S. Food and Drug Administration (FDA) and European Food Safety Authority (EFSA), as well as the Joint FAO/WHO Expert Committee on Food Additives (JECFA).
Sodium gluconate is generally recognized as safe (GRAS) when used as a sequestrant in food. (6)
Sodium gluconate (E576) is listed in Commission Regulation (EU) No 231/2012 as an authorised food additive and categorized in “ additives other than colours and sweeteners” (7).
It is classified into “Group I” with the maximum use levels “quantum satis”, which means there is no specific limit in its uses. The following food may contain it (8):
- Dairy products
- Fats and oils and fat and oil emulsions
- Fruit and vegetables
- Cereals and cereal products
- Bakery wares
- Fish and fisheries products
- Eggs and egg products
- Table-top sweeteners
- Salts, spices, soups, sauces, salads and protein products
UK Food Standards Agency
Categorized in “Others” (9)
Food Standards Australia New Zealand
It is approved ingredient in Australia and New Zealand with the code number 576. (10)
Function Class: food additives, sequestrant, yeast food. (11)
How is it made?
Sodium gluconate can be synthesized from the reaction of gluconic acid ( produced by oxidation of D-glucose, derived from starch) and sodium hydroxide.
Is it gluten free?
Yes, it is gluten free as it does not contain wheat, rye, barley, or crossbreeds of these grains, therefore can be used for people with celiac disease.
Gluconic acid vs sodium gluconate?
Gluconic acid is the liquid, not convenient to use in some applications, and where it is combined used with sodium hydroxide, better to use sodium gluconate directly.
Now you may have a knowledge of the chelating agent – sodium gluconate (E576), from the following aspects:
- Manufacturing process
What kinds of food labels have you found this additive in? Feel free to let me know in the comments.