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).

FDA
Sodium alginate is generally recognized as safe (GRAS) that can be used as a thickener, stabilizer, texturizer and firming agent in (4):

Condiments and relishes
Confections and frostings
Gelatins and puddings
Hard candy
Processed fruits and fruit juices
Other food categories
EFSA
Sodium alginate (E401) is listed in Commission Regulation (EU) No 231/2012 as an authorised food additive and categorized in “ additives other than colours and sweeteners” (5).

Safety re-evaluation in 2017

EFSA conducted the safety revaluation for alginic acid and its salts of sodium, potassium, ammonium and calcium as food additives, and derived the following conclusions (6):

No safety concern and no need to establish an ADI as an additive used in food.
The usage for infants and young children should be below therapeutic dosages.
Inadequate assessment of the safety when used in “dietary foods for special medical purposes and special formulae for infants”and “dietary foods for babies and young children for special medical purposes”.
Approved uses
It is classified into “Group I” with the maximum use levels “quantum satis”, also listed separately and with alginic acid (E400), potassium alginate (E402), ammonium alginate (E403) and calcium alginate (E404). The following food may contain it (7):

Unflavoured pasteurised cream
Meat preparations
Desserts and puddings
Jam, jellies and marmalades
UK Food Standards Agency
Categorized in “Emulsifiers, stabilizers, thickeners and gelling agents” (8)

Food Standards Australia New Zealand
It is an approved ingredient in Australia and New Zealand with the code number 401. (9)

JECFA
Function Class: food additives, emulsifier, gelling agent, stabilizer, thickener. (10)


Acceptable daily intake: ADI “not specific” set in 1992. (11)

Frequently asked questions
Is it natural?
Yes, sodium alginate is a natural polysaccharide composed of two types of uronic acids.

Is it vegan?
Yes, it is vegan as the raw material used and manufacturing process without the use of animal matter or products derived from animal origin. So it can be added in the food for vegetarians.

Is sodium alginate a hydrocolloid?
Yes, as it can thicken or gel water.

What’re the benefits?
Sodium alginate is a non-digestible carbohydrate and the FDA intends to propose it in the list of dietary fibers. It has the benefits of lowering blood sugar, blood pressure, cholesterol levels and other health effects. (12)

Conclusion

Now you may have a knowledge of the thickener – sodium alginate (E401), from the following aspects:

Production process: extracted from seaweeds.
Properties: viscosity, gelling, solubility and PH.
Uses: commonly for its thickening and gelling property.
Safety
FAQs: is it natural, vegan and the benefits.