Dobro, da dodam i ja nešto onda (sad kad imam kad guglati, jer čedo spava )
Wikipedia kaže sljedeće:
Uses
Food additive
As a food additive, citric acid is used as a flavouring and preservative in food and beverages, especially soft drinks. It is denoted by E number E330. Citrate salts of various metals are used to deliver those minerals in a biologically available form in many dietary supplements. The buffering properties of citrates are used to control pH in household cleaners and pharmaceuticals.

Relation to MSG
Citric acid is often produced from corn rather than citrus fruits themselves. As a result the protein that is hydrolyzed remains on the product and potentially freeing glutamic acid from other protein present in the food.
i nastavlja :
Safety
Citric acid is recognized as safe for use in food by all major national and international food regulatory agencies. It is naturally present in almost all forms of life, and excess citric acid is readily metabolized and eliminated from the body.
Interestingly, despite its ubiquity in the body, intolerance to citric acid in the diet is known to exist. Little information is available as the condition appears to be rare, but like other types of food intolerance it is often described as a "pseudo-allergic" reaction.
Contact with dry citric acid or with concentrated solutions can result in skin and eye irritation, so protective clothing should be worn when handling these materials.
Excessive consumption is capable of eroding the tooth enamel.
Close contact to the eyes can cause a slight burning sensation, and may cause loss of sight.
Food info ima sličan tekst i pored ostalog još kaže:
Citric acid is present in large quantities in fruits, especially citrus fruits, in which it is predominant. In view of the fact that the isolation of citric acid from fruits is very expensive, it is commercially produced from sugar with the help of bacteria and yeasts.
Nešto više o glutaminskoj kiselini koja zna zaostati u drugim aditivima, pa i u limunskoj kiselini, vidjeti ovdje - E-numbers
Nije mi se dalo dalje bunarati, a ni tema nije o limunskoj kiselini. Toliko. Sori na podužem postu.