Glucono Delta-lactone (GDL):  (commonly found in honey, fruit juices and wine)
is a naturally occurring food additive used as a sequestrant, an acidifier, or a curing, pickling, or leavening agent. It is a cyclic ester of D-gluconic acid with chemical formula C₆H₁₀O₆ and CAS number 90-80-2. Pure GDL is a white odorless crystalline powder.
Glucono-delta-lactone, upon addition to water readily forms an equilibrium mixture of the lactone and gluconic acid.
GDL is commonly found in honey, fruit juices, and wine. Being acidic, it adds a tangy taste to foods, though it has roughly a third of the sourness of citric acid. It is metabolized to glucose; one gram of GDL is equivalent to one gram of sugar.

Sodium Benzoate (E211):  (found naturally in cranberries, prunes, plums, cinnamon, ripe cloves, and apples)
also called benzoate of soda, has chemical formula C₆H₅COONa. It is the sodium salt of benzoic acid and exists in this form when dissolved in water. It can be produced by reacting sodium hydroxide with benzoic acid.
As a food additive it is used as a preservative, effectively killing most yeasts, bacteria and fungi. Sodium benzoate is effective only in acidic conditions (pH < 3.6) making its use most prevalent in foods such as preserves, salad dressings (vinegar), carbonated drinks (carbon dioxide), jams (citric acid), fruit juices (citric acid), and chinese food sauces (soy, mustard, and duck). It is also found in alcohol-based mouthwash. More recently, sodium benzoate has become apparent in many soft drinks, including Sprite, Sunkist and Dr Pepper. It can be identified in soft drinks by 'sodium benzoate' or E211.
It is found naturally in cranberries, prunes, greengage plums, cinnamon, ripe cloves, and apples. Concentration as a preservative is limited by the FDA in the U.S. to 0.1% by weight though organically grown cranberries and prunes can conceivably contain levels exceeding this limit. Some believe the limit is 0.1% because larger amounts are poisonous.  However, the International Programme on Chemical Safety found no adverse effects in humans at doses of 647-825 mg/kg of body weight per day.^[2-3]

Calcium Gluconate: (a soluble calcium salt)
Is a soluble calcium salt. It is a traditional food preservative, calcium supplement, and used intravenously as an anti-toxin for black widow spider bites! It is also used as a topical gel to neutralize hydrofluoric acid burns.