| Description |
Delta-Gluconolactone (GDL) is a lactone of the D-gluconate. It is a natural constituent of many foods. It can be found in honey, fruit juices, wine and many-fermented products1-3. It is used as a food additive with the E number E575 used as a sequestrant, an acidifier (it lower the pH and also help preserve the food from deterioration by enzymes and organisms), or a curing, pickling, or leavening agent. GDL has been marketed for use in feta cheese. GDL is neutral, but hydrolyses in water to gluconic acid that is acidic, adding a tangy taste to foods, though it has roughly a third of the sourness of citric acid. It can be used as nutritional supplement in beverage such as in Instant Drinks, Syrups, RTD Tea and Coffee, Sports and Energy Drinks, Waters. |
| Description |
Glucono delta-lactone (C6H10O6), molecular weight 178.14, is an inner ester of gluconic acid. Commonly named gluconolactone, other synonyms include D-gluconic acid delta-lactone, D-glucono- 1, 5-lactone, and D-delta-gluconolactone. Some of its earliest uses as a food ingredient were as a flavoring (e.g., sherbets) and to reduce fat absorption in doughnuts and cones. Glucono deltalactone tastes sweet initially and has a slightly acid-aftertaste. The unpublished GRAS uses of glucono delta-lactone are as a buffer or neutralizing agent, an acidulant, and a leavening agent. It may also be used at a level up to 8 oz/100 lb of product as an accelerator of color fixing in comminuted meat or meat food products. A survey of food processors has shown that glucono delta-lactone is added to foods in several food categories for pH control, leavening, and curing.
Glucono delta-lactone is prepared commercially by the oxidation of glucose with bromine water. It is available commercially as a white, crystalline powder that is soluble in water (59 g/100 mL), slightly soluble in alcohol (1 g/100 g), and insoluble in ether. It decomposes at about 153°F.
In cold water, glucono delta-lactone hydrolyzes slowly to an equilibrium mixture of gluconic acid (55-60%) and its delta- and gamma-lactones (40-45%). The kinetics of the hydrolysis indicates that little gamma-lactone would be produced prior to establishing the delta-lactone- gluconic acid equilibrium under their test conditions, 0.05 M solution in 0.60 M acetate buffer (pH 4.63). Within 2 h, the pH of a freshly prepared 1% aqueous solution decreases from about 3.6 to 2.5. As the acidulant component of a leavening formulation, glucono delta-lactone yields gluconic acid at an accelerated rate as the temperature or concentration is increased during processing and baking operations. The stability of glucono delta-lactone in dry bakery mixes may be increased and the quality of the final baked product improved by coating the dry glucono delta-lactone with calcium stearate or vegetable oil.
The use of glucono delta-lactone with nitrites in processed meats has bacteriostatic and color stabilizing effects that are favorably enhanced by the mild acidity imparted by gluconic acid. A low pH also increases water-binding capacity and emulsifying qualities of meat protein. The predictable release of gluconic acid from glucono delta-lactone has been employed successfully for the coagulation of milk in cheese production, particularly cottage cheese. |
| Chemical Properties |
Powder |
| Uses |
Geogard(R)Ultra is a synergistic blend of gluconolactone and sodium benzoate. This blend provides broad spectrum protection against product spoilage in a variety of personal care formulations. Product Data Sheet |
| Uses |
A lactone (cyclic ester) of D-gluconic acid used as a used as a sequestrant, an acidifier, or a curing, pickling, or leavening agent. |
| Uses |
D-glucono-1,5-lactone is the lactone derivative of D-gluconic acid. D-glucono-1,5-lactone is widely used as a food additive to achieve a curing, pickling or leavening effect. |
| Uses |
a product of the oxidation of glucose by glucose oxidase |
| Uses |
Component of many cleaning cmpds because of the sequestering ability of the gluconate radical which remains active in alk solutions; in the dairy industry to prevent milkstone; in breweries to prevent beerstone; as latent acid catalyst for acid colloid resins, particularly in textile printing; as a coagulant for tofu. |
| Uses |
gluconolactone is used in cosmetics for its anti-acne properties. It can also help improve skin hydration given its water-binding ability. In addition, formulators may select gluconolactone for its action as a product stabilizer (chelating agent). Some studies indicate potential free-radical scavenging capacities as well. These properties would make it particularly relevant for use in making anti-aging, moisturizing, and possibly sun care products. |
| Uses |
(GDL) An acidulant. It hydrolyzes to form gluconic acid in water solution and thereby creates the desired pH. The rate of acid formation is affected by temperature, concentration, and the pH of the solution. It has low acid release at room temperature and accelerated conversion into gluconic acid at high temperatures. It is readily soluble with a solubility of 59 g in 100 ml of water at 20°C. It functions as a leavening agent, acidulant, curing and pickling agent, and pH control agent. It is comparatively less tart/sour than other food acids. It is used in baked goods, fish products, desserts, and dressings. |
| Safety Profile |
Mutation data reported. When heated to decomposition it emits acrid smoke and irritating fumes. |
| Purification Methods |
Crystallise Dglucono-lactone from ethylene glycol monomethyl ether and dry for 1hour at 110o. It can be freed from other sugars via a column of Celite and charcoal (750g of each, 90 x 7.5cm) which is washed with 0.01N formic acid until the pH of the wash is equal to that of the entering acid. The lactone is applied in H2O and eluted with 0.01N formic acid (7L), then eluted with 7.5% EtOH/0.01N formic acid (8L), then 15% EtOH/0.01N formic acid (8L) which removes pentose and isomaltose (the optical rotation of the eluates are used for sugar detection) and finally elution with aqueous formic acid provides glucolactone which is obtained by evaporating or freeze drying. Its solubility in H2O is 60% and 1% in EtOH. A solution in H2O is slightly acidic, and the lactone dissolves in an equivalent of aqueous NaOH to form sodium D-gluconate [527-07-1] M 218.1, m 2002 0 6o(dec), [ ] D 25 +12o (c 10, H2O), pK2 5 3.6. [cf p 553, Smith & Whelan Biochemical Preparations 10 127 1963, Beilstein 3 IV 1255.] |
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