Glucono Delta Lactone, Gluconolactone, Delta-gluconolactone, D-Glucono Lactone, GDL, E575, 90-80-2

Glucono Delta Lactone, Gluconolactone, Delta-gluconolactone, D-Glucono Lactone, GDL, E575, 90-80-2

Glucono Delta-Lactone (GDL) 

1. Identification and General Information

GDL is a lactone derivative of D-gluconic acid and is functionally related to D-gluconic acid. It is designated as E575 as a food additive and is a naturally occurring compound.

2. Physical and Chemical Properties

GDL is freely soluble in water and undergoes spontaneous hydrolysis to form gluconic acid, which results in a homogeneous and gradual drop in pH. It is stable when stored dry at room temperature; once dissolved in water, it converts to gluconic acid over time.

3. Chemical Structure and Reactivity

GDL is a gluconolactone and an aldono-1,5-lactone. Its molecular structure contains a lactone ring. The hydrolysis reaction in water is as follows:

text

C6H10O6 (GDL) + H2O → C6H12O7 (Gluconic Acid)

Hydrolysis Characteristics:

• Upon dissolution in water, it hydrolyzes spontaneously and slowly to gluconic acid.

• This property provides controlled and delayed acidification; unlike other food acids (such as citric acid), it does not cause an immediate drop in pH.

• Hydrolysis rate is temperature-dependent; it accelerates at higher temperatures.

• The resulting gluconic acid exhibits chelating (complex-forming) properties.

Stability:

• Chemically stable under normal temperatures and pressures.

• Incompatible with strong oxidizing agents and strong bases; keep away from these substances.

• Stable for 6 months under recommended storage conditions.

4. Production Method

GDL is commercially produced via the oxidation of glucose. The traditional production process involves the following steps:

1. Gluconic Acid Production: Gluconic acid is obtained from glucose. Several methods exist for this process:

   • Microbiological oxidation (Aspergillus niger fermentation)

   • Electrolytic oxidation

   • Chemical oxidation with hypochlorous acid

2. Lactonization: Water is removed from the obtained gluconic acid solution under appropriate conditions (temperature, catalyst, vacuum) to allow lactone ring formation and crystallization of GDL.

Alternatively, the oxidation of D-glucose with bromine water is also a commercial production method.

5. Areas of Application

5.1. Food Industry

GDL is a versatile food additive (E575) used for the following functions:

Specific Applications:

• Tofu Production: GDL is one of the most common coagulants used to curdle soy protein. It provides slow and controlled coagulation, allowing the production of smooth and soft textured tofu.

• Cheese Production: GDL is used as an acidogen in cheese making. Since it acidifies gradually, it helps form a homogeneous cheese texture.

• Meat Products: Used in meat products like bacon and fermented sausages for pH control and flavor development. It also has a preservative effect on freshness in seafood such as fresh fish and shrimp.

• Dough Leavening: GDL provides a slow but steady leavening effect when combined with sodium bicarbonate. Due to the slow hydrolysis of GDL, the leavening process continues in a controlled manner while the dough rests.

5.2. Cosmetics and Personal Care

• Used as a natural exfoliant and moisturizer in skincare products.

• Helps regulate skin pH balance due to its mildly acidic nature.

5.3. Other Industrial Applications

• Cleaning Products: As a chelating agent in powdered detergent production.

• Mining and Construction: Used to bind metal ions due to its chelating properties.

• Pharmaceutical: As an excipient.

6. Quality Specifications

The following specifications are based on European Commission Regulation (EU) No 231/2012 and FCC (Food Chemicals Codex) standards:

7. Safety Information

7.1. Toxicity and Regulatory Status

GDL is designated as GRAS by the U.S. Food and Drug Administration (FDA) and is permitted for unlimited use in foods as a curing/pickling agent, leavening agent, sequestrant, or pH control agent. It is harmless to human health and biodegradable.

7.2. Safety Precautions

• Avoid inhalation of dust.

• Avoid contact with eyes, skin, or clothing.

• Use appropriate personal protective equipment.

• Do not eat, drink, or smoke during use.

7.3. First Aid Measures

7.4. Fire Fighting

GDL is non-flammable. In case of fire, use water spray, foam, dry chemical, or CO2. Combustion products may include carbon oxides.

8. Storage and Handling

GDL should be protected from moisture and stored in tightly sealed containers. No special hazard classification exists for transport.

9. Packaging and Commercial Forms

GDL is commercially available in the following standard packaging:

• 25 kg Kraft bag

• 50 kg Fiber drum

• 500 kg or 1000 kg Bulk bag (Big Bag)

• Available in Food Grade, USP Grade, or FCC Grade purity.

10. Environmental Information

• Biodegradable.

• Non-toxic to aquatic organisms.

• Not persistent in the environment; hydrolyzes and degrades naturally.

11. Regulatory References

12. Contact and Technical Support

This technical data sheet is intended for general informational purposes regarding Glucono Delta-Lactone (GDL). For specific applications, formulation support, and current specifications, please contact your supplier.

Glucono Delta-Lactone (GDL) - Industry Application Guide

1. Alternative Names and Trade Names

In addition to the formal chemical name Glucono Delta-Lactone, it is known by various synonyms and trade names in different industries. The table below summarizes these for easy reference:

2. Application Methods and Formulation Guide

GDL's core value lies in its slow hydrolysis property, which provides gradual acidification rather than an immediate pH shock. Below is a quick-reference guide for practical applications, including typical usage rates and critical tips.

3. Formulation Recommendations and Tips

Tofu Production (Detailed Blend)

• Pure GDL Recipe: Produces a very soft, pudding-like, slightly sour tofu.

• Recommendation: Blend GDL with Calcium Sulfate.

  • Ratio: 40% GDL / 60% Calcium Sulfate.

  • Benefit: Improves yield, creates a firmer yet tender texture, and neutralizes the sour taste.

Meat Curing (Nitrite Reduction Strategy)

• GDL lowers pH slowly, which enhances the conversion of nitrite to nitric oxide (responsible for pink cured color).

• Application: When using GDL, the residual nitrite level in the final product can often be reduced by 10-20% while maintaining the same color intensity.

Baking (Shelf Life Extension)

• Unlike instant baking powder, GDL batter can be held 15-30 minutes before baking without significant loss of leavening power. This is crucial for industrial bakeries with long processing lines.

4. Alternatives and Substitutes

Depending on the specific function required, GDL can be substituted with the following materials. The choice depends on whether you need the slow acid release or just the final pH/acidity.

5. Quick Reference: Other Names in English

For international procurement and regulatory documentation, the following English identifiers are standard:

• Chemical Name: D-Glucono-1,5-lactone

• INCI Name (Cosmetics): Gluconolactone

• INS Number (Codex Alimentarius): 575

• EC Number: 202-016-5

• CAS Number: 90-80-2