Glycine (CAS 56-40-6) is the simplest amino acid — and one of the most versatile in food and nutrition. It serves as a sweetener enhancer, a buffering agent, a nutritional supplement and an amino acid in food and beverage products. This guide covers how glycine is used in food and nutrition, the grades available, and what buyers should specify.
1. Glycine in Food: The Many Roles
Glycine (NH2-CH2-COOH) is a naturally occurring, sweet-tasting amino acid (about 0.7x the sweetness of sucrose). In food it performs several functions:
- Sweetener enhancer: improves and rounds out sweetness in beverages, confectionery and low-calorie products.
- Buffering agent: stabilizes pH in food systems.
- Flavor modifier: softens salty/umami profiles and masks off-notes.
- Preservative aid: used in some seafood and meat applications for its mild antimicrobial effect.
- Nutritional supplement: an amino acid used in sports nutrition and health products.
2. Grades and Specifications
| Grade | Typical purity | Use |
|---|---|---|
| Food grade | 99%+ | Food, beverage, supplements |
| Pharmaceutical grade | 99.5%+ | Pharma formulations, IV solutions |
| Technical grade | 98-99% | Industrial, metal complexing, chemical use |
For food use, verify the COA shows purity, heavy metals (As, Pb, Hg) and chloride/sulfate within limits.
3. Food-Grade Requirements
- Meets food-additive specifications (e.g. FCC / JP / EP as applicable).
- Low heavy metals and chloride.
- White crystalline powder, no foreign odor.
- Certificate of Analysis with measured values per batch.
4. Storage and Handling
- Store dry, sealed, cool; glycine is stable and non-hygroscopic under normal conditions.
- Food-grade handling: follow food-safety practices; avoid contamination.
- Typical shelf life: 24-36 months.
Glycine Grades and Specifications
| Grade | Standard | Typical use |
|---|---|---|
| Food grade | FCC / food-additive monograph | Flavour, buffering, supplements |
| Pharmaceutical grade | USP / EP | API and excipient uses |
| Feed grade | Feed specification | Pet-food and animal nutrition |
| Technical grade | Supplier specification | Industrial buffering and synthesis |
| Property | Typical value |
|---|---|
| Formula / MW | C2H5NO2 / 75.07 g/mol |
| CAS number | 56-40-6 |
| Appearance | White crystalline powder |
| Assay | Typically 98.5–101.5% (dried basis), grade-dependent |
| Taste | Slightly sweet |
| Solubility | Readily soluble in water |
Glycine vs Other Food Amino Acids
| Amino acid | Role in food |
|---|---|
| Glycine | Sweetness, buffering, flavour, supplement and pet-food use |
| L-Glutamic acid / MSG | Umami flavour |
| L-Lysine | Nutritional fortification and feed |
| L-Cysteine | Dough conditioning and flavour precursors |
Glycine in Beverages, Supplements and Pet Food
- Beverages and supplements. Used for its sweet taste, as a buffer, and as a component of sports and wellness formulations.
- Pet food and animal nutrition. Added for palatability and as a nutrient; a common use of feed-grade glycine.
- Buffering. Glycine helps control pH and flavour in a range of food systems.
5. FAQ
Is glycine safe in food?
Yes — glycine is an approved food additive and a natural amino acid, safe at the levels used in food and beverage products.
Why is glycine sweet?
Glycine has an intrinsic sweet taste (about 0.7x sucrose), which is why it is used as a sweetener enhancer and flavor modifier.
What is the difference between food and pharma grade glycine?
Pharma grade has stricter purity and impurity limits for pharmaceutical use; food grade meets food-additive specifications.
Can glycine be used in sports nutrition?
Yes — glycine is used in amino-acid blends and sports supplements for its role in protein and collagen synthesis.
6. References and Further Reading
- Food additive specifications for glycine (FCC/JP/EP)
- Industry literature on amino acids in food and nutrition
This article is published for industrial and technical reference by PolyblueChem. Verify against the supplier’s COA and applicable standards.
PolyblueChem supplies glycine (CAS 56-40-6) in food, pharmaceutical and technical grades with COA and MSDS. See our glycine guide. Contact us for specifications and quotations.