Activated Carbon for Amino Acid Purification
Food-grade powdered activated carbon for decolorizing amino acid fermentation broth — adsorbing melanoidins, Maillard pigments and odor compounds so lysine, threonine, tryptophan and other amino acids crystallize bright, pure and compliant.
The Purification Challenge
Why fermentation-derived amino acids need carbon treatment
Industrial amino acids — lysine, threonine, tryptophan, glutamic acid, phenylalanine and more — are produced by microbial fermentation of sugar or starch feedstocks. The broth accumulates melanoidins, Maillard-reaction pigments, residual proteins and odor compounds that would carry through to the crystal if left untreated. Before the amino acid is concentrated and crystallized, the clarified liquor is treated with powdered activated carbon. The carbon's mesopore network adsorbs large-molecule color bodies and aromatic off-flavor compounds that ion-exchange and membrane steps leave behind — delivering a water-white liquor and bright, high-purity crystals that meet food-additive or feed-grade specifications.
How Amino Acid Decolorization Works
From fermentation broth to purified crystals
After fermentation, the broth is separated from biomass by centrifugation and microfiltration. The clarified but still-pigmented liquor is the carbon-treatment feed.
Powdered activated carbon is dosed at 0.3–2% (w/w on solids) and mixed 20–60 minutes at 50–80°C. Mesopore-rich carbon adsorbs melanoidins, Maillard pigments and aromatic impurities.
Spent carbon is removed on filter presses, leaving a near-colorless, odor-free liquor. The purified solution is concentrated and crystallized into bright, high-purity amino acid crystals.
Where It's Used
Amino acids we supply purification carbon for
Carbon Selection
Choosing carbon by purification duty
Match the grade to your color load and purity target. Every lot ships with a batch COA — methylene blue, iodine, ash, moisture and heavy metals.
| Purification Duty | Recommended Grade | Key Spec | Form |
|---|---|---|---|
| Primary broth decolorization | Wood-based PAC, high MB | MB ≥180 mg/g | Powder |
| Deep color & odor removal | Wood-based PAC, acid-washed | Low ash, high mesopore | Powder |
| Fine polishing before crystallization | Coconut-based PAC, food-grade | Iodine ≥950, low ash | Powder |
| Mother liquor recycle | Wood-based PAC, cost-optimized | MB ≥160 mg/g | Powder |
Not sure which grade fits your amino acid and purity target? Send us a sample.
Get a Grade RecommendationProcess Design
Purer crystals at lowest carbon cost
Dose & contact time
Powdered carbon at 0.3–2% w/w on dissolved solids, mixed 20–60 minutes at 50–80°C. Higher color loads (lysine, tryptophan) need the upper range; lighter amino acids sit lower. Optimize by bench trial.
Two-stage vs single-stage
For heavily pigmented broths, two smaller carbon doses with intermediate filtration remove more color per kg than one large dose — reducing total cost and filter-cake yield loss.
High methylene blue
Melanoidins and Maillard color bodies are large molecules. A high-methylene-blue (MB ≥180 mg/g) wood-based PAC with mesopore volume adsorbs them efficiently where micropore-only carbon struggles.
Low ash & food compliance
Amino acid crystals are food or feed additives. Low-ash, acid-washed carbon avoids mineral pickup and meets FCC, GB 1886.229 and EU food-contact limits with batch traceability.
Technical Specifications
| Parameter | Wood PAC (Decolorizing) | Coconut PAC (Polishing) |
|---|---|---|
| Methylene Blue | ≥180 mg/g | — |
| Iodine Number | ≥800 mg/g | ≥950 mg/g |
| Mesh / Form | 200 mesh powder | 200 mesh powder |
| Ash Content | ≤4% | ≤3% |
| Moisture | ≤10% | ≤5% |
| Certification | FCC / HALAL / KOSHER | FCC / HALAL / KOSHER |
Field Performance
Proven across amino acid fermentation plants
Case: lysine producer cuts carbon cost and improves crystal brightness
A large-scale lysine HCl fermentation plant replaced its standard PAC with a high-methylene-blue acid-washed wood-based grade and switched from single-stage to two-stage dosing. The new protocol removed deeper color bodies the previous carbon missed, delivering noticeably brighter crystals — while reducing total carbon consumption by 25% and filter-cake product loss.
Recommended Products
These are the grades we recommend most often for amino acid decolorization. Contact us for a tailored recommendation.
Wood-Based Powdered Activated Carbon (PAC)
Primary amino acid decolorization, high methylene blue
Coconut Shell Powdered Activated Carbon (PAC)
Fine polishing before crystallization, low ash
Wood-Based Activated Carbon (Series)
Range of food-grade decolorizing grades
Amino Acid Carbon — Frequently Asked Questions
What activated carbon is best for amino acid purification?
A food-grade, high-methylene-blue (MB ≥180 mg/g) wood-based powdered activated carbon. Amino acid fermentation pigments are large molecules (melanoidins, Maillard products) that need mesopore-rich carbon for efficient adsorption. Low ash and acid-washed grades are preferred for tryptophan and phenylalanine where purity demands are highest.
How much carbon is needed per batch?
Typically 0.3–2% of dissolved solids by weight, depending on the amino acid and broth color. Lysine and tryptophan sit at the higher end; threonine and valine at the lower end. Always run a bench trial to optimize dose vs. color target.
Can one carbon grade cover multiple amino acids?
Yes. The same family of high-MB wood-based PAC works across lysine, threonine, tryptophan, glutamic acid and other fermentation amino acids. We match the specific spec (MB value, ash, acid-wash) to each amino acid's purity requirement.
Does carbon remove off-flavors and odor?
Yes. Mesopore-rich wood PAC adsorbs aromatic by-products (indoles in tryptophan, pyrazines in MSG) and Maillard odor compounds, improving the sensory profile of the finished amino acid product.
Is the carbon food-grade and certified?
Yes. Our amino acid purification carbon meets food-contact limits on heavy metals and extractable impurities, supporting FCC, GB 1886.229 (China) and EU specifications. It ships with HALAL, KOSHER and ISO 9001 documentation and a batch COA on every lot.
What is the MOQ and lead time?
MOQ is 1 ton, with free samples for bench trials. Standard lead time is 10–15 days factory-direct. Packaging: 25 kg bags or 500 kg jumbo bags, with private-label options.
Purer amino acids at lower carbon cost
Tell us the amino acid, broth color, throughput and purity target. We'll recommend the right food-grade carbon and dose, and ship a free sample for your bench trial — batch COA on every lot.
Request an Amino Acid Carbon Quote