Tannic acid

Buyers must distinguish between Industrial Grade, Food Grade, and Pharmaceutical Grade (USP/EP). Key parameters include purity levels (typically 80% to 99%), moisture content (usually <7%), and heavy metal limits (Lead <2ppm, Arsenic <3ppm). For the wine and beverage industry, ensure the product meets OIV (International Organisation of Vine and Wine) standards to guarantee it does not affect the sensory profile of the end product.

Ensure the supplier provides a Certificate of Analysis (COA) for every batch. For food applications, verify FCC (Food Chemicals Codex) compliance and ISO 22000 or HACCP certifications. If exporting to the EU, the supplier must comply with REACH regulations. For pharmaceutical use, look for GMP (Good Manufacturing Practice) certification to ensure the highest level of safety and consistency.

Tannic acid is highly versatile. In the textile industry, it is used as a mordant for dyeing; in the leather industry, it acts as a tanning agent. For water treatment, it serves as a coagulant. Buyers should specify the source material (e.g., Chinese Gallnut or Tara Pods), as gallnut-derived tannic acid generally offers higher purity and better performance in high-end chemical synthesis.

Tannic acid is light-sensitive and hygroscopic. It must be stored in cool, dry, and dark conditions using air-tight containers (often fiber drums with PE inner bags). The typical shelf life is 24 months; however, exposure to air can cause oxidation and darkening, which may render it unsuitable for applications requiring high color stability.

Always request a pre-shipment sample (PSS) that represents the actual mass production lot. Utilize third-party inspection services like SGS or Intertek to perform random sampling at the factory before the balance payment is made. On Made-in-China.com, prioritize Audited Suppliers who have undergone on-site verification of their production capabilities.

While Tannic Acid is generally not classified as a hazardous good (Non-DG) for transport, you must ensure the supplier provides a Material Safety Data Sheet (MSDS) and a Non-Hazardous Chemical Appraisal Report for customs clearance. Ensure the packaging is moisture-proof to prevent clumping during long-term sea freight, especially when crossing high-humidity tropical zones.

Chemical prices fluctuate based on raw material harvests (Gallnut seasons). It is advisable to sign annual framework agreements to lock in prices. For new suppliers, use Secure Payment terms or a Letter of Credit (L/C). Avoid 100% upfront payments; a standard 30% deposit and 70% against the Bill of Lading (B/L) is the industry norm for established B2B relationships.

Check the HS Code (typically 320190) for specific import duties in your country. Be mindful of anti-dumping duties that some regions may impose on Chinese organic chemicals. Ensure all Export Licenses are handled by the supplier to avoid delays at the port of exit.