How To Enhance Purity In Gelatin Production Process

The Gelatin Filtration Process

The filtration process in gelatin production is a core component in ensuring product transparency, purity, and microbial safety. It primarily includes physical screening, adsorption filtration, membrane separation, and matching cleaning technologies. The selection of filtration processes varies significantly depending on raw material characteristics and product grades (e.g., industrial-grade, food-grade, pharmaceutical-grade). High-quality gelatin is typically used in the pharmaceutical industry, while lower-quality gelatin is used in the food or industrial sectors. Focusing on the filtration process can enhance purity, thereby increasing its market value.

What Are the Steps in the Gelatin Filtration Process?

Primary Filtration (Coarse Filtration)

• Equipment Selection: Self-Cleaning Filter + Bag Filter.
• Filtration Purpose: Self-cleaning filters are generally used for coarse gelatin liquid filtration after acid washing/alkali washing, removing solid impurities larger than 180 μm (such as pig skin fat fragments and bone fragments) and collagen protein clumps that have not been fully decomposed after enzymatic hydrolysis. The liquid is then passed through a bag filter to remove larger particles and suspended solids (such as bone debris and skin flakes), preparing it for subsequent fine filtration.
• Gelatin Product Grade: Industrial Grade/Food Grade

Precision Filtration (Fine Filtration)

• Equipment Selection: Horizontal Plate D.E Filters(Diatomaceous Earth Filter) + Stainless Steel Plate and Frame Filter
• Filtration Purpose: Precision filtration primarily targets microscopic impurities and colloidal particles in the gelatin solution to enhance gelatin transparency. The combination of diatomaceous earth filter and Stainless Steel Plate and Frame Filter is an efficient and cost-effective filtration solution in gelatin production, particularly suitable for food-grade or pharmaceutical-grade gelatin with strict transparency requirements. This combination achieves the dual objectives of coarse filtration for decolorization + fine filtration for purification through graded filtration, with the diatomaceous earth filter achieving a precision of 2-5 μm. Using filter paper plates of different specifications, the precision of the stainless steel plate-frame fine filter can reach 0.22-2 μm.
• Gelatin product grades: Pharmaceutical capsule gelatin / Food-grade gelatin / Photographic gelatin

(For specific process details, please consult us)

Membrane filtration

• Equipment selection: membrane filtration + ion exchange
• Filtration purpose: Membrane filtration + ion exchange is the final purification stage in gelatin production, primarily used to produce ultra-high-purity pharmaceutical-grade (especially injectable-grade) gelatin. This combined technology employs both physical retention and chemical adsorption to deeply remove pyrogens, endotoxins, heavy metal ions, and small-molecule impurities, making it the most efficient gelatin filtration purification solution currently available.
• Gelatin products: High-purity pharmaceutical-grade gelatin / Injectable-grade gelatin

Bag Filter

Diatomaceous Earth Filter

Stainless Steel Plate and Frame Filter

What equipment is used in gelatin filtration?

• Self-cleaning filter: Used to remove large particles, reducing filtration pressure for subsequent stages,
• Bag filter: Used to remove particles larger than 10 μm, producing industrial-grade/food-grade gelatin products. Advantages include low cost and ease of operation; disadvantages include the need for frequent filter bag replacement,
• Cotton cake filter press: Utilizing cotton cake filter press filtration, gelatin attains a transmittance exceeding 500mm – demonstrating significant superiority over bag filter in meeting pharmaceutical capsules' stringent clarity requirements. However, this process incurs elevated manual maintenance costs and presents constraints in operational efficiency and production continuity.
• Diatomaceous Earth Filter + Stainless Steel Plate and Frame Filter: Suitable for food-grade or pharmaceutical-grade gelatin with strict transparency requirements, equipped with CIP/SIP cleaning pipelines, high automation level, suitable for large-scale continuous production.
• Membrane filtration: Retains protein colloids and microorganisms (0.1 – 0.2 μm).
• Ion exchange: adsorbs heavy metal ions (Pb²⁺, Cd²⁺) and anions (SO₄²⁻, Cl⁻), reducing conductivity.