Preguntas frecuentes

1. Fermentation

Uses the same bacterial strain (Sphingomonas elodea). Fermentation parameters may be finely tuned to slightly favor the natural biosynthesis of acylated polymer.

The fermentation process is similar, aiming for high yield. The level of acylation is not a primary target at this stage.

Fermentation provides the base polymer. The decisive step determining acyl content occurs after fermentation.

2. Extraction & Conversion

Core: Gentle treatment to preserve acyl groups.
1. Pasteurization: Immediate heating of the broth to inactivate cells and enzymes, preventing degradation.
2. Direct Alcohol Precipitation: The broth is promptly mixed with alcohol (isopropanol/ethanol) to precipitate the polysaccharide. This step avoids exposing the polymer to conditions that promote acyl hydrolysis, such as high temperature and high pH.

Core: Alkali treatment to remove acyl groups.
1. Heat Treatment: Prepares the broth for processing.
2. Key Alkali Treatment: Alkali (e.g., KOH) is added, and the mixture is held at elevated temperature (~80-90°C) and high pH (>10) for a defined period. This process hydrolyzes the acetate and glycerate esters from the polymer backbone.
3. Downstream Processing: Following de-esterification, the broth undergoes solid-liquid separation and alcohol precipitation.

This is the most fundamental distinction.
High-Acyl Path: Like "flash-freezing for freshness," it rapidly fixes the native structure.
Low-Acyl Path: A "chemical modification" process that alters the molecular structure, fundamentally changing its gelling properties (from thermo-reversible/elastic to thermo-irreversible/brittle).

3. Purification

The alcohol-precipitated gum is washed with alcohol-water mixtures to remove impurities, pigments, and salts. As it hasn't undergone harsh treatment, the impurity profile differs, requiring optimized washing conditions.

The precipitated gum is similarly washed. Due to the alkali treatment, it may contain more soluble salts, necessitating thorough washing.

The goal is the same: obtain high-purity polysaccharide. Washing formulations are adjusted based on the upstream process.

4. Drying & Standardization

Drying uses gentle methods (e.g., spray drying) to avoid excessive heat that could cause residual acyl loss. Standardization primarily adjusts gel strength and particle size.

Drying methods are similar. Standardization, besides gel strength, must precisely control the product's ionic (K⁺/Ca²⁺) responsiveness.

Drying must protect product functionality. Standardization focuses differ: High-acyl focuses on texture, low-acyl on the stability of ionic gelation behavior.