Cassava starch maltodextrinization/monomerization through thermopressurized aqueous phosphoric acid hydrolysis

Area of Science:

• Biotechnology
• Food Science
• Chemical Engineering

Background:

• Cassava starch is a widely available polysaccharide resource.
• Traditional starch hydrolysis methods often involve costly and complex desalting steps.
• Industrial fermentation requires a balanced nutrient supply for optimal growth.

Purpose of the Study:

• To establish kinetic conditions for cassava starch depolymerization using phosphoric acid.
• To evaluate the efficiency of phosphoric acid hydrolysis for producing maltodextrins and glucose syrups.
• To explore the potential of this process for industrial fermentation and high-value product generation.

Main Methods:

• Kinetic studies of cassava starch depolymerization.
• Thin-layer chromatography and high-performance liquid chromatography for analysis.
• Controlled neutralization with ammonia for nutrient generation.

Main Results:

• Optimized phosphoric acid strength and thermopressurization (142-170°C, 2.8-6.8 atm) enable efficient starch hydrolysis.
• The process avoids the need for desalting steps required by traditional catalysts.
• Neutralized hydrolysate provides essential carbon, phosphorus, and nitrogen for industrial fermentations.
• Upgraded glycosyl syrups support the production of Xanthophyllomyces dendrouchous (Phaffia rhodozyma) yeast biomass rich in astaxanthin.

Conclusions:

• Phosphoric acid pretreatment is an efficient and cost-effective technology for starch hydrolysis and upgrading.
• This method simplifies downstream processing and offers a sustainable route for producing fermentation nutrients.
• The process enables the valorization of cassava starch into food ingredients, single-cell protein, and natural pigments.