Decrease in rice allergenic proteins of polished rice grains by incubating with a miso solution

Area of Science:

• Food Science and Technology
• Allergen Research
• Biochemistry

Background:

• Rice is a staple food, but rice allergens can cause adverse reactions in sensitive individuals.
• Developing methods to reduce allergenicity in rice is crucial for food safety and public health.

Purpose of the Study:

• To investigate the impact of miso on the reduction of allergenic proteins present in rice seeds.
• To determine the efficacy of miso, particularly soybean-koji miso, in degrading specific rice allergens.

Main Methods:

• Polished rice grains were incubated with a 10% miso solution at 37°C for 30-120 minutes.
• Comparison groups included heat-treated miso and 1% NaCl solution.
• Protein analysis involved SDS-PAGE, immunoblotting, and densitometry to quantify soluble and insoluble proteins, including specific allergens.

Main Results:

• Incubation with miso solution, especially soybean-koji miso, significantly decreased the amount of soluble proteins extracted from rice.
• Specific allergens, including a 26 kDa globulin and 14-16 kDa proteins, were reduced by 15-60% after miso treatment.
• No significant changes were observed in the content of major insoluble rice proteins.

Conclusions:

• Miso, particularly soybean-koji miso, demonstrates a potent ability to reduce key allergenic proteins in rice.
• This enzymatic activity of miso offers a promising natural approach for developing hypoallergenic rice-based food products.