Rice Flour Pretreatment Using Air Classification and Moisture Conditioning

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Solution Overview

Problem

Current rice flour manufacturing methods require lengthy water-washing and soaking steps, leading to high drainage treatment costs and inefficient moisture distribution, resulting in coarse flour and increased energy consumption.

Innovation Solution

A pretreatment method involving a moisture homogenizing step to adjust the moisture content of milled rice using low-humidity air, followed by a moisture conditioning step to add water and soften the aleuronic layer, allowing for bran removal and subsequent easy crushing of rice grains into fine flour without the need for extensive water use or drainage treatment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If water-washing and soaking steps are used to homogenize moisture and soften rice grains, then rice flour quality is improved, but drainage treatment costs and environmental pollution increase

Engineering Contradiction:
Improverice flour qualityVSAvoiddrainage pollution
Core Design Contradiction:
Manufacturing precisionVSObject-generated harmful factors

Solution Approach 1:

The invention extracts and eliminates the water-washing and soaking steps from the traditional rice flour manufacturing process. By using air classification technology, the method removes the need for water-based pretreatment while maintaining rice grain integrity and achieving uniform moisture distribution without generating drainage pollution.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention replaces the water-based mechanical soaking process with an air-based classification system. Air is used to separate and sort rice grains based on their moisture content and density, achieving homogenization without water contact, thereby eliminating drainage treatment requirements.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Stability of the object's composition

If long soaking time is used to achieve uniform moisture distribution, then rice grain softness is improved, but production time and energy consumption increase

Engineering Contradiction:
Improvemoisture distribution uniformityVSAvoidproduction time
Core Design Contradiction:
Stability of the object's compositionVSLoss of time

Solution Approach 1:

The invention performs moisture homogenization as a preliminary action before milling, using air classification to pre-sort rice grains by moisture content. This preliminary sorting achieves uniform moisture distribution instantaneously, eliminating the need for prolonged soaking periods and reducing overall production time.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The invention uses pneumatic (air-based) classification technology to separate and redistribute rice grains according to their moisture content. Air currents lift and sort grains, achieving rapid moisture homogenization without water immersion, thereby dramatically reducing the time required compared to traditional soaking methods.

Inventive Principle:
Principle #29Pneumatics and hydraulics

3Manufacturing precision

If traditional water-grinding method is used to mill rice, then fine rice flour is produced, but high energy consumption and coarse flour particles result from insufficient softening

Engineering Contradiction:
Improveparticle size finenessVSAvoidmilling energy consumption
Core Design Contradiction:
Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

The invention changes the physical state and distribution parameters of rice grains before milling by using air classification to achieve uniform moisture content. This parameter optimization ensures that all grains are in a similar state of readiness for milling, reducing the energy required to achieve fine particle sizes and minimizing coarse flour production.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This method reduces the hardness of rice grains, enabling finer milling with lower energy requirements and eliminating the need for costly drainage treatment, while maintaining flour quality and preventing damaged starch.

Implementation Method 1

supplying air of low humidity to milled rice having a moisture content of 13.0∼16.0% (w. b.%) to adjust the moisture content in the milled rice to 11.0 ∼13.0% (w. b.%)

Methodology Applied
Scientific EffectEvaporation: Evaporation

Implementation Method 2

adding water to the rice grains had the moisture homogenizing step passed through, until moisture content in each of the rice grains of rice reaches 20. 0∼45.0% (w. b. %), and facilitating water absorption into the core of each of the grains of the milled rice

Methodology Applied
Scientific EffectAbsorption: Absorption (physical)

Implementation Method 3

facilitating water absorption into the core of each of the grains of the milled rice

Methodology Applied
Scientific EffectOsmosis: Osmosis

Implementation Method 4

removing both the bran and the softened aleuronic layer by the friction of rice grains relative to one another

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP2762232B1Pre-milling treatment method for producing rice flour and device therefor
Publication Date: 2020.01.01 SATAKE CORP
  • EP2762232B1 patent drawingFigure 1
  • EP2762232B1 patent drawingFigure 2

AI summary

There are provided a flour milling pretreatment method for manufacture of rice flour and its apparatus for drastically reducing hardness of rice without having need of water-washing and soaking steps. The method comprises a moisture homogenizing step for supplying low-humidity air to milled rice having a moisture content of 13.0∼16.0% (w. b.%), to adjust the moisture content in the milled rice to 11.0 ∼13.0% (w. b.%), thereby homogenizing the moisture and a moisture conditioning step for adding water to the rice grains had the moisture homogenizing step passed through until the moisture content in each of the rice grains of rice reaches 20. 0∼45.0% (w. b. %), and facilitating water absorption into the core of each of the grains of the milled rice after the water addition.