Study on the Damage Characteristics of Wheat Kernels under Continuous Compression Conditions

Area of Science:

• Agricultural Engineering
• Material Science
• Food Processing Technology

Background:

• Wheat peeling enhances flour quality but risks kernel damage.
• Continuous compression in flaking machines causes cumulative kernel damage and breakage.
• Understanding wheat kernel damage mechanics is crucial for optimizing processing.

Purpose of the Study:

• To establish and validate a continuous damage model for wheat kernels during peeling.
• To investigate the damage characteristics and critical parameters of wheat kernels under compression.
• To provide a theoretical basis for designing and optimizing wheat peeling machines.

Main Methods:

• Developed a continuous damage model integrating Hertzian contact and continuous damage theories.
• Conducted continuous compression tests on different wheat varieties (Ningmai 22, Jichun 1) and kernel sizes using a mass spectrometer.
• Validated the model by comparing theoretical predictions with experimental data to calculate critical damage parameters.

Main Results:

• Determined average maximum crushing forces and deformations for various kernel sizes and varieties.
• Calculated average elastic-plastic critical pressures and deformations, showing varietal and size-dependent differences.
• Established that kernel deformation exceeding critical values leads to crushing, with smaller kernels being more susceptible.

Conclusions:

• Wheat kernel breakage during peeling is linked to exceeding elastic-plastic critical deformation thresholds.
• Optimizing peeling machine parameters requires controlling pressure and deformation below critical values for smaller kernels.
• The study provides essential data for improving wheat peeling machine design and processing efficiency.