Comparative Study of Key Aroma Components in Rice of Different Aroma Types Using Flavor Metabolomics

Area of Science:

• Food Chemistry
• Analytical Chemistry
• Sensory Science

Background:

• Rice aroma is a critical quality attribute influenced by diverse volatile organic compounds (VOCs).
• Understanding the chemical basis of rice aroma variations is essential for quality control and product development.

Purpose of the Study:

• To analyze VOCs in different rice aroma types.
• To correlate specific aroma compounds with sensory perceptions.
• To elucidate the material basis of rice flavor differences.

Main Methods:

• Sensory evaluation to categorize rice aroma types.
• Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) for untargeted metabolomics.
• Gas chromatography-ion mobility spectrometry (GC-IMS) for fingerprint analysis.

Main Results:

• Rice aroma categorized into three types (sweet/popcorn, cereal/starchy, complex) based on sensory evaluation.
• HS-SPME-GC-MS identified 74 volatile compounds, with 8 key compounds differentiating aroma types.
• GC-IMS confirmed distinct aroma fingerprints and identified specific VOCs contributing to sweet and complex aromas.

Conclusions:

• Specific VOCs like (E)-2-Octenal and 2-Acetyl-1h-pyrrole are crucial for sweet rice aroma.
• Compounds such as Dodecane and 1-Octen-3-one contribute to cereal and starchy notes.
• Distinct VOC profiles confirmed by GC-IMS provide a chemical basis for rice aroma classification.