Dynamic changes and interaction between different aroma types during low-temperature roasting of bud green tea

Area of Science:

• Food Science
• Sensory Analysis
• Analytical Chemistry

Background:

• Roasting is crucial for Wuyi rock tea aroma, but its effect on bud green tea (BGT) is under-researched.
• Understanding roasting's impact on BGT aroma is vital for tea processing optimization.

Purpose of the Study:

• To comprehensively analyze aroma perception and volatile compound changes during low-temperature roasting of BGT.
• To identify key aroma compounds contributing to the characteristic chestnut-like aroma in roasted BGT.

Main Methods:

• Quantitative Descriptive Analysis (QDA) for aroma perception changes.
• Headspace Solid-Phase Microextraction-Gas Chromatography-Mass Spectrometry (HS-SPME-GC-MS) for volatile compound identification.
• Monomolecular olfactory analysis to simulate aroma interactions.

Main Results:

• BGT aroma perception shifted from fresh to chestnut-like after roasting (105°C, 90 minutes).
• 72 out of 313 identified volatile compounds significantly differed, including floral (linalool, ionone) and caramel-like (pyrazines, furfural) compounds.
• Fresh and sweet aromas enhanced each other at low concentrations, while sweet and chestnut aromas showed mutual enhancement across all concentrations.

Conclusions:

• Low-temperature roasting significantly alters BGT aroma profile by generating specific volatile compounds.
• Key floral and caramel-like compounds are critical for the development of the desirable chestnut-like aroma in roasted BGT.
• Aroma compound interactions play a significant role in the overall sensory perception of roasted BGT.