Analysis of the effect of tea on the flavor-related characteristics of eggs: combined analysis of HS-SPME-GC-MS, E-tongue and E-nose technology

茶叶蛋 (Tea-leaf eggs) are a traditional Chinese egg product, but the effects of tea type on quality-related and flavor-related characteristics remain not fully understood. This study compares tea-leaf eggs prepared with six representative teas using texture analysis, colorimetry, electronic nose (E-nose), electronic tongue (E-tongue), and headspace solid-phase microextraction gas chromatography–mass spectrometry (HS-SPME-GC-MS). Ripe Pu'er tea (RiPT) produced a deeper and more saturated color, while oolong tea (OT) and black tea (BT) showed distinct instrumental texture and taste response patterns. Tea addition was associated with increased compositional diversity and relative signal abundance of tentatively identified volatile organic compounds (VOCs) including aldehydes, ketones such as 2,3-butanedione, esters, and terpenoids. RiPT was also associated with reduced relative peak areas of compounds that are potential off-odor markers in tea-leaf eggs. This study provides preliminary instrumental insights into the potential role of tea type in modulating the quality attributes and volatile profiles of tea-leaf eggs, offering a reference basis for further investigation.