Investigation about the potential of citron, sweet lemon, and sweet orange peels as herbal tea

This study investigated the sensorial quality, chemical composition, and bioactive potential of herbal teas made from the peels of sweet lemon (Citrus limetta Risso), sweet orange (Citrus sinensis), and citron (Citrus maxima (Burm.) Merr) using freeze-drying, hot-air drying, and microwave drying. Sensory evaluation showed that teas from microwave-dried peels were most preferred, with microwave-dried sweet orange peel tea receiving the highest acceptability score (6.78/9). In contrast, freeze-dried sweet orange peel tea had the highest total phenolic content (843.40 mg GAE/L), while the microwave-dried version had the lowest (279.20 mg GAE/L). Hesperidin, protocatechuic acid, and chlorogenic acid were dominant in different citrus teas. Key volatiles included linalool in sweet lemon, naphthalene in sweet orange, and 2-furanmethanol derivative in citron. Sweet lemon peel tea had the highest antioxidant activity (0.90 mmol TE/L) and gastric bioaccessibility (0.22 mmol TE/L). Simulated digestion reduced most bioactive compounds; however, hesperidin, syringic acid, chlorogenic acid, protocatechuic acid, and luteolin-7-glycoside remained detectable depending on the tea type. Pesticide residues were found only in microwave-dried sweet orange peel tea, but remained below legal limits. While microwave drying enhanced sensory appeal, freeze-drying better preserved bioactive compounds. Overall, citrus peels show strong potential as sustainable raw materials for functional herbal teas. • Freeze-dried sweet orange peel tea had the highest phenolic content. • Sweet lemon peel tea showed best antioxidant activity before and after digestion. • Citron, sweet lemon and sweet orange teas showed distinct aroma–volatile profiles. • Lemon, orange and citron teas showed key volatiles like linalool and naphthalene. • Pesticide analysis detected 0.14 mg/kg azoxystrobin in sweet orange peel tea.