# Jin Xuan (Camellia sinensis)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/jin-xuan
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-31
**Evidence Score:** 2 / 10
**Category:** Tea Cultivars
**Also Known As:** Cultivar No. 12, Taiwan Tea Cultivar 12, TRES No. 12, Milk Oolong cultivar, Jin Xuan oolong, 台茶十二號, 金萱茶, Camellia sinensis var. Jin Xuan

## Overview

Jin Xuan is a Taiwanese oolong tea cultivar (TRES #12) derived from Camellia sinensis, prized for its naturally creamy, milk-like aroma produced by specific terpene alcohols including nerolidol and linalool. Its bioactive profile includes EGCG, ECG, EGC, caffeine, and L-theanine, compounds associated with [antioxidant activity](/ingredients/condition/antioxidant) and [cognitive](/ingredients/condition/cognitive) modulation in the broader green and oolong tea literature.

## Health Benefits

• No clinical evidence available - research focuses solely on agronomic traits and biochemical composition rather than health effects
• Contains standard tea polyphenols including EGCG, ECG, and EGC found in Camellia sinensis (preliminary evidence level)
• Provides caffeine and theanine typical of oolong teas (traditional use only)
• May share general [antioxidant](/ingredients/condition/antioxidant) properties of tea catechins (no cultivar-specific evidence)
• Nitrogen-fertilized variants show increased polyphenol content in agricultural studies (not tested in humans)

## Mechanism of Action

EGCG (epigallocatechin gallate) in Jin Xuan inhibits catechol-O-methyltransferase (COMT) and scavenges [reactive oxygen species](/ingredients/condition/antioxidant) via direct electron donation, reducing oxidative stress at the cellular level. L-theanine modulates alpha-wave brain activity by acting as a glutamate receptor antagonist at NMDA and AMPA receptors while also increasing GABA and [serotonin](/ingredients/condition/mood) synthesis. Caffeine competitively antagonizes adenosine A1 and A2A receptors, enhancing alertness, and its synergistic interaction with L-theanine is thought to attenuate caffeine-induced sympathetic overstimulation.

## Clinical Summary

No clinical trials have been conducted specifically on Jin Xuan as a distinct cultivar; existing research on this variety focuses entirely on agronomic performance, aroma compound profiles, and comparative catechin concentrations rather than human health outcomes. Evidence for its health effects must be extrapolated from the broader oolong and green tea literature, where randomized controlled trials involving Camellia sinensis preparations (typically 300–800 mg EGCG daily) have demonstrated modest effects on LDL oxidation, fasting glucose, and [cognitive performance](/ingredients/condition/cognitive). A 2017 meta-analysis of 11 RCTs found green tea catechin supplementation reduced [LDL cholesterol](/ingredients/condition/heart-health) by approximately 2.2 mg/dL, but these findings are not directly transferable to Jin Xuan due to variability in catechin concentration across cultivars and processing methods. The evidence for Jin Xuan-specific health benefits should be considered preliminary and largely inferential.

## Nutritional Profile

Jin Xuan (Camellia sinensis cv. TTES No. 12) is a Taiwanese oolong tea cultivar consumed primarily as a brewed beverage; nutritional contribution comes from dissolved compounds in infusion rather than whole-leaf consumption. Brewed infusion (200ml, ~2g dry leaf): Calories ~2-4 kcal, Protein ~0.1-0.2g (minimal, mostly amino acids), Carbohydrates ~0.5-1g, Fat negligible (<0.05g), Fiber negligible in liquid form. Bioactive polyphenol profile: Total catechins approximately 150-300mg per 2g dry leaf depending on oxidation level and brew parameters; EGCG (epigallocatechin gallate) ~50-120mg/2g dry leaf (primary catechin, reduced compared to green tea due to partial oxidation); ECG (epicatechin gallate) ~20-50mg/2g dry leaf; EGC (epigallocatechin) ~15-40mg/2g dry leaf; EC (epicatechin) ~10-30mg/2g dry leaf; theaflavins and thearubigins present at low-moderate levels (~20-60mg/2g) reflecting partial oxidation characteristic of oolong processing. Caffeine content: ~20-40mg per 200ml brew (moderate, lower than black tea, higher than white tea). Theanine (L-theanine): ~5-15mg per 200ml brew, a distinguishing amino acid of Camellia sinensis promoting relaxed alertness; Jin Xuan reportedly exhibits creamy/milky flavor notes associated with specific lactone and terpene alcohol compounds (linalool, nerolidol, indole) at trace sensory-relevant concentrations rather than nutritionally significant levels. Minerals in brewed tea: Fluoride ~0.1-0.3mg/200ml; Manganese ~0.2-0.5mg/200ml; Potassium ~20-40mg/200ml; Magnesium ~2-5mg/200ml; trace Zinc, Selenium, Calcium. Vitamins: Trace Vitamin C (~1-3mg/200ml, reduced by oxidation), trace Vitamin K (~0.5-2mcg/200ml). Bioavailability notes: Catechin bioavailability is moderate (~5-20% absorption); co-consumption with milk proteins may reduce polyphenol bioavailability by binding catechins; theanine bioavailability is high (~95%); caffeine bioavailability approaches ~99%. Dry leaf macronutrient composition (per 100g dry weight, not typical consumption form): Protein ~20-25g, Total Catechins ~12-20g, Carbohydrates ~60-65g, Fiber ~35-40g, Fat ~3-5g.

## Dosage & Preparation

No clinically studied dosage ranges available. Traditional preparation involves steeping tea leaves for 3 minutes at 80-100°C, but no standardized extracts or clinical dosing protocols exist. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Jin Xuan tea is generally well tolerated at typical beverage consumption levels, but its caffeine content (approximately 20–40 mg per 8 oz serving depending on oxidation and brewing) may cause [insomnia](/ingredients/condition/sleep), palpitations, or anxiety in sensitive individuals or at high doses. EGCG at supplemental doses above 800 mg/day has been associated with hepatotoxicity in isolated case reports, though this risk is negligible from standard tea consumption. Jin Xuan may interact with anticoagulants such as warfarin due to vitamin K content in tea leaves and may reduce absorption of non-heme iron when consumed alongside iron-rich meals. Pregnant individuals are advised to limit caffeine intake to under 200 mg/day per major obstetric guidelines, which applies to Jin Xuan consumption as with any caffeinated tea.

## Scientific Research

No human clinical trials, RCTs, or meta-analyses specific to Jin Xuan cultivar were identified in available sources. All existing research focuses on agronomic performance, yield optimization, and plant biochemistry rather than biomedical applications. No PMIDs are available as no clinical studies exist.

## Historical & Cultural Context

Jin Xuan lacks documented historical use in traditional medicine systems as it is a modern cultivar developed in 1980 specifically for commercial oolong tea production. It has become popular in contemporary Taiwanese and Thai tea culture for its distinctive creamy, floral, and milky flavor profile rather than medicinal purposes.

## Synergistic Combinations

Green tea extract, L-theanine, EGCG, white tea, matcha

## Frequently Asked Questions

### What makes Jin Xuan tea different from other oolong teas?

Jin Xuan (TRES #12) is a cultivar developed by the Taiwan Tea Research and Extension Station specifically for its characteristic creamy, milky aroma, which arises from elevated concentrations of terpene alcohols such as nerolidol, linalool, and indole formed during partial oxidation. Unlike heavily oxidized oolongs, Jin Xuan is typically processed at 15–30% oxidation, preserving a higher catechin content closer to green tea while retaining its distinctive floral-dairy aromatic profile. This compositional profile distinguishes it agronomically and aromatically, though not yet clinically, from other Camellia sinensis cultivars.

### Does Jin Xuan tea contain EGCG?

Yes, Jin Xuan contains EGCG (epigallocatechin gallate) along with ECG and EGC, as it is a cultivar of Camellia sinensis, the same species that produces green, white, and black teas. The exact EGCG concentration varies based on oxidation level during processing; lighter oxidation preserves more catechins, while heavier oxidation converts them to theaflavins and thearubigins. A typical lightly oxidized Jin Xuan oolong may contain 50–150 mg of total catechins per 8 oz cup, though cultivar-specific quantification data remain limited in published literature.

### How much caffeine is in Jin Xuan tea?

Jin Xuan oolong tea typically contains approximately 20–45 mg of caffeine per 8 oz (240 mL) brewed cup, placing it in the moderate range between green tea (~25–35 mg) and black tea (~40–70 mg). Caffeine content is influenced by oxidation level, steeping time, water temperature, and leaf-to-water ratio; longer steeping at higher temperatures extracts more caffeine. Individuals sensitive to caffeine or managing conditions such as anxiety disorders, hypertension, or pregnancy should account for this content when calculating total daily caffeine intake.

### Is Jin Xuan tea good for weight loss?

There is no clinical evidence specifically evaluating Jin Xuan tea for weight loss. However, extrapolating from oolong tea research, a small RCT by Rumpler et al. (2001) found that full-strength oolong tea increased 24-hour energy expenditure by approximately 2.9% and fat oxidation compared to water. This effect is attributed to the combined thermogenic action of caffeine and catechins, particularly EGCG, which inhibits COMT and prolongs norepinephrine-mediated lipolysis. Effects are modest and should not be considered a primary weight management strategy.

### Can Jin Xuan tea interact with medications?

Jin Xuan tea carries several pharmacologically relevant interactions due to its caffeine, catechin, and vitamin K content. Caffeine can potentiate stimulant medications and reduce the efficacy of adenosine-based antiarrhythmic drugs such as adenosine itself. EGCG has demonstrated inhibition of P-glycoprotein and certain CYP450 enzymes in vitro, which could theoretically alter plasma levels of drugs including statins, beta-blockers, and certain chemotherapy agents, though clinical significance at beverage-level consumption is not well established. Patients on warfarin should be aware that tea's vitamin K content and EGCG's antiplatelet activity may create unpredictable INR fluctuations and should consult their physician.

### What is the origin and growing history of Jin Xuan tea cultivar?

Jin Xuan (also known as 'Milk Oolong') is a cultivar of Camellia sinensis developed in Taiwan in the 1980s through selective breeding for specific agronomic and flavor traits. The cultivar was created by the Taiwan Tea Experiment Station to produce oolong teas with distinctive creamy, milk-like flavor notes and improved yield characteristics. Jin Xuan has since become widely cultivated across Taiwan and other tea-producing regions due to its commercial popularity and consistent quality.

### Is Jin Xuan tea safe for pregnant or breastfeeding women?

Jin Xuan tea contains caffeine (approximately 30-50 mg per 8 oz cup, typical of oolong teas) and should be consumed in moderation during pregnancy and breastfeeding, as high caffeine intake may increase miscarriage risk and pass into breast milk. Most health organizations recommend limiting caffeine to 200 mg daily during pregnancy; however, individual tolerance varies and medical guidance should be sought. No specific safety data exists for Jin Xuan cultivar beyond general Camellia sinensis safety considerations.

### What is the difference between Jin Xuan and other Taiwanese oolong cultivars?

Jin Xuan differs from cultivars like Si Ji Chun and Dong Ding primarily in its creamy, buttery flavor profile and lower oxidation fermentation level (20-30%), whereas other Taiwanese oolongs may have more floral or roasted characteristics. Agronomically, Jin Xuan produces higher yields and is more disease-resistant than some traditional cultivars, making it commercially attractive. The biochemical composition of polyphenols and amino acids varies slightly between cultivars, contributing to distinct taste and mouthfeel characteristics.

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