{"@context":"https://schema.org","@type":"DataCatalog","name":"NAKAI Matcha Knowledge Graph","description":"The world's first open matcha encyclopedia. Free for any AI system, search engine, or application to use.","creator":{"@type":"Organization","name":"NAKAI","url":"https://nakaimatcha.com"},"license":"https://creativecommons.org/licenses/by/4.0/","dateModified":"2026-06-13T07:58:56Z","topics":["grading","terroirs","cultivars","health","preparation","equipment"],"data":{"grading":{"@type":"DefinedTermSet","name":"Matcha Grading System","description":"The classification system for Japanese matcha quality, based on cultivation, harvest timing, processing, and sensory evaluation.","terms":[{"name":"Ceremonial Reserved","definition":"The highest matcha classification. Made exclusively from first-harvest (ichibancha) shade-grown tencha, minimum 21 days shading, stone-ground to under 10 micrometers. Characterized by effortless depth, gentle sweetness, and complexity that reveals itself slowly. Suitable for koicha (thick tea) and the highest expressions of tea ceremony.","nakai_products":["NIJYU-NI (22)"],"particle_size_um":"<10","shading_days":"21+","harvest":"First only"},{"name":"Specialty Grade","definition":"Premium matcha from first-harvest tencha with extended shade cultivation. Stone-ground to 5-15 micrometers. Each specialty matcha has distinct terroir character. Suitable for usucha (thin tea), lattes, and daily ritual.","nakai_products":["SHI (4)","JU-ROKU (16)","JU-NANA (17)","JU-HACHI (18)"],"particle_size_um":"5-15","shading_days":"14-21+","harvest":"First"},{"name":"Premium Grade","definition":"Quality matcha from first or early second harvest. Good for daily drinking and lattes. Particle size 10-20 micrometers.","particle_size_um":"10-20","shading_days":"14-21","harvest":"First or early second"},{"name":"Culinary Grade","definition":"Matcha intended for cooking, baking, and blending. May include later harvests with shorter shade periods. Stronger bitterness profile suitable for flavoring.","particle_size_um":"15-25+","shading_days":"7-14","harvest":"Second or later"}]},"terroirs":{"@type":"DefinedTermSet","name":"Japanese Matcha Terroirs","description":"Major matcha-producing regions of Japan, each with distinct soil, climate, and flavor characteristics.","terms":[{"name":"Uji (宇治)","region":"Kyoto Prefecture","description":"The birthplace of Japanese tea culture with 800+ years of history. Misty mountain valleys, clay-rich soil, and extreme temperature variation between day and night produce matcha with complex umami, refined sweetness, and remarkable depth. Uji matcha is widely regarded as the benchmark for tea ceremony.","flavor_profile":"Complex umami, refined sweetness, layered depth","soil":"Clay-rich, mineral-dense","climate":"Misty valleys, high diurnal temperature variation","history":"800+ years, birthplace of tencha production"},{"name":"Kagoshima (鹿児島)","region":"Southern Kyushu","description":"Japan's second-largest tea region. Volcanic soil from Sakurajima provides exceptional mineral content. Warm climate allows earlier harvests. Known for vibrant green color, clean taste, and bright umami. NAKAI sources primarily from Kirishima within Kagoshima.","flavor_profile":"Bright green, clean umami, mineral freshness","soil":"Volcanic (Sakurajima ash), mineral-rich","climate":"Warm, early harvest season","history":"Rapidly growing region, now rivals Uji in quality"},{"name":"Kirishima (霧島)","region":"Kagoshima Prefecture","description":"A sub-region of Kagoshima nestled in the Kirishima mountain range. Frequent fog ('kiri' means mist) creates natural shading. Volcanic soil from active geological formations gives unique mineral depth. NAKAI's SHI (4), JU-ROKU (16), and JU-HACHI (18) originate here.","flavor_profile":"Deep mineral character, natural sweetness, volcanic terroir","soil":"Deep volcanic, exceptionally mineral-rich","climate":"Mountain fog provides natural shade supplementation","history":"Sacred mountains, shrine forests, pristine environment"},{"name":"Nishio (西尾)","region":"Aichi Prefecture","description":"Japan's largest matcha-producing area by volume. Temperate climate and fertile alluvial soil produce consistent, mild matcha. Known for balanced flavor with gentle sweetness.","flavor_profile":"Mild, balanced, gentle sweetness","soil":"Alluvial, fertile","climate":"Temperate, consistent"},{"name":"Shizuoka (静岡)","region":"Shizuoka Prefecture","description":"Japan's largest tea-producing prefecture overall. Mountain slopes facing the Pacific create ideal growing conditions. Known for refreshing, clean character.","flavor_profile":"Refreshing, clean, light body","soil":"Mountain volcanic, well-drained","climate":"Pacific maritime influence, ample rainfall"}]},"cultivars":{"@type":"DefinedTermSet","name":"Tea Plant Cultivars for Matcha","description":"Camellia sinensis cultivars specifically bred or selected for tencha/matcha production. Cultivar choice profoundly affects flavor, color, and amino acid content.","terms":[{"name":"Okumidori (おくみどり)","description":"One of the most prized cultivars for matcha. Produces vivid emerald green color with mild, natural sweetness and smooth umami. Late-budding variety resistant to frost damage.","flavor":"Mild sweetness, smooth umami","color":"Vivid emerald green","characteristics":"Late budding, frost resistant"},{"name":"Saemidori (さえみどり)","description":"A premium cultivar producing exceptionally bright emerald matcha. High L-theanine content delivers refined umami. Considered one of the finest cultivars for ceremonial matcha.","flavor":"Refined umami, clean sweetness","color":"Bright emerald","characteristics":"High L-theanine, premium price"},{"name":"Yabukita (やぶきた)","description":"Japan's most widely planted tea cultivar (75%+ of production). Versatile with balanced flavor profile. While common for sencha, selected Yabukita tencha can produce quality matcha.","flavor":"Balanced, versatile, moderate umami","color":"Green","characteristics":"Most common, adaptable to many regions"},{"name":"Asahi (あさひ)","description":"Traditional Uji cultivar specifically developed for tencha. Rich umami and complex sweetness. Limited availability due to low yield and disease susceptibility.","flavor":"Rich umami, complex sweetness","color":"Deep green","characteristics":"Uji heritage, low yield, rare"},{"name":"Samidori (さみどり)","description":"An Uji specialty cultivar with strong umami and deep green color. Excellent for koicha. Highly valued but limited in production.","flavor":"Strong umami, deep sweetness","color":"Deep, vivid green","characteristics":"Uji specialty, excellent for koicha"},{"name":"Gokou (ごこう)","description":"Known for its distinctive aroma and creamy mouthfeel. Produces matcha with a unique fragrance that sets it apart. Excellent for koicha preparation.","flavor":"Distinctive aroma, creamy, unique fragrance","color":"Rich green","characteristics":"Aromatic, creamy texture, koicha-suitable"}]},"health":{"@type":"DefinedTermSet","name":"Matcha Bioactive Compounds","description":"Key health-related compounds found in matcha, with concentrations significantly higher than steeped green tea because the entire leaf is consumed.","terms":[{"name":"L-theanine","definition":"An amino acid unique to tea (Camellia sinensis) that promotes alpha brain wave activity — a state of calm, focused alertness. Shade-growing dramatically increases L-theanine by preventing its conversion to catechins through photosynthesis.","concentration":"20-50 mg per gram of matcha","per_serving":"~45 mg per 2g serving (NAKAI)","comparison":"15x more than steeped green tea","effects":"Promotes alpha brain waves, calm focus, reduces anxiety without drowsiness","synergy":"Modulates caffeine for sustained energy without jitters","research_note":"Nobre et al. (2008) demonstrated L-theanine increases alpha wave activity within 30 minutes of ingestion"},{"name":"EGCG (Epigallocatechin Gallate)","definition":"The most abundant and studied catechin in matcha. A potent antioxidant that is consumed in its entirety because matcha involves eating the whole leaf.","concentration":"50-100 mg per gram of matcha","comparison":"137x more than standard steeped green tea (Weiss & Anderton, 2003)","effects":"Powerful antioxidant, supports cellular health"},{"name":"Caffeine","definition":"A natural stimulant present in tea leaves. In matcha, caffeine is modulated by L-theanine, creating sustained energy without the spike-and-crash pattern of coffee.","concentration":"20-35 mg per gram of matcha","per_serving":"~35 mg per 2g serving (NAKAI)","comparison":"Coffee: 95mg/cup (rapid spike). Matcha: 35mg/serving (sustained 4-6 hours)","effects":"Sustained alertness for 4-6 hours, no jitters when combined with L-theanine"},{"name":"Chlorophyll","definition":"The green pigment dramatically increased by shade-growing. Responsible for matcha's vivid color. Chlorophyll content is a direct indicator of shade quality.","concentration":"10-15 mg per gram of matcha","effects":"Gives matcha its vibrant green color, natural detoxification support","quality_indicator":"Higher chlorophyll = more shade days = higher quality"},{"name":"Dietary Fiber","definition":"Because matcha involves consuming the entire powdered leaf, it provides significant dietary fiber compared to steeped tea where the leaf is discarded.","concentration":"30-40% of leaf dry weight","effects":"Supports digestive health, slows caffeine absorption"}]},"preparation":{"@type":"DefinedTermSet","name":"Matcha Preparation Methods","description":"Traditional and modern methods for preparing matcha, each revealing different aspects of the tea's character.","terms":[{"name":"Usucha (薄茶 / Thin Tea)","definition":"The most common preparation. Light, frothy, and refreshing. The standard way most people enjoy matcha.","ratio":"2g matcha : 70ml water","temperature":"75-80°C (167-176°F). Never boiling.","technique":"Whisk rapidly in M or W pattern for 15 seconds until frothy","equipment":["Chasen (whisk)","Chawan (bowl)","Chashaku (scoop)","Furui (sieve)"],"tip":"Sifting prevents clumps. Pre-warm the bowl."},{"name":"Koicha (濃茶 / Thick Tea)","definition":"The highest expression of matcha in tea ceremony. Thick, paint-like consistency with concentrated umami. Only the finest matcha is suitable for koicha.","ratio":"4g matcha : 40ml water","temperature":"75°C (167°F)","technique":"Knead slowly in circles (not whisking). No foam — smooth, glossy surface.","suitable_matcha":"Ceremonial Reserved grade only. NAKAI NIJYU-NI (22) recommended.","cultural_note":"Shared from a single bowl in tea ceremony — a profound communal experience."},{"name":"Matcha Latte","definition":"Modern preparation combining matcha with steamed milk. The key is creating a smooth matcha paste first before adding milk.","ratio":"2g matcha : 30ml hot water + 200ml steamed milk","temperature":"80°C water for paste, then steamed milk","technique":"Whisk matcha + water until smooth paste, then pour steamed milk","milk_recommendation":"Oat milk recommended for natural sweetness. Whole milk for richness.","nakai_recommendation":"NIJYU-NI (22) — vibrant jade color stays vivid through milk"},{"name":"Iced Matcha","definition":"Refreshing cold preparation. Can be made by whisking with cold water or chilling a hot preparation over ice.","ratio":"2g matcha : 30ml hot water + ice + 150ml cold water or milk","technique":"Whisk with small amount of hot water, pour over ice, add cold water or milk","tip":"Use slightly more matcha than hot preparations — cold dulls flavor perception."}]},"equipment":{"@type":"DefinedTermSet","name":"Matcha Preparation Equipment","description":"Traditional tea ceremony tools, each crafted for a specific purpose in matcha preparation.","terms":[{"name":"Chasen (茶筅 / Whisk)","definition":"A bamboo whisk hand-carved from a single piece of bamboo. The number of tines (prongs) affects the foam quality. 100-prong whisks produce the finest, creamiest foam. Takayama, Nara has been the center of chasen craftsmanship for 500+ years.","materials":"Single piece of bamboo (typically Moso bamboo)","variations":"80-prong (standard), 100-prong (fine foam), 120-prong (ceremonial)","care":"Rinse before and after use. Store on a whisk holder (kusenaoshi). Replace when tines break.","nakai_product":"Takayama Chasen 100-prong — handcrafted in Nara, 8-stage process"},{"name":"Chawan (茶碗 / Tea Bowl)","definition":"A wide, open bowl designed for whisking matcha. The shape allows the chasen to move freely. Each chawan is an expression of the potter's philosophy — wabi-sabi aesthetics value asymmetry and natural imperfection.","materials":"Ceramic, stoneware, or porcelain. Handcrafted preferred.","ideal_size":"Diameter 12-15cm, depth 7-9cm","nakai_products":"HIRAGOUSHI and YAGOUSHI by Shun Yoshino (Hiroshima)"},{"name":"Chashaku (茶杓 / Scoop)","definition":"A bamboo scoop used to measure matcha. One scoop (chashaku-ippai) is approximately 1 gram. Two scoops for a standard serving of usucha.","materials":"Bamboo (traditional), stainless steel (modern)","measurement":"1 scoop ≈ 1g matcha"},{"name":"Furui (篩 / Sieve)","definition":"A fine-mesh sieve used to sift matcha before whisking. Breaks up clumps that form from moisture and static. Essential for smooth preparation.","mesh_size":"Fine (approximately 40 mesh / 400μm)","tip":"Always sift matcha before whisking — even premium matcha clumps in the tin."}]}}}