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+# Role Substitution Logic
+
+When an ingredient isn't available, think in **categories, not products**. Ask: *what role does this ingredient play, and what else plays that role locally?*
+
+See [[Flavor Profile Formulas]] to match available ingredients to a profile. See [[Flavor Sense]] to understand why each role matters.
+
+---
+
+## Acid
+
+The goal is brightness and palate reset. Anything with a sour, mouth-watering quality works.
+
+Fresh citrus (lemon, lime, orange) → other citrus → mild vinegar (rice, white wine) → strong vinegar diluted with water (1:1) → fermented liquid (pickle brine, yogurt whey, kombucha) → sour dairy (yogurt, crème fraîche, sour cream)
+
+**Dry acid:** Sumac or tamarind powder add sourness without any liquid — useful when you don't want to add moisture to the dish.
+
+---
+
+## Fat
+
+The goal is flavor dissolution and heat conduction. Any fat works for cooking; flavored fats add profile character.
+
+Neutral high-smoke oil (canola, sunflower, grapeseed, avocado) → animal fat (lard, ghee, tallow, duck fat) → olive oil (use at lower heat only — not for searing) → coconut oil (adds tropical character, shifts profile toward South Asian or Southeast Asian)
+
+**Note:** Coconut milk is both a fat and a liquid — it creates a sauce rather than a searing medium. Use it for braises, not for high-heat cooking.
+
+---
+
+## Aromatic
+
+Garlic and onion are available almost everywhere on earth and form a valid aromatic base for any profile. Secondary aromatics add regional specificity.
+
+**Primary (universal):** Garlic + onion in any form (fresh, dried, powder as last resort)
+
+**Secondary aromatics and their profiles:**
+- Ginger → East Asian, Southeast Asian, South Asian
+- Lemongrass → Southeast Asian (no real substitute; omit if unavailable)
+- Shallot → French, Southeast Asian (substitute: white part of scallion, or mild onion)
+- Leek → French, Eastern European (substitute: white part of scallion)
+- Cumin → Latin American, Middle Eastern, South Asian
+- Dill → Eastern European (no real substitute; omit if unavailable)
+- Caraway → Eastern European (substitute: fennel seed, a milder anise note)
+
+---
+
+## Umami
+
+The goal is depth and a sense of completeness. Layer sources when possible — the effect compounds.
+
+Brown your protein well (Maillard) → add a fermented condiment → add concentrated tomato (paste or canned) → add dried mushrooms (rehydrate in hot water; use both mushrooms and soaking liquid) → finish with aged or hard cheese
+
+**Regional fermented condiments you might encounter:**
+- East / Southeast Asia: soy sauce, fish sauce, miso, shrimp paste, oyster sauce
+- South Asia: tamarind paste, achaar (pickled condiment)
+- Middle East / North Africa: preserved lemon, harissa
+- Europe: Worcestershire, Dijon mustard, anchovy paste, aged cheese (parmesan, pecorino)
+- Latin America: chipotle in adobo, mole paste
+- West Africa: dawadawa, ogiri, fermented fish paste
+
+---
+
+## Starch
+
+The goal is volume and satiety. Any carbohydrate that absorbs liquid and flavor works.
+
+Any grain cooked by absorption (rice, millet, farro, bulgur, quinoa, couscous) → root vegetables (potato, sweet potato, yuca, taro, plantain) → legumes as starch (beans, lentils, chickpeas) → flatbread or commercial bread → pasta or noodles
+
+**Fastest starches:** Couscous (boiling water + lid, 5 min), instant noodles (discard seasoning packet), pre-cooked grain pouches
+
+---
+
+## Protein
+
+The goal is substance and the primary browning opportunity. Any protein that can be seared works.
+
+Fresh meat → fresh fish or shellfish → eggs → firm tofu or tempeh → canned protein (tuna, chicken, sardines, chickpeas) → nuts and seeds (texture + fat + protein, no browning needed)
+
+**Budget hierarchy within meat:** Chicken thighs → pork shoulder or belly → beef chuck → chicken breast → any offal (liver, heart — highly nutritious, very affordable)
+
+---
+
+*Return to [[Weekly Planning Template]] · See profiles: [[Flavor Profile Formulas]] · See mechanisms: [[Flavor Sense]]*