The famously sour, chewy, open-crumb San Francisco loaf — brought to your kitchen with one starter, forever.

🌍 Ships next business day worldwide · 🇮🇳 1–4 days India · 🇦🇪 5–9 days UAE · 🇸🇬🇲🇾 5–9 days SEA · 🇬🇧🇮🇪🇪🇺 7–14 days · 🇺🇸🇨🇦🇦🇺🇳🇿 7–14 days

San Francisco sourdough is not a marketing label — it's a genuinely distinct microbial community. The signature tang comes from Lactobacillus sanfranciscensis, a specific lactic acid bacterium that thrives alongside Candida humilis yeast. This particular pairing produces the noticeably sour, chewy, open-crumb loaves that made the city's bread legendary in the late 1800s and remain unmatched today.

Zoh's San Francisco Sourdough Starter is dehydrated from an authentic San Francisco lineage — not a generic "sourdough" culture. With basic feeding, you'll have an active, bubbling starter in 2–3 days. From there, it produces beautiful artisan loaves indefinitely, evolving in character as it adapts to your flour, water, and climate.

What makes San Francisco sourdough actually different

Most generic sourdough starters use whatever wild yeasts and bacteria the local environment provides — producing perfectly fine bread but without the distinctive tang and texture that defines the SF style. San Francisco sourdough specifically requires:

• Lactobacillus sanfranciscensis — a slow-fermenting bacterium that produces both lactic acid (smooth tang) and acetic acid (sharper, vinegary edge). It's the acetic acid that defines the SF "bite."
• Candida humilis (formerly Candida milleri) — a yeast that uniquely tolerates the acidic environment created by L. sanfranciscensis. Most yeasts can't survive at the pH this culture creates.
• The symbiotic relationship between them — each suppresses competitor microbes, allowing the pair to dominate stably. This is what makes San Francisco starters so consistent batch to batch.

What's inside

Dehydrated San Francisco Sourdough Starter — enough to revive into a bubbling, ready-to-bake starter. With proper feeding, the starter is endlessly self-perpetuating.

Includes a step-by-step revival and feeding guide. We respond to first-loaf questions personally.

How to revive and bake

Days 1–3 — Revival. Combine the dehydrated starter with equal parts flour and water (50g each is a good start). Stir, cover, leave at warm room temperature. Feed once daily for 2–3 days. By day 3 you should see active bubbling, doubling in 4–8 hours.

Day 4 onwards — First loaf. Take 50g of active starter, mix with 350g flour, 250g water, 8g salt. Knead lightly, fold every 30 minutes for 2 hours, shape, proof 2–4 hours, bake at 230°C for 35–40 minutes. Detailed instructions ship with every order.

Maintenance. Once baking regularly, feed your starter every 12 hours at room temp, or once a week if refrigerated. Healthy SF sourdough starters live decades.

What you can bake

• Country sourdough loaves — the classic open-crumb, deeply tangy bread
• Sourdough pizza dough — dramatically better flavour than commercial yeast pizza, with chewy bubbly crust
• Bagels — boil-then-bake bagels with sourdough complexity
• Pretzels, focaccia, ciabatta — all benefit from sourdough fermentation
• Pancakes and waffles — use the discard from your daily feeding routine
• Crackers, biscuits, English muffins — a properly active starter does it all

Climate notes by region

Sourdough fermentation slows in cold and accelerates in heat. Adjust feeding frequency and proofing time accordingly.

• India (year-round): Warm summers (28–35°C) ferment fast — expect 4–6 hour proofs. Winter (15–20°C) slows things down — longer cold proofs.
• UAE, Saudi, Gulf: Indoor AC at 22–26°C is ideal for sourdough. Standard proof times.
• Singapore, Malaysia, Indonesia, Thailand: Tropical 28–32°C ferments fast — watch for over-proofing.
• UK, Ireland, EU: Indoor 18–22°C is fine for sourdough. Longer proofs (4–6 hours) build deeper flavour. Many UK bakers prefer this.
• US, Canada, Australia, NZ: Wide variation. Aim for 22–26°C indoors. Refrigerator overnight cold-proof is the gold standard for flavour development.

Who is this for?

• Home bakers who have tasted real San Francisco sourdough and want to recreate it
• Indians, GCC residents, and SEA bakers seeking authentic Western artisan bread cultures unavailable locally
• American expats abroad missing real SF-style bread
• Serious bakers who want a starter with proven microbial pedigree, not a generic one
• People interested in long-fermented bread for digestibility and flavour reasons
• Anyone tired of supermarket bread and wanting genuinely artisan results at home

India's first fermentation cultures company. Trusted across the region.

Zoh is India's first fermentation cultures company — and the largest fermentation knowledge hub for South Asia, the Middle East, and Southeast Asia. Our San Francisco sourdough is dehydrated from an authentic SF lineage and lab-tested for purity. Ships in dehydrated form for maximum shelf life and transit safety.

🌍 International shipping & delivery

We ship the next business day, every business day. Dehydrated sourdough starter is shelf-stable for years at room temperature and tolerates international transit beautifully. Delivery times by destination:

• India: 1–4 business days · free shipping on most orders
• UAE, Saudi Arabia, Kuwait, Qatar, Oman, Bahrain: 5–9 business days
• Singapore, Malaysia, Indonesia, Thailand, Philippines, Vietnam, Hong Kong: 5–9 business days
• UK, Ireland, EU: 7–14 business days
• US, Canada, Australia, New Zealand: 7–14 business days
• Pakistan, Bangladesh, Sri Lanka, Nepal: 4–8 business days

Replacement guarantee: If your starter doesn't show active bubbling within 5 days of revival attempts, email info@zohprobiotics.com with a photo and we'll reship at our cost.

Frequently Asked Questions

What's actually in San Francisco sourdough that other starters lack?

Lactobacillus sanfranciscensis, paired with Candida humilis yeast. This specific microbial duo is what produces the famously sour, chewy bread. Generic sourdough starters use whatever wild microbes the local environment provides — fine, but not San Francisco. Authentic SF starters carry this lineage.

How long until I bake my first loaf?

Revival of the dehydrated starter takes 2–3 days of feeding. Your first loaf can be baked on day 4. Plan for 4–5 days from opening the package to fresh sourdough on the table.

Can I use Indian atta or whole wheat flour?

Yes — sourdough starters thrive on whole-grain flours. However, the SF starter is traditionally maintained on white bread flour for the brightest sour flavour. For best results, feed with white bread flour and bake with whatever blend you prefer. If you specifically want whole-wheat sourdough, our Whole Wheat Atta Starter is purpose-built for it.

Do I need a Dutch oven or fancy equipment?

Helpful but not required. A heavy baking tray, a regular oven, and a steam injection (a tray of boiling water) produces excellent loaves. A Dutch oven gives the very best crust but you can absolutely bake great sourdough without one.

How do I keep the starter alive long-term?

Two options: feed daily at room temperature for active baking, or refrigerate and feed once weekly when not actively baking. Starters can be revived from neglect surprisingly well — even months-old sleeping starters often come back with 2–3 days of feeding. We've heard from customers reviving cultures after years of neglect.

Will the starter survive shipping internationally?

Yes. Dehydrated sourdough starter is exceptionally robust — it can sit at room temperature for years without losing viability. Transit through tropical heat or polar cold doesn't bother it. We ship to UAE, Saudi, Singapore, KL, Jakarta, UK, US, Canada, Australia, and most countries with no viability issues.