Seaweed & Pork Bone Soup | IDDSI Level 3 Recipe

IDDSI Level 3 (Liquidised) | 90 minutes (mostly unattended) | Medium

海帶豬骨湯 (seaweed and pork bone soup) is a beloved Cantonese slow-simmered soup that draws deep, mineral-rich flavour from pork bones and the ocean umami of dried kelp (kombu-style seaweed). Long simmering transforms the bones into a collagen-rich, gelatinous broth and softens the seaweed to a velvety consistency that blends smoothly. The resulting Level 3 soup is one of the most nutrient-dense options in this collection: rich in iodine, calcium, collagen peptides, and the natural glutamates that stimulate appetite even in residents with diminished taste sensation.

Ingredients (4 servings)

Main:

• 500g pork bones (排骨 or 豬筒骨), blanched
• 30g dried kelp / kombu-style seaweed (海帶), soaked 30 minutes in cold water and rinsed
• 1.5 litres water
• 3 slices fresh ginger
• 1 teaspoon rice wine (米酒) or Shaoxing wine

Seasoning:

• Salt to taste
• White pepper to taste
• 1 teaspoon sesame oil

Method

1. Blanch pork bones: place in a pot, cover with cold water, bring to a boil and boil for 5 minutes. Drain, rinse thoroughly under cold running water, and scrub off any impurities. This step is essential to remove blood residue and ensures a clean, clear broth.
2. Soak dried seaweed in cold water for 30 minutes until fully rehydrated and softened. Drain and rinse; cut into smaller pieces to fit the pot.
3. Combine blanched pork bones, softened seaweed, ginger slices and rice wine in a large pot. Add 1.5 litres of water.
4. Bring to a vigorous boil over high heat, skim off any foam that forms. Reduce to a low simmer, cover partially, and cook for 75 minutes.
5. After simmering, the meat on the pork bones should be very tender and beginning to separate. Remove bones, ginger slices; strip any remaining meat from the bones and add the meat back to the pot; discard bones.
6. Transfer all contents (broth, seaweed, meat) to a blender. Blend on high speed for 2 minutes until completely smooth.
7. Pass through a fine-mesh sieve into a clean saucepan; press firmly to extract all liquid; discard any tough fibrous residue.
8. Return to low heat, season with salt, white pepper and sesame oil. Serve immediately.

Texture Test

IDDSI Level 3 confirmation: Tilt a loaded spoon — the soup flows slowly and continuously, coating the back of the spoon. The natural gelatin from pork bones provides gentle body. No seaweed fibre strands remain. IDDSI syringe test: 1–10ml expelled over 10 seconds.

Safety Notes

Blanching pork bones is non-negotiable — skipping this step results in murky, impurity-laden broth that affects both taste and safety.

Seaweed iodine content — seaweed is high in iodine; residents with thyroid conditions should have this soup cleared with their physician before regular consumption.

Bone removal — ensure all bone fragments are removed before blending. After stripping meat from bones, run hands carefully over the meat to detect any small bone chips.

Sourcing Outside Hong Kong

For international care kitchens and home cooks outside Hong Kong, Cantonese ingredients are widely available at East and Southeast Asian grocery stores:

• United Kingdom: Wing Yip (Birmingham, London, Manchester), See Woo (London), Loon Fung (London)
• United States: 99 Ranch Market (West Coast), H Mart (East Coast), local Chinatown grocers
• Canada: T&T Supermarket (national chain), local Asian markets
• Australia: Burlington Supermarket, Tang’s, local Chinese grocers in Chinatown precincts
• Singapore & Malaysia: Sheng Siong, NTUC FairPrice (Singapore); Tesco, Mydin (Malaysia)
• Online: Sous Chef (UK/EU), Amazon.com (US), Yami.com (US)

Key Cantonese pantry ingredients: East Asian grocers including Wing Yip (UK), H Mart (US/CA), T&T (CA), and Sheng Siong (Singapore) cover most items in this recipe.

If a specific ingredient is unavailable in your region, the recipe notes alternative substitutions in the Ingredients section. For dishes requiring fresh Cantonese-specific ingredients (e.g. preserved century egg, fresh rice noodle rolls), check with your local East Asian grocer before substituting — texture compliance for IDDSI levels may require specific products.

Nutrition

Approximately 155 kcal per serving (250ml), 12g protein, 8g fat. Pork bone broth is exceptionally rich in collagen peptides that support joint health, skin integrity and gut lining — particularly valuable for elderly residents with mobility issues or recovering from injury. Seaweed provides iodine (essential for thyroid function), calcium, magnesium and natural glutamates that act as appetite stimulants.

Cultural Note

海帶豬骨湯 is a classic Cantonese “old fire soup” (老火湯) — the slow-simmered tradition of cooking soup for 1–2 hours to extract maximum nutrition and flavour from natural ingredients. In traditional Cantonese belief, such soups are considered fundamental to maintaining good health and vitality. Presenting this soup in Level 3 blended form makes the full nourishment of this centuries-old tradition accessible to residents at every stage of dysphagia — preserving the intent of care in its original, deeply cultural form.