Autumn Spinach and Tofu Soup | IDDSI Level 3–4 Recipe

IDDSI Level 3–4 (Liquidised / Pureed) | 15 minutes prep, 25 minutes cooking | Easy

Autumn spinach and tofu soup (菠菜豆腐湯, bo choi dau fu tong) blends blanched spinach into a vivid green soup base and combines it with silken tofu for a smooth, protein-rich, iron-dense autumn soup. Spinach provides plant iron, vitamin K, folate and beta-carotene; silken tofu adds complete plant protein and calcium — making this an ideal nutritional supplement for vegetarian elderly residents or anyone requiring additional iron. Adjusting the blending step produces either IDDSI Level 3 (Liquidised) or Level 4 (Pureed) to match individual dietary prescriptions.

Ingredients (2–3 servings)

• 200g fresh spinach (roots removed, washed)
• 200g silken tofu (Japanese-style 絹豆腐)
• 800ml vegetable stock (or water with vegetable powder)
• 1 teaspoon grated ginger (juice only, fibres discarded)
• 1 tablespoon light soy sauce
• A few drops sesame oil
• Salt to taste
• 1 teaspoon cornflour (optional, for texture adjustment)

Method

1. Blanch spinach in boiling water for 1 minute; immediately transfer to ice water to preserve colour. Squeeze out excess water.
2. Blend blanched spinach with 200ml vegetable stock until completely smooth; pass through a fine-mesh strainer to remove all fibres — critical for IDDSI Level 3.
3. Mash silken tofu with a fork until no lumps remain (Level 4) or blend to a completely smooth puree (Level 3).
4. Warm remaining vegetable stock with ginger juice over medium heat.
5. Add spinach puree; stir to combine and bring to a gentle simmer.
6. Add tofu puree; stir gently and simmer 3 minutes over low heat.
7. Season with soy sauce, sesame oil and salt.
8. If additional thickening is needed for IDDSI Level 4: stir in cornflour slurry while stirring; heat until target texture is reached.
9. Pass through a strainer before serving for IDDSI Level 3.

Texture Test

IDDSI Level 3 confirmation: The soup should flow continuously when poured from a spoon at 5cm height — slower than water but without stopping. A fork held over the soup should allow slow dripping through the tines. No particles or fibrous strands should be visible or detectable.

IDDSI Level 4 confirmation: The soup should not drip through fork tines. A spooned portion should slowly spread on a plate. Fork-back pressure should reveal no particles larger than 4mm.

Safety Notes

⚠️ Spinach fibres — Spinach contains coarse fibres that can survive blending. For IDDSI Level 3, strain through a fine-mesh sieve (80–100 mesh) after blending. Even for Level 4, passing through a coarser strainer is recommended to remove fibrous strands.

⚠️ Oxalate content — Spinach is high in oxalates, which may interfere with calcium and iron absorption and contribute to kidney stones in susceptible individuals. Blanching removes a significant proportion of oxalates. Consult a physician before using spinach regularly if the individual has a history of kidney stones.

⚠️ Silken tofu heat sensitivity — Silken tofu becomes fragile when heated; excessive heating can cause protein to granulate, creating lumps that compromise IDDSI compliance. Heat gently over low heat and stir carefully.

⚠️ Ginger fibres — Use ginger juice only — grate fresh ginger and squeeze the juice through a fine strainer, discarding the fibrous pulp. Ginger fibres are not compliant with IDDSI Level 3 or 4.

Sourcing in Hong Kong

• Fresh spinach: Wet market vegetable stalls; choose bright-green leaves with thin, tender stems and no yellowing; autumn and winter spinach is denser and more flavourful — producing a deeper-coloured puree
• Silken tofu (絹豆腐): Supermarket refrigerated tofu section; Japanese-style silken tofu produces the smoothest, most even puree; avoid firm or extra-firm tofu — the coarser protein structure does not blend as smoothly

Nutrition

Approximately 120 kcal per serving (10g protein, 2.5mg iron, 180mg calcium, high vitamin K). Spinach plant iron (non-haem iron) is enhanced by pairing with vitamin C-rich foods; silken tofu provides complete plant protein and calcium — particularly important for vegetarian elderly individuals who may struggle to meet protein and calcium needs through other texture-modified foods. Low calorie and high nutrient density make this suitable for individuals requiring nutritional support within a calorie-controlled diet.

Cultural Note

Spinach and tofu soup (菠菜豆腐湯) is a staple of Cantonese home cooking — simple, light, nutritious and prepared year-round across the region. In Cantonese dietary culture, spinach in autumn is associated with “nourishing the blood and brightening the eyes” (養血明目), while tofu provides plant protein as a meat alternative — a pairing that reflects traditional Cantonese wisdom about balanced eating. This IDDSI-adapted version makes this everyday family soup accessible to elderly residents with dysphagia, supporting both their iron and protein needs in a culturally familiar form.