Lacto-fermented fruits — using the same 2–3% salt brine principle as vegetable fermentations but applied to fruit — produce a category of preserved fruit that is simultaneously sweet, sour, and deeply complex. The fruit's pectin partially degrades during fermentation (softening texture), its sugars partly convert to lactic acid (reducing sweetness, increasing depth), and the volatile aromatic compounds evolve through the fermentation chemistry (new esters forming from the bacterial metabolism, altering the fruit's original aromatic profile).
- **Higher salt percentage than vegetables:** Fruit's higher sugar content accelerates fermentation — a slightly higher salt percentage (3–4%) is needed to control the fermentation rate. [VERIFY] Noma's specific fruit salt percentages. - **Temperature:** 18–22°C — at higher temperatures, the sugar-rich environment favours yeast over Lactobacillus, producing alcohol rather than lactic acid. - **Applications:** Lacto-fermented plum (similar to umeboshi but without the salt-drying process), fermented blueberry, fermented gooseberry — each retaining its fruit character while gaining fermentation complexity. - **The umami development:** The amino acids in the fruit (while much lower than in protein-rich substrates) contribute to a subtle savoury depth in the fermented product — particularly notable in fermented tomatoes, which develop glutamate concentrations noticeably higher than fresh tomatoes.
Noma Fermentation