Five ways to keep pulp
For buyers, NPD and QA teams sourcing bulk fruit pulp and purée
Fruit spoils. Every pulp on the market is a different bargain struck with that fact — some trade away colour, some trade away shelf life, some trade away the markets you can sell into.
Three processes work against pulp at once: microorganisms ferment the sugars, the fruit's own enzymes brown the colour, and oxygen oxidises vitamin C, carotenoids and aroma. Chemistry, cold, heat and barrier packaging are the four tools available.
What you are actually buying
Each format is named by the barrier it relies on, because that is what determines how it behaves in your factory.
The trade-offs in one table
Figures come from separate sources and are drawn together for orientation, not as one experiment.
| Format | Holds it with | Shelf life | Storage | Preservative | Main quality cost |
|---|---|---|---|---|---|
| Chemically preserved | SO₂, benzoate, sorbate | ~6 mo ambient · ~10 mo at 4 °C | Ambient | Yes, declarable | Bleached colour, sulphurous note, export restrictions |
| Frozen | Cold | 8–12 mo quality life | −18 °C, unbroken | No | None material — the cost is logistical |
| Pasteurised / hot-fill | Heat, then pack | Short to medium | Chilled or ambient | Sometimes | Long hold times degrade vitamin C and carotenoids |
| Canned | Heat in container | Long | Ambient | No | Overcooking at the pack wall; cooked notes |
| Aseptic | Heat in flow + sterile pack | 12–18 mo ambient (typ. spec) | Ambient | No | Slow drift in colour and flavour over ambient storage |
Why SO₂ decides which markets you can sell into
This is the part of the decision that has nothing to do with taste. Sulphite limits differ by an order of magnitude between the market you buy in and the markets you may want to sell in.
- India, industrial-use pulp — 1,000 ppm. The FSSAI category for pulp with preservatives.
- EU retail foods — 10–100 ppm (varies by product; some categories prohibit it entirely).
- US — 10 ppm undeclared threshold; above that it must be labelled.
If you buy 1,000 ppm Indian pulp and want to sell a finished product in the EU, you either dilute below 10 ppm (losing most of the fruit character), treat it further (adding process cost and a different preservative declaration), or source differently.
Aseptic pulp sidesteps the issue entirely: no SO₂, no declaration, no market restriction from the preservative itself.
What aseptic processing actually guarantees — and what it does not
Aseptic processing gives you commercial sterility and ambient stability without preservatives. It does not freeze quality in place. Over months at ambient temperature, colour and flavour still drift — slowly, but measurably.
A 12-month aseptic mango pulp stored at 35 °C will be darker and flatter than the same pulp frozen at −18 °C. Both are safe; neither is spoiled; but they are not interchangeable in a premium finished product.
The honest pitch for aseptic is logistics and market access, not that it is the best preservation method in every quality dimension.
How to use this when sourcing
- Start from your finished product and its target markets — that determines which preservative and storage constraints you can accept.
- Work backwards to the format that fits your cold chain capability and production schedule.
- Ask for a Certificate of Analysis on every lot; compare Brix, acidity, colour score, and SO₂ (if applicable) against your spec.
- If comparing prices across formats, normalise to delivered cost per kg of usable pulp at your factory, including storage and waste.