Hot fill, aseptic or HPP: choosing a preservation route
The preservation decision drives your capex, your shelf life and your clean-label positioning. Take it before formulation, not after.
Read the article →The lab sample was perfect. The pilot run was good. The first plant batch was unsellable. This sequence is so common that we plan for it, and the causes are almost always in the same six places.
1. Shear and mixing energy
A bench mixer and a 2,000 litre tank do not impart the same energy per unit volume. Emulsions destabilise, hydrocolloids fail to hydrate fully, and particles distribute unevenly. Specify mixing in terms of tip speed and time, not equipment settings.
2. Heating and cooling rates
A small vessel heats and cools in minutes; a large one takes an hour. That extra time at temperature drives colour, flavour and viscosity changes that never appeared at pilot scale. The total thermal load is a formulation parameter and must be specified as one.
3. Holding time before filling
In the lab, product goes from process to pack in minutes. In the plant it may wait an hour in a buffer tank. Viscosity builds, separation begins and temperature drifts. Always trial with the realistic hold time included.
4. Ingredient grade and supplier
Development often uses sample material from a supplier's technical team - a better grade than the commercial lot the purchase team eventually buys. Lock the exact grade and supplier into the specification before the trials, and run a confirmation batch on commercial material.
5. Water
Lab water is treated. Plant water may be borewell water with different hardness, alkalinity and mineral content. This affects pH, hydration, colour and taste more than most teams expect, and it varies by season.
6. Operators
A development chemist follows an implicit protocol. An operator follows the SOP as written on the third shift of a long week. If the SOP does not state the tolerance and the sequence explicitly, the batch will vary. Write the SOP for the person who will actually run it.
How to de-risk the transfer
Plan three plant trials, not one. Document every parameter at each scale. Keep a retained sample from every stage for sensory comparison. And treat the first successful plant batch as the reference standard, replacing the lab sample in all subsequent comparisons.