Dispatches: Campden BRI Snacks Technology Conference
PepsiCo: Validating the kill step in oats is a ‘complex’ task
PepsiCo, under its Quaker brand in particular, uses oats on a large scale – processing them in kilns that can take up to 18,000 tonnes at any one time.
For the past 18 months the company has been working on a set of methodologies to validate the kill step in the oat kiln process, testing salmonella in particular.
But Paul Young, senior process authority at PepsiCo Europe, said this had been no easy task because the validation step faced a number of challenges.
“It’s taken some engineering solutions and very challenging ideas,” he told attendees at Campden BRI’s Snacks Technology conference last week.
“You’re talking about 18 tonnes of material in one go with large processing vessels, physical constraints, uneven flow and varying residence times.”
Temperature profiling the key?
Young said monitoring temperature profiles would be extremely useful for oats and was commonplace for other materials like liquid.
However, he said measuring temperatures in low moisture foods was not so straightforward.
“With an 18 tonne kiln, sometimes you’ve just got to accept the temperature profiling data is not going to be there. It’s almost impossible to get the device through there – it would take me over a week to get it through and because of how the product moves, you’re not going to get clear data.”
But, he said advances in data logging technology meant PepsiCo was closer to achieving temperature logs in the kiln.
“Once you understand the temperature profile attached to the product, then you can use and modify the pilot kit to (validate the kill step). But until you understand all that, it’s very hard to do.”
Surrogate analysis also tough
Young said PepsiCo was working with surrogate organisms throughout the process to test for salmonella but this was also tougher than usual in an oat kiln.
“You have to ensure the introduction of the surrogate does not alter the standard process… We have to ensure the product flows how it would normally flow to get the best results. Then, how do we retrieve the samples? With oats, that’s been the hardest challenge – how do we get the surrogate out to do the micro-work on it?”
