Tetra Pak tank 'eliminates' post-processing ESL milk bacteria growth
Unveiled by Tetra Pak earlier this week, the Tetra Alsafe was designed to reduce the threat of microbiological growth that can occur when the temperature of stationary ESL milk increases.
The fully-automated aseptic tank system allows processed ESL milk to circulate under refrigerated conditions in the event of an unplanned stoppage.
Using steam, the unit is sterilized at a minimum temperature of 125 degrees Celsius for 30 minutes.
It is then cooled to a temperature of between four and six degrees Celsius by water circulating through the cooling jacket.
“It is between these temperatures that it is recommended to keep the product to avoid the microbiological growth," Carin Cronstrom, chilled and fermented solutions manager, Tetra Pak Dairy and Beverage Systems, told DairyReporter.com.
Temperature control "essential"
ESL milk, which boasts a shelf life of up to 30 days, is produced using a combination of microbial filtration and heat treatment. Unlike UHT milk, which can lose some taste during heat treatment, ESL milk has virtually the same taste as fresh milk.
Despite the advanced processing techniques involved, ESL milk products require “careful handling” as microbiological flora can grow between the processing and packaging stages.
"It is the thermoduric microorganisms, the ones surviving pasteurization, and the psychrotrophic bacteria, the ones which grow at low temperature, that are responsible for the product failure due to microbiological growth in chilled pasteurized milk.”
“A small increase in temperature will cause a rapid increase in the growth rate of these microorganisms. Control of the temperature is therefore essential.”
Global demand
ESL milk products, which typically sell at a premium, are gaining popularity among consumers worldwide.
Tetra Pak expects interest in its Tetra Alsafe technology to correspond with this increasing global demand.
“There is growing demand for high quality extended shelf life products globally," said Cronstrom.
"Tetra Pak’s target markets all typically have a chilled distribution chain, for example in Europe, Russia, North America, Japan, Australia and New Zealand. Certain areas of South East Asia are also increasingly consuming more and more high quality chilled extended shelf life products.”
