By Isaac Fletcher, contributing writer, Food Online
A new pasteurization process for juice reduces energy costs up to 19 percent by dropping processing temperatures by 15 degrees Celsius
Recent research indicates that juice may currently be over pasteurized during production, leading to unnecessary waste of energy, money, and time. However, by lowering the temperature used in pasteurization, the process can be altered to be more efficient while still maintaining standards of quality and taste.
The industry standard for pasteurizing juice is a two-step process, during which, heat treatment is used to make the product more stable for storage. The first step, primary pasteurization, is done as soon as possible after the juice is extracted at a temperature of 95 to 98 degrees Celsius for 10 to30 seconds. The purpose of this is to inactivate enzymes before the juice goes into bulk storage. The second step, secondary pasteurization, is done prior to filling the containers and its purpose is to destroy microorganisms that occur as contaminants after bulk storage. This pasteurization is carried out at 95 degrees Celsius for 15 seconds.
Research, however, has shown that for juices with a pH of 4.2 or less, 80degrees Celsius for 15 seconds is sufficient for the secondary pasteurization process. This reduction in required temperature has the potential for large cost savings related to energy consumption — the reduction from 95 degrees Celsius to 80 degrees Celsius, even with the same duration of 15 seconds, could reduce energy consumption by up to 19 percent.
Additionally, results from test with Valio Oy from 2013 have shown that the juice pasteurized at 80 degrees Celsius was not only commercially sterile, but also exhibited no signs of experiencing more vitamin C degradation than its counterparts pasteurized at 95 Celsius. Appearance and taste also remained consistent between the juices pasteurized at two different temperatures. With this new pasteurization process, companies can destroy microorganisms to ensure product safety and improve their bottom line while still delivering juice that meets the safety, nutrition, taste, and visual demands of its customers.