This application note focuses on the benefits of the Ebro EBI 12 Wireless Temperature Data Loggers in ensuring the adequacy of the Cook Chill Processing Method in the Food Industry, and to give us a good indication that those microorganisms that were inactivated by the process are not given any conditions for re-growth.
- Application Note
While commercial Food preservation in general has been known to serve the main purpose of slowing down the rate of food deterioration or spoilage and ensuring food safety, the quality and sensory attributes of the food product must also not be compromised.
With hundreds and thousands of different food brands available in the market, your product needs to be fresh, with just the desired texture, flavorsome and delectable when compared to other competing brands.
Therefore, tests and measurements in the whole process are necessary to optimize the food preservation process and provide the food product just the right ‘microbial kill’.
Most of these measurements such as Heat Distribution Tests (HDT) and Heat Penetration Tests (HPT) in food processing are in Retorts where low-acid food products are made to become shelf-stable in hermetically-sealed containers. The most popular retorted commercial products are still those products in cans and in pouches.
Retortable Pouches and Cans Processed in Retort Vessels
This has changed dramatically in recent years because of the consumers’ desire for better-tasting, fresher and healthier food products and therefore requires these food products not to be treated with extremely high temperatures to addressing food safety. This made the Low-Acid Pasteurization Method and Cook- Chill Processing Method one of the best options and at the same time the most economical yet effective processing alternative.
This process involves lower temperatures to effect microbial inactivation but requires continuous control to extend shelf life and keeping food safety as its main objective without compromising on quality, taste and other fresh-food goodness attributes. However, as this process is the least to address the near absolute destruction of microorganisms, it should therefore be a highly-controlled process that requires in-situ accurate measurements and a well-documented thermal process validation. This means continuous measurements from cooking, packing, chilling, food storage and distribution in accordance to acceptable standards and guidelines such as SOPs, HACCP and other Food Safety guidelines.
Aside from the conventional Sous-Vide or Cook-Chill processes utilized by the food service or catering industry, where foods are fully-cooked, vacuum-packed, blast frozen and chilled so they can be served with a simple reheating; other food products are even hardly-cooked such as heat-sensitive fruit beverages and heat-sensitive seafood products such as crab meat.
Low Acid Food Products
The photos above are Low-Acid Food products and the microorganism of concern will always be the most heat resistant spore-forming clostridium botulinum and generally destroyed by a sterilization process at 121.0ºC. But doing so will damage the quality attributes and sensory properties of the heat-sensitive food products.
Cook-Chill Methods similarly with the other Pasteurization Methods will not allow ‘cook’ temperatures at more than 95.0ºC. Crab Meat for instance, considering its exquisite taste and naturally white colour, as much as possible must not be cooked over 90.0ºC.
Following strict guidelines & codes of practice, for instance from the Codex Alimentarius for Pasteurized crab meat – the crab meat in their packaging (cans, plastic tubs, bottles) are pasteurized in the hot water tank with temperatures from 85.0ºC - 88.0ºC for about 120 minutes or so until the process is able to provide the products a Po-value of < 31.0mins then immediately cooled in a chilled tank until the product temperatures are lowered down to below 3.0ºC.
Other food products that undergo cook-chill processing method are quickly loaded into a blast freezer before they are stored. An improved system is a spiral blast freezer unit for a better yield and consistent freezing condition.
This application note focuses on the benefits of the Ebro EBI 12 Wireless Temperature Data Loggers in ensuring the adequacy of this processing method and to give us a good indication that those microorganisms that were inactivated by the process are not given any conditions for re-growth.
This is best illustrated as follows:
The first two phases of this method of Pasteurization or Cook-Chill are considered the most critical where a required lethality value represented by Pu or Po-values (sometimes Co-values) as values of significance determined for each types of Food products must be achieved.
(Codex Guidelines and Codes of Practice)
These required lethality values, in their least number, must be provided to the products by the process with examples shown in the PDF version of this application note.
(Book of Manfred Eisner; N.F.P.A, N.C.A., Raichert)
Temperature references, lethal rates or kinetic factor (z-values) are established and herein used as constants corresponding to your target microorganisms. These are further used to calculate your process as a combination of time and temperature resulting to the acceptable lethality values as listed in the table.
Temperature Data Acquisition needs to be performed during the cook-chill or pasteurization process and in a predetermined sampling interval. These captured temperatures against time data are then used to calculate the Pu/Po-values/ Co-values using the formula as follows:
Ebro (a Xylem brand) offers a complete validation package for this processing method and allows the Food Quality Management and Control Team the fast and reliable implementation of the Process Adequacy Determination procedures.
With the EBI 12’s wide measuring range, it can remain in the food container for continuous measurements – from the cooking machinery to the blast freezers or chiller units.
With the EBI 12’s state-of-the-art and robust engineering design, plus the accuracy from the PT1000 sensor elements that will not drift through extreme changes in temperatures, you can be assured of maintained accuracy in measurements throughout the entire duration of your cook-chill process.
The Winlog.Pro Software further reinforces your Process Adequacy measurements with the automatic Po/Pu-value and Fo-value calculations with a few clicks as shown below: