To know if cleaning was good you must control it.
I chose to do this by examining the waste water. I take a sample of the last rinsing water. From this water I filtrate three times 100ml over a membrane. Then I add the appropriate medium. After that the plates are incubated at the right temperature during a specific period. When time is up, plates are inspected. One can see this in the figure below.
This technique takes several days before result. To become a quick indication of the cleaning I also take ATP swabs in the tank. In the next figure you see how this is done
Two weeks ago I started to examine whether there are still organic compounds in the last rinsing water. Do you think this is useful? Or maybe not in all cases? Should I do some other extra tests?
Cleaning in Place or CIP is a technique by which one can clean tanks and lines without dismantling the equipment. With CIP the cleaning can be done faster and with detergents at higher concentration . The CIP is computer controlled by a PLC program. I won’t explain how the program works but only what the output is.
Cleaning is done in several steps. A complete cleaning program contains following steps.
– Flush with water to remove the largest waste
– Cleaning with leach
– Flush with water to remove all leach
– Cleaning with acid
– Flush with water to remove all acid
– Disinfect with peracetic acid and hydrogen peroxide
– Flush with water to remove all products that are left in the tank
In this movie one can clearly see how CIP is done:
The company where I’m doing my research makes mainly fruitjuices, cidre, perry and beverages with high alcohol percentage (>15%).
What do you think I should take into account for optimal cleaning? What are the potential hazards of insufficient cleaning?
Unfortunately the subject of my master’s thesis has changed. The new subject of my blog will be cleaning of tanks that are used to make beverage. Cleaning contributes to continuous quality. There are a lot of ways to clean and disinfect a tank. In the company I’m doing my research tanks are cleaned by a cleaning in place system or CIP.
CIP is an easy technique because all the equipment can stay at its place. I will discuss this system in another post.
The purpose of my thesis will be to compose a rinsing array in which one can easily see what kind of rinsing step is needed after production of one beverage before the next.
Pasteurization is a heat treatment. While pasteurization the beverages are kept on a fixed temperature during a fixed time. The temperature is below 100°C, otherwise it’s called sterilization. Pasteurization is used to kill micro organisms present in the juices. By killing them the shelf life becomes longer. A typical graph of a pasteurization process can be seen in the figure.
In practice the temperature varies from the ideal one. To know how long the beverage has to stay at which temperature one can do some calculations. These values vary from micro organism to micro organism.
In my next posts I’ll discuss which are the micro organisms that occur most often in fruit juices and the danger they are for humans. Also influence on taste and view will be discussed later. I’ll give an overview of the different types of pasteurization and other techniques that can be used to enlarge the shelf life of fruit juices.