This simple 9 page website discusses and explains the process of pateurisation, the equipment used and the need for the pasteurisation of milk.
The paper first defines the need for pasteurisation as being to protect public health and to manage the selflife of dairy products.
It then defines pasteurisation conditions and describes the processes and equipment required to run pasteurisation in a dairy. Heat recovery, pressure drops, holding tube design and instrumentation are discussed in some detail.
As mentioned in a previous post the University of Guelph has a strong reputation in Food Technology and has some very useful online information. Its worth following the link from the image and browsing around to see what other useful information you can find.
click image to visit GEA Process Engineering site
In falling film evaporators the liquid product (A) usually enters the evaporator at the head (1) of the evaporator. In the head the product is evenly distributed into the heating tubes. A thin film enters the heating tube are it flows downwards at boiling temperature and is partially evaporated. In most cases steam (D) is used for heating the evaporator. The product and the vapor both flow downwards in a parallel flow. This gravity-induced downward movement is increasingly augmented by the co-current vapor flow. The separation of the concentrated product (C) form its vapor (B) is undergoing in the lower part of the heat exchanger (3) and the separator (5).
This nice and simple explanation of how gravity filling works is one of the many useful pieces of information on the APACKS website.
from: APACKS (click image for full story online)
This shows clearly how the fill volume is controlled by the very simple tactic of stopping the escape of air from above the filling liquid. The gravity in the name of the filler refers to the force that causes the liquid to flow, namely gravity rather than piston, auger or positive displacement.
Have a look at the site and see the different types of filling equipment available.
Here is an interesting online spreadsheet.
from: Hyfoma (click image to interact with spreadsheet online)
As well as allowing the user to remove the instrumentation of text for clarrity
the instruments shown are linked through to a brief description of the instrument and its principle of operation.
Interesting from the Food Processing and the INTERNET information viewpoint!
Aseptically packaged milk and juice has probably had the biggest impact of any technology in the beverages industry in the last 50 years.
One of the packaging machines of the Tetrapak, the company that started the trend by fabricating an aseptic machine, is pictured below.
from: TetraPak (click image for full story online)
This page actually contains an interactive diagram of the filler where you are able to look at key aspects of the machine and its design.
A nice way to view these multi million dollar machines!
This is a short 10 page note from The National Sustainable Agriculture Information Service . It summarises the various drying technologies applicable to food drying in a concise manner, supporting this with some cost information.
from: ATTRA (click image for full story online)
It then focusses on the potential of drying as a value addition process on the farm before ending with a lot of information and supplier links.
Here is a nice note and flow diagram that guides the user in things they should consider when choosing a packaging system.
Falling Film Evaporators are designed for the production of concentrates from heat sensitive liquids.
The text on the above image from a Wiegand brochure reads:
FALLING FILM EVAPORATORS
Vertical shell-and-tube heat exchanger, with laterally or con- centrically arranged centrifugal separator.
The liquid to be concentrated is supplied to the top of the heating tubes and distributed in such a way as to flow down the inside of the tube walls as a thin film. The liquid film starts to boil due to the external heating of the tubes and is partially evaporated as a result. The downward flow, caused initially by gravity, is enhanced by the parallel, downward flow of the vapour formed. Residual film liquid and vapour is separated in the lower part of the calandria and in the downstream centrifugal droplet separator. It is essential that the entire film heating surface, es- pecially in the lower regions, be evenly and sufficiently wetted with liquid. Where this is not the case, dry spots will result