Among all the processes, Fritz process is commonly used. The machine working on the principle of Fritz process, consists of the following four sections.
a) Primary churning section
b) Secondary churning or separating section
c) Buttermilk drainage section
d) Salting and working section
a) Primary churning section
b) Secondary churning or separating section
c) Buttermilk drainage section
d) Salting and working section
 |
| Continuous butter making machine |
Cream flows from the cream storage tank via a balance tank and is fed by means of a positive displacement pump to the rear of the primary churning section. Control of flow rate is essential to ensure proper churning, drainage of buttermilk, working and flow of butter to the packaging machine. The churning section consists of a horizontal cylinder with a rapidly rotating beater. The gap between the cylinder wall and the beater is only a few millimeters. The beater speed can be varied in the range of 0-1400 rpm. The residence time for cream in the section is only 1- 2 sec.In this very short time, small butter granules are formed but are not allowed to join together to become bigger. The beater speed is adjusted accurately to yield butter grains of correct size. If the size is too small it causes difficulty in drainage of buttermilk. Fat loss in butter milk increases. On the other hand, if the size is too big it will entrap more buttermilk resulting in unsatisfactory drainage of buttermilk.
The speed of beater is influenced by the following factors:
i) Flow rate of cream,
ii) Fat content of cream,
iii) Temperature of cream,
iv) Pre-treatment of cream, and
v) Viscosity of cream.
In the separating section, the butter grains receive a second churning effect to adjust their size for proper drainage of buttermilk with minimum fat loss. The outlet portion at the end of this section is fitted with a fine mess screen through which the buttermilk is removed. A washing device is also provided at the end of the section to facilitate washing of the grains.After formation of proper grains of butter and initial draining of buttermilk, the grains pass into the working section. This section consists of two separate sub-sections in a Pasilac machine. This section is inclined and fitted with augers, which propel the grains forward, also squeeze some buttermilk and allow it to drain. At the end of this section there is a series of perforated plates and mixing vanes followed by a flow- regulating gate. The degree of opening of gate will affect the back-pressure on butter and thus affect the drainage of buttermilk from the butter.
In addition the speed of the auger will either increase or decrease the residence time, which will affect buttermilk drainage.In the salting section salt-water slurry (50:50) is injected between the first and second working plates in the section. A positive displacement pump is used to deliver accurate quantity of the salt slurry to the butter. Butter is then passed to a vacuum chamber where its air content is reduced from 6% to 1% and dropped onto augers in the second working section where it is pushed forward by the augers through another series of perforated plate. No buttermilk is separated in this second working section. After the final working, butter is pumped to the packaging machine by a positive pump. The entire system of butter manufacture can be computer controlled. In large manufacturing plants, butter is stored in a butter silo before packaging just to maintain some buffer stock. From the silo, it is pumped to the packaging system with the help of another positive pump.
The speed of beater is influenced by the following factors:
i) Flow rate of cream,
ii) Fat content of cream,
iii) Temperature of cream,
iv) Pre-treatment of cream, and
v) Viscosity of cream.
In the separating section, the butter grains receive a second churning effect to adjust their size for proper drainage of buttermilk with minimum fat loss. The outlet portion at the end of this section is fitted with a fine mess screen through which the buttermilk is removed. A washing device is also provided at the end of the section to facilitate washing of the grains.After formation of proper grains of butter and initial draining of buttermilk, the grains pass into the working section. This section consists of two separate sub-sections in a Pasilac machine. This section is inclined and fitted with augers, which propel the grains forward, also squeeze some buttermilk and allow it to drain. At the end of this section there is a series of perforated plates and mixing vanes followed by a flow- regulating gate. The degree of opening of gate will affect the back-pressure on butter and thus affect the drainage of buttermilk from the butter.
In addition the speed of the auger will either increase or decrease the residence time, which will affect buttermilk drainage.In the salting section salt-water slurry (50:50) is injected between the first and second working plates in the section. A positive displacement pump is used to deliver accurate quantity of the salt slurry to the butter. Butter is then passed to a vacuum chamber where its air content is reduced from 6% to 1% and dropped onto augers in the second working section where it is pushed forward by the augers through another series of perforated plate. No buttermilk is separated in this second working section. After the final working, butter is pumped to the packaging machine by a positive pump. The entire system of butter manufacture can be computer controlled. In large manufacturing plants, butter is stored in a butter silo before packaging just to maintain some buffer stock. From the silo, it is pumped to the packaging system with the help of another positive pump.
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.