Centrifugation: Acetic Acid and Centrifuge Tube
Experiment 2: Centrifugation
Title
Centrifugation of fresh milk and Acetic Acid
Objective(s):
1. To separate coagulated milk from mixture of fresh milk and Acetic Acid by centrifugation
2. To determine the relationship of speed of centrifugation with the coagulation of milk which separate from mixture.
3. To study the process of centrifugation
Introduction
Centrifugation is a process which materials suspended in a liquid medium undergo separation or concentrate due to the effect of gravity. Particles with different density and masses are settled at different rates in a tube which are response to gravity. Centrifuge is an instrument which can spin carrier vessels at high rotation speed and very high centrifugal force to allow centrifugation. The centrifugal force generated is proportional to the rotation rate of the rotor and the distance between the rotor centre and the centrifuge tube.
There are three general classes of centrifuges: low speed, about 5000 rpm, high speed machine can up to about 25000 rpm and ultracentrifuges turn at up to1000000 rpm. Microcentrifuges are common in laboratories which generate between 10000 rpm and 13000 rpm and 0.5 or 1.5 mL of disposable plastic tubes is used. Rotors for a centrifuge are either fixed angles or swinging buckets. The aim is to separate the molecules through viscous media, then the swinging bucket is main choice. A component that may react with acetic acid (CH3COOH) is casein.
Materials
Centrifuge, Falcon tube (50mL), Centrifuge tubes (15mL), Microcentrifuge tubes (1.5mL), Micropipettes, blue tips (P-1000), Pipettes (10mL & 5mL), Plastic Pipette Pump, Fresh Milk, 50% Acetic Acid
Procedure
Add 10 ml of 50% of acetic acid was drawn by pipettes with plastic pipette pump and released into 50 ml Falcon tube. And, 5 ml of fresh milk was then drawn and released into falcon tube, where 10 ml of acetic acid contained. The first step was to mix the solution by gently inverting few times the falcon tube.
Title
Centrifugation of fresh milk and Acetic Acid
Objective(s):
1. To separate coagulated milk from mixture of fresh milk and Acetic Acid by centrifugation
2. To determine the relationship of speed of centrifugation with the coagulation of milk which separate from mixture.
3. To study the process of centrifugation
Introduction
Centrifugation is a process which materials suspended in a liquid medium undergo separation or concentrate due to the effect of gravity. Particles with different density and masses are settled at different rates in a tube which are response to gravity. Centrifuge is an instrument which can spin carrier vessels at high rotation speed and very high centrifugal force to allow centrifugation. The centrifugal force generated is proportional to the rotation rate of the rotor and the distance between the rotor centre and the centrifuge tube.
There are three general classes of centrifuges: low speed, about 5000 rpm, high speed machine can up to about 25000 rpm and ultracentrifuges turn at up to1000000 rpm. Microcentrifuges are common in laboratories which generate between 10000 rpm and 13000 rpm and 0.5 or 1.5 mL of disposable plastic tubes is used. Rotors for a centrifuge are either fixed angles or swinging buckets. The aim is to separate the molecules through viscous media, then the swinging bucket is main choice. A component that may react with acetic acid (CH3COOH) is casein.
Materials
Centrifuge, Falcon tube (50mL), Centrifuge tubes (15mL), Microcentrifuge tubes (1.5mL), Micropipettes, blue tips (P-1000), Pipettes (10mL & 5mL), Plastic Pipette Pump, Fresh Milk, 50% Acetic Acid
Procedure
Add 10 ml of 50% of acetic acid was drawn by pipettes with plastic pipette pump and released into 50 ml Falcon tube. And, 5 ml of fresh milk was then drawn and released into falcon tube, where 10 ml of acetic acid contained. The first step was to mix the solution by gently inverting few times the falcon tube.
References: 2. Spurlock. D, 2003, Isolation and Identification of Casein from Milk Course Notes 3. Basics of Centrifugation, 2006. [Online]. Available at: http://www.coleparmer.com/TechLibraryArticle/30 5. Biological Centrifugation (Spin biological), by D. Rickwood, J.M. Graham (2001). [Online]. Available at: http://www.coleparmer.com/TechLibraryArticle/910 [Accessed: 13 June 2013]