LPT 311: Milk and Milk Products Technology (1+1)

Butter analysis

ANALYSIS OF BUTTER BY KHOMAN METHOD

• Apparatus required: Aluminum cup, glass stirrers, balance, hot plate and tongs.
• Chemical required: Petroleum ether

Procedure

• The weight of empty Aluminum cup with stirrer is taken and weighed as W1. Take about 10 grams of butter and weigh it accurately as W2.
• Place the cup with stirrer and contents on sand bath over a hot plate and heat the contents with constant stirring till all the moisture is driven off. Care should be taken not to char the contents. End point is the formation of golden brown particles of the residue.
• Remove the cup; wipe the bottom to remove the sand particles. Cool it in a desiccators and weigh it as W3. Add about 6-10 ml of petroleum ether. Stir well to dissolve the fat and allow it to stand for 2-3 minutes and decant the supernatant in the cup.
• Repeat the extraction with 10 ml of petroleum ether. Dry the cup in a sand bath and keep it in desiccators. The cup containing the curd and salt is weighed as W4.

Judging of butter

• Examine the packet of butter for the presence of molds and for neatness. Open the packet and immediately inhale and note the odour. Cut with spatula and note the firmness of the body. Examine the cut side for oozing of moisture and presence of water droplets and air packets. Examine for the uniform distribution of colour on the cut surface. About 1 gm of butter is put into he mouth and allowed to melt. Note the taste and odour. Quality of butter is graded according to score card ADSA grades.
• The characters (Flavour, body and texture, Colour, Salt, Package) and Maximum marks (45,25 15, 10 and 5 points, A for 92 Point, B for 90 points and C for 89 Points and C for 89 Points.

Flavour

• Flavour gets maximum score and it is the main character in butter. It is a combination of taste and odour and odour being most important. The desired flavour in butter is described as sweet and nutty. Flavour is also described as fishy, rancid, curdy, cooked and yeasty, Butter can absorb odours and are desribed as unclean, fruity and etc.
• Body: this includes texture. It should be recently formed, close textured and waxy. There should not be excess moisture and should not stick on to hands.

Common defects

• Leaky and crumbly
• When butter is under worked crumbly butter results, if it is over worked. Greasy or sticky butter results. Cumbly butter also results if it contains higher amount of HMTG (High molting Tri glycerides). If butter is produced with prolonged churning and high temperature of wash water, it results in leaky butter.
• Colour : Natural colour of butter
• Cow – light yellow – golden yellow
• Buffalo – White.
• Distinct discolouration of surface occurs and it may be due to certain species of micro organisms. If colour is not uniformly distributed mottling results.
• Salt: if salt is added and not dissolved uniformly grittiness results. Salt is added to import a pleasant taste and to prolong keeping quality.
• Package: Packing material differs depending upon the usage and market demand, whatever be the packing material it should be hygienically clean and it should provide protection to contents from moisture, sunlight.