-
Ghee may be defined as clarified butterfat prepared chiefly from cow or buffalo milk. (To clarify means ‘to make clear’ a liquid or something liquefied, by removing unwanted solid matter or impurities.)
-
According to the PFA (1976), ghee is the pure clarified fat derived solely from milk or from desi (cooking) butter or from cream to which no coloring matter is added.
Chemical composition of ghee
|
Characteristics
|
Requirements
|
|
Cow
|
Buffalo
|
|
Milk fat
|
99 to 99.5 per cent
|
|
Moisture
|
Not more than 0.5 per cent
|
|
Unsaponifiable matter
|
|
Carotene ( m g/g.)
|
3.2-7.4
|
-
|
|
Vit.A (I.U./g)
|
19-34
|
17-38
|
|
Tocopherol ( m g/g.)
|
26-48
|
18-37
|
|
Free fatty acids (% oleic)
|
Max. 2.8 (agmark)
|
|
Charred casein, salts of copper and iron, etc.,
|
Traces
|
Physico-chemical constants
Ghee is characterized by certain physico-chemical properties, which show some natural variations depending on such factors as, method of manufacture, age and condition of the sample, species, breed, individuality and animals stage of lactation, season of the year, region of the country, feed of the animal etc.,Some of the important analytical constants or standards of mixed ghee produced under standard conditions are given below:
(Cotton tract refers to the areas in the states where cottonseeds are extensively fed to the cattle and so notified by the state government concerned.)
-
Ghee is defined as clarified butter fat with a strong characteristic flavor prepared by heating makkhan, in an open pan, to about 110-120ºC till all the moisture is evaporated and the characteristic flavor develops. It can be compared to butter oil. Butter oil is the western counterpart of ghee.
Origin
-
Ghee originated in India much before recorded history and the name originates from the sanskrit word meaning “bright”. The Vedas contain numerous references to ghee.
Method of Preparation
-
More than 90 percent of ghee is produced by the traditional method from desi butter or makkhan and then converting it into ghee.
-
Makkhan, which is produced by churning the curd, is heated in a metallic vessel and stirred over a low fire to evaporate the moisture.
-
When practically all the moisture is removed, further heating is stopped and the vessel is removed from the fire. After the residue has settled down on cooling, the clear fat is decanted into suitable containers a ghee.
|
Tests
|
All India Regional
|
|
Winter
|
Summer
|
|
Baudouin
|
Negative
|
Negative
|
|
Phytosterol acetate
|
Negative
|
Negative
|
|
B.R.reading (40ºc) [40.0-43.0]
|
41.5-44.0
|
42.5 - 45
|
|
R.M.Value [28.0]
|
Not less than 23.0
|
Not less than 21.0
|
|
P. Value [1.0-2.0]
|
0.5-1.20
|
0.5-1.0
|
|
Moisture (%)
|
not more than 0.3
|
not more than 0.3
|
|
FFA (% oleic)
|
Special-grade Agmark Red label not more than 1.4
General-Grade Agmark Green label not more than 2.
|
-
Percentage of ghee residue = (Weight of ghee residue x 100) / Weight of butter
-
Percentage of ghee obtained = (Weight of ghee x 100) / Weight of fat in butter
-
Weight of fat in butter = 80 x weight of butter
Methods of preparation
Ghee can be prepared by various methods, which are as follows:
Desi Method
Fresh or accumulated over a few days, makkhan (butter) is taken in a suitable open mud-pot or metallic vessel, and heated and stirred on a low fire to drive out the moisture. When practically all the moisture has been removed, a stage judged by experience, further heating is stopped and the vessel removed from the fire. On cooling, when the residue has settled down, the clear fat is decanted into suitable containers.
Merits
Demerits
-
Extremelysmall scale in operation, problems in collecting and marketing
-
Lowkeeping quality and vitamin content.
Creamery butter method
-
A standard method, where unsalted creamery butter is used. Butter is heated in an ghee boiler consisting of a steel jacketed pan with a stirrer, with steam supply and control valves. The butter mass, is cut into small pieces and heated on low heat and carefully stirred. Later after complete melting, the steam pressure is raised to bring the liquid mass to boil at a temperature of90ºC. The contents are constantly agitated throughout the process of conversion of butter into ghee, to prevent scorching. The scum, gathering on the top is periodically removed, until there is profuse effervescence, followed by crackling sound, initially. When all the moisture have been driven out, the temperature of the liquid shoots up suddenly and end point is indicated by the appearance of effervescence for the second time together with browning of the curd particles. At this stage, characteristic ghee flavor emanates and the temperature now will be around 110-120ºC . Heating is then stopped, and after cooling and sedimentation, the ghee is filtered through a muslin cloth and goes for granulation and packaging.
Merits
Pre-stratification method
-
The two above mentioned practices of ghee making has the disadvantage of poor quality of the finished product characterized by an over-heated and smoky flavour, along with high acidity, making it greasy and with reduced shelf life.Hence research work has led to the evolving of a newer method/technique, which yields a higher grade product at lower cost, known as the pre-stratification process.
-
The basic principle of this method is that, when butter is left undisturbed 80-85ºCfor 15 to 30 minutes, it stratifies, i.e., separates into 3 distinct layers, viz., a top layer of floating denatured particles of curd, a middle layer of fat, and a bottom layer of buttermilk. This separation is called pre-stratification. The bottom layer of buttermilk contains 60-70 percent of solids-not-fat and also over 80 per cent of the moisture originally present in butter. The buttermilk is removed mechanically without disturbing the top and middle layers. After wards, the temperature of the remaining two upper layers (of denatured curd and fat) is raised to the usual clarifying temperature of 110-120ºC.
Merits
Direct-cream method
-
Here,the cream obtained by normal separation of milk is heated in the same ghee boiler described for the creamery-butter method and the procedure for heating and moisture removal, final temperature of clarification, cooling and sedimentation, granulation and packaging also remain the same.
Merits
Demerits
Continuous method
Objects
Advantages
-
Large scale handling
-
Utilization of machines for a large number of operations
-
Uniform demand on services
-
High fat recovery
-
Possibility of in-place-cleaning (IPC)
-
No stirring, no scrapping and no laborious effort on the part of the ghee operators required.
Final temperature of clarification
Cooling and granulation (crystallization)
-
Granularity in ghee is considered as an important criterion of quality and even purity. Granular form of ghee is assumed primarily to certain content of glycerides of high-melting saturated fatty acids, esp.palmitic and stearic acid. In this regard the buffalo ghee, which is more saturated, crystallizes more effectively than cow ghee. It has been observed that heating ghee to 60-100ºC, followed by rapid cooling, yields small grains inghee; however, if the ghee is held for crystallization at a temperature about1ºC above the melting point of ghee (cow ghee–29ºC; buffalo–31ºC), a large number of big grains result. Cold storage of ghee should be avoided, as it leads to a loss of granularity and the product develops a waxy consistency,when stored.
Renovation of Ghee
This refers to the market practice of attempting to improve the old and rancid ghee, so as to make it marketable as a product of secondary quality.
Some of the methods employed for the renovation of ghee include
-
Re-heating inferior ghee with curd, betel leaves, etc., and subsequently filtering it;
-
Adding a yellow substance, such saffron,annatto, turmeric juice, etc to make it as cow ghee
-
Blending an inferior ghee with a superior quality product.
Neutralizing high-acid ghee
-
Market ghee sometimes develops large quantities of free fatty acid (oleic), which results from faulty methods of preparation and storage. This produces harmful effects in the body system. This is tackled by the process neutralization. In one, the neutralizer used is sodium hydroxide, and other is lime. Lime is more preferable than sodium hydroxide. First the high acid ghee to be refined, is heated to 60-70ºC, and finely ground, good quality lime(shell-lime), powdered to 60 mesh is then sprinkled on the surface @ 3 % of ghee. The temperature is quickly raised to108ºC with gentle stirring and mass is cooled and filtered at 60ºC.
Antioxidants
-
Lipidoxidation is a chain reaction involving initiation, propagation and termination stages. The unsaturated fatty acids are oxidized to form odorless, tasteless hydro peroxides, which further degrade to yield carbonyls and other compounds,which give out the characteristic unagreeable oxidised flavour. The various factors which affect oxidation include, oxygen concentration, light intensity, contact with metals etc., Anti-oxidants are substances used to inhibit the progress of lipid oxidation, and may be either natural (e.g., Tocopherols, carotene,) or synthetic substances(Butylated hydroxy anisole, Butylated hydroxy toluene, Hydroquinone, gallicacid esters etc.,) Metal-chelating agents, such as citric acid and phosphoricacid, EDTA act in conjunction with anti-oxidants and inhibit fat oxidation.
-
Keeping quality of Ghee can be extended by the addition of antioxidants. Under the PFA Rules (1976), BHA at not exceeding 0.02 per cent can be added. Naturally, betel leaves and curry leaves are added while ghee making at 1 per cent level, which gives good flavour to ghee as well as it acts as antioxidant.
The AGMARK ghee-grading scheme
Literally Agmark is an insignia - AG for “agricultural” and MARK for ‘marketing ’ with a view to develop the orderly marketing of agricultural produce on all India basis, the Indian legislature had passed the agricultural produce (grading and marketing) act 1937, this act provides for the grading of ghee on a voluntary basis.
The Agmark grading scheme was introduced mainly to achieve the following objectives.
-
To assure the consumer a produce of pre-tested quality and purity.
-
To enable manufacturers of a high-grade product to obtain better returns.
-
To develop an orderly marketing of the commodities by eliminating malpractices when transferring them from the producer to the consumer.
Defects in ghee, their causes and prevention
|
Name of the defect
|
Causes
|
Prevention
|
|
Flavour
Smoky
|
Smoky fire used for boiling milk or converting makkhan into ghee in desi method.
|
Using non smoky fire for boiling milk or converting makkhan in to ghee in desi method
|
|
Overcooked /burnt
|
Excessive high temperature of clarification of ghee
|
Optimum temperature of clarification of ghee
|
|
Undercooked
|
Excessive low temperature of clarification
|
Optimum temperature of clarification of ghee.
|
|
Rancid
|
Fat hydrolysis due to lipase action in milk / cream / curd / butter/kachcha ghee.
|
Inactivation of lipase by proper pasteurization heating of milk cream etc.,
Using optimum clarification of the
Packaging in small containers for retail sale.
|
|
Oxidized/oily/Metallic
|
Fat oxidation due to direct contact of milk curd/cream/butter/ghee with copper or iron exposure of this product to sunlight etc.
|
Storage of milk curd / scream / butter / ghee in properly tinned or aluminum alloy /stainless steel vessels.
Filling ghee up to the brim so as to avoid any head space air
Avoiding storage of ghee at high temperature
Avoiding use salted butter from ghee making avoiding long storage of ghee
Storage of ghee in opaque containers.
|
|
Texture
Greasy
|
Rapid cooling of hot ghee after clarification.
Subjecting ghee to further heating and cooling treatments after preparation.
|
Slow cooling of hot ghee after clarification
Avoiding further heating and cooling of ghee after preparation.
|
|
Colour
Burnt
|
Excessively high temperature of clarification of ghee.
|
Optimum temperature of clarification of ghee.
|
|
Sediment
High
|
Incorrect straining of ghee
|
Correct straining of ghee.
|
|
Burnt
|
Excessively high temperature of clarification of ghee.
|
Optimum temperature of clarification.
|
Uses of Ghee
Ghee residue
This refers to the charred light to dark brown residue which is obtained on the cloth strainer after the ghee, prepared by different methods, is filtered. It is by-product of the ghee industry. Essentially it contains heat-denatured milk-proteins, caramelized lactose and varying proportions of entrapped fat,besides some minerals and water.
|
Type of Residue
|
Chemical composition
|
Ave.Yield (kg)
(per 100 Kg) Butter / Cream (kg)
|
|
Water
|
Fat
|
Protein
|
Lactose
|
Ash
|
|
From Desi Butter
|
|
Cow
Buffalo
|
14.4
|
32.4
|
36
|
12
|
5.2
|
1.6
|
|
13.4
|
33.4
|
32.8
|
15.4
|
5.2
|
1.6
|
Ghee residue is a rich source of milk fat,proteins and minerals. Methods of recovery of ghee-residue includes, centrifugal and pressure techniques.
Uses
|