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The matter changes from liquid to solid. This is not necessarily a chemical change (reaction) but a physical change in state.
However, once the cream has been turned into butter it cannot be returned to its cream state.
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Is churning cream to make butter,is it a physical or chemical change.?
The answer is both. What? : )
In summary...
Intro:The chemical changes are subtle and consistes more of what are clalled "conformation" of the chmical in the case of butter, fats. In order for these transformation to take place physical aggitation is required. Also temperature has a signiivcant effect on the fat compositions.
Hold on to your hat.
Basics:
Edible fats of vegetable, marine or animal origin all form three main types of crystal, the alpha, beta, and beta-prime forms. The alpha form is the least stable and existence in this form is usually transitory. The alpha form consists of fragile, translucent crystals 5 micometers in length. Thr bata-prime form consists of tiny, delicate crystals 1 micrometers and the beta form of relatively large and coarse crystals, which average 25-50 micrometers (um) in length.
Physical & Chemical Changes
Liquid fats and triacylglycerols cooled without agitation tend initially to form alpha crystals. Further cooling of the alpha form leads to tighter chain packing and a gradual transition to the beta form. Cooling with agitation. however, favors formation of the beta-prime form.
Milk fat is of the beta-prime form, as is beef tallow and whale oil. Pork lard, however, is of the beta type. Of vegetable fats commonly used in mararines and spreads, coconut, oilve, peanut, soy bean and sunflower oil are of the beta type, while rapeseed, cottonseed and palm oil are beta-prime.
Beta-prime crystals are desirable for butter, margarine and spreads and, in the latter two cases, a serious defect 'graininess' may result from the formation of large coarse beta-type crystals.
Physical and chemical modification of fat:
(a) Hydrogenation involves a reduction of the degree of unsaturation by addition of hydrogen to double bonds in the fatty acid chains.
Fat is usually hydrogenated by a batch process which involves mixing the oil with nuckel or another suitable catalyst and heating to 140-225 C under hydrogen at pressures up to 60 psi. Agitation is necessary to completely dissolve the oxygen, to ensure uniform contact between oil and catalyst, and to dissipate the heat of reaction.
In addition to saturation of some double bonds, hydrogenation may also lead to relocation and/or transformation from cis to trans configuration, the isomers being commonly referred to as iso acids.
(b) Inter-esterification is a chemical process by which the distridution of fatty acids among the tricylglycerols is altered. This results in a change from the unique fatty acid distribution patterns of many fats to a random distribution with a resultant change in the physical properties. Inter-esterification of milk fat results in an increase in the solid fat content at 35 C, which produces a 'tallowy' mouth-feel. Inter-esterification produces better nutritional and spreading properties of milk fat in butter.
(c) Fractionation preserves characteristic flavor of the milk fat.
Structure
Butter, maragarine and high-fat spreads exists as stable water in oil emulsions, the aqueous phase is relatively evenly distributed through the product and water droplets are, ideally, in the size range 2-4 um.
The fat phase of butter, margarine, and spreads consists of a crystal matrix of solid fat which retains the liquid oil in suspension. In addition churned products such as butter and some types of spred contain some globular fat which limits the tendency of the higher meltinf point crystals to form an over thick shelled type, and also contributes to the mouth-feel and spreadability by behaving like microscopic ball bearings.
So milk fat is treated in such a way as to allow it to form a fatty-oil-liquid mattrix. The alterations of the milk fats give them the characterisic melting point, mouth-feel, and flavor we are used to in butter, margarine, and spreads.
Source(s):
see profile
Milk & Milk Products A. Varnam and J. Sutherland
ISBN 0-412-45730-x
What else can I help you with?
Is the burning of leaves or melting of butter a physical reaction?
The burning of leaves is a chemical reaction. The way we can tell is because after the leaves are burned, they cannot go back to the way they were. Butter melting is a physical reaction because it does not change the molecules, and the butter has the ability to go back to it's original state.
When Butter is melting is it a physical or chemical change?
Melting of butter is a physical change.
Is melting butter chemical or physical change?
Melting butter is a physical change because it involves a phase change from a solid to a liquid without altering the chemical composition of the butter.
Is a melting butter a physical change or a chemical change?
Melting butter is a physical change because the butter retains its chemical composition while transitioning from a solid to a liquid state.
When melted butter soldifies in the refrigerator is that physical or chemical change?
When melted butter solidifies in the refrigerator, it is a physical change. The butter is simply changing from a liquid state to a solid state due to the decrease in temperature, with no change in its chemical composition.
Was heated butter in a frying pan a chemical reaction?
No, heating butter in a frying pan is a physical change, not a chemical reaction. The butter changes from solid to liquid due to the increase in temperature, but the molecules of butter themselves remain the same.
Is the burning of leaves or melting of butter a physical reaction?
The burning of leaves is a chemical reaction. The way we can tell is because after the leaves are burned, they cannot go back to the way they were. Butter melting is a physical reaction because it does not change the molecules, and the butter has the ability to go back to it's original state.
Are butter biscuits a chemical change?
It is not chemical change ,it is a physical change
What is an example of a physical change in baking?
both, because the ingredients are undergoing both physical and chemical changes such as: Butter melting= physical change Egg whites hardening= chemical change both, because the ingredients are undergoing both physical and chemical changes such as: Butter melting= physical change Egg whites hardening= chemical change
Spreading butter on toast is a physical change?
Physical. It is still butter. It is still just a piece of bread. But now it is butter on a piece of bread with a bite out of it. The bread/butter is not chemically changing to form a TOTALLY new substance. For instance, when you melt butter its no longer a solid its now a liquid. Looks different, the temperature is different, and it may even taste diifferent but its still butter. But if you were to take sugar and dissolve it in water it becomes a totally different substance.
Is Butter melting in a pan physical or chemical change?
Melting butter in a pan is a physical change. It involves a change in state from solid to liquid without altering the chemical composition of the butter.
When Butter is melting is it a physical or chemical change?
Melting of butter is a physical change.
Is melting butter chemical or physical change?
Melting butter is a physical change because it involves a phase change from a solid to a liquid without altering the chemical composition of the butter.
Is butter melting on warm toast a chemical or physical property?
It is a physical property. A chemical property would involve the butter reacting to the toast, but the butter is actually reacting to the heat from the toast. The butter would melt against any surface hot enough, where as butter would not melt on cold toast. Hence, the reaction to heat makes it a physical property. (A relatively easy way to remember is that physical properties deal with the transfer of physical energy or force such as heat, inertia, etc. Chemical properties occur when two material substances trade molecules or electrons.)
Is making butter a physical or chemical change?
Physical.
Is a melting butter a physical change or a chemical change?
Melting butter is a physical change because the butter retains its chemical composition while transitioning from a solid to a liquid state.
Is butter melting on toast a chemical or a physical change?
it is a physical change
