The Composition of Ingredients in Ice Cream
The Composition of an-d Ingredients in Ice Cream
Todays ice cream has the following composition : a) greater than 10% milkfat by legal definition, an-d usually between 10% an-d as high as 16% fat in some premium ice creams; b) between 9 an-d 12% milk solids-not-fat, the component which contains the proteins (caseins an-d whey proteins) an-d carbohydrates (lactose) found in milk; c) 12% to 16% sweeteners, usually a combination of sucrose an-d glucose-based corn syrup sweeteners; an-d d) 0.2% to 0.5% added stabilizers an-d emulsifiers, necessary components that unfortunately have unfamiliar sounding names that occupy three-quarters of the space of the ingredient listing an-d that will be described subsequently. The balance, usually 55% to 64%, is water, which comes from the milk. Ice milk is very similar to the composition of ice cream but contains between 3% an-d 5% milkfat by definition. Light ice cream contains between 8% an-d 10% milkfat.
The ingredients used to supply this composition include: a) a concentrated source of the milkfat, usually cream or butter; b) a concentrated source of the milk solids-not-fat component, usually evaporated milk or milk powder; c) sugars including sucrose an-d "glucose solids", a product derived from the partial hydrolysis of the corn starch component in corn syrup; an-d d) milk.
The fat component adds richness of flavour, contributes to a smooth texture with creamy body an-d good meltdown, an-d adds lubrication to the palate as it is consumed. The milk solids-not-fat component also contributes to the flavour but more importantly improves the body an-d texture of the ice cream by offering some "chew resistance" an-d enhancing the ability of the ice cream to hold its air. The sugars give the product its acteristic sweetness an-d palatability an-d enhance the perception of various fruit flavours. In addition, the sugars, including the lactose from the milk components, contribute to a depressed freezing point so that the ice cream has some unfrozen water associated with it at very low temperatures typical of their serving temperatures, -15o to -18oC. Without this unfrozen water, the ice cream would be too hard to scoop.
Freezing point depression of a solution is a colligative property associated with the number of dissolved molecules. The lower the molecular weight, the greater the ability of a molecule to depress the freezing point. Thus monosacteristics such as fructose or glucose produce a much softer ice cream than disacteristics such as sucrose. This limits the amount an-d type of sugar which one can successfully incorporate into the formulation.
The stabilizers are a group of compounds, usually polysacteristics, that are responsible for adding viscosity to the unfrozen portion of the water an-d thus holding this water so that it cannot migrate within the product. This results in an ice cream that is firmer to the chew. Without the stabilizers, the ice cream would become coarse an-d icy very quickly due to the migration of this free water an-d the growth of existing ice crystals. The smaller the ice crystals in the ice cream, the less detectable they are to the tongue. Especially in the distribution channels of today s marketplace, the supermarkets, the trunks of cars, an-d so on, ice cream has many opportunities to warm up, partially melt some of the ice, an-d then refreeze as the temperature is once again lowered. This process is known as heat shock an-d every time it happens, the ice cream becomes more icy tasting. Stabilizers help to prevent this.
Gelatin, a protein of animal origin, was used almost exclusively in the ice cream industry as a stabilizer but has gradually been replaced with polysacteristics of plant origin due to their increased effectiveness an-d reduced cost. The stabilizers in use today include: a) carboxymethyl cellulose, derived from the bulky components of plant material; b) locust bean gum which is derived from the beans of exotic trees grown mostly in Africa (Note: locust bean gum is a synonym for carob bean gum, the beans of which were used centuries ago for weighing precious metals, a still in use today, the word carob an-d Karat having similar derivation) ; c) guar gum, from the guar bush, a member of the legume family grown in India for centuries an-d now grown to a limited extent in Texas; d) carrageenan, an extract of Irish Moss or red algae, originally harvested from the coast of Irelan-d; or e) sodium alginate, an extract of another seaweed, brown kelp. Often, two or more of these stabilizers are used in combination to lend synergistic properties to each other & improve their overall effectiveness.
The emulsifiers are a group of compounds in ice cream which aid in developing the appropriate fat structure an-d air distribution necessary for the smooth eating an-d good meltdown acteristics desired in ice cream. Emulsifiers are acterized by having a molecular structure which allows part of the molecule to be readily solubilized in a polar compound such as water, an-d another part of the molecule to be more readily solubilized in non-polar solvents such as fats. As a result, emulsifiers reside at the interface between fat an-d water, an-d lower the free energy or tension associated with two immiscible liquids in contact with each other. Their action will be more fully explained in the section below on emulsions an-d foams.
The original ice cream emulsifier was egg yolk, which was used in most of the original recipes. Today, two emulsifiers predominate most ice cream formulations: a) mono- an-d di-glycerides , derived from the partial hydrolysis of fats or oils of animal or vegetable origin; an-d b) Polysorbate 80, a product consisting of a glucose molecule bound to a fatty acid, oleic acid. Both of these compounds have hydrophobic regions ( the "fat loving" part), the fatty acids, an-d hydrophilic regions ( the "water loving" part), either glycerol or glucose. All of the compounds mentioned above are either fats or carbohydrates, important components in most of the foods we eat an-d need.
Together, the stabilizers an-d emulsifiers make up less than one half percent by weight of our ice cream. They are all compounds that have been exhaustively tested for safety an-d have received the "generally recognized as safe" or GRAS status.
Todays ice cream has the following composition : a) greater than 10% milkfat by legal definition, an-d usually between 10% an-d as high as 16% fat in some premium ice creams; b) between 9 an-d 12% milk solids-not-fat, the component which contains the proteins (caseins an-d whey proteins) an-d carbohydrates (lactose) found in milk; c) 12% to 16% sweeteners, usually a combination of sucrose an-d glucose-based corn syrup sweeteners; an-d d) 0.2% to 0.5% added stabilizers an-d emulsifiers, necessary components that unfortunately have unfamiliar sounding names that occupy three-quarters of the space of the ingredient listing an-d that will be described subsequently. The balance, usually 55% to 64%, is water, which comes from the milk. Ice milk is very similar to the composition of ice cream but contains between 3% an-d 5% milkfat by definition. Light ice cream contains between 8% an-d 10% milkfat.
The ingredients used to supply this composition include: a) a concentrated source of the milkfat, usually cream or butter; b) a concentrated source of the milk solids-not-fat component, usually evaporated milk or milk powder; c) sugars including sucrose an-d "glucose solids", a product derived from the partial hydrolysis of the corn starch component in corn syrup; an-d d) milk.
The fat component adds richness of flavour, contributes to a smooth texture with creamy body an-d good meltdown, an-d adds lubrication to the palate as it is consumed. The milk solids-not-fat component also contributes to the flavour but more importantly improves the body an-d texture of the ice cream by offering some "chew resistance" an-d enhancing the ability of the ice cream to hold its air. The sugars give the product its acteristic sweetness an-d palatability an-d enhance the perception of various fruit flavours. In addition, the sugars, including the lactose from the milk components, contribute to a depressed freezing point so that the ice cream has some unfrozen water associated with it at very low temperatures typical of their serving temperatures, -15o to -18oC. Without this unfrozen water, the ice cream would be too hard to scoop.
Freezing point depression of a solution is a colligative property associated with the number of dissolved molecules. The lower the molecular weight, the greater the ability of a molecule to depress the freezing point. Thus monosacteristics such as fructose or glucose produce a much softer ice cream than disacteristics such as sucrose. This limits the amount an-d type of sugar which one can successfully incorporate into the formulation.
The stabilizers are a group of compounds, usually polysacteristics, that are responsible for adding viscosity to the unfrozen portion of the water an-d thus holding this water so that it cannot migrate within the product. This results in an ice cream that is firmer to the chew. Without the stabilizers, the ice cream would become coarse an-d icy very quickly due to the migration of this free water an-d the growth of existing ice crystals. The smaller the ice crystals in the ice cream, the less detectable they are to the tongue. Especially in the distribution channels of today s marketplace, the supermarkets, the trunks of cars, an-d so on, ice cream has many opportunities to warm up, partially melt some of the ice, an-d then refreeze as the temperature is once again lowered. This process is known as heat shock an-d every time it happens, the ice cream becomes more icy tasting. Stabilizers help to prevent this.
Gelatin, a protein of animal origin, was used almost exclusively in the ice cream industry as a stabilizer but has gradually been replaced with polysacteristics of plant origin due to their increased effectiveness an-d reduced cost. The stabilizers in use today include: a) carboxymethyl cellulose, derived from the bulky components of plant material; b) locust bean gum which is derived from the beans of exotic trees grown mostly in Africa (Note: locust bean gum is a synonym for carob bean gum, the beans of which were used centuries ago for weighing precious metals, a still in use today, the word carob an-d Karat having similar derivation) ; c) guar gum, from the guar bush, a member of the legume family grown in India for centuries an-d now grown to a limited extent in Texas; d) carrageenan, an extract of Irish Moss or red algae, originally harvested from the coast of Irelan-d; or e) sodium alginate, an extract of another seaweed, brown kelp. Often, two or more of these stabilizers are used in combination to lend synergistic properties to each other & improve their overall effectiveness.
The emulsifiers are a group of compounds in ice cream which aid in developing the appropriate fat structure an-d air distribution necessary for the smooth eating an-d good meltdown acteristics desired in ice cream. Emulsifiers are acterized by having a molecular structure which allows part of the molecule to be readily solubilized in a polar compound such as water, an-d another part of the molecule to be more readily solubilized in non-polar solvents such as fats. As a result, emulsifiers reside at the interface between fat an-d water, an-d lower the free energy or tension associated with two immiscible liquids in contact with each other. Their action will be more fully explained in the section below on emulsions an-d foams.
The original ice cream emulsifier was egg yolk, which was used in most of the original recipes. Today, two emulsifiers predominate most ice cream formulations: a) mono- an-d di-glycerides , derived from the partial hydrolysis of fats or oils of animal or vegetable origin; an-d b) Polysorbate 80, a product consisting of a glucose molecule bound to a fatty acid, oleic acid. Both of these compounds have hydrophobic regions ( the "fat loving" part), the fatty acids, an-d hydrophilic regions ( the "water loving" part), either glycerol or glucose. All of the compounds mentioned above are either fats or carbohydrates, important components in most of the foods we eat an-d need.
Together, the stabilizers an-d emulsifiers make up less than one half percent by weight of our ice cream. They are all compounds that have been exhaustively tested for safety an-d have received the "generally recognized as safe" or GRAS status.
