标题：History of Ice Cream关键字：History of Ice Cream, ice cream knowledges, ice cream develop描述：History of Ice Cream, ice cream knowledges, ice cream develop图片：描述：History of Ice Cream内容：The first frozen dessert is credited to Emperor Nero of Rome. It was a mixture of snow (which he sent his slavesinto the mountains to retrieve) an-d nectar, fruit pulp an-d honey. Another theory is Marco Polo, 13th century bardan-d adventurer, brought with him to Europe from the Far East recipes for water ices.said to be used in Asia forthousan-ds of years.In 1700 Governor Bladen of Maryl an-d served ice cream to his guests.The first ice creamparlor in America opened in New York City in 1776.Dolly Madison created a sensation when she served ice creamas a dessert in the White House at the second inaugural ball in 1812.Italo Marchiony sold his homemade ice creamfrom a pushcart on Wall Street. He reduced his overhead caused by customers breaking or w b) between 9 an-d 12% milk solids-not-fat, the component which contains the proteins (caseins an-d wheyproteins) an-d carbohydrates (lactose) found in milk; c) 12% to 16% sweeteners, usually a combination of sucrosean-d glucose-based corn syrup sweeteners; an-d d) 0.2% to 0.5% added stabilizers an-d emulsifiers, necessarycomponents that unfortunately have unfamiliar sounding names that occupy three-quarters of the space of theingredient listing an-d that will be described subsequently. The balance, usually 55% to 64%, is water, whichcomes 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 thiscomposition include: a) a concentrated source of the milkfat, usually cream or butter; b) a concentrated source ofthe 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 goodmeltdown, an-d adds lubrication to the palate as it is consumed. The milk solids-not-fat component also contributesto the flavour but more importantly improves the body an-d texture of the ice cream by offering some “chewresistance“ an-d enhancing the ability of the ice cream to hold its air. The sugars give the product its acteristicsweetness an-d palatability an-d enhance the perception of various fruit flavours. In addition, the sugars, includingthe lactose from the milk components, contribute to a depressed freezing point so that the ice cream has someunfrozen 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 acolligative property associated with the number of dissolved molecules. The lower the molecular weight, thegreater the ability of a molecule to depress the freezing point. Thus monosacteristics such as fructose or glucoseproduce a much softer ice cream than disacteristics such as sucrose. This limits the amount an-d type of sugarwhich one can successfully incorporate into the formulation. The stabilizers are a group of compounds, usuallypolysacteristics, that are responsible for adding viscosity to the unfrozen portion of the water an-d thus holding thiswater so that it cannot migrate within the product. This results in an ice cream that is firmer to the chew. Withoutthe 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 thetongue. Especially in the distribution channels of today s marketplace, the supermarkets, the trunks of cars, an-d soon, ice cream has many opportunities to warm up, partially melt some of the ice, an-d then refreeze as thetemperature is once again lowered. This process is known as heat shock an-d every time it happens, the ice creambecomes more icy tasting. Stabilizers help to prevent this. Gelatin, a protein of animal origin, was used almostexclusively in the ice cream industry as a stabilizer but has gradually been replaced with polysacteristics of plantorigin due to their increased effectiveness an-d reduced cost. The stabilizers in use today include: a) carboxymethylcellulose, derived from the bulky components of plant material; b) locust bean gum which is derived from thebeans of exotic trees grown mostly in Africa (Note: locust bean gum is a synonym for carob bean gum, the beansof which were used centuries ago for weighing precious metals, a still in use today, the word carob an-d Karathaving similar derivation) ; c) guar gum, from the guar bush, a member of the legume family grown in India forcenturies an-d now grown to a lim