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  1. 1. SUGAR<br />Table sugar or sucrose is extracted from plant sources.<br /> The most important two sugar crops are sugarcane (Saccharum spp.)<br /> and sugar beets (Beta vulgaris),<br />Some minor commercial sugar crops include the date palm (Phoenix dactylifera),<br /> sorghum (Sorghum vulgare), and the sugar maple (Acer saccharum). <br /> <br /> Sorghum Sugarcane Sugar beets Date palm<br />Sugar - Cane<br />The harvested vegetable material is crushed, and the juice is collected and filtered. The liquid is then treated (often with lime) to remove impurities, this is then neutralized with sulfur dioxide. The juice is then boiled, sediment settles to the bottom and can be dredged out, scum rises to the surface and this is skimmed off. The heat is removed and the liquid crystallizes, usually while being stirred, to produce sugar which can be poured into moulds. A centrifuge can also be used during crystallization.<br />Sugar - Beet<br />The washed beet is sliced, and the sugar extracted with hot water in a 'diffuser'. Impurities are precipitated with an alkaline solution "milk of lime" and carbon dioxide from the lime kiln. After filtration the juice is concentrated by evaporation to content of about 70% solids. The sugar is extracted by controlled crystallization. The sugar crystals are removed by a centrifuge and the liquid recycled in the crystallizer stages. Liquid from which no more sugar can be economically removed is lost from the process as molasses and used in cattle food.<br />The white sugar produced is sieved into different grades for selling.<br />Sugar - Types of culinary sugar<br />Raw sugars are yellow to brown sugars made from clarified cane juice boiled down to a crystalline solid with minimal chemical processing. Raw sugars are produced in the processing of sugar beet juice but only as intermediates en route to white sugar. Types of raw sugar available as a specialty item outside the tropics include demerara, muscovado, and turbinado. Mauritius and Malawi are significant exporters of such specialty sugars. Raw sugar is sometimes prepared as loaves rather than as a crystalline powder: in this technique, sugar and molasses are poured together into molds and allowed to dry. The resulting sugar cakes or loaves are called jaggery or gur in India, pingbian tong in China, and panela,panocha, pile, and piloncillo in various parts of Latin America<br /> <br />Demerara Muscovado Turbinado<br /> Sugar cakes or Sugar loaves<br />Mill white sugar also called plantation white, crystal sugar, orsuperior sugar, is raw sugar whose colored impurities have not been removed, but rather bleached white by exposure to sulfur dioxide. This is the most common form of sugar in sugarcane growing areas, but does not store or ship well; after a few weeks, its impurities tend to promote discoloration and clumping.<br />Blanco directo is a white sugar common in India and other south Asian countries. In producing blanco directo, many impurities are precipitated out of the cane juice by using phosphatation a treatment with phosphoric acid and calcium hydroxide similar to the carbonatation technique used in beet sugar refining. In terms of sucrose purity, blanco directo is more pure than mill white, but less pure than white refined sugar.<br />White refined sugar is the most common form of sugar in North America and Europe. Refined sugar can be made by dissolving raw sugar and purifying it with a phosphoric acid method similar to that used for blanco directo, a carbonatation process involving calcium hydroxide and carbon dioxide, or by various filtration strategies. It is then further decolorized by filtration through a bed of activated carbon or bone char depending on where the processing takes place. Beet sugar refineries produce refined white sugar directly without an intermediate raw stage. White refined sugar is typically sold asgranulated sugar, which has been dried to prevent clumping.<br />Granulated sugar is available in various crystal sizes, for home and industrial use depending on the application:<br />Coarse-grained sugars, such as sanding sugar are favored for decorating cookies (biscuits) and other desserts.<br />Normal granulated for table use is typically around 0.5 mm across<br />Finer grades are produced by selectively sieving the granulated sugar<br />caster (0.35 mm) which is commonly used in baking<br />superfine sugar, and are favored for sweetening drinks or preparing meringue.<br /> <br />Finest grades<br />Powdered sugar, confectioner's sugar (0.060 mm), oricing sugar (0.024 mm), are produced by grinding sugar to a fine powder. A small amount of anti-caking agent to prevent clumping may be added, this is either cornstarch (1%-3%) or tri-calcium phosphate.<br />There are also sugar cubes for convenient consumption of a normal amount.<br />Brown sugars are obtained in the late stages of sugar refining, when sugar forms fine crystals with significant molasses content, or by coating white refined sugar with a cane molasses syrup. Their color and taste become stronger with increasing molasses content, as does their moisture retaining properties. They are also prone to hardening if exposed to the atmosphere although this is reversible.<br />Cooking with Sugar<br />Sugar performs a variety of functions in food products, in addition to providing a sweet taste and flavour. Some of its other important properties include its solubility, its ability to absorb water, and its fermentability. These diverse attributes make it an invaluable ingredient to both manufacturers and to those at home.<br />Sweetness of Sugars<br />Sugars vary in their level of sweetness. Sucrose (or table sugar) is the reference standard for which the sweetness of all foods is compared, and is set arbitrarily at 100. Fructose, one of the sugars found in fruit, is the sweetest. Sucrose or table sugar is less sweet than fructose but sweeter than lactose, a sugar found in milk. Below is a chart listing the relative sweetness of common sugars. Keep in mind that sweetness can also vary depending on the form of the sugar (solid, solution), concentration, temperature, presence of other ingredients, and the taste differences between individuals.<br />SugarRelative SweetnessFructose120Sucrose100Galactose70Glucose65Maltose50Lactose25<br />Preserves and Jams<br />Sugar is commonly used as a preservative in jams and jellies, and enhances the colour and flavour of various fruits. Sugars attract water, which acts to inhibit the growth of micro organisms that can cause food to spoil. The addition of sugars to jams and jellies is also essential to the gelling process, to obtain the desired consistency and firmness.<br />Baking<br />Sugar is used in baked goods, like cakes for example, to hold moisture and prevent staleness. It also helps tenderize bakery products and provide a source of nourishment for the growth of yeast, which helps the leavening process (e.g. breads to rise). The browning reaction that sugar undergos when exposed to heat adds flavour, and contributes to the appearance of colour that can be seen on bakery foods such as the crusts of bread and the browning of cookies.<br />Baking Tips:<br />Half the amount of oil in a muffin or quick bread recipe can easily be replaced by a sweet fruit purée, like apple sauce, without affecting its tender texture.<br />Instead of thick rich icing on a cake, drizzle a fruit sauce over it or simply sprinkle with icing sugar.<br />In very fluffy cakes like angel food or sponge cakes, whipping sugar in the cake batter helps to produce the light, fluffy texture.<br />Vanilla sugar is a wonderfully fragrant and flavourful sugar made by burying vanilla beans in granulated or icing sugar -- usually in the proportion of two beans for each pound of sugar. Store the mixture in an airtight container for about a week. The result is a delicious and perfumed sugar to use as an ingredient or decoration for baked goods, fruit and other desserts.<br />Icing sugar -- very finely ground crystals with a touch of starch to prevent lumps -- is excellent for icings and fondants. If the icing sugar becomes packed, simply stir or sift.<br />Canning and Freezing<br />Sugars are added to canned fruits and vegetables to improve flavour, enhance texture and preserve natural colours. Sugars are also used to slow the freezing process, and prevent large ice crystals from forming in frozen sweet mixtures, such as ice cream. Large ice crystals can create a gritty texture, while the formation of smaller ice crystals results in a smoother product, providing a more desirable texture. Sugars also increase the thickness of frozen desserts, imparting a thick, creamy texture in the mouth.<br />Candy<br />Sugar (sucrose) is the primary ingredient in a wide variety of candies, largely due to its solubility. In its simplest form, candy is made by dissolving sugar in water, and heating the solution. As the temperature rises, more sugar can dissolve. The solution is boiled until no more sugar will dissolve (a supersaturated solution). As the solution continues to boil, the water evaporates, making the solution more concentrated. When the solution cools, the sugar’s solubility decreases and the sugar crystallizes out of solution. The type of candy that is being made (and its desired consistency) determines the degree of sugar concentration, and the extent to which sugar particles are recrystallized.<br />Tip:<br />Coarse white sugar is made up of large crystals that are perfect for making hard candies.<br />Beverages<br />Sugars are added to beverages to provide both sweetness and body (otherwise known as “mouthfeel”). Sugars are also important in the brewing and wine-making industry. Sugars or other carbohydrates (except lactose) can be used to produce alcohols by fermentation. During fermentation, yeast feeds on sugars and produces bubbles of carbon dioxide, water and alcohol.<br />General Cooking<br />Sugar is a key ingredient in the preparation of custards, puddings, and sauces. These food products depend on sugar to perform a number of functions, in addition to its role as a sweetener. In custards, sugars help to breakdown proteins in egg (whites) so that they are more evenly dispersed in the liquid mixture. This permits the egg mixture to thicken slowly, mixing with the other ingredients, resulting in a smoother consistency.<br />Sugar helps to prevent lumping and thicken sauces and puddings by separating the starch molecules of the flour (or other thickening ingredient such as cornstarch). This allows for a more desirable consistency.<br />In non sweet foods such as salad dressings, condiments and sauces, sugars enhance flavours and balance the natural acidity of tomato and vinegar based products. This is because sugars are easily broken down by weak acids.<br />Cooking Tip:<br />Enhance sweet potatoes, parsnips or carrots with a no-fat topping -- just add a delicious dash of brown sugar, maple syrup or apple jelly.<br />Storing Sugars<br />Granulated sugars have an excellent shelf life and can be stored in a cool, dry place in their original package for many years. When exposed to moisture, white granulated sugar tends to harden as it dries. Stirring or sifting will usually help to restore its granular state.<br />To soften brown sugar, place a piece of bread or apple in the jar for a few hours and the sugar will regain its original consistency. Hardened brown sugar can also be placed in the microwave for 20 seconds just before using it in a recipe.<br />Once opened, all liquid sugars like maple, corn and table syrups, honey, jams and jellies, must be refrigerated in airtight jars. If syrups begin to crystallize, place container in hot water to heat and then stir vigorously to restore liquid consistency.<br />Functional Properties of Sugar in FoodSensory PropertiesTaste - Sweetness is generally the most recognized functional property of sugar. The preference for sweetness, regarded as being innate, is apparent soon after birth and prior to postnatal learning. Perception of the relative sweetness of sugar depends on factors such as temperature, pH, concentration, presence of other ingredients, and the difference in individuals' ability to taste (e.g. detection threshold).Caramelization - is a browning reaction that results from the action of heat on sugars. At high temperatures, the chemical changes associated with melting sugars result in a deep brown colour and new flavours.Flavour - Flavours result when tastes (sweet, sour, bitter, salty) are combined with sense of smell when food is consumed. Through interaction with other ingredients, sugar is an important contributor to flavour. Depending on the food application, sugar has the unique ability to heighten flavour or depress the perception of other flavours. For example, sugar is added to tomato-based products (e.g. barbeque, spaghetti and chilli sauces) to reduce the acidity of the tomatoes. Sugar itself also provides flavour when it is heated due to caramelization Texture - Sugar makes an important contribution to the way we perceive the texture of food. For example, adding sugar to ice-cream provides body and texture which is perceived as smoothness. This addition helps prevent lactose crystallization and thus reduce sugar crystal formation that otherwise causes a sandy, grainy texture that is sometimes associated with frozen dairy products.In candy-making, controlling the rate and extent of sugar crystallization provides a vast array of textures. These range from the soft textures of fudges where crystallization is minimized, to hard candies where crystallization results in a desired grainy structure.Tenderizer - Sugar acts as an important tenderizing agent in foods such as baked products. During the mixing process, sugar competes with other ingredients for water. In bread making for example, the affinity of sugar to bind to available water will delay the development of gluten, which is essential for maintaining a soft or tender product. Gluten strands, in general, are highly elastic, and this property allows the batter to stretch under the expansion of gases. Too much gluten formation, however, will cause the dough or batter to become rigid and tough. When the correct proportion of sugar is added in the recipe, an appropriate amount of gluten develops and optimum elasticity results.Maillard Reaction - results from chemical interactions between sugars and proteins at high heat. An amino group from a protein combines with a reducing sugar to produce a brown colour in a variety of foods (e.g. brewed coffee, fried foods & breads).Appearance - Sugar is responsible for the yellow-brown colours that develop in baked foods. Sucrose itself develops colour through caramelization. However, the monosaccharide components of its hydrolysis (glucose and fructose) can also undergo browning reactions (Maillard reaction). For example, the reactivity of glucose upon heating contributes to the subtle orange-red colour in bread crust that is a result of this browning.Sugar also contributes to product colour of preserves and jellies through its capacity to attract and hold water. By absorbing water more readily than other components, such as fruit, sugar prevents the fruit from absorbing water which would otherwise cause colour to fade through dilution.Physical PropertiesSolubility - Sugar is very soluble in water. The ability to produce solutions of varying sugar concentrations is important in many food applications. A high level of solubility, for example, is essential in beverages to provide sweetness and to increase viscosity to create a desirable 'mouthfeel'. Its solubility is also important in the preparation of canned fruits, jams, jellies, preserves and syrups to impart the desired level of sweetness and to aid in preservationFreezing Point - Sugar is effective in lowering freezing points. Freezing point depression is an important property in ice-creams, frozen desserts and freeze-dried foods to ensure the development of fine crystal structure and product smoothness.Boiling Point - The concentration of sugar in a solution affects the boiling point by raising it. This characteristic is important in candy manufacture as boiling point elevation allows for more sugar to be dissolved in solution, creating a 'super saturated' and more concentrated solution. It is this specific concentration of the supersaturated sugar syrup, which is achieved at specific boiling points, which inevitably determine the candy's final consistency.Microbial PropertiesPreservation - Sugar plays a role in the preservation of many food products. The addition of sugar to jams and jellies, for example, inhibits microbial growth and subsequent spoilage. Having the ability to absorb water, sugar withdraws moisture from micro-organisms. As a result, micro-organisms become dehydrated, and cannot multiply and cause food spoilage.The interaction between sugar and water controls the level of moisture in baked products. Sugar's high affinity for water helps to slow moisture loss in cakes and biscuits, for example, to prevent drying out and staleness, thereby extending their shelf life.Fermentation - Sugar is extremely important in the baking and brewing industries. Yeasts use sugars as food to produce ethanol, carbon dioxide and water through the process of fermentation. In baking, sugar increases the effectiveness of yeast by providing an immediate and more utilizable source of nourishment for its growth. This hastens the leavening process, by producing more carbon dioxide which allows the dough to rise at a quicker and more consistent rate.Fermentation of sugar by yeast also occurs in the production of wine and beer. Sugar or other carbohydrates are the raw materials for the production of ethanol (alcohol). The extent to which the fermentation reaction is allowed to proceed (degree to which sugar is fermented), contributes to the alcohol content and sweetness of wine, and the flavour of beer.Chemical PropertiesAntioxidant Activity - Sucrose has been reported to exhibit antioxidant properties which help to prevent the deterioration of textures and flavours in canned fruits and vegetables. These effects may be partially attributed to sucrose's ability to lower water activity.In addition, the products of the hydrolysis of sucrose (glucose and fructose) appear to have the ability to block the reactive sites of ions such as copper and iron and, to a lesser extent, cobalt. This characteristic of monosaccharides aids in food preservation by impeding catalytic oxidation reactions.Furthermore, Maillard reaction products are known to have antioxidant properties in food systems. For this reason, some mixtures of Maillard reaction products have been employed in the food industry as food additives for biscuits, cookies and sausages.Summary ChartFunctionsCerealsBeveragesBaked GoodsCakes, CookiesJams, JelliesProcessed FoodsConfectionsDairyFrozen DessertsSweetenerXXXXXXXXXTexturizerXXXXXPreservativeXXX    AntioxidantX    Shelf Life ExtenderXXXFermentationXXAppearance    Caramel-izationXXX    Maillard ReactionXXXSolubilityXXXXFreezing PointXBoiling PointX<br />