Chapter 8 - Sugar: The simplest carbohydrate
In food preparation, sugar functions as a
- sweetener - preservative - tenderizer - crystallizing agent - caramelizing agent - fermenting agent
Supersaturated solution
Created when sugar solution is heated to concentrate the sugar then cooled - candy is made when sugar crystals separate from a supersaturated sugar solution during cooling - the finer the sugar crystals are, the higher the candy's quality will be
_____ and _______ are changed to glucose in the liver
Fructose and galactose
Glycogen
Glucose is stored as it in the muscle and liver - it lets the body quickly access large amounts of glucose for energy when needed
Maple syrup
Source of sugar > concentrated sap for sugar maple trees is slowly simmered to make the costly syrup > economical subsititues are made with corn syrup
corn syrup
Source of sugar > is processed by hydrolyzing cornstarch into glucose. > is composed of dextrose, malotse, and dextrins or polysaccharides
High fructose corn syrup
Technology allows enzymes to convert starch from corn into sweet syrups - HFCS
sugars
simplest form of carbohydrates
Sources if sugar include
- sugar cane and sugar beets - maple and corn syrup - sorghum - honey - isomalt
Functions of sugars in food preparation
1. Sugars sweeten food 2. Sugars act as preservatives 3. Sugars function as tenderizers 4. Sugars act as crystallizing agents 5. Sugars act as caramelizing agents 6. Sugars function as fermenting agents
sugars provide _____ calories per gram
4
Dental carries
> Result form bacteria in the mouth feeding on sugar and producing plaque > can be prevented with regular brushing and flossing along with seeing a dentist
Sorbitol
> Sources include fruits (apples, berries, pears, plums); seaweed, algae > 2.6 kcal/g
Xylitol
> Sources: Apple, berries, plums, and other foods > 2.4 kcal/g
Sugars sweeten food
> ability to sweeten is because sugars have up to ten units of monosaccharides > the sweeter the sugar is, the simpler the structure of the molecule > researchers identified a site on sugar that bonds to taste buds and registers a sweet flavor by the nervous system
Carbohydrates
> are compounds composed of carbon, oxygen, and hydrogen > make up the bulk of the biomass of food > are a major source of energy > are a vital part of cell structure and the base of DNA molecules > include sugars, starches, and fiber
alcohols
> are organic compounds that contain at lease one -OH group > ethanol is the alcohol in alcoholic beverages > methanol is produced by burning wood without oxygen present > isopropanol is rubbing alcohol
Nutritional value of sugar
> body needs sugars for the digestion of fats and proteins > steady of supply of glucose is needed for brain function > sugars increase the release of the brain chemical serotonin, which has a calming effect > dietary guidelines recommended limiting added sugars to approx 6.5% of total calories consumed
Weight gain
> caused by consuming excess sugar > can be controlled by balancing calorie intake with calories burned by the body
Health care concerns related to sugar intake
> dental caries > diabetes mellitus > weight gain
Sucrase
> enzyme involved in the digestion of sugar (sucrose) > present in saliva
Glycerol
> exists in wine and beer > by-product of soap manufacture > 2 kcal/g
Mannitol
> extracted from seaweed > 1.6 kcal/g
invert sugar
> fructose and glucose mixture that results from hydrolysis of sucrose results in the hydrolysis of sucrose by sucrase, also called invertase
Diabetes mellitus
> is the body's inability to move glucose from the bloodstream to the cells because of insulin levels > may be controlled by eating nutritious foods in 5 to 6 small meals daily and regular follow up with the doctor
Candy making tips include
> monitoring temperature with a candy thermometer > following preparation directions exactly
three conditions that trigger hydrolysis
> presence of enzyme to set off reaction > addition of acid > addition of heat
Sugars as crystallizing agents
> sugar dissolved in water because of the large number of hydroxyl groups > as sugar is heated, water will evaporate increasing the sugar concentration
saccharide
> the chemical name for sugar > defined as having one or more hydroxyl groups.
Molasses
> the crude, boiled liquid pressed from sugar cane > give brown sugar its moist and distinctive flavor + color
Sugars function as tenderizers
> the more sugar a baked product contains, the more tender crumb it will have > sugar changes the viscosity or pourability of doughs and batters because sugar interferes with flour's ability to form an elastic structure
Sugars can fit into a healthful diet when....
Eaten in moderation
Solubility
Is the ability of a solute to dissolve in a solvent
Isomalt
Source of sugar > mixture of mannitol, sorbitol, and beet sugar > colors easily and does not form crystals > used on blown, spun, and shaped sculptures
Sorghum
Source of sugar > sap is extracted from sorghum canes and boiled to evaporate excess water, eventually resembling molasses
sugar beets
Source of sugar > sucrose from sugars beets, preforms the same as sucrose from cane sugar but is usually more economical
Sugar cane
Source of sugar > the chinese developed the extraction process > curde boiled liquid pressed from cane is molasses > brown sugar is unrefined or partially refined cane sugar > granulated sugar is refined brown sugar > confectioner's sugar is granulated sugar, that is ground into a fine powder
sweeteners are
Source of sugar > used by food companies in products to optimize sweetness and minimize costs > extracted from plants with high sugar content Eg. Sugar cane, sugar beets, maple trees, corn, sorghum, and honey
Honey
Source of sugar > bees extract an invert sugar from the pollen of flowers and store it in hives > flavor relates to the type of flower
Sugars function as fermenting agents
Sugar is fuel for the microorganism growth needed to make fermented products such as yeast breads, beers, and wine
Caramelization
Sugars act as caramelizing agents - occurs when sugar is heated for a prolonged period and darkens to a brown liquid
galactose
monosaccharide, basic sugar found in milk
fructose
monosaccharide, found in fruits and honey
glucose
monosaccharide, the most abundant of the sugars and the basic energy source for humans
labeling of sugars
must be listed seperately on a food ingredients label
Excess glucose is stored as _______ in the muscle and liver
Glycogen
Photosynthesis
Process by which plants convert energy from the sun into glucose
Hydrolysis
When sugar is divided into smaller parts by adding water
Factors affecting crystal formation include
> the type of sugar - sucrose increases crystal size, but invert sugar slows formatiom. > interfering agents - corn syrup, butter, egg white, cream of tar tar, cream, and vinegar prevent or slow crystal growth > agitation - stirring forms large crystals in hot syrup, but prevents them in cooled syrup > cooling - a cooler syrup will crystallize rapidly into a smoother texture > ripening - allowing the candy to rest promotes a smooth creamy texture
Sugars act as preservatives
> they help prevent food spoilage by drawing water away from bacteria > they only preservative needed for candies, jams, jellies, and syrups is sugar > sugars maintain moisture in cakes > invert sugar is most effective in maintaining freshness of baked goods
monosaccharides
contain carbon, hydrogen, and oxygen atoms in a central ring structure > fructose > glucose > galactose
maltose
disaccharide, found in malted grains glucose + glucose
lactose
disaccharide, sugar in milk glucose + galactose
sucrose
disaccharide, table sugar glucose + fructose
each type of sugar requires a different _______ for hydrolysis
enzyme
Sweet alcohols
glcyerol, mannitol, sorbitol, xylitol are used as additives that are sweet
hydroxyl groups
groups in which a hydrogen atom is bonded to an oxygen atom (-OH)
disaccharde
joins 2 monosaccharides > sucrose > maltose > lactose
hydrolysis
the body uses this reaction to digest disaccharides > a large molecule is divided into smaller parts by adding water