Lab 4: Beverages and Sugar: Frozen Desserts and Cenfectioners. Baking 1a Flashcards
Describe frozen desserts
Ice crystals surrounded by a sugar syrup
Name some examples of frozen desserts
ice cream, ice milk, imitation (mellorine, frozen tofu), waster ices, sherbets and still frozen (mousse, parfaits).
Ice milk contains milk instead of cream
Mellorine has vegetable fat instead of milk fat
Frozen tofu contains soy bean protein, HFCS and corn oil
Sherbets contain milk, cream or egg whites
Still-frozen (no stirring) contain large amounts of whipped cream, gelatin or egg whites
What are the factors affecting the quality of frozen desserts? (6)
- Sugar: At extreme temperatures, it is hard for the taste buds to register a sweet taste.
- Milk Solids: Nonfat milk solids are added to ice cream for body and a smooth texture. Too much nonfat milk solids makes for a sandy texture b/c lactose is insoluble and these large grains can be felt by the tongue. ex. evaporated milk
- Fat: for a rich body and a smooth texture. Too much will make it too hard.
- Emulsifiers: smooth texture due to the incorporation of minute air bubbles and stabilize foam structure during storages. ex. Mono-, di-glycerides and egg yolks (lecithin)
- Stabilizers: restrict crystal growth during storage. ex. Guar gum, carrageenan
- Temperature of the freezing mixture: the ratio of salt: ice: water and the size of salt crystals and pieces of ice affect the temperature attained by the brine.
How are frozen desserts made?
Made by agitating the ingredient mixture at a cold temperature. Water in the frozen dessert mixture converts to ice crystals. Agitation allows small ice crystals to form and to incorporate air. Ice water and salt brine is used to withdraw heat from the ingredient mixture so that it becomes cold enough.
How is sugar produced?
from the juice extracted from sugar canes and sugar beets. Boiled down to a thick syrup, tiny seed crystals are added to grow into larger crystals (crystallization)
What of large sugar crystals make?
molasses, brown sugar and granulated white sugar
What is blackstrap molasses?
residual obtained in the refining processing, contains more nutrients (iron) than white or brown sugar
How ate icing sugar or powder sugar made?
Pulverize granulated sugar. Corn or wheat starch prevents caking
How is honey made?
from bees, they collect nectar from flowers. Accumulate nectar in their esophagus, mixes with saliva to make honey.
How is maple syrup made?
Concentrating (40x) the clear sap from maple trees. Becomes golden brown due to caramelization of fructose.
What nutrient does maple syrup contain? Who is the largest producer?
Potassium.
Quebec, Canada
What are the functional roles of sugar in Food preparation? (6)
- Food preservation: inhibits microbial growth, keeps F+V firm
- Osmotic dehydration: foods dehydrated at RT, using a sugar solution
- Crisp Texture: recrystallizes as water evaporates in baked goods. Maillard reaction (chemical rxn between glucose or fructose w/ nitrogen (protein) containing ingredients. Caramelization of fructose. Tenderizes baked goods, improves shelf life.
- Fermentation: breads and beer
- Candies: determines their smoothness
- Lowers the freezing point of a solution, in frozen desserts, ensures smaller ice crystals, smoother product
Describe Candy
A network of sugar crystals suspended in a supersaturated solution. Molecules in a sugar syrup are attracted to each other, when they join, they form crystals.
What are the 2 categories of candies?
Crystalline : very small sugar crystals not perceived by the tongue. ex. fudges, fondant, panocha, divinity
Noncrystalline: can be chewy (caramels), hard (peanut brittle) or aerated (marshmallows, gum drops).
What do we want to avoid when making candies?
Prevent crystal formation all together. Interfering agents are added at the beginning
What are the factors affecting the size or rate of crystal growth? (4)
- Crystal interfering Agents: added to interfere with the rate of crystallization. Slows the speed at which nuclei grow into crystals.
- Concentration of the sugar solution: Crystallization will only occur if a sugar solution is supersaturated with sucrose. The more supersaturated it is, the faster it will crystallize.
- Temperature: of a sugar syrup is an index of its concentration
- Agitation: incorporates air, promotes formation of crystal nuclei by redistributing impurities which delay crystal formation, breaks up large crystals and hastens crystallization
What are some examples of Crystal Interfering Agents?
Butter, cream, egg whites, cocoa powder, gelatin, invert sugar, sucrose, glucose and corn syrup.
These provide fat, protein, air, dextrins and simple sugars that coat the crystals, impeding growth.
How can crystallization be initiated?
By a speck of dust or a grain of sugar.
Wash the sides of the pot with hot water to dissolve the sugar, or place a cover on the pot to create steam
T or F: the sugar solution should be stirred once it is boiling
F: Don’t stir!
What is invert sugar?
An equimolar mixture of glucose and fructose that is formed with sucrose (table sugar) is heated in the presence of an acid (cream of tartar, molasses, vinegar) or enzyme invertase.
When invertase is cooked too long? too little?
Too long: becomes soft
Too little: becomes hard, brittle
What is a supersaturated solution?
A solution that contains a higher concentration of sugar than it would at room temperature. Can be achieved by heating the sugar solution above the boiling point of water to let the large sugar crystals dissolve, then letting it slowly cool w/o agitation.
T or F: as temperature cools, crystallization speeds up, molecules come close together.
True
How is the boiling point of a sugar solution determined?
BP increased every 0.52 C/ 1 mol of sugar
1 mol sugar = 342g sucrose
How the doneness of candy determined ? (3)
- Temperature of the syrup: use a thermometer (test it in boiling water first)
- Cold water Test: measures the consistency of the syrup when dropped in cold water.
- thread stage: doesn’t harden
- soft ball: soft but firm, like fudge
- firm ball: for caramel
- hard ball: divinity, taffy, nougat
- soft crack: brittle threads form, very hard candy
What is the most influential factor on crystal size when making candy?
The temperature of the candy solution before agitation begins
If agitation occurs when the solution is cooled appropriately,
tiny crystals form all at once, resulting in a creamy texture
If agitation occurs when the solution is hot,
large crystals form because of the rapid movement of molecules. They are farther apart, less nuclei formed, each one grows larger as the temperature cools.
During the cooling process if there is contact with rough surfaces or seeding from dust or extra sugar crystals,
rapid crystallization can occur, leads to large crystals
What is caramelization?
A nonenzymative browning involving a number of reactions that occur when sugar is heat. Organic acids formed as sugar decomposes.
Baking soda is added to caramelized sugar to react with the organic acids to produce bubbles of CO2.
What are the 2 ways to make caramel?
Dry Method: uses only sugar,
Wet Method: uses some water. Do not stir until all water has been evaporated.
Interfering agents can be added to prevent crystallization.
What does good coffee look like?
Amber brown, clear of sediment, ,mild, brisk flavour
What is the goal of brewing? How is this achieved?
extract the maximum of caffeine and flavouring substances but minimizing the amount of polyphenols (tannins)
Achieved if water contact with the coffee grounds is limited and the temperature does not rise to boiling
What kind of coffee defies all the rules for ‘good coffee’?
Turkish coffee
Instant coffee vs brewed coffee?
Instant coffee lacks the rich flavour.
Freeze drying coffee ______ the flavour and _____ the cost
improves the flavour and increases the cost
Green tea is ________ and _____ in colour
Highly astringent, light in colour
Why are black teas full bodied and darker in colour?
Because the leaves are fermented
Which tea contains both characteristics as green and black tea? is it fermented?
Oolong tea. (partially fermented)
Adding lemon juice to overextracted tea
Lighter in colour, changes the pH
T or F: residual oils in the coffee pot don’t make the coffee bitter
F
Coffee: Too fine/large a grind will result in too ____
strong, weak
For medium strength coffee, how much coffee and water should be added?
15 ml coffee, 175 ml water
The coffee pot should be filled to ___ of its capacity for the best quality brew
3/4
Why should coffee grounds be discarded immediately after use?
They absorb the aroma from the brew
T or F: storing fresh coffee in a thermal carafe preserves the fresh taste whereas keeping it in the coffee maker will result in flavour deterioration
True
When should athletes start replenishing muscle glycogen stores? What kind of snack is ideal?
15-30 mins
Rich in CHO, moderate in protein and low in fat
What is removed in juicing?
fibre
high fibre ingredients make baked goods dense or light?
Dense
What are some common fibre rich ingredients used in muffins? (2)
Wheat bran and oat bran
What are some high fibre ingredients added to baked goods?
Fruit purees, dried fruit, legume flour, psyllium seed husks
