Lab 4 Flashcards
Frozen desserts consist of ____ surrounded by what?
Ice crystals surrounded by a sugar syrup.
Ice milk contains ___ instead of what?
Contains milk instead of cream.
What is mellorine?
Dessert with vegetable fat instead of milk fat
What are the 6 factors which affect the quality of frozen desserts?
1) Sugar 2) Milk solids 3) Fat 4) Emulsifiers 5) Stabilizers 6) Temperature of Freezing Mixture
How does sugar affect the quality of frozen desserts?
Hugh concentrations of sugary be used since the sweetness of a frozen dessert is attenuated by cold temperature.
How does milk solids affect the quality of frozen desserts?
Improve body and promote smooth texture.
What happens if too much non-fat milk solids are added to ice-cream?
Create a sandy extra because lactose is relatively INSOLUBLE, will precipitate into large crystals that the tongue can detect.
Milk solids can be added in the form of …
evaporated milk
How does fat affect the quality of frozen desserts?
Creates a rich body and smooth texture
Why is the amount of fat limited in frozen desserts?
Too much can create a too hard product
How does emulsifiers affect the quality of frozen desserts?
Promote smooth texture by incorporation of minute air bubbles, and stabilize foam structure during storage.
What are some common emulsifiers?
Mono and di glycerides. Egg yolk because of its lecithin content
How do stabilizers affect the quality of frozen desserts?
Restrict crystal growth during storage. i.e carrageenan and guar gum
How does temperature of the freezing mixture affect the quality of frozen desserts?
The ratio of ice to salt water and the size of salt crystals and pieces of ice affect the temperature attained by the brine
Most frozen desserts are made by _____
Agitating the mixture at a low temperature, created ice crystals from water in the mixture.
Why is motion needed to make frozen desserts?
Keeps the crystals small and will incorporate air
Pure ice cannot __
freeze water
How does an ice cream maker work?
brine = iceboater and salt, or coils or refrigerant in industry will withdraw heat from the mixture so it becomes cold enough for ice crystals to form.
Sugar is produced from what?
The juice extracted from sugar canes and sugar beets
How is the juice boiled down?
Boiled down to a thick syrup to which tiny seed crystals are added and are allowed to grow into a larger sugar crystals by crtallization.
What are large crystals refined into after crystallization?
Molasses, brown sugar and granulated white sugar.
How are blackstrap molasses created?
The residual obtained in the refining process.
what nutrient is higher in blackstrap molasses?
Iron
How is powdered sugar or icing sugar made?
Pulverized granulated white sugar, sometimes corn or wheat starch is added to prevent caking.
How is honey produced ?
When bees collect nectar from flowers, which will accumulate in their esophagus. Mixed with their saliva, will turn into hint and will be deposited to the beehive.
How is maple syrup produced?
Concentrating 40x the clears from maple trees in the sign, includes caramelization of fructose which results in the golden brown product.
What nutrient is significant in maple syrup?
Potassium
Maple syrup s only produced where? What province is the largest producer?
Only produced in North America, Quebec is largest producer.
In food preservation, sugar inhibits ____ and keeps fruits and vegetables ___
inhibits microbial growth and keeps fruits and vegetables firm
What process is sugar used as in the industry? What happens?
-osmotic dehydration Fruits, vegetables and fish are dehydrated at room temperature using a sugar solution Results in removal of water form food.
how do baked goods achieve their crisp texture ?
Sugar recrystallizes as water evaporates resulting in a crisp texture
What is the Maillard reactions?
Non-enzymatic Non-oxidative growing resulting from a chemical reaction between reducing sugars glucose, fructose and nitrogen (protein) containing ingredients.
How does caramelization occur?
Heat, also contributes to browning and new flavours (fructose)
How does sugar tenderize baked goods?
Slows the rate of gelatinization and gluten development
Sugar slows down what ?
Slows down moisture loss and extends shelf life
How does sugar influence bread making and brewing industries ?
Influences the rate of fermentation
Sugar determines the _____ of candies
Smoothness
In frozen desserts, does sugar increase or decrease the freezing point of a solution? what happens?
DECREASES freezing point of solution - this ensures smaller crystals and a smoother product
Candy is ___
a network of sugar crystals suspended in supersaturated solution.
How are the crystals formed in candy?
Molecules in sugar syrup are attracted to each other
How are the size, arrangement and shape ?
Influenced by interfering agents and agitation - which result in different textures
what two categories can candies be divided into?
Crystalline and Non Crystalline
What are crystalline candies? What are some examples?
Contain very small sugar molecules not perceivable by the tongue. Fudge and fondant
What are non crystalline candies? What are some examples?
Can be chewy (caramel), hard (brittle) or aerated (marshmallows and gum drops)
What is the goal in making candies ?
To prevent crystal formation all together, interfering agents are added at the beginning of preparation.
What are some factor that affect the size or rate of crystal growth?
Crystal interfering agents Invert Sigar Concentration of Sugar solution Temperature
What are crystal interfering agents?
Are deliberately added to interfere with the rate of crytallization
What is crystallization? How do interfering agents affect crystallization?
The speed at which nuclei grow into crystals, and result in smaller crystals which will produce a smoother texture.
What are some examples of crystal interfering agent?
Butter Cream Milk Egg white gelatin Cocoa Invert Sugar Sucrose Glucose Corn Syrp
What are the characteristics of a crystal interfering agent?
Provide fat, protein, air and dextrin and simple sugars that surround or coat the crystals and impede growth
What can initiate crystallization?
A speck of dust or grain of sugar
What happens if sugar accumulates on the side of the pan?
Should be dissolved using a brush dipped in hot water or by placing the over on the pot to create steam.
What is invert sugar?
An equimolar mixture of glucose and fructose that is formed when sucrose (table sugar) is heated in the presence of an acid or the enzyme invertase.
What does invert sugar act as?
An interfering agent
What are some acids used in candies to produce invert sugars?
ream of tartar, vinegar, molasses.
The formation of invert sugar us dependent on what? What happens if cooked too long or too little?
Dependent on cooking time, if cooked too long will produce a soft candy and too little will create a coarse and granny product.
Crystallization only occurs if a sugar solution is _____
Super saturated with sucrose
The more supersaturated the sugar solution is, the _____
faster the solution will crystallize.
What is a super saturated solution?
The concentration of sugar dissolved is greater than it normally would be at room temp.
What are the two ways to accomplish a supersaturated solution?
1) Heat sugar solution above boiling pt of water so large amount of sugar dissolve 2) slowly let it cool without agitation, as temp decrease, crystallization increases and molecules are closer together as temperature cools
Why is heating a sugar solution to the proper temperature critical?
Because the temperature of a sugar syrup is an index of its concentration
How can the concentration of sugar in a sugar syrup be determined?
By measuring boiling point because the boiling point
How is the boiling point raised?
raised 0.52 C for every mol of sugar dissolved in 1 L of water
What is 1 mol of sugar ?
342 g of sucrose
What can alter the boiling point of sugar ?
Barometric pressure, interfering agents and altitude
How can the doneness of candy be measured by?
-temperature of syrup using a thermometer -cold water test
What is the cold water test?
Measures the consistency of syrup when dropped in cold water, a drop of syrup is made to fall off the edge of a spoon into a glass of cold water
The stages of sugar syrup are:
Thread stage soft ball firm ball hard ball soft crack
What is the thread stage?
The syrup will not harden
What is the soft ball?
For soft but firm candy like fudge
Firm ball?
for caramels
Hard ball?
Divinity, taffy, nougat
Soft crack?
brittle threads form; will form very hard candy
What is each stage associated with?
The temperature which is found on candy thermometers
Why is it critical to cool they syrup to the proper temperature before agitation beings?
Because the temperature of the candy solution at the time of beating is the most influential factor on crystal size
Wha is the most influential factor on crystal size?
Temperature of the candy solution at the time of beating
What is the thread test? At what temperature will it be removed from heat? what are some examples?
A spoonful of sugar drizzled over a plate forms a thin three, makes a syrup and not a candy. 106-112C Bind Agent for fruit pastes
What is the softball test? At what temperature will it be removed from heat? what are some examples?
Small amount of sugar syrup is dropped into very cold water and forms a ball that does not hold shape when pressed with fingers 112-116C -Fudge, Fondant, Creams, Penuche, Maple
What is the firmball test? At what temperature will it be removed from heat? what are some examples?
Same as softball, but its ball will hold its shape and remains sticky when pressed with fingers 118-120C Caramels and Divinity
What is the Hardball? At what temperature will it be removed from heat? what are some examples?
Same as softball, but ball can be stretched between finger s and pliable. 121-130C Taffy and Marshmallows
What is the soft crack test? At what temperature will it be removed from heat? what are some examples?
Same as softball, but ball can be stretched between fingers into separated ut not brittle threads. 132-143C Butterscotch and taffy
What is the hard crack test? At what temperature will it be removed from heat? what are some examples?
Small amount of sugar dropped into very cold water and will solidify but still operated into hard and brittle threads. 149-154C Peanut Brittle
What is the the Light caramel test? At what temperature will it be removed from heat? what are some examples?
Poured onto a white plate,the syrup will be a honey-golden in colour. 160-170C Glazes, coating agent
What is the dark caramel test? At what temperature will it be removed from heat? what are some examples?
Poured onto white plate, the syrup will be a deep-reddish amber in colour. 177C Glazes, coating agent
What is agitation?
Incorporated air and promotes the formation of many crystal nuclei by redistributing impurities, which delay crystal formatting and break up large crystals and faster the crystallization.
When should agitation begin?
Only after candies have been cooled to a certain temperature and must continue until crystallization is complete.
What happens if syrup is beaten while still hot?
Large crystal form because of the rapid movement of molecules, they are father apart so less nuclei are formed, and each one grows larger as temperature cools.
What happens when the sugar solution is cooled properly?
Tiny crystals result in a smooth texture
What is caramelization? What is it facilitated by?
Non enzymatic growing involving a number of reactions that occur when sugar is heated. Facilitated by presence pf acid.
How are organic acid formed?
Formed as the sugar decomposes.
What can be added when making peanut brittle?
Being soda may be added, the soda and organic acid will react which creates the holes in the brittle
What are the two meths to prepare caramel?
Dry and Wet method
What is the dry method?
Uses only sugar,
What is the wet method?
sugar and a bit go water, and should not be stirred until all the water has evaporated and looks lie layers of bubbles or else the star will crystallizes.
In general, what is good quality coffee considered to be?
Amber brown, clear of sediment, with a mild and brisk flavour.
What is the goal when brewing coffee?
To extract the maximum amount of caffeine and flavouring substances while minimizing the concentration of polyphenols (tannins)
How can maximum flavour and caffeine be extracted ?
When water contact with ground is limited and the temperature does not rise to boiling
Which type of coffee disregards all these principles?
Turkish coffee
How can the flavour of instant coffee be improved?
Freeze drying, but may also increase cost.
What does processing of green tea affect?
Flavour
Green tea is _____
highly astringent and light in colour
How is a full bodies flavour and darker coloured develop?
When leaves are fermented, such as black tea.
What is oolong tea?
Fermented tea with characteristics of both green and black tea
What results from over-extracting tea leaves and over steeping?
Bitter, unpalatable beverage
What results of adding lemon juice to tea?
Change in pH and lighter colour
Where re some principles of coffee brewing?
-Clean Coffee pot: residual oils can taint freshly brewed coffee -Proper grind, if too fine coffee may be too strong, too large coffee may be too weak -fill coffee pot to 3/4 its capacity -remove and discard coffee grounds since they can absorbs aroma from the brew -store fresh coffee in a thermal carafe preserves fresh taste
What is the guideline for preparing medium strength coffee?
15 mL ground coffee/175 mL water
What are the general principles of tea preparing?
-Fill cup with hot water -Boil water -Add tea to each cup, add loose tea to steeper -Pour boiling water (250-500ml / bag or 15 ml loose tea) -let steep for 3-5 mins -Remove ans serve
Describe the processed of sugar beets -> sugar formation
See photo
