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Flashcards in workshop 3 Deck (15)
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1
Q

factors affecting quality of frozen desserts (5)

A
  1. SUGAR: high concentration may be used because the sweeteness of frozen dessert is attenuated by cold temperature
  2. MILK SOLIDS: they are added to ice cream to give it more body and to promote a smooth texture.
    - too many= sandy texture because lactose is relatively insoluble + easily precipitates into large crystals that can be felt by the tongue
    * can be added on form of evaporated milk
  3. FAT: creates a rich body and a smooth texture in frozen dessert
    - too much= hard product
  4. EMULSIFIERS: promotes smooth texture by incorporation of minute air bubbles and stabilize foam structure during storage
    - common emulsifiers= mono + di-glycerides, egg yolk for its lecithin content
  5. STABILIZERS: restrict crystal growth during storage
    * guar gum and carrageenan
  6. TEMPERATURE OF THE FREEZING TEMPERATURE:
    - made by agitating the mixture at very low temp
    - water forms ice crystals
    - motion= kep ice crystal small + incorporate air
    - coils or refrigerant in industry= use to withdraw heat from the mixture so it becomes cold enough for ice crystals to form
    - temper. attain by the brine is affected by the ratio of ice to salt to water + size of salt crystals
2
Q

what is frozen desserts + different types

A
  • it consists of ice crystals surrunded by sugar syrup
    1. ice cream
    2. ice milk (contains milk instead of cream)
    3. imitation (mellorine= has vegetables fat substitued for milk fat and frozen tofu= tofu or soybean protein, high-fructose corn sweetener + corn oil)
    4. water ices (granita)
    5. sherbets and stiff-frozen (mousses, parfait)

** all large amount of whipped cream, gelatin or egg whites

3
Q

sugar production

A
  • produiced from the juice extracted from sugar cans and sugar beets
    1. juice is boiled down to a thick syrup to which tiny crystals are added and allowed to grow into larger sugar crystalls (cystallisation)
    2. large crystals are refine into molasses, brown sugar + granulated white sugar
  • blackstrap molasses= residual obtained in the refining process (more nutrients like iron than white or brown sugar)
  • icing sugar + powdered sugar = pulverized granulated whit sugar + corn or wheat starch to prevent caking
  • honey: produce by bees who collect nectar from flowers (accumulate in their esophagus + mixes with saliva to form honey)
  • maple syrup: by concentrating (40 times) the clear sap tapped from certain maple trees, contains K, include caramelization of fructose
4
Q

10 roles of sugar

A
  1. food preservation: inhibits microbial growth + keeps F and V firm
  2. industry: for osomotic dehydration so F,V and fish are dehydrated at room temp with sugar solution,removing water from food
  3. baked goods: re-crystallizes as water evaporates= crisp texture
  4. maillard reaction reaction: non-enzymatic non-oxidative browning resulting from a chemical reaction between reducing sugars glucose + fructose and nitrogen (protein) containing ingredients
  5. caramelization of fructose due to heat= contributes to browning + new flavors
  6. tenderizes baked goods: slow rate of gelatinization + gluten development
  7. slows moisture loss, extending shelf life
  8. breand making + brewing industries: influences rate of fermentation
  9. determines smoothness of candies
  10. frozen desserts: lowers freezing point of solution, ensuring smaller crystals + smoother product
5
Q

what are candies

A

def: it is a network of sugar crystals suspended in a supersaturated solution
* molecules in sugar syrup are attracted together + form crystals
- divide in crystalline and noncrystalline:
1. crystalline= fudge, fondant, panocha (contain very small sugar crystals not perceivable by tongue)
2. noncrystalline: chewy (caramel), hard (brittles), aerated (marshmallow): goal is to prevent formation of crystal

6
Q

4 factors affecting size of crystals in candies

A
  1. CRYSTAL INTERFERING AGENTS: smoother textur with smaller crystals
    - interfere with rate of crystallization, speed at which nuclei grow into crystals
    - ex: eggs white, butter, cream, milk, gelatin, cocoa, inverted sugar
    * all provide fat, protein, air, dextrins and simple sugar that surrunded or coat crystals and impeded the growth
    * accumulation of sugar in the pan should be dissolved : put the cover to create steam or use a brush dipped in hot water
    * syrup= not stir during boiling
  2. CONCENTRATION OF SUGAR SOLUTION:
    - crystallization occurs if a sugar solution is supersaturatd with sucrose (the more it is, the faster it crystallizes)
    - supersaturated= concentration of sugar dissolved is greater than normally would be at room temp.
    2 ways to accomplished supersaturation:
    1) heating a sugar solution above boiling point of water= large amount of sugar dissolve
    2) slowly letting it cool without agitation
    - when it cools: crystallization speeds up (molecules become closer)
  3. TEMPERATURE:
    - heating sugar solution to the good temp= critical because temp of the sugar syrup= index of its concentration
    - super-saturation= rapid + small crystals
    - concentration of sugar in sugar syrup = measure by measuring boiling point (it raises of 0.52C by every mole of sugar (342g fro sucrose)) dissolved in 1L of water.
  4. AGITATION:
    4 roles:
    a) incorporates air
    b) promotes formation of many crystal nuclei by redistributing impurities (delay cristal formation)
    c) breaks up larger crystals
    d) hastens crystallization
    - begin AFTER CANDIES HAVE COOLED TO A CERTAIN TEMP and continue until crystallization is complete
    - if beaten while still hot: form large crystals because of the rapid movement of molecules (they are far apart so less nuclei are formed and each one grows larger as temp. cools)
    - if cools properly: forms small crystals= creamy texture
    ** contact with rough surface/seeding from dust/extra sugar crystals= too rapid crystallization- larger crystals
7
Q

what is inverted sugar

A

def: equimolar mixture of glucose + fructose that is formed when sucrose (table sugar) is heated in the presence of an acid or enzyme invertase
- interfering agent
- acids uses: cream of tartar, vingear, molasses
- dependant on cooking time (too long= too soft candy, too little= coarse and grainy product

8
Q

2 ways measure dodenss of candies

A
  1. temp of the syrup using a thermometer (chech accuracy in boiling water first)
  2. cold-water test= measure the consistency of syrup when dropped in cold water (a drop of syrup is made to fall off the edge of a spoon into glass of cold water)
9
Q

6 stages of a sugar syrup

A
  1. thread: syrup will not harden (bind agent for fruit pastes) (106-112C)
  2. soft ball: for soft but firm candy like fudge, fondant, creams, maple…
  3. firm ball: caramels (118=120C)
  4. hard ball: divinity, taffy, nougat, marshmallow
  5. soft crack: hard threads form; will form very hard candy; butterscotch, toffee (132-143C)
  6. hard crack: brittle threads form; brittle,
  7. light caramel (honey-golden in color)
  8. dark caramel (deep redish-amber in color) (177C)
  • 8 each stage= associated with temp range
  • ** needs to let the syrup cool to the proper temperature before agitation begins: THE TEMP. OF THE CANDY SOLUTION AT THE TIME OF BEATING IS THE MOST INFLUENCAL FACTOR IN CRYSTAL SIZE
10
Q

caramelization

A

def: nonenzymatic browning involving a nubr of reactions that occur when sugar is heated
- facilitated with acid
- organic acids= froms when sugar decomposed
ex: use baking soda to the caramelized sugar for peanut brittle= soda + acids reacts so produce CO2= holes in the brittle
- equipment; cast iron skillet + wooden spoon

2 methods for caramel
DRY AND WET METHOD: only use sugar (no water like the wet method)
- WET: not stirred until water is evaporated + look like layers of bubbles because if not= crystallize

to prevent crystals to stick:

  1. oiling the sides of the pot
  2. brushing the side with water
  3. covering pot for couple of minutes to let steam form
11
Q

coffee + goal of brewing

A
  • good quality coffee= amber brown, clear of sediment, with a mild/brisk flavor
  • goal of brewing: extract max amount of caffein +falvouring substances while minimizing amount of polyphenols (tannins)
    2 ways to achieve goal of brewing:
    1. water contact with the ground is limited
    2. temp. not rise to boiling

different types:

  1. turkish cofee= strong + not respect the principles
  2. instant coffee= lacks the rich flavor of brewed coffee
  3. freeze drying coffee= improve flavors + cost..
12
Q

6 principles of coffee

A
  1. clean pot (create a bitter flavor during brewing)
  2. use correct ground for the different methods of brewing (too fine= too strong brew, too large= too weak
  3. medium strenght coffee: 15ml ground coffee/175ml eau
  4. coffee pot = filled 3/4 capacity for the best quality brew
  5. since coffee grounds absorb aroma from the brew= should be removed and discarded after the brew is prepared
  6. stroing fresh coffee in thermal carafe= preserves fresh taste ,storing in coffee maker= flavor deterioration
13
Q

tea (characteristics + different type)

A
  • processing of tea leaves= affect the flavor
    1. green tea: highly astringent + light in color
    2. black tea: full-bodied flavor and darker color when leaves are fermented as black tea
    3. oolong tea: partially fermented tea, flavor characteristics of both green and dark tea
  • over extracting tea leaves by prolonged steeping results in bitter beverage
  • adding lemon juice= lighter color+ changes pH
14
Q

tea tasting

A
  1. slurping the liquid up into the mouth frm the surface of the spoon (O2 mixes with the liquor, help to brings the flavours to life)
  2. with tea in the mouth, should breathe out through the nose (keep mouth closed) = called retro-olfaction perception
    then liquoir may be swallowed, allowed the taster to pay special attention to sensation on tongue
15
Q

tea descriptors (4)

A

For testing qualities = AROMA and ASTRINGENCY
1. AROMA: scent released form the leaf as a result of the brewing process
2 types:
- the fresh, clean or dull aspects that show style and quality of manufacture
- the floral, nutty or grassy descriptors correspond to the flavours that the palate will amplify

  1. ASTRNGENCY is a tactile taste felt as a dry, rough feeling in the mouth and contraction of tongue tissue. Involve formation of aggregated precipitates between tannins/polyphenols and proteins in salive
    - tannins positively influences the tase of tea (as well as coffee, cocoa, wine, beer)
    - tannins have a negative effect in immature fruit (bananas..)
  2. COLOR: from pale gold to dark purple-black
  3. CLARITY: describes degree of transparency or purity