Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Food Chemistry 2 > Food Additives > Flashcards

Food Additives Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Chemistry flashcards Gourmet Food flashcards Periodic Table flashcards Chemistry 101 flashcards Organic Chemistry 101 flashcards
1
Q

differentiate direct and indirect food additives

A

direct (intentional): deliberately adde to achieve a desired affect

indirect (incidental): added unintentionally as a result of various agricultural, environmental and domestic practices

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the 3 main groups of direct food additives?

A
  1. food processing aids and functional additives
  2. food preservatives
  3. food quality enhancers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are emulsifiers?

examples?

A
  • type of direct food additives (food processing aid)
  • amphiopathic molecules
  • able to bring aqueous and non-aequeous phases together to form a stable emulsion
  • examples: mono and diglyerides, lecithin, mustard powder
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are thickeners or thixotropic agents

examples?

A
  • type of direct food additive (food processing aid)
  • added to foods to add body or make product thicker
  • ex: starch, gums, pectin, CMC, whey proteins, sugars
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are water binding agents? what types are there?

A
  • type of direct food additive

- types: humectants and anticaking agents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are humectants? what is their function? examples?

A
  • type of water binding agent and type of direct food additive (food processing aid)
  • function: makes food product retain moisture in food
  • ex: phosphates, polyphosphates, glycerol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what types of foods are humectants usually used for?

A

meats (to make it tender and juicy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are anticaking agents? functions? examples?

A
  • type of water binding agent and type of direct food additive (food processing aid)
  • function: absorbs moisture from products (such as sugar and salt) to prevent them from going soggy)
  • eg. silicates and cornstarch
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what re enzymes used for meat tenderizing?

A

bromelain
papain
ficin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are enzymes used for clarification of fruit juices?

A

amylases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are foaming agents?

A
  • type of direct food additive (food processing aid)
  • used in same beverages and desserts
  • function: produces stable foams or makes product fluffy and lighter
  • ex: egg white and milk powder
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are anti-foaming agents?

A
  • type of water binding agent and type of direct food additive (food processing aid)
  • function: used to destabilize foam in products
  • eg: fatty alcohols, veg oils, silicone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are acids (as a direct food additive)?

A

eg. acetic and citric acid

function: flavor and texture improvement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are alkalis (as a direct food additive)?

A

function: raising dough volume in baking

eg. NaHCO3 as a leavening agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are buffers?

A

function: added to KI in table salt to stabilize KI and prevent breakdown
eg. Ca(OH)2 used to stabilize KI in iodized salts. Ca(OH)2 is alkaline and KI is stable in alkaline millieu

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the main uses of food preservatices?

A
  1. stability to reduce spoilage due to microbial activity and naturally present enzymes that break down substrates to form products that are undesirable/desirable
  2. safety: to avoid toxic substances produced by microorganisms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what kind of products can microorganisms produce?

A

toxic

autolytic products from enzyme action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

how do food preservatives control microbial growth?

A 
fermentation
humectants
diret addition of acids
gas sterilants
synthetic metabolic inhibitors
inorganic compounds
antioxidants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

how do food preservatives control microbial growth by fermentation?

A

by producing acids or alcohols that can inhibit enzymatic activity

acids (eg. pyruvic, lactic, citric) can control microbial activity by:

  1. lowering the pH to use enzymes to denature
  2. act as a metal chelator to inhibit enzyme activity

alcohols can control microbial activity by dehydration

20
Q

how does alcohol control microbial activity?

A

by dehydration

eg. If you add 1g enzyme to 10mL H2O vs adding 1g enzyme to 10mL H2O + 2 mL ethanol. ethanol is miscible with water and some of the molecules will be pulled away so not all of 10mL water is available for the enzymes. this reduces water activity which decreases enzymatic activity

21
Q

how do humectants control microbial growth?

A

by reducing water activity which impacts enzymatic activity

eg sugars, slats and alcohol

22
Q

how does direct addition of acids function as a food preservative?

A

reduces pH = reduces enzymatic activity = reduces microbial growth

23
Q

why do some acids act as anti oxidation?

A

due to metal chelation

24
Q

how do gas sterilants function as a food preservative?

A

cleans processing equipment to get rid of microorganisms

25
Q

what is lodophor, chlorine and methylbromide?

A

gas sterilants

26
Q

how do synthetic metabolic inhibitors function as a food preservative?

A

they are used in packaging materials to act on microorganisms and control microbial growth

27
Q

how do sulfites function as a food preservative?

A

sulfites are inorganic compounds used to prevent color formation in crustaceans and vegetables

28
Q

how to nitrites function as a food preservative?

A

nitrites are are inorganic compounds used to prevents growth of microorganisms

29
Q

what are examples inorganic compounds used as food preservatives

A

sulfites and nitrites

30
Q

what are antioxidants used in food preservation

A 
vit E
vit C
EDTA
citrate
propyl gallate
SO2
31
Q

how are antioxidants use in food preservation?

A
  1. storage life extenders
  2. prevents oxidative damage caused by exposure to air and light (which causes oxidative rancidity)
  3. emulsifiers: hols different phases of a food product together as a stable emulsion
32
Q

what are flavoring agents? what are they used for?

A
  • type of food quality enhancer
  • imparts flavor to food materials

2 types:

  1. natural: sugars, salts, spices, protein hydrolysates
  2. artificial: aspartame
33
Q

what are organic flavors

A
  • type of food quality enhancer

functions

  1. extracts natural flavors (eg cocoa, coffee, tea)
  2. fermentation (eg production of MSG)
  3. chemical synthesis (eg vanilla)
34
Q

describe the production of MSG

A
  • source material is eaten by microorganism
  • microorganism grows and produces more MSG
  • MSG is eventually released into medium
  • MSG recovers and crystallized
35
Q

what is the chemical synthesis of vanilla?

A

hydroxybenaldehyde to vanillin

methoxylation reaction

36
Q

what are three nutritional additives?

what are their functions?

examples of each?

A
  1. restoration additives: replaces components lost during processing (eg addition of vit C to canned tomato juice)
  2. enrichment additives: added to correct for deficiencies in a food product (eg. Fe in flour)
  3. fortification additives: added to food beyond normal level to address health or dietary issues
37
Q

what are 3 criteria used for policy on food additive use?

A
  1. must be safe for continuous use:
    - tested with 2 experimental animals
    - short and long term studies
  2. must not be used to deceive the consumer:
    - additive must not be used to mask defects in food products
    - adulteration, counterfeiting, misbranding
    - eg use of sulfites to reverse discolouration of fruits and veg
  3. must be used to the consumer’s advantage
    - must improve or maintain nutritive value, quality, acceptability and quantity of the food product
38
Q

in testing safe use of food additives, describe short term and long term studies?

A
  • must test with 2 experimental animals
  • must not cause harm to consumer over entire period of use
  • data used to determine the ADI (acceptable daily intake) of that additive for humans

short term:

  • animals observed daily for appearance and behaviour
  • weekly for feed consumption, body weight changes and organ function

long term:

  • offspring: stillbirths, litter size, weight at birth, sex ratio, fetal malformations, growth rate, survival data
  • on parent animal: fertility, lactation, incidence of tumors
39
Q

what is ADI

A

acceptable daily intake

one hundreth of the highest level of the additive that caused no harmful effect in experimental anima

40
Q

what are food colors?

A

compounds used to enhance appeal or acceptability of foods to consumers

41
Q

what are the categories of food colors

A

natural

synthetic

42
Q

what are two forms of certified food colors?

A
  1. water soluble:
    - dyes
    - sold as powders, granules and liquids
  2. water insoluble
    - lakes (Al or Ca salts of dyes)
    - ideal for coloring fatty food products
    - marketed as pastes and dispersions
43
Q

what are uncertified food colors

A

derived from platn, animal, microbial and mineral sources

44
Q

what are permitted food colors

A

varies from country to country

most countries don
t permit use of these substances in unprocessed foods

45
Q

what is criteria used for choice of dyes?

A
  1. composition of formulation
  2. processing conditions
  3. packaging
  4. shelf life requirements

Food Chemistry 2 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions