Food additives Flashcards
What are food additives?
Substances/chemicals added to food to make them either part of the food or to influence its structural/functional properties
- may be added intentionally/directly or unintentional/indirectly
What are food components that are NOT food additives? (12)
why?
- vitamins, minerals, amino acids
- salt, sugar, starch, spices, seasoning, flavorings
- agricultural chemicals and veterinary drugs
- food packaging materials
- salt, sugar are used from time immemorial so not a food additive
- starch: cannot say its a food additive for potato bc its all starch VS adding starch as a thickener = a food additive
difference between direct and indirect additives?
DIRECT:
- added to achieve structural and functional changes in food product
INDIRECT:
- added as a result of various domestic (ie spray cabinets with bug spray: residue can stay in cabinets), industrial (wood smoke, wild fire residues can be added to food materials) and agricultural practices (add pesticides)
3 main groups of direct additives? + functions
- food processing aids/functional additives: used in preparation of production of foods into desired finished forms
- food preservatives: help extend shelf-life of food material
- food quality enhancers: improve quality in terms of particular attributes
what are 2 broad categories of food processing aids? + subtypes?
FOOD TEXTURE IMPROVERS:
1. emulsifiers
2. thickeners
WATER BINDING AGENTS:
1. humectants
2. anti-caking agents
difference between emulsifiers and thickeners/stabilizers?
- give examples
EMULSIFIERS:
- ie: lecithin, mono and diglycerides
- emulsifiers are amphiphatic: have both polar and nonpolar ends –> added to 2 immiscible solvents (ie oil and vinegar) –> polar end binds to vinegar and non-polar binds to oil to form a stable product
- basis for making products like salad dressing and mayonnaise
THICKENERS/STABILIZERS:
- ie starch, gums, pectin, carboxymethylcellulose (CMC)
- can imbibe moisture –> when added to foods, they absorb moisture and swell to thicken the food
humectants vs anti-caking agents
- give examples
HUMECTANTS:
- bind and retain moisture in food to make them juicy/succulent
- ie polyhydric alcohols like sorbitol and glycerol, phosphates, polyphosphates
ANTI-CAKING AGENTS:
- absorb/withdraw water from food product to prevent clumping and to keep food material dry
- ie silicates, cornstarch
- ie: add rice in salt and sugar to keep them dry
what is sometimes added to scallops to make them swell so they appear bigger at supermarket?
polyphosphates!
- a humectant which is a water binding agent which is a food processing aid
Food processing aids:
ENZYMES:
- function
- 4 application examples
- 3 enzymes for _____ __________
- 2 enzymes for _______ ___ _______ _____
ENZYMES:
- transform raw materials into finished products
- ie: use invertase on sucrose to make invert sugar, glucose isomerase to make HFCS, rennin & proteases to make cheese, LOX for bleaching flour
- bromelain, papain and ficin as meat tenderizers
- amylases and pectinases for clarification of fruit juices
Food processing agents:
FOAMING VS ANTI-FOAMING AGENTS
- function
- uses what?
- used in which food products
FOAMING:
- enhances foam formation in food products to make them fluffy and airy
- proteins and peptides (egg white/albumin, milk powder) –> make bubbles + air gets trapped inside
- ice cream, frozen desserts
ANTI-FOAMING AGENTS:
- prevent foaming in food products
- octanol, parafins, oleic acid, silicone oil
- chicken nuggets, french fries, potato chips
Food processing aids:
ACIDS vs ALKALIS
ACIDS:
- provide sour flour + inhibit growth of bacteria/enzyme activity by decrease pH –> makes food milieu not conductive to proliferation of microorgs
- acetic acid, citric acid, phosphoric acid, lactic acid, malic acid, benzoic acid, sorbic acid
ALKALIS:
- leavening agents bc can release CO2 and increase volume of foods
- Na2CO3, NaHCO3, K2CO3, NH4HCO3, carbonates and bicarbonates
benzoic acid and sorbic acid
- function?
- what category of food additive?
- used in salt or acid form?
- inhibit microbial growth
- acids! as a food processing aid
- GOOGLE ANSWER
Food processing aids:
BUFFERS
- function
- examples
- specific example for salt
- criteria for selecting a buffering agent (3)
- precent acidic and alkaline changes in food products –> maintain pH to add/preserve food flavors AND oto stabilize food product
- phosphates, citrates, calcium hydroxide, borates, lactate, glycine
- KI added to salts to prevent goiter –> Ca(OH)2 added to iodized salts to maintain pH stable to prevent KI from breaking down to I2 which will impart a brownish/orange color to the salt
1. must not alter their characteristics traditionally associated with food material
2. must be readily available
3. not too expansive
2 main functions of food preservatives + subtypes
CONTROL MICROBIAL GROWTH
1. fermentation
2. humectants
3. acids
FOOD STORAGE EXTENDERS:
1. antioxidants
2. enzyme inhibitors
3. antimicrobial agents
4. modified atmosphere packaging (MAP)
5. additives that can be added to food packaging materials
3 ways to control microbial growth? + process/examples
FERMENTATION:
- produces intermediates/produces like acetic acid, proprionic acid, lactic acid, ethanol that can prevent spoilage by inactivating or destroying microorganisms
HUMECTANTS:
- lower water activity to make food milieu non conductive to growth and proliferation of microorgs
- ex. sugars, salts, alcohols
ACIDS:
- decrease pH to render the milieu non conductive to both enzymes and microorgs –> the 2 causative agents of food spoilage
- phosphoric acid, citrate, lactate, acetate, benzoate, sorbate