Technical challenges : part 6 / 7 : lipids Flashcards
what are the function of lipid ingredients ?
- lubricant and tenderizer 2. heat exchange medium 3. carriers of fat soluble vitamins 4. textual ingreidents of emulsions 5. contribute to mouthfeel and flavor 6. emulsifier and surfactant
what is the difference between surfactant and emulsifier
emulsifier : will form the emulsion surfactant: will stabilize the emulsion and form the emulsion
what are the 6 properties to which we need to be carfull when selecting the appropriate lipid ingredient
1-nutrtional profile 2- flavor profile 3- crystallization behavior 4- oxidtive stability 5- bulk physicochemical properties 6- oil quality
*what are the two ways lipids can contribute to the flavor of a food
directly indirectly
What is the directly way that a lipid can contribute to the flavor of a food
by having flavor components inside the oil that will give a flavor to the food
What is the indirect way that a lipid can contribute to the flavor of a food
the chosen oil will affect the solubility and availability of the flavours inside the food it is added to
the melting point will increase with the ___ and ___
chain length and the saturation.
in lipids, the liquid to solid transition is called ____
crystallization
what is the crystal form with the best textural properties
beta prime
What are the factors that will influence the morphology of crystals?
1- internal factors (molecular structure, composition and interaction) 2- external factors (temperautre-time profile, agitation and impurities)
large crystals are ___ in the mouth
grainy
small crystals cause ___ sensation in the mouth
cooling
if the temperautre is decreasing rapidly, the crystals will be more ____
grainy
what are the factors that influence the oxidation of lipids
1- metals 2- oxygen 3- presence of light
what are the three caracteristics that lipids must have in order to enhance the formation and stability of emulsions
1- rapidly absorb to the surface of the freshly formed emulsion dropplets 2- must reduce the interfacial tension 3- must form an interfacial layer that prevent the aggregation of droplets
t or f : if you don’t reacht he critical concentration, you won’t have emulsifying properties
true
true or false : both the emulsifier and the surfactant will reduce the surface tension between the two phases
true
what are the 4 ways to stabilize an emulsion
1- electrostatic stabilization 2- steric stabilization 3- particle stabilization 4- multilayer stabilization
how is measured the surface activity ?
the ratio of hydropilic to lipophilic groups = hydrophile - lipophile blanance HLB
what is the formula HLB ?
HLB = 7 + total(hydrohilic group number) - total(lipophilic group numbers)
when the HLB is between 10-12, the emulsifier is hydrophilic or hydrophobic?
hydrophilic
when the HLB is between 3-5, the emulsifier is hydrophilic or hydrophobic?
hydrophobic
if the HLB is between 7-9, how are the surface activity properties
very high but there will be coalescence
What are the drawbacks of the HLB?
1- don’t take into acount the functional properties of the surfactant in various environments 2- the HLB depends on the oil type 3- no information on the type or amount of surfactant
