nanotechnology Flashcards Preview

Food Science 210 > nanotechnology > Flashcards

Flashcards in nanotechnology Deck (24):
1

the application of nanoscience to develop new materials and products, involving manipulation of matter at nanometre scale

nanotechnology

2

the study of material and processes on nanometre scale

nanoscience

3

nanotechnology processing examples?

nanoscale rxn engineering, heat/mass transfer, homogenization, sel-assembly

4

nanotechnology food safety/biosecurity examples?

nanosensors, nanotracers

5

nanomaterials examples?

nanoparticles, nano-emulsions, nanocomposites, nanostructured materials

6

example of "old" nanotechnology?

Faraday's gold, DNA structure discovery, drug delivery systems

7

examples of nano in food?

casein micelles and submicelles, fat crystal network

8

how is nanotech used in food packaging?

nanocomposites (strength, barrier), active packaging (anti-microbe), intelligent packaging (sense enviro)

9

nanocomposites made up of:

polymer matrix reinforced with nano-filler (fibre, platelet, particle with at least one dimension in nanometer scale)

10

examples of nanofillers?

layered inorgnic solids/clays like MMT (montmorillonite)

11

examples of bio-polymers:

polysacc, proteins, synth biopolymers (polylactic acid)

12

types of nanocomposites between polymers and layered silicates:

phase separated, intercalated, exfoliated

13

how is nanocomposite made?

polymer pellets+MMT powder-->extruder-->cooling roll-->solid sheets-->thermoforming thru pressing/drawing

14

how to calculate tortuosity factor?

= actual travel distance by penetrant / shortest travel distance in absence of any barrier

15

why use nanocomposites in food packaging?

^ moisture sensitivity, better barrier, flexibility, ^ thermal stability

16

is a higher Tortuosity factor better?

yes, has higher barrier properties

17

type of nanocomposite that has largest tortuosity factor?

exfoliated

18

how is nanolaminated emulsion created?

O/W emulsion stabilized by - charge protein, + charged biopolymer added to deposit on - charge droplet, coat w/ another - layer

19

by decreasing size of droplets, liquid can become solid _____

nanogel

20

significant increase in ___ content was found in vegetables wrapped in packaging materials made of ____ nanocomposites

silicon; MMT (montmorillonite)

21

smaller nanoparticles, ____ migratability

higher

22

___ nanoparticles become easily trapped in cationic charged mucus layer of GI, while ___ particles can escape

cationic; anionic

23

feeding rats with gold nanoparticles led to deposition of metals in:

kidney, liver, brain, other organs

24

potential toxicity of nanoparticles is based on?

oxidative stress it causes in cells-->potential for cancer, CNS, Parkinson's, Alzheimers (smaller particles is more harmful); influence GI (insoluble), damage DNA (metal oxide)-->depend on chem composition