Intro to analysis Flashcards
Why do we analyze food?
- Compliance with legal and labeling requirements, 2. Assessment of product quality, 3. Determination of nutritive value, 4. Detection of adulteration, 5. Research and development
What are the types of samples analyzed?
- Raw materials, 2. process control samples, 3. Finished product, 4. competitor’s sample, 5. Complaint sample
Properties of food analyzed
- Composition, 2. structure, 3. physiochemical properties, 4. sensory attributes
Molecular structure
1-100nm, type of molecules present, their 3D structures, and their interactions with each other.
Microscopic structure
10nm-100microm, Regions in a material where the molecules associate to form discrete phases (ex. emulsion droplets, fat crystals, protein aggregates, small air cells)
Macroscopic structure
> 100microm, can be observes by the unaided human eye (ex. sugar granules, large air cells, raisins, chocolate chips)
Physiochemical properties determine…
- perceived quality, 2. sensory attributes, 3. behavior during production, storage, and consumption
Optical properties
Determined by the way foods interact with electromagnetic radiation in the visible region of the spectrum.
Rheological properties
Determined by the way that the shape of the food changes, or the way that the food flows, in response to some applied force
Stability
The ability to resist changes in its properties over time
Examples of chemical stability
fat rancidity, non-enzymatic browning, pigment formation
chemical stability
A change in the type if molecules present
Physical stability
A change in the spatial distribution of molecules
Examples of physical stability
Creaming in milk, emulsions
Biological stability
A change in the number of microorganisms present in a food with time
