Carbohydrates lecture 3

Question 1

Bulking

Answer 1

The purpose of this is to provide additional mass and volume to a food product when the ingredients themselves are not enough to supply enough mass and volume for packaging. Bulking can also enhance food qualities like dispersion of ingredients and moisture stablization.

Question 2

crystalline vs. noncrystalline

Answer 2

Crystalline products are concentrated with solutes such that when they are exposed to moisture their water activity slowly increases until it reaches it’s deliquence point where it exponetially increases. The reason for this is because it is difficult for water to enter a food product until reaches a certain point and once it does the water begins to dissolves all the solutes present in the food allowing it to be more and more mobile thus increasing aw. In a noncystalline amorphous solid not as many solutes are present and so the aw increases as water gets in between particles and fills up the holes. Then it levels off as there are no more holes to fill, and increases again when the mositure increases to the point where it can dissolve more and more solutes.

Question 3

Dispersion and hydration

Answer 3

In order to dissolve particles you need to:

1. Disperse powder into aquaous env.
2. The particles will swell by absorbing H20 molecules
3. The surrounding material begins to erode until all of the material is dissolved in the solution

Question 4

The process of gelation

Answer 4

The viscosity rises as the particles begin to swell and reach a maximum. As the particles erode the viscosity declines to create a solution.

Question 5

Viscosity

Answer 5

Long polymers use the space around them to sweep in a circular manner and when they collide with other polymers doing the same thing they create friction which leads to an increase in viscosity. Viscosity can be reduced by hydrolyzing the molecule into multiple molecules or if the molecule is branched because they will occupy more volume and less space will be there to sweep.

Question 6

Rheometer vs. Brookfield viscosmeter

Answer 6

Rheometer is better because it can measure a newtonian fluids, shear thinning fluids and thixotrophic fluids.
Newtonian fluids: