Part 1: Basic principles

Question 1

Critical knowledge to understanding unit operations and preservation

Answer 1

-Structure and composition of foods
-chemical, sensory, and nutritional properties
-types of microorganisms likely to be present in foods

Question 2

What does the chemical composition of foods determine?

Answer 2

-suitability of raw materials used during food processing of particular products
-sensory characteristics and nutritional value

Question 3

Important to remember

Answer 3

Understanding food composition enables processors to design new products while controlling sensory qualities during processing and storage

Question 4

Define carbohydrate

Answer 4

Generic term for a wide variety of chemicals that form the major part of dry matter in plants

Question 5

What is dry matter?

Answer 5

All components in plant and animal material excluding water

Question 6

Define monosaccharides

Answer 6

-The simplest form of carbohydrates (simple sugars)
-cannot be broken down further by hydrolysis

Question 7

Define Hydrolysis

Answer 7

Any chemical reaction where water is used to break down the chemical bonds present in a substance

Question 8

List the Monosaccharides

Answer 8

Glucose (dextrose)
Fructose
Galactose

Question 9

Define and list disaccharides

Answer 9

Two monosaccharides linked together
Sucrose (glucose + fructose)
Lactose (glucose + galactose)
Maltose (glucose + glucose)

Question 10

Facts about sucrose

Answer 10

-derived from sugar cane or beet
-highly soluble & sold as syrups due to its high osmolality
-used as humectant/preservative (to increase boiling point or reduce freezing point of foods)

Question 11

Define osmolality

Answer 11

A measure of how much one substance has dissolved in another substance

Question 12

Define humectant

Answer 12

A means to retain or preserve moisture

Question 13

What is the Maillard reaction?

Answer 13

A chemical reaction between sugars and amino acids to create melanoidins (golden brown color)

Question 14

What is the difference between molarity and molality?

Answer 14

Molarity is the total moles of absolute based on liters of solvent whereas molality is based on kilograms of solvent

Question 15

Why is molality used over molarity?

Answer 15

Molality is used because it’s value does not change with changes in temperature

Question 16

Where does lactose occur?

Answer 16

In milk

Question 17

How is lactose used in fermented milk products?

Answer 17

It is fermented by lactic acid bacteria

(Some people are deficient in lactase production which results in being lactose intolerant)

Question 18

Define fermentation

Answer 18

The chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence ( formulation of gas bubbles in a liquid by a chemical reaction)

Ex. The process of fermentation involved in the making of beer, wine and liquor in which sugars are converted to ethyl alcohol

Question 19

How is maltose formed?

Answer 19

-Formed by hydrolysis of starch
-Commercially used by malting grains, especially Barley, using beta-amylase either naturally occurring or added after production by Bacillus spp.