jam

Question 1

what does the main ingredient of the jam do?

Answer 1

adds the flavour and colour of the jam

Question 2

what is pectin?

Answer 2

a naturally occurring ingredient in fruits which allows the jam to become set.
- the amount of pection varies from fruit to fruit
- it traps liquid and bursts which give the jam its consistency and texture

Question 3

what role does the sugar play in the jam?

Answer 3

its main role is to absorb as much moisture to make the environment more unfavourable for the growth of microorganisms.

it also is the sweetner of the jam

Question 4

what role does the lemon juice play in the jam?

Answer 4

its main role is to make the jam acidic, making the environment more unfavourable for the growth of microorganisms

Question 5

why is the jar put in the oven at a low temperature?

Answer 5

• to sterilise the jar, killing off all microorganisms with the heat
• low temperature (120) makes sure the jar doesn’t break while stilling killing all microoorganisms

Question 6

why are funnels useful in the jam making process?

Answer 6

it allow a clean and easy method of transporting the jam into the jar

Question 7

list the 4 principles of preservation

Answer 7

1. control of temperature
2. control of moisture
3. control of pH
4. exclusion of air

Question 8

describe how control of temperature was incorporated in the jam making process

Answer 8

• heat was used to boil and simmer the jam
• once the jam is opened from the jar, putting it in the refrigerator will slow the growth of microbial activity
• cooking the jam at boiling point kills all microorganisms which could have been present on any utensils/ingredients
• heat used to sterile the jar

Question 9

describe how control of pH was incorporated in the jam making process

Answer 9

• the lemon juice made the jam acidic, making the environment more unfavourable to microbial growth

Question 10

describe how the exclusion of air was incorporated in the jam making process

Answer 10

• the jar is tightly sealed to exclude as much air as possible. this creates a vaccum, stopping any extra air from entering the jar
• once it’s put in the fridge upon opening the jar, you close off any external air from entering the fridge, thus the jam as well.

Question 11

describe how control of moisture is incorporated in the jam making process

Answer 11

• a large amount of sugar is used to absorb all the moisture, making it an unfavourable environment for microbial growth