Unit 15 Cleaning Chemicals

Question 1

What is the purpose of cleaning?

Answer 1

Is to permanently remove all the soil from the surfaces of the plant to leave it in a condition suitable for use.

Question 2

What is the purpose of sterilising?

Answer 2

Is to kill any micro-organisms that remain on the internal surfaces of the plant after cleaning so the product is not contaminated. (mostly RTD’s)

Question 3

What would you use if the same equipment was being used for strong flavoured products or brown or white spirits?

Answer 3

Liquor flush is all that’s used to clean the plant.

Question 4

Give examples of products that require higher degrees of cleanliness.

Answer 4

Products that are sensitive to spoilage like beers, RTG’s and cream liqueurs.

Question 5

What is the definition of sterilisation?

Answer 5

elimination of all forms of life including microbial spores, mostly achieved with live stream at a minimum of 120C and a contact time of at least 15 minutes.

Question 6

What is the definition of hygiene conditions?

Answer 6

degree of cleanliness that eliminates all vegetative forms of life - mostly in liquid production and other beverage plants.

Question 7

What is the definition of condition of clean conditions?

Answer 7

Suitable for the removal of all soils but not all vegetative cells.

Question 8

What can growth control be affected by?

Answer 8

Limiting microbial growth by removal of nutrients or removal of protective materials

By removing all viable microbes by either total removal (sterilisation) or removal of vegetable cells only.

Question 9

What cycle do control measures follow?

Answer 9

Decontamination (cleaning)

Disinfection to prevent growth or eliminate viable microbes.

Sterilisation to prevent the growth of any surviving organism in product, eliminating spoilage.

Question 10

What are detergents?

Answer 10

Is a blend of chemicals which is put together to solubilise soil & remove it from the surface and ensure that it does not re deposit itself back onto the clean surface.

Question 11

How do detergents help the cleaning process?

Answer 11

Penetrating the soil

Dissolving the soil

Dispensing the soil

Carrying the soil away

Question 12

What is the purpose of sterilants?

Answer 12

they are formulated to kill microbes and bring micro organisms load to an acceptable level and work by:

Creating the conditions of temperature, pH, chemical or surface activity that can destroy micro organisms.

Question 13

What is always used as the medium for carrying detergents?

Answer 13

Water & it has a high surface tension.

Question 14

What do detergents contain to help surface tensions?

Answer 14

A substance that reduces surface tension which therefore increases the detergents wetting power.

Question 15

What happens when a substance is dissolved?

Answer 15

It becomes chemically bound into the liquid and the liquid is usually clear.
If soil can be dissolved in the detergent liquid, not only can it be removed from plant surface, it can be carried away easily.

Question 16

What are the 2 main types of soil that needs to be removed from the surface of a brewing and packaging plant?

Answer 16

Organic Soil = yeast protein, fat & sugar. Any detergent which will break it down is best to use.

Inorganic soil = scale and “stone”. Nitric acid or phosphoric acid is good for dissolving inorganic soil.

Question 17

What happens if not all soil is soluble?

Answer 17

Insoluble soil can be removed if “dispersed” so it can be carried away in the liquid.

Detergents will contain substances which help to disperse the soil & hold is in suspension so it can be rinsed away.

Question 18

What is important at completion of the cleaning cycle?

Answer 18

There is no detergent & accompanying soil remains on the plant surface.

It must be rinsed away.

Question 19

What is detergents made of?

Answer 19

The base of acids and alkalis, therefore chemical properties are acidic or basic.

Question 20

Alkaline detergents work better for what 2 reasons?

Answer 20

Organic soil tends to be more acidic in nature.

Basic detergents can hydrolyse organic polymer chains, which add to the easy removal of soil as smaller molecules,

Question 21

What are the four ingredients for detergents?

Answer 21

• Base material (acid or alkalis)
• Surface active molecules as wetting agents
• Chelatting agents or sequestrants
• floccuating agents (sometimes)

Question 22

Why are sequestrants or chelating agents added to detergents?

Answer 22

in order to soften water by grabbing metal ions like calcium or magnesium.

These metal ions bond dirt together.

Question 23

Why are surface active molecules added to detergents?

Answer 23

Act as wetting agents that assist in the penetration of dirt.

Question 24

Why are flocculating agents (sometimes) added to detergents?

Answer 24

to facilitate the easy removal of dirt by pulling dirt together in lumps - which is therefore easy to be removed.

Question 25

What are Caustic detergents not suitable for?

Answer 25

Cleaning aluminium tanks

Question 26

Whats the effects of caustic soda and what are some benefits/problems?

Answer 26

• Dissolves organic matter
  -Sterilises especially when hot

Does not rinse well
Cannot be used by hand
dissolves aluminium

Question 27

What are the effects of other alkalis and what are there benefits/problems?

Answer 27

Dissolves Organic Matter

Less Aggressive than Caustic soda.
very good dispersants

Question 28

What are the effects of oxidants and what are the benefits/problems?

Answer 28

Helps dissolve protein
Sterilises

Very coorcive unless at a High pH

Question 29

What are the effects of phosphates and what are the benefits/problems?

Answer 29

Soil removal

Very good rinsing properties.

Question 30

What are the effects of acids and what is the benefits/problems?

Answer 30

dissolves scale

corrosive in high concentrations
not denatured by CO2

Question 31

What are the effects of wetting agents and what are the benefits/problems?

Answer 31

reduces surface tension

may cause the detergent to foam.

Question 32

what are the effects of sequestering agents and what are the benefits/problems?

Answer 32

prevent formation of scale

expensive

Question 33

What are the 7 types of sterilant?

Answer 33

“halogens” like chlorine and iodine.

Formaldehyde

Ammonia

Hydrogen peroxide

peracetic acid

Ampholytic surfactants

Question 34

What would you use to sterilise transfer mains, filter mains and packaging mains?

Answer 34

Hot water or steam

amphoteric surfactants

peracetic acid

Question 35

What would you use to sterilise product vessels?

Answer 35

Amphoteric surfactants

peracetic acids

Question 36

What would you use to sterilise filtration plant?

Answer 36

hot water or low pressure steam

amphoteric surfactants

peracetic acid

Question 37

What would you use to sterilise the packaging plant?

Answer 37

hot water or steam

amphoteric surfactants

peracetic acids

Question 38

How long and at what temp does heat need to be held for, to be effective?

Answer 38

90C for 15 minutes.

Question 39

What what temperature and contact time will you achieve total sterilisation using steam?

Answer 39

120C for at least 15 mins.

But can be cleaned in 2-3 minutes for practicality purposes.

Question 40

Describe high pressure cleaning.

Answer 40

combines high pressure, high temperature and detergent.

Reaches areas that are difficult to clean.

minimises detergent uses.

Question 41

Describe foam cleaning

Answer 41

working solution is diluted with air.

small quantities of water is used.

foam is removed by rinsing with water.

Question 42

describe cleaning in place

Answer 42

allows systems, vessels, piping, valves, and other equipment’s to be cleaned without dismantling all or part of the items.