Preservatives for maintaining microbiological quality

Question 1

What are classes of agent used for preservatives

Answer 1

Organic acids e.g. benzoic acid, sorbic acid
Parabens, esters of p hydroxybenzoic acid
Aromatic alcohols e/g/ benzylalchol
Substituted phenolic agents, Cholrocersol

Question 2

What is the challenge test (evaluation of preservatives)

Answer 2

assess activity with product in final container incoluate preserved product 10 to the 5 or 6 organisms per ml or per gram of product, incubate at prescribed temp, withdraw samples over 28 days,, preservative adequate if there is a decrease in viability,

Question 3

What are the factors affecting choice of preservative?

Answer 3

Intended application
No and type micro organisms present 
Safety, stability and cost 
Micro environment 
Properties of chemical agent

Question 4

What are the most likely contaminating organisms? ORAL PRODUCTS?

Answer 4

Bacteria: E.coli, S.aurues, P,aeruginosa
Fungi: Candida sp, other fungi