Etiket Arşivleri: indicator

Indicators in Food Microbiology

Indicators in Food Microbiology

Bacterial Groups Relevant to Food Microbiology

In Unit 1 we classified bacteria accordingly:

 Good (Beneficial)
 Bad (Spoilage)
 Very Bad (Pathogenic)

The primary interest in food microbiology is producing safe food with adequate shelf life


 Looking for specific bacteria that cause spoilage or food-borne illness is like looking for a needle in a haystack

 An indicator (index) in food microbiology is needed to confirm that the food is safe and has adequate shelf life

• Provide a gauge of product shelf life
• Highlight potential hazards
• An assessment of the previous history of food product
• Evaluation of the efficacy of control measures to prevent and/or inactivate microbial activity

Spoilage Indicators

Types of the bacterial counts will depend on the nature of the product

• Total Aerobic Count
• Psychrotrophic Count
• Lactic acid bacteria
• Yeast and molds

Laboratory‎ > ‎Acid – Base Titration

An acids-base titration is used to determine the unknown concentration of an acid or base by monitoring its neutralization reaction with a standard of known concentration in the presence of an indicator. For example, a base of unknown concentration may be titrated with an acid standard of known concentration or the reverse. The endpoint is the point of the acid-base titration in which just enough of the standard solution has been added to completely neutralize the solution of unknown concentration. Indicators are used to signal this point of the titration, and are generally selected according to the type of titration (strength of acid and based used in the titration). When the endpoint of the titration has been reached, one drop of standard solution past the endpoint will result in a color change of the indicator.