Question

What are indicator organisms?
(A) Organisms which cause disease
(B) Organisms which prevent disease
(C) Which analyze sample
(D) None of the above

Answer 1

Indicator organisms are used to assess overall sanitation or environmental conditions that may indicate the potential presence of pathogens of food safety concern. The term indicator organism has been used for nearly a century to check the microbiological status of food production and food controlling system. The most common indicators used for foods and drinking water are coliforms, Enterobacteriaceae, E.coli , Listeria species, and the molds and yeasts.

Complete answer:
Organisms which cause disease: Indicator Organisms are not necessarily pathogenic. Indeed, when consumed at a high enough level, certain Indicator species such as mold, can be toxic.

Organism which prevent disease: Most bacterial species are non pathogen, some are even beneficial to environmental processes. There are about hundred species of bacteria that cause infectious diseases in human and can spread through water air soil and physical contact. Non-disease bacteria reside on the surface of vertebrates and invertebrates as commensals.

Analyzing sample: Indicator Organisms are used as markers whose presence in number when exceeds given numerical limits indicates the possible occurrence of ecologically similar pathogens, inadequate processing and the quality of raw materials.

Indicator species perform two major roles in food testing.
Quality: Indicator organism used to assess spoilage, example: mold growth
Safety: The presence of indicator species can signal the presence of fecal contamination in the environment and can signal environmental conditions which are hospitable to the growth of pathogens.
Thus we can say that indicator organisms are used as sample analyzers.

So, the correct option is C.

Note:
Current test methods for pathogens are costly and time-consuming. Indicator species can be tested for with relative ease, and act as an early-warning system that can signal contamination issues and the need for further diagnostic testing vermox cena. Depending on their application, the major factors considered in classifying an organism as an indicator may include:
Their strong association with fecal contamination
Their cohabitation with pathogens of concern
Simple and efficient testing procedure.

Following factors should be kept in mind when selecting an indicator for a particular purpose:
Their presence should suggest a faulty practice or a potential for spoilage.
Stability or survival of indicators should not be less than the hazard organism.
Indicators should have stable identifiable characteristics.
Growth characteristics of indicators should be similar or faster than spoilage organisms. Method of detection should be easy, reliable, inexpensive, rapid, and sensitive.