WATER AND FOOD MICROBIOLOGY

INTRODUCTION

• Name : Ghazala Shaheen• Serving as Sr. Technologist 1 • Clinical Microbiology

WATER CULTURE TESTING

• INTRODUCTION:

Water is one of our most precious & natural

resources without sufficient quantity. Water is

the most abundant compound used by all life.

The requirement for a public water supply are.

1. It shall contain no organism which cause disease

2.It should be clear and colorless.

3.It should be good testing free from odours and

preferably cool.

Contd…

•Full examination of water supply embodies for time of investigation topographical ,chemical, biological and bacteriological each having its uses.• All the above mentioned investigations are important but we are concerned with bacteriological examinations which is particularly important because it still offers the most sensitive test for the detection of fecal and therefore potentially dangerous.

TECHNIQUE OF SAMPLING

Sample Bottles:

Sterile bottles should be provided by the

laboratory performing the examination & should be used exclusively for bacteriological purposes neutralization of chlorine for low concentration of chlorine & PH values normally occurring in water supply.

TECHNIQUE OF SAMPLING (contd)…

Sodium thiosulphide added in empty containers should neutralize up to 5mg/l of free and combined residual chlorine and as no significant effect on the coli form of E.Col; content of unchlorinated water on storage so it is therefore recommended that at least this level of thiosulphate should be added to all bacteriological sample bottles before they are sterilized.

OPENING & FILLING OF SAMPLE BOTTLES

1. Keep the sample bottle unopened until the moment it is required for filling.

2. Never rinse out a bottle before taking a sample loosen the string or rubber band holding the cover in position. Hold the bottle by the base in one hand & remove the stopper cover together with the other hand.

3. Retain the stopper & cover in the hand whilst the bottle is filled & replace them immediately.

4. Finally secure the cover.

BACTERIOLOGICAL EXAMINATION OF DRINKING WATER

For several reasons monitoring for the pressure of the specific pathogenic bacteria, viruses and other agents in water is impracticable & indeed unnecessary for routine control purposes, any pathogenic microorganism present in water are usually greatly outnumbered by & in general flora of contaminated water especially when it is heavily polluted.

Selective media are required for isolation & subsequent identification of the organism involves biochemical & other tests for the detection of certain commenced intestinal bacteria especially E.Coli & other coli form bacteria. Bacterial examination of water consist of different pathogens. They are

• Total colony count• Total coli form• Fecal E.Coli• Fecal Strept

WATER CULTURE MEDIA

We have used different media for water culture testing

• TGT For coliform• EMB For F.E.coli• Bile For F.Strept• CMA For Pseudomonas

FOOD MICROBIOLOGY

Food microbiology is on the detection & analysis of

food borne spoilage micro organisms.

Food microbiology is the study of food micro

organisms, how we can identify & culture them, how

they live and how some infect and cause diseases.

EDDY JET 1

EDDY JET 2

PROCESSING OF FOOD SAMPLES

Two types of food samples we have process by two different methods.

• Raw Food• Cooked Food Raw food have processed by poured plate method &cooked food process by spiral plate method. Important

pathogen which spoil the food cause different food borne infection & food borne illnesses.

Indicator organisms which cause food born infection are.

• 1. E.coli E.coli can cause severe cramps & diarrhea. E.coli leading cause a bloody diarrhea. E.Coli infection come from

Eating uncooked ground beef. Drinking contaminated (impure) water. Drinking unpasteurized (raw) milk.

• Staphylococcus Aurous:

Staphylococcus aurous common cause of bacterial food

borne disease world wide. Symptoms include vomiting &

diarrhea that occur shortly after ingestion of

staphylococcus aurous toxin contaminated food.

Staphylococcus aurous is a leading cause of gastro

enteritis resulting from the consumption of contaminated

food.

• Salmonella:-

Salmonella is one of the most common cause of

acute gastroenteritis and is usually found in poultry,

eggs unprocessed milk & in meat and water.

Salmonella bacteria attack the stomach & intestine.

In some serious cases bacteria enter the lymph treats

which carry water & protein to the blood.

• Listeria Monocytogens:- These are bacterial pathogens & cause food illness. The

disease is called “Listerious”.• Shigella:- It is caused by poor hygiene and easily passed from

person to person & from infected individuals to food items. It causes an estimated diarrhea, sources include salad, unclean water& any food handled by someone who is infected with the bacterium.

• Vibrio:-

Vibrio causes gastroenteritis, wound infection &

severe blood stream infection.