Bacteria need optimum
conditions for them to reproduce into large quantity and be able to able to
cause food spoilage. The optimum temperature for bacteria to thrive and survive
ranges with that of the normal body temperature of humans (36.6oC, 98.6oF).
This therefore means that when food are keep
and a very high
conditions for them to reproduce into large quantity and be able to able to
cause food spoilage. The optimum temperature for bacteria to thrive and survive
ranges with that of the normal body temperature of humans (36.6oC, 98.6oF).
This therefore means that when food are keep
and a very high
temperature or very low temperature, the growth of
material is restricted therefore hindering them from reproducing to a higher
number that can lead to food poisoning. Bacteria cause food poisoning if they
are present in a very large number in food and for them to reproduce to a large
number in food, the condition must be favourable.
Some bacteria tolerate the
presences of salt better than others and we take advantage of this when curing
meats. All of them hate cold, and round 32oF, (1000C)
they become lethargic and dormant when the temperature drops lower keeping them
at lower temperatures does not kill them, but only stops them from multiplying.
Once the conditions are favorable again, they will wake up and start growing
again. As temperature increases above 600C (1400F), it
kills bacteria thereby hindering their ability to cause food poisoning. Most
bacteria need oxygen (aerobic), others thrive without it (anaerobic).
presences of salt better than others and we take advantage of this when curing
meats. All of them hate cold, and round 32oF, (1000C)
they become lethargic and dormant when the temperature drops lower keeping them
at lower temperatures does not kill them, but only stops them from multiplying.
Once the conditions are favorable again, they will wake up and start growing
again. As temperature increases above 600C (1400F), it
kills bacteria thereby hindering their ability to cause food poisoning. Most
bacteria need oxygen (aerobic), others thrive without it (anaerobic).
Whatever the type of bacteria,
the follow are the condition necessary for their survival and their ability to
cause food poisoning:
the follow are the condition necessary for their survival and their ability to
cause food poisoning:
1. Oxygen
2. Temperature
3. Water
4. Food /nutrients
5. pH
1. Oxygen: Depending on the nature of the bacteria, the presence
or absence of oxygen determine their ability to cause food poisoning. Some
bacteria require oxygen to grow (aerobes) while others can grow only in the
absence of oxygen (anaerobes). For those that require oxygen to grow, all other
condition being equal, the presence of oxygen will help them to reproduce and
cause food poisoning while the absence of oxygen will stop them from causing
food poisoning.
or absence of oxygen determine their ability to cause food poisoning. Some
bacteria require oxygen to grow (aerobes) while others can grow only in the
absence of oxygen (anaerobes). For those that require oxygen to grow, all other
condition being equal, the presence of oxygen will help them to reproduce and
cause food poisoning while the absence of oxygen will stop them from causing
food poisoning.
2. Temperature: Most pathogenic bacteria grow at these micro-
organisms grow at higher temperature such as 1100C – 1500F.
Temperature is most widely used method of controlling bacteria growth. Bacteria
grow slowly at temperatures below 450C and thermal destruction
occurs at temperature danger zone – between 450C and 1400F
many bacteria are controlled. Bacteria in general are capable of growing over a
wide range of temperatures and are usually classified according to the
temperature at which they grow. Psychotropic bacteria are those that are
capable of growing at 320F – 450F but their optimum is from 680F to
86oF. They cause spoilage in foods stored under refrigerator.
Several pathogenic bacteria are psychotropic – yersina and listerina mesophilic
bacteria. Most bacteria are capable of
growing at about 60oF and belong in this group.
organisms grow at higher temperature such as 1100C – 1500F.
Temperature is most widely used method of controlling bacteria growth. Bacteria
grow slowly at temperatures below 450C and thermal destruction
occurs at temperature danger zone – between 450C and 1400F
many bacteria are controlled. Bacteria in general are capable of growing over a
wide range of temperatures and are usually classified according to the
temperature at which they grow. Psychotropic bacteria are those that are
capable of growing at 320F – 450F but their optimum is from 680F to
86oF. They cause spoilage in foods stored under refrigerator.
Several pathogenic bacteria are psychotropic – yersina and listerina mesophilic
bacteria. Most bacteria are capable of
growing at about 60oF and belong in this group.
3. Water: It is a very common practice to dry food items such
as meat or fish to preserve them. Bacteria need water to dissolve food they use
for energy and growth. Water allows the food to get into the cells, is used for
the many chemical reactions necessary for life and growth, and allows waste
products to escape. This principle is due to the understanding that drying the
food item removes moisture (water) from it thereby preventing it from poisoning
since bacteria cannot survive without moisture.
as meat or fish to preserve them. Bacteria need water to dissolve food they use
for energy and growth. Water allows the food to get into the cells, is used for
the many chemical reactions necessary for life and growth, and allows waste
products to escape. This principle is due to the understanding that drying the
food item removes moisture (water) from it thereby preventing it from poisoning
since bacteria cannot survive without moisture.
4. Food/Nutrients: All bacteria require energy derived from substances
that contain items such as sugars, starch, protein, fats and others compounds
provide the nutrients. The presence of these sources of energy encourages the
growth of bacteria to a very high level that can enable them to cause food
poisoning, while the absence of these conditions will stop the bacteria from
reproducing.
that contain items such as sugars, starch, protein, fats and others compounds
provide the nutrients. The presence of these sources of energy encourages the
growth of bacteria to a very high level that can enable them to cause food
poisoning, while the absence of these conditions will stop the bacteria from
reproducing.
5. PH: Different bacteria need different pH
for them to survive and reproduce in other for them to cause food poisoning. Most
bacteria grow well at neutral pH which is 7, but a lot of them can
tolerate a pH range from 4.5-10.0. At this pH range,
bacteria can cause food poisoning but pH higher or lower than the
set range will not be favourable for bacteria to thrive. The pH of a
substance is measured with a pH which has a scale of 0 to 14 with 7 being neutral. PH is a term
used to determine the acidity or alkalinity of a substance. If the PH value is below 7, the
food is classified as acidic. And when it is above 7 it is classified as an
alkaline.
for them to survive and reproduce in other for them to cause food poisoning. Most
bacteria grow well at neutral pH which is 7, but a lot of them can
tolerate a pH range from 4.5-10.0. At this pH range,
bacteria can cause food poisoning but pH higher or lower than the
set range will not be favourable for bacteria to thrive. The pH of a
substance is measured with a pH which has a scale of 0 to 14 with 7 being neutral. PH is a term
used to determine the acidity or alkalinity of a substance. If the PH value is below 7, the
food is classified as acidic. And when it is above 7 it is classified as an
alkaline.
