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What conditions are most favorable for microbial food production? - Coggle…
What conditions are most favorable for microbial food production?
Dependent variables
Methods of mearusing the dependent variables: using a measuring cylinder and a weight.
the growth of the yeast
Independent variables
Method of changing independent variables: measuring different sugar weight using a scale.
The amount of sugar in each bread solution.
Equipment requirement:
test tube x5
180 gram of sugar
water bath x1
150 gram of all purpose flour
350 ml of water
weight scale
Yeast
Type of microbials
Yeast
Metabolism of yeast
Respiration
Aerobic
Glucose + O2 => CO2 + ATP + Water
Anaerobic
Glucose => Lactic Acid
Fermentation
Glucose => CO2 + Ethanol
Bacteria
Fungi
Mold
Methods of measuring the rate of growth
using a measuring cylinder, measuring the initial volume of the bread dough, and after a certain amount of time, record the final volume.
Food production by microbials
Fermentation
Bread making
Beer making
improve tastes
Conditions:
Water
Atmosphere/ Oxygen and Carbondioxide
Nutritions
Temperature
Factors affecting the growth of microbials:
Intrinsic factors:
Water availability
The foods with high water contain or moist are the ideally growing condition for microbes.
pH
Generally, most microbes prefer neutral pH.
Nutrients
In a nutrition rich environment, microbes growth faster.
Biological barriers
This is an outer cover which protect food from the invasion of microbes.
Antimicrobial chemicals
This is a type of chemical that inhibits the growth of microbes to prevent spoilage.
Extrinsic factors:
Atmosphere
Microbes develop best in the Oxygen rich condition.
Temperature
Microbes multiply best in the warm condition.
Hypothesis :
The higher amount of sugar in the bread solution, the greater rate of growth of the yeast.
Methods
Mix yeast with sugar, warm water( warm water temperature should be similar for all trials) and bread dough as well.
Place the bread solution into a 100 ml beaker (measure the weight of each bread solution and make sure that they are similar to make a fair test).
Cover the beaker with plastic wrap for 30 minutes before measuring the growth. (Covering the beaker will prevent water loss, maintaining the moisture to support the growth of yeast).