Yeast Fermentation Rates

IB Biology Internal Assessment Yeast Fermentation order Planning(a) Question- Growth What is the progenyuate on Yeast Growth/Expansion during excitement when mixed in water of varying temperatures? Hypothesis- Temperatures above or beneath the recommended fermentation temperatures depart contain less, or be void of growth, each due to inactivation or to yeast death. Variables- Dependent Variables TempDegrees F 90 Degrees F- one hundred thirty Degrees F erat ure of wate r. Fermentation Hours Level of Digital Timer condemnation expansion later other variables 90 75mL 75mL 75mL N/A N/A 100 105mL 75mL N/A N/A N/A 110 85mL 75mL 75mL N/A N/A long hundred 125mL 75mL N/A N/A N/A 130 75mL 75mL N/A N/A N/A data Processing and Presentation- Overview- Yeast is a living substance. It is commonly used to hold up bread, or to make alcohol, in a process known as Alcoholic Fermentation in which it releases oxygen. Through my resea rch, I learned that during fermentation, the temperature is a very important factor in yeast expansion, as on a lower floor 100 degrees, the yeast may not activate, while high temperatures will effectively kill your yeast, rendering it useless. My Lab Experiment served to test the effect of temperature on yeast expansion during fermentation. Presentation- Temperature Repeat Volume Change 90 1 0mL 2 0mL 3 0mL 4 N/A 5 N/A 100 1 30mL 2 0mL 3 N/A 4 N/A 5 N/A 110 1 10mL 2 0mL 3 N/A 4 N/A 5 N/A 120 1 50mL 2 0mL 3 N/A 4 N/A 5 N/A 130 1 0mL 2 0mL 3 N/A 4 N/A 5 N/A Yeast Expansion Conclusion and Evaluation- Conclusion- As is shown by my data, after the starting signal trial at each temperature, the yeast refused to rise. This is due to temperatures effect on yeast, as a living thing. After completing the first five trials and ending my experiment for the day, I pl aced the jar of expeditious dry yeast in the fridge where, due to prolonged characterisation to such low temperatures, the whole jar died.After frustratingly watching the near seven trials yield no rise in the yeast, I came to the actualisation that the cold of the fridge killed my yeast. This was just as much a move (as the jar said refrigerate after opening), as it was an interest basis for my lab. Because my Lab was about Temperatures effect on yeast expansion and growth, this death provides a good conclusion, as it shows that prolonged exposure to extreme cold(around 58 Degrees F in my fridge), effectively kills the yeast, just as exposure to extreme heat does. At the 90 Degrees of trial 1, the yeast simply was not activated, but at 130 degrees, it also didnt activate.Because temperatures below 130(save 90) activated it, I assumed that this was the temperature that kills yeast, just as 58 Degrees does. Limitations of experimental design- Many aspects of my project did not work very wellspring and could seduce been improved in order to make for a ruin experimental design. For instance, instead of simply placing the yeast in water, I could have made dough, and placed it in the oven at different temperatures, making for a much more stable environment and temperature. Also, completing all 25 trials would have yielded better results as to what temperature truly leads to the greatest expansion by the yeast during fermentation. pic