Food Science 1
Unit 3
Scientific Evaluation: Being Objective
 Science: ________________________________________________________________.
 Phenomenon: ___________________________________________________________.
Scientists watch what happens under controlled conditions, to determine why things
happen as they do.
From _____________ and _____________________ scientists can discover the
predictable behavior patterns of the natural world.
For success in the food science laboratory basic guidelines should be followed. Avoid
biases, base conclusions on what truly happens,
________________________________________ , observe carefully, keep detailed
records, etc.
Scientific Method:
Food Science in Industry
 Applied science:
__________________________________________________________.
 Experiment: a controlled situation that allows a scientist or researcher to
_________________. _____________________________________________(ex. the
best way to prepare something)
 Formulations: _________________________________________________.
 Replicable: ________________________________
 Scientific Method:
Measurements
 To take accurate measurements:
◦ Identify what system of measurement or standard you are using.
◦ Determine what you are trying to measure
◦ Decide what method of measurement will give you the most
_____________________.
To help scientists all over the world share information an international system has been
developed based on ___________________________________________ –
International System of Units (SI)
Units measure ___________________________________________________________.
Measurements - Mass
 Mass: __________________________________________________________________
Gram (g)= __________________________________________________________________
Kilogram (kg) =the mass of l liter of water at 4 degrees C (39 degrees F) One kg = 1000 g.
Weight = __________________________________________________________________.
May change with location
For accuracy scientists need measurement that _______________________ from place
to place.
Massing compares the substance to a standard mass.
 Triple beam balance – works on same principle as a seesaw- ______________________
– gravity the same no matter where location.
 Electronic balance – faster, easier to use
◦ Calibrate - ________________________________________________________.
◦ To calibrate electronic balance, must measure a standard mass first, the balance
will then compare all substances measured to that mass.
Measurements – Length
 Length: _______________________________________________________________
 Meter: the standard____________ of _____________________ in the metric system.
◦ One meter = 39.27 inches
◦ You will usually record length measurements in __________and______________
◦ One micrometer = 0.000001 meter.
Measurements – Volume
 Volume: ______________________________________________________________.
Volume is a measurement derived from length.
 Liter: _________________________________________________________________.
 Beaker: a deep, wide-mouthed container with a pouring lip used to hold substances
during experiments.
 Erlenmeyer flask: ________________________________________________________.
 Graduated cylinder: tall container used to accurately measure the _________________
_________________ to the nearest milliliter.
 Buret: graduated glass tube with a control valve at the bottom, used to pour an
accurate amount of liquid.
 Meniscus: ______________________________________________________________.
 How to measure volume:
 Place container on a level surface
• Holding at an angle alters the reading
 Read volume at eye level
• Viewing at an angle will make the liquid look larger than it really is
 Time – in most food science experiments time will be measured in seconds.
• Record start and stop times _________________________.
• Failure to monitor time accurately can invalidate the experiment.
 Temperature: _____________________________________________.
• Celsius temperature scale – based on boiling and freezing points of water.
 Water freezes ____________________.
 Boils at 100 degrees C
• Celsius degree – 0.01 of the difference between boiling and freezing.
• ___________________– most commonly used in the U.S.
 Most lab thermometers marked with both ________________________.
 Always specify units being measured.
 _______________________________
Scientific Method: system of steps used to solve problems.
 Step 1 - Forming a hypothesis
Possible explanations for questions and problems




Definition: __________________________________________ – an educated guess.
•What am I trying to prove?
•What questions do I want to answer?
To form a hypothesis, you use inductive and deductive reasoning skills.
•______________ – drawing a general conclusion from specific facts or
experiences
•______________ – works in the opposite direction. You reach a conclusion
about a specific case based on known facts and general principles.
* “if/then” statements
* the known fact (“if”) leads to a logical conclusion (“then”)
Repeat the experiment to see whether results are consistent. If the results are
consistent, you may draw valid conclusions from them.
Step 2 – Experimentation
 The heart of the scientific method.
 Definition: a way to test a hypothesis in order to verify or disprove it.
 • Identify and create the conditions that put their hypothesis to
the test.
 • Includes :
 * List of equipment
 *Materials
 *Procedure that gives step-by-step instructions and how
to use these items and record results
 Controlling variables
 Definition of variables: __________________________________.
 By controlling all the variables except one, you get more reliable
results
 Independent variable – ________________________.
 Dependent variable – a factor that changes as a result of
the independent variable
Step 3 - Analyzing Data
• Data – ________________________________________________.
• The Data Table – scientists arrange data in a clear and logical form.
• Repeat the experiment to see whether results are consistent. If the results are
consistent, you may draw valid conclusions from them.
Step 5 – Reporting the Results
• ______________________ – to learn as much as possible form an experiment,
you need an organized format for reporting laboratory results.
Step 4 – Developing and revising theories
• “No amount of experimentation can ever prove me right; a single experiment
can prove me wrong.” – Albert Einstein
• Good science is a
________________________________________________________.
• A hypothesis that is consistently verified may be established as a theory.
•
Definition of theory: an explanation ________________________________
from many observations and supported by the results of many experiments.
• A hypothesis is a possibility; a theory is a probability.
• A theory may be refined, broadened or disproved as new discoveries are made.
 Step 6 – Conducting Research
• Investigating _____________________________________________________.
• Research and experimentation complement each other.
 Choose a topic that interest you and let your observations spark your
curiosity.
 Narrowing the focus
 Finding Information
Evaluating Scientific Studies
 Meta-analysis: __________________________________________________________
conclusions.
 When assessing new research, ask the following:
• Can the study be ______________________ in another way?
• Are there any flaws or biases in the method or way the study was conducted?
• How does this study fit in with the current body of research on the subject?
• What are the ___________________of this study?
 Remember that the scientific process requires ongoing discussion and debate.