2. Scientific Evaluation: Being Objective
Chapter 2
Scientific Evaluation: Being Objective

3. Objectives
Describe the role of science in the development of new food products.
Identify the function of measuring equipment used in the science laboratory.
Demonstrate proper measurement techniques.
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4. Objectives List the steps of the scientific method.
Use proper safety procedures in the food science lab.

5. Science in the Food Industry
Science is the systematic knowledge of natural and physical phenomena
A phenomenon is a fact, occurrence, circumstance, or process that is observed
Scientific study in any field requires
unbiased observation
accurate measurement
organized documenting of results
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6. Science in the Food Industry
Food science is an applied science
Knowledge gained by scientists is put to practical use
An experiment allows scientists and researchers to apply basic laws of science and nutrition to the production, processing, and packaging of the food supply
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7. Science in the Food Industry
The recipes developed through controlled experiments are called formulations
To be scientific, they must be replicable, or repeatable
©zebrik/Shutterstock

8. Measurements Successful measuring requires you to
identify what measurement standard is being used (International System of Units, for example)
determine what you are trying to measure
decide what method of measurement will give the most consistent results
specify the unit of measure used

9. Measuring Mass Mass measures the quantity of matter
The metric unit for measuring mass is a gram (g)
It is the mass of 1 cubic centimeter of water at 4°C
A kilogram (kg) is the mass of 1 liter of water at 4°C
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10. Measuring Mass
Weight is the measure of the force of gravity between 2 objects
The triple beam balance and the electronic balance are used to measure mass
When turning on an electronic balance, you need to calibrate it
Liquids will need to be placed in a container before massing them

11. Measuring Length Length is the distance between 2 points
The metric unit for measuring length is a meter (m)
One meter is equal to inches
Length is usually measured with a ruler
To obtain a more accurate measure, identify the end points of the object

12. Measuring Volume Volume is the amount of space occupied by an object
The metric unit for measuring fluid volume is the liter (L)
One liter equals the amount of space 10 cm high by 10 cm wide by 10 cm deep
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13. Measuring Volume Equipment used to measure liquids
beaker—a wide mouthed container with a pouring lip
Erlenmeyer flask—a cone-shaped container with a flat bottom
graduated cylinder—a tall, thin container with a pouring lip
buret—a graduated glass tube

14. How to Measure Volume Place container on a flat surface
Take readings at eye level
In narrow containers read from the bottom of the curve at the liquid’s surface, the meniscus
©Goodheart-Willcox Publisher

15. Measuring Time
Time is measured in seconds in most food science experiments
In an experiment, appoint someone to act as a timer to record start and stop times with a clock or watch
Failure to monitor time precisely can make the experiment invalid

16. Measuring Temperature
Temperature is a measure of heat intensity
Celsius degree is 0.01 of the difference between the boiling and freezing points of water
Water boils at 100°C
Water freezes at 0°C

17. The Scientific Method
The scientific method is a system of steps used to solve problems
Ask questions
Ask what, why, and how of a problem
Define the problem
Clarify the question
Set specific goals
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18. The Scientific Method Conduct research
List possible causes of the problem
Gather as much information as possible
State the hypothesis, or possible solution
A hypothesis repeatedly tested over a variety of conditions becomes a theory
Laws are theories widely accepted as explaining and predicting phenomena
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19. The Scientific Method Design the experiment
Make it answer questions such as how to test the hypothesis, what equipment will be used, how to collect and record the data, and what safety precautions need to be taken
A well-designed experiment will have a variable and a control
Each change in an experiment is a variation
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20. The Scientific Method Conduct the experiment
Follow procedures exactly and measure accurately
Records of observations will be numerical or descriptive
Record data appropriately and neatly
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21. The Scientific Method Evaluate the results
Reflect on what you know combined with what you have observed
Look for patterns, common factors, changes, and questions
Look for answers to the questions and whether they provide support for or against the hypothesis
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22. The Scientific Method Report the results
A conclusion analyzes and applies data rather than just repeat it
Experiments may lead to more than one conclusion and reveal the need for further research
Scientists report results in a variety of ways and describe how the results may be applied

23. Evaluating Scientific Studies
Scientific research is a process of discovery and debate
Medical experts may be involved to evaluate scientific evidence
This took place during the 2010 update of the Dietary Guidelines for Americans, which recommend consuming more nutrient-dense foods
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24. Evaluating Scientific Studies
Conflicting reports may exist
Researchers often examine hundreds of studies before making recommendations to the public
A meta-analysis gives overall conclusions to multiple studies of the same issue

25. Lab Safety General guidelines
Follow lab rules and experiment procedures
Avoid horseplay
Keep hair under control
©USDA
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26. Lab Safety General guidelines Be cautious around heated glass
Remember hot glassware looks the same as cold glassware
Protect eyes, skin, and clothing when working with strong acids and bases
Mix chemicals only as instructed
Dispose of chemicals properly
Plan time for lab cleanup

27. Recap
Food scientists develop new food products and better methods of preserving and preparing food through experimentation
Using proper measuring equipment and techniques are crucial during food science experiments
Avoid accidents by following all lab safety procedures at all times
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28. Recap The steps of the scientific method are to ask questions
define the problem
conduct research
state the hypothesis
design the experiment
conduct the experiment
evaluate the results
report the results