🔬 Scientific Method
What is the main purpose of the scientific method?
To investigate questions using evidence and experiments.
What is cross-contamination?
The transfer of harmful contaminants between foods, utensils, or surfaces.
Which food preservation method removes moisture from food?
Dehydration or drying.
Why do we add salt to the ice surrounding our homemade ice cream mixture?
To lower the freezing point of the ice-water mixture so it becomes cold enough to freeze the ice cream.
What is marbling in beef?
Small flecks or streaks of fat within the muscle.
In an experiment, what is the independent variable?
The factor the scientist intentionally changes.
What temperature range is commonly called the food safety danger zone?
40°F to 140°F.
How does refrigeration help preserve food?
It slows microbial growth and chemical reactions.
What causes a cut apple to turn brown?
Enzymatic oxidation involving oxygen.
Which USDA beef quality grade generally has the greatest marbling: Prime, Choice, or Select?
Prime
Why should an experiment include a control group?
To provide a baseline for comparing the results of the treatment groups.
What is the safest way to determine whether chicken has reached a safe cooking temperature?
Use a food thermometer to check its internal temperature; poultry should reach 165°F.
Why does vacuum-sealed raw meat still need refrigeration or freezing?
Removing air does not kill all microorganisms, and some harmful microbes can grow without oxygen
How does shaking the bag during our ice cream lab affect the finished ice cream?
It helps form smaller ice crystals and produces a smoother texture.
What is the difference between USDA meat inspection and beef quality grading?
Inspection focuses on safety and wholesomeness; quality grading evaluates characteristics associated with eating quality.
What is a confounding variable?
An unintended factor that changes the results of an experiment.
Why might a food company recall a product that contains undeclared peanuts?
Because peanuts are a major allergen and could cause a serious allergic reaction.
How does canning help preserve food?
It uses an appropriate heat-processing method and sealed packaging to control microorganisms and prevent recontamination.
What is homogenization in dairy processing?
Breaking fat droplets into smaller sizes so the mixture stays more uniform.
What does grass-finished beef mean?
Beef from cattle finished on grass or other forage rather than a grain-based finishing diet.
Why do scientists repeat experiments and use multiple samples?
To check consistency and reduce the influence of unusual results.
What is the difference between a biological food hazard and a physical food hazard? Give an example of each.
Biological: a harmful microorganism, such as Salmonella. Physical: a foreign object, such as glass.
What is polyphenol oxidase, and what role does it play in apple browning?
It is an enzyme that helps cause oxidation reactions that turn cut apples brown.
Why does sugar influence the freezing and texture of ice cream?
Sugar lowers the freezing point and helps influence softness and ice crystal formation.
Why can't you determine whether raw meat is safe to eat based only on its color?
Harmful microorganisms may be present without causing visible color changes.