UF FOS3042 Exam 1 questions and
answers
Maillard Reaction ✔✔A type of non-enzymatic browning reaction that is
different from the enzymatic browning of apples by polyphenol oxidase
(PPO) or the caramelization of food
Non-enzymatic browning ✔✔Maillard browning (i.e. browning of bread
crust), Addition, and Hydration
Enzymatic browning ✔✔Polyphenol oxidase browning (i.e. browning of
apple flesh)
Enzymatic and Non-enzymatic browning ✔✔Condensation, Hydrolysis, and
Oxidation-Reduction
Water activity (Wa): concept ✔✔A concept that describes the availability of
free water in food (which impacts microbial growth), and it ranges from 0 to
1
Water activity (Wa): definition ✔✔The ratio of the water vapor pressure of
the substance to the water vapor pressure of pure water
pH of acidic foods: low ✔✔pH above 4.6
, pH of acidic foods: high ✔✔pH below 4.6
Organic acids that are common in food ✔✔Citric acid, malic acid, tartaric
acid, lactic acid, fumaric acid, and acetic acid
Titratable acidity ✔✔Estimates the total acidity of the solution and is
measure by titration of the acids in the food system with a standard base
Titratable acidity: what is it based on? ✔✔Measure is based on the amount
of both associated and dissociated ions. It is NOT the same thing as pH
pH ✔✔The measure of the strength and concentration of only the
dissociate ions present in the medium
Citric acid ✔✔Most common acid added to food
Microbe growth: water activity level ✔✔Typically cannot grow at a water
activity level of 0.6 or lower
Emulsion: oil-in-water ✔✔Water is the predominant part
Emulsion: water-in-oil ✔✔Oil is the predominant part
answers
Maillard Reaction ✔✔A type of non-enzymatic browning reaction that is
different from the enzymatic browning of apples by polyphenol oxidase
(PPO) or the caramelization of food
Non-enzymatic browning ✔✔Maillard browning (i.e. browning of bread
crust), Addition, and Hydration
Enzymatic browning ✔✔Polyphenol oxidase browning (i.e. browning of
apple flesh)
Enzymatic and Non-enzymatic browning ✔✔Condensation, Hydrolysis, and
Oxidation-Reduction
Water activity (Wa): concept ✔✔A concept that describes the availability of
free water in food (which impacts microbial growth), and it ranges from 0 to
1
Water activity (Wa): definition ✔✔The ratio of the water vapor pressure of
the substance to the water vapor pressure of pure water
pH of acidic foods: low ✔✔pH above 4.6
, pH of acidic foods: high ✔✔pH below 4.6
Organic acids that are common in food ✔✔Citric acid, malic acid, tartaric
acid, lactic acid, fumaric acid, and acetic acid
Titratable acidity ✔✔Estimates the total acidity of the solution and is
measure by titration of the acids in the food system with a standard base
Titratable acidity: what is it based on? ✔✔Measure is based on the amount
of both associated and dissociated ions. It is NOT the same thing as pH
pH ✔✔The measure of the strength and concentration of only the
dissociate ions present in the medium
Citric acid ✔✔Most common acid added to food
Microbe growth: water activity level ✔✔Typically cannot grow at a water
activity level of 0.6 or lower
Emulsion: oil-in-water ✔✔Water is the predominant part
Emulsion: water-in-oil ✔✔Oil is the predominant part
