Micro 3050 Exam 4 Clemson
What general microorganism is responsible for fermenting sugar into alcohol? - Correct
Answer-- Yeasts
What is the alcohol content of wine? How is wine made? - Correct Answer-- 10 - 14%
- Crush grapes → Must, add sulfur dioxide fumigant to kill wild yeast (they lower alcohol
content)
- Add yeast (saccharomyces)
- Ferment for a few days at room temp
- MAY do secondary fermentation, add LAB to make it taste buttery via lactic acid
- Aging adds flavor, racking/turning gets sediments removed, and fining clarifies it
Explain the difference between red and white wine? Sweet and dry wine? - Correct
Answer-- Red = pulp is fermented with it, ages longer
- White = puls is removed before fermentation
- Sweet = super sugary grapes, and not all the sugar was fermented
- Dry = less sugary grapes, and all of the sugar was fermented
Describe lactic acid bacteria and their role in fermented foods. - Correct Answer-- Gram
positives, acid TOLERANT, non-spore forming, commonly found in milk
- Typically ferment milk to make dairy products
- Heterolactic vs Homolactic
Define probiotics and prebiotics - Correct Answer-- Probiotic: LIVE microorganisms
given in adequate amounts to benefit the health of the host
- Prebiotic: Substances that help probiotics grow
- Ex. Could be food you eat that protects them from stomach acid, thing that help them
stay longer
List some pros of probiotics? - Correct Answer-- Often beneficial for healthy people
, - Improve intestinal health/microflora (ex. colonization resistance)
- Some LAB associated with anti-cancer compounds
- Bind with LDL cholesterol, lower BP
- Improve oral health
- Immunomodulation
List some cons of probiotics? - Correct Answer-- Don't work the same for everyone
- Not FDA regulated, misleading advertisements
- Side effects can happen from trying to change gut microflora, and the
immunocompromised may encounter opportunistic pathogens
What is the alcohol content of beer? How is beer made? - Correct Answer-- 4 - 6%
- Malt the grains (germinate) to get sugars out and crush it to make mash
- Boil mash with hops for flavor, filter out the hops so you're left with wort
- Inoculate wort with yeast and ferment it
What is the difference between ale and lager? - Correct Answer-- Ale = top yeasts,
ferment for shorter time at warm temperature
- Lager = bottom yeasts, stored for longer time at cold temperature
What is the alcohol content of distilled spirits? How are they made? What about
whiskey/bourbon specifically? - Correct Answer-- +60%
- Take any fermented solution and distill it (tubing collects vapor and condense it to
concentrated alcohol)
- Whisky/bourbon: inoculate mash with HOMOLACTIC bacteria to sour it, distill it to
concentrate it (stored in oak barrels to give it color)
How is drinking water treated? What is special about chlorine? - Correct Answer--
Remove large sediments from raw water
- Add coagulant to precipitate them out
What general microorganism is responsible for fermenting sugar into alcohol? - Correct
Answer-- Yeasts
What is the alcohol content of wine? How is wine made? - Correct Answer-- 10 - 14%
- Crush grapes → Must, add sulfur dioxide fumigant to kill wild yeast (they lower alcohol
content)
- Add yeast (saccharomyces)
- Ferment for a few days at room temp
- MAY do secondary fermentation, add LAB to make it taste buttery via lactic acid
- Aging adds flavor, racking/turning gets sediments removed, and fining clarifies it
Explain the difference between red and white wine? Sweet and dry wine? - Correct
Answer-- Red = pulp is fermented with it, ages longer
- White = puls is removed before fermentation
- Sweet = super sugary grapes, and not all the sugar was fermented
- Dry = less sugary grapes, and all of the sugar was fermented
Describe lactic acid bacteria and their role in fermented foods. - Correct Answer-- Gram
positives, acid TOLERANT, non-spore forming, commonly found in milk
- Typically ferment milk to make dairy products
- Heterolactic vs Homolactic
Define probiotics and prebiotics - Correct Answer-- Probiotic: LIVE microorganisms
given in adequate amounts to benefit the health of the host
- Prebiotic: Substances that help probiotics grow
- Ex. Could be food you eat that protects them from stomach acid, thing that help them
stay longer
List some pros of probiotics? - Correct Answer-- Often beneficial for healthy people
, - Improve intestinal health/microflora (ex. colonization resistance)
- Some LAB associated with anti-cancer compounds
- Bind with LDL cholesterol, lower BP
- Improve oral health
- Immunomodulation
List some cons of probiotics? - Correct Answer-- Don't work the same for everyone
- Not FDA regulated, misleading advertisements
- Side effects can happen from trying to change gut microflora, and the
immunocompromised may encounter opportunistic pathogens
What is the alcohol content of beer? How is beer made? - Correct Answer-- 4 - 6%
- Malt the grains (germinate) to get sugars out and crush it to make mash
- Boil mash with hops for flavor, filter out the hops so you're left with wort
- Inoculate wort with yeast and ferment it
What is the difference between ale and lager? - Correct Answer-- Ale = top yeasts,
ferment for shorter time at warm temperature
- Lager = bottom yeasts, stored for longer time at cold temperature
What is the alcohol content of distilled spirits? How are they made? What about
whiskey/bourbon specifically? - Correct Answer-- +60%
- Take any fermented solution and distill it (tubing collects vapor and condense it to
concentrated alcohol)
- Whisky/bourbon: inoculate mash with HOMOLACTIC bacteria to sour it, distill it to
concentrate it (stored in oak barrels to give it color)
How is drinking water treated? What is special about chlorine? - Correct Answer--
Remove large sediments from raw water
- Add coagulant to precipitate them out
