2. recall: biotechnology
•ancient
•early history as related to food and
shelter, including domestication
!
•traditional (classical)
•built on ancient biotechnology
•fermentation promoted food
production and medicine
!
•modern
•manipulates genetic information in
organism
•genetic engineering
mitalee.wordpress.com
3. Grabbed from the PPT lectures of
Professor/Dr. Arnold V. Hallare,
(2013)
4. what to learn today…
•overview of metabolism:
aerobic and anaerobic
respiration
•Fermentation in Plants
•Fermentation in
Animals
•Fermentation in
Humans
•traditional
biotechnology:
fermentation
•virtual lab
blog.leonardo.com
6. cellular respiration: a catabolic reaction
•process of making ATP by breaking down
organic compounds
•exergonic
•oxygen (O2) requiring
•uses energy extracted from
macromolecules (glucose) to produce
energy (ATP) and water (H2O)
enzymes
6O2 + C6H12O6 6CO2 + 6H2O
oxygen glucose carbon dioxide water
ADP + Pi
ENERGY transfer
between enzymes,
other molecules ATP
7. stages of aerobic respiration
• glycolysis:
cytosol
• krebs cycle:
mitochondrial
matrix
• ETC: inner
mitochondrial
membrane
You may watch a video here about GLYCOLYSIS: http://
www.science.smith.edu/departments/Biology/Bio231/
11. anaerobic respiration in plants
www.ipm.iastate.edu In response to flooding stress
www.vce.bioninja.com.au
12. anaerobic respiration in animals
www.fashioncentral.pk
www.vce.bioninja.com.au
slow twitch versus fast twitch
muscles
13. slow twitch and aerobic respiration
• example: dark leg meat of
chicken
• Specialised for slow, sustained
contractions over a long period
for endurance
• contain lots of myoglobin which
acts as a store of oxygen
• Respire aerobically
14. slow twitch works best in:
or if you wanna try duathlon
when you try running the bdm ultramarathon
(160km)
15. lactic acid in meat?
• fast twitch
• example: pectoral flight muscles
(chicken breast)
• for producing rapid, intense
contractions of short duration for
rapid movement
• do not have myoglobin so Respire
anaerobically
• can accumulate lactic acid and
leads to fatigue
thoughtchalk.com
16. fast twitch works best in:
Provide the muscle power for rapid, fast
movement e.g. a cheetah's burst of speed to
catch a gazelle, or the gazelles burst of
speed to escape the cheetah
or to power up usain bolt’s
legs in sprints
omarmcknight.com
18. fermentation in humans
•farting
•When carbon dioxide is
used as an electron
acceptor, the product is
either methane or acetic
acid
•Methane produced in our
gut is produced by this
process
www.ausforces.com
20. fermentation : classical biotechnology
•the use of microbes
to enhance food
flavor
•the use of microbes
to manufacture of
beverages
•the use of microbes
to make the dough
rise
21. products of fermentation: beer
•An alcoholic beverage produced by the fermentation
of sugar-rich extracts derived from cereal grains or
other starchy materials
•ancient biotechnology: beer brewing
•Sumaria (4000 BC)
•Sikaru
•Egypt (3000 BC)
•Zythum
•India (2000 BC)
•Sura
•China (2000 BC)
•Kiu
www.nomad4ever.com
22. yeast in beer brewing
•1680 Antonie van
Leeuwenhoek Observed yeast
in beer
•1837 - Cagniard Latour
decsribed that Microbe is
responsible for alcoholic
fermentation
•1866 - Louis Pasteur stated
that Yeast was responsible
for alcoholic fermentation
•1883 - Emil Christian Hansen
Developed pure culture
technique and Isolated pure
cultures of brewing yeasts
Weiss Ale
Lager Lab
Kindly provided by Tom Pugh and David Ryder of Miller Brewing Company
Kindly provided by Tom Pugh and David Ryder of Miller Brewing Company
23. microbes and beer brewing
•malted barley
Provides fermentable
sugars, flavor, and
color
•hops Provides aroma
and bitterness
The Brewing Process
Step Purpose
Brewhouse
Fermentation
Lagering
Starch Sugars
Wort production
Sugars Ethanol
Flavor production
Carbonation
Flavor maturation
Kindly provided by Tom Pugh and David Ryder of Miller Brewing Company
The Brewing Process
Malt Mill
Mash Tun Cereal
Cooker
Lauter Tun
Brew
Kettle
Hot Wort
Receiver
Wort
Cooler
Brink Fermentation
Aeration
Lagering
Hops
Kindly provided by Tom Pugh and David Ryder of Miller Brewing Company
24. microbes and beer brewing
Yeast Metabolism During Fermentation
Sugars Oxygen
Glucose
Pyruvate
TCA
Cycle
Amino Acids
Energy
CO2
Ethanol
Acetaldehyde
Organic Acids
Unsaturated Fatty Acids
Sterols
Amino Acids
Esters
Higher
Alcohols
VDK
Sulfur
Volatiles
Membranes
Kindly provided by Tom Pugh and David Ryder of Miller Brewing Company
25. products of fermentation: cheese
•cheese are ripened curds
•milk is treated with lactic acid bacteria
and rennin to coagulate proteins
•curds + whey = milk
•different microbes
in the early and
late stages of
processing of
cheese = different
cheese
characteristics
idiva.com
26. types oTfy pcesh oef Cehseeese
Acid Coagulated Fresh Cheese (lactic acid from
bacteria)
• no enzyme is used to finish the curd
• Cottage and Cream Cheese
Heat-Acid Precipitated Cheese (acid and heat
precipitate/coagulate the protein and cause milk fat
to curdle)
• Add low amounts of acid to 75-100oC temp milk
• High moisture and protein
• Ricotta (Italy) Channa and Paneer (India)
science of cooking
27. types oTfy pcesh oef Cehseeese
Semi-hard Washed Cheese (washing cheese
removes acid and lactose)
• Acid and enzyme induced curdling
• But removal of milk sugar and acid results in no
fermentation results in a moist and less finished cheese
• Gouda, colby, muenster, mozzarella …
Hard Cheese (Low and High Temp)
• Low moister makes a more dense hard cheese
• Elevated temps and pressing drive off water
• Cheddar, Romano, Parmesan, Swiss,
science of cooking
28. swiss cheese and propionibacterium
science of cooking
Finishing Microbes
Holy Cheese (cow)? – Propionibacteria:
• Convert lactic acid to propionoic and acetic acid plus acetic
acid and CO2. Also other flavors
• Used to make Swiss Cheese
• Need higher temps and time for bacteria to grow and produce
• Growth requirements reflect
origins of bacteria
animal skin
Lactic acid
Propionoic acid
+
Acetic acid Carbon Dioxide (g)
Finishing up…
29. Blue Cheeses – Based on Origen
fungi and blue cheese
Roquefort - France Cambreles- Spain
Stilton- England
Danish Blue Cheese
Gorgonzola- Italy
science of cooking
Penicillium roqueforti and P. camberti
BLUE = MYCELIA/ or growth filaments
30. making the cheese
Non Starter–
ripening
Starter – acid
producing
0 50 100 150 200
science of cooking
Bacteria Growth
Time (Days)
31. product of biotechnology: breads
•biotechnology’s first utilization of
microbes = bread making
•Around 4000 BC, Egyptians used the
living organism yeast to make bread
•Airborne wild yeast accidentally got
their bread dough, causing it to rise
www.acebakery.com
32. the sourdough bread
•microbe one (AEROBIC): yeast
•makes carbon dioxide and bread will rise
•microbe two: anaerobic: lactic acid
bacteria
•make lactic acid and acetic acid that give
rich complexity of flavors
www.weekendbakery.com foodists.ca www.rootsimple.com
33. products of fermentation: wine
•after bread comes wine: 3000 bc
•converts sugars in grapes into alcohol
www.cell.com
34. making your wine
http://www.chinookwines.com
1. harvest
2. processing
3. fermentation
35. making your wine
http://www.chinookwines.com
4. maturation
6. bottling & corking
5. fining and filtration
36. products of fermentation: yoghurt
•FERMENTED MILK
RESULTING TO A SEMI-SOLID
CURD
•LACTIC ACID BACTERIA =
PROBIOTICS
•AIDS IN DIGESTION
•ACID PRODUCED DURING
FERMENTATION CAUSES
THE PROTEIN TO
COAGULATE
•Lactococcus lactis,
Streptococcus
thermophilus and
Lactobacillus bulgaricus
www.wombourneshopping.co.uk
37. how to make yoghurt
Making Yogurt in 4 Simple Steps
1. Start with Cow, Sheep, or Goat milk.
2. Heat milk to 80 °C. Two purposes:
• destroy existing bacteria
• condition the proteins = begins the denaturing process
(a whey protein molecule binds to a casein molecule which disrupts
the casein bundles allowing them to make short branched micelle
chains)
3. Cool milk to 40 °C and innoculate with bacteria
4. Incubate at 30 °C to 45 °C
Casein before heat
pre-treatment:
Casein after heat
pre-treatment: Casein after acid:
www.bnc.asn.au
38. bacteria in yoghurt
Milk Yogurt
Casein protein micelles Bacteria produce acid
(bundles)
10-7 meters in diameter
Fat
globule
Acid causes
Casein bundles to
fall apart into
separate casein
molecules.
These rebind to
each other in a
network that traps
water.
= makes a gel
