Professor Nwokocha's Part Flashcards
What is Homogenous catalysis?
Homogenous catalysis is a type of catalysis in which the reactants and thecatalysts are in the same phase, this allows a uniform distribution of molecules making the reaction very fast.
Examples of homogenous catalysis
*esterification of alkanol and alkanoic acid in the pressure of H2SO4
*Hydration of ethene to form ethanol using H2SO4
*Dehydration of ethenol to form ethene H2SO4
In what phase does homogenous catalysis occur in the most
Liquid phase
What’s Heterogeneous catalysis?
Reactants and catalyst are in different phases
Examples of Heterogeneous catalysis
*Haber process using Iron fillings
*Contact process using V205
*Hydrogenation of oil to give fat.
Examples photocatalysis
This type of catalysis is initiated by light which initiates the initiators which give free radicals
Eg substitution reaction of methane in the presence of light.
What’s an advantage of Homogenous catalysis?
Not limited by positions, therefore proceed to react at a very fast rate
What’s fermentation?
Fermentation is a biochemical process in which simple fermentable carbohydrates are converted to alcohols and CO2 or organic acids in the presence of fermentable enzymes from yeasts and bacteria under anaerobic conditions.
Who discovered fermentation?
Louis Pasteur
Who concluded that enzymes in microbes were responsible for fermentation?
Buchner
Define Zymology
Science of fermentation
What’s the importance of fermentation?
*Hint IPDND
*Improves the taste of rather bland food
*Preserve food from degradation by noxious organisms
*Improves the digestibility of food that are not easily assimilated
*Improves the nutrients of food
*Prevents the detoxification of food.
Fermentable foods examples
Sweet sorghum, beetroot, sugarcane, cheese, maize, rice, barley, fruits etc
What’s the purpose of hops, barley and water in beer production?
Hops are used for preservation purposes and also for improving taste
Barley is used to provide the fermentable sugar which is fermented to form beer
Water - to initiate germination and to increase volume
Why is Barley used?
*it’s cheap
*Contains necessary enzymes to break down and hydrolyze to form fermentable sugars.
*It’s consistent in taste
What’s Beer Purity Act?
Formed in 1516 and restricts brewery of beer to the 3 ingredients
Why is yeast added in brewery of beer?
In order to facilitate the conversion of fermentable sugars to alcohols and CO2
What does Malting stage entails?
*steeping
*Germination
*Kilning
What happens in the steeping process?
*water moisture is increased from 12 to 43-46 percent
*The enzymes in the barley required for saccharification are activate ie glucanase and amylase.
*Occurs for 2-3days
*Done through immersion and dry standing
Germination process?
*the glucanase in the barley becomes activated and breaks down the endosperm, cell wall materials of the plaht
*Amylase converts the cellulose/starch into fermentable sugars
*There’s formation of fermentable sugars
Unhydrolyzed sugars are unwanted before of filter clogging and unwanted viscousity.
Kilning?
This involves exposure of germinating barley to hot air in order to cause denaturation in enzymes responsible for saccharification. This prevents usage of fermentable sugars for plant growth.
Calberg Brewery at Copenhagen have deviced ways to express glucanase enzymes of thermophilic bacteria to the barley. This allows for continuous saccharification even when the further germination of plants has been arrested.
What is malt?
Dried germination grains
Explain how thermophilic glucanase improve livestock growth?
Feeding livestock with GM barley is good for the growth because it provides glucanase which helps livestock to break down endosperm of feed given to them.
Explain fermentation process of beer making
Fermentable sugars from the Malting process are now converted into alcohol with the effervescence of CO2 or the formation of organic acid by the action of enzymes present in microbes like yeast and bacteria under anaerobic conditions.
