Pre-distillation and Fermentation Flashcards
(101 cards)
1
Q
What is the term used for the fermented liquid produced from base materials that do not require saccharification?
A
A wine.
2
Q
What is the term for the fermented liquid that went through saccharification?
A
A beer.
3
Q
What is a wash?
A
A fermented liquid intended to be distilled into a spirit.
4
Q
What type of sugars are fermentable ?
A
Monosaccharides and Disaccharides
5
Q
What are two important examples of monosaccharides?
A
Glucose
Fructose
6
Q
What is an example of a disaccharide?
A
Sucrose
7
Q
What is another term of Polysaccharides?
A
Complex Carbohydrates.
8
Q
What are some examples of Polysaccharides that need conversion before alcoholic fermentation?
A
Starches (Grains and potatoes)
Fructans (Agave)
9
Q
What type of environment do yeasts prefer?
A
Acidic
10
Q
At what temperatures are yeasts active and able to ferment sugars?
A
41-86°F (5-30°C)
11
Q
What nutrients do yeast require?
A
Fermentable Sugars
Nitrogen
12
Q
What is an example of a raw material with low levels of nitrogen that may require supplementation?
A
Sugar Cane
13
Q
What can happen if the yeast does not receive the nutrients it needs?
A
Could result in a “stuck” fermentation.
14
Q
What may happen with a stuck fermentation?
A
Other microorganisms could start to consume the sugars and create unpleasant aromas (also known as spoilage). Also eat some of the sugar and reduce the amount of ethanol that can be produced.
15
Q
What are the 3 main outputs of fermentation?
A
Ethanol
Carbon Dioxide
Heat.
16
Q
What are some additional outputs from fermentation?
A
Methanol
Fusel Alcohols
Fatty Acids
Esters
Sulfur Compounds
17
Q
What type of raw material yield much higher levels of methanol during fermentation?
A
Fruit juices.
18
Q
Why do fruit juices produce higher levels of methanol than other raw materials?
A
Due to their high level of pectin.
19
Q
What are heavy or higher alcohols?
A
Another term for Fusel alcohols.
20
Q
What are Fusel Oils?
A
A mixture of fusel alcohols, fatty acids, and esters.
20
Q
How does the boiling point of Fusel Alcohols compare with that of ethanol?
A
Fusel alcohols have a higher boiling point than ethanol.
21
Q
What is the most widely used strain of yeast in the production of alcoholic beverages?
A
Saccharomyces Cerevisiae.
22
Q
What is the term used for acids produced by yeast during fermentation?
A
Fatty Acids.
23
Q
How is fermentation usually initiated by distillers?
A
Distillers add cultured yeast to a small container with sugary liquid. The yeast rapidly divide, and the fermenting liquid is transferred to a larger vessel. The process may be repeated a few times before being added to the fermentation tank.
24
What are two categories of spirits where ambient/wild yeast is commonly used?
Mezcal and Baijiu
25
What are the two main categories of fermentation sequence?
Sequential Fermentation
Parallel Fermentation
26
What is sequential fermentation?
A fermentation process where all of the fermentable sugars that the yeast will ferment are present at the start of fermentation.
27
What is Parallel Fermentation?
A fermentation process where starch is converted to fermentable sugars while fermentation is taking place.
28
Is whiskey fermented using sequential or parallel fermentation?
Sequential, however, the conversion of starch into fermentable sugars is generally not complete before fermentation begins.
29
Why is the conversion of starch into fermentable sugars not fully complete before fermentation begins in whisky production?
The sugary liquid is vulnerable to spoilage while being converted. Once most has be converted, alcoholic fermentation will be started.
30
In which spirits is the Parallel Fermentation used?
Shochu, Baijiu, and Soju.
31
What is used in Asian spirit production to produce the amylases needed for the conversion of starches to fermentable sugars?
Filamentous fungi.
32
What is semi-solid-state fermentation?
Fermentation in a liquid that contains a high level of starch solids.
33
What spirits are produced using semi-solid-state fermentation?
Some Baijiu and all shochu
34
What is solid-state fermentation?
The use of only grains for fermentation.
35
What beverages are produced using Solid-State Fermentation?
Only Baijiu.
36
How do yeasts populate the grains in solid state fermentation?
The small pieces of solid materials are wet. Yeast grows through the grains by cell division.
37
Describe the containers used for most solid-state fermentations.
Sealed containers, most commonly pits in the ground.
38
How long can solid state fermentations take to complete?
Up to two months.
39
What distillers might actively encourage the creation of pronounced bacterial aromas?
Some producers of Baijiu.
40
Why might some distillers allow the growth of bacteria after fermentation?
Some distillers, including some Scotch whiskey and sugar cane spirit producers, encourage some bacteria growth to add complex aromas.
41
What is starch?
A complex carbohydrate composed of glucose molecules.
42
How is starch formed?
It is formed in plant cells when individual glucose molecules are bonded together and water is released.
43
What must happen for starch to be converted into fermentable sugars?
The starch must be broken down into glucose by separating the glucose molecules in the plant cells.
44
What is Modification?
A process used for grains, where the protein net storing the starch granules is broken down so that they can be converted into glucose.
45
Is modification necessary for potatoes?
No, the starch is stored in living cells, not a "protein net".
46
What is gelatinization?
The stage of starch conversion where starch granules unroll and dissolve in water.
47
What are the three stages of starch conversion?
Modification, Gelatinization, and Enzymatic Hydrolysis.
48
How is Gelatinization accomplished?
Slowly with water, can be sped up with heat.
49
How is Modification accomplished?
Grains accomplish it using enzymes, distillers can achieve the result by applying heat.
50
What is Enzymatic Hydrolysis?
The use of enzymes to convert starch into glucose through hydrolysis, which breaks the bonds that hold the starch together, converting it back into glucose.
51
Why are only a small number of Amylases needed to accomplish Enzymatic hydrolisis?
They are not used up or destroyed in the reactions so they can complete the same task repeatedly.
52
What effect does temperature have on Enzymatic Hydrolysis?
If the temperature is to cold, the amylases will become dormant. If too hot, they become less efficient and are eventually destroyed.
53
What are the two different approaches to converting starch used in the west?
Malted grains
Unmalted grains.
54
What are the four main structures of grains?
Bran
Husk
Germ
Endosperm
55
What are some examples of "pseudograins"?
Buckwheat (Soba)
Quinoa
56
What is a bran?
The hard, thin, edible protective layer of whole grains like wheat, oats, rice, and rye.
57
What is a husk?
The inedible hard, outermost covering of a grain.
58
What is the germ of a grain?
The embryonic plant that grows when conditions are warm and damp enough. Called germination.
59
What is the endosperm of a grain?
The part of a grain where starch granules are stored.
60
What are the three stages of the process where a sugary liquid is made from malted barley?
Malting
Milling
Mashing
61
What is malting?
The process where modification takes place and the grain's amylase enzymes are released.
62
What is mashing?
The process where gelatinization and enzymatic hydrolysis take place.
63
How does mashing take place while using malted barley?
The grist is mixed with warm water to gelatinize the starch and achieve enzymatic hydrolysis.
64
How does mashing take place while using unmalted grains?
The cooked grains are mixed with amylase enzymes to achieve enzymatic hydrolysis.
65
Is barley the only grain that can be malted?
No, grains like corn, rye and wheat can also be malted, but it is rare.
66
What is green malt?
Barley that has started to swell and grow roots.
67
When is green malt kilned?
Once the roots have grown about as long as the length of the grain of barley.
68
What is green malt called after it has completed the kilning process?
Malted barley.
69
What happens if kilning is started too early?
The protein net may not be fully broken down, so some of the starch will be difficult or impossible for the enzymes to access.
70
What happens if kilning is started too late?
Too much of the starch will have been converted into glucose and consumed by the plant, so the amount of fermentable sugars, and therefore alcohol, is reduced.
71
Why is milling necessary?
Milling makes the starch more accessible during mashing.
72
What is Grist?
The smaller grain pieces resulting from milling.
73
At what temperature does mashing take place?
Between 63-64°C (145-147°F)
74
About how long does mashing take place when using malted grains?
About one hour.
75
What happens after mashing is complete?
The sweet liquid (wort or mash) is drained off from the bottom of the vessel. The wort is then cooled and sent to the fermenter. Solids are then sparged.
76
What is sparging?
The process of spraying the solids left after the wort (mash) is drained off with hot water at least twice, tow capture any remaining starch or fermentable sugars.
77
Why is hot water used during sparging?
To ensure that all remaining starch is gelatinized.
78
What is the malt of choice in Scotland?
Distiller's malt.
79
Why is Distiller's malt favored in Scotland?
It maximizes the yield of alcohol that can be achieved from the grains. They are pale in color and most enzymes and starch are preserved in the malt.
80
Why are specialty malts generally avoided in Scotland?
Due to the high heat, many of the enzymes and starch become unavailable for fermentation.
81
Where and why are some specialty malts used?
Occasionally in the US, where distillers overlook the loss of yield in favor of the extra flavors that can be contributed to the spirit.
82
What happens to the malt when excess heat is applied?
Roasted, chocolate aromas are created, caramel and nutty flavors can be created. Enzymes and starch can be destroyed.
83
What are the three stages for making a fermentable liquid from unmalted grains?
Milling
Cooking
Mashing
84
What is the Cooking stage in the pre-fermentation process?
The grains are heated to achieve modification and gelatinize the starch granules.
85
What determines the operational temperature of the cooker during pre-fermentation?
It depends on the grains being used, as they have different optimal temperatures for gelatinization, so different grains are added at different temperatures. The grain with the highest gelatinization temperature is added first, and the one with the lowest last.
86
What type of amylase enzymes are added during mashing using unmalted grains?
Either bought-in (exogenous) or malted barley (which would make up a small percentage of the mash).
87
What type of malted barley would be used during the mashing process for unmalted grains, and why?
Special varieties of barley that produce high levels of enzymes due to the small quantities added.
88
Why are varieties of barley with high levels of enzymes used during the mashing process for unmalted grains?
Since the malted barley makes up such as small amount of the mash, it helps to speed up the enzyme production and reduces the risk of spoilage.
89
How long does mashing take place when using unmalted grains?
About 45 minutes.
90
How must the starch in potatoes be converted to fermentable liquids?
The potatoes must be cooked to gelatinize their starch, and exogenous enzymes must be added to convert the start into sugar.
91
What is different about a potato compared to a grain relating to enzyme release?
Potatoes do not release all of the amylase enzymes at the same time, the enzyme release happens progressively.
92
What enzymes are used in Asia for converting starches to fermentable liquids?
Filamentous fungi
Bacteria (occasionally)
93
What are the three steps used in Asian traditions for converting starch to fermentable material?
Cooking of starchy material
Fungi grown on small batch of material
Small batch added to gelatinized starchy material.
94
What is Qu?
The Chinese name for the starchy solid block of material used for cultivating the fungi used for converting starches to fermentable materials.
95
What is Nuruk?
The Korean name for the starchy solid block of material used for cultivating the fungi used for converting starches to fermentable materials.
96
What is Kōji?
The Japanese name for the starchy solid material grown on individual grains used for cultivating the fungi used for converting starches to fermentable materials.
97
How do the fungi used in Asian starch conversion grow?
Through their food, which is digested outside of their bodies and then absorbed.
98
What is saccharification?
The conversion process used to convert grains or starches into a fermentable form of sugar.
99
What process is necessary to convert grains and starchy materials to a fermentable form?
Saccharification.
100
How is saccharification typically accomplished?
By heating the starch to trigger production of enzymes that cause the conversion to sugars.
