1. Main stages in beer production

• malting

• milling

• mashing

• lautering or filtering

• boiling

• fermenting

• conditioning

• filtering

• packaging

2. Describe row materials needed for beer production

barley, in the form of malt

hops : the female flower of the hop vine is used as a flavouring and preservative agent. The flowers themselves are often called “hops”

yeast : top cropping yeast can produce higher alcohol concentrations and in higher temp., 16-24oC, produce fruiter, sweeter beers. Ex. S.cerevisiae. bottom cropping yeast ferment more sugars, creating a dryer beer, and grow well at low temp. Ex. S. pastorianus

water: the best water for brewing beer and the most prized is from natural sources which contain elements not found in other water sources. Two of the major elements are Ca and Mg. These two add the hardness and a desirable mouth feeling and also aid many of the biochemical processes taking place during brewing

malted wheat

oats

3. What does it mean top and bottom fermentation

Top (ale), fermented with yeast Saccharomyces cerevisiae although there is also spontaneously fermented beer with wild yeast or/and bacteria.

Warm fermentation: between 15-20oC, occasionally as high as 24oC. S.cerevisiae generally form a foam on the surface of the fermenting beer, as during the fermentation process its hydrophobic surface causes the flocks to adhere to CO2 and rise

Bottom (lager) fermented with yeast Saccharomyces pastorianus. Lager is beer that is cool fermented at around 6-12oC. Sediment at the end of fermentation at the bottom of fermentor and is stored for 30 days or lager close to the freezing point.

4. What is the aim of malting and how malting is done

Malting is the process where the barley grain is made ready for brewing in three steps, which help to release the starches in the barley.

• during steeping, the grain is added to a vat with water and allowed to soak for approximately 40 hours.

• During germination, the grain spread out on the floor or in special boxes in the germination room for around 5-7days. The goal: allow the starches in the barley grain to breakdown into shorter lengths. After that the grain is referred to as green malt

• kilning, the green malt goes through a very high temp.drying in a klin. The temp.change is gradual so as not to disturb or damage the enzymes in the grain. After this final part we have malt as a product.

5. What does mashing (ugniatanie) mean?

Mashing in is a second step in the brewing process. The hot water is used as an input and the mash is the product.

In brewing and distilling, mashing is the process of combining a mix of milled grain (typically malted barley with supplementary grains such as corn, sorghum, rye or wheat), known as the "grain bill", and water, known as "liquor", and heating this mixture. Mashing allows the enzymes in the malt to break down the starch in the grain into sugars, typically maltose to create a malty liquid called wort.

6. Chemical and physical changes during wort (brzeczka piwna) boiling with hops (chmiel)

Hops:

• add bitterness

• act as a natural preservative, though other flavourings such as herbs or fruit may occasionally be included

The wort mixture is boiled in order to sanitize as well as extract the flavor and aroma from the hops, which are added to the wort at set times in two parts. Hop cones contain resins, which provide the bittering and take a long boil to extract, and oils, which provide flavor and aroma, but evaporate quickly. Generally speaking, hops provide the most flavoring when boiled for around 15 minutes, and the most aroma when not boiled at all

7. why young beer has to be maturated?

During the maturation:

• The off-flavour, diacetyl is assimilated by yeast cells and degraded to below the taste threshold,

• The colloidal stability of the beer is greatly improved due to precipitation of protein-tannin complexes, which are only sparingly soluble at low temperature,

• Final stabilisation removes further amounts of proteinaceous matter and/or tannins,

• The residual yeast cells have been removed,

• Oxygen uptake is reduced as much as possible and beer is adjusted to the correct carbon dioxide contentand

8. shortly describe main enzymes involved in brewing

• β-amylase works at the end of the starch chain and “bites off” two sugar at a time. The disaccharide that it produces is maltose - the most common sugar available from barley malt.

• α- amylase enzyme break apart starch chains at almost any point (1-4 α) in the starch chain. As a result, it usually breaks long chains 100 to 500 sugars in length off of the starch molecule.

• Proteases digest proteins by breaking down the bonds between amino acid. Both peptides and amino acids result from the breakdown of these proteins play an important part in yeast metabolism and head retention.

• β-glucanase acts on gum-like materials which increase viscosity of the wort during lautering and lead to slow run-offs. Î’-glucans tend to be soluble in hot wort but insoluble in cold beer and thus may contribute to chill haze.

9. chemistry and stages of yeast alcoholic fermentation

Ethanol production

C₆H₁₂O₆2CO₂+2C₂H₅OH

2ATP, 61kJ/glucose, 26%efficiency

During the primary fermentation, the fermentable sugars, mainly maltose and glucose are converted to ethanol and carbon dioxide by the brewing yeast.

The main factors affecting fermentation performance and beer quality

1. The chice of yeast strain

2. The condition of the yeast at the time of pitching

3. The amount of yeast added to the wort

4. The distribution of the yeast in the fermenting wort throughout the fermentation, and the size and geometry of the fermentation vessel

5. Aeration

6. Wort composition and pH

7. Fermentation temperature and pressure

Warm fermentation

Yeast such Saccharomyces cerevisiae are generally fermented at warm temperatures between 15-20°C occasionally as high as 24°C. they generally foam on the surface of the fermenting beer, as during the fermentation process its hydrophobic surface causes the flocs to adhere to CO₂ and rise; because of this they are often referred to as “top fermentating”

Cold fermentation

Lager is beer that is cool fermented at around 6-12C, sediment at the end of fermentation at the bottom of fermentor and is stored for 30 days or longer close to the freezing point. Saccharomyces pastorianus is used in the brewing of lager

10. how fermented products- wine can be classified

According to row materials and technology:

• The grape wine

• The fermented alcoholic beverages

• Fruit wines- made by alcoholic fermentation of fruits or its juices and often with addition of water, saccharose or spirit

• Flavored wines-made from grape of fruit wine with addition of spirits and natural flavored herbs and spices

• Honey wine (mead)- made by alcohol fermentation from natural honey diluted with water and fruit juice also often with addition of herbs and spices

• Wine derivatives- alcoholic beverages with 50% minimum share of wine or honey wine

• Wine like beverages- with minimum 20-45% share of natural fruit juices

• Low alcoholic beverages-made in part by alcoholic fermentation of grape or fruit juiced or by partial removal of alcohol from grape wines.

According to taste and aroma

• Sparkling wine

• Artificially carbonated wine

• Aromatized wine wine of mass

According to color

• White

• Pink

• Red

According to sugar content

• Dessert wines (white, red)

• Table wines (white or red)

According to alcohol content

• Light

• Medium

• Strong

11. Compare chemical composition of fruit juices and barley wort

• Sugars - glucose, fructose, sucrose

• Organic acids - citric, malic, tartaric, lactic, acetic

• Nitrogen substances - proteins

• Pectins - poligalacturonic acid and ramnose

• Tannins - gallus acid, tannins, catechins, anthocyanins

• Aroma substances - esters, alcohols, aldehydes, ketones, hydrocarbons

• Minerals - ash 0,5% (K, Ca, Mg, Na, P, S, Cl)

• Witamines - C, A (caroten), B group (B1, B2, PP).

12. Main processes during winemarking

Stages:

• harvesting and transportation

• washing and selection

• crushing and pressing

• fermentation

juice

pomace

• first racking

• aging, maturation and fining

• filtration and pasteurization

• bottling

13. Why SO₂ is used in winemarking

Sulphur dioxide is the most widely used additive in wine making with role to inhibit or kill unwanted yeasts and bacteria and to protect wine from oxidation.

oxidation is the reaction of wine with oxygen. it can alter its colour and odour and is often dismisses as a fault.

SO₂ is added at several points in the vinification and is present in the finished wine as sulphites. there 3 points where sulphur dioxide is commonly used: crushing, fermentation, bottling.

14. What we expect from wine's yeasts

- alcohol toleration

-can establish a viable population in an environment of high sugar (190-270 grams per litre) and high acidity

-are resistance to CO₂ concentration

-are strong and consistent fermenters even at cold temperatures

-they ferment quickly and only stop when all sugars have been utillised

-are more tolerant to sulfur dioxide than other yeasts and bacteria

-they produce wine like aroma and flavor characters

-special yeast for sparkling, sulfited, red (tannins), different fruits

15. Factors effecting the course of fermentation

-carbon sources (monosaccharides)

-nitrogen sources (amino acids, ammonium salts)

-minerals (Mg, K, Zn, Co, J, Fe, Ca, Cu, P, S)

-alcohol (inhibition at high concentration)

-carbon dioxide (high level can stopped yeast growth)

-acids (low pH reduce fermentation)

-growth factors (biotin, inositol, nicotinic, acid, thamine)

-tannins (in some cases inhibit yeast growth)

-temperature (optimum 22-27C)

-oxygen (essential for yeast growth, absent during fermentation, controlled during maturation)

16. What has to be done with wine after fermentation

*After fermentation wine has to be storaged, while this it is aging.

-oak containers are preferred

-tanks must be filled up and sealed to prevent acetification

-the bouquet develops (row materials, fermentation, maturation)

-yeast odor and harsh taste disappear

-temperature is lowered to 5-12 C for dry and semi dry wines, to 18C for sweet wines and also for red wines

-correction of acidity occurs

-process last from few to years with several yeast racking (red table wines 1-4 years, white table years 1-2 years, polish fruit wines popular 3 months and mark 6 months)

*accelerated maturation:
-cooling
-refrigeration
-slow oxidation
-heating (pasteurization)
-exposure to sunlight, UV light

*wine stabilization and filtration
Clarification of wines by fining with addition of substances which react with tannins, acids, proteins (gelatin, casein etc.).

17. Give a short description of main types of fortified wines.

We can discern a main 3 basic groups of fortified wines: Port, Sherry and Madeira (final alcohol level 15-22%)

Port - is made mainly with red grapes. Is a kind of sweet wine. Fortified to 20% by the addition of a neutral grape spirit (brandy).

Sherry - mainly white, dry wine. Brandy is adding to the wine after fermentation.

Madeira - can be made like Sherry (the sugar is almost fully fermented before the brandy is added) or closer to the way like Port is made (interrupting the fermentation with grape spirit leaving residual sugar in the Madeira).

1. Enumerate and briefly characterized functional additives used in bakery technology

• Enzymes

• Emulsifiers

• Oxidizing and reducing agents

• Hydrocolloids

• Acidifiers

Applied to:

• improve sensory characteristic of the product, taste, smell, appearance, volume, texture

• extend shelf life

• improve machine ability of the dough

• raise profitability: shorter production process, lower workload, reduce number of fermentation vessels, replacement of expensive ingredients

Enzymes- amylases (α and β)- fungal, bacterial enzymes or malt- good dough and bread texture (fermentable sugar),

Proteases- bacterial and plant enzymes- better dough elasticity and extensibility, shorten mixing and proofing time

Oxidoreductases- lipoxidases- strengthened dough structure, flour bleaching

Emulsifiers- surface active agents able to form starch-protein-fat-water complex

• ionic- improved dough handling and gas retention

• non-ionic- longer bread shelf life

• lecithin- plant oils or eggs isolate- increase dough nie mam zapisane co dalej prosze aby ktoÅ› uzupeÅ‚niÅ‚

Oxidants- potassium brodate, ascorbic acid- increase of flour hydration, improved dough reological properties and gas retention, flour bleaching

Hydrocolloids- substance that form a gel with water

• plant secretions or extracts, powdered seeds,

• microbiological gums

• synthetic gum

Increase of dough yield, prolonged shelf life, improved crumb quality

Organic acid and their salts:

• lactic, citric, tartaric or acetic acid and their salts

• dried sourdough with acids addition

• quick dough acidification

2. Explain the role of bakery starter cultures

• Initiation of the fermentation process

• Obtaining the desired baking parameters of dough

• Due to the biochemical changes in the fermented flour

• Stability of the fermentation process

• Shortening and simplifying sourdough production

• Obtaining the unique and very attractive taste and flavor of the bread

• Bread of high nutritional value

• Reduction or elimination of artificial improvers and preservatives

• Repeatability of bread quality

• Prolonged shelf life or sourdough bread

3. Indicate and briefly characterized the new technologies in bread production

• Dried sourdough- dried full sour (direct dough preparation, used as a starter culture)

• Liquid sourdough- rich in aroma, easy to handle

• Delayed dough fermentation (retarded dough)- delay in dough fermentation caused by low temp. application

• Delayed bread baking- separation (in time and/or in place) between the dough preparation and the baking by freezing of semi-products

• Dried sour dough- sourdough prepared with a high yield >200, preserved by water removal

• Freeze drying (lyophilisation)- dehydration process, base on water evaporation from the solid phase (ice), weaker aroma, removal of volatiles

• Fluid bed drying - heat supplied by hot air, formation of aroma compounds typical for baked potatoes

• Prolonged fermentation in ambient temp- lower yeast dosage (1,5-2%), ambient temp, leaving time 3-6h.

• Blocked dough leavening- nie zapisaÅ‚am bo pewnie nie daÅ‚am rady

• Blocked incomplete dough leavening- fermentation in temp 25C, obtaining 1/3 -3/4 of full volume, blockade at temp ponownie szkoda ze szybciej nie przerzucaÅ‚a slajdów.

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