THE CAYMAN ISLANDS BREWERY

1. THE CAYMAN ISLANDS BREWERY The Science of Brewing Cecilia Cruz Palma

2. Content overview • Company Introduction • Brewing step by step • Raw Materials • Malt • Hops • Wort Production • Mashing • Lautering • Boiling • Fermentation • Yeast

3. CIB • The Cayman Islands Brewery was launched in 2007 • The brewery was designed and modernized with help of Brewtech specialists, a German brewing consultant company • The brewery now produces 4 lager beers and one bock beer • Go to: www.cib.ky

4. Raw Materials • Three major raw materials: • In many countries also syrups, sugar, rice used

5. Malt • Germinated grains • For beer production mostly barley malt is used Hordeumvulgare Source: www.freefoto.com Source: www.crc.dk

6. Malting overview Source: Rath

7. Malting overview Source: Rath

8. Germination • Water uptake during steeping • Hormones called gyberilic acid released • Enzyme production activated Aleurone layer Embryo Endosperm Source: Methner

9. Enzymes • Enzymes are active proteins which catalyze reactions • Enzymes are substrate specific and their activity depends mainly on: • Temperature • pH • Substrate concentration Source: www.biologyguide.net

10. Barley enzymes • Germination enzymes in barley make possible the degradation of higher molecules • There are three major modification processes during malting and brewing

11. Cytolysis and Proteolysis • Breakdown of starch granule’s cell wall and protein matrix • Most important processes of malting as path needs to be clear for further breakdown enzymes

12. Cell wall structure • Cell wall is built by different components Protein middle lamella Source: Bamforth

13. Proteins • Proteins are chains of amino acids folded together into stable 3D structures • Proteinases breakdown proteins into short peptides • These peptides are further degraded by peptidases into free amino acids • Amino acids are “Free amino nitrogen” (FAN) a very important nutrient for the yeast during the fermentation

14. Cell wall structure • Cell wall is built by different components Hemicelluloses Source: Bamforth

15. Short reminder • Sugars act as building unit for many polymers • Two different structures, here in example of glucose: • Leads to two different glycosidic bonds α-Glucose β-Glucose α-glycosidic bond β-glycosidic bond

16. Hemicelluloses • Are the major component of the cell wall and give to it its stable hard structure • Hemicelluloses in barley are: • β-glucans • Pentosanes • Breakdown of hemicelluloses is done by many different enzymes formed through germination

17. β-Glucans • Unbranched chain of cellobiose and laminaribiose

18. Pentosanes • Branched chain of xylan with arabinose • Ferulic acid can bind to arabinose and creates a more stable structure

19. Amylolysis • Starch is built by most plants as an energy reservoir • Amylolysis is low during germination and takes place mainly during mashing • There are two main enzymes doing this process • α-Amylase • β-Amylase

20. Starch • Starch consists of two chains of glucose units • Amylose • Unbranched • α(14) Glucose • Amylopectin • Branched • α(14) Glucose • α(16) Glucose

21. Amylolysis • Both enzymes cleave α(14) glycosidic bonds • α-Amylase is an endoenzyme, works within the starch chain forming short oligosaccharides • β-Amylase is an exoenzyme, works only from the ends and forms Maltose, Glucose & other simple sugars α-amylase β-amylase

22. Malting overview Source: Rath

23. Kilning • The process of drying the malt with hot air • High moisture content leads to fast spoilage of the grains • The heat causes: • Water evaporation • Formation of color and aroma compounds • Temporary inactivation of enzymes Source: www.weyermann.de

24. Malting overview Source: Rath

25. Malt quality control • Several parameters have to be controlled at the brewery before accepting the malt • Hand bonitierung • Insects, moulds • Color, smell • Water content • Cell wall modification • Friabilimeter • Calcofluor staining • Protein content

26. Hops • Plant giving beer its bitter profile Source: Barth

27. Hops components

28. Hops products • Nowadays cones are processed into different products • Worldwide mostly pellets are used Hops cones Hops extracts Hops pellets

29. Brewing overview Source: Rath

30. Mashing • Milled malt is combined with warm water so that malt enzymes are reactivated • Temperature of the mash must be set according to the optimal working temperature of the enzymes Amylolysis Proteolysis and cytolisis Source: Kunze

31. Mashing • Nowadays malts are so well modified that starch degradation is the main aim of mashing • Phases of starch degradation: • Water uptake of starch granules • Swelling of granules until bursting • Viscous solution formed • Gelatinization of starch • Stable starch molecules disintegrate • Enzyme attack begins • Saccharification • Fermentable sugars formed

32. Brewing overview Source: Rath

33. Lautering • Filtration process to separate the soluble malt liquid called wort and the rest of solid grains • The fraction of fermentable sugars in the wort is called extract • Filter agent are the husks of the malt • More water can be added to increase the extraction Source: Huppman

34. Brewing overview Source: Rath

35. Boiling • Boiling assures: • Evaporation of water thus extract increase • Coagulation of unwanted proteins • Formation of color and aroma substances • Isomerization of α-acids into soluble iso-α-acids

36. Brewing overview Source: Rath

37. Fermentation • The cold wort is transferred to the fermentation cellar • The wort is then called young beer once the yeast is “pitched” and the fermentation process starts • Yeast are eukaryotic unicellular fungi used in the industry for brewing and baking • The yeast used for brewing beer is from the Saccharomyces family

38. Yeast metabolism • Yeast is able to do both respiration and alcoholic fermentation • Wort aeration is done at the beginning to assure yeast growth • After oxygen is consumed yeast starts forming ethanol

39. Yeast metabolism • Ethanol and CO2are the main products of alcoholic fermentation • Other by-products IMPORTANT for the flavor and aroma profile of the beer are also formed mostly during lagering • Such as: • Aldehydes • Higher alcohols • Esters

40. Yeast metabolism • It is important to check the actual state of the yeast • For this two parameters are controlled: • Vitality: physiological state of the yeast how active is my yeast? • Viability: rate of dead cells in the mixture  how alive is my yeast?

41. Brewing Yeast • Two types of brewing yeast • Top Fermenting • Top fermentig brewing yeast is from the species • Saccharomyces cerevisiae • Can both reproduce sexual and asexually • Wanted in the brewing process is a diploid asexual reproduction

42. Brewing yeast • Bottom fermenting • Species S. carlbergensisisan hybrid of S. cerevisiaeand S. monascensis • Is aneuploid, has a complex and unusual chromosome number • Lost the capability to do meiosis thus reproduce sexually

43. Budding • Sporulation has to be repressed so that no mutants and no unwanted products are formed • To do so yeast has to grow under normal optimal conditions • Yeast then multiplies by budding Source: www.braulots.de

44. Fermentation types • Top fermenting • Fermentation follows more rapidly at higher Temp. 13-19°C • High content of fermentation by-products so stronger flavors Ales, Stout, Kölsch, Wheat beer • Bottom fermenting • Fermentation follows slowly at lower Temp. 10-14°C • Lower content of fermentation by-products so plainer flavor Pilsener, Lager, Bock beer

45. The Cayman Islands Brewery Thank you for your attention… Cheers!