Ọrịa biya
Mmejọ biya ma ọ bụ ntụpọ bụ mmebi ekpomeekpo sitere na mgbanwe kemịkal nke ogige organic na biya n'ihi usoro mmepụta na-ezighi ezi ma ọ bụ nchekwa na-ezighi ezi. Chemicals ndị nwere ike ịkpata ntụpọ ụtọ na bia bụ aldehydes (dị ka dactyl organic acids), lipids, na ogige sọlfọ. Obere mgbanwe dị n'ime ihe ndị na-emepụta gbaa ụka nwere ike iduga na mkpokọta nke otu ma ọ bụ karịa n'ime kemịkalụ ndị a na-ada na mpụga ọkọlọtọ, na-emepụta ntụpọ ekpomeekpo. Ọ ga-ekwe omume na n'oge usoro malting, mmebi microbial nwere ike ime, nke na-eduga ná mfu nke ụtọ biya.
Diacetyl
[dezie | dezie ebe o si]Diacetyl bụ kemịkal a na-emepụta na yeast n'oge fermentation ma mesịa bụrụ nke a na-amịkọrọ. Ọ bụrụ na okpomọkụ dị n'èzí n'oge fermentation dị ala karịa 26 , diacetyl na-amịkọrọ n'ụzọ na-ezughị ezu, na-akpata ọnụ ụzọ nke ihe na-erughị 0.04 mg / lita na biya, nke na-enye biya ahụ mmetụta ọnụ yiri cheese cream.[1] Ọsụsọ a ga-esi na ya pụta ga-anọgide na-aga n'ihu. Ebe ọ bụ na ire ure nke α-acetolactate na-emepụta diacetyl buru ibu, enwere ike izere ntụpọ nke ụtọ biya nke diacetyl kpatara site na isi ihe ahụ ma sachaa ya tupu fermentation yeast. Mmanụ ahụ kwesịrị izere mmetụ oxygen mgbe ọ na-amalite ịgba.[2] Ọ bụrụ na e bulie okpomọkụ site na 2°-3° n'ime nkeji 2 nke njedebe nke usoro ịgbaze, nke a na-enye ohere ka ihe iko achịcha ahụ gbakee ngwa ngwa.
Nri Risotto
[dezie | dezie ebe o si]Beer nwere ike ịnwe ụtọ nke osikapa na-atọ ụtọ ma ọ bụrụ na oke diacetyl na biya ahụ gafere oke ụtọ ya dị ala. Maka lagers na-acha ọkụ, ihe dị na diacetyl dị n'okpuru 0.1 mg / L; maka biya dị elu, ọ ga-anọgide n'okpuru0.05 mg / L. Ihe ngwọta bụ ịbawanye nitrogen a-amino nke wort n'ụzọ kwesịrị ekwesị. N'ozuzu, a na-achịkwa ọdịnaya nke 12P wort ka ọ bụrụ 180 ± 20 mg / L.[3] N'ihi na ihe ndị na-ebute diacetyl na ihe ndị ọzọ na-eme ka ihe na-eko achịcha na-emepụta ihe n'oge ọmụmụ ihe na-ekeko achịcha, enwere ike ibelata ọnụego mmụba nke yeast site na ịnakwere usoro ihe dịka inoculation na-ekpo ọkụ, inoculum, na fermentation na-ekwo ọkụ, yana ịbawanye okpomọkụ fermentation na njedebe nke isi fermentation.
Acid ndị na-akpata mmebi biya
[dezie | dezie ebe o si]Acids ndị a na-emepụta n'oge fermentation nke ihe ndị a na'emepụta ma ọ bụ n'oge na-agbanye site na yeast dị n'ọtụtụ na biya. Mgbe acid karịrị 170 mg / lita, uto siri ike nke yogọt ma ọ bụ ose nwere ike, na-akpata nnukwu ntụpọ na biya. Ebe nrụọrụ weebụ dị ọcha, na-agwakọta ụdị yeast maka ihe na-erughị awa abụọ, na idebe okpomọkụ fermentation dị ala karịa 50 niile na-enyere aka belata acid dị na biya. Iji ihe ndị na-abụghị akara na ngwá ọrụ na-egbochi nje bacteria ka ọ ghara ịba na ihe na-eme ka ọ na-agbanye, si otú a na-emetọ ihe iko achịcha n'ime usoro ahụ.[4]
Octanoic
[dezie | dezie ebe o si]Octanoic acid (caprylic acid) bụ acid fatty na- emepụta site na metabolism nke yist n'oge ịgba ụka..Mgbe odinaya octanoic acid dị na biya karịrị 4-6 mg / L, biya ahụ ga-enwe ụtọ dị ụtọ oseose nke ukwuu. Nchekwa biya na gburugbu 26 ga-ebelata ụtọ ụtọ. Ojiji yist ọhụrụ na mwepu nke biya na keki yeast ozugbo usoro ịgba ụka gachara na- edobe ọdịnaya octanoic acid dị n'ime ọnụ ụzọ.
Ebe a na-egbu egbu
[dezie | dezie ebe o si]Butyric acid . acid nke nje bacteria na-emepụta sirop maka biya, ma ọ bụ nwere ike ịmepụta n'oge mmepụta wort. Mgbe ọdịnaya butyric acid dị na biya karịrị 2-3 mg/lita, biya ahụ na-atọ ụtọ dị ka mmiri ara ehi metamorphic ma ọ bụ bọta rere ure. Iji zere nsonaazụ a, ekwesịrị idobe sputum acid n'elu 90 °F ma nwee obere kọntaktị na oxygen. Ebe mmepụta biya ga-adị ọcha. Ihe ndị dị na mpụga dị ka mmetọ mgbe a na-emepụta sirop nwekwara ike ịchịkwa ọdịnaya nke butyric acid. a.[5]
Isovaleric
[dezie | dezie ebe o si]Isovaleric acid bụ acid a na-emepụta site na ịgwakọta octanoic acid na oxidation nke alfa na biya, nke na-eme ka biya nwee ísì. Acid dị na biya n'oge sitere na 0.7 ruo 1 mg kwa lita. Ebe mmepụta ihe dị ọcha na ịdị ọcha na-ezere ịgwakọta nke caprylic acid na isovaleric acid. A na- echekwa Hops n'ime akpa ikuku na-enweghị oxygen ikuku na-egbochi nje nje.
Aldehydes
[dezie | dezie ebe o si]Acetaldehyde
[dezie | dezie ebe o si]Acetaldehyde na-eme ka biya na-atọ ụtọ dị ka apụl na-acha akwụkwọ ndụ akwụkwọ ndụ mgbe ọ gafere 5-15 mg / L.[6] N'oge a na-agbanye biya, ethanol dị na yeast nwere ike imetụta ikuku ma ọ bụrụ na echekwara ya n'ụzọ na-ekwesịghị ekwesị, na-eduga na mmeghachi omume oxidation nke na-agbanwe ya ka ọ bụrụ acetaldehyde. Iji gbochie mmepụta nke acetaldehyde, a ga-agbanye yist ọhụrụ na okpomọkụ kwesịrị ekwesị, na gburugburu ebe nrụpụta kwesịrị ịdị ọcha. Mgbe mmalite nke ịgbaze, iji ihe ndị dị elu na-eme ka ihe ndị ahụ ghara ịbịakwute ikuku oxygen. Ihe ndị na-egbochi ikuku nke ukwuu eji eme njem nwere ike belata ikuku oxygen na-abanye na biya.[7]
Phenols
[dezie | dezie ebe o si]Ọnụnọ nke phenols na biya bụ 0.05-0.55 mg / L, na biya nwere ọdịnaya phenolic karịrị ọnụ ọgụgụ a nwere ụtọ ilu na anwụrụ ọkụ. Iji mmiri pọmpụ, nke nwere chlorophenol ma ọ bụ mmiri chlorine dị ka ihe na-egbu nje, dịka mmiri ịsa ahụ na-eko achịcha nwere ike ibuli phenolic acid nke biya mgbe a ṅụsịrị ya. Enwere ike ibelata ihe dị na phenolic acid site na nzacha mmiri pọmpụ tupu o jiri ya mee ihe, yana site na ịhọrọ ihe na-abụghị chlorine disinfectants.
Hydrogen sulfide
[dezie | dezie ebe o si]Hydrogen sulfide na-emepụta ụtọ àkwá rere ure na biya. Ọtụtụ ụdị yist nwere ike ịmepụta hydrogen sulfide n'oge usoro ịgba ụka. A na-emepụta sọlfọ na hops, yana n'oge nrụpụta malt ma ọ bụ nkwadebe wort, n' agbanyeghị na usoro isi wort na-ewepụ ọtụtụ sulfides.[8] Ọnụ ụzọ nke hydrogen sulfide na biya bụ 4 μg / L. Iji ihe iko achịcha dị mma na wort oxidized zuru oke na-eme ka zinc ya dịkwuo elu ma belata hydrogen sulfide ya.
Sulfate nke ígwè
[dezie | dezie ebe o si]Ferrous sulfate na-akpata site na njikọ nke biya na ihe ndị dị n'ime ya n'oge usoro ịṅụ mmanya, na-akpatara metal ion leaching. Ọnụ ọgụgụ gabigara ókè nke iron sulfate nwere ike ime ka biya na-atọ ụtọ dị ka ígwè na ọla kọpa. Ọ bụrụ na sulfate iron na biya gafere 1.5 mg / L, ndị na-aṅụ mmanya ga-enwe mgbaàmà nke isi ọwụwa. Iji gbochie mmepụta nke iron sulfate, mmiri eji eme ihe maka ịṅụ mmanya na-emetụta mmeghachi omume nke metal ion. Containers maka biya a gwakọtara agwakọta na nke a gwakọchara agwakọta kwesịrị iji plastik dị mma, biya ekwesịghịkwa ịbịakwute containers na-emebi emebi.[9]
Dimethyl Sulfide
[dezie | dezie ebe o si]Dimethyl sulfide na-emepụta ụtọ mmiri ara ehi na-atọ ụtọ mgbe ọ gafere 0.025 mg / L na biya. Dimethyl sulfide sitere na sulfur-based organic compounds mepụtara n'oge mmepe malt.[10] Mmetụta nje bacteria n'oge fermentation nke yeast nwekwara ike ịkpata mmepụta nke dimethyl sulfide. Ọ bụrụ na biya ahụ na-eji malt nke sulfur-based organic compounds dị ka barley malt, ọdịnaya nke dimethyl sulfide ga-adị elu karịa ka ọ dị; ibelata ojiji nke ngwaahịa ndị dị otú ahụ na-egbochi ụdị nkwarụ a. Mmiri dị ukwuu n'ime wort nwekwara ike ịmepụta nnukwu ihe ndị sitere na sulfur, nke a nwere ike izere site na ịchekwa malt n'ebe kpọrọ nkụ. Ịsa wort na okpomọkụ dị elu maka minit 60 - 90 na-ewepụ 90% nke dimethyl sulfide.
Ọsụsọ
[dezie | dezie ebe o si]Mmanya biya oxidized nwere ụtọ dị ka akwụkwọ akụkọ ochie. Beer nke nwere 100% oxygen exposure nwere ọnụego oxidation kachasị ọsọ. Okpomọkụ bụ ihe ọzọ na-akpata oxidation, ebe ọ na-emepụta ọtụtụ oxygen na gburugburu ebe okpomọkụ dị elu.[11] Iji zere oke ikuku oxygen na biya, oghere dị n'isi maka biya dị na karama kwesịrị ịbụ ihe na-erughị otu sentimita. Ọ bụrụ na a ga-echekwa biya ahụ, a ga-edebe okpomọkụ dị n'ime akpa ya n'okpuru 50 . [12]
Thiols
[dezie | dezie ebe o si]Beer nwere thiols (nke a makwaara dị ka mercaptans) nwere ike ịnwe ụtọ yiri akwụkwọ nri rere ure ma ọ bụ ọwara na-esi ísì ụtọ. Ọnụ ụzọ maka mercaptans na biya bụ 1 mg / L. Mercaptans na-esite na autolysis na usoro fermentation nke ụdị yeast, ọ pụkwara ibute ọrịa nje anaerobic.[9] Enwere ike igbochi nke a site n'iwepụ biya ahụ n'ime yist izu anọ mgbe mmalite nke fermentation gasịrị, si otú a zere biya ahụ na-amị mercaptan site na yist nwụrụ anwụ.
Ìhè
[dezie | dezie ebe o si]Ịbụ onye ọkụ na-eme ka ọ na-atọ ụtọ. Ihe kpatara ya bụ mgbanwe kemịkal n'etiti riboflavin na hop alpha acid na biya n'okpuru ìhè okike ma ọ bụ ìhè aka.[12]
Ịchọpụta Njehie Beer
[dezie | dezie ebe o si]N'akụkọ ihe mere eme, ndị nyocha nwere ụzọ nke ha iji nwalee ogo biya ma ọ bụ nyochaa mmejọ ụfọdụ; otu ihe atụ nke a bụ ịnwale ma biya ahụ nwere shuga dị ukwuu, nke na-emetụta onye nyocha ahụ ịwụsa obere ego n'oche ya ma nọdụ ala iji hụ ma uwe ya ọ kwụ n'ofe. N'oge a, e nwere ndị nduzi na-akọwa ihe ị ga-achọ na otu esi achọpụta njehie ụfọdụ site na ụtọ, ísì, na ọdịdị / ọnụ.[13]
Hụkwa
[dezie | dezie ebe o si]Ebenside
[dezie | dezie ebe o si]- ↑ White. "Diacetyl Time Line".
- ↑ The role of diacetyl in beer. Drayman's (2016-06-12). Retrieved on 2019-05-31.
- ↑ Controlling Diacetyl. Brew Your Own. Retrieved on 2019-05-17.
- ↑ Temperature Factors - How to Brew. howtobrew.com. Archived from the original on 2019-05-25. Retrieved on 2019-05-31.
- ↑ The Oxford Companion to Beer Definition of butyric acid, (en). Craft Beer & Brewing. Retrieved on 2024-04-27.
- ↑ Common Off-Flavors - How to Brew. web.archive.org (2023-04-24). Archived from the original on 2023-04-24. Retrieved on 2024-04-27.
- ↑ Oxygen's Role in the Fermentation of Beer | MoreBeer. www.morebeer.com. Retrieved on 2019-05-31.
- ↑ Micet. Guide to beer off-flavors: hydrogen sulfide - Micet Craft Brewery Equipment (en-US). Retrieved on 2024-04-27.
- ↑ 9.0 9.1 18 Common Off Flavors In Beer (And How They're Caused). Kegerator.com (2016-07-01). Retrieved on 2019-05-31.
- ↑ Dimethyl Sulfides (DMS) in Home Brewed Beer | Home Brewing Beer Blog by BeerSmith™. beersmith.com. Retrieved on 2019-05-31.
- ↑ (January 1987) "Continuous ethanol fermentation by beer yeast". Journal of Fermentation Technology 65 (1): 116. DOI:10.1016/0385-6380(87)90078-1. ISSN 0385-6380.
- ↑ 12.0 12.1 Beer bottles: The answer is not clear. Brews News (2010-08-07). Retrieved on 2019-05-31.
- ↑ Barnes, Thomas. "The complete beer fault guide v. 1.4." (2011).