Indlela yokubulala amaqhiwani ekudleni ngokukukokisa isikhatjhana bese kuyapholiswa ebizwa nge-pasteurisation ngesikhuwa yasungulwa ngu-Louis Pasteur, usosayentsi we-France. Wafunyana bona ukukokisa ibisi imizuzwana ngamazinga aphezulu womtjhiso ubese ulipholisa msinya ngaphambili kobana ulifake ebhodlelweni nofana emaphaketheni kungalenza lihlale isikhathi eside lifretjhi.
Muva waragela phambili wasebenza ngebhiya ngo-1873, wenza imvumo yangokomthetho yendlela yokwenza ye-pasteurisation yebhiya.
Nomakunjalo, indlela yokubulala amaqhiwani ekudleni ngokukukokisa kancani i-pasteurisation ayisiso isihlahla sendawo engakahlwengi engabangela bona ukudla kube namaqhiwani, ngalokho iinkambiso eziqinisekisa ukuphepha kokudla nokulawulwa kwekhwalithi ziqakathekile bona zilandelwe ngesikhathi leso sokuprosesiwa kweenthako ezihlaza.
Ngabo-1800s, ibisi elikiqizwe ziinlwane ezigulako eendaweni ezingakahlwengeki lalibanga ukuhlongakala kwabantu abamakhulukhulu. Ngaleso sikhathi, abalimi babona ukuthi ukulapha ngokukokisa ibisi eliphiwa amakonyana kwehlisa ubulwelwe be-tuberculosis emhlambini wefuyo.
Khuyini i-Pasteurisation
I-Pasteurisation kukokiswa kwamanzi nokudla emazingeni womtjhiso angatjhisi khulu ahlangana ne-(60 - 100°C) imizuzu embalwa ngaphambili kobana kupholiswe msinya. I-Pasteurisation ibulala ama-enzayimu angafunekiko kunye nama-micro-organisms abangela amalwelwe afana ne-Salmonella, Listeria, Escherichia coli O157:H7 kunye ne-Staphylococcus aureus.
Indlela Yokwenza i-Pasteurisation
Amazinga womtjhiso kunye nesikhathi sendlela yokwenza i-pasteurisation zithembele emhlobeni wokudla kunye nendlela ekupakwe ngayo. Ukudla oku-pasteurised kufaka hlangana imikhiqizo yederi, amaqanda, ijuzi yeenthelo, i-cider nebeer, iwayini ye-Kosher, amandongomani, ipuphu yekoroyi kunye neliju.
Eminye imikhiqizo efana namajuzi kunye newayini zidinga i-de-aeration, besekuthi ibisi lidinge i-homogenisation ngaphambili kobana zibe-pasteurised.
Indlela yokwenza i-pasteurisation ifaka phakathi ukukokisa ibisi ku-72°C imizuzu eyi-15 kodwana ingadluli imizuzu eyi-25. Ibiseli libese lipholiswa msinya kufikela ngaphasi kuka-3°C bese liyapakwa. Iinsetjenziswa ezisetjenziswa ukukokisa nokupholisa ibisi zibizwa nge-‘heat exchanger’. I-pasteurisation ibuye ibizwe nge-‘High-Temperature Short Time’ (HTST) process.
I-Homogenisation
Indlela yokwenza lena esikhathini esinengi ilandela i-pasteurisation yebisi. Kuyindlela yokwenza esebenzisa igandeleleko eliphezulu erhelebha ukusabalalisa ngokulingana ama-fat molecules ebisini begodu ayenzi igwebu phezulu. I-homogenisation ayidingi umtjhiso.
I-Microwave Pasteurisation
Amametheriyali wokudla okuqinileko afana namaqanda angaba-pasteurised ngendlela yokwenza ebizwa nge-microwave pasteurisation. Isikhathi se-pasteurisation sokubulala i-E. coli kunye ne-Staphylococcus aureus singaba mizuzuzu eyi-30, besekuthi ukubulala i-Bacillus cereus kudinga imizuzu eyi-90.
Indlela yokwenza i-pasteurisation emakhaza ifaka ukulatjhwa kwemikhiqizo efana noburotho, ngama-microwaves, isebenzisa i-pulsed power ye-radio frequencies eku-microwave spectrum. Ibulala ama-spores abangela ukukhula kokubola eburothweni begodu ngalendlela, ingasusa ukubola eburothweni amalanga angafika ku-60.
Ama-microwave asetjenziswa emakhaya akukafaneli kuthenjelwe kiwo, ekobaneni angabulala amagciwani.
I-Cold Pasteurisation
Indlela yokwenza ye-cold pasteurisation ifakahlangana i-High-Pressure Processing (HPP), Pulsed Electric Fields (PEF) ne-ultrasound kunye ne-membrane technology.
Ngesikhathi se-high-pressure processing, imikhiqizo evaliweko (engemaphaketheni esele ilungele ukuthengiswa) ipakwa esimumathini esingaba nobudisi abungaba yi-6 000 bar. Lokhu kuvuselela ama-micro-organisms begodu kungezelela isikhathi sokobana umkhiqizo ungaboli msinya. Imikhiqizo eyenziwa ngendlela yokwenza ye-HPP ifakahlangana ukudla okuphekelwe futhi, ukudla kweenlwane zekhaya, i-salsa, i-guacamole ama-dips kunye namajuzi, ideri nemikhiqizo yeenthoro.
I-PEF ibulala ama-micro-organisms (ngokuba nomthelela ku-cell membrane) ngaphandle kokuba nomthelela omkhulu embaleni womkhiqizo, emnambithekweni kunye nakuzakhamzimba. I-PEF ayirhoni ukuvuselela amaqhiwani wama-spores ngobunengi, ngalokho akafaneli ithekniki ye-sterilisation.
I-Ultrasound pasteurisation isetjenziswa njengendlela yokususa amaqhiwani wokudla kunye nesisetjenziswa seenhlahla zokulapha begodu ingasetjenziswa ne-thermal pasteurisation yebisi, ibhiya kunye nemikhiqizo yamanzi wamaqanda.
Okhunye ukudla okuqinileko kuba-pasteurised nge-irradiation namathosi amancani we-gramma rays, ama-X-rays kunye nama-electrons ukulawula ama-foodborne pathogens.
I-Pasteurisation vs UHT
Esikhathini esinengi, amalebula wamapaka wokudla atlolwe-‘pasteurise’ nofana ‘UHT’- okuligama elifitjhani le-’Ultra High Temperature’. Khuyini umehluko hlangana ne-pasteurisation nanyana i-UHT?
I-Pasteurisation itjhisa umkhiqizo kufikela ku-71℃ imizuzu eyi-15 ngaphambili kobana ipholiswe ku-3℃.
I-UHT izokutjhisa umkhiqizo kufikela ku-137℃ imizuzu emibili ngaphambili kobana upholiswe.
Zombili iindlela zokwenza lezi zisetjenziselwa ukubulala ama-organisms abolisako.
Iinzuzo ye-Pasteurisation
I-Pasteurisation ivikela ukusilaphazeka kokudla emafektrini eprosesa ukudla bekwenze nokobona ukudla kungaboli msinya. Noma kunjalo, indlela yokwenza yokutjhisa ye-pasteurisation itjhugulula izakhamzimba ezimumethwe mkhiqizo njengombana ibulala ama-enzayimu kunye namanye amavithamini bekutjhugulule nezakhamzimba ezithileko iwenze angadleki lula.
Translated by Busisiwe Skhosana