Killing and Plucking
Following stunning, the blood vessels in the animal’s neck are cut to kill the bird and to allow it to bleed out. There are many techniques and ways to perform the killing act. The main difference is between slaughtering with and without stunning, the latter being influenced by religious laws. Namely, traditional slaughterhouses forbid stunning due to religious laws (Halal or Kosher are the most well-known regulations), meaning animals are meant to die by bleeding only. In religious slaughterhouses the killing process is carried out by one or more trained professionals who use a very sharp blade to manually cut the jugular veins. Killing in traditional slaughterhouses is always a manual act bound to strict guidelines.
In abattoirs where stunning is practiced, killing can be done by hand or by using automatic equipment with backup personnel. This is mostly a matter of economics. An automatic killing machine has a single or double blade to efficiently and correctly sever the veins without damaging trachea.
After the kill cut has been made, the birds will generally lose around half of the total amount of blood in 1,5 to 2 minutes of bleeding time. The birds are conveyed over a v-shaped bleeding trough which collects the blood. Inadequate bleeding results in a product with a shorter shelf life. However letting birds bleed out too long will cause problems with plucking.
Before plucking and after the birds have bled out, the birds are conveyed through a water tank filled with hot, scalding water. Hence the name of the machine: scalder or scalding tank. The water can be heated by heating elements and functions to help loosen the feathers from the skin. This is absolutely vital to achieve a good defeathering result. Blowers inside the tank will create turbulence in the water, meaning the birds are completely immersed and scalded.
After the feathers have been loosened in the scalder, the birds are plucked one ore more defeathering machines. Cabinets with multiple rows or rotating discs with rubber plucking fingers are placed on both sides of the shackle line. One plucking machine can hold up to 32, 40 or 64 rotating discs with each disc containing 8 to 10 plucking fingers. The rubber picking fingers are designed to remove the feathers from the carcass.
The amount of plucking discs and machines needed, depend on the required capacity per hour. The end result is always a cleanly picked bird. Height and spacing of the discs can be adjusted to accommodate different bird sizes.
Baada ya kuangushwa, mishipa ya damu katika shingo ya mnyama hupasuliwa ili kuua ndege na kumruhusu kuvuja damu. Kuna mbinu na njia nyingi za kufanya tendo la kuua. Tofauti kuu ni kati ya kuchinjwa kwa kuangushwa na bila kuangushwa, huku kuangamizwa huku kukitegemea sheria za kidini. Kwa mfano, mashamba ya kuua wanyama ya kawaida hayaruhusu kuangamiza wanyama kwa sababu ya sheria za kidini (Halal au Kosher ni kanuni zinazojulikana zaidi), ikimaanisha kwamba wanyama wanapaswa kufa kwa kutokwa na damu tu. Katika mashamba ya kuua wanyama, mauaji hufanywa na mtaalamu mmoja au zaidi aliyezoezwa ambaye hutumia kisu kali sana kukata mishipa ya damu. Kuua katika mashamba ya kawaida ya kuchinjia wanyama ni kazi ya mikono ambayo hufanywa kwa kufuata kanuni kali. Katika mashamba ya kuchinjia wanyama ambapo watu hufanyiwa upigaji-moto, wanyama wanaweza kuuawa kwa mikono au kwa kutumia vifaa vya kiotomatiki na wafanyakazi wa kuunga mkono. Hii ni hasa suala la kiuchumi. Mashine ya kuua moja kwa moja ina kisu kimoja au viwili ili kukata mishipa kwa ufanisi na kwa usahihi bila kuharibu trachea. Baada ya kuuawa, ndege hupoteza nusu ya damu yao katika muda wa dakika 1.5 hadi 2. Ndege hao hupelekwa kwenye mfereji wenye umbo la herufi V ambao hukusanya damu. Mvua isiyofaa husababisha bidhaa yenye muda mfupi wa kudumu. Hata hivyo kuruhusu ndege kutokwa na damu kwa muda mrefu sana kutasababisha matatizo na kuondoa. Kabla ya kuondoa na baada ya ndege hao kutokwa na damu, wao hupelekwa kupitia tangi la maji lililojaa maji moto. Kwa hiyo jina la mashine: scalder au scalding tank. Maji yanaweza kupasha joto kwa kutumia vifaa vya kupasha joto na kazi za kusaidia kuondoa manyoya kutoka kwenye ngozi. Hii ni muhimu kabisa ili kufikia matokeo mazuri ya kushindwa. Vipuli vilivyo ndani ya tangi huunda msukosuko katika maji, ikimaanisha kwamba ndege huzikwa kabisa na kuchomwa moto. Baada ya manyoya kuwa loosened katika scalder, ndege ni plucked moja madini zaidi defeathering mashine. Kabati na safu nyingi au diski zinazozunguka na vidole vya kuvuta mpira huwekwa pande zote mbili za mstari wa shackle. Mashine moja ya kuondoa inaweza kubeba diski 32, 40, au 64 zinazozunguka, na kila diski ina vidole 8 hadi 10. Vidole vya kuchukua mpira vimetengenezwa ili kuondoa manyoya kutoka kwenye mnyama. Kiasi cha diski plucking na mashine zinahitajika, hutegemea uwezo required kwa saa. Matokeo ya mwisho sikuzote ni ndege aliyechaguliwa kwa usafi. Urefu na umbali wa diski zaweza kurekebishwa ili kukidhi ukubwa tofauti wa ndege.