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The Surprising Journey of Making Zinc Rain Gutters and Ham | How It's Made | Science Channel

Hören/Video/Science Channel/The Surprising Journey of Making Zinc Rain Gutters and Ham | How It's Made | Science Channel

The Surprising Journey of Making Zinc Rain Gutters and Ham | How It's Made | Science Channel

Science Channel
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Untertitel (115)

0:00Zinc gutters drain rainwater and in the process develop a natural resistance to
0:05corrosion. When zinc is exposed to wet and dry cycles, a chemical reaction occurs,
0:12forming a protective patina on its surface.
0:15No paint or special treatment needed.
0:18You can't stop the rain, but you can stop it from damaging buildings and their
0:23foundations. These U shaped zinc gutters funnel water away from the structures to keep
0:28them dry. The process starts with the production of these 46 ton coils of zinc.
0:36The zinc arrives at the factory in the form of thick plates.
0:40These plates are almost 100% zinc.
0:46The plates drop into a furnace.
0:48Inside, the temperature reaches 750°F.
0:52Workers add a bit of copper and titanium to reinforce the zinc, and it melts into a
0:58homogeneous liquid.
1:01The molten zinc then flows into a trough style conveyor system.
1:07Residues like ashes float to the top of the metal soup, and a worker skims them off.
1:15A floating puck monitors the speed and depth of the zinc blende to prevent overflow.
1:23The molten zinc now arrives at the casting machine.
1:27Here, three foot wide steel unwinds and once linear, the zinc flows onto it.
1:34The steel acts as a mould to form the zinc into a long rigid sheet.
1:41Water flows onto the zinc to accelerate cooling and solidification.
1:46Since water and liquid zinc don't mix, the water simply runs off the surface.
1:53Now solid, the zinc plate is almost a third of an inch thick, far too thick for making
2:00lightweight rain gutters.
2:02The next operation will thin the plate down dramatically.
2:07This is a powerful rolling mill.
2:09The pressure on its rollers is so great that they often must be replaced.
2:16Once the new rollers have been loaded, the mill heats them up.
2:21The operator activates the rollers as they revolve.
2:25The hot rollers exert 770 tons of pressure to iron the zinc much thinner.
2:33Meanwhile, just ahead, a steel belt tensioning system swings into action.
2:39This system prevents slackening in the zinc sheet as it exits the rolling mill and moves
2:44forward. You can see the difference the rolling has made.
2:48It has reduced the thickness of the zinc sheet to about three quarters of a
2:53millimeter. The steel belt system maintains the tension in the zinc sheet as it's wound
3:00around a core.
3:01This produces the 46 ton coil of zinc.
3:05It's known as the mother coil.
3:08Approximately 25 miles of rain gutters can be made from this coil.
3:14Workers slit the mother coil into three.
3:17Each coil is a foot wide.
3:20It is now the correct width to be formed into rain gutters.
3:26A crane lifts one of the narrower coils over the factory floor.
3:30Its journey is guided by the operator below.
3:35This puts it in position to be mounted to the next machine, one that will cut it into
3:40uniform 13 foot long strips.
3:43That's the standard length for the rain gutters.
3:47As the zinc uncoils, an overhead mirror provides a top view for the operator.
3:55In quick swoops.
3:56The blade slices the zinc sheeting to the correct length.
4:02The zinc strips then travel through a progressively narrow channel and over a
4:07cylinder. This rounds the profile.
4:12More rollers, improve on the U-shape and also curl the edges of the gutters to
4:17reinforce them.
4:21This gives the zinc rain gutters their final shape.
4:26The automated profiler ejects the 13 foot long gutters onto a rounded rack.
4:31Then it tips to stack the gutters neatly on top of each other.
4:37The zinc rain gutters are ready to hang.
4:40On site, they'll be welded together and attach to the roof with special hooks.
4:47They should come in handy on a rainy day.
4:50The French Basque Country is culturally quite distinct from the rest of France.
4:55Located in the southwest bordering Spain, the region is known, among other things, for
5:00its ham, which is salted and air cured in an old tradition passed down through generations
5:06of Basque farmers.
5:08There are several types of traditional Basque ham.
5:11This one, called quinoa, is marbled with fat and has a deep, strong, fruity flavor.
5:18Its distinct taste and composition begin with a specific breed of pig.
5:23The Basque Country piebald refers to the animal's skin.
5:28This pig breed is native to the Basque region, where livestock are raised on small
5:33farms in the valleys of the Pyrenees mountains.
5:38Unlike commercially farmed animals, the female pigs have small litters of 6 to 9
5:43piglets which grow up roaming and grazing along the vast mountainsides.
5:49On an average of two acres of land per 30 piglets.
5:53As a result of this free range rearing, the pigs grow more slowly and become heavier than
5:58commercially farmed pigs.
6:02Once the animals reach a weight of about £330, which usually takes a year to 15
6:08months, they go to the slaughterhouse.
6:12Each carcass is stamped with an identification number.
6:16Traditional ham is made from the hind legs.
6:21After tagging the leg, a worker places it in a machine which brands the canto a symbol
6:27into the flesh.
6:32Then another worker spreads dry salt on the exposed portion.
6:36The salt comes from Sayda debayan, a saltwater spring in a basin bordered by the
6:42Pyrenees Mountains.
6:43Theodora River and the Atlantic Ocean.
6:49Workers leave the salted ham in a cold, damp room for one day per every £2, typically
6:55about 15 days per ham.
6:58The salt preserves the meat.
7:00Next, the ham undergoes a first dry curing.
7:05It hangs on a stainless steel rack in a temperature and humidity controlled room for
7:09seven months.
7:14When the ham comes out of the room, it has lost about 20% of its original weight because
7:19most of the moisture has evaporated.
7:24A worker brushes off the surface.
7:30And coats the exposed part of the ham with a special grease that's made out of pigs
7:35kidneys, rice flour and water.
7:42This grease prevents the surface from drying out and crusting during the second dry
7:47curing. The ham now goes into a second drying room, which dries the ham in the open
7:55air. Taking advantage of this particular geographic location, a warm southern wind
8:01from Spain and humid air from the Atlantic Ocean to the west blow into the room through
8:07windows. Nature does all the work.
8:11Humans merely regulate the airflow and humidity by lifting or lowering the blinds.
8:18In this room, the ham hangs from a wooden rather than stainless steel rack.
8:23That's because the wood absorbs excess humidity and transfers moisture to the meat
8:28if the air gets too dry.
8:32As the ham dries, its flavor concentrates the Charcutier, an artisanal pork butcher,
8:39inspects every ham carefully.
8:46The wind that dries.
8:47The ham carries pollen and other natural particles, which give this ham a distinct
8:52flavor and fragrance.
8:56The secret is slow curing until the ham reaches optimal maturity.
9:01That takes approximately one month per £2, so the ham remains in the second drying room
9:07for more than a year.
9:10When the cured ham is ready, workers sprinkle it with espelette pepper, a mildly
9:15hot pepper from the northern Basque Country.
9:19This gives the ham a fragrance that's as appetizing as its taste.