WHAT IS KOSHER ?

Kosher in General.
The term kosher means "clean, fit or proper". The purpose of these rituals was to assure safe and sanitary meats during Biblical times. These rituals were so effective and highly regarded that they are still followed today, thousands of years later. The exacting attention to preparation and unmatched flavor explains why over two thirds of all kosher products are bought for their superior quality and excellent taste, not just for religious reasons.

Why do people observe kashrut By Rabbi David J. Fine of Temple Israel, Ridgewood NJ.
Many explanations have been offered over the millennia that seek to explain, and either encourage or discourage, the observance of the Jewish dietary laws.
The most famous, that it is good for our health, traces its pedigree back to Maimonides.  Lover of Maimonides that I am, this explanation simply does not hold water.
I know of many people who do not keep kosher and yet lead quite healthy lives. In fact, I wonder if there has ever been a kosher-keeping Olympian. (Occasionally there are Jews, but kosher?)  And conversely, every kosher butcher carries congealed chicken fat (good old schmaltz).  Need I say more?

For me, the observance of kashrut offers us an opportunity to make Judaism a part of our every moment, for what is more basic to living than the search for food to satisfy hunger? The details of the laws of kashrut are less significant, philosophically, than the fact that there are details. We are given a code whereby we control whatever goes into our mouths. (If only it would be as easy to control what comes out of our mouths!) Kashrut gives us the means to add holiness into our lives, to keep the eternal in mind, even as we take care of the most mundane.

Swordfish. By Rabbi David J. Fine of Temple Israel, Ridgewood NJ.
Standard Orthodox practice considers swordfish a non-kosher fish because it does not have scales.  However, the Law Committee, in another paper by Rabbi Isaac Klein, permits swordfish. While it is true that an adult swordfish does not have scales, it does have scales before it reaches adulthood.
Even though non-matured swordfish are generally thrown back in the sea, the fish itself is taxonomically classified as a scaled-fish, much like human beings are indeed "haired mammals" even though many mature males have lost their head of hair.

When the Deli is Open on Shabbat. By Rabbi David J. Fine of Temple Israel, Ridgewood NJ.
One area where the Conservative approach differs from the standard Orthodox approach is in regard to certification of establishments that are open on Shabbat.
Our Committee on Jewish Law and Standards does approve of a rabbi giving supervision to such an establishment, while in the Orthodox world an establishment open on Shabbat is very often dismissed as not kosher. (Soon after coming to Temple Israel I was asked by someone - not from our congregation--if I was "aware" that a certain deli nearby was "not kosher." Whether the concern in the Orthodox world is the trust of the proprietor, or the use of rabbinic power to enforce Sabbath observance, the Law Committee concluded that at times businesses are driven by the market, and the decision to operate on Shabbat may be deemed necessary by the owners, and that that does not necessarily mean that the food is not kosher if the owner is otherwise to be trusted. There is in fact a concern with food on Saturday night, since food cooked by a Jew on Shabbat is forbidden. Any other day, there is no direct connection between Sabbath desecration and kashrut. The general principle that we would apply is that when someone says that his or her food is kosher, we can assume that they are telling the truth unless we suspect that he or she is not.

Kosher Meat
For meat to be kosher you must start at the very beginning. That means, only healthy animals can be slaughtered for use in kosher foods. These animals must have split hooves and chew their cud. Cattle and sheep are the primary animals used in the koshering process. In the USA, only the front quarters of the animal are used for koshering.

Hogs and pigs do not chew their cuds and are therefore not Kosher.

A kosher inspection starts while the animals are still alive and continues until the finished product leaves the plant. This system operates under the diligent and watchful supervision of kosher inspectors, who stringently control the process from the time the meat is slaughtered until it is shipped.

Kosher Slaughter (Shechitah)
This is the first component of additional costs. The slaughter is performed by a "shochet"
(a man of skill, piety and expertise).

1. Neck area is clean
2. Severing of the trachea and esophagus
3. Cut is within the proper area
4. No hesitation
5. No pressing
6. No tearing

Examination (B'dikah)
This is the second increase in costs and the first upgrade in quality. After the slaughter, the internal organs and especially the lungs are searched inside the animal to assure the animal was healthy and did not have any injuries or diseases. After the lungs are removed from the animal, a second examination is made to make sure the lungs have no adhesions or other defects. If the adhesions can be peeled away without perforating the lung, and everything else has passed, the animal is accepted as kosher killed.

For every animal passed by the USDA (Department of Agriculture) as fit for consumption, only a little more than half are accepted for kosher.

Glatt
Glatt is a Yiddish term that means perfectly smooth and is used to refer to animals who's lungs are free of any blemish or adhesion. Glatt is viewed by many people as a higher form of kosher. Meat that has passed inspection, whether Glatt or not, is accepted as kosher killed.

Glatt and Hebrew National. By Rabbi David J. Fine of Temple Israel, Ridgewood NJ. 
"Glatt kosher" refers to an overly strict practice of the kosher slaughterer discarding all animals with any lung deficiencies rather than investigating whether or not the lung passes for kosher. The halakhic literature devotes significant space to the slaughterer's duty to determine what type of lung is kosher and what is not. Rather than raise the price of kosher meat and discard centuries old traditions of kosher slaughterers, I find it preferable to buy non-glatt meat, like Hebrew National, whenever I can find it.

Washing
All kosher killed meat must be either kosher made (soaked and salted, or broiled) or washed
within 72 hours of the slaughter.

Kosher Made
The meat is soaked in water for at least 30 minutes to prepare it for the salting process.
The soaked meat is salted (under rabbinical supervision) by specially trained men. The salt used is kosher salt that has been approved by our rabbis for this process. After salting, the meat is left for one hour with the salt on it and allowed to drain. At the end of 60 minutes, the meat is washed to remove the salt, and the meat is now considered kosher.

Nikur/Traboring
This is the sixth increase in cost and the fourth upgrade in quality. These terms mean to dig out and refers to the requirement for the removal of veins, blood clots, arteries, and forbidden fats.
This process is performed by specially trained men called minikurs. The trimmings that are removed during traboring are not used in kosher product, but are sold off to non-kosher meat plants.

Link to Articles By Rabbi David J. Fine:
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