Kashrut
Among the numerous laws that form "kashrut" are prohibitions on the consumption of certain animals (such as pork and shellfish), mixtures of meat and milk, and the commandment to slaughter mammals and birds according to a process known as "shechita". There are also laws regarding agricultural produce that might impact the suitability of food for consumption.
History of seafood
The Israelites ate a variety of fresh and saltwater fish, according to both archaeological and textual evidence. Remains of freshwater fish from the Yarkon and Jordan rivers and the Sea of Galilee have been found in excavations, and include St. Peter’s fish and mouthbreeders. Saltwater fish discovered in excavations include sea bream, grouper, meager and gray mullet. Most of these come from the Mediterranean, but in the later Iron Age period, some are from the Red Sea. Fishermen supplied fish to inland communities, as remains of fish, including bones and scales, have been discovered at many inland sites. To preserve them for transport, the fish were first smoked or dried and salted. Merchants also imported fish, sometimes from as far as from Egypt, where pickled roe was an export article. Remains of Nile Perch from Egypt have been found, and these must have been smoked or dried, before being imported through the trade network that connected ancient Near Eastern societies. Merchants shipped fish to Jerusalem and there was evidently a significant trade in fish; one of the gates of Jerusalem was called the Fish Gate, named for a fish market nearby. Fish products were salted and dried and sent great distances during the Israelite and Judean monarchies. However, even in the later Persian, Greek and Roman periods, the cost of preserving and transporting fish must have meant that only wealthier inhabitants of the highland towns and cities could afford it, or those who lived close to the sources, where it was less expensive.