Yevamos 120a: One may not testify that a man is dead unless he saw him within three days of death, but if he saw him later, his appearance may have changed and the witness could mistake his identity.
Rav Dimi permitted the wife of a man who drowned in Karmi and was pulled out of the water more than three days later. Rava permitted the wife of a man who drowned in the Tigris and was pulled out onto the bridge five days later. The reason is because water tightens up the body.
The Aruch Hashulchan 69:72 says that this is proof to the rule of the Gaonim, brought in Shulchan Aruch Yoreh Deah 69:12, that one may not rely on salting to remove the blood from meat after three days, because the blood dries up inside the body (causing the face to be disfigured) and cannot be removed by the salt. Thus if the meat was soaked within the first three days, it can be salted even after three days, similar to the man who fell into the river whose blood and appearance is kept fresh by the water.
יבמות קכ ע”א: אין מעידין אלא עד ג׳ ימיםֹ. ופירש רש”י אם ראוהו בתוך ג׳ ימים למיתתו מעידין עליו אבל אם לא ראוהו עד לאחר ג׳ ימים חיישינן שמא נשתנו מראית פניו ואין זה שהם סבורים.
שם קכא ע”א: דההוא גברא דטבע בכרמי, ואסקוהו אבי הדיא לבתר תלתא יומין, ואנסבה רב דימי מנהרדעא לדביתהוֹ ותו, ההוא גברא דאטבע בדגלת ואסקוהו אגישרא דשביסתנא, ואנסבה רבא לדביתהו אפומא דשושביני לבתר חמשה יומיֹ וכו’ שאני מיא, דצמתי.
שו”ע יו”ד סט,יב: בשר ששהה ג׳ ימים מעת לעת בלא מליחה נתייבש דמו בתוכו ולא יצא עוד ע״י מליחה ואין לאכלו מבושל אלא צלי וכו’.
שם סעיף יג: ואם שרו אותו במים תוך הג׳ ימים יכול להשהותו עוד שלשה ימים אחרים פחות חצי שעה.
Rabbi Yirmiyohu Kaganoff served as a rav in Buffalo, New York. One short erev Shabbos, there was a severe blizzard across a large part of the country; the major interstate highways and all state routes were closed. About half an hour before Shabbos, the telephone rang. “Rabbi Kaganoff, I was given your phone number in case of emergency,” said the woman on the other end. “I am a dispatcher for the All-American Transport Company. We have a load of kosher meat held up by the storm that needs to be washed by Saturday night.” Rabbi Kaganoff asked her if she knew the last time the meat was washed. “It was last washed 11 p.m. Wednesday and needs re-washing by 11 p.m. Saturday.”
He politely asked if she could call him back in about 25 hours, which would still be several hours before the meat’s deadline.
Right after Shabbos, the telephone rang again. A different, unfamiliar voice identified itself as the driver of the stuck truck. His vehicle was exactly where it had been Friday afternoon, stranded not far from the main highway.
Rabbi Kaganoff said he would make some phone calls and get back to him. But he could find no mashgiach in the vicinity of Nebraska who was able to go and supervise the washing of the meat. With no good news to tell the trucker, he procrastinated on calling him back.
An hour later, the phone rang again, with the trucker on the line. “Rabbi,” he said, with obvious excitement in his voice, “I’ve solved the problem. I discovered that I was stranded a few thousand feet from a fire station. And now, all the meat has been properly hosed. Listen to this letter:
“On Saturday evening, the 22nd of January, at exactly 9:25 pm, I personally oversaw the successful washing of a kosher load of meat on trailer 186CX and tractor 2008PR. To this declaration, I do solemnly lend my signature and seal,
James P. O’Donald, Fire Chief, Lincoln Fire Station #2.”
Probably noticing Rabbi Kaganoff’s momentary hesitation, the trucker continued, “Rabbi, do I need to have this letter notarized?”
“No, I am sure that won’t be necessary,” he replied. He was not about to tell the driver that halachah requires that a Torah observant Jew supervise the washing of the meat. On the contrary, he complimented him on his diligence and his tremendous sense of responsibility.
Now it was Rabbi Kaganoff who had a responsibility on his hands: Since he knew the meat’s ultimate destination, he needed to inform the rabbi of that town of the situation so that he could reach a decision.
The rabbi of that town consulted with a posek who reasoned that since the truck had been stuck in a major blizzard, unquestionably the meat had been frozen solid, and that they could rely on this to kasher the meat after it thawed out.
Although the Pri Megadim and others do not allow extending the 3-day deadline by freezing, the Aruch Hashulchan and others disagree, and R’ Moshe Feinstein relied on it in extenuating circumstances. (Igros Moshe YD 1:27, 2:21)
[We see here that the kashrus supervisors in this meat plant allowed two leniencies: 1) They allowed extending the 3-day deadline further by washing the meat a second time – the Yad Efraim is uncertain whether this works. 2) They allowed simply hosing down the meat, as opposed to soaking it, and thus they would have relied on the fire hose if not for the fact that it was done without Jewish supervision. The Taz says it must actually be soaked, and the Yad Avraham allows rinsing only in cases when the veins in the meat were already removed. Evidently, the kashrus supervisors in this story relied on the Yad Efraim, who says that one should not be lenient and rinse the meat if it is possible to soak it, implying that if there is no other way, it may be rinsed.]