jars of truffled turkeys

"The landlord of the Bell - whose magnificent porcelain jars of truffled turkeys are exported to the uttermost ends of the earth -..."

Lost Illusions, p. 623 (Modern Library)

The novel is set in 1822. What might sealed, shipped meat have been like at that time?

The internet leads me to this supposed Rossini quote:

"I have wept three times in my life. Once when my first opera failed. Once again, the first time I heard Paganini play the violin. And once when a truffled turkey fell overboard at a boating picnic."

Would it kill someone to put a citation on this? Anyway, I would not mind a porcelain jar of truffled turkey for Christmas.