So, I’m going to take a stab. I want to emphasize that this is a rough draft, and I hope anyone reading this who may know more or add another piece to this puzzle will do so in the comments.
[The picture is just for show — it is none of the above, just really great steak that we were sold by “El Mike,” our butcher — and grilled up for a 4th of July Barbeque.]
There is a lot of confusion in the traditional vocabulary for cooking in Mexico. The first place I tasted tasajo and cecina were in the smoky grill-room in the downtown market in Oaxaca City. There, the distinction was clear: tasajo, dried beef. Cecina was a chilied pork. (Watch yourself ordering a “michelada” there as well — it’s tomato juice and beer — not lime, salt, and beer like elsewhere in Mexico.)
Funny, I actually asked the Maria Guadalupe, one of the owners of the Munoz family workshop in Yecapixlta about the difference between tasajo and cecina. She sort of hemmed and hawed, and then said, “Well, Cecina is from here, and they make tasajo somewhere else.”
Since there is some geographical confusion, I guess a start would be to place these dishes:
-Carne Seca is claimed by Chihuahua
-Machaca by Sonora
-Cecina by Yecapixtla, Morelos and
-Tasajo by Oaxaca
The next source of misunderstanding is in the terminology. The man pictured in the post about Yecapixtla is making cecina, but his job title is “tasajero.” Tasajear as a verb means to slice up, cut in thin layers. Moving on, Carne seca is by its nature a generic term, and many of the recipes I came across call for “Tasajo (carne seca),” as well as calling machaca a type of carne seca.
Machaca, comes from the verb machacar - to pound, beat, another action that is used in making cecina, where the beef is pounded flat. Machaca is a shredded jerked beef. I’ve never eaten machaca or carne seca (I’ll be on keen lookout, though), but both are dehydrated beef cuts, that are ground or shredded.
The division seems to fall between cecina and all others. From the recipes that I’ve come across, tasajo, carne seca, and machaca all need to be rehydrated before eaten — machaca by being prepared in a kind of chili meal. Cecina, on the other hand, has retained enough water that it can be served without reconstituting.
Reading about the preparation for tasajo, it looks like the meat dries for days. I’ll write that second cecina post soon, but briefly, the meat doesn’t stay in the sun for much more than several hours, depending on the time of day. It is laid out afterwards, but not for very long. In the Munoz workshop, they also stressed that it was important not to over-salt the cecina.
For real taxidermic differentiation, I think you could you could look at drying time, salt content, the amount of water that the meat retains, and how long it could remain without refrigeration. Roughly - cecina would have more water, less salt, and shorter drying time. The others would be both drier and less perishable.
On of the most interesting sites I’ve come across is this — not about Mexican meat preparation, but Brazilian. It’s about two types: charque, which seems to fall in the tasajo camp, and carne-de-sol, which seems to be a lot like Cecina.
Reading this also makes me think that since this technique is so well spread over Latin America, Yecapixtla’s claims to have been a deer-cecina center under the Aztecs may be a bit exaggerated — maybe they were a center for butchering deer meat, sure, but the cecina technique looks more likely to have been a European import.
By chance, this afternoon I ate dinner with a guest from Mexicali. She said that machaca was popular there — in burritos, even just grabbed and eaten in dry handfuls. She also said in Southern Baja she’s had it made from ram meat, manta ray, and lobster.