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פסחים קטז, א
שֶׁבְּכָל הַלֵּילוֹת אָנוּ אוֹכְלִין בָּשָׂר צָלִי שָׁלוּק וּמְבוּשָּׁל, הַלַּיְלָה הַזֶּה — כּוּלּוֹ צָלִי…
On all other nights we may eat meat that has been roasted or stewed or cooked. But on this night, we may only eat the meat [of the Passover offering] that has been roasted
Spring is just around the corner (unless you are reading this in the southern hemisphere, in which case, please ignore) and barbecue grills are soon going to be fired up. The kobran Pesach, the Pashal lamb that was offered in the Spring festival of Passover needed a barbecue of its own. It had to be cooked over an open fire, as the Mishnah on this page of Talmud reminds us. Earlier in this tractate the Mishnah went into other meticulous details about the permitted cooking process:
פסחים עד, א
מַתְנִי׳ כֵּיצַד צוֹלִין אֶת הַפֶּסַח? מְבִיאִין שַׁפּוּד שֶׁל רִמּוֹן, וְתוֹחֲבוֹ לְתוֹךְ פִּיו עַד בֵּית נְקוּבָתוֹ, וְנוֹתֵן אֶת כְּרָעָיו וְאֶת בְּנֵי מֵעָיו לְתוֹכוֹ, דִּבְרֵי רַבִּי יוֹסֵי הַגְּלִילִי. רַבִּי עֲקִיבָא אוֹמֵר: כְּמִין בִּישּׁוּל הוּא זֶה, אֶלָּא תּוֹלִין חוּצָה לוֹ. אֵין צוֹלִין אֶת הַפֶּסַח לֹא עַל הַשַּׁפּוּד וְלֹא עַל הָאַסְכָּלָא. אָמַר רַבִּי צָדוֹק: מַעֲשֶׂה בְּרַבָּן גַּמְלִיאֵל שֶׁאָמַר לְטָבִי עַבְדּוֹ: צֵא וּצְלֵה לָנוּ אֶת הַפֶּסַח עַל הָאַסְכָּלָא
MISHNA: How does one roast the Paschal lamb? One brings a spit [shappud] of pomegranate wood and thrusts it into the mouth of the lamb until it reaches its anus, and one then puts its legs and entrails inside it and roasts it all together; this is the statement of Rabbi Yosei HaGelili…
One may not roast the Paschal lamb on the metal spit nor on a metal grill [askela]…
The reason that a wooden spit had to be used is that a metal spit would conduct heat to the inside of the carcass and cook it, “and in the Torah it states that the Paschal lamb must be roasted in fire and not roasted through something else [like the heat conducted along a metal spit] (וְרַחֲמָנָא אָמַר ״צְלִי אֵשׁ״, וְלֹא צָלִי מֵחֲמַת דָּבָר אַחֵר). So today on Talmudology we ask: “what is so special about the roasting process?”
Roasting and the Maillard Reaction
In 1912 the French biochemist Louis Camille Maillard described a special reaction that occurs only when food has reached a temperature of 280-330F, (140-165C) and if your French is good enough you can read his original description here. What occurs in this special temperature range is that amino acids found in proteins (like meat and fish) react with reducing sugars giving the food its characteristic brown color and special flavor. Maillard uncovered a complex family of reactions, and as noted in Stuart Farrimond’s excellent book The Science of Cooking, these reactions “help us make sense of the many ways in which food browns and takes on flavor as it cooks.” He continues (p 16):
Seared steak, crispy fish skin, the aromatic crust of bread, and even the aroma of toasted nuts and spices are all thanks to this reaction…Understanding the Maillard reaction helps the cook in many ways: adding fructose-fish honey to a marinade fuels the reaction; pouring cream into simmering sugar provides milk proteins and sugars for the butterscotch and caramel flavors; and brushing pastry with egg provides extra protein for the crust to brown.
As Farrimond the food scientist explains, the temperature needs to reach at least 284F (140C) to give the amino acids and sugars enough energy to react together. At this temperature the proteins and sugars fuse, releasing “hundreds of new flavors and aromatic substances” and the food starts to turn brown. At around 320F (160C) “molecular changes continue and more enticing new flavors and aromas are created…there are now cascades of malty, nutty, meaty and caramel-like flavors.” Now is the time to be careful and pay attention to the temperature, for above about 356F ( 180C) the food begins to char. This destroys the aromas and leaves acrid, bitter flavors. So “watch the food closely and remove it from the heat before it begins to blacken.”
None of this happens when you boil food, because the boiling point of water (at sea level) is 212F (100C) so the all these glorious mouth watering reactions cannot occur.
Let’s pause to think about how some of the other biblical sacrifices were offered, and whether they too underwent the Maillard reaction.
The Burnt Offering (קרבן עולה)
During the Temple period there were other animal sacrifices that were roasted over a flame. One of these was called the Korban Oleh (lit. the sacrifice that goes up), but things didn’t stop with the Maillard process. This sacrifice had to be entirely burned on the altar, (although the skin was saved and given to the Priestly family on rotation that day). Nothing was left of it but charcoal and ashes, which were then shoveled out and disposed of in a ritual of its own. This was a popular sacrifice, which was offered for all sorts of reasons: like recovery from a skin disease, the new appointment of a priest, the completion of a Nazirite's vow, after recovery from skin disease, by a woman after childbirth, after recovery from a state of abnormal bodily discharges, conversion into Judaism or as a voluntary sacrifice, when the sacrificial animal could be a young bull, ram, year-old goat, turtle doves, or pigeons.
The Sin offering (קרבן חטאת) and the Guilt offering (קרבן אשם)
Much of the sin offering (the kidneys, their fat, the entrails and part of the liver) was burned on the altar. Sometimes the entire carcass was burned to a crisp, and sometimes it was left for the priests - the Cohanim - who could eat it under certain conditions (Lev. 6:25-30). Most of these rules also applied to the guilt offering.
The Tamid Offering (קרבן תמיד)
This was offered twice a day, every day including Shabbat. It was also brought on the New Moon (Rosh Chodesh) and on Pesach and Sukkot. Most of it was burned on the altar.
The “Peace’ Offering (קרבן שלם)
This was a large category of offerings, some for festivals, some by the Nazarite completing his or her term, and some for just saying thanks. Many had to be brought with bread, and much of the animal was burned, though male Cohanim were entitled to eat some parts that remained.
רמבם הל׳ מעשה קרבנות 9:6
וְכֵיצַד מַעֲשֵׂה שְׁלָשְׁתָּן. שׁוֹחֵט וְזוֹרֵק הַדָּם כְּמוֹ שֶׁבֵּאַרְנוּ. וּמַפְשִׁיט וּמוֹצִיא הָאֵימוּרִין. וְאַחַר כָּךְ מְנַתֵּחַ אֶת הַבָּשָׂר וּמַפְרִישׁ הֶחָזֶה וְשׁוֹק הַיָּמִין וְנוֹתֵן הָאֵימוּרִין עִם הֶחָזֶה וְהַשּׁוֹק עַל יְדֵי הַבְּעָלִים וְכֹהֵן מַנִּיחַ יָדוֹ תַּחַת יְדֵי הַבְּעָלִים וּמֵנִיף הַכּל לִפְנֵי ה' בַּמִּזְרָח. וְכֵן כָּל הַטָּעוּן תְּנוּפָה בַּמִּזְרָח מְנִיפִין אוֹתוֹ
What is procedure for bringing these three [types of peace offerings]? [The sacrificial animals] should be slaughtered and their blood should be sprinkled on the altar, as we explained.They are skinned and the portions offered on the altar are removed. Afterwards, the meat is cut up and the breast and the right thigh are set aside. The portions to be offered together with the breast and the thigh are placed on the hands of the owners…
How the Korban Pesach differed
Compared with nearly every other animal scarified in the Temple in Jerusalem, the Passover offering was the only one to be eaten in full by the participants (though the usual bits were offered up on the altar). In fact one of it requirements was that it be eaten entirely. Noting was left over. It was eaten in small family units and everyone had to have at least a little bit. These small groups ensured that everyone would smell and taste the barbecued lamb. Its aroma and taste were very special, for they were the result of the Maillard reaction. No doubt the memory of it all lingered for a long time afterwards, and just as the memory began to fade, it was time to do it all over again.
