Questions:
Not a category until just before the modern period - falls out into a variety of different categories.
Biblically, combined with other laws that seem to have nothing to do with food.
Some focus on species
"Boiling kid in mother's milk" x3
Sciatic nerve
Blood, organ fat
Sacrificial system
(ג) אִ֥ישׁ אִישׁ֙ מִבֵּ֣ית יִשְׂרָאֵ֔ל אֲשֶׁ֨ר יִשְׁחַ֜ט שׁ֥וֹר אוֹ־כֶ֛שֶׂב אוֹ־עֵ֖ז בַּֽמַּחֲנֶ֑ה א֚וֹ אֲשֶׁ֣ר יִשְׁחַ֔ט מִח֖וּץ לַֽמַּחֲנֶֽה׃ (ד) וְאֶל־פֶּ֜תַח אֹ֣הֶל מוֹעֵד֮ לֹ֣א הֱבִיאוֹ֒ לְהַקְרִ֤יב קָרְבָּן֙ לַֽה' לִפְנֵ֖י מִשְׁכַּ֣ן ה' דָּ֣ם יֵחָשֵׁ֞ב לָאִ֤ישׁ הַהוּא֙ דָּ֣ם שָׁפָ֔ךְ וְנִכְרַ֛ת הָאִ֥ישׁ הַה֖וּא מִקֶּ֥רֶב עַמּֽוֹ׃ (ה) לְמַעַן֩ אֲשֶׁ֨ר יָבִ֜יאוּ בְּנֵ֣י יִשְׂרָאֵ֗ל אֶֽת־זִבְחֵיהֶם֮ אֲשֶׁ֣ר הֵ֣ם זֹבְחִים֮ עַל־פְּנֵ֣י הַשָּׂדֶה֒ וֶֽהֱבִיאֻ֣ם לַֽה' אֶל־פֶּ֛תַח אֹ֥הֶל מוֹעֵ֖ד אֶל־הַכֹּהֵ֑ן וְזָ֨בְח֜וּ זִבְחֵ֧י שְׁלָמִ֛ים לַֽה' אוֹתָֽם׃ (ו) וְזָרַ֨ק הַכֹּהֵ֤ן אֶת־הַדָּם֙ עַל־מִזְבַּ֣ח ה' פֶּ֖תַח אֹ֣הֶל מוֹעֵ֑ד וְהִקְטִ֣יר הַחֵ֔לֶב לְרֵ֥יחַ נִיחֹ֖חַ לַה'
(3) if anyone of the house of Israel slaughters an ox or sheep or goat in the camp, or does so outside the camp, (4) and does not bring it to the entrance of the Tent of Meeting to present it as an offering to the LORD, before the LORD’s Tabernacle, bloodguilt shall be imputed to that man: he has shed blood; that man shall be cut off from among his people. (5) This is in order that the Israelites may bring the sacrifices which they have been making in the open—that they may bring them before the LORD, to the priest, at the entrance of the Tent of Meeting, and offer them as sacrifices of well-being to the LORD; (6) that the priest may dash the blood against the altar of the LORD at the entrance of the Tent of Meeting, and turn the fat into smoke as a pleasing odor to the LORD;
(יג) הִשָּׁ֣מֶר לְךָ֔ פֶּֽן־תַּעֲלֶ֖ה עֹלֹתֶ֑יךָ בְּכָל־מָק֖וֹם אֲשֶׁ֥ר תִּרְאֶֽה׃ (יד) כִּ֣י אִם־בַּמָּק֞וֹם אֲשֶׁר־יִבְחַ֤ר ה' בְּאַחַ֣ד שְׁבָטֶ֔יךָ שָׁ֖ם תַּעֲלֶ֣ה עֹלֹתֶ֑יךָ וְשָׁ֣ם תַּעֲשֶׂ֔ה כֹּ֛ל אֲשֶׁ֥ר אָנֹכִ֖י מְצַוֶּֽךָּ׃ (טו) רַק֩ בְּכָל־אַוַּ֨ת נַפְשְׁךָ֜ תִּזְבַּ֣ח ׀ וְאָכַלְתָּ֣ בָשָׂ֗ר כְּבִרְכַּ֨ת ה' אֱלֹקֶ֛יךָ אֲשֶׁ֥ר נָֽתַן־לְךָ֖ בְּכָל־שְׁעָרֶ֑יךָ הַטָּמֵ֤א וְהַטָּהוֹר֙ יֹאכְלֶ֔נּוּ כַּצְּבִ֖י וְכָאַיָּֽל׃ (טז) רַ֥ק הַדָּ֖ם לֹ֣א תֹאכֵ֑לוּ עַל־הָאָ֥רֶץ תִּשְׁפְּכֶ֖נּוּ כַּמָּֽיִם׃
(13) Take care not to sacrifice your burnt offerings in any place you like, (14) but only in the place that the LORD will choose in one of your tribal territories. There you shall sacrifice your burnt offerings and there you shall observe all that I enjoin upon you. (15) But whenever you desire, you may slaughter and eat meat in any of your settlements, according to the blessing that the LORD your God has granted you. The unclean and the clean alike may partake of it, as of the gazelle and the deer. (16) But you must not partake of the blood; you shall pour it out on the ground like water.
(יא) כִּ֣י נֶ֣פֶשׁ הַבָּשָׂר֮ בַּדָּ֣ם הִוא֒ וַאֲנִ֞י נְתַתִּ֤יו לָכֶם֙ עַל־הַמִּזְבֵּ֔חַ לְכַפֵּ֖ר עַל־נַפְשֹׁתֵיכֶ֑ם כִּֽי־הַדָּ֥ם ה֖וּא בַּנֶּ֥פֶשׁ יְכַפֵּֽר׃ (יב) עַל־כֵּ֤ן אָמַ֙רְתִּי֙ לִבְנֵ֣י יִשְׂרָאֵ֔ל כָּל־נֶ֥פֶשׁ מִכֶּ֖ם לֹא־תֹ֣אכַל דָּ֑ם וְהַגֵּ֛ר הַגָּ֥ר בְּתוֹכְכֶ֖ם לֹא־יֹ֥אכַל דָּֽם׃ (ס) (יג) וְאִ֨ישׁ אִ֜ישׁ מִבְּנֵ֣י יִשְׂרָאֵ֗ל וּמִן־הַגֵּר֙ הַגָּ֣ר בְּתוֹכָ֔ם אֲשֶׁ֨ר יָצ֜וּד צֵ֥יד חַיָּ֛ה אוֹ־ע֖וֹף אֲשֶׁ֣ר יֵאָכֵ֑ל וְשָׁפַךְ֙ אֶת־דָּמ֔וֹ וְכִסָּ֖הוּ בֶּעָפָֽר׃ (יד) כִּֽי־נֶ֣פֶשׁ כָּל־בָּשָׂ֗ר דָּמ֣וֹ בְנַפְשׁוֹ֮ הוּא֒ וָֽאֹמַר֙ לִבְנֵ֣י יִשְׂרָאֵ֔ל דַּ֥ם כָּל־בָּשָׂ֖ר לֹ֣א תֹאכֵ֑לוּ כִּ֣י נֶ֤פֶשׁ כָּל־בָּשָׂר֙ דָּמ֣וֹ הִ֔וא כָּל־אֹכְלָ֖יו יִכָּרֵֽת׃
(11) For the life of the flesh is in the blood, and I have assigned it to you for making expiation for your lives upon the altar; it is the blood, as life, that effects expiation. (12) Therefore I say to the Israelite people: No person among you shall partake of blood, nor shall the stranger who resides among you partake of blood. (13) And if any Israelite or any stranger who resides among them hunts down an animal or a bird that may be eaten, he shall pour out its blood and cover it with earth. (14) For the life of all flesh—its blood is its life. Therefore I say to the Israelite people: You shall not partake of the blood of any flesh, for the life of all flesh is its blood. Anyone who partakes of it shall be cut off.
(טו) וְכָל־נֶ֗פֶשׁ אֲשֶׁ֨ר תֹּאכַ֤ל נְבֵלָה֙ וּטְרֵפָ֔ה בָּאֶזְרָ֖ח וּבַגֵּ֑ר וְכִבֶּ֨ס בְּגָדָ֜יו וְרָחַ֥ץ בַּמַּ֛יִם וְטָמֵ֥א עַד־הָעֶ֖רֶב וְטָהֵֽר׃
(15) Any person, whether citizen or stranger, who eats what has died or has been torn by beasts shall wash his clothes, bathe in water, and remain unclean until evening; then he shall be clean.