179:
525:, most rendering installations used the dry process. In the 1960s, continuous dry processes were introduced, one using a variation of the conventional dry cooker and the other making use of a mincing and evaporation process to dry the material and yield the fat. In the 1980s, high energy costs popularized the various "wet" continuous processes. These processes were more energy efficient and allowed the re-use of process vapours to pre-heat or dry the materials during the process.
1364:
1373:
378:. The first stage separates the liquid water and fat mixture from the solids. The second stage further separates the fat from the water. The solids may be used in food products, pet foods, etc., depending on the original materials. The separated fat may be used in food products, or if in surplus, may be diverted to soap making operations. Most edible rendering is done by meat packing or processing companies.
77:
1389:
387:
vessel to drive off the moisture and simultaneously release the fat from the fat cells. The material is first ground, then heated to release the fat and drive off the moisture, percolated to drain off the free fat, and then more fat is pressed out of the solids, which at this stage are called "cracklings" or "dry-rendered tankage". The cracklings are further ground to make meat and
36:
1397:
1354:
1381:
395:
materials. The material is heated with added steam and then pressed to remove a water-fat mixture that is then separated into fat, water, and fine solids by stages of centrifuging and/or evaporation. The solids from the press are dried and then ground into meat and bone meal. Most independent renderers process only inedible material.
532:, synthetic detergents arrived, which displaced soaps in domestic and industrial washing. In the early 1950s, over half of the inedible fat market vanished. Diversion in these materials into animal feeds soon replaced the lost soap market and eventually became the single largest use for inedible fats.
468:
A further development came in the 19th century with the use of steam digesters: a tank used as a pressure cooker where steam was injected into the material being rendered. This process is a wet rendering process called "tanking" and was used for edible and inedible products, although better grades of
555:
Usually, materials used as raw materials in the rendering process are susceptible to spoilage. However, after rendering, the materials are much more resistant to spoiling. This is due to the application of heat either through cooking in the wet rendering process or the extraction of fluid in the dry
488:
meat industry in the United States—with its concentration in one geographic area—because it allowed the economic disposal of byproducts which would otherwise overwhelm the environment in that area. At first, small companies that sprang up near the packers did the rendering. Later the packers entered
394:
A variation on a dry process involves finely chopping the material, fluidizing it with hot fat, and then evaporating the mixture in one or more evaporator stages. Some inedible rendering is done using a wet process, which is generally a continuous process similar in some ways to that used for edible
373:
for use in food products. Edible rendering is generally carried out in a continuous process at low temperature (less than the boiling point of water). The process usually consists of finely chopping the edible fat materials (generally fat trimmings from meat cuts), heating them with or without added
386:
Materials that for aesthetic or sanitary reasons are not suitable for human food are the feedstocks for inedible rendering processes. Much of the inedible raw material is rendered using the "dry" method. This may be a batch or a continuous process in which the material is heated in a steam-jacketed
552:
would otherwise be a major disposal problem. As an example, the United States annually recycles more than 21 million metric tons of highly perishable and noxious organic matter. In 2004, U.S. industry produced over 8 million metric tons of products, of which 1.6 million metric tons were exported.
520:
Innovations came rapidly in the 20th century. Some of these were the uses for rendered products, and others were the rendering methods. In the 1920s, a batch dry rendering process was invented; the material was cooked in horizontal steam-jacketed cylinders (similar to the fertilizer dryers of the
551:
The rendering industry is one of the oldest recycling industries, and made possible the development of a large food industry. The industry takes what would otherwise be waste materials and makes useful products such as fuels, soaps, rubber, plastics, etc. At the same time, rendering reduces what
535:
The widespread use of "boxed beef", where the beef was cut into consumer portions at packing plants rather than local butcher shops and markets, meant that fat and meat scraps for renderers stayed at the packing plants and were rendered there by packer renderers, rather than by the independent
469:
edible products were made using the open kettle process. After the material is tanked, the free fat is run off, the remaining water ("tank water") run into a separate vat, and the solids removed and dried by pressing and steam-drying in a jacketed vessel. The tank water was either run into a
460:
over an open fire. This type of rendering is still done on farms to make lard (pork fat) for food purposes. With the development of steam boilers, it was possible to use steam-jacketed kettles to make a higher grade product, and reduce fire danger. From at least 1896,
272:. Rendering can be carried out on an industrial, farm, or kitchen scale. It can also be applied to non-animal products that are rendered down to pulp. The rendering process simultaneously dries the material and separates the fat from the
521:
day). Advantages claimed for the dry process were economy of energy, better protein yield, faster processing, and fewer noxious odors. Over the years, the wet "tanking" process was replaced with the dry process. By the end of
447:
by-products, which in turn allowed the development of a massive industrial-scale meat industry that made food more economical for the consumer. Rendering has been carried out for many centuries, primarily for
513:(1906), an exposé on the Chicago meat processing industry which created public outrage. His work helped the passage of the Pure Food and Drug Act of 1907 which paved the way for the creation of the
641:
Yellow grease is made by packers. All the refuse materials of the packing houses go into the yellow grease tank, together with any hogs which may die on the packers' hands.
356:
The processing plant may be operated by an independent company that buys input material from suppliers, or by a packing plant that produces the material in-house.
788:
308:, as well as entire carcasses of animals condemned at slaughterhouses and those that have died on farms, in transit, etc. The most common animal sources are
94:
49:
1400:
501:
were among the early pioneers of the U.S. rendering industry, with their personal backing and/or direct participation in the rendering industry.
336:
Whether the end products are used as human or animal food depends on the quality of input material and the processing methods and equipment.
539:
The rejection of animal fats by diet-conscious consumers led to a surplus of edible fats, and the resultant diversion into soapmaking and
200:
579:(mad-cow disease, BSE), which is also fatal to humans. Early in the 21st century, most countries tightened regulations to prevent this.
141:
113:
240:
222:
160:
63:
300:, but also includes restaurant grease, butcher shop trimmings, and expired meat from grocery stores. This material can include the
781:
576:
120:
55:
1274:
98:
127:
1434:
556:
rendering process. The fat obtained can be used as low-cost raw material in making grease, animal feed, soap, candles,
1424:
1330:
774:
753:
109:
264:
into more useful materials, or, more narrowly, to the rendering of whole animal fatty tissue into purified fats like
193:
187:
1315:
1264:
807:
87:
342:
In wet processing, either boiling water or steam is added to the material, separating fat into a floating phase.
204:
285:
1320:
634:
1429:
375:
1419:
679:
134:
733:
1076:
1003:
654:
1388:
1384:
1172:
957:
932:
724:
711:
1132:
1081:
988:
978:
952:
465:
has referred to lower-quality grades of tallow (cow or sheep fat) from animal rendering plants.
1335:
1187:
1152:
1071:
864:
593:
257:
1376:
1218:
588:
412:
1325:
1233:
1223:
1039:
833:
443:
The development of rendering was primarily responsible for the profitable utilization of
543:, displacing inedible fats and contributing to the market volatility of this commodity.
1294:
1213:
1167:
1101:
598:
504:
498:
490:
470:
297:
261:
1413:
1127:
494:
444:
575:
Meat and bone meal in animal feed was one route for the late-20th century spread of
1368:
1249:
998:
905:
828:
540:
522:
17:
1392:
1358:
1340:
1269:
1228:
1192:
1111:
1106:
1091:
885:
365:
Edible rendering processes are basically meat processing operations and produce
76:
1096:
1029:
947:
900:
509:
478:
1208:
1182:
1034:
993:
942:
608:
557:
388:
353:
Rendering may be done either in discrete batches or in a continuous process.
281:
1177:
517:. In 2012, the occupation of renderer appear in a list of "dirtiest jobs".
1289:
1284:
1162:
1157:
1044:
1008:
983:
973:
895:
890:
869:
859:
603:
561:
432:
260:
into stable, usable materials. Rendering can refer to any processing of
1299:
1279:
1254:
937:
838:
797:
735:
North
American Rendering: The Source of Essential High Quality Products
572:
rolling industry, providing lubrication when compressing steel sheets.
485:
321:
277:
1353:
1259:
1086:
854:
766:
565:
457:
453:
420:
408:
370:
317:
269:
345:
In dry processing, fat is released by dehydrating the raw material.
569:
305:
1013:
529:
474:
449:
428:
424:
416:
404:
366:
313:
309:
296:
In animal products, the majority of tissue processed comes from
273:
265:
770:
568:, derived from beef waste, is an important raw material in the
407:
and home cooks. In the kitchen, rendering is used to transform
726:
Essential
Rendering: All About The Animal By-Products Industry
514:
301:
172:
70:
29:
403:
Rendering of fats is also carried out on a kitchen scale by
636:
A Practical
Treatise on Animal and Vegetable Fats and Oils
484:
The pressure tank made possible the development of the
1308:
1242:
1201:
1145:
1120:
1064:
1057:
1022:
966:
925:
918:
878:
847:
821:
814:
374:steam, and then carrying out two or more stages of
339:The material may be processed by wet or dry means.
101:. Unsourced material may be challenged and removed.
332:The rendering process varies in a number of ways:
720:(April 2005), National Renderer's Association.
350:The temperature range used may be high or low.
782:
456:making. The earliest rendering was done in a
8:
64:Learn how and when to remove these messages
1061:
922:
818:
789:
775:
767:
759:Franco, Don and Swanson, Winfield (1996).
382:Rendering processes for inedible products
241:Learn how and when to remove this message
223:Learn how and when to remove this message
161:Learn how and when to remove this message
750:By-Products of the Meat-Packing Industry
256:is a process that converts waste animal
186:This article includes a list of general
684:United States Department of Agriculture
625:
481:. The solids were used for fertilizer.
361:Rendering processes for edible products
7:
1380:
99:adding citations to reliable sources
1396:
738:. National Renderer's Association.
729:. National Renderer's Association.
192:it lacks sufficient corresponding
25:
743:Rendering, The Invisible Industry
633:Brannt, William Theodore (1896).
477:or protein concentrate to add to
45:This article has multiple issues.
27:Conversion of waste animal tissue
1395:
1387:
1379:
1372:
1371:
1362:
1352:
577:bovine spongiform encephalopathy
177:
110:"Rendering" animal products
75:
34:
1188:Indirect grilling/Plank cooking
86:needs additional citations for
53:or discuss these issues on the
560:, and as a feed-stock for the
1:
473:or it was evaporated to make
639:. H. C. Baird. p. 110.
547:Advantages and disadvantages
1030:Bain-marie (Double boiling)
754:University of Chicago Press
653:Ellin, Abby (Sep 3, 2012).
1451:
1316:List of cooking appliances
808:List of cooking techniques
706:Lyman, Howard, F. (1998).
1349:
805:
655:"The Seven Dirtiest Jobs"
741:Clemen, Rudolph (1978).
489:the rendering industry.
1321:List of cooking vessels
891:Grilling (charbroiling)
431:, and chicken fat into
207:more precise citations.
896:Roasting (traditional)
761:The Original Recyclers
376:centrifugal separation
763:, APPI, FPRF and NRA.
536:rendering companies.
1435:Industrial processes
748:Young, H.H. (1927).
712:Simon & Schuster
95:improve this article
304:tissue, bones, and
1425:Cooking techniques
1193:Stir frying (chao)
745:, Aero Publishers.
701:General references
328:Process variations
280:, yielding a fat
1407:
1406:
1336:Food preservation
1260:Burying in ground
1153:Carryover cooking
1141:
1140:
1053:
1052:
914:
913:
860:Roasting (modern)
723:Meeker, David L.
594:Animal euthanasia
399:Kitchen rendering
251:
250:
243:
233:
232:
225:
171:
170:
163:
145:
68:
18:Kitchen rendering
16:(Redirected from
1442:
1399:
1398:
1391:
1383:
1382:
1375:
1374:
1369:Drink portal
1367:
1366:
1365:
1357:
1356:
1331:Food preparation
1219:Pressure cooking
1062:
923:
819:
791:
784:
777:
768:
732:Burnham, Frank.
694:
693:
691:
690:
676:
670:
669:
667:
665:
650:
644:
643:
630:
620:Inline citations
589:Animal slaughter
413:clarified butter
246:
239:
228:
221:
217:
214:
208:
203:this article by
194:inline citations
181:
180:
173:
166:
159:
155:
152:
146:
144:
103:
79:
71:
60:
38:
37:
30:
21:
1450:
1449:
1445:
1444:
1443:
1441:
1440:
1439:
1410:
1409:
1408:
1403:
1363:
1361:
1359:Food portal
1351:
1345:
1326:Outdoor cooking
1304:
1238:
1234:Thermal cooking
1224:Pressure frying
1197:
1137:
1116:
1049:
1040:Double steaming
1018:
962:
910:
874:
843:
834:Hot salt frying
810:
801:
795:
718:Render Magazine
703:
698:
697:
688:
686:
678:
677:
673:
663:
661:
652:
651:
647:
632:
631:
627:
622:
617:
585:
549:
441:
401:
384:
363:
330:
298:slaughterhouses
294:
262:animal products
247:
236:
235:
234:
229:
218:
212:
209:
199:Please help to
198:
182:
178:
167:
156:
150:
147:
104:
102:
92:
80:
39:
35:
28:
23:
22:
15:
12:
11:
5:
1448:
1446:
1438:
1437:
1432:
1427:
1422:
1412:
1411:
1405:
1404:
1350:
1347:
1346:
1344:
1343:
1338:
1333:
1328:
1323:
1318:
1312:
1310:
1306:
1305:
1303:
1302:
1297:
1292:
1287:
1282:
1277:
1272:
1267:
1262:
1257:
1252:
1246:
1244:
1240:
1239:
1237:
1236:
1231:
1226:
1221:
1216:
1211:
1205:
1203:
1199:
1198:
1196:
1195:
1190:
1185:
1180:
1175:
1170:
1168:Caramelization
1165:
1160:
1155:
1149:
1147:
1143:
1142:
1139:
1138:
1136:
1135:
1130:
1124:
1122:
1118:
1117:
1115:
1114:
1109:
1104:
1102:Shallow frying
1099:
1094:
1089:
1084:
1079:
1074:
1068:
1066:
1059:
1055:
1054:
1051:
1050:
1048:
1047:
1042:
1037:
1032:
1026:
1024:
1020:
1019:
1017:
1016:
1011:
1006:
1001:
996:
991:
986:
981:
976:
970:
968:
964:
963:
961:
960:
955:
950:
945:
940:
935:
929:
927:
920:
916:
915:
912:
911:
909:
908:
903:
898:
893:
888:
882:
880:
876:
875:
873:
872:
867:
862:
857:
851:
849:
845:
844:
842:
841:
836:
831:
825:
823:
816:
812:
811:
806:
803:
802:
796:
794:
793:
786:
779:
771:
765:
764:
757:
746:
739:
730:
721:
715:
702:
699:
696:
695:
671:
645:
624:
623:
621:
618:
616:
613:
612:
611:
606:
601:
599:Dead Horse Bay
596:
591:
584:
581:
548:
545:
505:Upton Sinclair
499:Lucius Darling
491:Gustavus Swift
440:
437:
400:
397:
383:
380:
362:
359:
358:
357:
354:
351:
348:
347:
346:
343:
337:
329:
326:
293:
290:
284:and a protein
249:
248:
231:
230:
185:
183:
176:
169:
168:
83:
81:
74:
69:
43:
42:
40:
33:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
1447:
1436:
1433:
1431:
1430:Meat industry
1428:
1426:
1423:
1421:
1418:
1417:
1415:
1402:
1394:
1390:
1386:
1378:
1370:
1360:
1355:
1348:
1342:
1339:
1337:
1334:
1332:
1329:
1327:
1324:
1322:
1319:
1317:
1314:
1313:
1311:
1307:
1301:
1298:
1296:
1293:
1291:
1288:
1286:
1283:
1281:
1278:
1276:
1273:
1271:
1268:
1266:
1263:
1261:
1258:
1256:
1253:
1251:
1248:
1247:
1245:
1241:
1235:
1232:
1230:
1227:
1225:
1222:
1220:
1217:
1215:
1212:
1210:
1207:
1206:
1204:
1200:
1194:
1191:
1189:
1186:
1184:
1181:
1179:
1176:
1174:
1171:
1169:
1166:
1164:
1161:
1159:
1156:
1154:
1151:
1150:
1148:
1144:
1134:
1131:
1129:
1128:Gentle frying
1126:
1125:
1123:
1119:
1113:
1110:
1108:
1105:
1103:
1100:
1098:
1095:
1093:
1090:
1088:
1085:
1083:
1080:
1078:
1075:
1073:
1070:
1069:
1067:
1063:
1060:
1056:
1046:
1043:
1041:
1038:
1036:
1033:
1031:
1028:
1027:
1025:
1023:Indirect heat
1021:
1015:
1012:
1010:
1007:
1005:
1002:
1000:
997:
995:
992:
990:
987:
985:
982:
980:
977:
975:
972:
971:
969:
965:
959:
956:
954:
951:
949:
946:
944:
941:
939:
936:
934:
931:
930:
928:
924:
921:
917:
907:
904:
902:
899:
897:
894:
892:
889:
887:
884:
883:
881:
877:
871:
868:
866:
863:
861:
858:
856:
853:
852:
850:
846:
840:
837:
835:
832:
830:
827:
826:
824:
820:
817:
813:
809:
804:
799:
792:
787:
785:
780:
778:
773:
772:
769:
762:
758:
755:
751:
747:
744:
740:
737:
736:
731:
728:
727:
722:
719:
716:
713:
709:
705:
704:
700:
685:
681:
675:
672:
660:
656:
649:
646:
642:
638:
637:
629:
626:
619:
614:
610:
607:
605:
602:
600:
597:
595:
592:
590:
587:
586:
582:
580:
578:
573:
571:
567:
563:
559:
553:
546:
544:
542:
541:oleochemicals
537:
533:
531:
526:
524:
518:
516:
512:
511:
506:
502:
500:
496:
495:Nelson Morris
492:
487:
482:
480:
476:
472:
466:
464:
463:yellow grease
459:
455:
451:
446:
445:meat industry
438:
436:
434:
430:
426:
422:
418:
414:
410:
406:
398:
396:
392:
390:
381:
379:
377:
372:
368:
360:
355:
352:
349:
344:
341:
340:
338:
335:
334:
333:
327:
325:
323:
319:
315:
311:
307:
303:
299:
292:Input sources
291:
289:
287:
283:
279:
275:
271:
267:
263:
259:
255:
245:
242:
227:
224:
216:
213:November 2022
206:
202:
196:
195:
189:
184:
175:
174:
165:
162:
154:
151:February 2019
143:
140:
136:
133:
129:
126:
122:
119:
115:
112: –
111:
107:
106:Find sources:
100:
96:
90:
89:
84:This article
82:
78:
73:
72:
67:
65:
58:
57:
52:
51:
46:
41:
32:
31:
19:
1420:Cooking fats
1202:Device-based
1146:Mixed medium
999:Slow cooking
829:Dry roasting
760:
749:
742:
734:
725:
717:
707:
687:. Retrieved
683:
680:"FAQ on BSE"
674:
662:. Retrieved
658:
648:
640:
635:
628:
574:
554:
550:
538:
534:
527:
523:World War II
519:
508:
503:
483:
467:
462:
442:
402:
393:
385:
364:
331:
295:
253:
252:
237:
219:
210:
191:
157:
148:
138:
131:
124:
117:
105:
93:Please help
88:verification
85:
61:
54:
48:
47:Please help
44:
1401:WikiProject
1341:Food safety
1229:Slow cooker
1214:Microwaving
1107:Stir frying
1092:Deep frying
886:Charbroiler
714:, New York.
205:introducing
1414:Categories
1275:Fermenting
1209:Air frying
1158:Barbecuing
1097:Pan frying
1077:Blackening
1004:Smothering
948:Parboiling
901:Rotisserie
848:Convection
822:Conduction
800:techniques
708:Mad Cowboy
689:2017-01-28
664:29 January
615:References
564:industry.
510:The Jungle
479:fertilizer
369:or edible
188:references
121:newspapers
50:improve it
1183:Fricassee
1173:Deglazing
1065:High heat
1058:Fat-based
1035:Sous-vide
994:Simmering
958:Reduction
943:Decoction
933:Blanching
926:High heat
879:Radiation
609:Whale oil
558:biodiesel
427:fat into
389:bone meal
282:commodity
254:Rendering
56:talk page
1393:Cookbook
1377:Category
1309:See also
1285:Pickling
1243:Non-heat
1163:Braising
1133:Sweating
1121:Low heat
1112:Sautéing
1082:Browning
1045:Steaming
1009:Steeping
989:Poaching
984:Infusion
979:Creaming
974:Coddling
967:Low heat
953:Shocking
906:Toasting
870:Barbecue
659:ABC News
604:Flensing
583:See also
562:chemical
433:schmaltz
1385:Commons
1300:Souring
1295:Salting
1280:Juicing
1255:Brining
1072:Basting
1014:Stewing
938:Boiling
865:Smoking
839:Searing
798:Cooking
486:Chicago
439:History
322:poultry
278:protein
201:improve
135:scholar
1270:Drying
1265:Curing
1178:Flambé
1087:Frying
855:Baking
566:Tallow
528:After
507:wrote
497:, and
458:kettle
454:candle
421:tallow
409:butter
371:tallow
320:, and
318:mutton
270:tallow
258:tissue
190:, but
137:
130:
123:
116:
108:
1290:Purée
1250:Aging
570:steel
471:sewer
419:into
411:into
405:chefs
306:offal
302:fatty
142:JSTOR
128:books
666:2014
530:WWII
475:glue
452:and
450:soap
429:lard
425:pork
417:suet
367:lard
314:pork
310:beef
286:meal
276:and
274:bone
266:lard
114:news
919:Wet
815:Dry
515:FDA
268:or
97:by
1416::
752:,
710:.
682:.
657:.
493:,
435:.
423:,
415:,
391:.
324:.
316:,
312:,
288:.
59:.
790:e
783:t
776:v
756:.
692:.
668:.
244:)
238:(
226:)
220:(
215:)
211:(
197:.
164:)
158:(
153:)
149:(
139:·
132:·
125:·
118:·
91:.
66:)
62:(
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
