Gelatin (Encyclopedia of Food & Culture)
GELATIN. Gelatin (also gelatine, jelly in Britain, jelly powder in Canada, and gelée in France) is a flavorless, transparent thickener derived from animal collagen that dissolves when heated and congeals when cooled, allowing foods to set. This versatile ingredient provides unique textural and sensory properties to both savory and sweet foodstuffs such as mousses, gummy bears, Turkish Delight, nougat, jellied soups, Bavarian cream, aspic, and Jell-O.
Gelatin is composed of protein molecules, made up of chains of amino acids. When placed in liquid, the molecules swell and then dissolve, and the chains separate. After cooling, they re-form as tightly as before. In the warmth of the mouth, they melt, providing excellent flavor release. This property and gelatin's easy digestability and absorption by the body makes gelled desserts appropriate for children, invalids, and the elderly.
Nutritional value of gelatin was recognized as early as the Napoleonic Wars (1800815) when the French used it as a source of protein during the English blockade. Commercial gelatin contains no fat or cholesterol and few calories, making it popular with people who have diet and heart concerns. Commercial manufacturers claim that gelatin promotes nail and hair growth, as well as flexible joints and healthy bones. However, the protein in gelatin is missing an amino acid and thus is not absorbed as a complete protein by the body.
The discovery of gelatin was probably serendipitous: When animal bones and hides are boiled in water, the broth that results will set upon cooling. From the Middle Ages through the eighteenth century, making gelatin was a daylong, laborious process in which cattle hooves were boiled for six hours. The stock was clarified as it dripped through a jelly bag, boiled again, and then allowed to sit. Not surprisingly, production was limited to wealthy households with many servants. Another early
Today, the substance is manufactured commercially all over the world. In the United States most gelatin is derived from pig skin. Strictly speaking, this is not a kosher practice (although interpretations vary), and it is not permissible under Islamic dietary law. An alternative, isinglass (made from the air bladders of sturgeon), is acceptable to the religious and vegetarians. Another alternative is agar, made from a variety of red seaweed, commonly used in Japan where it is known as kanten and used in the manufacture of ice cream. Cattle form the basis of gelatin in France and Britain, raising safety concerns about transmission of mad cow disease even in the United States where some gelatin is imported from Europe.
Commercially manufactured gelatin is packaged in ¼-ounce envelopes of desiccated granules; paper-thin sheets, known as leaves (used in jelled Central and Eastern European desserts and aspics); and meltable blocks (Great Britain). In Latin America, gelatin is often mixed with milk or cream instead of water for the popular creamy desserts. In Russia, gelatin encases pigs' feet and other meats.
Aside from home and restaurant cooking, gelatin has wide application in the food industry where its functional properties are used to gel, thicken, stabilize, emulsify, bind, film, foam and whip prepared foods. Among other items, gelatin is incorporated into marshmallows, cake mixes, frostings, bakery glazes, meringues, ice cream, coffee, and powdered milk.
Elaborate molded jellies began to grace aristocratic British banquet tables in the fourteenth century. In the Late Medieval period (the 1400s) through the 1500s, cooks made savory and sweet jellied dishes using meat, chopped fine, mixed with cream or almond milk that was flavored with spices, rosewater, or sugar to fashion creations known as cullis, gellys, or brawn. In 1754, the first English patent for the manufacture of gelatin was granted. During the Victorian era, copper, and later aluminum, molds were introduced, which made possible the presentation of tall, shimmering creations. Unflavored dried gelatin became available in 1842 from the J and G Company of Edinburgh, Scotland.
Gelatin had an esteemed role in classic French cuisine. Escoffier's legendary Guide Culinaire (1903) includes a chapter on aspic jellies (savory gels) in which the great chef named two kinds: one flavored with champagne; the other with sherry, Marsala, or Madeira. Surprisingly, he mused that aspics might be even more important than stock, the bastion of Gallic cooking, because a cold meat, poultry, or fish entree (known as chaud-froid) is nothing without its glimmering coating of aspic. He warned that the value of the aspic decreased in direct proportion to its increasing firmness. The ideal was a softer consistency so aspic could even be served in a sauceboat. Gelatin also figured in many classic French desserts like blanc-mange, charlottes, mousses, and Bavarian creams.
Gelatin in the United States
In America, in 1845, Peter Cooper, inventor of the steam locomotive, secured a patent for a gelatin dessert powder called Portable Gelatin, requiring only the addition of hot water. The same year, the J and G Company began exporting its Cox Gelatin to the United States. The new formulas never gained much popularity, however, and as late as 1879 when the classic Housekeeping in Old Virginia was published, editor Marion Cabell Tyrer, while admitting that jelly made of calves and hogs was "more troublesome," claimed it was more nutritious than Cox's or Nelson's desiccated formulas. Plymouth Rock Gelatin Company of Boston patented its Phosphated Gelatin in 1889. In 1894, Charles Knox introduced granulated gelatin, making the brand something of a household word. This opened the way for a plethora of American recipes that gained popularity, particularly during the 1950s when chiffon pie and tomato aspic (made of gelatin and tomato juice) became staples.
Although Jell-O is considered déclassé in upscale restaurants, gelatin was resurrected and frenchfied by American chefs in the late 1990s, who reverted to calling the sweets "gelées." These creative formulas have been limited only by imagination since virtually any liquid can be usedoffee, champagne, grape and beet juice, rosé wine, sangria, and fruit poaching liquids. What began in the Middle Ages as an elite food has come full circle and returned to gourmet status.
See also Escoffier, Georges-Auguste; Medieval Banquet;Proteins and Amino Acids; Icon Foods; Women and Food.
Wyman, Carolyn. JELL-O: A Biography, The History and Mystery of "America's Most Famous Dessert." San Diego, Calif., New York and London: Harcourt, 2001. Contains material on gelatin as well.
Shapiro, Laura. Perfection Salad: Women and Cooking at the Turn of the Century. New York: Farrar, Straus and Giroux, 1986.
Belluscio, Lynne. The JELL-O Reader. Le Roy, N.Y.: Le Roy Pennysaver, 1998. A collection of forty articles by the director of the Le Roy Historical Society. Also contains material on gelatin.
Berzok, Linda Murray. "My Mother's Recipes: The Diary of a Swedish American Daughter and Mother." In Pilaf, Pozole, and Pad Thai: American Women and Ethnic Food, edited by Sherrie A. Inness. Amherst, Mass.: University of Massachusetts Press, 2001. The social meaning, for women, of Jell-O molded salads.
Linda Murray Berzok
Gelatin (How Products are Made)
Gelatin is a protein substance derived from collagen, a natural protein present in the tendons, ligaments, and tissues of mammals. It is produced by boiling the connective tissues, bones and skins of animals, usually cows and pigs. Gelatin's ability to form strong, transparent gels and flexible films that are easily digested, soluble in hot water, and capable of forming a positive binding action have made it a valuable commodity in food processing, pharmaceuticals, photography, and paper production.
As a foodstuff, gelatin is the basis for jellied desserts; used in the preservation of fruit and meat, and to make powdered milk, merinque, taffy, marshmallow, and fondant. It is also used to clarify beer and wine. Gelatin's industrial applications include medicine capsules, photographic plate coatings, and dying and tanning supplies.
Until the mid-nineteenth century, making gelatin was a laborious task. Calves' feet were loaded into a large kettle that was then placed over a fire. The feet were boiled for several hours after which the liquid was strained and the bones were discarded. After setting for 24 hours, a layer of fat would rise to the top. This was skimmed off and discarded. Sweeteners and or flavorings were added to the liquid and it was poured into molds and allowed again to set.
By the 1840s, however, some producers were grinding the set gelatin into a fine powder or cutting it into sheets. One of them was Charles B. Knox, a salesman from Johnston, New York, who hit on the idea of making gelatin more convenient after watching his wife Rose make it in their kitchen. Knox packaged dried sheets of gelatin and then hired salesmen to travel door-to-door to show women how to add liquid to the sheets and use it to make aspics, molds, and desserts. In 1896, Rose Knox published Dainty Desserts, a book of recipes using Knox gelatin.
The first patent for a gelatin dessert was issued in 1845 to industrialist and inventor Peter Cooper. Cooper had already made a name for himself as the inventor of the Tom Thumb steam engine. He had also made a fortune in the manufacture of glue, a process similar to that for making gelatin.
In 1897, Pearl B. Wait, a carpenter and cough medicine manufacturer, developed a fruit-flavored gelatin. His wife, May Davis Wait, named his product Jell-O. The new product was not immediately popular and Wait sold the rights to the process to Orator Francis Woodward, owner of the Genesee Food Company, for $450. Sales continued to limp along until 1902 when an aggressive advertising campaign in Ladies Home Journal magazine generated enormous interest. Sales jumped to $250,000.
The use of gelatin in food preparation increased six-fold in the 40-year period from 1936-1976. Today, 400 million packages of Jello-O are produced each year. Over a million packages are purchased or eaten each day.
In the field of photography, gelatin was introduced in the late 1870s as a substitute for wet collodion. It was used to coat dry photographic plates, marking the beginning of modern photographic methods. Gelatin's
Animal bones, skins, and tissue are obtained from slaughterhouses. Gelatin processing plants are usually located nearby so that these animal byproducts can be quickly processed.
Acids and alkalines such as caustic lime or sodium carbonate are used to extract minerals and bacteria from the animal parts. They are either produced in the food processing plant or purchased from outside vendors.
Sweeteners, flavorings, and colorings are added in the preparation of food gelatin. These can be in liquid or powdered forms and are purchased from outside vendors.
The Manufacturing Process
Inspection and cutting
- 1 When the animal parts arrive at the food processing plant, they are inspected for quality. Rotted parts are discarded. Then, the bones, tissues, and skins are loaded into chopping machines that cut the parts into small pieces of about Sin (12.7cm) in diameter.
Degreasing and roasting
- 2 The animal parts are passed under high-pressure water sprays to wash away debris. They are then degreased by soaking them in hot water to reduce the fat content to about 2%. A conveyer belt moves the degreased bones and skins to an industrial dryer where they are roasted for approximately 30 minutes at about 200° F (100° C).
Acid and akaline treatment
- 3 The animal parts are soaked in vats of lime or some other type of acid or akali for approximately five days. This process removes most of the minerals and bacteria and facilitates the release of collagen. The acid wash is typically a 4% hydrochloric acid with a pH of less than 1.5. The alkaline wash is a potassium or sodium carbonate with a pH above 7.
- 4 The pieces of bone, tissue, and skin are loaded into large aluminum extractors and boiled in distilled water. A tube running from the extractor allows workers to draw off the liquid that now contains gelatin. The liquid is sterilized by flash-heating it to about 375° F (140° C) for approximately four seconds.
Evaporating and grinding
- 5 From the extractor, the liquid is piped through filters to separate out bits of
Flavoring and coloring
- 6 If the gelatin is to be used by the food industry, sweeteners, flavorings, and colorings may be added at this point. Pre-set amounts of these additives are thoroughly mixed into the powdered gelatin.
The packaging process is automated, with preset amounts of gelatin poured into overhead funnels through which the gelatin flows down into bags made of either polypropylene or multi-ply paper. The bags are then vacuumed sealed.
Gelatin manufacturers must adhere to stringent national and international food processing requirements. These regulations include but are not limited to cleanliness of the plant, equipment and employees; and allowable percentages of additives, flavorings, and colorings.
Automated and computerized technologies allow the processors to preset and monitor ingredient amounts, time and temperature, acidity and alkalinity, and flow levels. Valves are installed along pipelines to allow for continuous sampling of the product.
Gelatin is processed to varying "bloom" values that measure the gel strength or firmness. The desired strength corresponds to the manner in which the gelatin will be used. The bloom value is technically measured and monitored throughout the production process.
Since 1986 when the presence of bovine spongiform encephalopathy (BSE), also known as mad cow disease, was reported in Great Britain, there has been much concern about the processing of beef bones for the production of gelatin. In 1989, the United States Food and Drug Administration (FDA) banned the importation of cattle from the Department of Agriculture's list of of BSE-designated countries. However, a 1994 FDA ruling allowed the continued importation of bones and tissues for the production of pharmaceutical grade gelatin.
By 1997, however, the FDA held hearings to reconsider its decision. After interviewing gelatin processors, the agency found that while gelatin has not been implicated in the spread of BSE, officials are not convinced that the manufacturing processing is extracting all possible agents that are responsible for the disease. It was generally agreed that beef sources carry more of a risk than those from pork, that bones carry a higher risk than skins, and that alkaline processing is more effective than the acid-extraction method. These findings will certainly affect the gelatin-processing industry in the next century.
Where to Learn More
Harvey Lang, Jenifer, ed. Larousse Gastronomique. New York: Crown Publishers, 1988, reprinted 1998.
Marwick, Charles. "BSE sets agenda for imported gelatin." Journal of American Medical Association (June 4, 1997): 1,659.
Leiner Davis Gelatin. http://www.gelatin.com/ (June 29, 1999).
Kraft Foods. http://www.kraftfoods.com/ (June 29, 1999).
Sterling Gelatin. http://www.sterlinggelatin.com (June 29, 1999).