# Ketchup

For other uses, see Ketchup (disambiguation).
Alternative names A dish of tomato ketchup Catsup, ketsup, condiment. Condiment Tomatoes, sugar or high fructose corn syrup, vinegar, salt, spices and seasonings Cookbook: Ketchup  Media: Ketchup

Ketchup, or catsup or ketsup , is a table sauce. Traditionally, recipes featured ketchups made from egg whites, mushrooms, oysters, mussels, walnuts, or other foods,[1][2] but in modern times the unmodified term usually refers to tomato ketchup. Tomato sauce is the more common term in Australia, New Zealand, and India, and is almost exclusively used in South Africa.

Ketchup is a sweet and tangy sauce, typically made from tomatoes, sweetener, vinegar, and assorted seasonings and spices. Seasonings vary by recipe, but commonly include onions, allspice, cloves, cinnamon, garlic, and sometimes celery.[3]

Heinz tomato ketchup is the market leader, with an 82% market share in the UK and a 60% share in the US market.[4][5]

Tomato ketchup is often used as a condiment to various dishes that are usually served hot: French fries, hamburgers, hot sandwiches, hot dogs, cooked eggs, and grilled or fried meat. Ketchup is sometimes used as the basis for, or an ingredient in, other sauces and dressings, and it is also used as an additive flavoring for snacks like potato chips.

## History

### Pickled fish and spices

In the 17th century, the Chinese mixed a concoction of pickled fish and spices and called it (in the Amoy dialect) kôe-chiap or kê-chiap (鮭汁, Mandarin Chinese guī zhī, Cantonese gwai1 zap1) meaning the brine of pickled fish (鮭, salmon; 汁, juice) or shellfish.[6] By the early 18th century, the table sauce had made it to the Malay states (present day Malaysia and Singapore), where it was tasted by English colonists. The Indonesian-Malay word for the sauce was kecap (pronounced "kay-chap"). That word evolved into the English word "ketchup".[7] English settlers then took ketchup with them to the American colonies.[1]

The term Ketchup was used in 1690 in the Dictionary of the Canting Crew which was well acclaimed in North America.[8] The spelling "catchup" may have also been used in the past.[9]

### Mushroom ketchup

Main article: Mushroom ketchup
Homemade mushroom ketchup in a plastic tub

In the United Kingdom, preparations of ketchup were historically and originally prepared with mushrooms as a primary ingredient, rather than tomatoes.[10][11][12] Ketchup recipes began to appear in British and then American cookbooks in the 18th century. In a 1742 London cookbook, the fish sauce had already taken on a very British flavor, with the addition of shallots and mushrooms. The mushrooms soon became a main ingredient, and from 1750 to 1850 the word ketchup began to mean any number of thin dark sauces made of mushrooms or even walnuts.[13] In the United States, mushroom ketchup dates back to at least 1770, and was prepared by British colonists in "English speaking colonies in North America".[14] In contemporary times, mushroom ketchup is available in the UK, although it is not a commonly used condiment.[15]

### Tomato ketchup

Tomato ketchup and other condiments
Tomatoes and tomato ketchup

Many variations of ketchup were created, but the tomato-based version did not appear until about a century later after other types. One version of the recipe was created by Sandy Addison and published in an American cookbook, The Sugar House Book.[16]

1. Get [the tomatoes] quite ripe on a dry day, squeeze them with your hands till reduced to a pulp, then put half a pound of fine salt to one hundred tomatoes, and boil them for two hours.
2. Stir them to prevent burning.
3. While hot press them through a fine sieve, with a silver spoon till nought but the skin remains, then add a little mace, 3 nutmegs, allspice, cloves, cinnamon, ginger, and pepper to taste.
4. Boil over a slow fire till quite thick, stir all the time.
5. Bottle when cold.
6. One hundred tomatoes will make four or five bottles and keep good for two or three years.

This early recipe for "Tomata Catsup" from 1817 still has the anchovies that betray its fish-sauce ancestry:[13]

1. Gather a gallon of fine, red, and full ripe tomatas; mash them with one pound of salt.
2. Let them rest for three days, press off the juice, and to each quart add a quarter of a pound of anchovies, two ounces of shallots, and an ounce of ground black pepper.
3. Boil up together for half an hour, strain through a sieve, and put to it the following spices; a quarter of an ounce of mace, the same of allspice and ginger, half an ounce of nutmeg, a drachm of coriander seed, and half a drachm of cochineal.
4. Pound all together; let them simmer gently for twenty minutes, and strain through a bag: when cold, bottle it, adding to each bottle a wineglass of brandy. It will keep for seven years.

By the mid-1850s, the anchovies had been dropped.[13]

James Mease published another recipe in 1812. In 1824, a ketchup recipe using tomatoes appeared in The Virginia Housewife (an influential 19th-century cookbook written by Mary Randolph, Thomas Jefferson's cousin). American cooks also began to sweeten ketchup in the 19th century.[17]

As the century progressed, tomato ketchup began its ascent in popularity in the United States. Ketchup was popular long before fresh tomatoes were.[18] Many Americans[who?] continued to question whether it was safe to eat raw tomatoes. However, they were much less hesitant to eat tomatoes as part of a highly processed product that had been cooked and infused with vinegar and spices.[18]

Tomato ketchup was sold locally by farmers. Jonas Yerkes is credited as the first American to sell tomato ketchup in a bottle.[19] By 1837, he had produced and distributed the condiment nationally.[20] Shortly thereafter, other companies followed suit. F. & J. Heinz launched their tomato ketchup in 1876.[21] Heinz tomato ketchup was advertised: "Blessed relief for Mother and the other women in the household!", a slogan which alluded to the lengthy and onerous process required to produce tomato ketchup in the home.[22] With industrial ketchup production and a need for better preservation there was a great increase of sugar in ketchup, leading to our modern sweet and sour formula.[13]

The Webster's Dictionary of 1913 defined ‘catchup’ as: “table sauce made from mushrooms, tomatoes, walnuts, etc. [Also written as ketchup].”

Modern ketchup emerged in the early years of the 20th century, out of a debate over the use of sodium benzoate as a preservative in condiments. Harvey W. Wiley, the "father" of the Food and Drug Administration in the US, challenged the safety of benzoate which was banned in the 1906 Pure Food and Drug Act. In response, entrepreneurs including Henry J. Heinz, pursued an alternative recipe that eliminated the need for that preservative.[3]

Prior to Heinz (and his fellow innovators), commercial tomato ketchups of that time were watery and thin, in part due to the use of unripe tomatoes, which were low in pectin.[23] They had less vinegar than modern ketchups; by pickling ripe tomatoes, the need for benzoate was eliminated without spoilage or degradation in flavor. But the changes driven by the desire to eliminate benzoate also produced changes[clarification needed] that some experts (such as Andrew F. Smith[24]) believe were key to the establishment of tomato ketchup as the dominant American condiment.

### Later innovations

In fast food outlets, ketchup is often dispensed in small packets. Diners tear the side or top and squeeze the ketchup out of the ketchup packets. In 2011, Heinz began offering a new measured-portion package, called the "Dip and Squeeze" packet, which allowed the consumer to either tear the top off the package and squeeze the contents out, as with the traditional packet, or, in the alternative, tear the front off the package and use the package as a dip cup of the type often supplied with certain entreés.[25]

Previously, fast food outlets dispensed ketchup from pumps into paper cups. This method has made a resurgence in the first decade of the 21st century with cost and environmental concerns over the increasing use of individual packets.

In October 2000, Heinz introduced colored ketchup products called EZ Squirt, which eventually included green (2000), purple (2001), pink (2002), orange (2002), teal (2002), and blue (2003).[26] These products were made by adding food coloring to the traditional ketchup. As of January 2006 these products were discontinued.[27]

## Terminology

The term used for the sauce varies. Ketchup is the dominant term in American English, Canadian English, and British English, although catsup is commonly used in some southern US states and Mexico.[28] In these dialects, tomato sauce refers to pasta sauce, and is not a synonym for ketchup. Tomato sauce is more common in some other English-speaking countries (Australia, India, and New Zealand) or used almost exclusively (South Africa). Red sauce is used in Welsh English, Scottish English and some parts of England, such as the Black Country, and in South London, often contrasting with brown sauce with which it is often served—but in Canadian and American English, "red sauce" refers to various tomato-based sauces commonly paired with pasta dishes, and is not a synonym for ketchup.

The etymology of the word ketchup is unclear, with multiple competing theories.[29]

### China theory

One prominent theory is that the word came to English from the Cantonese "keh jup" (茄汁 ke2 zap1, a shorterned version of 蕃茄汁 faan1 ke2 zap1 "tomato sauce; tomato juice").[30]

An alternative theory is that the word derives from one of two words from the Fujian region of coastal southern China: "kôe-chiap" (in Xiamen (Amoy)) or "kê-chiap"[31] (in Guangzhou (Canton)). Both of these words (鮭汁, kôe-chiap and kê-chiap) come from the Amoy dialect of China, where it meant the brine of pickled fish (鮭, salmon; 汁, juice) or shellfish.[6] There are citations of "koe-chiap" in the Dictionary of the Vernacular or Spoken Language of the Amoy (London; Trudner) from 1873, defined as "brine of pickled fish or shell-fish."

### Malay theory

Ketchup may have[7] entered the English language from the Malay word kicap (pron. "kichap", also spelled kecap, ketjap). Originally meaning "fish sauce", the word itself derives the Chinese terms[32] above.

In Indonesian cuisine, which is similar to Malay, the term kecap refers to fermented savory sauces. Two main types are well known in their cuisine: kecap asin which translates to 'salty kecap' in Indonesian (a salty soy sauce) and kecap manis or literally 'sweet kecap' in Indonesian. Kecap manis is a sweet soy sauce that is a mixture of soy sauce with brown sugar, molasses, garlic, ginger, anise, coriander and a bay leaf reduced over medium heat until rather syrupy. A third type, kecap ikan, meaning "fish kecap" is fish sauce similar to the Thai nam pla or the Philippine patis. It is not, however, soy-based.

### European-Arabic theory

American anthropologist E.N. Anderson relies on Elizabeth David to claim that ketchup is a cognate of the French escaveche, meaning "food in sauce," but gives no further authority.[33] The word also exists in Spanish and Portuguese forms as escabeche, "a sauce for pickling", which culinary historian Karen Hess traced back to Arabic Kabees, or "pickling with vinegar". The term was anglicized to caveach, a word first attested in the late 17th century, at the same time as ketchup.[29]

### Early uses in English

The word entered the English language in Britain during the late 17th century, appearing in print as catchup (1690) and later as ketchup (1711). The following is a list of early quotations collected by the Oxford English Dictionary.

The first published recipe: it included mushrooms, anchovies and horseradish.
• 1730, Jonathan Swift, A Panegyrick on the Dean Wks. 1755 IV. I. 142
• And, for our home-bred British cheer, Botargo, catsup, and caveer.
• 1748, Sarah Harrison, The Housekeeper's Pocket-Book and Compleat Family Cook. i. (ed. 4) 2,
• I therefore advise you to lay in a Store of Spices, ... neither ought you to be without ... Kitchup, or Mushroom Juice.
• 1751, Mrs. Hannah Glasse, Cookery Bk. 309
• It will taste like foreign Catchup.
• 1817, George Gordon Byron, Beppo viii,
• Buy in gross ... Ketchup, Soy, Chili~vinegar, and Harvey.
• 1832, Vegetable Substances Used for the Food of Man 333
• One ... application of mushrooms is ... converting them into the sauce called Catsup.
• 1840, Charles Dickens, Barnaby Rudge (1849) 91/1
• Some lamb chops (breaded, with plenty of ketchup).
• 1845, Eliza Acton, Modern Cookery v. (1850) 136 (L.)
• Walnut catsup.
• 1862, Macmillan's Magazine. Oct. 466
• He found in mothery catsup a number of yellowish globular bodies.
• 1874, Mordecai C. Cooke, Fungi; Their Nature, Influence and Uses 89
• One important use to which several ... fungi can be applied, is the manufacture of ketchup.

The spelling catsup seems to have appeared first from the pen of Jonathan Swift, in 1730. Despite this origin, the spelling is largely unused in Britain today, where it is often assumed to be an Americanism.

### "Fancy" ketchup

Some ketchup in the U.S. is labeled "Fancy". This is a USDA grade, relating to specific gravity. Fancy ketchup has a higher tomato solid concentration than other USDA grades.[35]

Fancy 1.15 33%
Extra Standard 1.13 29%
Standard 1.11 25%

## Composition

Heinz tomato ketchup’s ingredients are: tomato concentrate from red ripe tomatoes, distilled vinegar, high fructose corn syrup, corn syrup, salt, spice, onion powder, and natural flavoring.[36] Tomato concentrate from red ripe tomatoes is the first ingredient on the list, which means it has the highest percentage of weight within the final product. Tomatoes have a complex composition of sugars, starch, pectin, ascorbic acids, organic acids, amino acids, steroids, carotenoids, lipids, free fatty acids, and volatiles.[37] The second ingredient listed is distilled vinegar, which is eighty percent pure water and twenty percent acetic acid.[38] Next is high fructose corn syrup, which is made up of 42% fructose, 53% glucose, and 5% other polysaccharides and sugars.[39] Corn syrup is 100% glucose.[39] Salt is the next ingredient listed and is composed of sodium and chloride ions. Spice, onion powder, and natural flavoring are the last ingredients on the list, meaning that they have the least percent weight. These three ingredients contribute to overall flavor of the product.

## Nutrition

The following table compares the nutritional value of ketchup with raw ripe tomatoes and salsa, based on information from the USDA Food Nutrient Database.[40]

Nutrient
(per 100 g)
Ketchup Low sodium
Ketchup
Tomatoes,
year-round
USDA commodity
salsa
Energy 100 kcal
419 kJ
104 kcal
435 kJ
18 kcal
75 kJ
36 kcal
150 kJ
Water 68.33 g 66.58 g 94.50 g 89.70 g
Protein 1.74 g 1.52 g 0.88 g 1.50 g
Fats 0.49 g 0.36 g 0.20 g 0.20 g
Carbohydrates 25.78 g 27.28 g 3.92 g 7.00 g
Sodium 1110 mg 20 mg 5 mg 430 mg
Vitamin C 15.1 mg 15.1 mg 12.7 mg 4 mg
Lycopene 17.0 mg 19.0 mg 2.6 mg n/a

Ketchup has moderate health benefits.[41] Ketchup is a source of lycopene, an antioxidant which may help prevent some forms of cancer. This is particularly true of the organic brands of ketchup, which have three times as much lycopene.[42] Ketchup, much like marinara sauce and other cooked tomato foods, yields higher levels of lycopene per serving because cooking increases lycopene bioavailability.[citation needed]

## Viscosity

Transferring ketchup between plastic bottles.

Commercial tomato ketchup has an additive, usually xanthan gum, which gives the condiment a pseudoplastic or "shear thinning" property - more commonly known as thixotropic. This increases the viscosity of the ketchup considerably with a relatively small amount added—usually 0.5%—which can make it difficult to pour from a container. However, the shear thinning property of the gum ensures that when a force is applied to the ketchup it will lower the viscosity enabling the sauce to flow. A common method to getting ketchup out of the bottle involves inverting the bottle and shaking it or hitting the bottom with the heel of the hand, which causes the ketchup to flow rapidly. A technique involves inverting the bottle and forcefully tapping its upper neck with two fingers (index and middle finger together). Specifically, with a Heinz ketchup glass bottle, one taps the 57 circle on the neck. This helps the ketchup flow by applying the correct shearing force.[43] These techniques work because of how pseudoplastic fluids behave: their viscosity (resistance to flow) decreases with increasing shear rate. The faster the ketchup is sheared (by shaking or tapping the bottle), the more fluid it becomes. After the shear is removed the ketchup thickens to its original viscosity.

Ketchup is a Non-Newtonian fluid meaning that its viscosity changes under stress and is not constant. It is a shear thinning fluid which means its viscosity decreases with increased shear stress.[44] The equation used to designate a Non-Newtonian fluid is as follows: ${\displaystyle \eta =\tau /{\dot {y}}}$ . This equation represents apparent viscosity where apparent viscosity is the shear stress divided by shear rate. Viscosity is dependent on stress. This is apparent when you shake a bottle of tomato sauce/ketchup so it becomes liquid enough to squirt out. Its viscosity decreased with stress.[45]

Graph representation of the three main fluid viscosity categories

The molecular composition of ketchup is what creates ketchup's pseudoplastic characteristics. Small polysaccharides, sugars, acids, and water make up the majority of the metastable ketchup product, and these small structures are able to move more easily throughout a matrix because of their low mass. While exposed to shear stress, the molecules within the suspension are able to respond quickly and create an alignment within the product.[46] The bonds between the molecules are mostly hydrogen bonds, ionic interactions, and electrostatic interactions, all of which can be broken when subject to stress. Hydrogen bonds are constantly rearranging within a product due to their need to be in the lowest energy state, which further confirms that the bonds between the molecules will be easily disrupted. This alignment only lasts for as long as shear stress is applied. The molecules return to their original disorganized state once the shear stress dissipates.[46]

## Separation

Ketchup is one of the many products that is leachable; meaning that the water within the product migrates together as the larger molecules within the product sediment, ultimately causing water to separate out. This forms a layer of water on top of the ketchup due to the molecular instability within the product.[38] This instability is caused by interactions between hydrophobic molecules and charged molecules within the ketchup suspension.

Pectin is a polysaccharide within tomatoes that has the ability to bind to itself and to other molecules, especially water, around it. This enables it to create a gel-like matrix, dependent on the amount within the solution. Water is a large part of ketchup, due to it being 80% of the composition of distilled vinegar. In order for the water within the ketchup to be at the lowest possible energy state, all of the hydrogen bonds that are able to be made within the matrix must be made.[47] The water bound to the polysaccharide moves more slowly within the matrix, which is unfavorable with respect to entropy.[38] The increased order within the polysaccharide-water complex gives rise to a high-energy state, in which the water will want to be relieved. This concept implies that water will more favorably bind with itself because of the increased disorder between water molecules. This is partially the cause for water leaching out of solution when left undisturbed for a short period of time.

Other interactions that induce leaching are electrostatic and ionic interactions. Electrostatic interactions occur between charged molecules, which have repulsive or attractive forces between each other. The pectin within ketchup will have negative and neutral charges along the molecule due to the hydroxyl groups and relative pH, which is 3.9 on average.[48] Pectin is most stable at a pH of 3.5, so the more basic pH within ketchup will protonate the hydroxyl side chains and therefore create a less viscous gel. Acetic acid within vinegar also has hydroxyl groups that will have a dispersed amount of negative and neutral charges along each molecule. The acetic acid and pectin will display repulsive interactions between the negatively charged oxygens on each molecule. The hydroxyls on each molecule will be able to form hydrogen bonds with the water in the product. The addition of salt will reduce the repulsive interactions between the negatively charged side chains of acetic acid and pectin within solution because they will create bonds with the dissociated sodium and chloride ions.[49] The hydrogen bonds and electrostatic interactions will encourage leaching because the formation of bonds associated with the need for molecules to be in the lowest energy state are not always bonds that happen between different molecules and instead are formed between like molecules, causing aggregation.

A way for ketchup manufacturing companies to avoid leaching of their products would be to add a hydrocolloid. Xanthan gum is able to stabilize ketchup by covalently binding to water. This strong bond keeps water from separating out of the ketchup and creating a layer at the surface.[38]

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