ICHEM Postlab Ketchup

8/4/2019 ICHEM Postlab Ketchup

http://slidepdf.com/reader/full/ichem-postlab-ketchup 1/4

Experiment No. 8

KETCHUP MAKING

QUINTO, Joanna G.

Department of Chemical Engineering, Faculty of Engineering

University of Santo Tomas

España, Manila

Abstract

In the conducted experiment, ketchup was made using tomato as the

main raw material. White vinegar, onion, garlic, celery, cornstarch, hot pepper

and sugar were also used in the experiment. The produced ketchup was then

tested in terms of its texture, odour, colour, taste and viscosity. The texture was

smooth and thick, the odour is the same of that a tomato, colour is partly in-

between orange and red, the taste was moderately the same of a tomato only

with a tinge of saltiness, sweetness and spiciness. The ketchup made was highly

viscous.

I. INTRODUCTION

The ketchup is one of the most commonly used condiments which

is primarily made from tomatoes. It is often used together with a variety of

foods like french fries, hamburgers, sandwiches, meat and many more. It is a

sweet-and-tangy condiment typically made from tomatoes, vinegar, sugar or

high-fructose corn syrup, and an assortment of vegetable seasonings and

spices such as onions, allspice, cloves, cinnamon, garlic, and celery.1 It is

sometimes spelled as catsup in American English and Canadian English.

Indonesian and Asian culture invented what we know today as

ketchup. The spicy, pickled fish sauce made of anchovies, walnuts,

mushrooms and kidney beans, dating back thousands of years were called

ke-tsiap or kecap and were popular in 17th-century China. British seamen

brought ke-tsiap home with them where the name was changed to catchup

and then finally ketchup. It wasn't until the late 1700s though that canny New

Englanders added tomatoes to the blend.2 Henry J. Heinz began making

ketchup in 1876 but he was neither the inventor nor the first to bottle it. His

recipe remains the same to this day.2 Because ketchup is mainly made from

tomatoes, it is said to be a source of lycopene, a carotenoid that functions as

an antioxidant and gives the red colour to tomatoes, watermelon, and red

grapefruit. It is also an antioxidant which may help prevent some forms of



cancer.1 Tomatoes are also rich in food components necessary for the

normal growth of human such as carotenoids (lycopene), ascorbic acid

(vitamin C), vitamin E, folate and dietary fibre.4

Tomato ketchup has a high acid content due to both the tomatoes

and vinegar in it and therefore does not require refrigeration after opening. It

is safe to store at room temperature, but it will taste better if refrigerated.3

Although the acidity of ketchup preserves the sauce, manufacturers

recommend that once containers are opened they should be refrigerated to

prevent deterioration of the ketchup color, flavor, and quality.

II. METHODOLOGY

A. Chemicals and Reagents

The raw materials used namely the tomato, white vinegar, salt,

sugar, hot pepper, onion, garlic, celery and cornstarch were provided

individually by each group as well as the casseroles that were used. The

stockroom provided for the thermometers and the hot plate that were

used by each group.

B. Experimental section

One kilogram of tomatoes was washed. It was then blanched with

boiling water and cut into quarters. The skin of the tomatoes was peeled

off. The tomatoes were boiled with one sliced onion and hot pepper in 20

mL of water. The number of hot pepper added was optional. The mixture

was macerated and then, the juice was extracted using the strainer. 150

mL of vinegar as well as the other ingridients (celery, garlic) was boiled all

together for 15 minutes and then it was strained. The tomato juice was

boiled with 100-150 grams of sugar. The tomato juice was simmered untilonly ½ of the original volume remained. The vinegar solution was then

added to the tomato juice and it was simmered until desired consistency

was achieved. Salt was added in order to somehow adjust to the desired

taste. Two tablespoons of starch dissolved in 10 ml of water was added to

the mixture and was mixed for two to three minutes. In attaining the



desired consistency of the ketchup, the ketchup was tranferred into a

sterile bottle. It was then pasteurized at 60-100ºC for 15 minutes.

III. RESULTS AND DISCUSSION

The final ketchup made was observed to have the following

characteristics (please refer to table III-1).

Texture Smooth and thick

Odour Tomato, partly vinegar, other spices

Colour Reddish orange

TasteSpicy, partly sweet, has an apparent

tomato taste

Viscosity Highly viscous

Table III-1. Analysis of he tomato ketchup produced

Based on the table presented above, the texture of the ketchup

produced by the group is smooth and thick. The cornstarch acts as the

thickening-agent in the experiment. The thickening –agent acts as water-

binding materials, which hold water and prevent moisture removal during the

cooking process. Thus the addition of thickening agents increased the

consistency of ketchup, because the moisture did not vaporize easily.4 The

odour was the same as that of the tomato with a slight odour of the vinegar

and of the spices that were added. The colour of the produced ketchup was

reddish orange. The produced ketchup did not fully acquire the colour of the

tomatoes. This might be because of the vinegar and the water added and

because some of the juices of the tomato were disposed during the peeling

process. Because tomatoes undergo oxidation, the ketchup may also

undergo oxidation as well. Oxidation of ketchup can darken the color of

ketchup, but de-aeration of the sauce during manufacture can prevent this

problem. However, once the containers are opened, oxidation may still occur.



Fortunately, the produced ketchup did not undergo much oxidation and the

reddish-orange color of the tomato was retained. The taste of the produced

ketchup was spicy due to the added chili. Apparently, the ketchup has the

taste of the tomatoes. The consistency of the tomato was highly viscous. This

is caused by the thickening-agent which increases the viscosity of the mixture

withour altering much of its other properties.

IV. CONCLUSION

Based on the results obtained from the conducted experiement, the

produced ketchup is acceptable. The texture, odor, color, taste and

consistency of the produced ketchup are satisfactory however, because of

some complications in the performed experiment, like inaccurate

measurements, human errors and certain chemical reactions, the desired

characteristics were not fully achieved.

V. REFERENCES

1. Ketchup. Retrieved from http://en.wikipedia.org/wiki/Ketchup

2. Kerrigan, L. (2001). Everything You Always Wanted to Know

About Ketchup (Catsup). http://www.globalgourmet.com/food/sleuth/0799/

#axzz0kujKjRHo.

3. All You ever needed or wanted to know about Ketchup. Retrieved from

http://nowthatsnifty.blogspot.com/2009/11/all-you-ever-needed-or-

wanted-to-know.html

4. Ahmed, M., Akter, S.M., Alam, M.K., Islam, N., & Jong-Bang, E. (2009).

Effect of Carboxymethylcellulose and Starch as Thickening Agents on the

Quality of Tomato Ketchup. Retrieved from http://www.pjbs.org/pjnonline/

fin1349.pdf.

ICHEM Postlab Ketchup

Documents

Transcript of ICHEM Postlab Ketchup