Vinegar

Vinegar

Ubana, A. (Photographer). (2018). Left to right: rice vinegar, coconut vinegar, white vinegar [photograph]. Calgary, Canada

Vinegar is a versatile solution in its many different forms. It can be used in cleaning¹, flavouring ^{2, 3}, pickling food^2,4 and as a preservative¹.  This diluted solution is made up of 95% water and 5% acetic acid. Acetic acid is also called ethanoic acid and glacial acetic acid, the latter is just acetic acid with less water content. The boiling point of acetic acid is 117.9 ℃⁵, however, when combined with water the boiling point is 100.6 ℃⁶. This is interesting but expected because vinegar is mostly water therefore the boiling point would be closer to that of water. 

Surprisingly, making vinegar involves the fermentation of yeast. Fermentation is just breaking down a substance that contains sugar into an alcohol. Alcohol is then broken down by the microorganism, Acetobacter, to make the vinegar². This process is done in many various ways, however, the most common is tfhe submerged process⁷. This process works by pouring alcohol into a tank from the top where the bacteria is allowed to break down this liquid⁸. Meanwhile, a stirrer at the bottom creates air bubbles which speeds up the process². This method is the best because it provides the highest concentration of acetic acid in the vinegar². Some items that can be broken down in the entire process is alcohol, rice, apples, coconuts and more⁹.

What’s interesting about vinegar is that it is actually made by an organism, yet it’s used to clean and kill other bacteria. Another interesting fact is that the Ancient Romans used ‘sugar of lead’, aka sapa, to sweeten their food and wine¹⁰. Sapa is a mix of lead and acetic acid. This sweetener was frequently used and it was thought to be a factor in the fall of the Roman Empire due to lead poisoning. Another interesting use of vinegar is to clean jellyfish wounds¹¹. A study found that vinegar stops the release of the poison from the tentacles. However, they found that it was also able to produce more poison. A different group of researchers said that this study was wrong because their math was incorrect and the production of more poison was not significant¹². Overall, vinegar is an all-purpose solution. It’s a great way to add flavour to food or to aid in cleaning. 



References

1.     Budak, N.H.; Aykin, E.; Seydim, A.C.; Greene, A.K.; Guzel-Seydim, Z.B. Functional properties of vinegar. J Food Sci. 2014, 79(5), 757-764.doi: 10.1111/1750-3841.12434. (accessed Dec 1, 2018)  

2.     Bamforth, C.W. Vinegar. In Food, fermentation and micro-organisms, Bamforth, C.W, Eds.; Blackwell: Oxford, 2005; pp. 154-159

3.     Joachim, D.; Schoss, A. The science of vinegar. https://www.finecooking.com/article/the-science-of-vinegar (accessed Dec 1, 2018)

4.     Bonem, M.  The science of vinegar pickling, explained. https://www.foodandwine.com/vegetables/pickled- vegetables/science-vinegar-pickles-explained (accessed Dec 1, 2018)

5.     Acetic Acid. https://pubchem.ncbi.nlm.nih.gov/compound/acetic_acid#section=Odor (accessed Nov 27, 2018)

6.     Tom. Boiling point of vinegar. https://van.physics.illinois.edu/qa/listing.php?id=1456 (accessed Dec 1, 2018)

7.     Vinegar. Encyclopedia of American Food and Drink [Online]; Bloomsbury: London, https://search-credoreference-com.libproxy.mtroyal.ca/content/entry/bloomfood/vinegar/0 (accessed Dec 1, 2018)

8.     Bhat, S. V.; Akhtar, R.; Amin, T. An overview on the biological production of vinegar. Inter. J. of Ferm. Foods. 2014, 3(2), 139-155. DOI No. 10.5958/2321-712X.2014.01315.5 (accessed Dec 1, 2018)

9.     Allema, G.A. Ultimate guide to vinegar. https://recipes.howstuffworks.com/how-vinegar-works1.html (accessed Dec 9, 2018)

10.  Rhodes, J. “Sugar of lead: A deadly sweetener”.  https://www.smithsonianmag.com/arts-culture/sugar-of-lead-a-deadly-sweetener-89984487/ (accessed Dec 3, 2018)

11.  “Box jellyfish stings: to vinegar or not?” Https://www.resus.com.au/2015/02/22/box-jellyfish-stings-to-vinegar-or-not-to-vinegar/ (accessed Dec 2, 2018)

12.  Yanagihara, A.A; Chen, J.J. The effect of vinegar on discharged nematocysts of Chironex fleckeri. Diving Hyperb. Med. 2014, 44(3). 172, https://www.ncbi.nlm.nih.gov/pmc/articles /PMC5487263/(accessed Dec 2, 2018)