Sodium Hydroxide(Caustic Soda) in Food Production Sodium Hydroxide in Food Production
Lye, the traditional name of sodium hydroxide, is not well known in this modern world of chemical names. Quite like how nobody asks you for a glass of ‘Hydrogen dioxide’ and simply say ‘water’, sodium hydroxide remains the shy alter-ego to lye.
Sodium hydroxide, also known as Caustic Soda, has been known in the world of food additives for over centuries now. It is an integral part of Chinese cuisine where they use it in the form of ‘lye water’. The alkalinity of this chemical can be cleverly incorporated into our food to make it more appetizing. So, the next time you are frying onion rings, try tossing some lye water into the pan and let the magic begin.
Knowing a little bit of chemistry to demystify this marvelous chemical does not hurt at all. After all, we should know what goes into our food.
The lye water which we use in our food is nothing but a very dilute solution of food grade sodium hydroxide. Sodium hydroxide is the strongest alkali known to mankind. It is an ionic compound with sodium acting as the positively charged ion and hydroxide as the negatively charged one.
Lye water is usually stored in glass bottles or plastic containers-a sight very common in the supermarkets, mostly because it is very dilute. Never make the mistake of storing concentrated solutions in glass bottles. It can react with the silicates present in the glass, hence corroding it. However pure solid sodium hydroxide, produced in the form of pellets or flakes, can be stored in plastic containers.
sodium hydroxide pellets
The first thing that pops into our mind, when someone mentions sodium hydroxide is ‘extremely corrosive’. There is no denying this fact, but hey, do not judge a book by its cover. It is perfectly safe as long as it is within the permissible exposure level (PEL) i.e. 2 mg per cubic meter. So, how do you like your food, with or without Sodium Hydroxide? Before you say ‘without!’, think again! Let us see how this remarkable chemical makes our food yummier!
Nobody knows who exactly discovered this frozen delight, but we most definitely cannot thank the person enough. From midnight cravings to flunking in math, ice cream has been the perfect food partner, bringing joy into our lives.
Well, ice cream would have still been in the ‘milkshake zone’ if it was not for sodium hydroxide. Carrageenan, a gelling substance obtained from seaweeds, is used in the thickening of ice cream. When treated with sodium hydroxide, its gel strength increases, and thus helps in getting the consistency of the ice cream just right, making you relish every bite of it!
What if someone asked you to choose between ice-creams and chocolates? You would probably ignore that someone and has both!
Now, can you imagine a world without chocolates or chocolate flavored ice creams or chocolate cakes? We are guessing the answer is a ‘no’. Get ready to be indebted to this wonderful chemical for introducing the world to pure chocolate bliss!
The Dutch process, which forms the basis of modern chocolates, uses sodium hydroxide to reduce the acidity of cocoa. This cocoa, when used in chocolates, gives it an enhanced color and milder taste when compared to that made from natural cocoa. It also enriches the texture of the chocolate, making it smooth and creamy. This ‘Dutched-chocolate’ enjoys its use in baking, hot chocolate, and ice creams.
caustic soda in food production
If you think the job of a chemist is to research, develop, and discover, then you are probably underestimating that person. A chemist can be a great cook too. Haven’t you tasted Walter White’s pancakes? They are delicious!
When was the last time you had a nice, crispy pretzel with golden-brown crust and a rich aroma? The secret ingredient, which gives that pretzel a golden hue and crispiness, is nothing but lye water. Sodium hydroxide reacts with the protein present in the dough, breaking it into amino acids, which in turn reacts with the sugar to form the glossy brown crust, thus making it as crispy as ever. This process, in the world of chemistry, is known as the Maillard reaction. This baking process neutralizes the lye, making it safe for consumption.
The name could be a misnomer as ‘century-eggs’ are nothing related to fossils or real eggs stored for centuries. You can see plastic crates full of these eggs or their dishes, being sold at any Chinese market.
A ‘century egg’ or ‘1000-year egg’ or ‘millennium egg’ is a Chinese delicacy traditionally prepared by preserving duck or chicken eggs in a mixture of clay, ash, and quicklime and leaving it to petrify (No Basilisk, please!) for weeks or months. Modernization, with increased knowledge of chemistry, has simplified the ingredients, from ash to sodium hydroxide. The leavening process increases the PH and sodium content. The result is a century egg, with much higher protein content and lower carbohydrates than fresh eggs!
caustic soda in food production
Would you believe us if we told you olives could taste better than they already do? Others most definitely can.
Curing olives in water or brine solution has been known to enhance the taste of olives. Lye cured olives, are apparently even better!
Oleuropein is the main phenolic compound in olives, giving them a bitter taste. The alkaline solution is soaked through the skin of olives, which then breaks the bonds of the oleuropein molecules, thus relieving it of its nasty bitterness.
Sodium hydroxide softens the flesh in the process, and so make sure your olives are fresh and of the green variety. This way you will not end up with real soggy ones. After the curing process, they are washed thoroughly to get rid of the chemical. And that is how your delicious creamy olives are made ready to eat!
If you are one of those people, who would prefer not to eat fruit over peeling it, then you have come to the right place. Fruits are peeled off their skin using sodium hydroxide, of course.
Effective peeling basically pertains to removing the outer covering of a fruit or vegetable without compromising its nutritional value, and this can be well achieved by treating it with sodium hydroxide. It attacks and hydrolytically degrades the outer skin of the fruit or vegetable and also prevents enzymatic browning. The Canning industry uses caustic soda for this purpose.