They are all Coke. The one in the glass bottle is considered a masterpiece, but the one in the plastic bottle... why is it so unpalatable?

There is no summer that doesn't need to be saved by an ice-cold Coke.

When it comes to the small issue of "drinking Coke", many people have their own little habits. For example, some people only prefer a certain brand (the red-blue battle), while others are particularly picky about the containers for Coke and are unwilling to drink Coke in plastic bottles.

It is easy to understand how to choose a cola brand, but what about choosing the container to hold the cola?

It turns out that many people think that cola in different packaging tastes different, and cola in plastic bottles does not taste as good as that in glass bottles.

Which type of cola packaging is better? Image source: Weibo

How does packaging affect taste?

Why does the same cola taste different when packaged differently? Is there a difference in the ingredients of cola in different packages?

In fact, it isn't. In response to the questions raised by cola lovers, a large cola company specifically explained the taste of cola. No matter whether it is packaged in glass bottles, plastic bottles, or cans, all colas are the same, with no difference from the formula to the production process.

Officials claim that there is no difference between different packaging of Coke, image source: coca-cola.co.uk

However, the company also admitted that the taste of Coke is affected by many factors, such as temperature and packaging, which can affect the carbonation content.

Have you ever noticed that iced cola is more carbonated? Carbon dioxide, the soul of cola, dissolves in water to form carbonic acid (H2CO3). When the temperature drops, the solubility of carbon dioxide increases, fully stimulating the taste receptors, making it more carbonated and giving the tip of your tongue a wonderful sweet and numbing experience.

The reason why packaging affects taste may be that different packaging has different degrees of air leakage.

Currently, the three common types of cola on the market are plastic bottles, cans and glass bottles.

Coke in different packages, image source: popsci

1. The glass bottle has good airtightness and sufficient carbon dioxide

The earliest cola was produced in glass bottles. The main component of glass is silicon dioxide, which is very stable in chemical properties and will hardly react with the substances it contains. In addition, the glass bottle is very airtight, so the carbon dioxide filled in it is not easy to escape.

So, when you drink cola from a glass bottle, especially when you take a gulp of ice cola, the joy of the rich carbon dioxide gas running through your mouth is unmatched by any other beverage. This is the refreshing experience that can only be created by sufficient carbonation.

Glass bottles used to hold Coca-cola, image source: coca-colacompany

2. Can coating affects the taste

Currently, Coke in cans and plastic bottles is more common than in glass bottles.

The material used to make cans is mostly aluminum, which is a relatively active metal with unstable chemical properties. In order to prevent it from coming into contact with the ingredients in cola and reacting, a special coating (epoxy resin) is placed on the inner wall of the can. Its properties are very stable and can separate the metal from the cola, while preventing oxygen from entering the can and affecting the ingredients of the beverage.

3. Plastic bottles are not airtight enough, and carbon dioxide is easily lost

As for the often-disdained plastic bottles, their main component is polyethylene terephthalate, also known as PET.

The disadvantages and advantages of plastic bottles are very prominent. On the one hand, they are light and not easy to break. On the other hand, their airtightness is not as good as cans and glass products. Especially when the temperature is high or exposed to direct sunlight, the loss of carbon dioxide in the bottle will increase significantly.

At present, the use of plastic bottles is becoming more and more widespread. Take Coca-Cola as an example. PET materials account for almost 45% of its product packaging. No wonder most of the cola in supermarkets is packaged in plastic bottles.

About 45% of Coca-Cola's packaging uses PET materials. Image source: statista

How can you drink the “most authentic” Coke?

As most people think, cola in glass bottles is least affected by the outer packaging and can best maintain its original flavor. However, considering that transparent glass bottles have poor light protection, it is best to drink the cola you buy in glass bottles as soon as possible or store it away from light.

Canned cola tastes good too. Compared with glass bottles, cans are better at keeping out light and cool quickly in the refrigerator, so you can get iced cola quickly. As for some people who think that canned cola has a metallic taste, it is probably because these people are particularly sensitive to metals. When they drink canned cola, they first come into contact with the metal packaging, so they taste the metallic taste.

If you want to choose cola in plastic bottles, you should choose the ones with the latest production date and drink them as soon as possible. In particular, you must be careful when choosing large-package cola, because if you can't finish it all at once, the carbon dioxide in it will soon be lost, and the taste of the cola will be greatly reduced. In addition, leaving it open for a long time will cause microorganisms to multiply and affect your health.

In addition, remember that someone commented earlier that McDonald's Coke tastes the best? This is because the Coke in fast food restaurants is freshly made and the carbon dioxide in the Coke is also freshly charged, so there is no loss and the taste is naturally better.

Although many people with sensitive taste buds can taste the difference between cola in different packages, most people don't actually care about such subtle differences.

After all, compared with the bizarre flavors launched by various cola brands (such as Coca-Cola's cherry-flavored cola), the difference in taste caused by different packaging is really minimal.

Cherry Cola

Cherry Cola? Don’t I deserve a name? Image source: Wikipedia

References

[1] Li Xianzhong. New understanding of the determination of carbon dioxide content in carbonated beverages [J]. Journal of Beijing Institute of Light Industry, 1991(01):55-62.

[2] Zhu Danqian, Weng Feifei. Overview of Carbonated Beverage Packaging Materials[J]. Modern Food, 2016(10):56-57.

[3]Chandrashekar J, Yarmolinsky D, von Buchholtz L, et al. The taste of carbonation. Science. 2009;326(5951):443-445.

END

Audit expert: Wang Guoyi, Postdoctoral Fellow in Food Safety

Tadpole Musical Notation original article, please indicate the source when reprinting

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