Glass vs. Plastic Bottles: Which is the Best for Beverage Packaging?

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It takes a few seconds to form a first impression about a stranger, while it takes less than that for a consumer to evaluate your product amongst others on the market. In most cases, these decisions are made without looking at the labels and descriptions of the product. Just as how it is with judging a book by its cover, but in this case, it’s judging the product by its packaging.

The kind of packaging used plays a big role in determining how fast a product will be sold. Glass and plastic packaging make up the vast majority of containers used for beverages. Choosing the right material to use between these two options for your beverage bottles is an important decision that should be made with in-depth knowledge of their characteristics and how beneficial they are to your product.

To help you with this, we will be discussing all you need to know in this post.

Glass Beverage Packaging

Glass Drink Bottles
Source: Roetell

These are the facts you need to know about glass beverage packaging.

Materials

Glass is made from natural raw materials that are composed of high-quality properties. These materials include liquefied sand, soda ash, recycled glass, limestone, and other additives. They are melted at high temperatures to form a new material – glass.

Amongst these materials, limestone stands out. It helps in preventing the glass from weathering, which is why it’s mostly used in glass bottle production. However, it has a disadvantage on the environment. Limestone mining is dangerous to the environment as it causes water pollution, noise pollution, development of sinkholes, amongst others. It can cause permanent damage to the landscape, as well as to the animal habitats in limestone caves.

Manufacturing Process

Glass Bottle Manufacturing Factory
Source: Roetell

Two processes can be followed to make glass bottles – the “Press and Blow Process” and the “Blow and Blow Process.” The raw materials are combined into a specific mixture based on the intended characteristics of the bottle. After this, the mixture is melted at a high temperature in the furnace until it liquefies into a molten glass ready for formation.

Using the Press and Blow process, a shearing blade is used to cut the molten glass into a predetermined gob size. The gob is pushed into the mold using a metal plunger. In the mold, it starts taking shape and turns into a parison, which is then moved into the blow mold and reheated until it’s soft enough to complete the dimensions of the glass. After the parison has been reheated to blowing temperature, the air is blown into the container to form the desired shape.

The Blow and Blow process also requires that the molten glass is cut into the desired gob size and fed into the mold. But here, the parison is obtained by using compressed air to form the bottle shape and the neck finish. After this, the parison is flipped 180o and heated again before the air is injected to blow the container into its appropriate shape. The Blow and Blow process is ideal for making glass bottles with various neck thicknesses.

Regardless of the method used, once the bottle is completely formed, it’s taken out of the mold and moved to the annealing lehr. In the lehr, the bottle is reheated to a temperature of about 1050o Fahrenheit before being gradually cooled to about 390o Fahrenheit. This finishing process allows the glass to cool at an even rate, thereby removing internal stresses that could lead to cracking or breaking.

Transportation

Glass bottles are at a disadvantage when it comes to transportation. A lot of resources, including cost and energy are spent on moving glass bottles. This is because they are fragile and usually heavy. To ensure that they do not break during transportation, inserts and other supportive objects are used to hold them in place.

While empty glass bottles are heavy, they become heavier when they are filled with products. Even beverages and sparkling water glass bottles have more weight and become more fragile, meaning that they must be protected all through traveling. This in turn, has an effect on the speed of delivery, as well as the amount of fuel and air pollution that will be emitted from the car exhaust.

In certain cases, some staff will need to be assigned to the back of the car where the glass bottles are kept to ensure that the support system is intact. If all these protective measures are not put in place, the glass bottles might break, resulting in a fresh production start.

All this means for a business trying to procure glass beverage bottles is that the shipping cost is expensive, which means your total cost will be increased.

Recyclability

According to the Glass Packaging Institute (GPI), glass is 100% recyclable, which means that for each time a glass is recycled, the resulting product does not reduce in quality or purity. In fact, most glass manufacturers make use of salvaged glass bottles to make new ones. In some cases, the already used bottles are mixed with other raw materials to manufacture bottles with specific quality standards and colors.

The benefits of glass bottles’ recyclability extend to the manufacturing process as lesser energy will be used. The furnace temperature will be reduced because the recycled glass has already been melted appropriately.

Also, glass can be washed, sterilized, and re-used for either the same or different applications. If the glass bottle formerly contains beverages, after exhausting the product, it can be washed and used to store other products, like cosmetics, fuel, chemicals, etc.

Cost

Besides the fact that glass is very expensive to ship, it also costs a lot to produce and this is due to the amount of heat used for production. Glass manufacturing is energy-intensive, accounting for a reasonable amount of the total industrial energy used. For the glass materials to be properly melted, they are put under a very high temperature.

Plastic Beverage Packaging

Plastic Bottles
Source: Unsplash 

These are the facts you need to know about plastic beverage packaging.

Materials

The materials used in making plastic beverage packaging are Polyethylene Terephthalate (PET), Polypropylene (PP), High Density Polyethylene (HDPE), Low Density Polyethylene (LDPE).

Polyethylene Terephthalate (PET) is the major plastic used in making plastic beverage packaging. Its usage extends to other industries like pharmaceuticals and personal care industries. PET is a strong and lightweight form of polymer primarily gotten from petroleum hydrocarbons and is the end product of a reaction between ethylene glycol and terephthalic acid.

Manufacturing Process

There are three basic manufacturing processes used in making plastic beverage packaging. They are Extrusion Blow Molding (EBM), Injection Blow Molding (IBM), and Stretch Blow Molding (SBM). They are explained in the next series of paragraphs.

In Extrusion Blow Molding (EBM), an extruder creates a hollow, round tube or parison. The parison is enclosed by a mold cavity with two halves that pinches off one end. The parison is then expanded with compressed air to conform against the cold mold cavity walls. When completely cool, the mold opens, allowing for the removal of the container and trimming of any flash. This process significantly reduces bottle weight and cost while increasing performance.

Injection Blow Molding (IBM), which is the second process, is used for the manufacturing of hollow plastic bottles. The process is performed in three main stages. At the first stage, the molten plastic is fed into the mold cavity to create a preformed parison. The preform looks like a test tube, while the top has a molded screw finish. In the second stage, the air is blown through a core pin to expand the preform against the mold cavity. The bottle is then moved to the third station where it will be ejected.

The third process which is Stretch Blow Molding (SBM), uses either the EMB or IBM process and has a basic foundation. In either scenario, a perform parison is molded and transferred to a blow molding chamber. At the blow molding stage, the parison is biaxially stretched to align and orient the molecules. The SBM process improves the gas barrier, clarity, rigidity, and impact strength of the bottle.

Transportation

Plastic bottles are lightweight and durable, making them very easy to transport. Since they are not heavy and don’t break easily, they can be moved around in any condition, even on bad roads. Also, since they are lightweight, the amount of fuel needed to transport them is low, hence reducing the total cost.

Unlike glass soda bottles which require a lot of resources in ensuring that they are safely delivered, plastic soda bottles do not require many resources. As long as the plastic bottles are properly arranged, there is no need for any support system to hold them in place.

This helps to lower the total cost that’s involved in using plastic bottles for your beverage brand.

Recyclability

Plastic Bottles Recycling
Source: Unsplash 

Most plastic bottles can be recycled, but they degrade with time. That is, the quality and purity you’ll get won’t be like the first product. Also, even though plastic bottles are commonly washed, sterilized, and re-used, they tend to degrade over time. This is very evident when the former products contained in the plastic bottles are things like oils, chemicals, and cosmetics. No matter how many times they are washed, they cannot go back to their former state.

This is why most times, plastic bottles are recycled into other materials like synthetic clothing or carpets. This process is called “downcycling.”

Due to the conditions affecting the recyclability of plastic bottles, they are usually thrown away immediately after usage, which is why they constitute a large percent of the total garbage in landfills.

Cost

Plastic bottles are cost-effective. Not only are they inexpensive to ship, but they are also cheap to manufacture as less energy is used. With new technology in plastic molding, the production of plastic bottles has become more affordable. In fact, it is arguable that producing new plastic is cheaper than recycling it.

Glass Bottle vs. Plastic Bottle

Cola Glass Bottle vs. Plastic Bottle
Source: Unsplash 

Having known the characteristics of glass and plastic packaging, let’s do justice to the differences between them – glass bottles vs. plastic bottles.

Pros of Glass Bottles

  • Aesthetics: Glass offers a premium experience in appearance, feel, and weight, which makes customers put any product contained inside in their preference list. The aesthetic benefits of glass bottles are primarily used by businesses to promote any product that needs to have a sophisticated image for marketing. Some of the products that fall into this category are luxury fruit juices and craft cold brew.
  • Recyclability: Glass bottles are 100% recyclable. No matter the product put in them, they can be reused countless times without the glass degrading in quality and purity. Also, as an advancement to make other quality standards and color variations, all that’s to be added are some other raw materials.
  • Chemical-resistant: Glass has intrinsic properties that offer inertness and impermeability needed for sensitive products. This extends to liquids that are to be stored for a long period of time, such as spirits and other alcoholic beverages. Also, they are strong enough to withstand a wide range of temperatures; they won’t warp under pasteurization.
  • Non-toxic: Glass is not hazardous; it contains no substances that could be dangerous and generally has no bad effects on human health. Compared to plastic, it is less porous. Also, it is highly resistant to leaching into your products even when kept for a long period of time. As the public keeps on learning about bisphenol A (BPA) and other potentially toxic compounds in plastics, manufacturers of beverages and other natural products should start switching to glass.

Cons of Glass Bottles

  • Production cost: Glass is energy-intensive, meaning that a lot of heat is used in production. For glass to be melted to the proper molten state, a high temperature is used. This means that there will be an increase in production to get adequate energy (natural gas) to do this.
  • Transportation cost: The cost of shipping glass bottles is more than plastic bottles. This is because glass has more weight and is more fragile, so caution must be taken to prevent cracks. While a glass bottle of 2 fl. oz weighs about 0.177 lbs, its plastic bottle counterpart may weigh only 0.023 lbs. While the difference may seem little with a single bottle, consider shipping in bulk.
  • Breakage: A common drawback attributed to glass products, including glass bottles is breakage. They must be handled with care at all times. This means that a reasonable amount of caution must be taken when using glass bottles so that they don’t break. It could be dangerous if you gave a little child to hold as he/she could drop it mistakenly. Another thing that causes breakage is its slipperiness. And this is worse with people who have sweaty hands.

Pros of Plastic Bottles

  • Durability & ease of use: A salient benefit of plastic bottles is durability and ease of use. They are very strong and no matter how many times they fall, they won’t break. Also, they can be fabricated to have necks where the finger can be inserted for better grip.
  • Production cost: When compared to glass, the melting point of plastic is much lower. Hence, less energy is used in production. In addition to this, the plastic manufacturing industry benefits from new technology developments as more advanced techniques and machinery are used in plastic molding, thereby reducing production costs.
  • Transportation cost: Generally, plastic is lightweight and durable, making it much more suitable for shipping than glass. During transportation, 100% focus is not needed on the plastic bottles as they don’t break easily. Unlike glass bottles, they can break from colliding with each other.

Cons of Plastic Bottles

  • Aesthetics: As much as aesthetics is concerned in plastic bottles vs. glass bottles, the former is second in line. Even though plastic bottles can be fabricated to have beautiful geometries and feel, more can be done to glass bottles. Glass bottles are more suitable for high-end positioning brands.
  • Recyclability: The resulting product after recycling is generally below par. While glass bottles are100% recyclable, plastic bottles, when recycled, don’t produce the same quality and purity as the original product.
  • Less resistance to chemicals: Plastics are less resistant to chemicals. They can’t withstand harsh conditions and chemicals. Also, some of them are not resistant to temperature, including UV rays.
  • Toxicity: While some plastics don’t contain BPA, they all have a bad reputation for their toxicity and tendency to leech into products. When not correctly used, they can possibly leach harmful chemicals into your products. Glass bottles are highly preferred in this regard.

Here’s a concise summary in a tabular form.

Glass BottlesPlastic Bottles
Better aestheticsLesser aesthetics
100% recyclabilityLow quality and purity recycling
Highly resistant to chemicalsLow resistance to chemicals
Not harmful to the human healthHarmful to the human health
High production costLow production cost
High transportation costLow transportation cost
Easily breakableExtremely durable

How to Choose the Right Packaging for Your Beverage Business

Beverage Bottles in the Factory
Source: Unsplash 

While both glass and plastic packaging have their merits and demerits, choosing the right packaging for your beverage business is dependent on some factors. They are highlighted below.

Product Packaging Needs

The first factor to consider is what works best for your product. If it’s a spirited beverage that needs to be stored for a long time, the best option to consider is glass bottles. On the other hand, if it’s a product mainly consumed by children, then the best packaging is plastic bottles given the fact that plastic bottles are easier to handle and they won’t break. Also, children will most likely prefer to press the bottle to squeeze out all the content, and this can only be done with a plastic bottle.

So basically, what you have to prioritize is the type of product that’s to be packaged, how the packaging affects the quality of the product, how convenient is the package for the intended consumers, etc. If the package is aesthetically excellent but doesn’t favor the consumers, your product will spend years on the shelf. Nobody wants a liability.

Budget

While satisfying the consumers and providing them with a package that fits the products and meets their needs, you should remember that you are running a business. And businesses are meant for profit-making, so when choosing the best package for your product, consider the total cost of production. How much do the raw materials cost? How much are the production expenses? Have a list of all the expenses you’ll incur.

As highlighted in the glass bottle vs. plastic bottle differences section above, glass bottles are more beautiful to behold, but they have a higher production cost when compared to plastic bottles. So, be sure that you have the money to spend on acquiring glass bottles. If you don’t, then you can give plastic bottles a shot.

Transportation

Just like the production cost, glass bottles are more expensive when it comes to transportation. Glass bottles are heavy and fragile, which means that utmost care must be taken when shipping them. Unlike plastic bottles, they are lightweight and strong. No matter how many times they fall, they don’t break.

Also, glass bottle transportation consumes more gas or fuel. Since they are heavy, the car will consume more energy compared to the energy that will be consumed in moving lightweight objects like plastics.

All these have an effect on the total cost of transportation. Shipping glass bottles are more expensive than plastic bottles. So, the decision is left to you. Do you have sufficient funds to cater for glass bottle transportation? If you do, fine. But if you don’t, the alternative option is plastic bottles.

Glass Bottle vs. Plastic Bottle and the Environment

Bottles and environmental protection
Source: Freepik

While every factor is being considered, you shouldn’t forget to look into how the packaging affects the environment. Is it eco-friendly?

As earlier stated, glass bottles are 100% recyclable, meaning that they’re eco-friendly. On the other hand, plastic bottles are not 100% recyclable. This means that while landfills are filled with more plastic bottles, glass bottles are less.

Moreover, using glass bottles helps to lower your total cost, as salvaged glass bottles can be used to make new ones. In fact, they can be modified to the quality standard or color you want. But the same can’t be said about plastic bottles. They depreciate after their first use, making them less reliable and constituting more waste to the environment.

Conclusion

Having examined the characteristics and differences between glass and plastic packaging, the final decision on which is best can only be made by you. How do these two packaging types affect your business? Considering all the benefits and drawbacks they both possess, which is best for your brand?

To place orders on your plastic bottles, there are several reliable manufacturers on the market, and for your glass bottles, you can contact Roetell for the best and strongest packaging.

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