Semiotics Case Study: Bread Bags (Part 2 of 2)

This is part 2 of my semiotics case study. Read part 1 here

Problem Identification

As seen in part 1 of my post, the existing bread bags are not very effective in usage and function. What I want to achieve for this project is to create a reusable bread bag that has as many functions as possible.

Demographic of Users

The market segment that I am interested in are the people who care about the environment and want to support small, local businesses. To reach this demographic, I believe that my bags should be sold and promoted by the bakeries that also align with the shoppers’ values.

I believe that the future of grocery shopping, including bread, will have less packaging. Having no packaging is actually the most effective way at displaying the bread. Similar to the deli section, baked goods should all be sold behind a counter.


Shoppers will have the option of using their bag, similar to how you can bring a reusable mug to a coffee shop. When shoppers bring their reusable bread bags, it actually supports the bakery because not having packaging lowers costs and increases profit margin. Furthermore, shoppers get to choose the colour and design of their reusable bag so they are more likely to continue using it in the future.

Exploration / Conceptualisation

I compile a list of functions for the ideal bread bag based on the research of existing bags.

  • Easy to clean, reusable
  • Protection from contamination and moisture
  • Some moisture wicking
  • Visibility of contents
  • Easy to carry to and from the store

After some sketches, I came up with the concept that would best satisfy all the requirements of an ideal bread bag:bag3

Prototyping and Testing

My first thought when it came to reusable bags was that they should be make of cloth. Fabric such as cotton would be very easy to wash. I was able to get a loaf of bread from the bakery put in to the bag. The fit was very good, so the dimensions will be kept for future prototypes. The bag was difficult to carry, so I had to consider adding a handle of some kind.

I have also previously dabbed at making a baguette bag, but it didn’t turn out as I had expected. The bag dimensions were fine – it fit 2 baguettes. The strap was not adjustable, and was sewn in at one side. This caused the bag to sag and sway around in the wind.

The main problem I had with these cotton bags was mold. Despite being breathable, the bread sample left in the cloth bags started to mold, and the mold spread to the cotton bag. The bags had to be soaked in vinegar to wash out the mold, and even afterwards, I didn’t feel comfortable using the bags anymore. The potential for mold on natural textiles can be a barrier, so I decided to try different materials.

Proposed Design

My proposed design concept is a reusable bread shopping bag that shoppers will bring with them when bread shopping. This design would satisfy all of the criteria set earlier.

The bag is made from 2 waterproof fabrics. The opaque material needs to be moisture wicking and breathable so that excess moisture from the bread can leave the bag. However, it is waterproof so no water will enter. The clear material will provide visibility for the bread inside.

Both bag designs offer more affordances than the existing bags in the market. The bread loaf bag has a roll-top closure system that can be used to adjust the size of the bag. If the bread inside is smaller, the shopper can roll down more before closing. The roll-top design also creates a handle. This affords the user to carry in their hand, or it can be worn on the forearm, freeing up the hand. The baguette bag can be carried on one shoulder, or cross-body. The strap can be adjusted to the right tightness.

This design would keep bread fresh longer by keeping moisture and contamination and out, while wicking existing moisture away from the bread. The bag itself will also stay in circulation longer; by reusing the bag, shoppers help keep plastic bags out of landfills. And if they like the bag, they are more likely to continue using it.


Semiotics Case Study: Bread Bags (Part 1 of 2)


For this project, I chose to do my research on bread and baguette packaging. I am passionate about food packaging because I live a zero-waste lifestyle. While I understand that packaging is necessary for the transportation and storage of food, I also believe that their impacts can be minimised through better packaging design. In this section of the project, I will be comparing and analysing two existing bread bag designs. The two designs of the product I want to focus on are: side gusseted bags with window, and clear wicketed bag.

Side Gusseted Bags with Window


The primary function of this packaging is to visually display the contents. These bags are typically used in stores where customers help themselves to the products, such as a convenience store or a grocery store.

The main body of the bag is made with ribbed kraft paper. The window is made with polypropylene (PP), a thermoplastic polymer, and is also known as #5 plastic. These materials are used because they are both approved to be food safe. They are both also recyclable, but they must be separated before recycling. In the Metro Vancouver area, the paper component of the bag can be recycled through the recycling bin the municipals provide for the building. However, the plastic component must be brought to a depot to be recycled.

The triangular gusset at the sides allows for the top of the bag to be bigger than the bottom. The bottom of the bag is flat, which means that the bag cannot stand on its own. In stores, the baguettes are typically displayed in a basket so they stand upright  and the bread loaves are displayed by stacking them in front of each other in a low basket (see photos below).

The bag design uses implicit elements and affordance to communicate its use. There is affordance in the design such that the paper can be printed. Typically, the front side of the paper bag (the side with the plastic window) would have the company logo. The back side would have additional information about the company, and sometimes also instructions on how to recycle the packaging. The opening is also an affordance since it allows one to put in and take out the contents. The lack of handle on this bag design implies that the bag should not be held with the hand, but the arm instead.

This bag design applies a simple metaphor – the plastic section is like a window that allows users to see what is inside. It is aesthetically pleasing due to the combination of materials. The style can be seen as bricolage since it utilises paper (traditional and natural material) and combines it with plastic (modern and synthetic material) almost seamlessly.

The visceral aspect of the design comes from the material of the bag. The kraft paper is typically associated with eco-friendly products due to its natural elements. However, the plastic section can cause confusion to the consumer since plastic products are viewed as polluting and flimsy. The behavioural aspects of the design are not very positive since the bag doesn’t function well. The open top means that the bread can easily fall out if not held upright. It also means that the bread is not protected against contamination. In cases where the bread is longer than the bag, it sticks out the top and is likely that someone else has touched it. The mix of materials used in the bag also makes it more difficult to recycle because it needs to be separated. The reflective elements of the design focuses heavily on our desire to consume products that appear more environmentally friendly. We want products to be packaged and presented nicely, even though the packaging may be ineffective.


Clear Wicketed Bag


Wicketed bags are bags that are stacked and held together on a metal wicket that acts as a dispenser. The primary function of this packaging is to securely enclose the contents for transportation and to protect the contents from moisture and other contamination. In store, they can visually display the contents. These bags are typically used by large baked goods distributors, and the goods are packed inside the bags before they are transported. The bag requires a bread clip or twist tie in order to be secure the contents.

The entire bag is made with 1.25mil clear 100% virgin Low Density Polyethylene (LDPE), a thermoplastic polymer, and is also known as #4 plastic. This material is food safe and recyclable. In the Metro Vancouver area, the bag must be brought to a depot to be recycled. The waterproof aspect of the plastic makes it ideal at keeping out moisture and contamination. The plastic will also preserve the moisture inside the bag and soften the crust of the bread. However, this also causes the bread to grow mold at a faster rate.

The bag design uses affordance to communicate its use. There is affordance in the design such that the plastic can be printed on. These bags have a bottom gusset to provide neat presentation of products, as well as extra space for displaying the brand logo and other information. The large surface area also affords stores to place their own stickers and labels, so the same bag can be ordered in bulk to save on costs, and they would just print new labels each specific product when they are needed. The extra plastic sticking out past the bread clip is often used to hold the bread bag. This can be seen as an affordance in the design, even though the plastic isn’t particularly comfortable to hold. The opening is also an affordance since it affords one to put in and take out the contents.

The visceral aspect of the design comes from the material of the bag. Plastic packaging is seen as a single-use item, so the initial reaction to the product is that it is new and fresh.  The gut instead is to pick the bag that is the newest looking and one that has not been opened.

The behavioural aspects of the design focuses on how the bag makes the shoppers feel. The bags provide a sense of security for both the shoppers and the manufacturers. They can feel at ease that none of the slices of bread will fall out, and that everything inside is not contaminated. With the labelling, shoppers can also easily identify the brand or the type of bread they want to buy. The reflective aspect of the design is how much we value the bag itself. Once the contents are consumed, the packaging is seen as a single-use item to be tossed out.

Analysis Results

Between the two bag designs, the clear wicketed bags manifests their usage and function more clearly. This is because the bag has more useful features overall and is easier to recycle since it only consists of one material. Also, all parties involved (bakeries, stores, and shoppers) get a sense of security with this bag design. They can feel at ease that none of the slices of bread will fall out, and that everything inside is not contaminated. And if there is something wrong with the bread, it is easy to see it though the clear plastic. The only downside to the plastic is that it traps the moisture inside. This leads to the crust of the bread to get soft. It also decreases the bread’s shelf life because mold grows faster from the trapped moisture.

Continue to part 2

Truss Bridge FE Analysis Using SolidWorks

The purpose of this assignment is to use find the maximum force and point(s) of failure of a design.  A 50cm long truss bridge made out of birch popsicle sticks is to be built using Solidworks before building the real thing. A weight will be hung across the 1/3 section of the bridge.

The Bridge Design

Using Solidworks, I designed my bridge with reversed triangles starting at the point at which the force would be applied. This should carry the stress along the top beams and distribute the weight throughout the bridge.


I ran a simulation to find the maximum force that can be applied before failure. I was also able to determine the point of failure in the design. According to Solidworks, bridge will break at the point of stress at 70kg.

Truss Bridge_stress

The building of the real bridge was difficult because many of the popsicle sticks were warped and were not glued on perfectly straight. Theoretically, if the glue does not fail, the bridge should break because the popsicle sticks break



Test Results

The bridge broke exactly where Solidworks predicted. The glue did not fail so both bottom beams broke because the popsicle sticks snapped in half. The actual bridge weight 136g and withstood 46kg, which is almost 340 times it’s own weight!