What is the Cube Rule and How Does it Classify Food?
The 'starch theory of food' is an observational, non-scientific system designed for fun, not for nutritional guidance. It is more commonly referred to as the Cube Rule, and its central premise is that foods can be classified into specific categories purely by considering the location of their "structural starch". The theory uses a conceptual six-sided cube as its framework. By determining which sides of the cube have the structural starch, a dish can be assigned to one of six categories, ranging from a simple 'Toast' to a fully enclosed 'Calzone'. This whimsical approach delights foodies and challenges common perceptions of how we define different dishes.
The Six Primary Categories of the Cube Rule
The Cube Rule assigns a food to one of six main classifications based on where the structural starch (bread, crust, tortilla, etc.) is located relative to the rest of the food. Here are the definitions and examples for each category:
- Toast (Starch on One Side): The simplest form, where the starch is present on only one side. This can be the bottom, top, or any single surface.
- Examples: A slice of pizza, nigiri sushi, or a slice of pumpkin pie.
- Sandwich (Starch on Two Sides): A food where the starch is on two opposing sides, typically the top and bottom, with the filling in between.
- Examples: A classic grilled cheese sandwich, a quesadilla, or a Victoria sponge cake.
- Taco (Starch on Three Sides): The starch forms a 'U' shape, surrounding the contents on three sides.
- Examples: A hot dog, a sub sandwich where the bread isn't completely sliced through, or a folded slice of pie.
- Sushi (Starch on Four Sides): Here, the starch surrounds the filling on four sides, forming an open-ended tube.
- Examples: A falafel wrap or enchilada, where the ends are typically open.
- Quiche (Starch on Five Sides): The food is enclosed by structural starch on five of its six sides. The open side is usually the top.
- Examples: A bread bowl filled with soup, deep-dish pizza, or a cheesecake.
- Calzone (Starch on Six Sides): This is the most complex category, where the filling is completely enclosed within the structural starch on all sides.
- Examples: A burrito, a corn dog, a dumpling, or a pop-tart.
How to Apply the Cube Rule and Its Anomalies
Applying the Cube Rule requires observation and can lead to some amusing conclusions. The classification can be mutable, changing based on the food's state. For instance, a whole pumpkin pie is a 'quiche,' but a sliced piece becomes a 'toast' because the crust only holds the bottom. This mutability is a feature, not a bug, of the theory.
For more complex or layered foods, the Outermost Cube Theory provides a resolution. This extension suggests that if a food contains multiple layers of structural starch, the classification is determined by the outermost starch cube. For example, a breaded chicken breast is initially a 'calzone,' but when placed in a bun, it becomes a 'sandwich'. This meta-rule adds another layer of complexity and humor to the system.
Criticisms and Limitations of the Theory
As a non-scientific system, the Cube Rule has its limitations, primarily highlighted by its humorous nature. The rules can sometimes be inconsistently applied or lead to counter-intuitive results, as demonstrated by the debate over how to classify dishes like nachos or poutine. The classification depends heavily on the interpretation of “structural starch” and the perceived state of the food. Some items, like salads with croutons, present a challenge to the system's logic, suggesting that starch location isn't the only factor determining a food's identity. However, these quirks are all part of the fun.
Cube Rule vs. Scientific Starch Classification
To understand the playful nature of the Cube Rule, it is useful to contrast it with how food science actually classifies starch based on its nutritional and chemical properties. This is where the real-world application of starch theory lies. The table below compares the two contrasting methods of classification.
| Feature | Humorous Cube Rule (The Starch Theory) | Scientific Starch Classification |
|---|---|---|
| Primary Goal | Classify food based on the location of its structural starch for amusement. | Categorize starch based on its digestibility and chemical structure for nutritional science. |
| Basis for Categories | Position of starch relative to a conceptual six-sided cube. | Digestion rate and molecular structure of starch (amylose, amylopectin). |
| Key Categories | Toast, Sandwich, Taco, Sushi, Quiche, Calzone. | Rapidly Digestible Starch (RDS), Slowly Digestible Starch (SDS), Resistant Starch (RS). |
| Health Implications | None; the system has no basis in nutrition. | Significant; digestion rate affects blood sugar, satiety, and gut health. |
| Mutability | A food's classification can change depending on its form (e.g., sliced vs. whole pie). | Starch properties can be altered by processing and cooling (e.g., retrograded starch). |
| Examples | A corn dog is a Calzone. | A cooked and cooled potato contains resistant starch. |
Conclusion
The 'starch theory of food,' or Cube Rule, is a creative and entertaining way to think about the composition of our meals, even though it bears no relation to scientific nutritional theories. It is a prime example of internet culture creating a viral conversation starter out of a simple observation. While real food science focuses on the chemical structure and health impacts of starches, the Cube Rule reminds us that food is also about structure, form, and having a little fun. Next time you grab a snack, you might just find yourself thinking about which side the structural starch is on. For more amusing culinary theories, see the Chris Friedman's blog on the Cube Rule.
A Deeper Look into Starch in Food Science
From a scientific perspective, starch is a complex carbohydrate found in plants, consisting of linked glucose units. Its structure, primarily composed of amylose and amylopectin, determines its digestibility and functional properties. Amylose is a linear chain, while amylopectin is branched. The ratio and structure of these components influence how quickly the body breaks down starch into glucose for energy. This is fundamentally different from the Cube Rule's structural classification.
Types of Digestible Starch
- Rapidly Digestible Starch (RDS): Found in foods like cooked potatoes and white bread, this starch is quickly converted to glucose in the body.
- Slowly Digestible Starch (SDS): With a more complex structure, SDS is broken down slowly, providing a steady release of energy. It is found in whole grains.
- Resistant Starch (RS): This type of starch resists digestion in the small intestine and ferments in the large intestine, acting like dietary fiber. It can be found in raw potatoes, unripe bananas, and cooked and cooled starches.
The study of starch in food science is crucial for understanding nutrition, energy metabolism, and disease prevention, in stark contrast to the lighthearted musings of the Cube Rule.
