Jim Lahey, Elasticity and Bread: Science and Cooking Public Lecture Series 2015 | Summary and Q&A

TL;DR

Elasticity is a key factor in determining the mouthfeel and texture of foods, and it can be described and measured through concepts like squishiness and springiness.

Transcript

PIA SORENSEN: The scientific theme of this week is elasticity. And the reason we talk about elasticity in this class is that it is-- so if you want to be scientific about this, it is kind of one of the closest ways you can get to describing things like mouth feel and texture of foods. So if you think about what makes a good food be the way it is, y... Read More

Key Insights

• 😋 Elasticity is an essential concept for describing and understanding the mouthfeel and texture of food.
• 😋 It can be measured by observing how food responds to applied weights.
• 👨 Elasticity can be affected by factors like molecular structures, fat content, and protein quality.

Questions & Answers

Q: How does elasticity relate to the mouthfeel and texture of food?

Elasticity is one of the closest ways to describe mouthfeel and texture in scientific terms. It can provide insights into the squishiness, springiness, and overall texture of various foods.

Q: What are some examples of how elasticity is observed in foods?

Elasticity can be observed in foods like steak, tofu, and jello. For steak, its texture changes from soft and squishy to firm as it is cooked. In tofu, elasticity can be measured by applying weights to observe how much it squishes.

Q: How is elasticity measured in food?

Elasticity can be measured by applying weights to food and observing its response. For example, in tofu, weights are placed on it to determine how much it squishes, and in steak, weights are used to measure changes in height.

Q: What factors affect the elasticity of food?

The elasticity of food can be influenced by various factors like the molecular structure of gluten in baking, the presence of fats and oils, the percentage of fat in meat, and the quality of protein in wheat used for baking.

Summary

In this video, Pia Sorensen discusses the scientific concept of elasticity and its connection to the mouth feel and texture of food. She explains how elasticity can be used to describe the texture of solid foods like steak and tofu. Sorensen also mentions the role of fat and other factors that affect the squishiness of meat. Jim Lahey, a bakery owner, joins the conversation and discusses the process of making dough and its elasticity.

Questions & Answers

Q: What is the scientific theme discussed in the video?

The scientific theme discussed in the video is elasticity and its connection to the mouth feel and texture of foods.

Q: How is elasticity used to describe the texture of solid foods like steak and tofu?

Elasticity is used to describe the texture of solid foods like steak and tofu by measuring how much squishing occurs when pressure is applied to the food. The more a food resists squishing and maintains its shape, the higher its elasticity.

Q: Can elasticity also be used to describe the texture of liquid foods?

While elasticity is more commonly used to describe the texture of solid foods, it can also be used for liquid foods that have a certain level of thickness or viscosity. In liquid foods, viscosity is often a more important property to consider.

Q: How does the elasticity of steak change when it is cooked?

The elasticity of steak changes as it is cooked. Raw steak has a low elastic modulus, meaning it is squishy. However, as it is cooked, the steak becomes firmer and less squishy due to changes in its molecular structure.

Q: How can the concept of elasticity be applied to the molecular structure of gluten?

In the case of gluten, the strands of glutenin and gliadin proteins bind together to form long networks. When pressure is applied to gluten, these networks exhibit elasticity, similar to what happens with steak or tofu.

Q: What are some factors that can affect the squishiness of meat?

Several factors can affect the squishiness of meat, including the percentage of fat in the meat, the density of the fat compared to the density of muscle, and other factors such as the composition of the meat itself.

Q: Why does mouth feel matter in relation to food texture?

Mouth feel matters because it is connected to the concept of sensual pleasure. A food that feels good to eat is more likely to be enjoyable and make people want to eat more. This is why food with a high sugar content is often eaten in larger quantities.

Q: How does the process of making dough demonstrate elasticity?

The process of making dough involves manipulating the gluten proteins to align and form a cohesive structure. By kneading the dough, the proteins become more aligned, causing the dough to exhibit elasticity.

Q: Are there different methods for making dough that can affect its elasticity?

There are different methods for making dough that can affect its elasticity. The video demonstrates one method called the no-knead method, which involves less physical manipulation of the dough. Other methods, such as using a stand mixer, can produce similar results with less effort.

Q: What are some potential drawbacks of the method demonstrated in the video for making dough?

The method demonstrated in the video for making dough can be messy and time-consuming. It requires more physical effort compared to other methods, such as using a stand mixer. Additionally, handling wet dough can be challenging and may result in splattering.

Takeaways

Understanding elasticity is key to describing the mouth feel and texture of food, particularly solid foods like steak and tofu. The molecular structure of gluten and other proteins plays a crucial role in determining a food's elasticity. Different factors, such as the percentage of fat in meat, can affect the squishiness of meat. Mouth feel matters because it influences the pleasure we experience when eating food. There are various methods for making dough, each with its own pros and cons, but understanding the concepts of elasticity can help in achieving the desired texture.

Summary & Key Takeaways

• Elasticity is an important scientific concept in food texture and mouthfeel, especially in solid foods like steak and tofu.

• It can be measured by applying weights to the food and observing how it squishes or changes in height.

• Elasticity is influenced by factors like the molecular structure of gluten and the quality of wheat used in baking.