No one prevents you from having a hot broth in the summer, but you’re unlikely to do so. Nor do you usually order a cold gazpacho in winter, nor do you drink melted ice cream. Beyond the suffocating feeling that the idea of having a soup in the middle of a heat wave gives us, or the disappointment of seeing your scoop of ice cream turn to liquid, experts in organoleptic nuances and pleasure at the table point to an invisible condiment: temperature as a key factor for palate satisfaction.
“Not only does it modify aroma, flavor or texture, it also changes our expectations, memories and even the emotions we associate with each dish. That’s why a hot salmorejo or a cold consommé can be disconcerting, even though from a nutritional point of view they are perfectly valid,” comments Anto Martínez Llorente, dietitian-nutritionist.
What’s Behind Temperature?
Raise the thermometer and we forget about soups, stews, hot legumes and pots in general. At our table we only get cold salads and creams, sandwiches of roasted meat at room temperature and refreshing drinks, even cold coffee and milk for breakfast.
“There is no nutritional reason why a salmorejo should be eaten cold or a consommé only hot. However, our perception of the food changes with temperature. In the case of salmorejo, cold enhances its refreshing character and maintains that creamy texture. If we heat it, the sensory balance of the dish changes and it stops conveying the sensation we expect“, sustains.
With consommé the opposite occurs. Heat favors the release of aromatic compounds from the broth, intensifying its smell and making them more easily perceived. When served cold, as the nutritionist asserts, “those aromas reach the sense of smell with less intensity and the result tends to seem less appetizing.”
The New Cuisine Alters the Temperature of the Dish
Alberto Bastard, resident chef at the Cala San Miguel hotel, Ibiza Resort, gives us his culinary take, scientifically speaking. “In gastronomy almost anything goes, but I personally wouldn’t heat a salmorejo: I would lose all the essence and freshness that characterizes this dish. But a well-prepared consommé can surprise served cold,” he notes.
In his view, “cooking evolves when we dare to change habits without losing respect for the product and the technique”.
Emotions on a Plate
For his part, David Berniger, psychologist-nutritionist and creator of the Ankshu Method, a system of guided fasting, detox and metabolic change, believes that “the temperature of foods is not a minor detail. We do not eat nutrients alone: we also eat temperature, texture, memory, season of the year and emotion”.
We could drink a hot salmorejo and a cold broth, but the experience would change. A hot salmorejo would still have tomato, olive oil, garlic and bread, but it would stop speaking the same sensory language. The salmorejo belongs to the summer universe: freshness, acidity, hydration, lightness. If we heat it, garlic might feel more invasive, the tomato changes its aromatic profile and the texture can become heavier. The food may be the same, but the brain does not interpret it the same way. Temperature changes the message”, he notes.
The Menu Also Has Seasons
We live in a world where we almost no longer differentiate the seasons of the year due to the constant use of exaggerated climate control. And because at the supermarket we can find the same foods almost all year round. So, why not have broth when we’re at 20 ºC thanks to air conditioning? “It seems that we choose foods based on the ambient temperature, but reality is more complex,” says Berniger.
Actually, with food we behave like with fashion. Even if a day turns very hot in March, we won’t wear sandals because it seems odd. Nor will we pull out a turtleneck sweater in September even if the mercury drops. Our brain combines information from the environment, hydration status, memory and culinary culture. We know it’s summer, there are more hours of light, we change our routine and for years we have learned that in this season fruits rich in water, gazpachos and salads predominate.
All of this creates a very powerful expectation about what one ‘feels like’ eating —explains the nutritionist—. Even if we are in a perfectly climate-controlled house, “we continue associating broth with winter and gazpacho with summer because the subjective perception of heat greatly influences food choice.”
David Berniger agrees and adds: “We eat according to bodily memory and the emotional desire of the moment. In July, our brain is in ‘summer mode’. Light clothing, vacations, the beach, rest, being outdoors. In that context, the body usually asks for freshness, hydration and lightness. A hot broth is associated with winter, with getting sick, with grandma, with the sofa and rain. That’s why in summer we keep it away, even though objectively we’re not warm inside the house.”
It Also Depends on the Country
The Cala San Miguel chef offers his view from a cultural perspective. “I grew up in the Caribbean, where it’s hot practically all year round. Yet broths are part of daily nourishment, regardless of temperature”.
There they are understood as a nutritious, comforting and flavorful dish, not as a recipe exclusive to cold days. “It’s not a question of climate, but of customs. Gastronomy is full of habits we take for granted… until you meet other cultures and discover that there are also other ways to enjoy the same recipe,” he adds.
What Does a Hot Dish Smell Like?
Different emotional and sensory mechanisms lead us to salivate at the thought of a hot broth and disgust us if served cold. “On one hand, part of the flavor depends on smell. Heat causes more aromatic compounds to be released and reach our nose during chewing or swallowing, and we perceive the food as more intense.
Temperature also activates specific sensory receptors in the mouth, belonging to the trigeminal system, which participates in sensations such as heat, coolness or spiciness.
But perhaps the most interesting factor is emotional. Just by smelling a steaming broth or thinking about it, saliva production increases. Those associations generate an anticipatory response. When the outcome is not as expected, it breaks our expectations and that incongruity reduces the pleasure we feel. Many times we do not reject a food because of its taste, but because it does not match what our brain expected to find. “Heat intensifies the perception of the food, softens textures and prepares the digestive system. That’s why a hot broth can make us salivate even before trying it. The aroma rises, envelops, anticipates care and activates desire”.
The Nutrients Don’t Budge
From a sensory point of view, the same food can seem completely different depending on the temperature at which it is served. It changes the texture, density, the intensity of the aromas, the perception of sweetness, bitterness, spiciness, and acidity. But from the nutritional value perspective, the differences are smaller.
“If we heat or cool a prepared food, its content of proteins, fats, carbohydrates, fiber or minerals hardly changes. Some heat-sensitive vitamins may be affected,” assures the nutritionist.
Heating a Fermented Drink? Better Not
Although in some areas beer is drunk at room temperature and wine is enjoyed warm. But if what we want is to benefit from microorganisms, bacteria and yeasts in trendy beverages like kombucha, there is no point savoring it as a hot tea because “heating to high temperatures will reduce or eliminate much of those yeasts, bacteria and antioxidants“, concludes Anto.
Certain organic acids and part of the polyphenols will remain, but their sensory profile will change notably: “The perception of acidity will increase, aromas will be altered and it will no longer be a ‘living drink'”.
