The

Summer Food

And Traditional Cooking Rules Of Indian Grandmothers Backed By Science

Cooking Summer Food Only in the Morning

In most traditional Indian households, especially across the plains of North India, Bengal, Rajasthan, and the Deccan, the bulk of cooking was done in the early hours, starting as early as 6 am and ending by 9 am. This might seem purely because the kitchen was cooler during summers, in these hours, so it made sense to start cooking early; although that is partially true, there is some microbiology here too.

Microorganisms can multiply very quickly if food is stored at room temperature, and they thrive at certain temperatures. In peak summer, temperatures in many Indian cities routinely exceed 40°C, which is the ‘danger zone’ for bacterial growth. Cooked food should not be left at room temperature for more than 2 hours. Cooking food in the early morning means it is consumed at its freshest, at the coolest part of the day.

There is ample research to substantiate the fact that countries with hotter climates use spices more frequently than countries with cooler climates. In hot countries, nearly every meat-based recipe calls for at least one spice; the same chemical compounds that protect the spiciest spice plants from their natural enemies are at work today, inhibiting food-spoilage microorganisms. Something mastered by grandmothers.

Using Muslin Cloth

If not muslin cloth, a porous cotton cloth used to strain is a common picture in many homes, sticking to traditional cooking. This also extended to paneer and curd making, where it was used to separate the milk solids from the whey (for paneer and butter). If you move south, this practice is still common in states like Karnataka, which make thatte idlis. This was not about sentiment; it helps in using something biodegradable, good for the environment and also reduces food waste. 

Besides that, the fabric is a loosely woven, breathable fabric that blocks dust, flies, and airborne particles from settling on food without trapping heat the way a lid does, and also protects food from disease-spreading insects like flies. The fabric's breathability also means that steam from recently cooked food can escape, reducing condensation inside the vessel that could otherwise accelerate bacterial growth. 

The Science Behind Curd Rice

Across South India in particular, no summer lunch is complete without a portion of curd rice, for lunch which makes for a filling, refreshing and nourishing meal. Curd rice is simply cooked rice mixed with curd, tempered with mustard seeds, curry leaves, and sometimes tiny pieces of ginger, which are known to aid digestion, something that tends to be sluggish during summer. This simple rice dish is comfort food and medicine in one.

Curd rice was traditionally consumed on a daily basis during summers to prevent sunstroke and beat the summer heat, something which still holds today. Yoghurt is pushed to the spotlight now more than ever as gut health and protein have become more than buzzwords, with research mentioning their benefits. Curd rice brings down the body temperature, and the probiotics in it support gut health, which is under particular stress in summer, when digestion slows, and dehydration is common.

The Clay Pot (Matka) was a Natural Refrigerator

Before refrigerators were mainstream, a life without which is hard to think of today, there was the matka or an earthen clay pot, something Indian grandmothers used to keep things cool, especially water. Earthen pots are used not only for setting homemade curd but also for storing water, cooking rice, and preparing summer delicacies like fermented kanji. 

Clay pot coolers can reduce stored water temperatures by 5-15°C, though it depends on the climate, clay properties, design, size and volume. The science behind this is actually quite simple – the porous walls of an unglazed clay pot allow water to seep through at a microscopic level and evaporate at the surface. Evaporation is an endothermic process, meaning it absorbs heat from the surrounding water, cooling what remains inside. 

Clay is a poor conductor of heat, which is exactly what makes it so effective at maintaining cool temperatures. The thick, earthy walls of the mud pot act as a thermal insulator, slowing down the heat transfer from the environment to the water. Beyond cooling, the matka, made with clay, releases minerals like calcium, magnesium, and potassium into the water, making it alkaline, something touted to help with heartburn.

The Tradition of Light and Seasonal Cooking in Summer

Indian grandmothers, when it came to traditional cooking during summer, shifted to lighter summer foods like curd rice, chaas, thin dals, and vegetable-based dishes, which were light and made with less oil and spices, because heavy eating in extreme heat caused an overworked body focused on cooling to feel physically uncomfortable. So, heavy, slow-cooked dishes like sarson ka saag, paya, and haleem disappear. In comes kanji, thandai, aam panna, sattu sharbat, koozh, solkadhi, and rice-based meals with minimal oil and more curd.

Modern research now supports this unexplained logic. Scientific studies show that hot weather suppresses appetite because digestion itself generates body heat, known as the thermic effect of food, making lighter meals easier to tolerate during high temperatures. Research also links heat stress and dehydration with lower food intake and digestive discomfort. This is why seasonal Indian summer cooking naturally prioritises hydration, softer textures, and simpler meals.

Why These Rules are Worth Reviving

There is a tendency to dismiss grandmother's kitchen rules as old-fashioned caution or as superstition. But each of the practices outlined above was built on observation across generations, and each has now found a counterpart in food microbiology, Ayurveda research, or materials science. As India's summer temperatures rise year on year, the logic of these practices becomes more relevant, not less.