Question 1

Why do onions and garlic burn so easily?

Accepted Answer

Because both contain a high proportion of **sugars** relative to water, and garlic in particular is small, thin and low in moisture — so it passes from cooked to burnt very quickly.

**The chemistry.** Onions are roughly 5–9% sugar by weight, mostly fructose, glucose and sucrose. Sugars caramelise at relatively modest temperatures, and once caramelisation begins it accelerates. Past a point, the sugars **pyrolyse** into bitter compounds, and that transition is not reversible.

**Why garlic is worse than onion.** Garlic is typically cut far smaller, so it has an enormous surface area relative to volume and very little internal moisture to buffer it. Chopped or crushed garlic in hot oil can go from fragrant to acrid in **under a minute** — and burnt garlic makes an entire dish bitter, in a way that cannot be cooked out or masked.

**Crushing makes it worse still**, since it releases more sugars and more surface area than slicing.

**What to do about it:**

**Add garlic later than onion.** This is the main answer, and the most common recipe error is adding both together. Onions take 8–10 minutes to soften; garlic needs **30 seconds to a minute**. Cook the onion first, then add garlic at the end of that stage.

**Add it to a wetter environment.** Adding garlic after liquid or tomatoes have gone in removes the risk entirely, since the temperature is capped near boiling.

**Lower the heat** when garlic goes in.

**Cut it larger** where a recipe allows — sliced garlic is far more forgiving than minced.

**Watch the colour.** Pale gold is done. Any brown at the edges means stop.

**If it burns, start again.** Bitter compounds do not disappear, and attempting to rescue it wastes the rest of the ingredients.

**Where the same problem appears:** caramelising onions properly takes 30–45 minutes on **low** heat, and recipes claiming ten minutes are describing browning rather than caramelising.

Question 2

Why does my garlic turn blue or green?

Accepted Answer

It is a harmless chemical reaction, not spoilage, and it is more common in pickled garlic and in dishes with acidic ingredients. Garlic contains sulphur compounds and amino acids. When the cloves are

Question 3

Why does a sharp knife matter?

Accepted Answer

Because a sharp knife is safer, faster and produces better food — and the safety point is the one that surprises people, since a blunt knife is the more dangerous tool. Why blunt is dangerous. A

Question 4

Why does cutting food the same size matter?

Accepted Answer

Because cooking is a rate, and pieces of different sizes cook at different rates — so uneven cutting guarantees that something is overdone by the time the largest piece is ready. The physics. Heat

Question 5

Why do recipes say to fry spices before adding liquid?

Accepted Answer

Because the compounds that carry most spice flavour are fat-soluble, and heating spices in fat extracts and disperses them in a way water cannot. The technique is called blooming, and it is the

Question 6

Why do green vegetables go dull when cooked?

Accepted Answer

Because heat and acid destroy chlorophyll, converting the vivid green pigment into a drab olive one — and the change is chemically specific and largely preventable. What happens. Chlorophyll contains

Question 7

What actually happens when sugar caramelises?

Accepted Answer

Sugar melts, then breaks apart and recombines into hundreds of new compounds — which is why caramel tastes nothing like sugar and why the process is irreversible. The stages. Heated sucrose melts

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