Question 1

What is the difference between jam, jelly and marmalade?

Accepted Answer

All three are fruit preserved with sugar. The difference is which part of the fruit ends up in the jar.

**Jam** is made from crushed or chopped whole fruit cooked with sugar. It contains pulp and often seeds, and sets to a soft, spreadable mass rather than a firm one.

**Jelly** is made from fruit **juice** only. The fruit is cooked and the liquid strained — traditionally through a jelly bag, without squeezing, which would cloud it. The result is clear, firm and holds its shape when turned out. Redcurrant and crab apple jelly are typical.

**Marmalade** is made from citrus, and characteristically includes the **peel** suspended in a clear set jelly. Seville oranges are the traditional choice because they are high in both pectin and acid, and too bitter to eat raw. The bitterness that makes them useless as fruit is exactly what makes the preserve work.

Two related terms: **conserve** usually means a jam with whole or large pieces of fruit, sometimes with nuts. **Fruit curd** — lemon curd being the common one — is a different thing entirely, thickened with egg and butter rather than set with pectin, and it does not keep like a preserve.

What makes any of them set is **pectin**, a carbohydrate in fruit cell walls, which forms a gel in the presence of sugar and acid. The three have to be in balance: too little pectin or acid and it stays syrupy.

That is why recipes add lemon juice, and why high-pectin fruits like citrus, apples and currants set easily while strawberries and cherries need help.

Underripe fruit contains more pectin than ripe.

Question 2

Why does fresh pineapple stop jelly from setting?

Accepted Answer

Because pineapple contains bromelain, a group of enzymes that break down protein — and gelatine is a protein. The enzyme digests the very molecules that would otherwise form the gel network, so the

Question 3

What is the difference between gelatine, pectin and agar?

Accepted Answer

Three setting agents from completely different sources, setting at different temperatures, with different textures — and they are not interchangeable in a recipe. Gelatine. A protein derived from

Question 4

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

Question 5

Why do bananas make other fruit ripen faster?

Accepted Answer

Because they release ethylene, a gaseous plant hormone that triggers ripening — and they release a lot of it. Ethylene signals fruit to convert starches to sugars, soften cell walls, change colour

Question 6

What is a roux, and why do sauces split?

Accepted Answer

A roux is flour cooked in fat, used to thicken sauces. Understanding how it works explains most sauce failures. How it thickens. Flour contains starch granules. Heated in liquid, they absorb water

Question 7

Why do recipes say to salt aubergine or cucumber before cooking?

Accepted Answer

To draw out water by osmosis — and for aubergine, the traditional reason given is now largely obsolete, while the real benefits are different from the ones usually stated. The mechanism. Salt on the

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