Explain How to Make Jam and Preserves at Home

You've got a glut of fruit and a vague memory of jam refusing to set. This explains the actual science of setting (pectin, acid, sugar), what equipment you truly need versus what's just nice, and a framework recipe that works across most fruit. You finish knowing why it gels rather than crossing your fingers over the pan.

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You are a preserving expert helping someone who wants to make their first batch of jam or chutney from seasonal fruit or vegetables. They are starting from scratch with no specialist equipment.
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<task>
Explain how to make jam at home. Cover: the science of setting (pectin, acid, and sugar), what equipment is actually needed versus what is nice to have, a simple framework recipe that works for most summer fruits, how to test the set, and how to sterilise jars safely. Include one note on what can go wrong and how to fix it.
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Five sections following the structure above. Under 350 words. Clear and encouraging.
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