How do I get beautiful poached eggs like the ones in my cafe? L. Bowman

There are some household jobs that are best left to experts. Animal surgery, inground pool electrical work and poaching perfect eggs. This is a job for the professionals. There is a chef at Proper and Son at the South Melbourne market who makes amazing tadpole-shaped poached eggs that look a little like the head from Edvard Munch's The Scream. All egg whites, no matter how fresh, have thicker, more viscous parts and thinner, runnier parts. The runnier part of the egg white dissipates quickly in hot water, setting into a white shroud that looks like a pale Harry Potter dementor haunting the yolk. You can strain this away before you poach the egg by cracking the egg into a fine mesh sieve then sliding the yolk and thicker part of the white into swirling, gently simmering salted water. The vortex in the water helps the egg white form a pleasing globe. The idea of acidulating water by adding a dash of vinegar does have some scientific basis – the acid de-natures the protein. But in doing so it tends to overset the egg as it cooks.

Why is a passionfruit called a passionfruit? G. Everard

Back when I was growing up, black moccasins were de rigueur and the mullet was as ubiquitous as the hipster beard is today. I remember a very young single mother-to-be who was intent on calling her child, if it was a girl, Passiona, after the passionfruit-flavoured drink. Centuries before, in South America, Christian missionaries were explaining the crucifixion of Jesus using local flora as a handy pneumonic. One fruit-bearing flower, Passiflora edulis, became known by the locals as La Flora de las cinco lagas or Flower of the Five Wounds. The missionaries used its five stamens to describe the five places Christ was punctured, nails in each foot and hand with a spear thrust into the side. The three stiles represented the three nails and the corona, the crown of thorns. So the saga of Jesus's suffering, also known as "the passion", was bestowed on the flower of the fruit. Today we bestow the pulp of the fruit on sponges and pavlovas. You can strain the pulp and use the aromatic juice to flavour desserts.

What is the jelly at the bottom of preserved limes and lemons? G. Parry

Preserved lemons received as a gift can sit for years in their jar in the fridge in an emotional no man's land. Too precious to throw away, too exotic to use every day, the citrus silently transforms in the jar, the starch in the cell walls – pectose – slowly converting to pectin. Pectin, as you know, sets jelly. Liquid exuding from the fruit settles at the bottom of the jar and the pectin turns it into a jelly. There is a sensational recipe for preserved lemon in Stephanie Alexander's Moroccan-inspired chicken in her Cook's Companion – a delicious dish of chickpeas, pumpkin, chicken, coriander, cumin and preserved lemon.

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