Richard Cornish

Various heirloom tomato varieties.
Pick of the crop: Heirloom tomatoes come in a range of shapes and colours. Photo: Melanie Faith Dove

Where can I buy heirloom tomatoes besides farmers' markets? R. Rogers

Tomato varieties are a bit like Tinkerbell and Peter Pan. When people stop believing in them they die out. In a capitalist market where supply meets demand, the delightful-tasting but thin-skinned tomatoes our grandparents grew up with simply didn't fit the tenuous supply chain from grower to supermarket and the demands of lengthy shelf life. They almost became as extinct as the thylacine. Tomatoes back then had names that hinted at their use and provenance. Mayan Indian, Siberian, Campbell 33, Burnley Gem and Mr Stripey sound more like the starting gate at the Dapto dogs than some of the tomato varieties that have thankfully been saved. Wanting broad distribution and easy access to heirloom tomatoes is asking for trouble - supermarkets are already offering greenish-red-looking tomatoes that look the part and are sweet but don't have the same depth of flavour as heirlooms. Try organic and good greengrocers and, if they don't have them, ask for them. Try farmers' markets and produce markets, if you have any nearby. If you have a little space in the backyard, prepare it now for a spring planting and buy some seeds from edenseeds.com.au or diggers.com.au

How can I cook Australian bacon crisp? I am used to the bacon in the US. M. Wishart

It's funny when you write ''Australian bacon'' as most of our bacon now comes from pork grown overseas. Next time you go to the supermarket, try to find bacon that is labelled ''Product of Australia''. I found one in a supermarket the other day - house brand. It was about 20 per cent more expensive than a similar cut made from imported pork. Australian bacon producers are not really into making bacon that crisps. They are more into making heavier bacon, as it is sold by weight, by forcing more water into it. When you fry such bacon, the water, filled with proteins and other compounds from inside the meat, exudes out and stews the bacon before it starts frying. I find the secret to getting local bacon to crisp is to cook it slowly on a tray in the oven. If you're really into crisp bacon, try buying artisan bacon or pancetta. Both are much drier and crisp beautifully.

We have been given some dill seeds. What can we do with them? R. Dodson

Assuming the seeds are from someone's garden and have not been treated with pesticide, you could use them to make dill pickles. This involves placing sliced cucumbers in sterilised jars with brine (salted water boiled at a ratio of 50 grams of salt for each litre of water ) peppercorns and dill seeds, and covering the tops with cheesecloth. After a week or so, spontaneous fermentation takes place, turning naturally occurring sugars in the cucumbers into lactic acid. After this the lids are screwed on. This fermentation, plus the brine and to a lesser extent compounds in the herbs, helps keep the cucumbers over winter. Alternatively, sow the seeds in spring and grow your own dill.

Can I substitute ground almonds for almond meal? A. Wheatley

All nuts are full of oil. When oil is exposed to air, it oxidises. Oxidised oil can taste rancid. Almond meal, such as the type you buy in a packet in a supermarket, will invariably be oxidised to some extent but will do the job. Almonds ground fresh at home will taste fresher and give you a better end product. Make ground almonds by taking blanched almonds and placing them in the food processor and pulse process until the consistency of breadcrumbs. Do not over-process or you will end up with almond butter.

Agar agar

A few weeks back we discussed using seaweed-based agar agar as a gelling agent instead of gelatin. This brought back memories for reader K. Johnson, who used carrageen (Irish moss), another type of seaweed, to make a jelly-like lemon drink for her child to soothe an asthmatic cough. She wrote: ''I can remember my mother using isinglass instead of gelatin.'' This is a protein from the swim bladder (the internal buoyancy device) of certain fish and is still used in the brewing and wine industries to settle cloudy beer and wine. She added: ''That was over 60 years ago. Historically, [isinglass] was the setting agent for most of the traditional English jellies and creams in the 17th and 18th centuries, before commercial gelatin became available.''

Send questions to: brainfood@richardcornish.com.au