blue pin is locular tissue, green pins; pericarp tissue
I know if I like the taste of something but am not so good at discerning individual flavours.
A wine tasting course and I recall swilling some red round a glass.
Getting wet wool ? we were asked. At that moment I was happy to lack the discernment to identify soggy sheep at a sniff.
However growing tomatoes is different. The angst and aspiration of a home grower deserves great flavour.
Given that it’s not going to be lambs in arm bands or burnt toast that lend flavour to tomatoes, today’s Saturday Swot Shop swills around the issue of what does.
What gives tomatoes their flavour ?
- It’s a combination of sugars and acids which determine the balance of sweet, sour and intensity of flavour.
- The most enjoyable tomato will have high sugar and relatively high acids, the least will have both low sugar and acid.
- If you pucker when you eat it’s probably because you’ve hit on a tomato high in acid and low in sugar and if all you think is so so then that’s a tomato high in sugar and low in acid.
Acids and sugars ?
- Citric acid is key. Levels increase as the fruit matures and by the time the fruit is ripe it constitutes over half the tomatoes acidity.
- It takes over from malic acid which is dominant in early growth. Malic acid is used to provide the vinegary frisson in Salt and Vinegar crisps, so for our much loved tomato, this is a good thing!
- Sugars and in tomatoes, the reducing sugars – fructose and glucose, especially fructose are the complementary part of the tomato flavour. They start to build when the tomato reaches maximum growth and the starch stored in the locular tissue starts to break down.
What influences the levels of acid and sugar ?
- Sunshine, Potassium and the physical construct of the locular and pericarp tissue.
The clouds of confusion descended after sunshine …..
- Sunshine is all about light intensity. The more sun a tomato gets when it’s growing the higher its sugar content will be.
- Potassium levels affect citric acid concentration. Too low and the citric acid will be too low.
And the locular and the pericarp ?
- The pericarp is the fleshy part of the tomato. The locular is the pulpy part, in particular the jelly like stuff around the seeds. Tomato varieties vary in how much of the total weight of the tomato either the pericarp or the locular represent.
- Why that matters to the flavour is locular tissue has much higher levels of acid than the pericarp and the pericarp has more glucose than the locular tissue.
So if you have a tomato variety which as a proportion of its weight has more locular tissue than another tomato variety then it will have more acid which means a better overall flavour.
And – too late but I’ve just thought of a new crisp flavour – Lineker’s Vinegar – Green Tomato flavour crisps !
