Food fight at the ballot box

With a soft thud and a gentle red spray of pip and pulp, the first tomato of the year struck home - squarely between the shoulders of Tony Blair. When we saw it on the news, most of us smiled and went back to our knitting. But I, with my scientist's mind and thirst for analysis, tossed aside my needlepoint. Instead, I grabbed a white coat, a friendly drycleaner, a bag of fruit and a Tony Blair lookalike. Then I rushed to my laboratory to begin tests.

Is the humble tomato really the best foodstuff to toss at a Premier? What about eggs? Flour? Asparagus tips? I was determined to find out.

Any serious scientific analysis of political food-chucking must take into account the major breakthroughs in the field. Nine months ago we learned a lot about bi-textural hurling from an egg-and-flour attack on Liberal Democrat mayoral candidate Susan Kramer; and the chocolate éclair plunged into the face of Agriculture Minister Nick Brown at a conference last February was a masterpiece of short-range shoving. But the Blair tomato attack brought us back to our roots: the single, well-lobbed item.

The rotten tomato is the yardstick by which all polemical, non-lethal projectiles must be judged. So we began our tests accordingly.

Large Tomato: a good-sized, over-ripe beef tomato with some preliminary epidermal splitting provided a first-rate combination of heft, accuracy and impact.

Small Tomato: a smaller, vine-ripened tomato may be suitable for the younger thrower (age 5 - 11) but none of the tomato family matched the sheer volume of seedy pulp provided by the beef variety. However, my dry-cleaning expert, Robert Shooman of Celebrity Cleaners, Brewer Street, rates tomato pulp as "not too difficult" to get out of a suit. As this is a key factor in assessing suitability for political pelting, we moved on.

The Egg: this is another of the greats. Even the Queen - in New Zealand in 1986 - has felt the cool spatter of yolk on her porcelain skin. It also apparently has a very high stain coefficient (something like eight or nine, depending on whether or not it's free-range). Shooman explains: "Egg is very difficult to shift because the protein binds with the fibres of the suit." The egg is one of my personal favourites. It is easy to conceal, feels good in the fist, flies hard and true and explodes pleasantly on impact. There is also a sense in which it is a more serious projectile than the tomato: it hurts more when it hits, and - if left to go off - has a lingering, rancid reek unmatched by other foodstuffs.

Plain flour: following the Kramer initiative, we added flour to the egg debris, a mixture Shooman rates as "one of the most difficult things of all to get out". The difficulty with flour, though, is in the throwing. I found standing on a step-ladder next to my Blair and pouring the bleached grindings over his neck and shoulders worked best. How this technique would fare in practice, I have no idea.

Chocolate éclair: this performed poorly in tests, I am sorry to say. It was difficult to grip, had a low dispersal ratio, and - according to Shooman - is very easy to clean.

Asparagus tips: these were also a disappointment. Although reminiscent of tiny spears and easy to bundle, they tended to diffract wildly in flight and caused little or no staining.