02 August 2010

Harold McGee and Tony Conigliaro

To many within the audience, Harold’s book ‘On Food and Cooking’ has been a rich document of source material, and the lecture lived up to expectations.

Much of the discussion involved Tony and Harold investigating commonplace food and bar ingredients and their applications. Often these ingredients are over looked, or badly utilised. By understanding the structure of these ingredients, Tony and Harold could show methods of getting the most from these ingredients, and avoiding pitfalls that can accompany many standard techniques.

First up for inquiry was lime juice. Tony explained how the complex aroma of fresh lime was not only one source. To show this, three fragmented lime concentrates were passed around. Individually they smelt characteristically of lime- albeit fractions of- but when combined, they reformed the aroma of true, fresh lime.

Harold explained the oxidation of lime juice occurs very quickly after pressing, and the contrast can easily be seen. The audience smelt and tasted freshly pressed lime against lime juice that had been heated to 90°C then rapidly cooled to illustrate the effects of oxidation. Unfortunately, the conclusion reached was that there were few means of avoiding this, and the solution was to have juice prepared as close to requirement as possible.

In contrast, in the analysis of mint, there were means of better utilising the ingredient. This was achieved first through a better understanding of the plant itself. The mint ‘essence’ lies in small sacks that occur on the underside of the leaf. When damaged, they release the mint oils that are desired (ironically, this is actually a natural repellent and wards off pests, but it is this aspect we desire).

They are also very fragile, so over-handling of the mint, and the misinformed notion of muddling the mint subdues flavour- and in the case of muddling, releases bitter chlorophyll from within the cells. The flavour can easily subside however, and can also take on undesirable notes, so to demonstrate, Tony had prepared two hydrosols- water based essences created using the vacuum still that can preserve the integrity of ingredients in a water based solution. Akin to the lime juice, a bad mint and a good mint hydrosol were passed around. Not only did this demonstrate a means of preserving the mint (if you have a vacuum still!), it also allowed Tony and Harold to discuss the nature of mint as a plant and its correct treatment.

This gave Harold a platform on which he could discuss the development of flavours and compounds and resulted in an analysis of Tony’s Vintage cocktails. Harold explained, using a chromatograph reading illustrating the compounds present within aged and un-aged examples, how ageing created a complex interplay between the compounds- shown with batches of Vintage Manhattans- that leads to not only a mellowing of flavours, but also the creation of new ones. The combination of vermouth, Bourbon and bitters interact over time and create a very different product to that of a fresh mixture.

From this, Harold could develop on to his studies into the effects and behaviour of alcohol molecules, and his findings showed how in high concentrations, it behaves similarly to that of oil when in the presence of water. This was an important revelation, as it seems that alcohol molecules form micelles; whereby the hydrophobic heads of the molecules cluster together to minimise water contact (akin to the indicative droplets of oil in water), the application of this may not be enormous to the average chef or bartender, but an interesting report nonetheless!

A fitting end to the showcase of the Barshow, and an enormous wealth of information passed on by all the guest talkers, with the signed posters being sold for charity quickly snapped up. With new works soon available from a few of our lecturers, this was a perfectly timed conference!

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