The paper I referred to was of course a wine paper, but it had some interesting information that was relevent to storing EVOO in bottles.

But as you asked… The purpose of the paper was to show that in some cases, the amount of browning of a white wine in a bottle of wine could be measured without opening it. Something pretty useful for QC. That abstract statement you referred to was stating that bottles of some colours like antique green absorb quite a bit at the wavelength (420nm) that are known to be good indicators of browning in white wines. Therefore for these coloured bottles it was not possible to reliably measure the amount of browning of the wine contained within them – well not using the traditional wavelength of 420nm.

Incidently 420nm is in the visible range of light so it isn’t that energetic as far as starting off rancidity reactions.

The last statement you refer to says… well if the glass interferes with our readings at 420nm we need to find another wavelength that could be an indicator of browning. What they found that the actual browning of the wine (as measured in a clear glass cuvette), correlated well with the 540 reading when in antique green. So by switching the measurement to 520 when measuring through antique green bottles did a good job of predicting white wine browning.

Lastly, you have to be in the trade to know exactly what the different colours are, but I’m sure any bottle rep would be happy to help if you were in the market for some – but just for now its that greeney turquoisey colour you often see used in expensive heavy wine bottles, and flint glass=clear glass.

RG

Great entry, as ever. I take it that you mean Skouroumounis et al, 2003? Do I correctly read the graph, and the abstract’s statement that “A420 of white wine in bottles of Antique Green or Amber glass could not be measured directly due to a strong absorbance of that wavelength by the glass” to indicate that these colors are nearly impervious to the critical range of UV? If so, shouldn’t these colors be the industry gold standard (lousy pun) — and how does a producer or a consumer know what “Antique Green” is?) Finally, what is the significance of the statement that “a strong correlation was established between measurement of A420 (cuvette) and A540 for white wine in Antique Green bottles and between A420 (cuvette) and either A540 or A600 for white wine in Amber bottles”?

Hm. Perhaps I should be asking the authors … Tell me to PO if appropriate . Thanks again!