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food-fraud
food-fraud


Author Comment Last activity Moderation
elaineyuyu "Hi Chris, thank you so much for your answer! It seems we will have to purchase one of those expensive multispectral cameras, since we need to ident..." | Read more » over 4 years ago
cfastie "Spectrometers based on consumer cameras, like the Public Lab spectrometers, can be built so they provide good information about which narrow wavele..." | Read more » over 4 years ago
shanlter "Thanks @Liz, last year, there's a big scandal on gutter oil in Taiwan. https://en.wikipedia.org/wiki/2014_Taiwan_food_scandal " | Read more » almost 7 years ago
liz "Hi @ygzstc, i heard from Li Zhou and He Shan in Guangzhou who asked me to pass along a question about detecting "recycled" food oil, AKA used resta..." | Read more » almost 7 years ago
ygzstc "Himmm...I was aware of straylight's great research note but the linearity you mentioned there is not about webcam but about peak heights vs. concen..." | Read more » almost 8 years ago
warren "Automatic exposure control is not disabled -- but some tests have shown webcams to be pretty linear: http://publiclab.org/notes/straylight/05-13-20..." | Read more » almost 8 years ago
ygzstc "Thanks Chris :) As far as I know, this seems to be the standard way to compare absorbance spectra...But modelling part may vary depending on the t..." | Read more » almost 8 years ago
cfastie "I proclaim this study to be highly replicable, and encourage others to reproduce Yagiz's results. Not that we should have any doubts about Yagiz's ..." | Read more » almost 8 years ago
stoft "Ok, so the plots are absorption; which makes more sense. However, the Y axis is labeled "Intensity". It would be more clear to either plot relative..." | Read more » over 8 years ago
ygzstc "Dave - Thanks a lot for the insights...As you said, when I add oil sample, intensity decreases and since the plots above is the difference between ..." | Read more » over 8 years ago
jeffh "Very nice work. I checked the listing for the lamp, and if you are using the original bulb, it is a "warm white" with color temperature of 2700 deg..." | Read more » over 8 years ago
stoft "Nice experiment. As I recall, white LEDs have a significant 'bump' at about 430nm, a dip at 470nm and a broad peak about 600nm so I assume the 470 ..." | Read more » over 8 years ago
liz "Wow this is fantastic!!! I can't wait to try this method~! " | Read more » over 8 years ago
ygzstc "Jeff, I am sure it can be done. However, coding is not my strong suit :( I may help on theory and algorithm development though... Cfastie, you are..." | Read more » over 8 years ago
cfastie "This is excellent research. Do you think if I bought some "100% extra virgin olive oil" and sent you a sample, you could tell me if it was really 1..." | Read more » over 8 years ago
warren "Wow, this is spectacular -- thanks! I'm wondering if there's a way we could write a macro for Spectral Workbench to do this kind of analysis in rea..." | Read more » over 8 years ago