Hey hope this helps as I found this post on how u can find when u smell without having someone sniff you, in short what she meant was that u should use an air purifier which will detect when you smell worse and when you don't. This will help u see which foods or anything u do that makes u smell and where u smell.
Here is the long post

"i all,I did a quick study from people who suffered from varying sources of Body Odor and have already posted this on their message board.Hopefully, it will also help people with FBO/LG here.Obviously, the best method is to have a few honest, non-relative individuals sniff you but due to embarrassment or the varying nature/frequency of how odor may present itself, it may be difficult to obtain useful answers. Due to the suggestion of a skype member, I have been experimenting with an automatic air purifier to determine if it can give reliable results on location of odor and strength of odor. So far, it has confirmed the Effect on Environment portion for the above chart. Flatus and expirated air are easier to detect and take some time to "purify." I do not have Body Odor issues with sweat so I have not been able to experiment with detection on this basis [purifier does not detect my sweat.] However I have read a review where an individual claims the purifier does alert him to excessive sweaty Body Odor but the person does not claim to have a body odor condition. Another issue is that although air purifiers (presumably) pick up on a number of VOCs, not all VOCs have an odor. For example, if I breathe for at least 10 seconds or count to 20 into the purifier, the purifier will go off reliably each time but my breath has no bad odor. Asking the other member with a similar air purifier to repeat a similar experiment did not result in a response. Conversely, non-VOCs may cause odor and may not be detected by the purifier. Yet, I believe if odor exceeds the norm, it is most likely due to odiferous VOCs or elevated odiferous VOCs. Depending on how long it takes to purify the air after detection and how high the detection is rated (my purifier has two detection ratings - moderate and high - I can only get it to high by spraying perfume or fragrance near it), an air purifier may be useful in determining odor source, triggers for odor, if any, and intensity of odor. Obviously, I have more experiments to perform and do not suggest people spend hundreds of dollars to do the same. I'll report on any progress.Now for LGers specifically, the $64 million question is does it detect LG? For me, yes it does. Despite taking pro-m, pepto/devrom, and probiotics, the air purifier does kick into moderate detection gear every now and then while I am in front of or near the sensor. I can tell you that it goes off when I have absolutely no sensation whatsoever - no wetness, no bubbling, no cramping. Sometimes it happens when I am sitting and working on my computer, when I sit down in my chair, twist to reach for something, or when I get up to get something. Paradoxically, when I do feel bubbling or a slight release of flatus, the purifier does nothing. Also doesn't detect anything if I do smell some normal smelling flatus (and am aware of releasing it). Right now, I think this discrepancy is due to my taking OTC drugs that greatly reduce hydrogen sulfide and other malodorous VOCs/bacteria. [That's right - I do have two types of odor: one is from treated waste/gas and the other probably from not yet treated waste/gas - my theory so far]. To be absolutely certain, I should (and will) probably stop all meds and continue testing to be certain of symptoms and determine any triggers. Another discovery is that it sometimes occurs within 30 minutes of eating (sometimes w/in 10-15 minutes). And it's often [but not always] after I have consumed corn products or wheat/bread products. Sugar has no effect. I have been tested for gluten intolerance/celiac sprue twice and have been found not gluten intolerant. Yet it is possible LG happens so quickly after eating due to high amplitude propagating contractions (HAPC). May also explain why drugs that affect gut motility also help decrease LG in some people (including myself). With IBSers, the contractions may be so strong...
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These contractions only occur 6-8 times per day in healthy people, but they are extremely strong contractions, which begin in the first part of the large intestine and sweep around all the way to the rectum; they stop just above the rectum. These contractions move the contents of the large intestine ahead of them, and they will often trigger a bowel movement, or at least the urge to have a bowel movement. [Or the contraction will cause any pockets of gas within the intestine to emerge as flatulence - my addition]IBS symptoms are believed to be caused partly by abnormal motility. In IBS, the motor function of the intestines overreacts to stimuli like meals or stress. This reaction can cause the intestines to become too active or not active enough.
Obviously if you have an intolerance or are stressed, odorous gas can move through quickly - probably so quickly that odor reducing medicine may not have a chance to work its magic.I have found that complete evacuation has a slight effect on improving/decreasing LG but it does not stop it completely. Using flax seed 3 times a day has "cured" me of IE and small BMs. Despite normal BMs, the air purifier alerts me that I still get LG regardless - just not as much.Lastly, although this is not a shock, gas odor has less odor when it is not sitting in your gut longer than it should. Same theory of keeping regular bowel movements with TMAU applies with LGers too. Odor reducing medication only works so well. Bacteria will still build up in you and make gas or BMs smell stronger than they would.Anyway, I will update on further experiments. Afterwards, I will probably try to get Solesta treatment esp. now that I have more proof it is odor from the rectum and I have an independent means of determining whether the injections are working or not.P.S. Since I can make the purifier detect odorless VOCs from my mouth reliably, I tested a pair of shreddies I have only worn once for two hours to see if they (and by implication any other type of activated carbon charcoal filter underwear) work. They don't. They did block detection but only for a few seconds. It seems when warm moist air is blown into them (I blew into them about 3 times in a 2-3 minute period), it decreases their ability to absorb odors. To be effective, you cannot have gas more than a few times a day (definitely not in succession) and the underwear must stay cool and dry at all times. If LG happens a lot and/or you sweat - even just a little down there, it's just a waste of money. Makes me wonder about the exact conditions used when doctors tested the various flatus filter products.Hope this helps. "

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