From my experience and understanding it does not make a difference. But people have there reasons such as the one you suggested, protecting them from "the pests". Lately I've been picking mine early.

...make a difference in flavor?

Not so you'd notice. ;)

Dave

I have been picking cherry toms by the handfuls every day and I usually pick them bright orange and leave them on the counter for a day or two. They taste basically the same as the few I've "missed" that fully ripened on the vine. I am also afraid of critters ruining them before I get them.

I have been very happy with my cherry tomato plants - they have been easy to grow and extremely prolific. Basically they were just "plant and pick".

I think it depends a little on the tomato. Usually, I see a little bit of color (especially early in the season) and pick it, then notice it's not fully ripe so have to let it sit for a day or two. Or, as I did today, ate a small tomato in the garden and then felt a little nauseated because it was not fully ripe. Most big tomatoes do fully ripen off the vine.

But I've noticed that Sungolds never develop the rich orange color or the full fruitiness off the vine -- they need sun to develop their flavor.

While I'm picking I pick. Better a day early than a day late. I can't tell a difference in taste at all.

I never notice a difference. And if you have varieties like Sweet 100 that are susceptible to cracking, then DO pick them right before a rain, especially if the plants were a little dry during the development of those fruits.
Bob B.

The consumer is always right and my customers tell me over and over again that they CAN tell the difference. I grant that you will have a firmer, less blemished and more uniformly colored tomato if you pick it at the breaker stage and allow the color to develop off the vine. Keep in mind that this is the practice that is typically followed for your store bought tomatoes. They might also gas flush them too but the gas isn't the villian, it's the early picking.

Therefore, for all of you that complain about the flavor of store bought tomatoes, what are you objecting to? Likely it's the same practice that you are condoning in your own gardens.

gas flush,CO2 is precisely the problem. It turns the fruit red but does not allow the sugars to develop. The fruits are generally picked before they start to turn. So what you are getting is an immature tomato with a premature red color. However, many stores are now seeing a market for a higher end tomato product and you will find tastier tomatoes and "heirlooms" almost everywhere nowadays. The still don't compare to homegrown but that is another discussion...
Environmental conditions determine the flavor in vine riped your tomatoes vs tomatoes ripened on the counter. An airconditioned house vs the hot outdoors. Rain vs dry indoors. Sun vs no light. All factors being equal, I think the difference negligable as long as the tomato was allowed to mature and was beginning to turn color. Also watch out for tomatoes that begin to turn unnaturally because of BER, insect damage, bent ot damaged vine, diseased plant, sun scald, ect. These tomatoes invariably taste bad.

Sillyrib, Carbon dioxide (CO2) is used in "Modified atmosphere" packaging of many meat and produce comodities but it's ethylene gas or a chemical derivative that produces the tomato ripening effect. Putting a tomato in a paper bag with an apple or banana will produce similar results since those fruits emit larger amounts of that gas than the tomato normally does. But the point is WHY?

In recent years USDA has allowed Carbon Monoxide (CO) to be used for red meats in packaging to maintain the bright red color (Bloom) of the meat. The result is that consumers are tricked into thinking that the meat is fresh even past the expiration date of the meat. Chalk up another one for technology.

We can't control the industry practices used to deceive us but as home gardeners we can certainly control the way that we harvest and handle our own produce.