There are two common varieties of pickled ginger in Japan (and a bunch of less common ones). The "gari" is "amazu-shouga" (甘酢生姜 or 甘酢しょうが) it's usually thinly sliced and often, though not always, left uncolored, or just colored enough to leave it slightly pink instead of yellowish-white. Due to generous use of sugar or other sweeteners, it's usually somewhat sweet, and that's right there in the name, which roughly translates as "sweet vinegar ginger". It's generally made with a young ginger that has a pretty thin, moist skin.
Another variety, which typically comes in the shape of thick matchsticks, is a bit saltier and, because of the thickness, a bit firmer. It's called "kizami-shouga" or (きざみ生姜 or きざみしょうが). Kizami refers to the shape, not the flavor. Occasionally this will be labeled "beni-shouga" (紅ショウガ), which means red ginger. I believe that more mature ginger is used for kizami-shouga than is used for amazu-shouga. It's generally used to garnish and season things like yakisoba or okonomiyaki, but is not typically served with most types of sushi. The amazu shouga is more common for most sushi.
So it's possible that you've picked up kizami-shouga instead of amazu-shouga. While there's nothing stopping you from adding sugar or other sweeteners from the brine, that probably won't help that much. If you do have amazu-shouga, it's also possible you've just found one that doesn't taste that good. The quality of packaged Japanese pickles I've found in the US isn't all that great, though I've occasionally found decent umeboshi.
You might try a different brand, or consider pickling your own ginger. The basic process for pickling the ginger is a hybrid between salt pickles and vinegar pickles: You peel and thinly slice the ginger, and rub it with salt, leaving it for at least an hour or overnight to sweat. You'll then add a solution of sugar and rice vinegar, occasionally with a little bit of ume-zu, which is the salty brine extracted from umeboshi-making, or beet juice, if you want to guarantee a pink color.
I have done several sushi dinners at home: a lot of fun and also a giant saving! One thing that you need to consider is the amount of fish, sushi recipes call for small amounts and so, even if you are preparing straight sashimi, I found that as 'little' as two pound of fish will 'force feed' a team of 6-8 hungry adults. Wish sushi grade fish you obviously don't want to do it wrong and get sick, so I suggest you stay away from home sanitized cuts. The problem is not only the extended frozen period, but also the way the fish has been handled from the moment it's caught. After searching and talking to the best restaurants in San Diego, I found that http://www.catalinaop.com is one of the best suppliers available. I was lucky enough to be able to swing by their warehouse and avoid the shipping cost, but they offer next day delivery at a reasonable price. The quality and variety is outstanding and they are specialists that will answer every single question! Make it special! :)
Hope it helps :)
Best Answer
That's not really true in any meaningful way, and has nothing to do with sushi. It sounds like the author was just trying to make it sound scandalous to attract attention.
It's a really, really sensationalized version of something true about at least some species of shrimp. They're essentially all born male, so before they can reproduce, naturally, some of them have to turn into females. The bit about siblings is essentially made up; sure, each shrimp has a lot of offspring, so some probably do randomly reproduce with a "sibling", but it's not like they're seeking it out. The younger part is true in a sense, though, since they turn from male to female but not back, so naturally the males are younger than the females. See for example this page.
I don't think those species are the only ones used in sushi, though, so all in all, the statement is essentially false. Not all shrimp change sex, in the species which do that, not only older ones (which have changed sex) are caught, and not all of them mate with siblings. I'm sure someone has eaten sushi made with a female member of one of those species which did happen to have mated with a sibling, but that's nothing to write a book about.