Great question! It looks as if the jury is still out on this one. Some people suggest that (after cooking, at least), some vitamins and minerals leach into the water. These folks recommend saving the cooking water and using it in soups as a way to reclaim some of the vitamin content. See: http://www.livestrong.com/article/465595-do-vegetables-lose-nutrients-when-cooked/

Others suggest that, after draining, the mineral density of the food actually increases. http://cooking.stackexchange.com/questions/28663/nutrient-impact-of-squeezing-water-out-of-frozen-chopped-spinach

Unless you are only planning on cooking with and/or baking the zucchini during growing season, you are bound to lose some vitamin content, either because you process your own veggies, typically right after you pick them, or because the stuff you buy in the store will likely have been picked days before and shipped to the store. I always choose my own produce, whenever possible, since I know what I added to the soil or didn’t apply to the plant (pesticides.) 🙂

You can keep it from getting watery by adding salt before you freeze it. Here are a couple of sites I’ve looked at and considered. https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiy4OXMrLbNAhUDOlIKHT2ABJEQFggeMAA&url=http%3A%2F%2Fwww.popsugar.com%2Ffood%2FSalt-Watery-Vegetables-Before-Cooking-11379955&usg=AFQjCNGoQrOFI-CJL7M6amFr9xLYfR2FbQ

http://www.finecooking.com/articles/zucchini-loves-high-heat.aspx

In the end, I decided I didn’t want the extra salt in our diets, so I just double the amount of zucchini that my baking recipe calls for, drain it after it’s thawed, and let it go at that. It has always worked out just fine, and without the extra salt.

Sure! Here’s a link: http://2019.simplelifeandhome.com/2012/07/12/award-winning-zucchini-bread/