On my 4th wine ferment. First one-blackberry- fermented fine and I fixed the odd smell and taste with copper pennies in the bottle for about an hour or so and it's like magic- a very tasty blackberry wine appeared. Second strawberry must did not ferment- I got frozen berries from store brand X. Third one, strawberry, is great- I got the frozen berries from store brand Y. Fourth strawberry batch also did not ferment- got the frozen beries from again store brand X. I'm thinking that one store brand X gets berries that've been sprayed or gassed and that does not allow yeast to take hold, while store brand Y has untreated berries. Both packages have only strawberries listed as ingredients. I've tested my yeast and slowley added must a little at a time and at a point the fermentation stopped in the starter glass. I added it anyway to the must and watched as nothing happened after 10 hrs. Is this a thing that some frozen fruit is gasses or sprayed and it isn't listed and could it affect fermentation? I controlled for variables of temperature and additives. The unfermented must had a beginning SG of 1.097. I also used EC-1118 and tested it and it was good in the starter. Any ideas? I've let the must open ( towel covered) to air and stirred a few times a day to ensure enough O2. Any ideas? Thank you.