Dear all , as mentioned on the topic , I faced an issue when the jam (aw0.5)deposit on the cookie ，it turns really soggy after 3-4 months where I expected to stay crispy for a year. Any possible ways to keep my cookie baked from the oven retain same aw as jam? Does it relevant to the biscuit recipe ? Kindly advise thx
It is important to equilibraré both the base cake Aw and the jam Aw. Both formulations needs to be reviewed and balanced. Unbalanced aw may be one of main causes moisture is migrating loading the crispy texture on the base. If interested in discuss further details please send a note to my e-mail.
Roberto mentioned about a cake base, but I guess you meant a cookie not cake.
To solve your problem, you need to work on different fronts:
1- Aw is certainly very important and need to be matched or brought as close as possible, however, it will not help you if your Jam is not stable.
2- Jam stability: Some Jams are not stable, if I recall well, Xanthan added to Jam will help to stabilize it. Important to ensure that your Jam is stable, I worked with Puratos Jams and got good results.
3- Condition your biscuit prior to deposit the Jam, gaining few % moisture is very helpful, I will be using a rich recipe, not lean.
4- Storage conditions: This is also very important to ensure proper shelf life.
I suppose that your cookie has indeed a significant low Aw and that moisture from the filling is migrating into the cookie. Depending on your formulations you can design the cookie and jam to some extent delay this migration. However wanting your cookie to remain crispy for 1 year will probably result in designing you jam to Aw of close to 0,35.
0.5 is too much, try max 0.4 Aw. Manufacturers use water binding ingredients to make these low Aw jams, so the recipe can be adjusted to achieve the desired Aw.