# Telling Jams Apart -- Need Help Fast **URL:** \ **Category:** Factual Questions\ **Created:** [December 11, 2023, 9:23pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446 "2023-12-11T21:23:37Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![anny\_m](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@anny\_m](https://boards.straightdope.com/u/anny_m)\ **Post date:** [December 11, 2023, 9:23pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/1 "2023-12-11T21:23:37Z")
OK, I got really stupid. A couple months ago I made jam for Christmas presents. Two types I made were Cherry – made from dark sweet cherries – and Blueberry Marmalade – blueberries with lemon and orange flesh and finely chopped zest. So where I got stupid was that I didn’t keep the two jams separate. Now that I’m ready to label them, I can’t tell them apart. With the exception of a couple of jars that have a sliver of citrus peel near the glass, they look to me identical. I could open the jars, separate by type, and re-can them, but this would likely affect the quality of the jams. Any other ideas? I’ve been meaning to purchase Photoshop Elements anyway, so if there’s a way that would help I’ll do so now. Is there any other (not really expensive) software that could help? Any special lamp I could easily get? ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [December 11, 2023, 9:34pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/2 "2023-12-11T21:34:30Z")
Don’t have no clue what your last paragraph means. At all. But, I would NOT open the jars. Unless you intend to refrigerate after. Can you give them as a gift and call them “Surprise Jam”? If they’re for your own use. Take your chances. ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [December 11, 2023, 9:39pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/3 "2023-12-11T21:39:12Z")
I would totally make labels that say “50/50 chance at cherry or blueberry” maybe with a little picture of dice or a hand of poker cards. Call your gifts “Jam Roulette.” ---
**Author:** ![anny\_m](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@anny\_m](https://boards.straightdope.com/u/anny_m)\ **Post date:** [December 11, 2023, 9:43pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/4 "2023-12-11T21:43:40Z")
They are for gifts. I was hoping that I could take a picture of a jam and then use Photoshop Elements or other software to tell a difference in the color my naked eye can’t discern. Or possibly use some kind of light that would accentuate the difference. There’s gotta be some kind of science way to tell them apart, no? I could open the jars, determine what variety each is, put all of one kind in a pot, bring to boiling, put in clean jars and reprocess to can them again – but I’m pretty sure the quality would suffer. I have 15 jars I can’t tell the difference, plus 22 jars of other kinds of jam I can tell what they are. I’m giving 11 gifts of 3 jars each. I’m considering just making 11 jars of some other type, but I hate to have to do it. It’s not like I don’t have other stuff to do this close to Christmas… ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [December 11, 2023, 9:52pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/5 "2023-12-11T21:52:44Z")
Wow. You can buy an egg candler light. I bet you can see the zest with that. Good luck. I’ll pm you my address, I’ll take surprise jam😁 ---
**Author:** ![needscoffee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/needscoffee/32/1076_2.png) [@needscoffee](https://boards.straightdope.com/u/needscoffee)\ **Post date:** [December 11, 2023, 9:57pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/6 "2023-12-11T21:57:48Z")
Can’t you hold it up against the brightest lamp/flashlight you have and look for clues? ---
**Author:** ![Treppenwitz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/treppenwitz/32/3445_2.png) [@Treppenwitz](https://boards.straightdope.com/u/Treppenwitz)\ **Post date:** [December 11, 2023, 10:00pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/7 "2023-12-11T22:00:11Z")
Is there a significant difference in the set of the two jams? Warm the jars slightly and see if one type is significantly more mobile than the other? j ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [December 11, 2023, 10:47pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/8 "2023-12-11T22:47:21Z")
> [@needscoffee](#): > > Can’t you hold it up against the brightest lamp/flashlight you have and look for clues? That’s what I thought of, too, and I’ll add that OP’s brightest lamp may be a vehicle’s headlight. ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [December 11, 2023, 11:11pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/9 "2023-12-11T23:11:11Z")
“No! Occifer, this definitely ain’t moonshine in this here jar!” Do the car headlights in your garage. I read a bit, egg candlers prefer doing the candling in a darkened room. For reasons, I guess. ---
**Author:** ![Elmer\_J.Fudd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/elmer_j.fudd/32/1211_2.png) [@Elmer\_J.Fudd](https://boards.straightdope.com/u/Elmer_J.Fudd)\ **Post date:** [December 11, 2023, 11:19pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/10 "2023-12-11T23:19:47Z")
Might there be a difference in weight? ---
**Author:** ![anny\_m](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@anny\_m](https://boards.straightdope.com/u/anny_m)\ **Post date:** [December 11, 2023, 11:21pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/11 "2023-12-11T23:21:28Z")
I’ve decided to label the jars “either/or” and explain in the accompanying note card (which gives ingredients) that it’s a mystery jam. My attitude is, “Well, the hell with it. They oughta be f-ing delighted they are getting homemade jam at all. \” My Christmas spirit is in short supply this year. ---
**Author:** ![thelurkinghorror](https://avatars.discourse-cdn.com/v4/letter/t/7c8e57/32.png) [@thelurkinghorror](https://boards.straightdope.com/u/thelurkinghorror)\ **Post date:** [December 11, 2023, 11:21pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/12 "2023-12-11T23:21:44Z")
Sure, there are devices like colorimeters that could characterize the jam, but that’s a hundreds to thousands dollar purchase that’s unnecessary. Instead you’d want to use a bright light that provides enough broadband light to compare the two types of jam effectively. Fluorescent type bulbs are not ideal, an LED may or may not be useful, if you can find the manufacturer’s published spectral data that’s ideal, look for a plot that is relatively flat against the Y axis. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [December 11, 2023, 11:26pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/13 "2023-12-11T23:26:45Z")
> [@anny\_m](#): > > My attitude is, “Well, the hell with it. They oughta be f-ing delighted they are getting homemade jam at all. \” Personally, I’d be happy. ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [December 11, 2023, 11:38pm UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/14 "2023-12-11T23:38:10Z")
The gift that keeps supplying surprises well after Christmas. I like it. ---
**Author:** ![Aspenglow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aspenglow/32/76_2.png) [@Aspenglow](https://boards.straightdope.com/u/Aspenglow)\ **Post date:** [December 12, 2023, 12:25am UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/15 "2023-12-12T00:25:14Z")
I don’t have any suggestions for how to tell the jam apart now, but what I would suggest for next time is to use jars that are different from each other. Maybe ball-shaped jars for the cherry and taller, more cylindrical jars for the blueberry. Both jams sound lovely, no matter how they’re housed. For now, I love @purplehorseshoe’s clever suggestion to just embrace the boo boo and make it part of the fun. Your loving friends and family will get a kick out of learning you’re as human as they are! They will enjoy the jam surprise, too, I’m sure. Is anyone really that picky about which jam goes on their scone/biscuit/pancake/toast? Not me! Homemade jam always rocks! ---
**Author:** ![iiandyiiii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iiandyiiii/32/7924_2.png) [@iiandyiiii](https://boards.straightdope.com/u/iiandyiiii)\ **Post date:** [December 12, 2023, 1:02am UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/16 "2023-12-12T01:02:08Z")
Could you make the jams again and see what they look like? Maybe there’s a noticeable difference. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [December 12, 2023, 1:59am UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/17 "2023-12-12T01:59:17Z")
While I endorse the gambler gift bit you do have one identified. Maybe it upside down to get a thin layer sticking to the bottom glass now on top and see which ones match that thin bit in color? ---
**Author:** ![don\_t\_ask](https://avatars.discourse-cdn.com/v4/letter/d/e68b1a/32.png) [@don\_t\_ask](https://boards.straightdope.com/u/don_t_ask)\ **Post date:** [December 12, 2023, 6:52am UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/18 "2023-12-12T06:52:25Z")
I would go with the “Surprise Jam” approach. However, I would supply 2 printed labels and guarantee them that I will, at a future Christmas, supply them with the jam that they didn’t get this time. ---
**Author:** ![InternetLegend](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/internetlegend/32/13154_2.png) [@InternetLegend](https://boards.straightdope.com/u/InternetLegend)\ **Post date:** [December 12, 2023, 6:59am UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/19 "2023-12-12T06:59:44Z")
I pay a ridiculous amount of money every year to have the good folks at Bonne Maman send me an Advent calendar filled with tiny jars of surprise jam. If any of your friends dares to complain about it, send me their jam! I’ll pay packaging and shipping. ---
**Author:** ![pjd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pjd/32/3009_2.png) [@pjd](https://boards.straightdope.com/u/pjd)\ **Post date:** [December 12, 2023, 10:14am UTC](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446/20 "2023-12-12T10:14:44Z")
You could label them Cherry Jam (Warning : May contain blueberry marmalade) and Blueberry Marmalade (Warning : May contain cherry jam) > [@InternetLegend](#): > > Bonne Maman send me an Advent calendar filled with tiny jars of surprise jam Isn’t that different (the jars inside the doors are labelled) ? [Next page](https://boards.straightdope.com/t/telling-jams-apart-need-help-fast/994446.md?page=2)