From: Linda Magee
Newsgroups: rec.food.cooking
Subject: JAR CAKES-Query/Answers
Date: 03 Jan 96

QUERY: EXPLODING JARS

>I only have one problem with it...the canning jar companies DON'T want people baking in their jars and won't guarantee the jars won't explode etc. when in the oven.

>At one time the Kerr Co. did hire a person to develop several recipes to be used with their canning jars...can't remember his name offhand...would have to look it up. I contacted him to see if he could give me any pointers but wouldn't even answer my letter. That didn't slow me down much as contacted Kerr Co. again and tried some more. Also did contact the man that developed recipes for them once again...used a SASE this time but still no reply. Kerr did send me the recipes they did publish BUT did not recommend doing these recipes in canning jars any longer!

>Do believe both Kerr and Ball Companies felt that baking in canning jars is just too high a risk for them to offer any information. The testing and recipes that were available from Kerr Co. were done in the late 1970's and early 80's. Gather from Kerr rep. that there were 'situations' that came up after this method was released and they have since dropped it and advising not to can bread in their jars.

MY RESPONSE:

I, too, contacted the Ball and Kerr Jar companies when I first started baking the cakes (almost 10 years ago) and got the same response..."WE DON'T RECOMMEND" baking cakes/breads in jars.

Of course they aren't going to condone anything they've not successfully made themselves. I KNOW they didn't use the method I use, otherwise they wouldn't have made the, "explode in the oven" comment. The jars aren't sealed in the oven, only baked. I can't fathom what they were even thinking. Hmmm, besides that, their jars can withstand the pressure and heat of pressure canning, so they surely can handle the heat from the oven. Again, they don't know, and they've not really tried the method I use, otherwise they'd have never made that statement. Duh. :}

One fellow Net person sent 6 jars of quick bread to Puerto Rico--they made it there just fine. I'm sure they were shipped in the cargo section of the plane and I doubt that compartment is pressurized. If anything were going to burst the jars, that would do it. I'm sure it took quite a while for the jars to arrive too. They arrived safe and sound--no one died from ptomaine poisoning or shards of glass. :)

QUERY: GREASING JARS/STERILE?

no, I didn't wait until the jars were completely cool before greasing them. I was afraid it would make them unsterile again.

MY RESPONSE:

Sorry for omitting this when I posted the recipes. I just DO it, don't even think about it. I always sterilize the natural bristle brush I use to grease the jars with (don't use a synthetic brush--they melt!) and the tongs I use to handle the jars. I put them in with the jars, lids and rings and boil it for 15 minutes, then put them out onto the clean towel to dry a bit. The brush doesn't have to get completely dry, just so it's not sopping wet. You can blot it on the towel to remove as much moisture as you can. The little bit of moisture left doesn't affect the cakes when baking, it will evaporated (or make the cakes moister). Also, because the jars are baked (after being washed in hot soapy water, then boiled), it just furthers the sterilizing of the jars. It gets hot enough when they're baked to kill any bacteria that might be left on the jars after greasing. I've been baking the cakes in jars for about 10 years now and have never poisoned anyone, so I think we're doing things as safely as possible.


QUERY: CAKES STICKING

>I had a problem getting the cake out of the jar, it stuck badly. What did I do wrong? Was it because I greased the jars while they were too hot?

MY RESPONSE:

Well, it sounds like the place where you stored the cakes was plenty cool, that's why the cakes stuck. The shortening hardens once it gets cold, so you need to warm the jars up before attempting to get the cakes out. I usually try running the unopened jar under hot water, then taking it out. If the cake is REALLY cold, you might want to take the lid off then pop the jar into your microwave for 30 seconds or so, that'll loosen up the shortening and the cake should slide out. Warm gingerbread is great. :) Also, greasing the hot jars, the shortening may have run down the sides of the jar and you missed getting it all over--doubt that was the problem though.

QUERY: JAR HANDLING/TEMPERATURE

>Was told that the critical stage of possible breakage was at the time the oven door was opened (cold air as a shock to the very hot glass jar), picking the jars up to place them in an area for cooling, handling the hot jars to place the lid on them. I tried completely wrapping each jar in a terrycloth towel when removing it from the oven. I placed the towel wrapped jar on a towel covered wire cooling rack. Really being very careful with each jar and trying hard not to bump or get it touching something cold. Was kind of a pain really. Had to plan where each jar was placed on the baking sheet when you set them in the oven...really needed to have wits about you when doing this whole process.

>Using an oil, crisco or veg. spray on the inside of the jar will cause the jar to really get hot as it bakes. I did set the jars that I experimented with on an air cushioned baking sheet for further insulation. I did experiment using yeast breads also...not just quick breads. The recipes that I received from Kerr were only quick breads.

MY RESPONSE:

The baking temperature (I make a BIG note of saying NOT to put the oven any higher than 325-degrees for a reason) has a lot to do with it too. Of course if you get a jar too hot (greased or ungreased), then expose it to cold air, it could cause a problem. The jars are hot, but not that hot to where that would be a problem. I've been baking the cakes in jars for over 10 years and have never had a problem with the jars breaking, exploding or spoiling. That's why folks need to pay attention to ALL the details in the recipes I give. I take ONE jar at a time from the oven--put a lid and ring on it (using HEAVY-DUTY mitts!), then place the jars on a doubled-over towel. If I were to put them onto my cold counter top it might cause a problem, but I've yet to experience any. Terry cloth towels are too flimsy, you can burn yourself! That's another reason I say to use HEAVY-DUTY MITTS! Dish towels just aren't thick enough--the jars (mainly the metal rings) DO get HOT.

Dealing only with one jar at a time, it's almost impossible (this side of dropping it or burning yourself) to experience any disasters. The other jars need to stay hot, so they don't lose the steam they need to help with the sealing process. I never take all of the jars out, then seal them for that reason. Close the oven door while you work on sealing one jar.

I never mentioned putting the jars onto a rack to cool--that would make them very unstable and I would surely dump the whole mess on the floor. A heavy bath towel on a flat counter top will ensure that they stay put and don't bang around on the counter or against each other and would insulate them from the cold counter.


Editor's Note:
Please be cautioned that no matter what you may read on the web about storing cakes in jars that the seal does not make them a 'canned' product. Info from the National Food Safety Database:

Canning Breads and Cakes
Angela M. Fraser
Canning breads and cakes is not true canning. It is the process of baking the product in canning jars and capping them as they come out of the oven. Usually, a weak seal will form as the product cools. This is not a shelf-stable product and so must be stored in the refrigerator or freezer to prevent microbial growth.

Title: Jar Cakes
Posted By: Rochelle, CA
Date: July 7th 2001
Board: recipelink.com Canning and Preserving

It is not recommended that jar cakes be kept longer than a couple of weeks and even then they should be refrigerated or frozen. The temperature in the batter doesn't get high enough and it doesn't penetrate the batter sufficiently to prevent bacteria from growing.