From the National Center for Home Preserving:

http://www.uga.edu/nchfp/how/can_03/tomato_intro.html

I stand corrected: Lemon juice is required for both canning methods. Sorry about that.

Peppi

PKramer wrote:From the National Center for Home Preserving:

http://www.uga.edu/nchfp/how/can_03/tomato_intro.html

I stand corrected: Lemon juice is required for both canning methods. Sorry about that.

Peppi

Nothing to be sorry about. This discussion reinforces this issue and keeps us all on track.

Regards,

Canned another 8 lbs. of romas last night. Process was derailed because one of my jars exploded during processing. I didn't hear it, so it was less an explosion and more of a dismemberment - the bottom of the jar very neatly detached from the rest; the top remain sealed. Any ideas what happened? I think the jar not in there securely and turned upside down and the pressure blew off the bottom. Anyhow, the remaining jars seemed fine.

I recieved the following response from the USDA, after pointing out the conflicting information on the site:

Dear M,

The advice from your canning friend is correct. Even though you pressure-canned the tomato sauce, bottled lemon juice was necessary to ensure the safety of the final product. I would discard the product.

Bummer.

OK, the USDA is no help, I sent a reply noting that the tomato sauce recipe doesn't include an acidifier and got this response:

At 06:25 PM 9/15/2009, you wrote:

Thanks for your response - You should note that the recipe on your site for spaghetti sauce without meat does not list lemon juice or an acidifier; it should be updated if this is a safety issue.


Dear M,

The spaghetti sauce recipe is correct, but tomato sauce is different and needs the acid; I'm not sure why, but perhaps it's the sugar in the spaghetti sauce that makes the difference.

Mhays wrote:I recieved the following response from the USDA, after pointing out the conflicting information on the site:

Dear M,

The advice from your canning friend is correct. Even though you pressure-canned the tomato sauce, bottled lemon juice was necessary to ensure the safety of the final product. I would discard the product.

Bummer.

Cathy 1, USDA 0

=R=

aschie30 wrote:Canned another 8 lbs. of romas last night. Process was derailed because one of my jars exploded during processing. I didn't hear it, so it was less an explosion and more of a dismemberment - the bottom of the jar very neatly detached from the rest; the top remain sealed. Any ideas what happened? I think the jar not in there securely and turned upside down and the pressure blew off the bottom. Anyhow, the remaining jars seemed fine.

Thermal shock is likely the cause.

Did you raw pack the romas or were they put into the jar warm? If they are raw packed with the jars at room temperature, then the warm water in the pressure canner shouldn't be near boiling.

You can also run into thermal shock issues by introducing cold water when everything is really hot.

Last year, I dropped the glass lid to my stock pot. I did a thorough inspection looking for hairline cracks. I saw nothing. A month later, I made stock. Everything was pretty hot. I took the lid off and placed it into my cold stainless steel sink. I heard a funny noise, then watched my lid break into fragments. I knew immediately it was related to the dropped lid incident. The thermal shock finished off the lid.

Stuff like this happens from time to time. It does make a real mess of the canner or pressure cooker. Fortunately it is a fairly rare occurance.

Regards,

For those of you who may be interested in a more scientific approach, I asked my brother-in-law, a chemical engineer, if he could recommend a ph tester that would work on tomato sauce. He found these, which test PH from 0-12, and which "even works with sludges and colored liquids," according to a review on the linked site. I'm thinking $15 is a small price to pay for a lifetime supply of tomato-testing.

Mhays wrote:For those of you who may be interested in a more scientific approach, I asked my brother-in-law, a chemical engineer, if he could recommend a ph tester that would work on tomato sauce. He found these, which test PH from 0-12, and which "even works with sludges and colored liquids," according to a review on the linked site. I'm thinking $15 is a small price to pay for a lifetime supply of tomato-testing.

I could very well be mistaken but doesn't the pH change over time? If so, that would make checking at the time of canning not entirely useful.

=R=

HI,

I just add the lemon juice and never have to think twice about that judgement call.

Regards,

Mhays wrote:For those of you who may be interested in a more scientific approach,

Mhays - I'd first ask the USDA whether those kits are reliable in determining whether you can omit additional acid when you can tomatoes. I'm not sure testing ph at a certain point of time is a substitute for the comfort of additional acid (and I think ronnie may be right about the ph changing) . . .

aschie30 wrote:

Mhays wrote:For those of you who may be interested in a more scientific approach,

Mhays - I'd first ask the USDA whether those kits are reliable in determining whether you can omit additional acid when you can tomatoes. I'm not sure testing ph at a certain point of time is a substitute for the comfort of additional acid (and I think ronnie may be right about the ph changing) . . .

Pickled products like Bread and Butter pickles eaten fresh from pickling are pretty sharp. They recommend they are best eaten after six weeks, because the vinegar does mellow.

Regards,

ronnie_suburban wrote:I could very well be mistaken but doesn't the pH change over time? If so, that would make checking at the time of canning not entirely useful.
=R=

I'm not an expert, just took some chemistry classes in college, but I cannot think of a reason why the pH of substance in a sealed container should change over time. I'm curious now, though, so I'll do some googling and report back if I find anything.

Katie wrote:

ronnie_suburban wrote:I could very well be mistaken but doesn't the pH change over time? If so, that would make checking at the time of canning not entirely useful.
=R=

I'm not an expert, just took some chemistry classes in college, but I cannot think of a reason why the pH of substance in a sealed container should change over time. I'm curious now, though, so I'll do some googling and report back if I find anything.

The acid could be reacting with other components of the mixture, such as the cellulose in the cell walls of the fruit or veg-- this will break the cellulose to sugar molecules, so it might get sweeter, although probably not noticeably. I remember a similar reaction with a tiny hydrochloric acid spill and my favorite jeans back in college!

I agree with Cathy2 that the butter and sugar pickles definitely mellow-- I almost trashed my first batch, but three months later my friends were fighting over them.

Cheers, Jen

Hi,

The romance has been hot and heavy this last week.

I canned just over half a bushel of peaches in a medium sugar syrup (8.25 cups water to 3.75 cups sugar) yielding nine quarts. One jar did not seal correctly, which went into the refrigerator for immediate consumption.

Peaches are very straight forward to deal with if you buy a freestone or cling-free varieties. Freestone or cling-free refers to peaches whose stone detaches easily. A cling peach is a no-win situation if you want nice neat peach slices. A cling peach will force you to slip a knife between the peach and the stone to detach. A jar of cling peach slices looks very raggedy, though no affect in the delicious taste. By contrast, a jar of cling-free slices looks like a blue ribbon champion. Simply gorgeous.

Once the peaches were done, I thought I was done canning for a while. My hope was dashed when my family was offered to pick Concord grapes at a friend's home. My Dad went there feeling quite ambitious. He returned home with only five bushels of Concord grapes on the stem with leaves mixed in. Once stemmed, these grapes weighed roughly 50 pounds. My plans for Saturday vanished because they needed to be promptly preserved. (The late night staff at my local Jewel is a pretty chummy group. They can still be tittering over a customer incident that happened hours before.)

What did I make:
- Seven zipper bags filled with 2 cups + 2 tablespoons of Concord grape pulp for pies.
- 25 half-pints of Concord grape jam
- 3.5 gallons of Concord grape juice (still in progress) - in fresh grape juice there are naturally occuring tartrate crystals. Once formed, they are easily filtered out with a coffee filter or through cheesecloth layers. This is a necessary step, because these crystals may promote kidney stones.

What did I learn:
- How to separate pulp from skins faster. When you are doing a small quantity, squeezing between your fingers is a pleasant activity. When you have lots and lots of grapes, you need a process. I found if I took a comfortable handful of grapes, squeezing my hand closed caused the pulp to pop out between my fingers. Once my hand was opened, I picked out the skins and dumped any remaining pulp into a waiting container.
- Latex gloves preserves your hand's color. I did not have purple hands. I had black stains under my fingernails and cuticles. I looked like I had The Plague or Frankenstein's hands. I was at Jewel buying brown sugar at 10:30 PM. I stood in line, realized the staff would have a field day once they saw my hands. I opted to check myself out to avoid their comments.
- One of my very first canning projects long ago was grape ketchup. I prepared it as instructed: cook the grapes in water, then put through a sieve to separate the skins and seeds. I used a foley food sieve, which managed to chip the seeds. Those chips managed to pass through the sieve and caused a gritty product. I did not rely on a sieve. Instead I separated the pulp from the skins, then boiled the pulp to get the seeds.
- I could see a film of pulp still clinging to the seeds. I found by smartly rapping the sieve on the edge of the bowl, the pulp flung down into the bowl. I pretty much collected almost all my pulp with great ease.

My grape catsup recipe was adapted from The Best of Shaker Cooking by Amy Bess Miller and Persis Fuller:

Amelia's Grape Catsup
North Union Shaker Village, Ohio

5 pounds grapes, stemmed (10 cups)
1 tablespoon ground cloves
1 tablespoon cinnamon
1 tablespoon pepper
1 tablespoon allspice (I used nutmeg, instead)
1 teaspoon salt (I skipped it)
4 cups maple or brown sugar (I used brown sugar)
1 cup best wine vinegar (I used apple cider vinegar)

I separated pulp from skins as described above. I gently boiled the pulp to free seeds. I pass the pulp through a coarse screen sieve. Returned pulp to pot, added skins and remaining ingredients. Once the skins were softened, I used a wand blender to chop and pulverize them. I did leave some chopped skins in for texture. Boil gently until thick.

Pour into clean jars 1/2 pint jars, remove any bubbles, clean rims, leave 1/2 inch space and add lid. Process in a boiling water bath for 10 minutes.

I made two batches. I had intended to make grape jam or butter, then changed my mind once I tasted the catsup. The first batch is thicker than the second, largely because I was ready for bed and didn't want to wait longer.

It will be great on ham or turkey later this winter.

Regards,

Hi,

Through Daily Candy, I ran across a blog called Salted Caramel. I was reading her post on preserving and immediately though of you, Cathy. She "demystifies" the process by claiming that, among other things, you do not need to immerse the jars in water for processing. I thought that it was a necessary step for killing bacteria, and I know there are supposed to be other reasons as well - but I am no expert, and thought I'd turn to those who are for some thoughts. Here's the link to her post:

http://www.floraconfections.com/2009/07/4-big-myths-about-jam-making.html

I do like how she points out that you can't really reduce sugar in a lot of recipes without affecting the shelf life. It's a useful tip that is easy to overlook in these days of "low carb" everything.

Cheers,
Katherine

Hi,

I read that link with visible steam coming out my ears.

If you are in an industrial food environment with autoclaves, time-heat penetration studies, refractometers and a food scientist available to you. Go for it!

My baseline for all my canning activities are the USDA regulations that provides research based information on home canning methods. Literally millions of dollars and thousands of hours spent that can hardly be tossed off as conventional wisdom.

I not only use their canning guidelines for headspaces (necessary to create a vacuum)and processing methods. I also used their recipes to gauge if there is enough sugar, salt and acid in recipes I see elsewhere.

When I took the 60 hours of classes (plus 60 hours of volunteer payback) related to this topic, I did not initially appreciate the high level of education I received. I appreciate it more and more when I see so much shooting from the hip related to preserving that really call into play quite a bit of science: biology, chemistry and physics. This is not an effort to get all artsy fartsy and do whatever inspires at the moment, unless you really, really know what you are doing.

The USDA has studied and eventually concluded it was unsafe to:
- steam process home preserved products
- oven process home preserved products
- fill jars with hot jam and flip them upside down "to process" while cooling
- parafin to seal jars
- oil to seal jars

I talked to someone this summer who took a class at the French Pastry School from Christine Farber. They used the oven method where the jars were heated in the oven for several hours to seal. Most waterbath processing times for jam are less than ten minutes in sterilized jars. If you don't use pectin, which breaks down in prolonged heat exposures, you can skip sterilizing the jars if you process for ten minutes or more in a water bath. Instead of hours, it was really minutes to do it safely (and efficiently). I could see a glimmer in this person's eyes they had now come to agree water processing was no big deal.

One evening, I read of someone making bacon jam that they waterbath processed. I advise this was pretty dangerous, because processing of any meat product requires pressure canning. The pectin used would wilt long before reaching 240 degrees F for processing. I suggested this product would be best treated as a freezer jam. They decided to keep it in the refrigerator and hopefully used it in fairly short order.

I thank my lucky stars I was taught what I know by Linda Eilks , a former U of I Extension educator, who followed strictly the course guidelines written by Susan Brewer, PhD at the University of Illinois.

At my suggestion, there were several Master Food Preserver conferences in Champaign. The faculty never believed anyone would attend. There was room for 35 people, it filled immediately with a waiting list. In the early 1990's, it was believed home canning was a dying discipline. Eventually Susan Brewer departed from the Extension when they whittled her budget to less than $1,000.

When there was a "Best of Midwest Farmer's Market" at Ravinia, an Abby Mandel inspiration pre Green City Market, I was there representing U of I Extension. I collected over 150 names interested in learning to preserve food. I am certain the list would far longer today.

Clearly there is a growing interest, what is sorely lacking is educational resources for people who want to learn.

Regards,

Wow. Blast from the past. I worked with Linda Eilks briefly after she left U of I.

Because of the sorrowful state of U of I Extension, I always turn to UW (which unfortunately has been having its own budget problems in recent years).

How Safe Is Home Canning

This article gives you an idea both of how serious it is and how it's possible to can safely without going crazy. I'm not at all flippant about the rules, especially since the toxin we're talking about is botulism, here - which doesn't just give you gastrointestinal issues; we're talking probably fatal paralysis. That being said, it's important to note that the documented cases of botulism poisoning, while linked to home canning, involved low-acid foods like meats and vegetables like asparagus - that were improperly canned.

I understand and agree with why the USDA is so strict about the guidelines for home canning, and I want to make sure everyone knows that I'm not questioning the established rules - I had questions about some inconsistencies in the existing guidelines on tomatoes.

Cathy2...have you ever thought about teaching this subject? You seem more than qualified!

MHays,

My comments were not directed toward you. Did you read the link that sent me into a tizzy? I popped a few white hairs with that one.

teatpuller,

You know Linda, too, that's cool.

razbry,

I have been helping people here and there. I am trying to encourage Jarden/BAll to do a class in the Chicago area next year.

Regards,

No, I understood, Cathy - I just wanted to make sure I was clear out there on the internet - the article I posted shows why (and directly shows the consequences of why) one needs to follow the rules. I liked that they mentioned even the NYT had to retract a garlic in oil recipe by Mark Bittman for food safety reasons, mistakes are very common.

Cathy--- Where on earth do you store all of your loot? What is your thought about creating an anarobic (sp?) environment when submerging veggies (like the garlic thing mhays was referring to) in oil? How do they do it in Italy?

Next year, I want to hit it better with my cherry preserves. Any suggestions for getting a thicker product? I do not use any commercial pectins (only apples) and worked with Christine Ferber's style this year and decided she makes me crazy.

I also had to foley mill my delicious apricot jam for the second year in a row. Mick Klug has no idea why the apricots of the last two years have membranes running through them that are so hard --delicious flavor but not yielding the texture I prefer. Anyone else have that problem?

This thread is inspirational!
I was the lucky recipient of a large number of vintage canning jars. Unfortunately, many of the jars are covered in some sort of white film, maybe minerals or soap scum. Is this bad for my canning? Any tips on getting it off?

Thanks, Jen

JenM wrote:I was the lucky recipient of a large number of vintage canning jars. Unfortunately, many of the jars are covered in some sort of white film, maybe minerals or soap scum. Is this bad for my canning? Any tips on getting it off?

According to my Ball Blue Book of canning, "older-style canning jars once suitable for home canning should no long be used for this purpose. Many jars cannot be properly fitted with two-piece vaccuum caps, and new closures of original design are not available." Keeping in mind that Ball is in the business of selling jars as well as teaching canning, I take that advice to mean that "older-style canning jars" can be used as long as they can be properly fitted with bands and vacuum seals or if the closures of the original design are still available. Also, the jars should be free of knicks, cracks or other defects which may cause the jar to burst during processing.

Also according to my Blue Book, as for cleaning the white film (which is caused by mineral deposits), rinse the jars and soak them in your canner with a solution of 1 c. white vinegar to 1 gal. water. If the white film still doesn't come off, then it might be due to etching in the glass. You can also add 1/4-1/2 c. vinegar to the water during processing to help avoid film build-up.

Thanks for the tips on removing scum! The jars are vintage, but not that old-- they will still fit with the regular lids and bands.

Cheers, Jen

Jen,

Do you have a picture of the jars? It will go a long way to understanding what you have.

I have been the happy recipient of canning jars from people retiring from this duty. Most of the jars have been quite useable and others hold dried beans and leftovers.

As aschie said, it is important they be inspected for chips and cracks. I run my finger over the lip of every jar everytime I use it. A few times, I felt chips I did not visually detect. Any rim chip will contribute to a jar not sealing. If the lip is too broad, I retire it to non-canning use.

A canning jar is good for six runs. Since most of my jars are inherited or purchased at rummage sale, I have no clue on their useable age. I stopped worrying about it long ago when I realized I could never keep track.

Mayonnaise and most commercial jars are intended for single-use. People use them for canning, if they fit the lids and rings. I have largely given up on those, because their thinner walls made them more likely to break. A few spaghetti sauces are jarred in containers with mason jar characteristics. I will use those, though they are often a non-standard size, i.e. hold 3-cups instead of a pint or quart jar.

When a jar fails, the loss is just not the jar. It is your time and money going poof, too.

Regards,

The only jam I am willing to put up any more is damson plum. I love it. For any of you who agree with me, I found damsons on sale today at Fresh Farms on Touhy for $2.49 for 40 oz. Don't know where they're from--they're clearly repackaged in plastic clamshells originally for cherries. In the past I've found them at some farmers markets and even, pre-Safeway, at Dominick's. I bought 3 boxes and will make the jam tomorrow or Monday.

Tomatoes: how I do it

(Keep in mind, I have no professional experience or reason to do this, and the method is mostly stolen from Jacques Pepin, except he blanches and peels first, and I prefer to scorch-and-peel after: I like the caramalization and I think - very unscientifically - that blanching adds water where I'm trying to get rid of it)

Step 1: Thoroughly wash tomatoes


(OK, you didn't need a visual, but I'm proud of that pic. Besides - note that I'm using "field tomatoes" bought cheaply in bulk from the Evanston farmer's market: after cooking, these have as good flavor as any I've found. I prefer big field tomatoes for this process over small Romas, which have less liquid but are more fiddly and often a bit mushier.)

Step 2: Turn your tomato stem-end down and cut off an outside "petal" as shown. Repeat for remaining 3 sides. Make sure you leave the little belly button, or the skin will stick to it.


Roma tomatoes can be processed similarly by removing the entire outside in one long strip like this, kind of sliding your knife around the core:


Step 3: Using a finger, scoop any remaining seeds from the "petal" into your stock pot and set the petal aside. Cut your tomato core into large slices, including any skin, bellybuttons, stem end, etc. and place in stock pot as well.


Step 4: Place the petals in a single layer (important, if they overlap the skin will stick to the tomato where it's sheilded from heat) on an olive-oil lined baking sheet. Place in the broiler for about 5 minutes or until you smell caramalization, remove when the skins are blackened as shown below (earlier is better than later.) The skins should pull off easily. Dump the remaining petals into a bowl and set aside.


Step 5: Place your pot of tomato cores, seeds, guts, - I even add the blackened skins sometimes - on the stove and simmer until it starts to dissolve and all becomes glop - then turn off the heat. Cool slightly.


Step 6: (OK, this really isn't so complicated that you need all these steps, but I've got all these pictures, see?) The next step is to strain out all the seeds. I first tried a cheap food mill from Harbor Freight that did absolutely nothing except get some seeds in my juice, so I went back to tried-and-true mashing it through the strainer with the back of a ladle. This should be relatively easy if the tomatoes are ripe and things are well cooked - and the bitterness stays with the seeds that are strained out, no worries. Discard seeds, skins and cores - the second-to-last photo shows everything I discarded from 20lbs of tomatoes. Put the juice on the stove and simmer to reduce until you have something a bit closer to sauce.


Step 7: Add your reserved peeled tomato petals and continue to simmer until you're happy with the viscousity.


You wind up with the base for a very nice tomato sauce. Usually at this point, I've lost my vim and vigour for the day, so I quick-chill it, refrigerate and then bring it back up to a boil the next day before adding seasonings and finishing the sauce for canning. I like the black flecks you get from the tomato skins...

Mark Bittman's blog at the NY Times had a nice piece (not penned by Bittman) a few days ago about the tomato canning ritual of an Italian-American family in Staten Island.