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cabrita_gw

Using a pH meter and lowest pH to kill botulism

cabrita
14 years ago

I have a basic canning/pickling question. Many questions really, but just one today.

I understand that the way pickling works is by reducing food pH so botulism and other nasties cannot live in the food. A quick google search gives me pH 4.8 as the lowest that can host botulism. Does this mean that as long as I achieve pH 4.7 or lower, I am save just using BWB canning? or even just refrigeration?

I recently got a pretty accurate pH meter (SPER scientific large display pH pen). I have been using it for garden soil samples, but it can be cleaned well. I am also going to make/buy a buffer solution to increase the accuracy. I was wondering about measuring the pH of the food prior to canning, both for information/curiosity, and for safety reasons. Do any of you measure pH for canning/pickling purposes?

It turns out I do not like really sour pickles, or really acidic tomato sauces, so I would prefer to stay near the 4.7pH range, allowing 0.2 pH for meter accuracy. I also wanted to confirm that 4.7pH is safe enough. Thanks for your comments and answers.

OK, I said just one question but there is a related one. Since both salt and vinegar are used in pickling, and both have a preservation effect. Is there a way to measure the synergistic effect of both salt and vinegar? like if i use enough salt, I can raise the safe pH some?

Comments (65)

  • ksrogers
    14 years ago
    last modified: 9 years ago

    I think the magic number is 4.0. Yours are OK. To acidfy, try adding bottled LIME juice and cider vinegar. These two add a lot more character to a salsa. You can also use citric too, but because salsa has many facets in taste, its nice to add a few more. I made some roasted chicken using lime juice and my mom had nevr had such a combination. At that time, it was her favorite way to enjoy grilled chicken outdoors.

  • digdirt2
    14 years ago
    last modified: 9 years ago

    IF it is really 3.8 and IF it remains at 3.8 then yes, it would be safe. But those are 2 big IF's. And therein lies the problem. ;) Even commercial pH equipment is constantly re-calibrated and cross-tested so are you comfortable with the readings from your meter? I wouldn't be given the risk.

    And as to stability of pH, that all depends on storage conditions and age. Cool and dry and less then a year - probably. High humidity, brief exposure to heat or inconsistent temps or longer than year - probably not.

    Alternative to dumping - open the jar, boil the contents for 15 mins., re-jar into new jar and into the fridge. I wouldn't but it is up to you.

    Bottom line - no, it can't be guaranteed safe so it is your choice.

    Dave

  • Linda_Lou
    14 years ago
    last modified: 9 years ago

    No,it is not safe. It is not safe to assume it will be. Testing your own foods is like playing Russian roulette with a loaded gun.
    I teach food preservation safety. I would never say this is safe.
    Only tested recipes and methods from a reliable source should be trusted. Ones from the Ball Blue book or any of the Univ. extension sites, especially the Univ. of Georgia are tested and safe. Some other books and info online may or may not be. Trust your safety to those who are trained in the field of food preservation.
    It is too late to reprocess the salsa or trust it. Sorry, that is the safe information. Even if you boil it, you can contaminate the can opener, the counter, a spoon, etc. Get it in a cut, or splash in your eye. You get the idea.
    I would chalk it up to a learning experience and not do this again.

  • chmst1999
    13 years ago
    last modified: 9 years ago

    These posts are interesting, informative, and troubling at the same time. I'm a chemistry professor at a university. It seems strange to hear that "testing your own foods is like playing Russian roulette...only tested recipes and methods from reliable sources should be trusted." Doesn't this raise anyone else's eyebrows? It is becoming more difficult to get high-acid tomatoes, for example, so if we follow a "reliable" recipe but use a hybrid tomato by mistake, we may be inadvertently risking our health. If we "trust" that the vinegar is at least 5% as stated on the label, and it is really 4.3%, we are also at risk. If the water quality your area is slightly alkaline, your water may be neutralizing some of the acid you add, which would then reduce your acid content without even knowing it.

    There are too many variables in your "canning" experiment to simply resign yourself to a "trusted" recipe. Although those are important, I would still suggest a pH meter to add another level of quality control. It is simply naive to "trust" a proven recipe but not use the technology we have available. I've attached a link to a reasonably inexpensive pH probe. Keep in mind, food-quality researchers who test acidity use pH probes and frequently calibrate them. This is no different than checking your bathroom scale to see if it is zeroed before you get on. That doesn't mean the scale is faulty, it just means you set the scale before using it...

    I hope some of this helps.

    Here is a link that might be useful: Large Display Waterproof Ph Meter - Pen Style By Sper Scientific

  • tracydr
    13 years ago
    last modified: 9 years ago

    The alkaline water is one variable that troubles me. Our water is not only hard, it has a high pH. I've wondered about this for awhile.
    Seems as if, someone like Chmst1999 or cabrita would be fully qualified to take an already tested recipe and be even safer by verifying pH with a calibrated, good quality meter.
    I'm not saying they should or need too but it doesn't seem like it would hurt. The difference between 3.8 and 4.2 is enormous so would provide a pretty high safety margin.
    I can also see why, no trained food preservation specialist can recommend this technique, maddening though it is for a highly trained scientist.
    My background BTW, is medical school, Masters in Nutrition and undergrad to include animal science classes up to high level graduate classes. These included food science in a commercial light.
    But, I will still follow only approved recipes, can't quite wrap my head around why pureed sauce can be less safe than chunky, as I read in a recent post.
    Sometimes you have to look at the population that our canning recipes are geared for. They are written for someone with a 6th grade education and have a pretty high margin of safety to account for stupidity.
    Seeing the average level of intelligence of people coming through the ER it's a wonder some people can figure out how to boil water!

  • chmst1999
    13 years ago
    last modified: 9 years ago

    Hopefully, this discussion has given everyone more things to think about. It has for me.

    The more I think about it, the more I believe the water quality is the essential variable to test. Alkalinity causes all sorts of problems. For example, my in-laws all have varying degrees of acid reflux, but it only seems to become a problem when they travel. When they go on a trip and drink "city" water, they always experience acid reflux problems. They always blamed the "city" water and said that the "city" water was giving them heartburn, but that didn't make sense to me. However, when we tested their well water, we found that it was alkaline and had a reasonably high pH (greater than 8.5). Since pure water should have a pH of 7, their well water was acting as an antacid and their bodies were conditioned to produce more acid all of the time.

    Think about what would happen if they canned with their well water using any recipe. There is no way they would be getting their pH as low as necessary without adding significantly more acid.

    Of course, I'm not saying that most people should just make up a canning recipe without sufficient knowledge. I think the recipes account for a lot of variance in conditions. However, a pH meter is a good way to be sure the acidity is sufficient. We tell people to change the cooking time, pressure above the liquid, etc. depending upon elevation, so it doesn't seem like a stretch to tell people to get a pH meter and check the acidity.

  • tracydr
    13 years ago
    last modified: 9 years ago

    Are canning recipes tested with various water pHs to account for these differences?
    I would hope so!

  • foothillfarm
    13 years ago
    last modified: 9 years ago

    I am very disturbed whenever anyone says that testing your own recipes are dangerous. Anyone with a basic chemistry understanding should be able to test a recipe to insure that it is 4.2 before water bath canning.

    I have tested my tomatoes prior to canning and they change every year. Once you start making salsa by adding onions, garlic and peppers, you would have no idea whether it was safe to can without using a pH meter.

    By using an pH meter you can take control of your recipes and make them NOT dangerous. Anything below 4.2 that you cannot add Bottled Lemon juice to (I like Volcano!) or citric acid and lower the pH should be pressure canned or refrigerated or frozen.

    The USDA says this you shouldn't make up your own recipes. They are also the ones who say it is safe for my neighbor to plant GMO corn.

    We don't have to be sheep. Educate yourself. Test your your recipes, be safe, but don't feel like you need to follow every government recommendation. For God sake, Ball is still making lids with BPA in them! I have switched to European lids and I believe they are superior.

    I have been canning for 20 years. I do not can like I did 20 years ago. There is no guessing in my kitchen.

    If you buy a meter:
    Accuracy: This should be the rst consideration. Accuracy is listed as a range of 0.X pH units. This means the meter may read so many pH units above or below the actual pH of the product. Since you will be using or loosing batches depending on the pH reading, a narrow accuracy range is important. Considerations include:

    - For food processors of products with pH between 4.0 and 4.6, a pH meter with an accuracy of ±0.01 - 0.02 pH units is sufï¬cient and required.

    Calibration: All pH meters must be calibrated (checked against a known standard) to assure accuracy. Most meters can be calibrated to at least two standards at the same time.
    - Calibration Standards or Buffers: You should order at least 2 buffers, pH 7 and pH 4, for your two-point calibration. The pH 4 is necessary because your meter should be calibrated to a standard that is no more than 3.0 pH units from your product. Sometimes buffers are sold in sets of 4, 7 and 10. You don't need the 10 to do canning. Remember you are shooting for 4.2.

    Calibration takes time. Canning takes time. If you are going to do it. Do it right. Don't be afraid to re-check a jar after being in storage for 6 months.

  • Linda_Lou
    13 years ago
    last modified: 9 years ago

    So, are you saying YOU are going to carry liablity insurance to cover what you are saying ?? I will not endorse anything not tested in a lab and I will not do so without liablity insurance.
    Do what you want, but know that legal liablity is also something that should be thought about.
    What risks you take in your own kitchen are up to you, no one will stop you, but we sure like to provide what we know is safety tested, as well.

  • digdirt2
    13 years ago
    last modified: 9 years ago

    Since we are soap boxes I'll just add that my goal is different from yours. Mine is to get people to the point where they follow the current guidelines to start with because then they would be "mostly safe" at least. If they then want to move beyond that to testing their own products for additional safety, fine. That is their choice.

    But since the vast majority of home canners aren't even aware that any guidelines exist much less follow them, or have any grasp of the concepts of pH much less density I will continue to focus on that instead.

    If one believes even 1/2 of what gets posted on food preservation forums then learning how to use a pH meter is the least of their problems. You'd be amazed at what folks who claim to be experienced home canners will do much less what the ones who admit to being inexperienced will do. Making up their own low acid recipes and sticking it in a jar and make up a processing time is common practice. And "I have been doing it that way for years and I'm still alive" is their justification.

    Just a few comments I have run into in the past 3 days on 2 other forums:

    Fats and thickeners? No problem. Sure you can can butter and milk because Jackie says you can. You can mix the types of meats as long as you process for the longest one's time. BWB hot dogs? No problem. BWB green beans and corn? No problem if you add aspirin. Add acid to anything? Why? Good heavens, no! Use a pressure canner? Not on your life! I've been canning for 30 years but never heard of the BBB. What is it? My gauge (which was 30 years old and never tested) says 10 lbs so everything is safe. If the instructions say BWB for 30 mins. then pressure canning for 10 is plenty. I pressure canned them for 2 hours but the weight never jiggled so are they safe? When you can your lasagna do you use cottage cheese or ricotta?

    Sorry but with that level of food preservation ignorance out there can you imagine what it would be like if you turned some of these folks lose with a pH meter?

    Dave

  • foothillfarm
    13 years ago
    last modified: 9 years ago

    Professional people are expected to have a certain level of competence in their particular discipline or field of expertise. Its also expected that they will professionally and accurately perform their services, according to the common standards of conduct of their profession. For whatever reason, intended or unintended, if a professional person fails on the job, they can be held responsible for any harm they cause to another person or business. This is when you need liability insurance.

    I do not provide advice for a fee. Therefore, I do not need to carry liability insurance for stating an opinion. So far, no one from the garden web has sent me any money for advising them to think for themselves.

    I appreciate your concern, but I stand by what I said, not testing, even when using an "approved recipe" is more dangerous.

    For those of you interested in pH meters, Google: Cornell University Purchasing pH meters.

    Many local colleges have classes on food safety and canning.

    Worried that something you canned isn't safe?

    Beverly Ellen Schoonmaker Alfeld (known as Jamlady) will test a jar for you.

    I'm in the kitchen making zuke bread & butter pickles, from one of her recipes. Am I going to test it? Darn tootin.

  • tracydr
    13 years ago
    last modified: 9 years ago

    I have to believe that safety tested recipes carry a huge margin of safety to make up for the fact that the lowest common denominator is a 5th grade educated person witH an IQ of 70 and no training in food preservation.
    How else could volume measured recipes, which have a huge chance for measurement error be deemed safe? If it was that critical to accurately measure ingredients perfectly, they would only give weight measured recipes.
    The amount of error that occurs in measuring a dry flour or water by volume is enormous by baking standards. I can only imagine the Amount of error in measuring multiple cups of a chopped tomato or pepper!

  • Linda_Lou
    13 years ago
    last modified: 9 years ago

    If you think liability insurance is only for paid people, then why do our volunteers have to have insurance ?
    I spend a lot of my time as a volunteer. I only get paid for certain jobs I do. I have to have liability insurance for both situations.

    I liked how Carol described how acidification takes place in her example on the other thread. Great job, Carol !
    She is correct in what she said.

  • digdirt2
    13 years ago
    last modified: 9 years ago

    I believe it's time we took hokus pokus out of canning and put the science in.

    I agree completely which is why I am pleased to have all of the scientific input available from NCHFP/USDA because without it we would ALL just be guessing and the rate of home canned food illness would be much higher than it is.

    The history of home food canning publications at NCHFP are an enlightening read. ;)

    Dave

  • tracydr
    13 years ago
    last modified: 9 years ago

    I found a great historical read in the free section for IPAD books. It's a post WW1 book on canning. Very fascinating and kind of funny!

  • pattypan
    13 years ago
    last modified: 9 years ago

    this thread is very interesting ! I too have been in medical research for 25 years and believe the usda guidelines must be supersafe to account for the lowest common denominators in I.Q. and also water pH variations. but i think i am buying a really good pH meter and a pressure canner for tomato products- because the government would like to do all our thinking for us, and i just won't let them!
    on the other hand, i'd like to know the history of deaths from home canned foods. were people dropping like flies in the 18th century? or before 1950 ? saying "i've canned this way for 30 years and i'm still here" may be an excuse-and it's also an observation.
    this is a slippery slope, but what exactly is the chance of getting botulism poisoning from a splash in the eye, and is it dose dependant? considering the greater chances of dying from an auto accident or smoking, it sounds a bit like a scare tactic. wouldn't cargill and monsanto love to have everyone stop canning and buy their "safe" foods? you know, the ones with all those recalls?

  • digdirt2
    13 years ago
    last modified: 9 years ago

    but i think i am buying a really good pH meter and a pressure canner for tomato products- because the government would like to do all our thinking for us, and i just won't let them!

    Your choice of course but if "tomato products" is the only thing you are canning then the risk and $$$ hardly seems worth it. Guidelines are easy for them. No pH meter needed.

    on the other hand, i'd like to know the history of deaths from home canned foods. were people dropping like flies in the 18th century? or before 1950 ? saying "i've canned this way for 30 years and i'm still here" may be an excuse-and it's also an observation.

    I think it is pretty clear from all the information above and in the other discussions here of this issue that not only was vinegar much stronger than it is today and that after-opening hard boiling of the foods was done to kill the toxin but that statistics weren't kept that far back. ;)

    Still, since you are in medical research, then you likely have access to even more online publications and current research on the issues associated with botulism than most of us do. For most, the USDA and CDC stats are sufficient but that is a good place for you to start your research that will help you make an informed decision. Canning is a science after all.

    Dave

  • flutterbyca
    13 years ago
    last modified: 9 years ago

    Odd to come across this discussion today. I was just wondering out loud to my husband this morning if I could get a pH meter and test food as I canned it. I did not know that pH changes over time as the food is stored.

    On thing that bothers me, though, is the insistence that the USDA and Ball are the only correct sources of canning information. I have a hard time believing that nowhere else in the world can be trusted with canning instructions. It seems a bit like American arrogance to have that attitude.

  • Linda_Lou
    13 years ago
    last modified: 9 years ago

    As far as I know, no other places do the testing as was done here, it takes between $10,000 and $50,000 per recipe to test them.
    Now, someplace like the Williams Sononma cookbooks as and example, are not going to test those recipes in books for that kind of money.
    It isn't American arrogance, that I can see, it is a matter of time and money spent on testing.

  • macybaby
    13 years ago
    last modified: 9 years ago

    It is the "lowest common denominator" thing and the fact that people don't want to be responsible for their own lack of good judgment.

    Why does a plastic bag need a warning that it could cause suffocation?

    Why does my bottle of water have a warning that the cap is small enough a child could choke on it?

    Was does the sun shield that goes in the windshield of my car say "REMOVE BEFORE DRIVING CAR"


    But what I really wanted to say - I followed the link Lindalou posted way back (july 09) at the start of this thread (before I realized how old it was) and got myself signed up for the online class.

    I thought they had stopped offering that class because of lack of funding, so I was sure glad to see it available.

    Cathy

  • digdirt2
    13 years ago
    last modified: 9 years ago

    On thing that bothers me, though, is the insistence that theUSDA and Ball are the only correct sources of canning information

    Not really, ;) there is also Bernardin in Canada (homecanning.com), freshpreserving.com, several land grant university extension websites, and several other canning books we have discussed here in the past. Mrs. Wages.com also posts tested recipes using their products.

    While it is true that much of their recipes are based on the USDA testing that comes out of the University of Georgia, as Linda Lou said, why would they want to spend the time and the money duplicating all the research just for some 'national' label? Unless of course they found the research to be invalid. Apparently they haven't. ;)

    Dave

  • calliope
    13 years ago
    last modified: 9 years ago

    Research is being done all the time concerning testing for pathogens in processed food and I read about a month ago of a new lower-cost, fast response botulism test being developed. It would benefit the food industry and distribution channels primarily, but I can see with the rapid and cheap DNA tests and anti-body tests where food safety tests could be within reach of many sources in the not-to-distant future.

  • bunnyman
    12 years ago
    last modified: 9 years ago

    I just thought this thread interesting. With economic problems around the world looking very sticky I'm betting more and more people start to can.

    Looks like I'm buying a pressure canner and some litmus paper. I like to play so litmus paper seems to be the cheapest way to test my recipe.

    What I've read here has made me more comfortable with what I'm canning. Btw... I studied some philosophy and advise never to be 100% certain of anything. Smart people make dumb mistakes every day... we are human.

  • John__ShowMe__USA
    12 years ago
    last modified: 9 years ago

    > Looks like I'm buying a pressure canner and some litmus paper. I like to play so litmus paper seems to be the cheapest way to test my recipe.

    And the least reliable. (litmus paper) Am all for the pressure canner though.

  • digdirt2
    12 years ago
    last modified: 9 years ago

    I studied some philosophy and advise never to be 100% certain of anything. Smart people make dumb mistakes every day... we are human.

    Very true. But while cooking is an art and as such, other arts such as philosophy can play a role, canning is a science. There is ample instruction and evidence available to anyone interested that mistakes are easily prevented - especially hazardous ones.

    Using litmus paper to test your recipes is one of those potentially hazardous mistakes. So is "playing" with canning recipes. Please don't make your gifted friends pay the price for your need to "play" at canning.

    Dave

  • Linda_Lou
    12 years ago
    last modified: 9 years ago

    Good advice, John and Dave !!! I so agree.

  • macybaby
    12 years ago
    last modified: 9 years ago

    Before you go with the litimus paper test, you need to research shelf stability of acids. Just because it tests OK before you put it into the jar, does not mean it's going to stay that way with your own made up recipies.

    What you also need to do is periodically take some out and re-test, and for safety sake, retest when you open to make sure the PH level stayed low enough. With PC, you kill the mircoroganizm, with low PH, you simply keep it from getting active, and if for some reason the PH level rises, it will get active and produce spores.

    I have found it's simple enough to can up basic sauces, and then customize them after opening. There are lot of very good tested recipies out there for most condements and there are enough safe ways to modify (like changing dry seasonings) to have a variety.

  • hcoon
    12 years ago
    last modified: 9 years ago

    I've read this thread before, and now again and the new posts.

    I have to admit I'm confused. While some folks have seemed to advocate for Ph testing recipes they make up, there are some who say they want to test the Ph of their foods to make extra sure they are safe... just in case the water or the fruit or the whatever threw the Ph out of whack.

    And other people are saying that only tested recipes are certain of safety -- and you shouldn't test because it's not accurate.

    But then, I'm thinking that if I used tested recipes, and got in the habit of testing them with a calibrated instrument, both before canning and after, that I would build up a little database of what the Ph of my food was. Then, if my tested recipe DID have something happen to it, I would be more likely to know if it really WEREN'T safe, right?

    I guess I don't understand not having more information rather than less....

  • hcoon
    12 years ago
    last modified: 9 years ago

    Okay, have been doing more background reading and starting to understand the issue around the consistency of the pH measurement. The information you're getting may so off (to a larger degree than I would have thought), and thus my premise of "more information" may be inaccurate if that's true. And perhaps you'd then be misinformed about the pH of your food...

  • digdirt2
    12 years ago
    last modified: 9 years ago

    Not only mislead by your pH starting readings but there is also the pH stability issue Macy mentioned. The approved recipes have been repeatedly tested over time for pH stability and bacterial growth - 2 mos., 4-6 months, 9 mos. etc. That is one reason why multiple samples must be submitted when a recipe is submitted for testing.

    So we would have to test and retest and then test again our own recipes upon opening the jar.

    And their testing is done with highly calibrated instruments, not litmus paper which most of us learned in high school chemistry class can be easily affected by just the humidity in the air or the oil on your skin. That professional equipment is not normally available to the home canner without spending umpteen $$$$ and even then requires frequent recalibration to be accurate.

    Possible? Maybe. Practical? No.

    Dave

  • NearlyNomads
    11 years ago
    last modified: 9 years ago

    Suppose you could vacuum-pack a meat (probably chicken or turkey) with a highly-acidic marinade. If it were stored at room temperature for 24 or 48 hours, what would be the likelihood of it being safe to eat?
    If the meat was raw when packed?
    If the meat was thoroughly cooked when packed?

    Many thanks!

    Edit: Sorry, I should have posted this on the main forum and can't figure out how to delete this post.

  • readinglady
    11 years ago
    last modified: 9 years ago

    I don't know the likelihood but I do know that meat is very dense, so odds are the center of the meat is not acidified at all.

    Add to that the leaching of meat juices (high pH) into the acidic marinade, thus reducing the acidity of the solution.

    A lot can change in 24-48 hours.

    Carol

  • texasjohn
    11 years ago
    last modified: 9 years ago

    Because of the "new" regulations on added acid to
    tomatoes, I only water bath pickle beets, pickles
    and fruit products.

    I got away from canning for about ten years and
    boy what a differance that made. The tomatoes and
    every thing they were added to had such an acidic
    taste. In a word, they were awful tasting

    Not having my own testing lab, the only safe water
    bath method for me is I don't can tomato products

  • digdirt2
    11 years ago
    last modified: 9 years ago

    Use citric acid instead of the bottled lemon juice. It doesn't change the flavor in any way.

    Dave

    PS: the acidification "rules" aren't new. They went into effect in the 70's.

  • texasjohn
    11 years ago
    last modified: 9 years ago

    I used the citric acid but that gave
    the tomatoes an acidic taste. Used in
    soups and chillies, that acidic taste was
    very noticeable. Therefore no tomato canning
    for me.
    I don't think lemon flavored tomatoes would
    be any better.
    I would not care to can contrary to the
    guidelines, even though the guidelines cause
    the tomatoes to taste bad.

    PSS: Dave, that is why I put the -new- in "" .
    john

  • Refused
    10 years ago
    last modified: 9 years ago

    Stumbled onto your forum and this thread while researching on pickling fish that do not need to be refrigerated. I have an older book that references useing 15% acetic acid vinegar instead of the modern 5% to pickle the fish (also states the fish would have to be soaked in water for a day or two before eating). Since fish reach equalibrium readily, especially in smaller bite sized pieces and 10% acetic acid vinegar is listed at a PH of 2.4 (5% listed as 3.6) would making up a batch of 10% or 15% acetic acid vinegar and useing that satisfy the lower PH need thus eliminating the need to refrigerate. Food grade 99.85% acetic acid is available at Amozon and since distilled vinegar is just acetic acid and water mixed making up a proper solution would be easy.

  • readinglady
    10 years ago
    last modified: 9 years ago

    I don't know that any of us are in a position to draw conclusions regarding the relative safety of that recipe, but I find myself wondering about the texture of pickled fish held at room temp in an acid solution that strong.

    Carol

  • digdirt2
    10 years ago
    last modified: 9 years ago

    Agree with Carol that the safety of that approach is impossible to determine except perhaps by a trained food scientist. Safety aside, not only the texture but the appearance and most importantly, the taste, of the end product would be questionable in my opinion.

    Is your primary goal making pickled fish or having fish that can be stored without refrigeration? Are smoking and/or canning options acceptable? Current instructions are available for both.

    Dave

  • readinglady
    10 years ago
    last modified: 9 years ago

    I think also that we often forget that "not refrigerated" does not necessarily mean room temp for some of these older recipes. A lot of people kept perishables in root cellars or stillrooms where the temperature even on hotter days would be considerably lower than ambient. People also were very cognizant of storage limits and a lot of foods would be consumed speedily, not kept for long periods.

    For really long-term storage I'd guess fish would be salted, smoked and/or dried.

    Carol

  • kriswrite
    10 years ago
    last modified: 9 years ago

    I don't have time to read the whole thread, so I apologize if someone else has mentioned this - but you may wish to read Putting Up by Stephen Palmer Dowdney. He sells canned foods in a boutique business and teaches the government recommended methods, which are quite different from home canning methods. They involve reading the pH of canned food.

  • digdirt2
    10 years ago
    last modified: 9 years ago

    you may wish to read Putting Up by Stephen Palmer Dowdney

    We have reviewed this publication here before. Read it sure. Use it for guidelines for home food preservation? Please don't. Its interpretation and application of commercial FDA guidelines has little, if any, relevance to safe home canning. For example, the errors resulting from using litmus paper for pH testing, as he recommends, is well documented.

    Dave

  • Linda_Lou
    10 years ago
    last modified: 9 years ago

    Smoking and pickling won't make the food safe for room temp. storage.
    Smoking is only a flavor agent. It won't preserve anything.

    I don't see why you don't just use our current recipe and method for pickling fish. It turns out fine.

  • Refused
    10 years ago
    last modified: 9 years ago

    Hot smoking still requires refrigeration after, cold smoking/jerky can be done, canning is a no brainer, most salting instructions say refrigerate after, have done and am doing refrigeration after required pickling. What I was after was a historicly authentic food safe way of preserving fish by pickling that did not require the refrigeration of the jars. The purpose of this is my own edification/increasing my knowledge base/historic cooking research/alternatives in storage. Do my current methods work and are safe? Yes. Looking to expand them, The question I ask is could, THEORECTICALLY, this process using the increased acetic acid vinegar meet the criteria to keep the PH of the entire batch below the 4.2 PH level. Yes I aknowledge there may be a change of texture and the flavor may take on a more vinegar taste, but I have norske ancestory (think lutefisk, but I dont want to go in that direction). What brought me to post was I did notice some scientific types posting toward the beginning of the thread and was hoping they might answer. I know I will not get a definative yes answer as there is no .gov approval stamp but I would like opinions.

  • Refused
    10 years ago
    last modified: 9 years ago

    Should have posted this sooner but here is a reply I got back from an inquiry -
    Thank you for your interest in the National Center for Home Food Preservation. Regarding your question:

    (My sent message) Background, I am a home food preservationist with an extensive history of home sausage making (both with hot ((refrigeration required)) and some cold smoking ((humidity and temperature controlled to produce country cured sausage, no refrigeration required)), home canning (pressure canning only, I do not trust water bath under any circumstances) and extensive dehydrating experience. I have done a little pickling under the recommendations that the USDA has out in regards to fish and hardboiled eggs (including the need for refrigeration). However in my research into historic preservation techniques I have found references to pickling (especially) fish preserved at room temperature. The references also stated that the vinegar solution used at the time was homemade and was of strength higher then the present 5% available for modern commercial sales. Given that botulism spores growth is inhibited at a PH of 4.6 and they can not therefore produce the toxins, the fact that! a 10% or 15% acetic acid can be readily produced using food safe glacial acetic acid (99.85% available commercially mixed in proper ratio with water (yes, acid to water, I remember basic chemistry) and the PH of the 10% solution is approximately 2.4 and given that 1.5â x 1.5â x 0.75â pieces of fish would readily equalize PH is this theoretically a safe preservation method. Please do not give me the standard rely of not recommended or approved due to lack of experimental data etc. brush off, I am just looking for a theoretical answer.

    (The reply) This is Elizabeth Andress, Director of the National Center. I personally apologize for not getting back to you sooner, but we have been trying to keep up with people needing help with more standardized recommendations and methods of preserving.

    I can tell you that under the circumstances you describe with the low pH environments, that theoretically botulism spore germination and toxin production does not seem likely. But that is indeed as much as I can say. You would want to make sure the fish pieces get below pH 4.6 throughout fairly quickly to keep it longer at room temperature (probably at least within 24 hours). It is not a brushoff but a fact that no one here has any practical experience with pickling fish at room temperature (or for that matter, at any temperature). We do not have USDA pickling or smoking for fish on our website or in the USDA canning guide, but there is information from Oregon State University we have shared on smoking fish.

    I have pretty much relied on contacts in Alaska, or formerly in Oregon, for issues related to smoking and pickling of fish.

    You also might find an actual food microbiologist actively researching with bacteria at Univ. of Wisconsin who knows more in detail of C. bot. patterns.

    Thank you,
    Elizabeth Andress

  • northeast_chileman
    9 years ago
    last modified: 9 years ago

    I'm bumping this thread for one reason, what model pH meter do you own?

  • digdirt2
    9 years ago
    last modified: 9 years ago

    Oakton 10. Comes with a full set of buffering test liquids.

    Dave

  • seysonn
    9 years ago
    last modified: 9 years ago

    I am thinking about purchasing a half decent pH meter with calibration feature. An accuracy of as low as 0.1 on pH scale is good enough for all intent and purposes, for me.

    On the pH testing and canning on small scale one does not need an elaborate research lab. FDA would certify a kitchen with a reliable pH meter. I know a member at GW (in Hot Peppers forum) that recently was certified to make/bottle hot sauce and market. I am sure there must be certain qualification for the kitchen equipments other than just a pH meter but the thrust is on processing time and acidification in BWB method.

    I read most of the posts and comments; Some objected pH testing, arguing that the water that goes into it can be alkaline. Well that might be true. If your city water is alkaline ( pH of 7 and higher) just don't use it instead use bottled water. But as far as I know most municipal waters across USA have a pH in 5 to 6 pH range. That is actually low acid.

    On the leaching effect and diluting acidity, if the canned items are acidic to begin with (as most fruits and vegetables are) The effect of leaching water cannot be that high to throw the pH into unsafe territory if it is originally @ 4 or lower. pH does not change linearly. It would take a lot of water to increase pH by just 0.10. let me give you and example.

    If you have a solution with 50/50 w/v(distilled water and 5% acidity vinegar) it will have a pH of under 2.60. Now if you dilute it to 75/25 w/v the pH will be about 2.70.

    So the dilution argument is a weak one. UNLESS the canned material is HIGHLY alkaline. In that case use lab tested recipe, to be safe.

    Seysonn

  • 2ajsmama
    9 years ago
    last modified: 9 years ago

    Yes there a local health dept requirements for commercial kitchens (separate handwashing sinks, etc.) but if you recall he not only had to purchase and use (keep records of each batch) a reliable pH meter (0.02 +/- IIRC, perferably with temperature compensation) but also take the BPCS, register as an FDA facility, and get each and every recipe reviewed by a process control authority and tested by a food safety lab.

  • seysonn
    9 years ago
    last modified: 9 years ago

    OK AJSM,

    I was trying to say that it is perfectly fine to use a RELIABLE pH meter. And I already said about other FDA compliance. So then you don't need a laboratory to check and research for existence/growth of spores etc.

    Today's consumers are more educated and they have a technology behind them to do things and decide for themselves in the 21st century. SURE , consumers needed more governmental help and guidance in mid 1900, to lead them every step of the way. But today at the dawn of the 21st century we can do a lot of things on our own, including what we should eat, how we should cook and how we should eat.

    Everything said, it is up to everyone of us to do what we think is the right thing to do. So if someone wants to follow strictly some agency's guideline with out a question, he/she is free to do so. And that is what forums like this is all about, to debate the prose and cons.

    Seysonn