Fall brings the end of the garden season and the beginning of apple-everything season. And curiously, a lot of mention of apples everywhere on the internet. Including click-bait articles, because if you don’t click you might die.
After seeing a few on new guidelines for canning apples, I decided to take a look.
It was noted that the Ball Blue Book, 38th Edition, included several new recommendations for safely canning apples. And as they shared the information so clearly, I see no need to re-write or summarize:
A study conducted by the Ball® Home Canning Test Kitchen showed that some modern apple varieties along with growing conditions and techniques can produce apples that are less acidic than originally thought. Historically, apples were considered safe for water bath canning without added acid since they were below the safe pH of 4.6. Apples with a pH above 4.6 potentially can create a more hospitable environment for harmful bacteria, like Clostridium botulinum. Further, apples, like many fruits, generally decrease in acidity during storage. Adding lemon juice to canning recipes ensures that the pH of the canned product remains below 4.6, which is the critical threshold for inhibiting the growth of C. botulinum. Per a Ball® statement, “the quantity of lemon juice added to each (recipe) was based on experiment of different types of apple recipes using the highest pH apple species that was identified, and pH modeling to understand the margin of different pH and temperature thresholds while keeping existing processing time recommendations the same.”
Out of an abundance of caution, Ball® has added bottled lemon juice to all apple-based recipes where the apple was expected to be the lowest pH ingredient in the recipe and incorporated that guidance into all Ball® home canning 2024 recipe publications. Ball® does not currently recommend that consumers discard any apple products they have canned previously as prior publications are still within USDA recommendations. Rather the company is advising consumers using Ball® recipes in publications beginning 2024 to follow the acidification guidelines.
It is a best practice for home canners to always use the most current version of a recipe publication and to follow tested recipes as researched and written by reputable recipe sources like the USDA, NCHFP, cooperative extension services, and Ball®. All researched recipes will include updated guidelines for that recipe at the time of publication.
Ball® acknowledges that the National Center for Home Food Preservation (NCHFP) and USDA have not updated their guidance on apple acidification and that the company is unaware of any documented safety issues arising from current apple recipes.[1]
The National Center for Home Food Preservation has not changed their recipes or recommendations and assures that there’s no risk as long as proper canning guidelines are followed. However, they do emphasize the following:
In addition to following proper canning guidelines, we advise always using fresh apples for canning. Ensure that the apples are free from any signs of decay or mold. Fresh apples in their natural state are generally more acidic, contributing to the overall safety of the canning process. It is important to note that older apples may naturally have a lower acidity level. As an alternative to canning and storing at room temperature, individuals are encouraged to refrigerate or freeze products made with apples if there is a question of their pH.[2]
A USDA Cooperative Extension site noted the importance of canning only freshly picked apples, and indicated that the increase in the pH levels noted by the Ball group may stem from the variety of apple (Fuji, in this case) and/or the fact that they were purchased from a store, and thus not “freshly” picked.[3]
So there you go. Updated canning guidelines for processing apples include the addition of commercial lemon juice. I wasn’t aware that acid levels varied among the varieties of apples, though it stood to reason. Of course, the more tart varieties would be more acidic. And it didn’t occur to me that apples become less acidic the longer they are stored, though that stands to reason also. Conversely, it never occurred to me that more acidic apple varieties would have a longer storage life. I should probably plant more of those. Besides, I like tart apples.
You could also do a mix of apples to keep ph down low, the addition of crab apples would help.
ReplyDeleteExile1981
Would vit c powder be useful as lemon juice seems hard to put into long term storage?
ReplyDeleteI don't think I've seen any research about using vitamin C powder in canning. I would go with citric acid instead. 1 tablespoon of lemon juice equals 1/4 teaspoon of citric acid. And citric acid is shelf stable.
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