Food Protection Trends - September/October 2019 - 383

TABLE 4. Pearson's product moment correlations between correctly presented
information and other select factors in weblog salsa recipes

Total guidelines
correctly presented

Total guidelines
incompletely
or incorrectly
presented

Total guidelines
not included

Facebook followers

Acid ratio

Pearson's
Correlation

-0.08

-0.61

-0.082

0.038

Significance

0.56

0.00

0.55

0.78

strongly negatively correlated with "not included" scores
(Table 4). This trend was observed both within and across all
categories, meaning that where correct information was not
given, it was much more likely to be omitted than incorrect.
Anecdotally, much of the information scored as "incorrect"
either was incomplete or represented outdated guidance from
validated sources.
Of the blogs evaluated for this study, the number of
Facebook followers ranged from 719 to 3,256,656, with an
average of 145,953 (Table 1). No statistically significant
relationships between this metric and any other factor were
discerned. Adjustments for home canning at high altitude
were provided by only eight (14%) blogs. Although more
than half of recipes (34, or nearly 61%) correctly specified
the length of time to process jars in a boiling water bath, only
ten (29%) of these indicated that processing time should
start after a rolling boil is achieved, representing a critical risk
of under-processing. Additionally, only four (7%) of the 56
recipes reviewed provided correct information on all three of
the following measures: total processing time, when to start
processing time and altitude adjustment.
Eighteen food blogs (32%) either mentioned or provided a
hyperlink to outside guidance. When provided, these sources
were most often USDA webpages, but they also included
Cooperative Extension, Ball® and NCHFP references. Food
blogs that provided hyperlinks to such a reference were
significantly more likely to have higher total "correct" scores.
Of the 56 home canned salsa recipes screened, 24 (43%)
failed to use standard volumes. Only eight (14%) specified
the correct type and strength of acid(s) to ensure safety
(Table 5) and only five recipes (9%) actually contained
sufficient quantities of acid for the volume of vegetables
used (Fig. 2, Table 5). Noncompliant recipes lacked up to
16 T of necessary bottled lemon juice to achieve the safety
benchmark. According to the Choice Salsa standard, recipes
should contain a minimum of 2.33 T bottled lemon juice (or
4.66 T vinegar at 5% acidity) per combined cup of peppers
and onions (represented as a target acidification ratio of
2.33:1) (2). The mean acidification ratio across all recipes
in this study was 0.94 T per cup of peppers and onions, less

than half the level recommended to ensure safety during
extended anaerobic storage. Analysis of acidification volume
to tomato volume revealed that 12 (21%) of the 56 recipes
failed to meet even the minimum USDA acidification
guidelines for tomato volume alone. No relationship was
observed between acidification ratio and overall adherence
to USDA guidelines (Table 4), meaning that even in cases
where guidance for home canners was largely complete and
accurate, recipes would not ensure that the resulting salsa was
properly acidified.
DISCUSSION
Traditionally, salsas are mixtures of low-acid foods, such
as onions and peppers, with acid foods, such as tomatoes.
Depending on ingredient ratios, the natural acidity of salsa
mixtures may not be high enough to be safely processed
in a BWB, which is still the most common method for
canning in American homes (1). According to research
conducted by the NCHFP and USDA Guidelines, the
use of validated salsa recipes and acidification with
commercially bottled lemon juice or with vinegars with
5% acidity is required to ensure safety for home canned
salsas (2, 24, 32). Utilizing nonstandard units (e.g., 1
green pepper), draining tomatoes and/or employing
unspecified acidulant type can alter the acid balance,
yielding an unsafe product for processing in a BWB and
thus increasing the risk of foodborne illness, particularly
in instances of insufficient heat processing.
Processing times, including instructions regarding when
timing should begin, were correctly presented in only 10
(18%) of the recipes analyzed. The combination of heat
treatment and low pH is necessary for control of Clostridium botulinum in canned foods. Spore germination and
toxin production during storage are primarily inhibited
by control of pH to a level below 4.5 (14). None of the
recipes evaluated specified that pH had been tested, which
makes adherence to acidification guidelines even more
vital. When the findings for thermal processing and acidification are taken together, they indicate a real risk for the
production of unsafe food and foodborne illness.

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Food Protection Trends - September/October 2019

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