Survey of Home Canning Practices and Safety Issues in the U.S.

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Survey ofHome Canning Practices and Safety
Issues in the U.S.

• E. M. DSa1, E. L. Andress1, J. A. Harrison1 and
  M. A. Harrison2.
• Department of Foods Nutrition Extension,
• (2) Department of Food Science Technology,
• The University of Georgia, Athens, GA 30602-4356
  Paper 005-04
• Presented at the Institute of Food Technologists
  Annual Meeting,
• Chicago, IL, July 29, 2007

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ABSTRACT The use of science-based, tested
processes is critical to the safety of
home-canned foods. A national survey was
conducted to determine consumer knowledge and
practice of home canning techniques. Results
indicate a critical need for education and
increased awareness of safety-related concerns.
The objective was to identify food safety
concerns in the practice of home canning, and to
compare these results with those from a previous
survey (year 2001). A 2005 national telephone
survey of U.S. adults was conducted, using a
42-item questionnaire about consumers home
canning knowledge and habits. 801 complete
interviews were obtained from randomly selected
households across the nation, with a 95
confidence level and a 30 cooperation rate.
Survey results indicate that about one in five
households canned foods in 2004. The most popular
sources of instructions continue to be family or
friends (51.2, earlier 48) and cookbooks
(16.7, earlier 19). 30.5 altered recommended
canning procedures. Most commonly canned foods
were vegetables (64.9, earlier 71) and tomato
products (59.2, earlier 60). 9.2 used
non-nutritive sweeteners in jams or jellies,
with sucralose being most popular. The risky
practice of open-kettle canning (hot fills only)
is still practiced for fruits and tomatoes (44
of canners), vegetables (35.4) and meats or
seafood (20). 32 (earlier 38) of all canners
had jars that did not seal properly, and 35.6
(earlier 37) stored their home-canned foods for
longer than 12 months. Education about and
reinforcement of science-based food preservation
resources are essential in promoting safe
home-canning techniques. Failure to use
recommendations can result in foodborne illness
including botulism, or food spoilage. These
survey results identify current critical areas of
concern in U.S. consumer canning practices, and
therefore provide guidelines for continued
Extension-based efforts in this area.
INTRODUCTION Home food preservation methods
continue to be key interest areas for consumers
wanting to use the abundance from their home
gardens or local markets to have homemade
specialties all year. Preserving this food safely
while maximizing food quality are essential
features of Extension food preservation
recommendations. Home canning continues to be a
popular means of preserving food at home
(Andress, 2002). The importance of safe home
canning practices must be emphasized. Using
unsafe practices could lead to occurrence of
foodborne illness (including the potentially
fatal botulism), or at the very least food
spoilage. This national telephone survey
conducted in 2005 was aimed at determining
consumers home canning and home food
preservation knowledge and practices, and
identifying potential areas of food safety
concern. Results obtained from this survey will
also be compared with the results of a similar
2001 national telephone survey. Areas of
similarity or divergence between the two surveys
will be documented.

• OBJECTIVES
• To conduct a randomly-based national survey of
  U.S. households practicing home food preservation
  techniques on a routine basis
• To determine consumer knowledge of safe home
  canning techniques.
• To identify types and quantities of foods being
  canned at home.
• To identify potential unsafe home canning
  practices that need to be targeted by Extension
  communicators.

METHODS A questionnaire was developed by
researchers at the National Center for Home Food
Preservation and the Survey Research Center,
University of Georgia, that was translated into a
91- item (42 closed- or open-ended item canning
survey) instrument. Respondents could choose more
than one appropriate response for some questions.
Between April 4 and June 16, 2005, a national
telephone survey of adults was conducted.
Telephone interviewers received training and
practice in areas of survey purpose, methods,
standard telephone interviewing procedures and
were supervised at all times to ensure quality
control. A total of 8,848 numbers were called
and 2, 676 eligible interviewees were contacted.
This yielded 801 complete interviews, of which
174 respondents canned foods at home. It is the
data from this group of 174 respondents that is
being analyzed in this presentation. In order
to reduce bias in response and draw accurate
inferences from the adult population, sampling
procedures utilized ensured that all households
had near-equal selection chances for inclusion in
the sample. A 95 confidence interval and a
sampling error of /- 5 insured that estimates
produced were precise and accurate. A 30
cooperation rate was obtained, and one-fifth to
one-quarter of all interviews were monitored.
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• What are their sources of information?
• Family or friends (51), generic cookbooks
  (17), directions from pressure cooker
  manufacturer (13), Ball Blue Book (7.5),
  directions from canning jar/lid manufacturers
  (7), magazines or newspapers (4), Extension
  Service (3), the Internet (3), community
  cannery instructions (0.5) and other (13).
  In comparison, the 2001 survey results showed
  that the top information categories were also
  friends or relatives (49) and generic cookbooks
  (19), followed by directions from canning
  jar/lid manufacturers (10), directions from
  pressure cooker manufacturers (9), USDA
  publications (3), Extension Service (2) and
  other (25).
• 55 of respondents (earlier 67) used their
  canning instructions as is, while 30.5
  (earlier 29) adapted the instructions for their
  personal use.

• What are they canning and how?
• 65 canned vegetables (71 earlier), 59 canned
  tomatoes/tomato products (60 earlier), 52
  canned fruit (47 earlier) and 65 canned pickled
  products. Of those canning pickles, 20 used
  firming treatments, with salt water soak (22),
  pickling lime (13), ice water soak (13), and
  Pickle Crisp (9) being the most popular firming
  treatments.
• Non-nutritive sweeteners were used by some home
  canners in jams/jellies/preserves (9.2), fruits
  (6.32), and pickles/relishes/salsas (1.15).
  Within this group, Splenda (sucralose) was the
  most popular (used by 42), followed by Sweetn
  Low (21), Equal (5) Sweet One (5).
• Figure 5 represents the canning methods used by
  respondents who canned fruits and tomatoes,
  vegetables and meats/poultry/seafood. Table 1
  represents a breakdown of the types and
  quantities of food items canned by respondents.

Table 1 Amounts of various food canned at home Table 1 Amounts of various food canned at home Table 1 Amounts of various food canned at home Table 1 Amounts of various food canned at home Table 1 Amounts of various food canned at home
Number of respondents (n174) who canned quantities of Number of respondents (n174) who canned quantities of Number of respondents (n174) who canned quantities of Number of respondents (n174) who canned quantities of
1-10 pints 11-50 pints 51-100 pints gt 100 pints
Fruits 10 41 11 8
Fruit products (sauce, juice purée, syrup) 8 15 5 1
Tomatoes 3 53 14 6
Tomato Sauce or Juice 5 24 6 2
Other vegetables 10 37 14 7
Soup mixtures 4 6 - -
Cucumber pickles 4 21 3 1
Other pickled vegetables 6 11 - 2
Relishes/Chutneys 4 6 1 -
Salsas 6 20 2 -
Pickled fruits - 3 - -
Jams/Jellies/Preserves 16 37 10 2
Barbecue Sauce 3 - - -
Flavored vinegars 1 1 - -
Meat and Poultry 2 4 3 1
Fish and seafood 3 6 1 -
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• EQUIPMENT USE AND MANAGEMENT
• Only 12 of respondents had the dial gauge on
  their pressure canner tested in 2004. 11 have a
  pressure canner without a dial gauge. Of those
  who had the dial gauge tested, 12.5 (2) had it
  tested at the Extension Service, 25 (4) at a
  hardware store and 6.25 (1) at a utility
  company. (Note Extension agents often test
  pressure canner dial gauges at hardware stores.)
• 16 of respondents reported making altitude
  adjustments when using their pressure canners,
  while 10 reported making altitude adjustments
  when using a boiling water canner.
• 49 of respondents used an electric range for
  home canning, 24 used a gas range, 15.5 used an
  electric smooth-top range and 1 used sealed gas
  burners.

• JARS AND LIDS
• Approximately 64 of respondents (earlier 74)
  used home canning jars with 2-piece lids, 10
  used home canning jars with other lids, 2.3 used
  recycled jars from commercially canned foods, 7
  used the older home canning jars with rubber
  rings, 7.5 respondents used metal cans.
• 32 of respondents reported having jars that did
  not seal properly after canning. For the jars
  that did not seal, 20 reprocessed them, 37.5
  refrigerated and consumed them quickly, about 4
  froze the contents of the jars for later
  consumption, and 43 discarded the contents.

• FOOD USE, STORAGE AND SPOILAGE
• 11.5 of respondents reported serving the home
  canned food as is, with no heating, 30 brought
  the food to a boil before serving, 21 boiled the
  food for 10 minutes or more, 24 warmed the food
  on a stovetop, oven or microwave, 19 used the
  canned food as an ingredient in other recipes, 7
  steamed the food, and 3 used other means of
  preparation.
• How long do they store the canned food? 18
  reported using the home canned food within 6
  months, 42.5 stored the food for 6-12 months,
  and 36 reported storing the food for more than 1
  year.
• What are the signs that canned food (home canned
  or commercially-canned) is spoiled? 86
  recognized a bulging lid as a sign of spoilage,
  84 mentioned mold, 83 mentioned off-odor,
  78 mentioned off-color, 76 mentioned
  leakage, 56 mentioned spurting liquid when
  container is opened and 44 mentioned floating
  fruit or vegetables as a sign of spoilage.
• Only 45 of respondents thought that home canned
  foods could be spoiled without obvious signs of
  spoilage, and 12 reported that their home canned
  food from the 2004 canning season had spoiled.

• SUMMARY AND CONCLUSIONS
• There is similarity between the results of the
  2001 and 2005 surveys in some areas, but not all.
  The lack of consistent use of science-based home
  canning techniques and equipment among home
  canners continues to be a disturbing observation.
• Family and friends continue to be the largest
  category source of instructions for home canning
  recommendations. Greater use of USDA and
  Extension sources for recommendations would be a
  highly desirable shift in this observation.
  Mobilizing County Extension and community
  efforts in this area, coupled with greater
  publicity given to existing USDA
  recommendations, is a way to change this trend.
• Also disturbing is the continued use of unsafe
  home canning methods like oven canning,
  open-kettle canning, and the use of boiling
  water canning for low-acid foods. Again,
  education and information dissemination in this
  area should be emphasized.

REFERENCES 1. Andress et al., 2002. Current Home
Canning Practices in the U.S. Institute of Food
Technologists Annual Meeting Presentation, Paper
46B-3. 2. Bason, J. 2006. Materials and Methods
Statement. Survey Research Center, The University
of Georgia, Athens, GA. 3. Bason, J. 2001.
Materials and Methods Statement. Survey Research
Center, The University of Georgia, Athens, GA
This project was partially funded through a grant
from the National Integrated food Safety
Initiative (Grant No. 00-51110-9762) of the
Cooperative State Research, Education, and
Extension Service, U.S. Department of
Agriculture.