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Microbial growth in many foods can be controlled by proper refrigeration. Thus, it is recommended that refrigerators be maintained at 40 o F (4.4°C) or below. However, no recent extensive studies have been reported that assess actual temperatures at which cold foods are stored over time within the home. The objective of this project was to evaluate the temperatures of refrigerators in 200 homes in the United States. Loggers were used to record temperatures each minute in several locations in each refrigerator. In some homes, a thermocouple was also placed in a commercially sealed hot dog and in a cup of yogurt. Data were analyzed using Excel and SPSS-PC. Mean temperatures were 35.5, 38.0 and 41.3ºF (1.9, 3.3 and 5.2°C) for the top shelf, bottom shelf and door, respectively, with 9, 25 and 61% of these areas having average temperatures above 40ºF (4.4°C). Over 66% of refrigerator door temperatures were above 40ºF (4.4°C) for more than eight hours per day. The temperature of the foods fluctuated less than the temperature of the surrounding air. Temperatures rose above the danger zone (above 40ºF or 4.4°C) for more than 2 hours a day for 33%, 45%, and 80% (top shelf, middle shelf, door, respectively) of refrigerators. Consumers need to check the temperature regularly and should be advised to store temperature-sensitive foods on the top shelf of the refrigerator when appropriate.
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Food Protection Trends, Vol. 27, No. 3, Pages 168–173
2007, International Association for Food Protection
6200 Aurora Ave., Suite 200W, Des Moines, IA 50322-2864
*Author for correspondence: 615.963.5619; Fax: 615.963.5033
A peer-reviewed article
A Comprehensive Evaluation
of Temperatures within
Home Refrigerators
Institute of Agricultural and Environmental Research, Tennessee State University, Nashville, TN 37209, USA;
Department of Family and Consumer Sciences, Tennessee State University, Nashville, TN 37209, USA; and
Sensory Analysis
Center, Department of Human Nutrition, Kansas State University, Manhattan, KS 66506, USA
Microbial growth in many foods can be controlled by proper refrigeration. Thus, it is recommended
that refrigerators be maintained at 40
F (4.4°C) or below. However, no recent extensive studies have
been reported that assess actual temperatures at which cold foods are stored over time within the
home. The objective of this project was to evaluate the temperatures of refrigerators in 200 homes
in the United States. Loggers were used to record temperatures each minute in several locations in
each refrigerator. In some homes, a thermocouple was also placed in a commercially sealed hot dog
and in a cup of yogurt. Data were analyzed using Excel and SPSS-PC. Mean temperatures were 35.5,
38.0 and 41.3ºF (1.9, 3.3 and 5.2°C) for the top shelf, bottom shelf and door, respectively, with 9, 25
and 61% of these areas having average temperatures above 40ºF (4.4°C). Over 66% of refrigerator
door temperatures were above 40ºF (4.4°C) for more than eight hours per day. The temperature of
the foods fluctuated less than the temperature of the surrounding air. Temperatures rose above the
danger zone (above 40ºF or 4.4°C) for more than 2 hours a day for 33%, 45%, and 80% (top shelf,
middle shelf, door, respectively) of refrigerators. Consumers need to check the temperature regularly
and should be advised to store temperature-sensitive foods on the top shelf of the refrigerator when
Data indicate that 25% of reported
foodborne illnesses are traced back to
food items that are consumed in the home
(13). However, little information is avail-
able to determine if any of these cases
are actually attributable to the domestic
environment and if, or to what extent, do-
mestic food handling practices contribute
to the problem. Although most outbreaks
are attributed to poor temperature control
of raw and cooked foods, many are asso-
ciated with cross contamination (14).
Regulatory agencies have also recog-
nized the importance of safe consumer
food-handling practices. A refrigerator is
recognized as one of the most important
pieces of equipment in the kitchen for
helping keep food safe. It helps maintain
the microbiological safety of the food
supply by inhibiting the growth of bacte-
ria that reproduce rapidly at temperatures
above 40°F (4.4°C). Consumers are told
to store their cold foods at 40°F (4.4°C)
or below (3, 5). However, some bacteria
such as Listeria monocytogenes, will continue
to thrive at cold temperatures and have
the potential to grow in the refrigerator
and subsequently cause serious illness and
possibly death. A recently released risk as-
sessment on Listeria in ready-to-eat foods
(6) noted that both refrigerator storage
temperature and duration of refrigerated
storage before consumption are impor-
tant factors in measuring the possible
public health impact to consumers from
foodborne listeriosis. The few studies that
have reported on cold storage of food in
homes have concluded that lack of ad-
equate practices for determining the tem-
perature of the refrigerator in the home
is a major problem (2, 4, 9). For example,
rather than using a thermometer, most
consumers rely on how cold the food
feels (8). Only 25% of consumers in one
study in the United States reported having
a thermometer in their refrigerator, and
most persons were unaware of the ideal
refrigerator temperature (12). In a study
conducted in Greece in which household
refrigerator temperature was assessed,
Sergelidis et al. (11) reported that 55% of
refrigerators had temperatures of 48°F
(8.9°C) or higher. Similarly, in a study of
elderly Britons, 70% had refrigerators that
were too warm for the safe storage of
food (10). In the most thorough study of
refrigerator temperatures, which was con-
ducted in the United Kingdom, James and
Evans (9) found that fewer than 2% of
refrigerators operated below 41
F (5.0°C)
at all times and that a third were consis-
tently over 41
F (5.0°C) Around 70% of
the refrigerators monitored were above
F (5.0°C) more than 50% of the time.
Data from a more recent study in New
Zealand show that 30% of refrigerators
were operating above 41°F (5.0°C) (7).
In spite of the need for compre-
hensive information on storage of cold
foods in the home environment, few
recent studies have been reported. No
studies have been found that investigated
actual temperatures at which cold foods
are stored within homes in the United
FIGURE 1. Distribution of mean temperatures for three locations in home refrigerators; N = 98, 187, and 197
for top shelf, bottom shelf, and door, respectively
States, variations of temperature within
different areas of the refrigerators, and
whether consumers are aware of cold
storage recommendations.
The objective of this project was to
evaluate the consistency and appropriate-
ness of temperatures for different loca-
tions within domestic refrigerators over
time. Temperature differences among
refrigerator areas and selected foods were
also assessed.
Temperatures from household re-
frigerators in routine use were collected
during visits to participants’ homes for
in-person interviews. The purpose of
the interview was to assess consumers’
knowledge and practices on handling and
storing refrigerated foods at home. Tem-
perature loggers (Precision Temperature
Data Logger, Spectrum 1000, accuracy +
0.1°F (0.05°C), were placed in 200 refrig-
erators in homes in Tennessee, Kansas,
and Florida. Generally, three loggers were
used, one placed on the bottom shelf of
the door panel, and the others in one or
more of four other locations, such as top
shelf, middle shelf, meat drawer, vegetable
bin, the site of each depending on the
model of the refrigerator. Items stored in
the refrigerators were kept in their origi-
nal arrangements. This report describes
results obtained from loggers placed on
the door panel and from those placed at
the back of the top and bottom shelves.
In some refrigerators, a thermocouple
also was placed in a commercially sealed
hot dog (111 refrigerators) or a cup of
yogurt (89 refrigerators), both of which
were provided by the researchers. These
foods, which are commonly found in re-
frigerators, represent solid and semi-solid
“ready-to-eat” foods of interest to food
safety researchers. Each logger recorded
the temperature every minute for at least
three consecutive days.
Temperature data were downloaded
for each refrigerator and evaluated by use
of Excel and SPSS-PC. Analysis included
calculations of means and standard
deviations for temperatures measured
by loggers placed on top and bottom
shelves and doors; minimum, maximum,
and range of temperatures, and frequency
distributions of numbers of refrigerators
and amount of time per day that those
refrigerators exceeded 40°F (4.4°C).
Although most scientists report
temperatures in Celsius, the tempera-
ture data in this paper are present-
ed not only in °C
for the scientific
community but also in °F, because
the Fahrenheit scale is familiar to Ameri-
can consumers and because refrigerator
temperature recommendations made in
such programs as FightBAC
are speci-
ed in °F.
FIGURE 2. Percentage of refrigerator compartments that exceeded 40°F (4.4°C) for specified lengths of time; N = 98, 187,
and 197 for top shelf, bottom shelf, and door, respectively
Figure 1 shows the distribution of
mean temperatures recorded in three
locations within home refrigerators. The
mean temperature was at or below the
currently recommended 40°F (4.4°C ) in
91% of the top shelves but in only 79% of
bottom shelves and 45% of refrigerator
doors. None of the mean temperatures
of the top shelves within each refrigera-
tor exceeded 45°F (7.2°C), the maximum
temperature that may have been recom-
mended when some of the refrigerators
in the study were manufactured, whereas
3.7 and 12.7 percent of bottom shelves
and doors, respectively, exceeded 45°F
(7.C). Overall temperatures (mean
± standard deviation) for top shelves,
bottom shelves, and doors were 35.5
± 3.96, 38.0 ± 3.98 and 41.3 ± 3.85°F
(1.9 ± 2.2, 3.3 ± 2.2 and 5.2 ± 2.1°C),
respectively. Nearly half of the top-shelf
areas, 46.9%, had mean temperatures of
35°F (1.7°C) or less, while 22.9% of bot-
tom shelves and only 4.6% of refrigerator
doors averaged 35°F (1.7°C) or less. Thus,
as expected, because the cold air enters
in the area close to the top shelf in most
refrigerators, this area was the coldest for
most of the refrigerators. Temperatures
fluctuated as much as 2F (14.C)
within an area during the study. The
mean temperature fluctuation for
the top shelves was 10.1 ± 4.1°F
(5.6 ± 2.3°C), a range that was sig-
nificantly greater than the range for
the bottom shelves and refrigerator doors,
(6.7 ± 1.98 and 7.0 ± 2.81°F, or 3.7 ± 1.1
and 3.9 ± 1.6°C, respectively), again prob-
ably because this is where the cold air en-
ters the unit. However, it should be noted
that because the temperature uctuates
greatly, the time at which the consumer
checks the temperature could be critical
in determining whether the food is being
kept cold enough or not, and whether
adjustments to the temperature or repairs
to the refrigerator are warranted.
The length of time each refrigerator
compartment exceeded 40°F (4.4°C) is
displayed in Fig. 2. The air around the top
shelf was the coldest for almost all refrig-
erators. The temperature never exceeded
40°F (4.4°C) for 40% of them, in contrast
to 33.7% of bottom shelves and only
9% of the doors. Thus, the consistently
high temperature of the door is a major
concern. When the temperature of the air
exceeded 40°F (4.4°C), it was for shorter
periods each day, from 1–20 min up to 2–4
h, for the top shelves than for the other
areas. Only 2.4% of top shelves continu-
ously exceeded 40
F (4.4°C). In contrast,
FIGURE 3. Distribution of mean temperatures for hot dogs and yogurt in home refrigerators; N = 111, and 89 for hot dogs
and yogurt, respectively
a greater proportion of refrigerator
doors exceeded 40°F (4.4°C) in each of
the longer intervals, beginning with the
4–8 h period. Over one third (39.3%)
of doors and 11.1% of bottom shelves
were continuously above recommended
refrigerator temperature.
Since the temperature of the food,
not of the air, is probably the most impor-
tant factor in temperature control, we also
recorded temperature in thermocouples
placed in hot dogs and yogurt cups.
Lower mean temperatures were recorded
in a greater percentage of commercially
sealed hotdogs than of yogurt containers,
as shown in Fig. 3. The mean temperature
was 36.F (2.C) for hot dogs and
37.1°F (2.8°C) for the yogurt. The hot
dog averaged 0.2°F (0.1°C) colder, and the
yogurt 0.7°F (0.4°C) colder, than the sur-
rounding air. Therefore, the hot dogs and
yogurt had mean temperatures slightly less
than those recorded from temperature
sensors placed in the same refrigerator in
the same area, indicating that these foods
maintained the low temperature better.
Air temperature within a refrigerator
would be expected to change rapidly as
the door is opened, foods are added or
taken out, cold or warm air enters, or the
defrost cycle occurs.
Only 18 of the 200 refrigerators
evaluated in this study (9%) contained a
refrigerator thermometer when we arrived
in the home. Of additional concern was
the fact that for those homes where a ther-
mometer was present in the refrigerator,
the respondents reported that they rarely
or never checked it.
Thus, circumstances do appear to
exist in many homes that could lead to
increased microbial growth in refriger-
ated foods, and consequently lead to a
higher risk of consumers contracting a
foodborne illness. A large percentage
of refrigerators in the current study
were not maintaining the recommended
temperature of 40°F (4.4°C) or below
continuously. The top shelf had the lowest
mean temperature, probably because the
cold air inlet is located in this area in most
refrigerators. The door was too warm in
the majority of refrigerators and stayed
that way a large percentage of the time;
indeed, nearly 40% of refrigerator doors
were above 40
F (4.4°C) all of the time.
Thus, foods that are potentially hazard-
ous, such as milk and eggs, should not be
stored on the door, which is of concern
because many refrigerators have compart-
ments on the door especially designed for
storage of these foods. Consumers should
be educated to place highly perishable
foods in the main compartment of the
refrigerator and use the refrigerator door
only for items that do not spoil readily,
such as condiments (mustard, ketchup,
etc.), highly salted foods such as pickles
or olives, and cold beverages.
All refrigerators should be equipped
with a thermometer that should be
checked regularly, which is not the cur-
rent situation, since few consumers have
refrigerator thermometers (only 9% in
the current study). This gure of 9%
is much lower than gures reported by
other researchers, who asked consumers
if they had a thermometer in their refrig-
erator (1). There is a clear need to inform
consumers of the value of refrigerator
thermometers and to encourage their
correct use.
An additional problem arises in
that refrigerator thermometers are of
little value if not properly used. When
asked, 33% of consumers with refrigera-
tor thermometers replied that they had
not checked them within the last week
(8). We recommend that the refrigerator
thermometer be checked frequently, be-
cause the large uctuation in refrigerator
temperatures reported herein suggests
that infrequent checks would not reliably
indicate overall temperature maintenance.
Observing the temperature initially in
the morning would provide insight into
the ability of the refrigerator to main-
tain proper temperature. Checking the
thermometer temperature at different
times during the day following periods
of normal use would give consumers in-
formation regarding if and how often the
temperature in their refrigerator exceeds
40°F (4.4°C). We further recommend that
the thermometer be placed on the door,
since this is nearly always the warmest part
of a domestic refrigerator and thus would
provide the best indication as to whether
the entire refrigerator is cold enough.
In our previous study, a signicant
proportion (45%) of consumers reported
that they had changed the temperature
setting within their refrigerator in the
past six months, suggesting an aware-
ness of the need to maintain an adequate
temperature (8). The decision to change
the temperature setting, however, usu-
ally was based on intuition; consumers
judged refrigerator temperature most
commonly by assessing the temperature
of cold beverages. Clearly, these methods
are unreliable. Such decisions should be
based on observations from a refrigerator
Consumers need to realize the im-
portance of maintaining cold foods at the
recommended temperature in the home
to reduce the risk of foodborne illness.
Moreover, it is imperative that consum-
ers recognize that the responsibility for
controlling food temperature in the home
rests on them. Regulatory agencies such
as the Food and Drug Administration, US
Department of Agriculture, and health
departments can not help guarantee the
safety of foods once these have been
purchased. Consumers need to adhere to
agency recommendations for handling
and storing foods to best avoid food-
borne illness. Researchers and educators
need to provide instruction to consum-
ers to ensure that they are aware of and
understand current recommendations.
Furthermore, we believe that it would be
helpful if manufacturers were required to
install thermometers in all refrigerators
and include instructions for their proper
use, as well as information on the safe
storage of refrigerated foods.
This material is based on work
supported by Food and Drug Admin-
istration under cooperative agreement
FD-U-001950, and US Department of
Agriculture under Project TENX-0402-
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This study developed and evaluated risk communication messages for ready to eat (RTE) foods targeted towards consumer storage practices in a food safety health campaign. Concepts were determined from a fractional factorial design of five categories of attributes potentially present in health promotion: title, message, graphic, slogan, and icon. Consumers viewed a subset of concepts and scored how useful the concept was in remembering to throw away RTE foods that were stored too long. Regression analysis determined which combinations of message attributes were most likely to result in using the information to throw out foods, which could help prevent foodborne illness. Findings showed that for this type of information, a graphic is a critical element for the printed schematic. The slogan (i.e., a short statement similar to a jingle or tag-line in a commercial) may be important to consumers, but the icon was not important.
... Other studies indicate food-borne diseases can be caused by inappropriate food storage. For example, the lack of periodic refrigerator cleaning and management may promote the risk of food-borne diseases (16,17). Fungal agents from various sources including dirty hands, un- (18). ...
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Background: Food-borne pathogens are one of the most important problems in less developed and developed countries. Commercial refrigerators are a potential source of fungal contamination that causes food spoilage, food-borne intestinal infectious diseases or mycotoxin diseases. Objectives: The purpose of this study was to determine the distribution of psychotropic fungi in food storage refrigerators (n = 50) with temperatures above and below 0ºC at selected restaurants (n = 25) located in the city of Ahvaz, Iran. Methods: Samples were collected from the surfaces of the refrigerators by using sterile swab sticks pre-moistened with sterile distilled water, and then each collected sample was plated out on Sabouraud dextrose agar medium. Finally, all fungi were counted and identified based on macroscopic and microscopic characteristics. Results: According to our results, 100% of the sample refrigerators showed fungal contamination. Cladosporium sp. (42.34%) and Mucor sp. (0.06%) had the highest and the lowest frequency of fungi recovered from our research, respectively. Furthermore, the P value calculated indicated a significant correlation between refrigerators above 0ºC and refrigerators below 0ºC (P < 0.00001). Conclusions: The presence of fungi in commercial refrigerators could be an indicator of a potential source of food spoilage and food-borne diseases. Therefore increased education, and proper packaging and refrigerator management are recommended since regular cleaning of these refrigerators is important in order to prevent food-borne diseases and other health risks.
... The raw milk samples were stored for 72 hr at two different refrigeration temperatures considering that, a review of 23 survey studies conduced in Italy from 1991 to 2016 (Ricci et al., 2018) temperature of domestic refrigerators highly variable. Several Authors (Godwin, Chen, Chambers, Coppings, & Chambers, 2007;Reale et al., 2013) pointed that domestic refrigerators often reach temperatures of or 7°C or higher, rather far from 4°C, recommended for a safe storage. ...
The sale of raw milk from vending machines is allowed in several European Countries. Since unpasteurized milk could harbor foodborne pathogens, the boiling treatment is highly recommended before consumption. In this study, the effect of storage temperatures, generally recorded in domestic refrigerators, as well as the effect of domestic boiling and industrial microwaving on the microbiological, and nutritional quality of raw bovine milk from vending machines was evaluated. Results highlighted that some microbial groups increased during the storage at 8°C. Noticeable, Listeria spp., even if initially present in low amounts, reached levels that would be a cause of concerns. Based on these results, the effects of domestic boiling and microwaving on the survival of L. innocua intentionally added was evaluated, as well as the nutritional features of treated milk. Both treatments were able to eliminate L. innocua, but only microwaving preserved the nutritional quality of milk. This study presents the application of microwaving as an alternative treatment to enhance the quality of raw bovine milk. Domestic storage conditions (especially refrigeration temperatures and time) produce a strong decay in the microbiological quality of the product and Listeria levels might become a real concern. In addition, boiling treatment, imposed by law prior to milk consumption, produces a further depletion of the nutritional quality, producing a strong decay in thermolabile compounds. A suitable solution for heat treatment of raw milk from vending machines could be represented by microwaving at 780 W for 1.35 min. This datum could serve for setting a specific program in domestic microwave ovens for sanitization of raw milk in home environments.
Queso fresco (QF), a fresh soft cheese, is one of the most popular Hispanic cheeses in the United States and is frequently associated with Listeria monocytogenes outbreaks. Listeria monocytogenes can grow and thrive at room temperature as well as refrigeration temperatures. A combination of antimicrobial agents provides a larger spectrum of listeriostatic and listeriocidal activity resulting in a more effective approach toward the control of L. monocytogenes. In this study, we evaluated the efficacy of 3 Food and Drug Administration-approved generally recognized as safe (GRAS) antimicrobials, nisin (NIS), lauric arginate ethyl ester (LAE), and ε-polylysine (EPL), and the endolysin PlyP100 individually and in combination for control of L. monocytogenes in QF at 4°C, 7°C, and 10°C. Additionally, growth curves of L. monocytogenes were obtained in BHI broth and QF at these temperatures. In order for an antimicrobial to be considered a postlethality treatment for L. monocytogenes, it should not allow an increase of more than 2-log over the product's shelf life. Three treatments, PlyP100, PlyP100 + NIS, and EPL + LAE, effectively kept the pathogen below the 2 log growth threshold at 4°C. However, at 7°C and 10°C, none of the antimicrobial treatments could inhibit L. monocytogenes growth (i.e., <2 log). Overall, our results suggest the importance of considering the effect of cold storage temperatures above 4°C on the antilisterial efficacy of antimicrobial treatments in QF.
Blueberries have increased in popularity in recent years due to their nutritional benefits and sensory characteristics. However, to preserve quality and extend shelf-life, they need to be maintained at refrigerated temperatures and high relative humidity, conditions that are not routinely met along the supply chain. Poor temperature management leads to quality deterioration, increasing waste/losses along the supply chain. This study examined the impact of each step along the supply chain on the physichochemical quality and shelf-life of blueberries, identifying the most critical steps from field to consumption. The following steps were identified as critical in the blueberry supply chain: shipping to distribution centre (DC) (72 h at 5 °C), store display (48 h at 15 °C), and consumer (48 h at 20 °C). Given the economic importance of weight loss and its link to fruit quality and shelf-life, a boosted regression tree (BRT) model was built to predict weight loss using the post-harvest environmental conditions of a simulated supply chain applying different temperature-time scenarios. The model explained 84 % of the variance on the test set and highlighted the interactions of supply chain conditions on weight loss.
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To assess the food storage knowledge and practice of elderly people living at home. Three phase survey data collection: face to face interviews; dietary diaries with a food frequency questionnaire; and follow up interviews. Urban Nottingham. 809 elderly people (aged 65+) randomly selected from general practitioner lists. Respondent's refrigerator temperature; knowledge of freezer star rating; understanding of "use by" and "sell by" dates; reported ability to read food product safety labels. From a weighted total of 645 refrigerators measured, 451 (70%) were too warm for the safe storage of food (> or = 6 degrees Celsius). Only 41% of respondents (n = 279) knew the star rating of their freezer. Within a smaller sub-sample knowledge of the "use by" and "sell by" dates was good, but 45% of these respondents reported difficulty reading food labels. The storage of foods at inappropriate temperatures was not independent of socioeconomic or demographic status, and tended to be more likely among the poorer and those not living alone. Food storage practices among the majority of elderly people interviewed in this study do not meet recommended safety standards to minimise the risk of food poisoning.
Proper cooling of foods is known to reduce spoilage and help prevent food-borne illnesses. Nonetheless, little is known about consumers' awareness of guidelines regarding appropriate refrigeration of food or their actual refrigeration practices. Focus groups of consumers of common ethnic backgrounds were designed to evaluate food safety knowledge and home refrigeration practices. Differences were found among ethnic and age groups regarding knowledge of proper refrigeration practices and general food safety, as well as common refrigeration practices. Most participants did not know proper refrigerator temperatures, and none used refrigerator thermometers. The most common sources of food safety information were relatives and extension educators. Eight focus groups of common ethnicity were conducted involving a total of 53 persons. Ethnic groupings included Hispanic, African American, and Caucasian. Comparisons of responses from the eight groups provided insights into consumer practices by ethnic group, whereas the opinions of minority individuals might be overshadowed in focus groups of mixed ethnicity. Although misconceptions were apparent, participants offered many suggestions for avoiding food-borne illnesses (Table 1). They were less certain when the questions focused on refrigeration and cooling practices. Few participants knew the correct refrigerator temperature, and none had a refrigerator thermometer. Most judged the refrigerator temperature from everyday experience (e.g., "I feel the milk to see if it is cold"). It was commonly thought that the dial setting needed to be changed in the summer for food to stay cold.
There has been extensive media coverage of the Pacific Northwest outbreak of foodborne illness caused by Escherichia coli O157:H7 in 1993 and continuing smaller incidences of both E. coli and salmonella transmission by food. An increase in consumer awareness and knowledge of microbial food safety was expected as a result. A telephone survey of Oregon food preparers (using a random-digit-dialing household sample) in December 1995 and January 1996 revealed that knowledge about foodborne illness was greater than in previous studies. Of the 100 respondents, 88% named appropriate foods as being at high risk for food poisoning. Salmonella contamination was recognized as a problem in food by 99%, E. coli by 100%, but campylobacter by only 7%. Major foods which have been associated with salmonella were named correctly by 90% and with E. coli by 87%. Although raw or rare meats or fish were rarely eaten or ordered by respondents, hamburgers were frequently requested to be cooked to "medium" doneness. Many said they would thoroughly cook food contaminated with bacteria to make it safe to eat (56% for salmonella and 59% for E. coli) but 40% responded that the foods either couldn't be made safe to eat or that they didn't know of a way. Respondents in general could not identify specific groups of people especially at risk for foodborne illness. Educational efforts should focus on risk groups and ways that consumers can prevent foodborne illness.
Use of safe food handling practices in the home could reduce the number of foodborne illnesses. The objective of this project was to obtain baseline data on the safe food handling knowledge and practices of consumers to aid in the development of effective educational programmes. A food handling questionnaire was developed and completed by 426 Nebraskan respondents. Knowledge and practice questions were based on the most important contributory factors in reported foodborne illness outbreaks. Knowledge scores (correct responses) ranged from 2 to 29 with a mean of 20 ± 4. When compared with the knowledge score, the respondents' education level, where they lived and their sex were statistically significant. Almost all (96%) of the respondents stated that they practised safe food handling when persons were infected. Approximately half of the respondents indicated that they practised safe food handling when handling contaminated raw foods and using foods from unsafe sources. About 45% of the respondents inappropriately left foods at room temperature. One-third of the survey respondents improperly held hot foods. Cross-contamination was a concept understood by 75% of the respondents. Results indicate that food safety education should be targeted on specific groups who are less knowledgeable about safe food handling practices. Results also indicate that a number of respondents knew proper food handling concepts but did not put those concepts into practice. Therefore, increasing the adoption of safe food handling practices by consumers should become an important aspect for educators in food safety educational programmes.
Chilled foods are stored for periods of between a few hours and many days in domestic refrigerators. However, there are little published data on the temperature performance of domestic refrigerators within the home. A survey has been taken in 252 households in the UK and some of the results are presented in this paper. The refrigerators investigated in the survey were found to have an overall mean temperature of approximately 6°C, which ranged from 11.4 to −0.9°C. Temperature ranges over the whole refrigerator varied from 4.5 to 30.5°C with 3.7% of the total being warmer than 20°C. On average 29.9% of refrigerators operated below 5°C and 66.7% operated below 7°C. Few refrigerators (7.3%) ran, on average, above 9°C. No refrigerator characteristic (apart from type) could be related to temperatures or temperature distribution in the refrigerators investigated.RésuméLes aliments réfrigérés sont entreposés dans les réfrigérateurs domestiques, pour des périodes allant de quelques heures à plusieurs jours. Cependant, peu de données ont été publiées sur la performance des réfrigérateurs domestiques en matière de température, au domicile des consommateurs. Une enquête a été effectuée auprès de 252 ménages au Royaume Uni, et on présente quelques résultats dans cet article. Les réfrigérateurs considérés dans l'enquête avaient une température globale moyenne d'approximativement 6 deg C (elle variait de 11,4 à −0,9 deg C). Les plages de température globale allaient de 4,5 à 30,5 deg C, mais pour 3,7% des réfrigérateurs, la température était supérieure à 20 deg C. En moyenne, 29,9% des réfrigérateurs fonctionnaient à une température inférieure à 5 deg C, et 66,7% à une température inférieure à 7 deg C. Peu de réfrigérateurs (7,3%) fonctionnaient à une température supérieure à 9 deg C. Aucune caractéristique des réfrigérateurs, mis à part leur type, ne pouvait avoir une incidence sur les températures ou sur la distribution de température, dans les réfrigérateurs étudies.
Epidemiological data from Europe, North America, Australia, and New Zealand indicate that a substantial proportion of foodborne disease is attributable to improper food preparation practices in consumers' homes. International concern about consumer food safety has prompted considerable research to evaluate domestic food-handling practices. The majority of consumer food safety studies in the last decade have been conducted in the United Kingdom and Northern Ireland (48%) and in the United States (42%). Surveys (questionnaires and interviews), the most frequent means of data collection, were used in 75% of the reviewed studies. Focus groups and observational studies have also been used. One consumer food safety study examined the relationship between pathogenic microbial contamination from raw chicken and observed food-handling behaviors, and the results of this study indicated extensive Campylobacter cross-contamination during food preparation sessions. Limited information about consumers' attitudes and intentions with regard to safe food-handling behaviors has been obtained, although a substantial amount of information about consumer knowledge and self-reported practices is available. Observation studies suggest that substantial numbers of consumers frequently implement unsafe food-handling practices. Knowledge, attitudes, intentions, and self-reported practices did not correspond to observed behaviors, suggesting that observational studies provide a more realistic indication of the food hygiene actions actually used in domestic food preparation. An improvement in consumer food-handling behavior is likely to reduce the risk and incidence of foodborne disease. The need for the development and implementation of food safety education strategies to improve specific food safety behaviors is reviewed in this paper.
Government agencies have recently emphasized the importance of food safety. Reducing the risk of foodborne illnesses within the home requires American consumers to put government refrigeration and freezer recommendations into practice; however, little research has been conducted regarding the use of proper refrigeration and freezer storage practices by consumers. A random sample survey was conducted to examine attitudes and practices of proper refrigeration and storage techniques of consumers in Peoria County, Illinois, and to determine whether gender, age, education, and income level have an effect on these variables. Eighty-one of 500 random sample surveys mailed were returned between 10 January and 15 February 2005. The majority of the participants were female (56, 69.1%), were 50 to 59 years old (18, 22.2%), had a bachelor's degree (33, 40.7%), and had a reported total household income of 60,000 dollars or greater (39, 91.4%). Average attitudinal scores indicated that participants thought it was important to take proper steps to prevent foodborne illnesses in the home; however, 68.8% of participants scored poorly on the practice portion of the survey. Only 12.3% of participants stated that they had a thermometer in their freezer, and 24.7% had one in their refrigerator. Eighty-four percent of respondents did not store eggs correctly in the refrigerator. No significant relationships (P < 0.05) were found within this sample population. These results suggest that further evaluation of consumer practices and attitudes is needed to better understand consumers so that they can be effectively educated about the prevention of foodborne illnesses at home.
Center for Food Safety and Applied Nutrition Foodborne illness: What consumers need to know
  • Drug Food
  • Administration
Food and Drug Administration. Center for Food Safety and Applied Nutrition. 2001. Foodborne illness: What consumers need to know. Available at http://www.foodsafety. gov/~dms/fsefborn.html. Accessed November 1, 2006.
Center for Food Safety and Applied Nutrition Food Safety Inspection Service Centers for Disease Control Quantitative assessment of relative risk to public health from foodborne Listeria monocytogenes among selected categories of ready-to-eat foods
  • Drug Food
  • Administration
Food and Drug Administration. Center for Food Safety and Applied Nutrition. Food Safety Inspection Service. Centers for Disease Control. 2003. Quantitative assessment of relative risk to public health from foodborne Listeria monocytogenes among selected categories of ready-to-eat foods. Available at lmr2-toc.html. Accessed November 1, 2006.
ADA) and ConAgra Foods Foundation Home food safety refrigeration survey Available at:
  • American Dietetic Association
American Dietetic Association (ADA) and ConAgra Foods Foundation. 2001. Home food safety refrigeration survey. Available at: pages/media/releases/apr6_2001_ key.jsp. Accessed November 1, 2006.