Consumer implementation of recommended food safety practices, specifically relating to time and temperature control of ready-to-eat (RTE) food products associated with listeriosis are crucial. This is particularly the case for at-risk consumers such as older adults, given the increased listeriosis incidence reported internationally among adults aged ≥60 years. However, data detailing older adults' cognitive risk factors associated with listeriosis are lacking. Combining data about knowledge, self-reported practices, and attitudes can achieve a cumulative multilayered in-depth understanding of consumer food safety behavior and cognition. This study aims to ascertain older adults' cognition and behavior in relation to domestic food handling and storage practices that may increase the risks associated with L. monocytogenes. Older adults (≥60 years) (n = 100) participated in an interview and questionnaire to determine knowledge, self-reported practices, and attitudes toward recommended practices. Although the majority (79%) had positive attitudes toward refrigeration, 84% were unaware of recommended temperatures (5°C) and 65% self-reported “never” checking their refrigerator temperature. Although most (72%) knew that “use-by” dates indicate food safety and 62% reported “always” taking note, neutral attitudes were held, with 67% believing it was safe to eat food beyond use-by dates and 57% reporting doing so. Attitudes toward consuming foods within the recommended 2 days of opening were neutral, with 55% aware of recommendations and <84% reporting that they consume RTE foods beyond recommendations. Although knowledgeable of some key practices, older adults self-reported potentially unsafe practices when storing RTE foods at home, which may increase risks associated with L. monocytogenes. This study has determined that older adults' food safety cognition may affect their behaviors; understanding consumer food safety cognition is essential for developing targeted food safety education.

Data from the United Kingdom indicate that listeriosis incidence has dramatically increased in recent years (27); the majority of cases are reported to be associated with older adults (30, 42) and not associated with pregnancy (28). Given the increased incidence of illness associated with Listeria monocytogenes among older adult consumers in the United Kingdom, research on the food handling, storage, and consumption practices of older adult consumers has been recommended to determine contributory factors associated with listeriosis in the domestic kitchen (2). There is a need to establish how food is stored and handled by this consumer group and also the reasons for this.

The role of the consumer as being “the final line of defense” for ensuring the safety for food products in the domestic setting is widely recognized (36, 46, 50). Consequently, there are specific consumer food safety recommendations for controlling the risks associated with L. monocytogenes in the home kitchen: (i) following “use-by” dates on unopened prepacked ready-to-eat (RTE) food products, (ii) consuming RTE food products within 2 days of opening, and (iii) ensuring the safe operating temperatures of domestic refrigerators (≤5°C) (15). Implementation of such practices relating to time and temperature control of RTE food products associated with L. monocytogenes may reduce the risks associated with listeriosis; such practices are of particular importance to older adults because the risk of listeriosis increases with increasing age (43). Food products typically associated with listeriosis are those able to support L. monocytogenes growth (20) and are often RTE products (32) with extended refrigerated shelf life (33). Such foods include RTE meat products (26, 40, 56), RTE smoked fish products (23, 24, 26), dairy products (4, 38), and soft cheeses (7, 9).

Behavioral data show that older adults fail to adhere to recommendations, which results in inadequate storage of RTE food (18). However, there is a need to combine such data with social cognitions, including knowledge, attitudes, and self-reported practices, to provide a more in-depth understanding of older adults' domestic food safety practices and to find out why such behaviors are implemented; cumulatively, this data can be used to inform the development of risk communication (18). A review that assessed the inclusion of the key risk factors associated with listeriosis in consumer food safety studies established the need for attitudinal data, in conjunction with knowledge and self-reported practices, particularly of older adult consumers. Combining such cognitive and behavioral findings will give more insight into why food safety practices are implemented (17).

Self-reported data have been widely used in consumer food safety research (74 to 96% of consumer food safety studies undertaken from 1977 to 2013 have included self-reported practices data) (17, 46) and are beneficial for insight into consumer behavior when it is not possible to determine actual behavior through observation. Although widely used, the limitations of self-reported data are recognized (8); self-reported practice data may be subject to social desirability bias (31), because respondents may overreport “good” food safety practices or underreport “bad” behaviors (16) in attempting to give what they perceive to be the correct response and to portray a positive image (46, 48).

Consumer knowledge of food safety is one of the most commonly researched components of consumer food safety research (44 to 75% of studies undertaken 1977 to 2013 include assessment of consumer knowledge) (17, 46). Data on the association between knowledge and behavior suggest that no significant relationships exist between knowledge and actual behavior (14, 19, 41, 61). However, determination of knowledge and self-reported practice data does give an insight as to whether consumers are aware of food safety practices.

Attitudes can be considered to be determinants of behavior because they are reported to predispose people to certain behaviors (29). Consumer attitudes, particularly toward food safety, are understood to influence behavior (47); and they give insight into why some food safety practices are implemented and some are not. Attitudinal data have been less frequently included in consumer food safety studies than knowledge and self-reported practice data. Indeed, data regarding older adults' attitudes toward risk factors associated with listeriosis in the domestic kitchen are particularly lacking (17).

Combining data about knowledge, self-reported practices, and attitudes can achieve a cumulative multilayered in-depth understanding of consumer food safety behaviors and cognition. Such findings can inform the development of targeted food safety educational initiatives.

Consequently, the aim of this study is to ascertain older adult consumers' knowledge, self-reported practices, and attitudes toward domestic food handling and storage practices that may increase the risks associated with L. monocytogenes.

Older adult consumers were recruited (using online advertising and posters on community notice boards), and 100 consented to participate in the study. Predetermined recruitment criteria included being aged ≥60 years, living independently and not in residential care homes, coming from South Wales, UK, and reporting being responsible for preparing and storing raw and RTE food products at home. Supermarket vouchers worth £10 were offered to participants as an incentive for participation in the study. A review of background literature and United Kingdom consumer food safety recommendations informed the development of questions for a questionnaire and interview. Ethical approval was granted from the Cardiff School of Health Sciences (Cardiff Metropolitan University) Research Ethics Committee (Ref 2221).

Data collection.

Collection of data was conducted at the Food Industry Centre (Cardiff Metropolitan University). Self-reported practice and knowledge data were determined using a self-complete questionnaire, and attitudinal data were determined using a computer-assisted personal interview (CAPI). The questionnaire consisted of multiple choice questions based on knowledge and self-reported practices of the key practices associated with listeriosis control; response scales included 3-point “always, sometimes, never” scales. The CAPI technique allowed for the determination of older adult consumers' attitudes toward the key practices associated with lowering the risk of listeriosis. The CAPI included six sections using different response scales, including 5-point Likert-type scales to determine agreement and importance; and a variation of a visual analogue scale was used to determine likelihood. Each CAPI was audio recorded and took up to 60 min to complete.

Data analysis.

Data were entered and stored in a specifically designed Microsoft Access 2010 database and were analyzed using Microsoft Excel 2010 (Microsoft, Redmond, WA). Qualitative data analysis software NVivo 10 (QSR International Pty Ltd, Victoria, Australia) was utilized for the analysis of qualitative data. Descriptive and inferential statistics were conducted using SPSS Statistics 20 (IBM Software Group, Chicago, IL). Validity and reliability of the methods were determined to ensure reproducibility. The internal reliability of the Likert-type scales and a variation of a visual analogue scale used in the CAPI were determined using a Cronbach's alpha test for coefficient of reliability. A reliability coefficient (α < 0.86) indicating good internal consistency was determined.

Respondent demographic.

A total of 100 older adults from South Wales, United Kingdom, participated in the study. Eighty percent were female and reported being responsible for the majority of food preparation and storage practices in the home, 44% reported living in single-person households, and 56% lived with others (spouse or family). The majority (86%) of participants were “retired” and reported being from socioeconomic groups ABC1 (United Kingdom upper to lower middle class social status) (85%). The majority (65%) were between 60 and 69 years old, 28% between 70 and 79 years old, and 7% older than 80 years old.

Older adult consumers' awareness of listeriosis and associated food products.

The majority (88%) of older adults were able to name at least one pathogen associated with foodborne illness. The most frequently named pathogens when unprompted were Salmonella (62%) and E. coli (49%); only 20% named L. monocytogenes or listeriosis. Similarly, when prompted, the majority reported awareness of Salmonella (99%) and E. coli (100%); however, a greater proportion reported awareness of L. monocytogenes (87%) than when unprompted. Awareness of food products associated with L. monocytogenes was lacking; 55% were unable to identify any food products associated with L. monocytogenes, 9% identified one food product, 16% two, 8% three, and one person correctly identified six associated food products. Soft cheese and unpasteurized milk were the food products that older adults in this study most frequently believed to be associated with L. monocytogenes (see Table 1). There was a lack of awareness of the association of RTE meat and fish products with listeriosis. When prompted, 44% perceived the risk of listeriosis to be greatest for “pregnant women”; no participants perceived “themselves” to be at risk from L. monocytogenes, and less than a third (30%) perceived the “vulnerable elderly” to be at an increased risk of becoming ill with L. monocytogenes. Data indicated limited awareness of behaviors required to control the risks associated with L. monocytogenes: responses included food avoidance (18%), pasteurization of dairy products (6%), and adherence to use-by dates (3%).

TABLE 1.

Awareness of food products associated with L. monocytogenes among older adults

Awareness of food products associated with L. monocytogenes among older adults
Awareness of food products associated with L. monocytogenes among older adults

Knowledge of risk factors associated with listeriosis.

In the United Kingdom, the use-by dates on food products indicate the period following production during which a food product can be consumed safely; the majority (72%) of older adults knew that the use-by date was the date that was the best indicator of food being safe or not to eat. However, confusion existed because 14% of older adults thought that the “best before end” date indicated food safety and 13% either thought that all date labels had the same meaning or did not know which label was the best indicator of food being safe to eat.

Older adults' knowledge of the maximum storage length for food products associated with L. monocytogenes after opening or purchase was determined (Fig. 1). The majority of participants (56 to 84%) indicated that all food products associated with L. monocytogenes could be stored and remain safe for consumption for longer than the United Kingdom recommendation of 2 days after purchase or opening (15). Just over half (51%) were aware that, for example, smoked salmon should be stored for up to a maximum 2 days after opening. Overall, approximately two-thirds (69%) of older adults believed that a period longer than 2 days was the maximum safe storage length, with <21% believing RTE meat products could be stored for 5 days or longer after purchase or opening.

FIGURE 1.

Frequency of knowledge of recommended storage length for food products associated with listeriosis after purchase or opening.

FIGURE 1.

Frequency of knowledge of recommended storage length for food products associated with listeriosis after purchase or opening.

Close modal

Only 13% of older adults in this study knew that 5°C was the maximum operating temperature to ensure safe food storage. The majority (62%) stated that they did not know what the recommended maximum temperature should be, whereas 25% gave the incorrect answer. Cumulatively, 87% did not know the recommended maximum operating temperature for domestic refrigerators.

Attitudes toward risk factors associated with listeriosis.

Overall, the majority (73%) of older adults were found to have a neutral attitude toward food safety. Attitudinal scores of participants who reported living alone were significantly lower than those who lived with others (U = 951.5, z =−1.949, P < 0.05, r = 0.19). Attitudes toward practices that reduce the risks associated with cross-contamination, such as adequate hand washing after handling raw poultry, were more positive than attitudes toward practices that reduce the risk of listeriosis. Attitudes toward use-by dates were predominantly neutral; this indicates a lack of awareness, with 47% having a negative attitude and 42% having a positive attitude. In addition, 45% indicated that they personally do not need to follow use-by dates to judge that food is safe to eat. Around a third (32%) had a negative attitude toward use-by dates becoming invalid after opening, and an overall neutral attitude was expressed toward the wastefulness of throwing food out that is past its use-by dates (39% positive; 39% negative) (see Table 2).

TABLE 2.

Older adult attitudes toward recommended food safety practices

Older adult attitudes toward recommended food safety practices
Older adult attitudes toward recommended food safety practices

With regard to following storage instructions, the majority (85%) had a positive attitude toward it being essential to always store food according to storage instructions to ensure that it is safe to eat. Just over half (55%) indicated a positive attitude regarding RTE foods only being safe to eat for 2 days after purchase; however, the majority (62%) believed that the smell and appearance of food were reliable methods of ensuring that food is safe to eat (see Table 2).

Attitudes toward domestic refrigerator safe operating temperatures determined that the majority (88%) indicated a concern about the length of time the refrigerator door is kept open. Although 79% had a positive attitude toward the need to ensure that a refrigerator run at 5°C or lower to maintain the safety of foods, only 25% had a positive attitude toward the need to check the actual temperature of the refrigerator (see Table 2).

Analysis of qualitative responses during the CAPI indicate that, although older adults may be aware of the recommended practices to reduce the risks associated with listeriosis, such recommendations may not always be implemented or adhered to:

Checking the fridge temperature? I know it's somewhat important, although I don't do it. (participant 95, male aged 60 to 69 years)

Well if it's not too far past the use-by date, I've got to think about that one, 'cos, you know, well if it smells OK, I think then that it is wasteful to throw it, I would be concerned that that is wasteful. (participant 100, female aged 60 to 69 years)

I eat things beyond the “use-by” date, I do it a lot, because I go a lot on the way it looks and smells. (participant 14, female aged 60 to 69 years)

Self-reported risk factors associated with listeriosis.

The most frequently reported methods used to judge whether food would be safe to eat before consumption were to check the use-by date on food items (72%) or to consider when a food product had been opened (70%). A large proportion of older adults (<70%) also reported relying on senses of smell, taste, and appearance to check whether food was safe to eat. Although 80% of participants reported that smoked fish and shellfish would not be consumed beyond the use-by date, older adults indicated that other food products associated with listeriosis, including refrigerated packets of sliced cured meats (60%), packets of cooked sliced meats (50%), and prepacked refrigerated pâté (40%), would be consumed beyond the use-by date (see Table 3).

TABLE 3.

Reported consumption of food products after expired use-by date

Reported consumption of food products after expired use-by date
Reported consumption of food products after expired use-by date

Data in Table 4 indicate that older adults do not adhere to recommendations for consumption of RTE foods associated with L. monocytogenes within 2 days of purchase or opening. Although the majority (89 to 94%) reported that RTE cooked fish or shellfish would be stored and consumed within 2 days of either purchase from the deli counter or after opening, a large number of participants indicated that after purchase or opening, they would store soft cheese (70 to 83%), cooked sliced meats (67 to 70%), sliced cured meats (47 to 78%), and pâté (62 to 38%) beyond the recommended 2 days.

TABLE 4.

Self-reported storage of food products associated with L. monocytogenes after purchase or opening

Self-reported storage of food products associated with L. monocytogenes after purchase or opening
Self-reported storage of food products associated with L. monocytogenes after purchase or opening

Self-reported temperature monitoring of domestic refrigerators determined that 99% of older adults in this study believed their domestic refrigerator to be “cold enough”; however, 72% reported that they did not know the temperature of their home refrigerator. Of the 28% who reported they knew the temperature, it was determined that only 18% (5% of all older adults) stated a temperature in degrees (Celsius or Fahrenheit). Considerable confusion between the actual temperature of the refrigerator and the number displayed on the dial of the refrigerator was identified. The reported frequency of checking refrigerator temperature is illustrated in Figure 2. It can be seen that the majority of participants (55%) reported “never” checking their refrigerator operating temperature. The most reported frequency of checking refrigerator operating temperature was “every week” (16%).

FIGURE 2.

Reported frequency of checking refrigerator operating temperature (n = 100).

FIGURE 2.

Reported frequency of checking refrigerator operating temperature (n = 100).

Close modal

Statistical analyses were conducted to determine potential differences between participant demographic and self-reported practices using the chi-square test for independence. A greater percentage of female participants (79%) reported that they “always” check the use-by date on food products than male participants (45%); (χ2 (2, n = 97) = 13.890, P < 0.01, Cramer's V = 0.378).

Comparison of cognitive and behavioral listeriosis risk factors.

A cumulative comparison of knowledge, attitudinal, and self-reported findings from this study according to the three key practices associated with listeriosis is presented in Table 5. Note that, although some older adults were knowledgeable of recommendations, failure to reported implementation was widespread.

TABLE 5.

Cumulative comparison of older adults' knowledge, attitudes, and self-reported practices relating to the three key practices associated with the risk of listeriosis in the domestic kitchen

Cumulative comparison of older adults' knowledge, attitudes, and self-reported practices relating to the three key practices associated with the risk of listeriosis in the domestic kitchen
Cumulative comparison of older adults' knowledge, attitudes, and self-reported practices relating to the three key practices associated with the risk of listeriosis in the domestic kitchen

Significant associations of older adult consumers' cognitive and behavioral factors in relation to each of the key behaviors for listeriosis risk reduction are summarized in Table 6. A negative attitude toward the importance of use-by dates was significantly associated (P < 0.001) with self-reported consumption of food beyond the use-by date. No significant associations (P > 0.05) were determined between knowledge of use-by dates and self-reported practices. Associations were determined between attitudes and knowledge of safe domestic refrigerator operating temperatures (≤5°C); older adults who were knowledgeable of recommended refrigeration temperatures were significantly more likely (P < 0.001) to self-report that refrigerator temperature would be checked, and older adults who had positive attitudes toward the importance of refrigeration were significantly more likely (P < 0.001) to self-report that refrigerator temperature would be checked. Similarly, with regard to consumption of RTE food products within 2 days of opening, older adults with knowledge of the maximum recommended storage length after opening were significantly more likely (P < 0.05) to self-report that RTE food products would be consumed within 2 days of opening, and those with a positive attitude were significantly more likely (P < 0.05) to self-report that RTE food products would be consumed within 2 days of opening.

TABLE 6.

Statistical associations determined between cognitive findings relating to listeriosis risk factors

Statistical associations determined between cognitive findings relating to listeriosis risk factors
Statistical associations determined between cognitive findings relating to listeriosis risk factors

Cumulative findings from this study show that, although some older adults were knowledgeable of recommended food safety practices to reduce the risks associated with listeriosis, self-reported failure to implement such practices was widespread. Furthermore, significant associations were determined between older adults' self-reported practices according to knowledge of key practices and their attitudes toward such practices.

Older adult consumers' awareness of listeriosis and associated food products.

Older adult consumers in this study indicated good awareness of Salmonella (99%) and E. coli (100%); such findings correspond with previous data about consumer awareness of these pathogens (11, 57, 59). Although many reported awareness of L. monocytogenes (87%), more than half (55%) were unaware of food products associated with L. monocytogenes prevalence; foods most frequently mentioned as associated with L. monocytogenes were soft cheese (36%) and unpasteurized milk (33%). Despite being ≥60 years old and, thus, considered to be at an increased risk of listeriosis, participants (44%) thought pregnant women were at the greatest risk of listeriosis. None of the participants perceived themselves to be at risk from L. monocytogenes, which suggests perceived personal invulnerability; however, research is needed to determine older adults' perceptions of risk, control, and responsibility in respect to food safety. Only 3% identified adherence to use-by dates as a control measure for listeriosis. Similarly, previous research suggests that fewer older adult consumers have heard of Listeria than other pathogens and that the majority are unaware of risk-reducing behaviors (37).

Following use-by dates on unopened prepacked RTE food products.

The use-by dates on food products in the United Kingdom are indicators of food safety. It is essential for consumers to adhere to use-by dates on unopened RTE food products because they are calculated to ensure that 100 CFU/g levels of L. monocytogenes are not exceeded in food products that can support growth from the time of production to consumption (10, 58). Previous consumer food safety research based on respondents from the general population found that 49 to 62% of consumers knew that use-by dates were the best indicator of food safety (25, 44), and 46% of consumers reported to “never” eat food beyond its expiration date (39). Previous data on consumer attitudes toward adherence to use-by dates indicated that 73 to 75% considered it very important to avoid the consumption of foods with expired dates (57). Although the majority (72%) of older adults in this study indicated awareness that the use-by date was the best indicator for food safety, 66% failed to express a positive attitude toward avoiding the consumption of food beyond the use-by date; only 39% believed that it was essential to “always” eat food by the use-by date to ensure the safety of food. Some older adults expressed concerns regarding the potential wastefulness caused by adhering to use-by dates; indeed, the perception of wastefulness may increase the risk of foodborne listeriosis due to the prolonged storage of RTE foods, which may allow for critical limits of L. monocytogenes to be exceeded prior to consumption.

Contradictions were noted regarding use-by dates. Even though 62% reported to “always” take note of the use-by date of food labels, only 42 to 43% reported that they were unlikely to consume soft cheese 3 days beyond and cooked meat from a sealed pack 2 days beyond the use-by date. In addition to this, 57% of older adults self-reported that they do consume food that have expired use-by dates. Previous data indicate that 18 to 40% of consumers reported never eating food products beyond the expiration date (17). Older adults in this study frequently reported consuming RTE food products commonly associated with L. monocytogenes beyond the expiration of the use-by date, including sliced cured meat (60%), sliced cooked meat (50%), pâté (40%), and prepared salad bags (65%). A significantly greater (P < 0.01) percentage of female participants (79%) reported to “always” check the use-by date on food products than male participants (45%); such demographic differences in self-reported practices may be utilized to inform the development of targeted consumer food safety education.

Although knowledge of use-by dates was determined to be greater among the older adult consumers of this study than among consumers from the general population (25, 44), self-reported consumption of food products beyond the use-by date was reported by a larger proportion of older adults (39). Unsurprisingly, negative attitudes toward the importance of use-by dates were significantly associated (P < 0.001) with self-reported consumption of food beyond the use-by date. Such findings have implications for the development of food safety education to influence attitudinal change among older adults rather than solely raising awareness and increasing knowledge.

Ensuring that refrigerator operating temperature is ≤5.0°C.

Given the ability of L. monocytogenes to survive and grow at refrigeration temperatures (1), refrigeration temperatures are critical in controlling L. monocytogenes (33); therefore, refrigeration temperatures ≤5.0°C are recommended to safeguard consumers from the risks associated with listeriosis (15, 54). Previous food safety research involving consumers from the general population has determined that large proportions of consumers lack knowledge of safe refrigeration temperatures. Indeed, 93% of Irish consumers (22), 79 to 84% of United Kingdom consumers (21, 51), 68% of Australian consumers (34), and 44% of Slovenian consumers (35) reportedly lacked knowledge of recommended refrigeration temperatures. Previous studies indicate positive consumer attitudes toward refrigeration, with 97% of consumers believing it to be important to keep a refrigerator at the correct temperature (22). However, self-reported data show that 65% of consumers in Trinidad (5), 71% of United Kingdom consumers (60), and 75% of Australian consumers (34) reportedly do not measure or have never checked the operating temperature of their refrigerator. Failure to ensure safe refrigeration temperatures may have implications for food safety.

Although the majority of older adults (79%) had a positive attitude toward refrigeration temperatures being essential to maintain food safety, fewer (52%) had a positive attitude toward the importance of actually checking that the refrigerator is operating between 0 and 5.0°C. The majority of older adults in this study (72%) reported that they did not know the operating temperature of their domestic refrigerator, 65% reported to “never” check that their refrigerator is operating between 0 and 5.0°C, and 44% reported that they do not check whether their refrigerator is cold. Additionally, findings indicate that the majority of older adults (87%) do not know that 5.0°C is the recommended maximum operating temperature of a domestic refrigerator to ensure the safety of food.

Although older adult knowledge of safe refrigeration temperatures concurs with previous research indicating that the majority of consumers from the general population are also unaware of recommended temperatures (21, 22, 51), attitudes toward the importance of refrigeration and checking refrigeration temperatures were less positive among older adults than among the general population (22). Self-reported checking of refrigerator operating temperature among older adults corresponded to that of the general population (5, 60). Significant associations (P < 0.001) were determined between knowledge and positive attitudes toward recommended refrigeration temperatures and self-reported frequency of checking refrigerator operating temperatures. Consequently, such findings have implications for food safety educators because older adults lack awareness of refrigeration temperatures, and failure to check operating temperature may result in older adults unintentionally storing RTE food products at potentially unsafe temperatures that can increase the risk of listeriosis.

Consuming RTE food products within 2 days of opening.

Modified atmosphere packaging is commonly used to extend the shelf life of RTE food products (6, 52); however, after it is opened, the removal of the modified atmosphere will result in increased levels of L. monocytogenes (53). It is reported that the risk of listeriosis can be decreased by reducing the storage length of delicatessen meat (33, 55). Consequently, it is recommended that RTE food products should be consumed within 2 days of purchase or opening (15). There is a lack of consumer food safety data relating to the adherence to storage duration guidelines, particularly in relation to consumer attitudes (17). However, previous data indicate that the majority of consumers (96%) were aware that the improper storage of food may represent a health hazard (3) and 40 to 69% reported “always or usually” following manufacturer's instructions for storage of food products (22, 44); furthermore, the majority of consumers reported consumption of foods within 2 days of purchase or opening (39).

This study has undertaken an in-depth cognitive analysis of food storage practices after RTE food packaging is opened. Findings indicate that the majority (68%) of older adults had positive attitudes toward the importance of consuming RTE food within 2 days of preparing, opening, or purchase, but knowledge of recommended safe storage length after opening RTE food was lacking, with 56 to 84% believing that RTE foods associated with L. monocytogenes could be stored beyond the recommended 2 days after purchase or opening. Furthermore, many older adults reported prolonged storage of RTE food beyond the recommended 2 days in the home, with only 28% reporting that RTE food would be consumed within the 2 days. In addition, older adults reported that RTE food products from the delicatessen counter (70% soft cheese and 47% sliced cured meat) would be stored and were intended for consumption beyond the recommended 2 days after purchase; prepacked RTE foods were reported to be stored for durations exceeding recommendations (83% soft cheese, 78% sliced cured meat, 70% sliced cooked meats, and 62% pâté). Findings suggest that older adults frequently consume RTE food products associated with L. monocytogenes subjected to prolonged storage, which may increase the risk of listeriosis.

A comparison of the results from this study specific to findings relating to storage of opened RTE food products was limited due to the lack of previous data. Although positive attitudes toward the importance of storage and consumption of opened RTE food were expressed by the majority of older adults, self-reported data did not concur with recommended practices. Storage of RTE food products for prolonged times was reportedly widespread among older adults; this does not agree with previous research, in which the majority of consumers from the general population were reported to consume RTE food products within 2 days (38). Older adult knowledge and positive attitudes toward consuming food within 2 days of opening or purchasing were significantly associated with the self-reported frequency of consuming food within recommended time limits; such findings can be utilized to design and develop food safety education to increase awareness and improve attitudes to enable behavioral change when storing RTE food products in the home after opening.

In conclusion, although the majority of older adults reported awareness of listeriosis, only approximately a third of them were aware of associated food products. Cumulatively, older adult consumers' knowledge of key practices required to reduce the risks associated with listeriosis was comparable to that of consumers in the general population. However, self-reported practices relating to use-by date adherence and storage of opened RTE food showed lower adherence among older adults than data suggest for the general population. Furthermore, older adults' attitudes toward the three key risk-reducing storage practices were more negative than those of the general population. Such findings can have implications for the safety of food in older adults' domestic kitchens.

This study has addressed the lack of older adults' food safety cognitive data by combining data collection methods and measures and has also identified the potential risk factors associated with listeriosis in older adults' domestic food safety practices. Self-reported malpractices among older adults were determined to be greater than the literature suggests for consumers from the general population.

There is a need to improve older adults' food safety behavioral practices related to the key storage practices to reduce the risk of listeriosis; cognitive data such as that collated in this study is needed to inform development of targeted food safety educational initiatives. To enable a behavioral change to reduce the potential risks associated with listeriosis among older adults, there is a need to make them aware of the potential risk from L. monocytogenes associated with practices that they may fail to implement in the domestic kitchen.

However, this study shows that there are no significant associations between older adults' knowledge and their attitudes toward the key food safety practices required to reduce the risks associated with L. monocytogenes. Furthermore, attitudes were significantly associated with self-reported practices. Consideration is given to the impact of attitudes on the implementation of food safety practices because consumer attitudes have been determined to be significant determinants of their behaviors (49).

Given that attitudes are a determinant of behavior, findings from this study regarding older adults' attitudes toward use-by dates, storage durations after opening packaging, and refrigerator operating temperatures were significantly associated with self-reported practices. Therefore, an initiative to change attitudes may help to increase implementation of risk-reducing food storage behaviors. Consequently, to develop targeted consumer food safety education to reduce the risks of listeriosis among the older adult age group by improving the implementation of food safety practices, educational efforts must change older adult consumers' attitudes and not only increase knowledge.

Furthermore, the industry may be able to reduce the risks associated with listeriosis through the development of intelligent refrigerator designs; the incorporation of integral thermometers and accurately calibrated thermostats would help prevent inadequate storage temperatures in the home, without requiring behavior modification such as purchase, usage, and calibration of a thermometer. Similarly, the availability of smaller food packages may prevent consumers from subjecting RTE food products to prolonged storage after opening.

Potential limitations in this study include the potential for social desirability bias and issues relating to the overreporting of “good” behaviors determined from self-reported practices; research indicates that discrepancies may exist between self-reported practices and actual behaviors (12, 13, 45). Despite this, considerable proportions of older adult consumers reported implementation of food safety malpractices associated with listeriosis. These findings show the need for food safety communication initiatives because many participants in this study reported malpractices.

There is a need to combine the findings of this research study with “in-home” observed domestic kitchen behaviors associated with listeriosis. Such data would provide more understanding of how older adults' cognition of listeriosis risk factors affects the handling of RTE food products and implementation of food safety behaviors in the domestic kitchen, which would help food safety educators design and develop targeted food safety education for older adults to reduce the incidence of listeriosis.

This study was supported by research funds from the Vice Chancellor's Doctoral Award from Cardiff Metropolitan University. The authors acknowledge Prof. Louise Fielding (1968 to 2013) for her support throughout the project.

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