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Consumer handling of chilled foods: Perception and practice
Consumer handling of chilled foods: Perceptions and practice Judith Evans Food Refrigeration and Process Engineering Research Centre, University of Bristol, Churchill Building, Langford, BS18 7DY, U K R e c e i v e d 16 A p r i l 1992
A survey has been made of 252 households in the UK to evaluate consumer handling of chilled foods. The survey has provided information on the shopping habits of the households in terms of the types of shops they use, their shopping frequency and transportation arrangements. Data are also presented on the consumer's attitude to and knowledge of food safety and storage times. By using data obtained from a study of the chilled products present in the householders' refrigerators, a comparison has been made between the consumer's expectations in terms of storage life and their practice. (Keywords: chilled foods; consumer storage; domestic refrigerators)
Manipulation des produits r&rig6r6s par les consommateurs: Perception et pratiques On a effectub une enqu~te auprOs de 252 mbnages au Royaume Uni, sur la fagon dont ils manipulent les produits rbfrigbrbs. Des informations ont btb obtenues sur les habitudes des consommateurs lorsqu'ils font leurs courses, et plus prbcisbment sur le type de magasins auxquels ils se rendent, sur la fr~quence de leurs achats et sur les moyens de transport qu 'ils utilisent. Des donnbes sont bgalement fournies sur l'attitude du consommateur et sur sa connaissance de l'innocuitb et de la durbe de conservation des aliments. En utilisant les donnbes obtenues lots d'une btude sur les produits rbfrigkrbs trouvbs dans les rkfrigbrateurs des mbnages, on a comparb les diverses attentes des consommateurs en termes de dur~e de conservation, ainsi que leurs habitudes respectives.
(Mots cl+s: produit r&rig6r6; entreposage du produit chez le consommateur; r6frig6rateur domestique)
Products that require refrigeration make up 63% of the contents of the food basket of the average European ~. Only 3% of the basket's contents is sold in a frozen form, which means that chilled or flesh foods make up 60%. The terms chilled and flesh encompass a wide range of foods with optimum storage temperatures from - I * C for flesh fish to approaching 18°C for certain exotic fruits. In the past few years there has been considerable publicity surrounding cases of food poisoning associated with the consumption of certain chilled foods. This has ranged from S a l m o n e l l a in eggs and poultry products to Listeria m o n o c y t o g e n e s in ready meals, prepared salads and mould- or bacteria-ripened soft cheese. The importance of maintaining strict hygiene and temperature standards during the production, storage and retailing of chilled foods was highlighted in the U K by the introduction of the Food Hygiene (Amendment) Regulations 1990. However, the requirement for good temperature control and handling procedures does not stop when the food leaves the retail store. The treatment of the chilled food by the consumer and their overall attitude to the product is an important final step in the cold chain. Since little data could be found on the consumer handling of chilled food in the UK, the Ministry of Agriculture Fisheries and Food (MAFF) funded a consumer survey. The full study 2 has just been published and this paper gives details of some of the data obtained on consumer perceptions and practice. A second paper in this journal will provide data from the study of the temperature of foods in domestic handling. The survey population consisted of 252 households selected from the towns of Weston-super-Mare, Bridgwater and Taunton 0140-7007/92/0502904)9 © 1992 Butterworth-Heinemann Ltd and IIR
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in the south-west of England. The survey was divided into two parts: the first between September and December 1989 and the second between February and May 1990. The aim was to reflect varying seasonal ambient weather conditions. Each part of the survey consisted of a different group of 126 households split evenly between the three towns. The three towns of Weston-super-Mare, Bridgwater and Taunton were selected because of their varying demographic and social status. Weston-super-Mare is a predominantly better-off retirement area with high-status non-family areas, affluent suburban housing and older housing of intermediate status. Bridgwater consists mainly of council estates and older housing of intermediate status. Taunton has a variety of older housing, council estates and high-status non-family areas, affluent suburban housing and better-off retirement areas. Participants were selected by CACI Market Analysis Division (a commercial market research company) as a one in n sample from the electoral registers covering the three towns, with the aim of producing a representative range of social and economic groups within each town. In the initial part of the survey questions dealt with shopping habits for chilled food, including details such as the frequency of shopping, distances travelled, time taken and the shops that were used. Participants were also asked about the length of time they would expect to be able to store various categories of chilled food after purchase and their attitude towards and knowledge of food poisoning. Participants were then asked whether a list could be made of the contents of their refrigerators with more detailed questions being asked about any meat
Consumer handling of chilled foods: J. Evans (including all cooked and raw red and white meat), fish (all fresh and cooked fish) or fat (cheese, dairy and vegetable fats) items present. Questionnaire responses were divided into part of survey (1 or 2) and town (Weston-super-Mare, Bridgwater or Taunton) and tested to determine whether answers were consistent throughout the survey. Owing to the unbalanced nature of the questions, responses required stabilizing by means of a variance stabilizing (arcsin) transformation to produce the transformed data x where:
0.79% 15.48% 26.19%
J
< onceJweek OncMweek
Twiee/wcek 3-4 times/week [ ] 5-7 times/week
23.81%
x = (-!0--00)arcsin {( % p°pulati°nlwtlO0 ] J Stabilized questionnaire data were examined by analysis of variance (ANOVA) to determine whether statistical differences existed between question responses in part and town. If differences between part and town were not significant, answers were combined and considered together.
33.73% Figure 1 Number of shopping trips per week Figure 1 Nombre de dbplacements par semaine pour faire des courses
Questionnaire data
Household shopping patterns The initial questions to participants were designed to provide an easy introduction to the survey and dealt with people's general shopping patterns. Initially participants were asked how often each week they visited the shops for food. This question was asked to determine the total number of days the household (inclusive of all members) shopped for chilled food per week. If the household shopped at irregular intervals, they were asked to state the average number of days per week they would usually visit the shops. Responses included both shopping trips for small quantities of food, such as bread or milk, and also larger weekly food purchases. ANOVA revealed differences between answers (P < 0.01), but no variations between part of survey or town. Therefore, question answers from both parts and towns could be combined and considered together. With two exceptions all the households (99.2% of the survey population) shopped on at least one day per week for chilled food. The greatest number of respondents (33.7%) shopped for food three to four days per week, closely followed by 26.2% who shopped five to seven days per week and 23.8% who shopped on two days. Few households (16.3%) shopped for food less than twice per week
(Figure 1). Participants were next asked to state on which day or days they did their shopping. The amount of shopping was divided into larger amounts, defined as the purchase of a carrier bag or more of food, and smaller quantities, defined as less than a carrier bag of food. ANOVA demonstrated significant differences in answers (P > 0.05), but no differences between part or town (P > 0.05). Larger quantities of food were bought by 97.7% of the householders interviewed: 73.8% of these shopped once per week and 23.0% visited the shops twice or more per week. A small proportion (0.8%) shopped at intervals of greater than once per week, most usually monthly or every two weeks. The remaining 2.3% of households stated that they never bought large quantities of food. Larger quantities of food were most often bought on Thursday, Friday or Saturday, with Friday being the most popular day (Figure 2).
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Variable
Sunday Saturday Friday
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Thursday N
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.
~
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Wednesday Tuesday Monday I
0
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40
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50
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I
60
*
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70
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80
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90
"
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Number of occurrences Figure 2 Figure 2
Day of week on which shopping was done Jour de la semaine durant lequel les courses sont effectubes
Most households shopped for small quantities of food on a variable basis, as required. Only 15.5% of households stated that they never bought small amounts of food, whereas most people visited shops for small amounts once per week (Figure 2). Questions were also asked to determine the types of shopping outlets most commonly visited when buying food. If participants shopped at more than one outlet for a particular food type, they were asked to state which type of shop they used most regularly, and the one they used as a second choice. It was clearly stated that this question only encompassed chilled foods and did not include frozen foods. Participants were not prompted in their replies and usually responded to the question by stating specific shops that they visited, which were then placed within the relevant category. ANOVA of participants' first and second choice shop types in part and town revealed statistical differences (P < 0.001) between shops where food was bought and differences (P < 0.001) between first and second choice answers. Variations between towns or parts were not significant. Rev. Int. Froid 1992 Vol 15 No 5
2.91
Consumer handling of chilled foods." J. Evans 3.57% 9.52% i [] [] []
I day ago 2 days ago 3-4 days ago 5-6 days ago More than 7 days
> 5 miles
I
> 1, up to 5 miles
19.84%
I~1 Small
51.59% > half,up to 1 mile
Up to halfa mile ID.~070
0
20
40
60
g0
100
120
140
Numberof occurrences Figure 3 Figure 3
Length of time since last shopping trip
Temps qui s'est kcoulb depuis les derniers achats
As a first choice over 40% of participants preferred to buv meat, meat products, fish, eggs, dairy and dessert products in a supermarket. Salad items were preferably bought in a small grocer or local shop. A number of people also bought meat and fish in specialist shops such as butchers or fishmongers and eggs from a farm. As a second choice most participants shopped in either a supermarket, a small grocers or a specialist shop. A maximum of 14.3% of interviewees bought food in more than one type of shop, probably reflecting the easy availability of first choice shops in the towns surveyed. Over half (51.6%) of the householders interviewed had shopped for food on the day of or the day before the survey. Few households (3.6%) had not shopped within the last seven days, reflecting the trend for shopping once or more per week. Statistical differences in answers were found (P < 0.001), but differences between part or town were not significant (Figure 3). To obtain a general picture of shopping habits participants were then asked a series of questions about the distance they travelled to buy chilled food and the method of transport used. Participants who bought food in several locations or used varied methods of transport could answer within more than one category. ANOVA demonstrated significant differences (P < 0.05) between answers, but not between part or town. Most participants in the survey did their main shopping between one and five miles from their homes. Only one of the householders (0.4%) bought food from shops within more than one of the distance categories. Few householders travelled more than five miles to shop. Of the 246 households who shopped for large amounts of food, 85.3% always or occasionally used a car to transport their main shopping home. Only eight people (3.2%) used more than one form of transport to bring larger amounts of shopping home (Figures 4 and 5). In all three towns surveyed there was at least one large supermarket within one to two miles of the town centre. Travelling distances would probably have been greater if rural areas had been included in the survey. Small quantities of food were generally bought close to the home, again reflecting the availability of shops in the towns surveyed. A small proportion (5.2%) of householders shopped within two of the distance categories. Most householders (87.6%) who bought small quantities of food transported it home by either foot or car. Forty292
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Figure 4 Figure 4
Distance to shops
Distance s~parant les consommateurs des magasins
Motorbike
Cycle
U I~-ge [] Sman Taxi
Foot
0
20
40
60
80
100 120 140 160
180 200 220
Number of o c c ~
Figure 5 Figure 5
Mode of transport used
Mode de transport utilisb
six people in this category (21.6%) used more than one mode of transport to bring food home (Figures 4 and 5). The time required for participants to transport chilled food home from the shops was also investigated. Significant differences (P < 0.001) were found between all question answers, but differences between part or town were not apparent. If delays due to visits to friends, relations or work patterns were not taken into account, the vast majority (96.3%) of households who did a main shop said that they reached home within half an hour of leaving the shop. This again reflected the availability of suitable shopping within easy travelling distance in the towns surveyed. No households required more than two hours to bring food home. Small quantities of food were generally brought home within half an hour of purchase. However, a small proportion of food required more than two hours to be brought home and this was generally due to householders shopping further afield because of work or social commitments (Figure 6). Delays in bringing food home were rare (Figure 7). Most households (68.7%) always brought food straight home from the shops. Only 1.2% of households were
Consumer handling of chilled foods: J. Evans 1.19% > 4 hours
to 4
I
[] [] []
hours
Cool box Cool bag None
[] Large
to 2 hours
Small Italf to 1 hour
I:.
20
.....................
40
60
80
100 120 140 160 180 200 220 240
87.30%
Number of occurrences
Figure 6 T i m e to b r i n g f o o d h o m e f r o m s h o p s F i g u r e 6 Temps nbcessaire pour emporter les achats, du magas& au domicile
1.19% 6,32%
~! Always [ ] Very Frequently [ ] Sometimes
[] Rarely [] Nev~ 9.49%
Figure 7
Frequency of delays
Figure 7
Fr~quence des retards
always delayed, and 6.3 % very frequently delayed, whilst transporting food home. It must be stressed that some participants who delayed bringing food home stored perishable foods in a refrigerator during the delay period. During the journey home the vast majority (87.3%) of people did not use any means of protecting food from temperature gains during transportation. Only 12.7% of participants stated that they used either a cool bag or box to transport some of their food home (Figure 8). The reason for such a low utilization of protective bags or boxes could be due to short journeys (less than half an hour) home. However, the small number of people who required between one and four hours to transport food home did not always use protective boxes or bags. These people could be unaware of the potential problems of transporting food home in high ambient temperatures.
Storage and food safety in the home After determining the way in which chilled products were bought and how they were transported, participants
Figure 8
Use of cool bags/boxes
Figure 8
Utilisation de sacs ou de boites isothermes
were asked a series of questions about food storage and food safety in the home. Participants were first asked to estimate the storage life of a range of popular chilled food items. It was stressed that the foods were all chilled and not frozen and that the foods were initially of good quality and were of the type generally bought by the householders. If participants were unsure of an answer they were given a chance of stating that they did not have an opinion. ANOVA of all answers revealed no statistical differences (P > 0.05) between parts or towns. However, significant variations (P < 0.001) in actual answers were found, indicating that individual opinions on the refrigerated storage life of the chilled foods were variable. Most foods (prepared meals, pizza/quiche, cold pies, pate, sausages, raw poultry, cooked poultry, cooked meat and raw meat) were thought to store well for two days. However, a number of people considered that these foods could be stored for longer than seven days and sometimes as long as 30 days. Most participants thought that bacon, eggs, cottage cheese and salad could be stored for up to a week, although a few people considered that storage of up to 30 days was acceptable. Fresh fish was generally considered to store least well, with most participants stating that they would only store fish for one day or less. Most participants were prepared to give an opinion on the storage life of the chilled foods considered, although a small percentage (at most 7.5%) stated that they did not have an opinion or did not know the answer. The range in anticipated storage life for different food types varied considerably. Opinions on the storage lives of individual foods ranged from half a day to seven days (range six and a half days) for cold pies and sausages to between half a day and 30 days (range 29.5 days) for pate, bacon and cottage cheese. The minimum storage life for all foods except eggs (minimum storage life of two days) was either a quarter or half a day. The modal storage life ranged from one to seven days with 10 out of the 15 foods having a modal storage life of two days. A small number of householders thought that they could store chilled foods for periods of up to 30 days. Bacon, cottage cheese, eggs and pate were all thought to be
Rev. Int. Froid 1992 Vo115 No 5
293
Consumer handling of chilled foods: J. Evans
Minimum Eggs Sausages ~
Salad
Eggs
Salad ~ !
Raw poultry Raw meat Pizza Pate Cooked poultry
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Cottage cheese ~ ~ i ! : :
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Cooked meat
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Cold pies Bacon Prepared meal
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Burger Pizza :-:..~:..~.:~.-....-..-:-:-:il "::.!:~¢i.::~""::E:7 Raw poultry i#..%-~!:~"~!'! Fish Sausages Cold pies 0
1 2 3 4 5 6 7 Days
10 20 Days
30
Figure9 Minimum,modal and maximum storage lives stated by householders Figure 9 Durbes de conservation minimale, modale et maximale, avancdes par les consommateurs acceptable after this period by a small proportion of participants. Cooked meat and poultry were also thought to store for up to 21 days by a few householders
14.68%
(Figure 9).
Participants were next asked a series of questions to gauge their concern and knowledge of food poisoning. The degree of concern about food poisoning was assessed on a five-point scale ranging from very concerned to not at all concerned. Answers were restricted to concern about food from shops and did not include concern about food poisoning due to restaurant or fastfood-type meals or food. If replies from participants did not directly fall into one of the five categories further questions were asked to assess the individual's degree of concern about food poisoning. The answers people provided were statistically different (P < 0.001), but did not vary between parts or towns (P > 0.05). The greatest number of participants (56.7%) were either only slightly concerned or not at all concerned about food poisoning. However, 31.7% of participants admitted to being concerned or very concerned about food poisoning (Figure 10). All participants were asked to name foods that they considered might constitute a food poisoning risk. Individuals could name as many foods as they wished. Significant differences (P < 0.001) were found between the types of food named as presenting potential food poisoning problems, but these did not vary in parts or towns in the survey. Most of the respondents (73%) considered poultry to be a problem. Raw poultry was considered to be a greater risk than cooked poultry. Meat was also considered likely to cause food poisoning, with 66.7% of participants mentioning either raw or cooked meat as a potential problem. It was interesting to note that although poultry and meat were considered a likely cause of food poisoning, participants did not necessarily consider that these foods had short storage lives. It is 294
Int. J. Refrig. 1992 Vo115 No 5
[]
Vczyconcerned
[]
~
[ ] ~
y
coacea~
[ ] Slightly co~aeerned [ ] Not at all concerned 40.87% 17.06%
15.87%
Figure 10 Concern about food poisoning Figure 10 Preoccupation par rapport aux intoxications alimentaires therefore possible that people did not associate storage time as being related to any food poisoning problem. Foods such as eggs, yogurt and cook-chill meals, on which media attention had recently focused, were not mentioned as much as might have been expected. These foods were only mentioned by a maximum of 16.7% of participants, perhaps demonstrating the transient nature of food scares (Figure 11). Participants were asked to name as many germs/bacteria as possible. Answers were never prompted and only the clear name of a bacterium accepted. Statistical analysis of the answers revealed differences (P < 0.001) between the numbers of bacteria that participants could name. Differences between parts and towns were not significant (P > 0.05). Most householders (61.1%) could name two or more bacteria, the most common being Salmonella and Listeria. Only a small number of partici-
Consumer handling of chilled foods: J. Evans Poultry-raw Meat~ Poultry-eo~ed Meat-raw Pate Eggs Fish Cook-chill foods
Cryptosporidium Enterococcus Campylobacter Clostridium Streptococci
Cheese
Pies Dairyp~ucts Sausages
E. Coli Staphylococci
Sd~k Yogurt Sandwiches Fruit Bacon Leftovers Jelly l r ~ i ~ t ~ food
Listeria Salmonella
it~
.
. ,
-
10
33 43 5;
70 8;
Figure 13 Figure 13
Number of
20
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-
40
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-
60
, 70
-
80
Bacteria named by participants Bact#ies cit&s par les participants
.............. Eggs
0 1
Yog,ul
Ch=se ~..cod=d Pies Coldr~t R ~ mest Cook-chillf~ds B=on Sausages
0.40%
•2 []3 1"-i4
Fish
i5 []
"
Foods considered a risk Aliments consid#bs "'~ risques"
Number of bacteria named
[] []
|
% of surveypaticipanlswho could namebacteria
o l; Figure 11 Figure 11
m
Botulinum
DelryIxed=ts
6
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Pate
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Cheese ~ , ~ a Poultry-ceoked ' ,~mm~ Dairyproducts ' im m Eggs Coldmeat ~ R | [] | Part 1 Red meat ] Part 2 | Pies' Fish | C o o k - c h i l l foods | Bacon 13 I; 2() ~ 33 Numberof cccmrerr.es Numberof occurrences m
-
-
-
~
33
Figure 14 Foods that participants had stopped buying due to concern about food poisoning Figure 14 Aliments que les participants ont cessb d'acheter par crainte
d'intoxication alimentaire
9%
Figure 12 Number of bacteria named Figure 12 Nombre de bact#ies cit&s
pants (2.4%) could name four or more bacteria and 13.1% of the survey population could not name any
(Figure 12). The best known bacteria were Salmonella (which 78.9% of those surveyed could name), Listeria (61.5%) and Botulinum (16.2%). These bacteria were probably familiar due to media coverage at the time of the survey, which dealt with food safety issues. Few other bacteria could be named by participants in the survey (Figure 13). Participants were asked whether they had stopped buying any foods due to concern about food poisoning. Only answers that directly related to worries about food poisoning were included. Participants were not limited in the number of foods they could name and the answers were never prompted. ANOVA revealed significant differences (P < 0.001) between the numbers of people who had stopped buying
the foods mentioned. The numbers of people who had stopped buying the foods were not significantly different (P > 0.05) in the three towns surveyed. There was, however, a significant (P < 0.05) interaction between food type and part, which was due to differences in ranking of foods in parts 1 and 2. The greatest number of participants (69%) stated that they had not stopped buying any foods due to worries about food poisoning. In part 1 of the survey a greater number of people were worried about buying cheese, eggs, pate and yogurt; all foods on which the media had recently focused. In part 2 the number of people who stated that they no longer bought these products was greatly reduced, except in the case of cheese, which was still considered a potential health risk by 7.9% of those surveyed (Figure 14).
Chilled food storage in domestic refrigerators Two hundred and forty-eight (98.4%) households agreed to list the contents of their refrigerators. Questions were asked to determine, for the individual fish, fat and meat items present, the purchase date and consumption date, the time taken to bring the item home and place it in a refrigerator and the method of transport. If the food was packaged, the best-before or eat-by date was also noted. The data were analysed to determine:
Rev. Int. Froid 1992 Vo115 No 5
295
Consumer handling of chilled foods: J. Evans 10000
Other
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Figure 15 Transport used to bring meat, fish or fats home
-
100
,
90
80
70
Figure 15 Mode de transport utilisk pour rapporter la viande, le poisson ou les aliments ~ teneur en graisse jusqu'au domicile
1. the method used to transport food home; 2. the time required to bring food home and to place it in a refrigerator; 3. storage life of refrigerated foods. The third category was subdivided into (a) stated storage life of food versus shelf life and (b) stated storage life of food versus storage period stated in questionnaire.
The method used to transport food home The method used to transport home the fat, fish and meat items stored in each householder's refrigerator was noted. A number of householders could not remember the exact way in which they had bought items home and therefore not all fat, fish or meat items stored in refrigerators were included. A N O V A demonstrated that significant differences (P < 0.001) existed between modes of transport, but not between part or town. By far the greatest number of householders transported fat, fish or meat items home by car (77.2%). The second most popular method of transport was by foot, which accounted for 13.2% of items examined. Few items (less than 4% in each case) were transported by bus, train, bicycle, taxi or other methods (Figure 15).
The time required to bring food home and to place it in a refrigerator The time required to bring fat, fish or meat items home from the shops and the time required to place the food items in the refrigerator were analysed. A number of participants could not remember times required to bring certain foods home and therefore not all foods itemized were included. No differences were found between food types or times required to bring food types home in either part or town (P > 0.05). The overall mean time required to bring food home was 36.4 minutes with a standard deviation of 13.3 minutes. This extended to 42.8 minutes with a standard deviation of 18.7 minutes by the time the food had been placed in a refrigerator. The greatest number of items were transported home within 10 minutes and were placed in a refrigerator within 13 minutes. However, the
296
Int. J. Refrig. 1992 Vo115 No 5
60 50 40 % of answers
30
20
10
0
Figure 16 Time to transport food to home Figure 16 Temps nbcessaire pour revenir au domicile
1000~ 3162-
~ 316" .~.
100
90
80
70
60 50 40 % of answers
30
20
10
Figure 17 Time to transport food to home and place it in refrigerator Figure 17 Temps nbcessaire pour revenir au domicile et mettre les produits achetbs dans le rbfrigbrateur
range in times to bring food home was extremely large: from two minutes for a piece of fish to just over two days for a piece of cheese transported from the continent (Figures 16 and 17).
Storage life of refrigerated foods Stated storage life of food versus shelf life. The remaining shelf lives of fats, fish and meats were noted from the food packaging and compared with the estimated consumption time stated by the householder. A number of participants could not estimate when they would consume certain foods and these data were excluded from the analysis. The data were examined as the number of days storage
0
Consumer handling of chilled foods: J. Evans Under-estimate of storage,f i ~
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Over-estimateof .~e life
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-1500 -1250 -1000 -750 -500 -250 250 Numberof days storageliferemaining
500
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Figure 18 Remaining storage life of food in householders' refrigerators Figure 18 Nombre de jours restant avant la date limite, pour les ali-
|
|
I
10 12 % of answers
4
|
!
14
16
18
20
Figure 19 Number of days of storage life remaining at estimated date of consumption Figure 19 Nombre de jours durant lesquels les denrbes seront encore consommables, apr~s la date limite fixbe
ments se trouvant dans les rdfrigbrateurs mknagers
life remaining at the estimated time of consumption. The majority of items were intended to be eaten before, or on the day the shelf life expired, with more than 50% of items having at least 17 days remaining shelf life at the time of consumption (all data to right of line in Figure
18). A number of products (17.1%) were already over their shelf life at the time of examination (all data to left of line in Figure 18). One product (from the fat category) was four years over its shelf life, but the householder stated that it would not be consumed. Another product (again from the fat category) had an estimated consumption date one year ahead (197 days over its shelf life) (Figure
x=y
30
25 20 •
•
~o
19). Stated storage life of food versus storage period stated in questionnaire. Each participant's perceived storage life for meat, fish or fat items in the questionnaire was plotted against actual storage times of foods in individual participant's refrigerators. ANOVA demonstrated significant differences (P < 0.001) in actual and perceived storage times for different foods. Actual storage times were generally greater than storage times stated in the questionnaire, with 66.9% of samples being kept for longer periods (Figure 20). Mean storage times were greater than the perceived storage time for all meat, fish and fat items except pies, which were thought to have an acceptable storage life of 3.3 days and were stored for 3.2 days (Table 1). Conclusions Most householders shopped at least once per week at a shop within five miles of their home. Large and small quantities of chilled food (defined as greater or less than a carrier bag of food) were generally bought at least once per week by the majority of households. Large amounts of food were usually transported home by car, whereas small amounts were usually brought home on foot.
0
5
10 ~t~
15
20
25
30
storage We ( ~ )
Figure 20 Perceived versus actual storage life Figure 20 Dur~e de conservation dans l'esprit des consommateurs par rapport ?l la durbe de conservation rblle
Table 1 Mean, actual and perceived storage life Tableau 1 Durbe de conservation moyenne rkelle et durke de conservation moyenne dans l'esprit des consommateurs
Food Bacon Cooked meat Cooked poultry Cottage cheese Fish Pate Pies Raw meat Raw poultry Sausages
Actual mean storage life (days)
Perceived mean storage life (days)
8.2 5.4 3.9 6.9 3.7 10.3 3.2 3.9 3.3 5.6
6.6 4.5 2.4 4.9 2.0 4.1 3.3 2.4 2.5 4.1
Rev. Int. Froid 1992 Vol 15 No 5
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Consumer handling of chilled foods: J. Evans During the journey home the majority of householders were never delayed and required less than half an hour to reach home. Most did not use a protective bag or box to keep food cool during the journey home. The majority of chilled food was purchased from a supermarket with substantial percentages of some particular foods being purchased from other sources. The majority of householders thought that most chilled foods should be stored for two days or less. Exceptions were chilled fish, with a storage time of one day or less, and eggs and bacon, which most people were happy to keep for a week. However, a number of householders stored certain foods for much longer periods. Approximately half the householders expressed a degree of concern about food poisoning and considered meat and poultry to be the main problems. However, worries about these foods had not prevented many households from buying the products. The knowledge of food poisoning bacteria was relatively low with only
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Int. J. Refrig. 1992 Vo115 No 5
Salmonella and Listeria being named by over half the participants.
Acknowledgements The author would like to thank the Ministry of Agriculture Fisheries and Food for providing funding for this investigation and Mr S. James, Mr I. Stanton and Mr S. Russell for their valued assistance during the investigations.
References 1 2
Meffert, H. F. Th. Economic developments pertinent to chilled foods In Chilled Foods - The State of the Art (Ed T. R. Gormley) Elsevier Science Publishers (1990) Evans, J. A., Stanton, J. I., Russell, S. L., James, S. J. Consumer Handling of Chilled Foods: A Survey of Time and Temperature Conditions MAFF Publications, London, UK (1991)
A survey has been made of 252 households in the UK to evaluate consumer handling of chilled foods. The survey has provided information on the shopping habits of the households in terms of the types of shops they use, their shopping frequency and transportation arrangements. Data are also presented on the consumer's attitude to and knowledge of food safety and storage times. By using data obtained from a study of the chilled products present in the householders' refrigerators, a comparison has been made between the consumer's expectations in terms of storage life and their practice. (Keywords: chilled foods; consumer storage; domestic refrigerators)
Manipulation des produits r&rig6r6s par les consommateurs: Perception et pratiques On a effectub une enqu~te auprOs de 252 mbnages au Royaume Uni, sur la fagon dont ils manipulent les produits rbfrigbrbs. Des informations ont btb obtenues sur les habitudes des consommateurs lorsqu'ils font leurs courses, et plus prbcisbment sur le type de magasins auxquels ils se rendent, sur la fr~quence de leurs achats et sur les moyens de transport qu 'ils utilisent. Des donnbes sont bgalement fournies sur l'attitude du consommateur et sur sa connaissance de l'innocuitb et de la durbe de conservation des aliments. En utilisant les donnbes obtenues lots d'une btude sur les produits rbfrigkrbs trouvbs dans les rkfrigbrateurs des mbnages, on a comparb les diverses attentes des consommateurs en termes de dur~e de conservation, ainsi que leurs habitudes respectives.
(Mots cl+s: produit r&rig6r6; entreposage du produit chez le consommateur; r6frig6rateur domestique)
Products that require refrigeration make up 63% of the contents of the food basket of the average European ~. Only 3% of the basket's contents is sold in a frozen form, which means that chilled or flesh foods make up 60%. The terms chilled and flesh encompass a wide range of foods with optimum storage temperatures from - I * C for flesh fish to approaching 18°C for certain exotic fruits. In the past few years there has been considerable publicity surrounding cases of food poisoning associated with the consumption of certain chilled foods. This has ranged from S a l m o n e l l a in eggs and poultry products to Listeria m o n o c y t o g e n e s in ready meals, prepared salads and mould- or bacteria-ripened soft cheese. The importance of maintaining strict hygiene and temperature standards during the production, storage and retailing of chilled foods was highlighted in the U K by the introduction of the Food Hygiene (Amendment) Regulations 1990. However, the requirement for good temperature control and handling procedures does not stop when the food leaves the retail store. The treatment of the chilled food by the consumer and their overall attitude to the product is an important final step in the cold chain. Since little data could be found on the consumer handling of chilled food in the UK, the Ministry of Agriculture Fisheries and Food (MAFF) funded a consumer survey. The full study 2 has just been published and this paper gives details of some of the data obtained on consumer perceptions and practice. A second paper in this journal will provide data from the study of the temperature of foods in domestic handling. The survey population consisted of 252 households selected from the towns of Weston-super-Mare, Bridgwater and Taunton 0140-7007/92/0502904)9 © 1992 Butterworth-Heinemann Ltd and IIR
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Int. J. Refrig. 1992 Vo115 No 5
in the south-west of England. The survey was divided into two parts: the first between September and December 1989 and the second between February and May 1990. The aim was to reflect varying seasonal ambient weather conditions. Each part of the survey consisted of a different group of 126 households split evenly between the three towns. The three towns of Weston-super-Mare, Bridgwater and Taunton were selected because of their varying demographic and social status. Weston-super-Mare is a predominantly better-off retirement area with high-status non-family areas, affluent suburban housing and older housing of intermediate status. Bridgwater consists mainly of council estates and older housing of intermediate status. Taunton has a variety of older housing, council estates and high-status non-family areas, affluent suburban housing and better-off retirement areas. Participants were selected by CACI Market Analysis Division (a commercial market research company) as a one in n sample from the electoral registers covering the three towns, with the aim of producing a representative range of social and economic groups within each town. In the initial part of the survey questions dealt with shopping habits for chilled food, including details such as the frequency of shopping, distances travelled, time taken and the shops that were used. Participants were also asked about the length of time they would expect to be able to store various categories of chilled food after purchase and their attitude towards and knowledge of food poisoning. Participants were then asked whether a list could be made of the contents of their refrigerators with more detailed questions being asked about any meat
Consumer handling of chilled foods: J. Evans (including all cooked and raw red and white meat), fish (all fresh and cooked fish) or fat (cheese, dairy and vegetable fats) items present. Questionnaire responses were divided into part of survey (1 or 2) and town (Weston-super-Mare, Bridgwater or Taunton) and tested to determine whether answers were consistent throughout the survey. Owing to the unbalanced nature of the questions, responses required stabilizing by means of a variance stabilizing (arcsin) transformation to produce the transformed data x where:
0.79% 15.48% 26.19%
J
< onceJweek OncMweek
Twiee/wcek 3-4 times/week [ ] 5-7 times/week
23.81%
x = (-!0--00)arcsin {( % p°pulati°nlwtlO0 ] J Stabilized questionnaire data were examined by analysis of variance (ANOVA) to determine whether statistical differences existed between question responses in part and town. If differences between part and town were not significant, answers were combined and considered together.
33.73% Figure 1 Number of shopping trips per week Figure 1 Nombre de dbplacements par semaine pour faire des courses
Questionnaire data
Household shopping patterns The initial questions to participants were designed to provide an easy introduction to the survey and dealt with people's general shopping patterns. Initially participants were asked how often each week they visited the shops for food. This question was asked to determine the total number of days the household (inclusive of all members) shopped for chilled food per week. If the household shopped at irregular intervals, they were asked to state the average number of days per week they would usually visit the shops. Responses included both shopping trips for small quantities of food, such as bread or milk, and also larger weekly food purchases. ANOVA revealed differences between answers (P < 0.01), but no variations between part of survey or town. Therefore, question answers from both parts and towns could be combined and considered together. With two exceptions all the households (99.2% of the survey population) shopped on at least one day per week for chilled food. The greatest number of respondents (33.7%) shopped for food three to four days per week, closely followed by 26.2% who shopped five to seven days per week and 23.8% who shopped on two days. Few households (16.3%) shopped for food less than twice per week
(Figure 1). Participants were next asked to state on which day or days they did their shopping. The amount of shopping was divided into larger amounts, defined as the purchase of a carrier bag or more of food, and smaller quantities, defined as less than a carrier bag of food. ANOVA demonstrated significant differences in answers (P > 0.05), but no differences between part or town (P > 0.05). Larger quantities of food were bought by 97.7% of the householders interviewed: 73.8% of these shopped once per week and 23.0% visited the shops twice or more per week. A small proportion (0.8%) shopped at intervals of greater than once per week, most usually monthly or every two weeks. The remaining 2.3% of households stated that they never bought large quantities of food. Larger quantities of food were most often bought on Thursday, Friday or Saturday, with Friday being the most popular day (Figure 2).
"~ZgYm
Variable
Sunday Saturday Friday
I~i~,~'...... i,.'............... . "...<~!1 l
~
Thursday N
~
~
~
.
~
I
I
[] Small
Wednesday Tuesday Monday I
0
'
I
I0
'
I
20
"
I
30
"
I
40
"
I
50
"
I
60
*
I
70
'
I
80
"
I
90
"
I
"
I
I00110
Number of occurrences Figure 2 Figure 2
Day of week on which shopping was done Jour de la semaine durant lequel les courses sont effectubes
Most households shopped for small quantities of food on a variable basis, as required. Only 15.5% of households stated that they never bought small amounts of food, whereas most people visited shops for small amounts once per week (Figure 2). Questions were also asked to determine the types of shopping outlets most commonly visited when buying food. If participants shopped at more than one outlet for a particular food type, they were asked to state which type of shop they used most regularly, and the one they used as a second choice. It was clearly stated that this question only encompassed chilled foods and did not include frozen foods. Participants were not prompted in their replies and usually responded to the question by stating specific shops that they visited, which were then placed within the relevant category. ANOVA of participants' first and second choice shop types in part and town revealed statistical differences (P < 0.001) between shops where food was bought and differences (P < 0.001) between first and second choice answers. Variations between towns or parts were not significant. Rev. Int. Froid 1992 Vol 15 No 5
2.91
Consumer handling of chilled foods." J. Evans 3.57% 9.52% i [] [] []
I day ago 2 days ago 3-4 days ago 5-6 days ago More than 7 days
> 5 miles
I
> 1, up to 5 miles
19.84%
I~1 Small
51.59% > half,up to 1 mile
Up to halfa mile ID.~070
0
20
40
60
g0
100
120
140
Numberof occurrences Figure 3 Figure 3
Length of time since last shopping trip
Temps qui s'est kcoulb depuis les derniers achats
As a first choice over 40% of participants preferred to buv meat, meat products, fish, eggs, dairy and dessert products in a supermarket. Salad items were preferably bought in a small grocer or local shop. A number of people also bought meat and fish in specialist shops such as butchers or fishmongers and eggs from a farm. As a second choice most participants shopped in either a supermarket, a small grocers or a specialist shop. A maximum of 14.3% of interviewees bought food in more than one type of shop, probably reflecting the easy availability of first choice shops in the towns surveyed. Over half (51.6%) of the householders interviewed had shopped for food on the day of or the day before the survey. Few households (3.6%) had not shopped within the last seven days, reflecting the trend for shopping once or more per week. Statistical differences in answers were found (P < 0.001), but differences between part or town were not significant (Figure 3). To obtain a general picture of shopping habits participants were then asked a series of questions about the distance they travelled to buy chilled food and the method of transport used. Participants who bought food in several locations or used varied methods of transport could answer within more than one category. ANOVA demonstrated significant differences (P < 0.05) between answers, but not between part or town. Most participants in the survey did their main shopping between one and five miles from their homes. Only one of the householders (0.4%) bought food from shops within more than one of the distance categories. Few householders travelled more than five miles to shop. Of the 246 households who shopped for large amounts of food, 85.3% always or occasionally used a car to transport their main shopping home. Only eight people (3.2%) used more than one form of transport to bring larger amounts of shopping home (Figures 4 and 5). In all three towns surveyed there was at least one large supermarket within one to two miles of the town centre. Travelling distances would probably have been greater if rural areas had been included in the survey. Small quantities of food were generally bought close to the home, again reflecting the availability of shops in the towns surveyed. A small proportion (5.2%) of householders shopped within two of the distance categories. Most householders (87.6%) who bought small quantities of food transported it home by either foot or car. Forty292
Int. J. Refrig. 1992 Vo115 No 5
Figure 4 Figure 4
Distance to shops
Distance s~parant les consommateurs des magasins
Motorbike
Cycle
U I~-ge [] Sman Taxi
Foot
0
20
40
60
80
100 120 140 160
180 200 220
Number of o c c ~
Figure 5 Figure 5
Mode of transport used
Mode de transport utilisb
six people in this category (21.6%) used more than one mode of transport to bring food home (Figures 4 and 5). The time required for participants to transport chilled food home from the shops was also investigated. Significant differences (P < 0.001) were found between all question answers, but differences between part or town were not apparent. If delays due to visits to friends, relations or work patterns were not taken into account, the vast majority (96.3%) of households who did a main shop said that they reached home within half an hour of leaving the shop. This again reflected the availability of suitable shopping within easy travelling distance in the towns surveyed. No households required more than two hours to bring food home. Small quantities of food were generally brought home within half an hour of purchase. However, a small proportion of food required more than two hours to be brought home and this was generally due to householders shopping further afield because of work or social commitments (Figure 6). Delays in bringing food home were rare (Figure 7). Most households (68.7%) always brought food straight home from the shops. Only 1.2% of households were
Consumer handling of chilled foods: J. Evans 1.19% > 4 hours
to 4
I
[] [] []
hours
Cool box Cool bag None
[] Large
to 2 hours
Small Italf to 1 hour
I:.
20
.....................
40
60
80
100 120 140 160 180 200 220 240
87.30%
Number of occurrences
Figure 6 T i m e to b r i n g f o o d h o m e f r o m s h o p s F i g u r e 6 Temps nbcessaire pour emporter les achats, du magas& au domicile
1.19% 6,32%
~! Always [ ] Very Frequently [ ] Sometimes
[] Rarely [] Nev~ 9.49%
Figure 7
Frequency of delays
Figure 7
Fr~quence des retards
always delayed, and 6.3 % very frequently delayed, whilst transporting food home. It must be stressed that some participants who delayed bringing food home stored perishable foods in a refrigerator during the delay period. During the journey home the vast majority (87.3%) of people did not use any means of protecting food from temperature gains during transportation. Only 12.7% of participants stated that they used either a cool bag or box to transport some of their food home (Figure 8). The reason for such a low utilization of protective bags or boxes could be due to short journeys (less than half an hour) home. However, the small number of people who required between one and four hours to transport food home did not always use protective boxes or bags. These people could be unaware of the potential problems of transporting food home in high ambient temperatures.
Storage and food safety in the home After determining the way in which chilled products were bought and how they were transported, participants
Figure 8
Use of cool bags/boxes
Figure 8
Utilisation de sacs ou de boites isothermes
were asked a series of questions about food storage and food safety in the home. Participants were first asked to estimate the storage life of a range of popular chilled food items. It was stressed that the foods were all chilled and not frozen and that the foods were initially of good quality and were of the type generally bought by the householders. If participants were unsure of an answer they were given a chance of stating that they did not have an opinion. ANOVA of all answers revealed no statistical differences (P > 0.05) between parts or towns. However, significant variations (P < 0.001) in actual answers were found, indicating that individual opinions on the refrigerated storage life of the chilled foods were variable. Most foods (prepared meals, pizza/quiche, cold pies, pate, sausages, raw poultry, cooked poultry, cooked meat and raw meat) were thought to store well for two days. However, a number of people considered that these foods could be stored for longer than seven days and sometimes as long as 30 days. Most participants thought that bacon, eggs, cottage cheese and salad could be stored for up to a week, although a few people considered that storage of up to 30 days was acceptable. Fresh fish was generally considered to store least well, with most participants stating that they would only store fish for one day or less. Most participants were prepared to give an opinion on the storage life of the chilled foods considered, although a small percentage (at most 7.5%) stated that they did not have an opinion or did not know the answer. The range in anticipated storage life for different food types varied considerably. Opinions on the storage lives of individual foods ranged from half a day to seven days (range six and a half days) for cold pies and sausages to between half a day and 30 days (range 29.5 days) for pate, bacon and cottage cheese. The minimum storage life for all foods except eggs (minimum storage life of two days) was either a quarter or half a day. The modal storage life ranged from one to seven days with 10 out of the 15 foods having a modal storage life of two days. A small number of householders thought that they could store chilled foods for periods of up to 30 days. Bacon, cottage cheese, eggs and pate were all thought to be
Rev. Int. Froid 1992 Vo115 No 5
293
Consumer handling of chilled foods: J. Evans
Minimum Eggs Sausages ~
Salad
Eggs
Salad ~ !
Raw poultry Raw meat Pizza Pate Cooked poultry
~x:~i~%%
Cottage cheese ~ ~ i ! : :
~8i ~ ~:: ~:: ~-~i
Bacon Sausages Raw poultry Raw meat Prepared meal
Cooked meat
~@,~-*.'~!~,~ !::iii~iiii~il i!~!~i~i i!i!i~iiii~ i~::i
Pizza
Cottage cheese ~ i
...L.
Pate Cooked poultry Cooked meat Cold pies Burger Fish
Cold pies Bacon Prepared meal
~i ~!i ~ Fish ~ Burgeas ~ 0.0
0.5
1.0 1.5 Days
Maximum
Mode
2.0
Ill
"
Bacon Salad Cooked poultry Cooked meat Raw meat
I
i!~'.:it ~ii ~i!ii ~ii! ~::i~i~ ~ [ 0
Pate Eggs Cottage cheese
Burger Pizza :-:..~:..~.:~.-....-..-:-:-:il "::.!:~¢i.::~""::E:7 Raw poultry i#..%-~!:~"~!'! Fish Sausages Cold pies 0
1 2 3 4 5 6 7 Days
10 20 Days
30
Figure9 Minimum,modal and maximum storage lives stated by householders Figure 9 Durbes de conservation minimale, modale et maximale, avancdes par les consommateurs acceptable after this period by a small proportion of participants. Cooked meat and poultry were also thought to store for up to 21 days by a few householders
14.68%
(Figure 9).
Participants were next asked a series of questions to gauge their concern and knowledge of food poisoning. The degree of concern about food poisoning was assessed on a five-point scale ranging from very concerned to not at all concerned. Answers were restricted to concern about food from shops and did not include concern about food poisoning due to restaurant or fastfood-type meals or food. If replies from participants did not directly fall into one of the five categories further questions were asked to assess the individual's degree of concern about food poisoning. The answers people provided were statistically different (P < 0.001), but did not vary between parts or towns (P > 0.05). The greatest number of participants (56.7%) were either only slightly concerned or not at all concerned about food poisoning. However, 31.7% of participants admitted to being concerned or very concerned about food poisoning (Figure 10). All participants were asked to name foods that they considered might constitute a food poisoning risk. Individuals could name as many foods as they wished. Significant differences (P < 0.001) were found between the types of food named as presenting potential food poisoning problems, but these did not vary in parts or towns in the survey. Most of the respondents (73%) considered poultry to be a problem. Raw poultry was considered to be a greater risk than cooked poultry. Meat was also considered likely to cause food poisoning, with 66.7% of participants mentioning either raw or cooked meat as a potential problem. It was interesting to note that although poultry and meat were considered a likely cause of food poisoning, participants did not necessarily consider that these foods had short storage lives. It is 294
Int. J. Refrig. 1992 Vo115 No 5
[]
Vczyconcerned
[]
~
[ ] ~
y
coacea~
[ ] Slightly co~aeerned [ ] Not at all concerned 40.87% 17.06%
15.87%
Figure 10 Concern about food poisoning Figure 10 Preoccupation par rapport aux intoxications alimentaires therefore possible that people did not associate storage time as being related to any food poisoning problem. Foods such as eggs, yogurt and cook-chill meals, on which media attention had recently focused, were not mentioned as much as might have been expected. These foods were only mentioned by a maximum of 16.7% of participants, perhaps demonstrating the transient nature of food scares (Figure 11). Participants were asked to name as many germs/bacteria as possible. Answers were never prompted and only the clear name of a bacterium accepted. Statistical analysis of the answers revealed differences (P < 0.001) between the numbers of bacteria that participants could name. Differences between parts and towns were not significant (P > 0.05). Most householders (61.1%) could name two or more bacteria, the most common being Salmonella and Listeria. Only a small number of partici-
Consumer handling of chilled foods: J. Evans Poultry-raw Meat~ Poultry-eo~ed Meat-raw Pate Eggs Fish Cook-chill foods
Cryptosporidium Enterococcus Campylobacter Clostridium Streptococci
Cheese
Pies Dairyp~ucts Sausages
E. Coli Staphylococci
Sd~k Yogurt Sandwiches Fruit Bacon Leftovers Jelly l r ~ i ~ t ~ food
Listeria Salmonella
it~
.
. ,
-
10
33 43 5;
70 8;
Figure 13 Figure 13
Number of
20
|
-
30
,
-
40
i 50
o
|
_
-
60
, 70
-
80
Bacteria named by participants Bact#ies cit&s par les participants
.............. Eggs
0 1
Yog,ul
Ch=se ~..cod=d Pies Coldr~t R ~ mest Cook-chillf~ds B=on Sausages
0.40%
•2 []3 1"-i4
Fish
i5 []
"
Foods considered a risk Aliments consid#bs "'~ risques"
Number of bacteria named
[] []
|
% of surveypaticipanlswho could namebacteria
o l; Figure 11 Figure 11
m
Botulinum
DelryIxed=ts
6
~l
Pate
~
Cheese ~ , ~ a Poultry-ceoked ' ,~mm~ Dairyproducts ' im m Eggs Coldmeat ~ R | [] | Part 1 Red meat ] Part 2 | Pies' Fish | C o o k - c h i l l foods | Bacon 13 I; 2() ~ 33 Numberof cccmrerr.es Numberof occurrences m
-
-
-
~
33
Figure 14 Foods that participants had stopped buying due to concern about food poisoning Figure 14 Aliments que les participants ont cessb d'acheter par crainte
d'intoxication alimentaire
9%
Figure 12 Number of bacteria named Figure 12 Nombre de bact#ies cit&s
pants (2.4%) could name four or more bacteria and 13.1% of the survey population could not name any
(Figure 12). The best known bacteria were Salmonella (which 78.9% of those surveyed could name), Listeria (61.5%) and Botulinum (16.2%). These bacteria were probably familiar due to media coverage at the time of the survey, which dealt with food safety issues. Few other bacteria could be named by participants in the survey (Figure 13). Participants were asked whether they had stopped buying any foods due to concern about food poisoning. Only answers that directly related to worries about food poisoning were included. Participants were not limited in the number of foods they could name and the answers were never prompted. ANOVA revealed significant differences (P < 0.001) between the numbers of people who had stopped buying
the foods mentioned. The numbers of people who had stopped buying the foods were not significantly different (P > 0.05) in the three towns surveyed. There was, however, a significant (P < 0.05) interaction between food type and part, which was due to differences in ranking of foods in parts 1 and 2. The greatest number of participants (69%) stated that they had not stopped buying any foods due to worries about food poisoning. In part 1 of the survey a greater number of people were worried about buying cheese, eggs, pate and yogurt; all foods on which the media had recently focused. In part 2 the number of people who stated that they no longer bought these products was greatly reduced, except in the case of cheese, which was still considered a potential health risk by 7.9% of those surveyed (Figure 14).
Chilled food storage in domestic refrigerators Two hundred and forty-eight (98.4%) households agreed to list the contents of their refrigerators. Questions were asked to determine, for the individual fish, fat and meat items present, the purchase date and consumption date, the time taken to bring the item home and place it in a refrigerator and the method of transport. If the food was packaged, the best-before or eat-by date was also noted. The data were analysed to determine:
Rev. Int. Froid 1992 Vo115 No 5
295
Consumer handling of chilled foods: J. Evans 10000
Other
3162"
Taxi
O
g~ , "~ 316, g .
Cycle
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~
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~ 100'~ E 32.~ • .~ 103
~
.
.
.
.
.
.
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.
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::::::::::::::::::::::::::::::::: ::::::::::::::::::::::::::::::::
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% of occutrerr,,~ 0
Figure 15 Transport used to bring meat, fish or fats home
-
100
,
90
80
70
Figure 15 Mode de transport utilisk pour rapporter la viande, le poisson ou les aliments ~ teneur en graisse jusqu'au domicile
1. the method used to transport food home; 2. the time required to bring food home and to place it in a refrigerator; 3. storage life of refrigerated foods. The third category was subdivided into (a) stated storage life of food versus shelf life and (b) stated storage life of food versus storage period stated in questionnaire.
The method used to transport food home The method used to transport home the fat, fish and meat items stored in each householder's refrigerator was noted. A number of householders could not remember the exact way in which they had bought items home and therefore not all fat, fish or meat items stored in refrigerators were included. A N O V A demonstrated that significant differences (P < 0.001) existed between modes of transport, but not between part or town. By far the greatest number of householders transported fat, fish or meat items home by car (77.2%). The second most popular method of transport was by foot, which accounted for 13.2% of items examined. Few items (less than 4% in each case) were transported by bus, train, bicycle, taxi or other methods (Figure 15).
The time required to bring food home and to place it in a refrigerator The time required to bring fat, fish or meat items home from the shops and the time required to place the food items in the refrigerator were analysed. A number of participants could not remember times required to bring certain foods home and therefore not all foods itemized were included. No differences were found between food types or times required to bring food types home in either part or town (P > 0.05). The overall mean time required to bring food home was 36.4 minutes with a standard deviation of 13.3 minutes. This extended to 42.8 minutes with a standard deviation of 18.7 minutes by the time the food had been placed in a refrigerator. The greatest number of items were transported home within 10 minutes and were placed in a refrigerator within 13 minutes. However, the
296
Int. J. Refrig. 1992 Vo115 No 5
60 50 40 % of answers
30
20
10
0
Figure 16 Time to transport food to home Figure 16 Temps nbcessaire pour revenir au domicile
1000~ 3162-
~ 316" .~.
100
90
80
70
60 50 40 % of answers
30
20
10
Figure 17 Time to transport food to home and place it in refrigerator Figure 17 Temps nbcessaire pour revenir au domicile et mettre les produits achetbs dans le rbfrigbrateur
range in times to bring food home was extremely large: from two minutes for a piece of fish to just over two days for a piece of cheese transported from the continent (Figures 16 and 17).
Storage life of refrigerated foods Stated storage life of food versus shelf life. The remaining shelf lives of fats, fish and meats were noted from the food packaging and compared with the estimated consumption time stated by the householder. A number of participants could not estimate when they would consume certain foods and these data were excluded from the analysis. The data were examined as the number of days storage
0
Consumer handling of chilled foods: J. Evans Under-estimate of storage,f i ~
3162.3
Over-estimateof .~e life
250.0
1000.0
99.0
8 38.8
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o
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~. ~
~= 14.8
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1.5 0
=
=
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,
-1500 -1250 -1000 -750 -500 -250 250 Numberof days storageliferemaining
500
750
Figure 18 Remaining storage life of food in householders' refrigerators Figure 18 Nombre de jours restant avant la date limite, pour les ali-
|
|
I
10 12 % of answers
4
|
!
14
16
18
20
Figure 19 Number of days of storage life remaining at estimated date of consumption Figure 19 Nombre de jours durant lesquels les denrbes seront encore consommables, apr~s la date limite fixbe
ments se trouvant dans les rdfrigbrateurs mknagers
life remaining at the estimated time of consumption. The majority of items were intended to be eaten before, or on the day the shelf life expired, with more than 50% of items having at least 17 days remaining shelf life at the time of consumption (all data to right of line in Figure
18). A number of products (17.1%) were already over their shelf life at the time of examination (all data to left of line in Figure 18). One product (from the fat category) was four years over its shelf life, but the householder stated that it would not be consumed. Another product (again from the fat category) had an estimated consumption date one year ahead (197 days over its shelf life) (Figure
x=y
30
25 20 •
•
~o
19). Stated storage life of food versus storage period stated in questionnaire. Each participant's perceived storage life for meat, fish or fat items in the questionnaire was plotted against actual storage times of foods in individual participant's refrigerators. ANOVA demonstrated significant differences (P < 0.001) in actual and perceived storage times for different foods. Actual storage times were generally greater than storage times stated in the questionnaire, with 66.9% of samples being kept for longer periods (Figure 20). Mean storage times were greater than the perceived storage time for all meat, fish and fat items except pies, which were thought to have an acceptable storage life of 3.3 days and were stored for 3.2 days (Table 1). Conclusions Most householders shopped at least once per week at a shop within five miles of their home. Large and small quantities of chilled food (defined as greater or less than a carrier bag of food) were generally bought at least once per week by the majority of households. Large amounts of food were usually transported home by car, whereas small amounts were usually brought home on foot.
0
5
10 ~t~
15
20
25
30
storage We ( ~ )
Figure 20 Perceived versus actual storage life Figure 20 Dur~e de conservation dans l'esprit des consommateurs par rapport ?l la durbe de conservation rblle
Table 1 Mean, actual and perceived storage life Tableau 1 Durbe de conservation moyenne rkelle et durke de conservation moyenne dans l'esprit des consommateurs
Food Bacon Cooked meat Cooked poultry Cottage cheese Fish Pate Pies Raw meat Raw poultry Sausages
Actual mean storage life (days)
Perceived mean storage life (days)
8.2 5.4 3.9 6.9 3.7 10.3 3.2 3.9 3.3 5.6
6.6 4.5 2.4 4.9 2.0 4.1 3.3 2.4 2.5 4.1
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Consumer handling of chilled foods: J. Evans During the journey home the majority of householders were never delayed and required less than half an hour to reach home. Most did not use a protective bag or box to keep food cool during the journey home. The majority of chilled food was purchased from a supermarket with substantial percentages of some particular foods being purchased from other sources. The majority of householders thought that most chilled foods should be stored for two days or less. Exceptions were chilled fish, with a storage time of one day or less, and eggs and bacon, which most people were happy to keep for a week. However, a number of householders stored certain foods for much longer periods. Approximately half the householders expressed a degree of concern about food poisoning and considered meat and poultry to be the main problems. However, worries about these foods had not prevented many households from buying the products. The knowledge of food poisoning bacteria was relatively low with only
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Salmonella and Listeria being named by over half the participants.
Acknowledgements The author would like to thank the Ministry of Agriculture Fisheries and Food for providing funding for this investigation and Mr S. James, Mr I. Stanton and Mr S. Russell for their valued assistance during the investigations.
References 1 2
Meffert, H. F. Th. Economic developments pertinent to chilled foods In Chilled Foods - The State of the Art (Ed T. R. Gormley) Elsevier Science Publishers (1990) Evans, J. A., Stanton, J. I., Russell, S. L., James, S. J. Consumer Handling of Chilled Foods: A Survey of Time and Temperature Conditions MAFF Publications, London, UK (1991)