Shelf-life determination and challenge testing 265 transportation, retailing and handling in the home have been performed, some of which have been summarised by Bogh-Soresen and Olsson(1990) Currently, the UK Food Safety Temperature Regulations (Food Safety Temperature Control) Regulations 1995 SI No 2200)allow a maximum of 8C during distribution and retail display of chilled products. It is important that this is considered when the shelf-life of products is determined, as any assessments done at lower temperatures will be affected by use of a higher temperature(see Section 10.4). 10.2.8 Consumer handling Consumer handling of chilled products can affect the quality and the safety of the product. Factors such as the time taken to carry the product home, consumer perceptions of chilled foods and domestic storage conditions need to be taken into consideration when setting up the time and temperature regime to be used in storage trials. This is perhaps the part of the chill chain that is most variable and over which the manufacturer has least influence and control. A survey of consumer handling of chilled foods in the UK(Evans 1998)indicated that most consumers shopped at least once a week for quantities of chilled foods. In the majority of cases, transport to the home was by car or foot(83%), taking an average of 43 minutes to get food from the retail store into the home refrigerator The temperature of the foods generally ranged from 4-20oC. Domestic efrigerator temperatures were found to have an overall mean temperature of 6.C with a range of -l"C to +llC On average, only 30% of refrigerators were operating below 5C. Of the refrigerators included in the survey, 7.3%were running at average temperatures of greater than 9oC, though positional temperature differences, particularly in fridge-freezers and larder freezers, indicate this figure to be higher if product is stored in the top of these refriger ators. Evans(1998)has also provided additional data on consumer practices Whilst such information gives an indication of the temperatures and times that are likely to be needed in shelf-life trials to simulate consumer handling, there is still the decision to be made with respect to what is a reasonable worst case to use. If theworst case temperatures and holding times that have been recorded were used in shelf-life tests, few of the products currently in the market-place would achieve the target shelf-life. The manufacturer has to estimate where reasonable abuse ends and unreasonable' abuse begins Consumer handling of products may not be as intended or envisaged by the manufacturer. Many chilled products are purchased on the basis of the fresh image, but then frozen at home. Opening and partial use of vacuum or modified atmosphere packaged products invalidates the shelf-life information with respect to the remaining product. A survey of consumer perceptions of the shelf-life of chilled foods has indicated that whilst consumers believe that most chilled foods should be stored for two days or less, in reality the same householders were storing certain chilled foods for considerably longer periods of time(Evans et altransportation, retailing and handling in the home have been performed, some of which have been summarised by Bøgh-Søresen and Olsson (1990). Currently, the UK Food Safety Temperature Regulations (Food Safety (Temperature Control) Regulations 1995 SI No. 2200) allow a maximum of 8ºC during distribution and retail display of chilled products. It is important that this is considered when the shelf-life of products is determined, as any assessments done at lower temperatures will be affected by use of a higher temperature (see Section 10.4). 10.2.8 Consumer handling Consumer handling of chilled products can affect the quality and the safety of the product. Factors such as the time taken to carry the product home, consumer perceptions of chilled foods and domestic storage conditions need to be taken into consideration when setting up the time and temperature regime to be used in storage trials. This is perhaps the part of the chill chain that is most variable and over which the manufacturer has least influence and control. A survey of consumer handling of chilled foods in the UK (Evans 1998) indicated that most consumers shopped at least once a week for quantities of chilled foods. In the majority of cases, transport to the home was by car or foot (83%), taking an average of 43 minutes to get food from the retail store into the home refrigerator. The temperature of the foods generally ranged from 4–20ºC. Domestic refrigerator temperatures were found to have an overall mean temperature of 6ºC with a range of
1ºC to +11ºC. On average, only 30% of refrigerators were operating below 5ºC. Of the refrigerators included in the survey, 7.3% were running at average temperatures of greater than 9ºC, though positional temperature differences, particularly in fridge-freezers and larder freezers, indicate this figure to be higher if product is stored in the top of these refriger￾ators. Evans (1998) has also provided additional data on consumer practices. Whilst such information gives an indication of the temperatures and times that are likely to be needed in shelf-life trials to simulate consumer handling, there is still the decision to be made with respect to what is a reasonable worst case to use. If the ‘worst case’ temperatures and holding times that have been recorded were used in shelf-life tests, few of the products currently in the market-place would achieve the target shelf-life. The manufacturer has to estimate where ‘reasonable’ abuse ends and ‘unreasonable’ abuse begins. Consumer handling of products may not be as intended or envisaged by the manufacturer. Many chilled products are purchased on the basis of the ‘fresh image’, but then frozen at home. Opening and partial use of vacuum or modified atmosphere packaged products invalidates the shelf-life information with respect to the remaining product. A survey of consumer perceptions of the shelf-life of chilled foods has indicated that whilst consumers believe that most chilled foods should be stored for two days or less, in reality the same householders were storing certain chilled foods for considerably longer periods of time (Evans et al. 1991). Shelf-life determination and challenge testing 265