Fresh, frozen, or ambient food equivalents and their impact on food waste generation in Dutch households

Highlights

• Food waste index calculated to make relative comparisons of amounts of food waste.

• Differences in food preservation method impacted on food waste generation.

• Usage of frozen food equivalents was associated with lower waste generation.

• Encouraging consumers to use frozen foods more often might reduce food waste.

Abstract

In Europe, it is estimated that more than 50% of total food waste – of which most is avoidable – is generated at household level. Little attention has been paid to the impact on food waste generation of consuming food products that differ in their method of food preservation. This exploratory study surveyed product-specific possible impacts of different methods of food preservation on food waste generation in Dutch households. To this end, a food waste index was calculated to enable relative comparisons of the amounts of food waste from the same type of foods with different preservation methods on an annual basis. The results show that, for the majority of frozen food equivalents, smaller amounts were wasted compared to their fresh or ambient equivalents. The waste index (WI) proposed in the current paper confirms the hypothesis that it may be possible to reduce the amount of food waste at household level by encouraging Dutch consumers to use (certain) foods more frequently in a frozen form (instead of fresh or ambient). However, before this approach can be scaled to population level, a more detailed understanding of the underlying behavioural causes with regard to food provisioning and handling and possible interactions is required.

Introduction

About 25% of all food supplied for human consumption is lost or wasted during various phases in the food supply chain (Stancu et al., 2016, Secondi et al., 2015, Kummu et al., 2012). In Europe, it is estimated that more than 50% of total food waste is generated at household level (Stenmarck et al., 2016, Stancu et al., 2016, Secondi et al., 2015, Beretta et al., 2013, Kummu et al., 2012, Gustavsson et al., 2011, Parfitt et al., 2010). Most of this waste is avoidable, as at some point prior to its disposal the food was edible (Quested et al., 2013a, Parfitt et al., 2010). Food waste reduction and prevention are important strategies to increase the availability of food throughout the supply chain in order to feed the global population and to achieve necessary environmental impact savings (Stancu et al., 2016, Secondi et al., 2015).

Studies focused primarily on estimating the amount and general composition of food waste at household level (e.g. Katajajuuri et al., 2014, Silvennoinen et al., 2014, Gutiérrez- Barba and Ortega-Rubio, 2013, Griffin et al., 2009, Van Westerhoven, 2010, Van Westerhoven, 2013), irrespective of method of preparation, method of preservation, or way of storage. As a result, there is limited understanding of the various underlying causes with regard to consumers’ food waste behaviour (Stancu et al., 2016, Abeliotis et al., 2015, Secondi et al., 2015, Stefan et al., 2013, Gustavsson et al., 2011). Attention is paid to attitudes, habits, and motivations, and to socio-economic characteristics associated with individual consumers’ behaviour towards food waste generation. In several studies it has been shown that consumers’ planning and shopping routines – determined mostly by their moral attitudes and perceived behavioural control – are important predictors of their food waste generation, i.e. consumers that make a shopping list, plan their meals, and check their food inventories report less food waste than those who report more frequently buying too much food or making unintended food purchases (Stancu et al., 2016, Porpino et al., 2015, Quested and Luzecka, 2014, Stefan et al., 2013, Quested et al., 2013b, Quested et al., 2011). In addition, in a Canadian sample (Parizeau et al., 2015) it was found that households that spend routinely more money per capita on groceries produced more organic waste, even though they differ in their food-related attitudes and behaviours. Aschemann-Witzel et al.’s (2015) review paper points to consumers’ lack of sufficient motivation, ability, and opportunity to reduce food waste, including lack of knowledge and planning, as important factors causing food waste generation. Systematic storage practices in the refrigerator might therefore be useful to reduce food waste (Farr-Wharton et al., 2012, Farr-Wharton et al., 2014). Household size was found to be another factor in food waste generation, with smaller households contributing less than larger households to net food waste, whereas at the same time persons living alone were found to produce the highest amounts of waste per person (Koivupuro et al., 2012).

Surprisingly little attention has been paid so far to product-related characteristics and/or attributes that might drive consumers’ food waste generation. A study on packaging attributes in relation to household food waste generation reported that too large volumes, packages that are difficult to empty, and packages that have passed the best before date were associated with higher amounts of food waste (Williams et al., 2012). Similarly, based on a supplier–retailer interface assessment, it was suggested that frozen foods were associated with lower levels of food waste, and similar cases were found for some ambient food products. These waste-reducing outcomes were attributed mainly to the extended shelf-life of ambient and frozen foods (Mena et al., 2011). The current recommendation from the Waste & Resources Action Programme (WRAP) research to use the freezer to extend the shelf-life of foods in order to decrease food waste levels is in line with this supply chain-based observation (Quested and Luzecka, 2014, Quested et al., 2013a). On should realise however, whether benefits of reduced waste exceed increased energy costs of maintaining reduced storage temperature, as recently studied by Eriksson et al. (2016) for Swedish supermarkets.

Actual consumer data at household level to support this notion of WRAP are currently scarce. On the basis mainly of food waste data over a relatively short period of time (i.e. a week), Martindale (2014) suggests that food wastage at home was significantly lower for frozen food products compared to their fresh equivalents. However, in this study, neither the actual amounts of the specific foods wasted nor their consumption frequencies were reported. Thus, a relative comparison between fresh, frozen, and ambient food equivalents – taking consumption frequency, disposal frequency, and amounts of food usually wasted into account over a longer period of time (i.e. a year) – is needed to further our understanding.

The aim of the current study is to explore possible impacts of different preservation methods on food waste generation in Dutch households taking both concurrency of frequency and habitual amounts into account. An extended survey on self-reported food waste is performed in a Dutch consumer sample. In addition to general information gathered with regard to Dutch household’s routines and general food waste generation, product-specific information is collected for food equivalents with different methods of preservation at the point of sale, namely, fresh, frozen, and/or ambient. It is hypothesized that the use of frozen foods is associated with lower food waste generation in Dutch households than the use of fresh and/or ambient food equivalents.