Reducing food waste (FW) along the entire food supply chain (FSC) is an important policy priority included in the UN Sustainable Development Goals (SDGs) for 2030 [1
]. In fact, in the framework of the adoption of sustainable production and consumption models, Goal 12.3 recommends halving food losses and waste. In response to the SDGs, in 2018, the European Union encouraged the Member States to monitor and put in place actions aimed to reduce FW at every stage of the supply chain [2
According to Willett et al. [3
], reduction of food losses and waste is a key factor to increase the sustainability of the agri-food sector alongside optimization of the production processes and adoption of a healthy and sustainable diet. Food loss and waste was estimated to be one-third of the edible food as reported by the World Resource Institute [4
]. These figures are equivalent to 1.3 billion tons of food produced for human consumption wasted each year [5
] with an economic loss of €800 billion [6
]. The geographical area and level of development of countries have a differential influence on where food is wasted along with the FSC. Households and catering sectors are the most impactful (53%) in high-income regions, while in low-income areas, food losses are the consequences of non-efficient products’ management and storage [7
In this context, consumers have an important role considering that the food choices and behaviors have a clear impact on domestic waste production. As highlighted by Schanes et al. [8
], families showed ambivalent attitudes towards waste prevention, between good intentions to waste reduction and personal preferences regarding food safety, taste, and freshness. As shown by Rohm et al. [9
], a factor influencing consumers’ food waste is the refusal of products with imperfect physical appearance still proper for human consumption such as crooked cucumber, broken biscuits, or products in deformed packages or products that have a best-before date which is approaching or passed, but that are still perfectly fine to eat. Besides this, several socio-demographic determinants affected household food waste (age of children in the households [10
], gender, education [11
], income [12
], composition and number of members of the household as well as culinary and buying food habits [13
]). Moreover, the economic implications of food waste are considered more relevant for people than social or environmental consequences [8
A study carried out by Philippidis et al. [14
], that used a system-wide modeling approach to simulate the prospective economic impacts of reducing household FW by 2030, showed that a 50% reduction in household food waste would lead to a per capita saving of €93 for EU families. In the report of the Waste and Resources Action Programme (WRAP), the amount of avoidable FW generated each year by an average British family is approximately 210 kg, corresponding to €565.7 [15
]. Data on FW domestic economic value are limited and collected with non-comparable methodologies. In an average Finnish household, FW accounted for €70/person/year according to Katajajuuriuri et al. [16
]. Von Massow et al. [17
] reported an FW monetary value of €15.31/family/week in Canada. A Tunisian study based on self-respondent questionnaires showed that 42.7% of participants realized they lost more than €5.10/month for domestic FW [18
]. A study conducted among South Korean households assessed the cost of disposal and any other costs associated with FW quantifying in €2.90 the economic value of daily domestic FW for each family [19
]. According to Notarfonso et al. [20
], the economic value of food waste and loss along with the whole FSC in Italy is about €13 billion a year, with an average of 149 kg of food wasted per person.
In 2018 a first nationwide and country-representative measurement of Households’ Food Waste in Italy (HFWI) was carried out to quantify the food wasted off, to identify the food categories mostly wasted, and to evaluate in which conditions foods were thrown away. Results of this survey are reported in Scalvedi & Rossi [21
]; in brief, for each family, the average quantity of food waste was 370 g per week with perishable products, such as fresh fruit and vegetables, bread, and milk that were most discarded. Considering the growing interest in socio-economic aspects of food waste [22
], the team of the Italian Observatory of Food Surpluses, Recovery and Waste, in 2019, carried out a further study to evaluate the amount of food waste in weight and monetary values concerning the overall quantities of food purchased and the money spent for food commodities by the Italian families. Results of this assessment are presented and discussed in this paper that was conceived to answer the following research questions: (i) how much food is wasted compared to what is purchased in an Italian household? (ii) How much is the burden of the monetary value of the food wasted off on food expenditure of Italian families? (iii) Concerning waste and monetary value of commodities, is it possible to distinguish and characterize them based on the different food categories?
The results presented in this article contributed to adding information on the impact of food waste generated at the very end of the food supply chain, at the consumer level. According to our data, Italian families discharged 3.8% of the weight of the food purchased, losing 4.4% of the economic value of the money spent for food. We decided to focus on the assessment of the economic value of food waste at the households, considering the importance of this aspect in the general debate on the evaluation of money wasted for producing food that is not used for human consumption. According to Vittuari et al. [28
], food waste has a hidden burden because it can be considered as a “double waste” of energy: metabolic energy that is lost for food that is not eaten, and energy for food production that is lost when food is discharged. In addition to that, according to von Massow et al. [17
], avoidable household food waste is a substantial contributor to global heating for the effect of greenhouse gas emissions, inefficient agricultural land use, and water loss. As mentioned, halving per capita food waste is one of the objectives fixed by the United Nations among the Sustainable Development Goals. Thus, the quantification of all the phenomena related to food waste is of key importance for monitoring purposes, especially in a context such as Italy, in which data on the monetary value of food waste is still anecdotal and collected at the local level often with estimation, not with measures, and published as grey literature [29
In the light of these considerations, the absolute figures provided on weight and monetary values of food wasted off by the Italian families are relevant seeing the general lack of this information in Italy, to the best of our knowledge. However, the added monetary value of this paper is the analysis of the different food groups and the different effects on the waste of products about their prices and respect to the quantities that were normally bought. According to present data, in Italy, waste is mainly unused or partially used and in general, all the food that is cooked is consumed, leading to a generally small proportion of leftovers. Among the discarded unused food, there is a polarization related to price and weight, with food with high unitary cost that impacts less in the weight of food waste (Cluster 1) and food with low unitary cost that is thrown away in large quantities (Cluster 3). This is regardless of the perishability of the items; in fact, fresh foods are present both in Cluster 1 (e.g., meat, fish) and in Cluster 3 (e.g., fresh fruit and vegetables). This is in line with the general attitude of Italians to pay more attention to the issue of food waste essentially for ethical and economic reasons [31
]. The economic crisis of the last decades could explain this finding as reported in a survey carried out by the National Confederation of Farmers [34
] in 2011, in which the observed reduction of food waste was correlated with economic difficulties of the families. Among the measures taken to reduce food waste, it was reported there was an increased attitude to buying wisely (47% of respondents), a reduction of the quantity of food purchased (31%), increased use of leftover for other meals (24%), and the most attention to expiration dates (18%).
The issue of personal abilities as a means to reduce food waste is reported also by Janssens et al. [35
], in a study showing that consumers did not have sufficient attention at the early stages of spending management, but they can compensate with correct knowledge of food conservation practices resulting in a small number of products thrown away, especially for the most perishable commodities (meat, fish, fresh fruit, etc.).
There is a consensus on the fact that the perishability of products is a determinant of food waste. In a review of several EU national studies, De Laurentiis et al. [36
] showed that a proportion ranging from 44% to 47% of household FW is attributable to fresh products (fruit and vegetables). The same results were reported by Katajajuuriuri et al. [16
], showing that vegetables and potatoes, fruits and berries, meat, fish, and ready-to-use foods such as pizza, burgers, etc., are wasted off more than long-lasting items. Even during the COVID-19 pandemic, fruits and vegetables were the foods most discarded by families of different nationalities according to the study of Filho et al. [37
]. In addition, our data of the HFWI confirmed this point [21
], which is in line with data coming from other European Countries [23
]. The added information of the present study is related to the fact that among the perishable products, the most wasted off are those with the lowest unitary prices that are also bought in the highest quantities.
Shopping purchases of individuals have a huge impact on the level of FW, as reported by Fanelli [40
] in an exploratory online survey carried out in Italy showing that the amount of food that is thrown away decreases when individuals buy foods in small markets and with a weekly frequency of two times/week or more. In our survey, only purchases done in large retail chains have been recorded by the GFK Consumer Panel, missing the food purchases of local markets or small stores. Thus, probably, what we observed in Cluster 3 is related to the behaviour of buying large quantities of food at low unit costs for the entire week that led to the increase in throwing away large quantities of perishable products.
The three clusters resulting in our analysis are characterized by a gradient in the amount of waste, with Cluster 1 having lower quantities of food waste than Cluster 2 and 3 and the waste quantity gradient is a direct consequence of the unitary prices of the items included in the 3 groups. Another aspect that could explain the differences observed in the three clusters is related to the Italian food habits and frequencies of consumption [41
]. Most of the foods included in Cluster 3 are consumed daily or more than twice a day such as fruits, vegetables, bread, non-alcoholic beverages (that include milk), and yoghurts. On the other hand, Cluster 3 included foods that are consumed every week such as meat, fish, cheese among basic foods, and candies, crisps, nuts, and alcoholic beverages among comfort foods. This is another interesting polarisation of food groups that could be explained by the different attitudes of planning food purchases. We could speculate that large quantities of foods that are consumed every day and several times a day are more likely to be bought in incorrect quantities than foods that are consumed less frequently. Modalities and frequencies of consumption could explain the food items that the procedure of analysis included in Cluster 2. Pasta, rice, vegetable were wasted off mainly as leftovers, being long-lasting products, so unlikely to be wasted unused, and consumed as ingredients in recipes’ preparations. Waste as leftovers is less common in Italy than other types of waste, as confirmation of the fact that Italians tend to eat all the foods they cook [43
Overall, in our sample, 399 kg of foods in one week were wasted off out of the 9.157 kg of foods purchased, with differences across the food categories. The high weight of foods wasted indicates that food waste substantially affects the overall quantities of food purchased. This may occur if the consumer is not fully aware of the correct storage practices, such as for “Potatoes and Preparations” or “Bread”, the categories with the highest proportion of weight on waste. Similarly, for “Yogurt, pudding, and fresh snacks”, waste resulting from a limited knowledge of how and/or for how long the product can be stored. “Rice or cereals” are wasted more than “Pasta”, even if they are purchased in smaller quantities, and this may depend not only on a lack of storage information but also on insufficient creativity in the use of these products once cooked. As mentioned, these items are also most wasted off as leftovers.
The comparison of the food waste ratio indicators—weight and economic value—on food purchases across food groups (Figure 4
) showed that when the rate in weight is greater than that in monetary value, this corresponds to an average cost of foods wasted off lower than the average price of the category as it is for “Potatoes and potatoes-based food”, “non-fresh fruit”, “Rice”, “Breakfast cereals”, “Pasta”, and “Fish”. On the contrary, as happens for “Bread” and a few other products, when the proportion of waste in value is higher than that in weight, the wasted quantity has an average price higher than the average purchase price of the food’s items of the category. Similar percentages corresponded to similar prices of food wasted off and food purchased.
The overall value of FW found in this study was €1.052 out of €27.611 of the weekly food expenditure of the assessed families. This led to a value of waste of €0.92 per family per week. A value that is quite far from those found in the literature that reported, €15.31 [18
] €5.10 [19
], €2.90 [20
], and €70 [17
]. There are objective difficulties of comparisons of crude data of the monetary value of FW collected with various methodologies and in different contexts in which the cost of living and the impact of the cost of foods on family income is very different. At the national level, our data are lower than those reported by Waste Watcher [44
] in 2021, which claimed that Italians throw away 529.2 g of food per week per person, considering what is left on the plate, in the fridge, and kitchen store cupboard. In 2020, the same group reported that Italians wasted €4.90 weekly per household for a total of about €6.5 billion, a decrease of 25% compared to the monitoring in previous years [29
Our figures on the value of food waste are related to the food expenditure as registered by GFK on the consumer panel corresponding to €27.611 per week of the assessed families (1.142), corresponding to a monthly amount of €97 per household. However, as reported by the National Institute of Statistics, in Italy, the food expenditure accounted for €462 per month for each family [25
]. This means that our data underestimate the measurement. Several reasons could explain this underestimation: differences among food groups of the two assessments and the fact that data registered by GFK are related to large retailers’ supermarkets, without considering other food purchases sources such as local shops and neighbourhood markets. In addition to that, the National Institute of Statistics survey [25
] has a different methodology with a large sample size continuously monitored across the year while our assessment is a timely data collection limited to four weeks in 2018. The underestimation of overall food expenditure consequently determined an underestimation of the economic value of food waste. This is the most important limitation of this study. Data on food waste collected with recall questionnaire underreported the absolute quantities in comparison to diaries or direct analysis of waste compositional analysis [24
]. The mechanism of underreporting of food waste with the use of a recall questionnaire is similar to those found in the studies on food consumption in which people recorded less food than they eat, underestimating consumption by a considerable margin, which in Italy was estimated at 29% [41
]. Despite underestimation, the national food consumption data were considered a reference for the population. Although direct measurements of food waste produce more accurate results, these require most of the expertise, time, and cost. Direct measurements would be more appropriate in research settings than for monitoring. On the other hand, with the same approach used for the establishment of a nutritional surveillance system [45
], it is possible to use data on food waste at the population level also with methods that underestimate the phenomenon, clarifying the purposes of data collection. This will allow one to estimate the extent of the problem, to bring together the data to identify specific groups, to provide information that allows the development of corrective actions, and, through continuous monitoring, to evaluate the effectiveness of the interventions themselves. The authors considered that the data reported in this paper fit with the idea of surveillance as described. Even though the absolute figures reported of the household’s monetary value of food waste have the mentioned limitations, to the best of our knowledge, this is the first attempt at its quantification at the national level with data representative of the Italian population.