1. Introduction
In recent times, food wastage has become a frequently investigated issue. In countries with developed economic status, the largest quantities of food waste are generated at the consumer level [
1]. The ratio of household food waste in the EU is estimated to be about 53% of the amount produced within the entire food chain, which equals 92 kg per capita annually [
2]. Reported numbers are mainly originating from calculations based on general waste databases of the member countries. In the last ten years, research activity has been accelerated in this field, delivering a variety of—sometimes contradictory—results. The greatest research activity in the field is focusing on Northern and Western Europe (prominently Denmark, Finland, Germany, Italy, Norway, UK) [
3], but there are several examples outside the continent as well (USA, China, Canada) [
4].
The majority of the variation in reported empirical data can be explained by the wide range of methods used by the studies. There are quite a few direct research methods that can be applied in research practice to acquire primary data on the extent of household food waste [
5,
6]. Several reports used questionnaires, where the focus is on self-reporting [
7,
8,
9,
10]. Physical measurements, such as diaries or composition analysis, are also widely used methods [
11,
12,
13,
14,
15,
16,
17]. Nevertheless, we must take into consideration that these methods entail a great deal of uncertainty [
18]. For instance, separately collected organic stream could contain other biological waste besides food (flowers, green waste from the garden or the street), while other elements could be missing (food put in general domestic waste, poured into the sink, or fed to animals) [
19]. A significant gap can be detected between the amounts resulted from physical measurements and self-report surveys [
17,
20,
21]. Self-reported numbers tend to be significantly lower than physically measured values. Physical measurements, however, require a serious commitment from family members and a great amount of trust invested in the researchers. Moreover, gathering an appropriate sample size in physical measurement surveys is a very challenging endeavor. Despite the known hindrances of the discussed research methods, it must be noted that acquiring reliable and detailed information on household food waste is of great importance [
22]. A recent study argues that physical measurements for data collection instead of self-reporting are preferred [
23], because of their higher reliability.
In the case of Hungary, the only study based on the physical measurement of household food waste was conducted in 2016 [
24]. The measurement involved 100 households during a one-week period. Besides solid food items, liquid waste was also measured, which was later considered to be an essential element of food waste accounting [
6]. Based on the results of this study, 68.04 kg of food were wasted in average by a Hungarian person annually, and out of it 33.14 kg would have been avoidable. Similar results have been found by a Greek study, involving 101 urban households [
15]. After the 14-day measurement period, the assessment of the total per capita food waste resulted in 76.1 kg, of which 25.9 kg considered as avoidable. The proportion of the avoidable part was proven to be relevant in Finland too, 23 kg per person annually [
12]. The differentiation between avoidable and unavoidable food waste is recommended and applied in the vast majority of measurements [
11,
12,
16,
17,
23,
25,
26].
The composition of household food waste varies from country to country. However, it is found that generally the most perishable food items are thrown away the most frequently [
27]. With respect to the avoidable category, these food items include fresh fruits and vegetables, bakery products, and dairy products. According to the previous Hungarian study, the main types were meals, bakery products, fresh vegetables, dairy products, and fresh fruits [
24]. In Serbia, though in reverse order, bakery products and ready-to-eat food items were on the top of the list as well [
28]. Bread and bakery products were observed to have the highest ratio in Norway as well, based on a waste composition analysis [
14]. Contrastively, fresh vegetables and drinks have been found to be the most prevalent types in the UK [
11]. Vegetables were observed to be the most commonly wasted food items in Denmark, Greece, and Israel [
13,
15,
16].
In order to reach the Sustainable Development Goal 12.3, halving the amount of food waste by 2030 [
29], it would be essential to determine the magnitude of the problem that we face. According to a recent study, 15-16% of the total environmental impact of the food supply chain is derived from food waste [
30]. It can also be stated that food wastage is in constant increase (especially in developed countries), and the actual quantity of food waste seems to be twice the amount of the results from previous global estimates [
31]. Physical measurements, especially in households—a sector that accounts for the most significant part of food waste in the food chain—play a central role in refining national statistics [
24]. However, this poses a particular challenge, since the lifestyle, consumption trends, and purchasing habits are in continuous change [
32].
Recently, the importance of food waste measurement has become a major concern also at the European Union legislative level. Until 2020, the member states have to integrate a food waste reduction strategy into the national waste reduction plan. Furthermore, food waste prevention campaigns have to be established at the national level [
33]. The European Commission has recently issued a decision establishing a common methodology and determining the minimum quality requirements for food waste data collection [
34,
35]. The national food waste reduction strategies should be based on the actual numbers, which have to be updated every four years. Measures aiming at food waste reduction may pose an elevated health risk to consumers (for instance eating expired food or offering it to charity, feeding potentially infectious food to livestock or companion animals). Therefore, communication campaigns, governmental institutions, and business organizations should handle food safety questions as a priority during food waste reduction efforts [
36].
The aim of this research was to estimate the amount of food waste that an average Hungarian household generates based on a one-week period. This investigation was a replication of a household food waste measurement conducted in 2016 with the same methodology, within the boundaries of the Wasteless (Maradék nélkül) food waste prevention campaign, organized by the National Food Chain Safety Office in Hungary.
3. Results
During the measurement period, the 165 participant households generated 532.76 kg of food waste (
Table 2). After extrapolation of the one week data per capita, the total per capita food waste was estimated to be 65.49 kg annually (
Table 3).
The proportion of the avoidable fraction (which means the real wastage) was the highest, with 48.81% (31.97 kg annually) of the total food waste. The unavoidable food waste category accounted for 47.04% (30.81 kg annually). The most prevalent food types within this category were coffee grounds, inedible fruit and vegetable parts (inedible peels such as banana peels, citrus fruit peels, onion peels, and inedible stalk, woody parts, seeds, shell of nuts, etc.), bones, eggshell, and teabags. The potentially avoidable part, such as edible fruit and vegetable peels (e.g., apple, pear, cucumber, tomato, mushroom, zucchini), chicken skin, bread crust, greasy pieces of meat, pickling liquid, juices of canned food, and oil of canned fish represented the smallest proportion, with 4.16% (2.72 kg annually). Liquid food, such as soft drinks, coffee, tea, and soup appeared in the logs in significantly lower amounts compared to solid foodstuffs (
Table 3).
Eighteen different food categories were defined based on the recorded elements within avoidable food waste. Results suggest that consumers discard perishable foodstuffs more frequently and in larger quantities than durable products.
Table 4 shows the mass and proportion of the established food waste categories.
Meals (including homemade and ready-to-eat) account for the highest proportion (44.74%) of the total avoidable food waste. Bakery products (typically breads and bread rolls) are the second most common food items in this category (17.62%). Fresh vegetables and fresh fruits have also significant proportions, 10.00% and 7.54 %, respectively. Dairy products ranked in the fourth place of the list (7.95%). These five product categories altogether represent almost 88% of the total avoidable food waste.
Based on the actual data collected from the households, the quantity of annual avoidable wastage in the particular food categories has been estimated with extrapolation (
Figure 2).
4. Discussion
Due to the role of consumers in food wastage in economically developed countries, gathering actual data on food waste generation from households is a major issue and a prerequisite for successful prevention campaigns [
22]. Since the reliability of physical measurements is higher [
23], our research placed the focus on determining the exact quantities of food waste that Hungarian households generate. The study illustrates several similarities and also some contradictions when compared to the international literature.
The actual study is a replication of the first Hungarian measurement-based research conducted in 2016 [
24], which we regarded as a baseline for comparison. A decrease of 4% in the annual food waste per capita estimation was observed between the two periods (65.49 kg compared to 68.04 kg from 2016). The constitution of food waste in the households was found to be very similar, indicating a dominant rate of avoidable food waste (an actual share of 48.82% compared to 48.70% in 2016), followed by the unavoidable part (47.05% compared to 47.13% in 2016). Potentially avoidable food waste remained under 5% in both periods. (
Table 5). Although the second household food waste measurement study was not organized and not suitable to be a validation of the replicability of the FUSIONS methodology [
38], the results suggest that it might deliver reliable data for decision makers.
As already discussed, a number of methodological differences can be observed in the international literature that limits the comparability of the studies [
16,
26]. The proportion of avoidable food waste observed by the two Hungarian studies is higher than in Greece, where 25.9 kg from the total 76.1 kg household food waste (n = 101) was reported based on the diary method [
15]. In Finland, a significantly lower amount of avoidable food waste was also found (23 kg in total) [
12]. Similarly, a lower proportion (35%) of avoidable waste was noted in Sweden, as a result of a waste composition analysis with 486 households [
52], in which the number of individual consumers remained unknown. The differences might partially be explained by the fact that the Hungarian studies have also recorded liquids besides solid food waste, and their contribution to the avoidable part was found to be significant. However, an Italian study—applying the diary method with 388 families—demonstrated that a person generates 27.5 kg of avoidable food waste annually in Italy, including liquids [
17]. They also pointed out that, based on the studies that they had reviewed, the average mass of edible food waste was between 27.5 and 33 kg. The diary method was also employed in the UK, in a one-week measurement survey involving 13 households [
48]. The study revealed that the total measured food waste (including liquids) was 0.199 kg per person per day. This would be equal to 72.63 kg annually, which is higher, but still similar to our results. In Israel 573 g/day per capita of food waste was measured involving 192 households, based on a new method of physical measurement [
16]. Scaling up this outcome to one year, we would get 209 kg, which is much higher compared to the above-mentioned studies. A further hindrance to comparing international food waste research data are the units that researchers use to present their results. While some studies—including the present paper—provide the amount of generated food waste “per person” [
12,
15,
16,
17,
48], others presented their results “per household” [
13,
14,
17,
20,
41]. The one-week long household food waste measurement study in Israel, applying waste sorting analysis, resulted in 3.012 kg avoidable food waste per household per week (without liquids) [
20]. In Denmark, the outcomes of a waste composition analysis (involving 1474 households) showed that a household generates 183 kg of food waste, of which the avoidable food waste was 103 kg per household per year [
13].
Parfitt et al. made the general observation that perishable food items are the most frequently discarded ones [
27], which has been confirmed by this paper as well. Results indicate that meals, bakery products, fresh vegetables, dairy products, and fresh fruits are the most frequently discarded food types within the avoidable part. This also correlates with the outcomes of the first Hungarian study [
24], which indicated the same order. However, the share of meals appeared to be higher (44.73%) than in the previous study (40.08%), which suggests that Hungarian consumers’ cooking habits and leftover storage practices should be addressed in food waste prevention awareness campaigns. Similarly to our study, bakery products and ready-to-eat food items were found to be the most prevalent food waste types in Serbia [
28]. In contrast, fresh vegetables were on the top of the list in the UK, Greece, Denmark, and Israel [
11,
13,
15,
16,
52]. The discovered differences in the composition of household food waste may be explained by the eating habits of different nations. It has been assumed that the season when the survey period is conducted also affects the composition of discarded food types [
24].
Concerning the limitations of the general interpretation of the data, it has to be mentioned that the recruitment of households was challenging, as well as achieving participant engagement and constant activity, even for a period as short as seven days. An additional potential source of error is the fact that, since the research team was not capable of offering a financial incentive, enthusiastic participants with a more conscious behavior regarding food handling were more likely to get involved in the study [
12]. However, we assume that the other family members compensated this behavior to some extent. Furthermore, in the measurement period, participants might have changed their general wasting behavior and become more conscious, knowing that they were being observed, which could have resulted in lower amounts of weighed total food waste [
15]. It could also have happened that, due to the compulsion to conform, originating from the fact of observation, some participants did not record all of the discarded food items. On the other hand, the duration of the survey could be long enough to alleviate this phenomenon to some extent. An additional limitation of the study was that income level is difficult to assess, compared to other socio-demographic parameters [
53]. Asking the respondents’ income directly would have been indiscreet, and therefore a subjective ordinal scale was applied in the questionnaire. All of the mentioned limitations could result in an underestimation of the actual food waste amount generated in the household. However, by the application of the standardized methodology developed by FUSIONS, research data from different countries could be compared, and the possibility to observe tendencies in the different countries was also provided.
The importance of a common methodology is especially highlighted by the recent changes in EU legislation. According to the latter, all member states should conduct food waste measurements in the food chain covering agriculture, food processing, retail, catering, and households from 2020. Considering the major contribution of households to the total food waste production, this subject is expected to be a focus area in most of the countries during the next years. The EU Platform on Food Losses and Food Waste made the recommendation that in implementing national strategies to prevent food waste, member states should make full use of the latest findings of behavioral science research [
37]. The experiences of the first academic studies in this field have certainly provided important input for the officers responsible for national level food waste measurements and preventive campaigns. Even more importantly, time series studies will help decision makers and communication experts to measure the performance of public awareness campaigns within a few years.
As a conclusion, the results of this research point out that a very significant part of food waste could be avoided. It is too early to reliably estimate the results of public campaigns before having longer time series data, but the first replication study using the FUSIONS methodology provided promising results. The 4% drop in avoidable food waste in a three-year period is notable, especially in a period of economic expansion. However, the fact that the list is still dominated by meals (incorporating the highest level of energy and natural resources amongst all food types) suggests that future public awareness campaigns should aim at this subject more efficiently.
Based on the results, some policy recommendations could be also formulated. Fostering national-level food waste measurement research with standardized methodologies is essential to establish the fundamentals of effective governmental interventions and to allow for the international benchmarking of preventive actions. It is also clear that food waste is a problem, which will persist for a long period in developed countries. A very intense campaign, which was observed in Hungary between the dates of the two studies, could contribute to a 4% drop in food waste, with all its novelty to society. While awareness raising should be continued, a major effort has to be placed on the integration of food waste prevention principles into children education. To be sure, we will never reach a zero level of avoidable food waste, but changing the habits of the new generation of food consumers can bring profound and long-lasting changes.