Minimizing amount of waste and unnecessary usage of resources is among the principles of sustainable consumption [22]. Preventing food waste is essential, since food waste embodies uneaten food and all input used in its production (e.g., cropland, fertilizers and pesticides, water, feed of animals, energy, human resources, etc.) [23,24]. In addition to environmental impacts, ethical (e.g., fighting against hunger) and economic (e.g., production costs, household budget) aspects are not negligible [25].

Food waste arises in every step of the food chain; thus, mitigation should be a common goal, and responsibility is shared among food-chain actors [26]. On the consumers’ side, raising awareness and promoting good practices are especially important. EU countries should establish food-waste prevention programs according to the Directive (EU) 2018/851 [27]. In transposition of the Directive, several countries are implementing national waste-management plans and measures to reduce food waste. For instance, Bulgaria introduced the National Waste Management Plan 2021–2028 [28], the Greek Ministry of Environment set a strategic goal for the period 2021–2030 [29], Hungary aims to reduce food waste and losses through the National Waste Management Plan 2021–2027 [30], and Romania ordered the “Government Decision 92/2021” on its waste regime [31]. Incentives such as tax deductions for companies that save food by donation are also present in some EU countries [32]; this is an effective food-waste reduction policy that was introduced several years ago.

Changing habits about food waste is challenging. Consumers are usually not aware of their role in food-waste production, similarly to their awareness of their role in maintaining food safety [33]. In both areas, they often blame food-industry and hospitality units for foodborne illnesses and high amounts of food waste. However, the highest ratio of occurrence of diseases and proportion of wasted food is linked to household practices [34,35,36]. According to Skuland et al. (2020) [37], ignorance of the expiration date of perishable products, inadequate treatment of spoiled food, and irresponsible handling of leftover meals in order to avoid food waste are among the most common food-safety problems at a consumer level. As Watson and Meah (2012) identified [38], household budget, ethical issues and sustainability issues are often more important to consumers than minimizing food-safety risks.

A common problem is that people do not pay attention to the labeling of expiration dates either during shopping or at home, nor are they aware of different types of expiration dates [39]. More than half of consumers do not recognize the difference between use-by and best-before dates [40], resulting in approximately 10% of food waste [41]. In the case of perishable products, it is a common belief that use-by dates are overly cautious and therefore food can be consumed safely for 1–2 days after the expiration date [42]. Additionally, edibility of these products is frequently “probed” based on sensory characteristics, although the presence of pathogens (including viruses) and their toxins is usually not accompanied by changes in taste, smell, or texture of food [43]. Other “at-home tests” or traditions for checking the safety status of food products also failed when academics tried to validate them. For example, putting eggs into water to check freshness does not indicate the presence of Salmonella [44,45]. However, consumption of eggs after expiration date is a common and risky habit in some countries [45]. Long-shelf-life foods—foods with a best-before date—regularly end up in the trash, generating unnecessary food waste once the expiration date had passed by only a few days or weeks [46].

Regarding spoiled, moldy food, a false public belief is that removing visibly contaminated parts can save the product [47,48], a practice which is frequently observed when handling cheeses, bread, jams, fruits, and vegetables [37,49]. Possible reasons for this risky behavior stem from various negative emotions about discarding seemingly salvageable food [6]. Some people decide to use moldy products (even when a certain level of risk is recognized) under time pressure, for instance when being in the middle of cooking and the concerned ingredient is essentially needed.

Generally, consumers do not understand that invisible hyphae of molds are extended to the entire food. Several fungi species produce mycotoxins that cannot be detected without laboratory equipment. Moreover, cooking does not deactivate mycotoxins. Therefore, even if a consumer takes those extra steps to make spoiled food safer, the hazard will not be eliminated [49,50]. In a few special cases, some moldy products might still be possibly saved by cutting out contaminated parts (hard cheeses, firm vegetables such as carrots, and hard cured-meat products such as salami) [47,51]. However, communicating such detailed pieces of information to consumers (for instance, the exact types of foods that are suitable for saving, and how much should be removed from the product to ensure safety) is nearly impossible [52]. To keep it simple and safe, it is better to recommend moldy products to be discarded.

Handling leftover meals is important for food-waste prevention but has also proven to be an area of concern regarding food safety, according to Skuland et al. (2020) [37]. Moreover, meals prepared by consumers or their family members are bearing an emotional value, that influences food safety related decisions [6]. Eating leftovers after more than one cycle of storage and reheating or storing at too high of a temperature for too long are among observed questionable practices [37]. Storing food at higher temperatures facilitates microbiological growth; moreover, microbes will become more resistant to heat if food is repeatedly reheated at sublethal temperatures [53,54]. Spore-forming microbes will also germinate after heating and can grow if the temperature is over 4 °C [55]. An extreme but attention-grabbing precedent in inadequate treatment of leftovers is the case of a young adult in Brussels who died of food poisoning caused by Bacillus cereus toxins in poorly stored spaghetti [56].

Another excellent example of sustainability–safety controversy is when consumers focus on saving unavoidable food waste instead of preventing avoidable food waste. For instance, preparing “banana-peel bacon” is now a trending issue among consumers, even though fungicides and insecticides on the peels of bananas may pose food-safety risks even after frying, as most pesticides do not decompose at that temperature [57,58]. Bananas are thrown away in the most significant amount among fruits due to improper storage [59]. Instead of food-saving solutions that seem simple and quick but elevate level of risk, a focus should be placed on methods that prevent food waste and do not compromise food safety [15].

The main problem regarding all the cases mentioned above (ignorance of expiration dates, removing mold, poor leftover handling, saving banana peels instead of whole bananas) is how consumers attempt to solve sustainability challenges by performing risky practices.

Packaging has a multifaceted role in the life cycle of food; it is a physical protective barrier [74] and a communication and marketing platform [75]. It also provides resistance to tampering as well as enabling convenient handling, transportation, and storage [76]. Although these aspects are all important, emphasis is constantly shifting in parallel to changes in legislation and consumer expectations [77], resulting in turbulent evolution during recent decades. Nowadays, expectations towards packaging have become rather complex. In addition to protection and information, sustainability aspects have also come into the light [78].

Although reducing the amount of packaging along the food chain is an unequivocal societal expectation, the function of food packaging in preserving food safety and quality is also unquestionable. Food manufacturers are obliged to comply with current European Union directives and take steps to reduce usage of lightweight plastic carrier bags and withdraw other single-use plastics [79,80]. Different countries use different approaches to implement the European Packaging Directive 94/62/EC [81] into national law. For example, in Croatia, there is a refund–fee system for managing single-use plastic packaging [82]. In France, the “Circular Economy Law” (Law No. 2020-105 of 10 February 2020) focuses on recycling channels [83]. The Portuguese government determined the obligation of non-use of single-use plastics for food [84] and prohibited use of ultralight plastics [85]. Similarly, the UK introduced a complex strategy that includes measures regarding taxes, separate waste-stream collection, deposits on bottles and cans, and stimulation of recycling [86]. However, regardless of the efforts and approaches used, aspects of food safety cannot be compromised at any step of the food chain due to global intention to reduce use of plastic packaging.

Consumers tend to judge packaging in an extremist way; in general, they overestimate the negative environmental aspects of food packaging but underestimate its role in food safety. According to consumers’ assumptions, more than half of the total carbon footprint of a food product is related to the packaging [87]. In fact, the actual data on the carbon footprint ratio of packaging compared to the total carbon footprint of the product is only 1/30 [88]. Consumers tend to consider disposable packaging an enemy, even though it significantly contributes to maintaining food safety and, due to longer shelf life, even facilitates a more sustainable food chain [89]. According to the literature, estimated food loss due to lack of proper packaging has a bigger negative effect on the environment than the positive effect of simplification or complete abandonment of packaging [90,91]. This principle is especially true for food categories with high environmental impact, such as meat products or dairy products [92].

Packaging is the most efficient physical barrier to protect food; unpacked food is prone to food-safety risks. Elimination of single-use packaging results in the spread of reusable packaging materials. Single-use plastic bags—used for bakery products, vegetables, and fruits—not only are convenient but also help to prevent cross-contamination by separating food products. Replacing single-use plastic bags with reusable shopping bags may deliver new types of risks; consumers are often not aware of their own responsibility in maintaining the hygiene of these items (bags, boxes). Non-adequate washing and sanitizing of these containers can lead to cross-contamination. Certain retailers also serve high-risk food products, such as cheese, meat, and cold cuts, to consumers who bring their own containers. The hygienic status of those containers is not guaranteed, so even a safe food can become contaminated by an improperly cleaned box. Bacteria can also be transmitted from boxes to deli-counter tools, surfaces and personnel. Customer-owned takeaway containers in restaurants evoke similar problems. Although they deliver sustainability benefits and represent a cheaper option for consumers (compared to the cost charged for a takeaway box), the hygienic status of home-washed reusable boxes poses significant food safety risk [93]. Guidelines and protocols for retailers and hospitality actors might seem to be too rigorous in certain circumstances [94], but their main objective is to ensure food safety. According to general food-law stipulations, such as in the case of the 178/2002/EC regulation [95], food-business operators bear the primary legal responsibility for the safety of their products and services. However, food-hygiene protocols should accommodate to changing trends. New, improved practices have to be developed with the support of the authorities. For instance, reusable boxes with deposits could be introduced, or restaurants could provide a serving space for user-owned containers in a separate area.

Proliferation of package-free stores has heralded a new horizon in commerce. Even though the protective function of packaging is absent in these cases, the risk of contamination from consumers is significantly higher. The protective role of plastic packaging has been even more appreciated after the COVID-19 pandemic [96,97]. A previous fieldwork study [37] pointed out that package-free bulk products raise consumer concerns about other shoppers coming into physical contact with unpacked food products. The fear of contaminant transmission from people to food can contribute to unsafe food-handling practices in the household, such as rinsing raw chicken [98,99].

Additionally, because packaging serves as the primary communication platform between food manufacturers and consumers, lack of packaging can easily imply a lack of risk-related information for consumers [100]. In the case of bulk products, bulk-food containers in the shop must be equipped with the food label required by legislation, or personnel of the shop should be able to provide information upon consumer request. However, all necessary food-safety information (e.g., expiration date, storage circumstances) [101] vanishes after the product fills the consumer’s own food container, resulting in a possible knowledge deficit before consumption. The deficiency in consumer knowledge can pose food-safety risks and trigger household food waste [102].