Fallback food or traditional vegetables are terms describing the groups of secondary food resources of people from a particular geographical region or a particular culture [7]. During difficult times where resources were scarce, unusual foods were consumed to fight hunger and provide the crucial nutrients required for survival. These foods were referred to as “famine food.” Over time, famine foods were no longer consumed by necessity but as an integral part of food culture [23]. Snails, rotten cheese with maggots, and bread with clay are still commonly consumed in Sardinia and are considered to be delicacies passed down from their ancestors [8]. Due to the unusual nature of these foods, they are often viewed as food taboo by the outside world while being cherished as intangible cultural heritage and treasures from ancestors [24]. “Neglected foods” around the world are similar in that although they are unappealing to modern consumers, they are proven to be rich in nutrients, sustainable, and benefit health in the long term [25]. Traditional and famine foods in Sardinia include abbamele, acorn bread, pane carasau, caggiu de crabittu (Callu de Cabreddu), casu marzu, snails, bottarga, and many more.
Abbamele
Abbamele is one of the oldest honey-based products recorded in Sardinia and consists of honey, pollen, water, and honeycomb [26]. To make the abbamele, honey is first extracted from the honeycombs. Subsequently, the honeycombs are crushed and dipped into warm water to separate the wax from pollens and residual honey. Lastly, orange peel or lemon rinds are then added while boiling the concoction until a brownish product with water content between 17.7 to 27.7% is obtained. This is vastly different compared to conventional honey, which is produced in several steps. The first step is to filter out the beeswax, pollen, and other particles [27]. Following filtration, the honey is heated to between 60 and 65 °C to concentrate the honey to around 17% moisture content while maintaining the color and flavor by minimizing caramelization. Lastly, a high-temperature treatment is applied for a short duration to destroy microorganisms. Compared to conventional honey, abbamele features a richer flavor and more micronutrients. Polyphenols in honey products are known to prevent heart diseases [28], while pollens collected by honeybee are known to have antimutagenic, antioxidant, and anti-inflammatory effects that are attributable to its phenolic compounds, particularly to the flavonoids [29]. A similar production method is also performed by natives from southern Portugal to produce the nutrient-rich Água-mel [30]. Currently, handcrafted abbamele is one of the most sought-after Sardinian foods and is sold at prices that are up to tenfold greater than traditional honey [26].
Acorn bread
Acorn is the nut produced by oak trees, and although widely available, it is rarely consumed on a daily basis. Acorn contains a high amount of tannin, which is known to be toxic to humans and many mammals [31]. To prepare Pan’ Ispeli, the acorn bread, acorns are crushed and soaked in water to leach out some of the tannins and reduce the toxicity [32, 33]. Clay is then mixed with the acorn meal to further counter the toxicity of tannin and the bitter taste. The clay also provides the pitch black color of the Pan’ Ispeli. Geophagy, a term describing the consumption of soil, is still practiced in the poorer countries of Africa.
Currently, acorn bread is no longer a part of the traditional Sardinian diet. However, the bread is still prepared and consumed during celebrations and festivities [33]. Locals who still possess the skill to prepare Pan’ Ispeli take pride as they pass down this knowledge, tradition, and wisdom from their ancestors, who were able to survive the harshest times of extreme hunger.
Pane carasau
Pane carasau is a traditional Sardinian sourdough flatbread made with durum wheat flour, yeast, water, and salt [34]. The bread is prepared using a double baking technique which is designed to lower the water content much further than common flatbreads. As a result, Carasau can be stored for several months without losing its sensory characteristics [35]. The long shelf life was also essential to the shepherds as their lifestyle is nomadic, and they often did not have access to perishable food [36]. Studies have revealed that the strains of lactic acid bacteria in the sourdough used by the locals produce special sets of peptides and γ-aminobutyric acid with antihypertensive effects [34]. Moreover, pane carasau has a low glycemic index, which helps to reduce the risk of chronic diseases such as diabetes. Therefore, pane carasau not only nourished Sardinia’s ancestors during difficult times, the healthy composition of this food might have played a crucial role in their longevity.
Caggiu de crabittu or Callu de Cabreddu
Caggiu de crabittu, also known as Callu de Cabreddu in some regions, is a traditional Sardinian food consisting of edible goat rennet (EGR) with soft cheese inside [37]. The word “Caggiu de crabittu” is translated to as a kid’s rennet in the Sardinian language. This unusual cheese is produced by ripening goat milk inside the abomasum of a young goat for between 30 and 60 days. The abomasum is shown to be free of pathogenic bacteria also contains a significant number of mesophilic lactic acid bacteria species (i.e., Lactococcus lactis, Lactobacillus plantarum, Lactobacillus paracasei, to name a few). Rennet contains special proteases and lipase enzymes that release short- and medium-chain free fatty acids (FFA), contributing to this cheese’s flavor [38]. The raw milk, diversity of the lactic acid bacteria, and abundance of FFA provide many health benefits compared to modern cheese, such as improving protection against allergic or atopic diseases, promoting gut health, and improving anti-inflammatory activities [39]. Initially, Sardinian shepherds used the abomasum as a pouch to carry food. This spreadable soft cheese is often consumed with pane carasau to provide a nutritious, healthy, and sustainable meal. Nowadays, caggiu de crabittu has become a signature Sardinian cheese due to its unusual production method and flavor.
Casu marzu
Casu marzu is another unusual cheese of Sardinia. The word casu marzu translates to “rotten cheese” in the Sardinian language [40]. To make this cheese, goat milk is first curdled with rennet and then placed in brine for a day. During the following 15 days of ripening, the cheese is exposed to piophila casei flies. After fermentation, countless worms are placed inside the cheese. Currently, some producers are using specially reared flies in captivity to ensure food safety [41]. This creamy cheese is meant to be consumed with living worms, which is often unaccepted and considered to be distasteful by the outside world (Fig. 2). Despite efforts to control food safety and documentation related to the history of this food, it is not recognized by the European Union Database as a traditional food product [42]. Therefore, the food is not known or appreciated outside of the region, and the sale of it is banned in many countries, including Italy, as the living worms are considered to be carriers of parasites. Studies have revealed that edible insects have countless health benefits [43]. According to this study, edible insects may contain up to 30% of essential amino acids, given that they are very high in protein content, and they could improve human gut microbiota. Another study also highlighted the vast amount of vitamins, minerals, and polysaccharides that aid in enhancing human immune functions [44]. Although rejected by most of the world, it is shown that this specialty cheese offers a vast amount of health benefits, while controlled production could guarantee food safety and hygiene. Without any doubt, Case Marzu plays an important role in the longevity of Sardinian people both as a symbol and thanks to its rich nutrients.
Snails
Snails have been consumed as famine food since the Palaeolithic era in the Mediterranean region [45]. Snails are considered taboo in most parts of the world as the mollusk is believed to be unhygienic. However, studies have shown that pathogens such as E. coli 157, the Hepatitis A virus, and Norovirus are not detected on farmed land snails, and they are therefore as safe as other reared animals [46]. Similar to the worms found in Case Marzu, the snail is very nutrient-dense. They are also known to have a very high percentage of polyunsaturated fat-to-saturated fat ratio (44.06% to 20.39%), which is healthier than red meat [47]. Snail meat is also known to prevent diseases linked to mineral deficiencies such as night blindness, osteoporosis, postpartum hemorrhage, and hypophosphatemia [48]. Therefore, the snail is, in fact, not only safer than most have imagined, but the food also provides much-needed vitamins and minerals, which are crucial to healthy during harsh times.
Bottarga
Bottarga is a traditional Sardinian food product made by salting and drying the ovaries of mullet fish [49]. Bottarga is different from most other fish roe products, given that this roe is directly cured inside the ovary as opposed to being extracted first. The ancient production method has been recorded since the seventeenth century [50]. Bottarga can be stored for up to 3 years thanks to its low moisture and high salt content, as well as the protection provided by the dry ovary. Bottarga is known to contain a high percentage of proteins, minerals, vitamins, and most importantly, n-3 polyunsaturated fatty acids (PUFAs), better known as omega-3 fatty acids [51]. PUFAs are known to be beneficial to the human body and are able to lower blood cholesterol and prevent other diseases and disorders. However, PUFAs are known to oxidize when exposed to light, air, or heat rapidly. It has been revealed that thanks to the preparation of bottarga with the original ovaries, less ideal storage conditions result in much lower damage to the lipid components and color of bottarga [52]. Currently, Sardinia is famous for the production of bottarga and other roe with ovaries [53]. The ancestors of Sardinia produced this cured roe in order to preserve food during famine times. Unknowingly, this preservation technique also helped to maintain the quality of PUFAs as well as many other beneficial but difficult to preserve nutrients linked to longevity. Nowadays, bottarga is recognized as a gourmet delicacy, while it was previously considered to be a hunger food and consumed during difficult times when fresh foods were scarce.
There are many other ancient Sardinian foods, such as Treccia, a roasted lamb intestine dish, horse steak, pigeon, sea urchin roe, and seeds from Boraginaceae plants [54]. Some have been recognized as a delicacy, such as a sea urchin roe [55], while other foods, such as Boraginaceae seeds, are now gaining popularity due to their nutritional value [56]. However, most of the ancient Sardinian foods are still considered taboo by the outside world. The resourcefulness and ingenious preparation methods allowed the ancestors to prepare and preserve foods other civilizations had to discard. These unusual foods not only helped Sardinian people to survive during famine time, but their surprisingly nutritious properties also improved the health and longevity of the locals. Moreover, the preparation of the famine food also acted as a guide of lifestyle, which, in turn, promoted a longer lifespan.