Identification of Portuguese culinary recipes used for nutritional composition analysis in,three regions of Portugal.

2. Materials and Methods 2.1. Study Design A pilot study was conducted to evaluate and compare the nutritional composition of traditional Portuguese recipes representative of the three main regions of mainland Portugal (North, Centre, and South), aiming to identify potential regional differences in their nutritional profiles. Recipes from these three major administrative regions defined by the National Institute of Statistics [10] were included in the analysis. Regional delimitation followed the Nomenclature of Territorial Units for Statistics (NUTS II) system, ensuring consistency in geographical classification and balanced representation among the regions analysed. 2.2. Data Collection 2.2.1. Recipe Source Selection The sample consisted of 60 traditional Portuguese recipes, evenly distributed across the three regions (20 recipes per region). Within each region, the selection included six first courses (two of which were soups), eight main courses (four meat-based dishes and four fish-based dishes), and six desserts. Recipe selection was based on two widely recognised reference sources, chosen for their authenticity, historical relevance, and cultural significance in Portuguese culinary literature: - Cozinha Tradicional Portuguesa by Maria de Lourdes Modesto (1981) [4], widely regarded as the “Bible” of Portuguese gastronomy. - Teleculinária magazine (2024) [11], first published in 1976, which became a benchmark in Portuguese cuisine and is currently available exclusively in digital format. Recipes were selected according to the geographical origin indicated in the culinary publications, as well as their cultural representativeness and popularity within each region Priority was given to preparations most strongly associated with local gastronomic identity and still present in contemporary Portuguese cuisine. Cultural representativeness was further validated using the VisitPortugal portal (Turismo de Portugal, 2024) [12] and the Portugal Gastronomias website [13], which identify emblematic gastronomic specialties of each region. The combined use of these sources ensured the cultural and regional adequacy of the sample, ensuring that the selected recipes accurately reflected Portuguese gastronomic heritage. Each recipe was subsequently coded using a numerical system corresponding to region and dish category, allowing systematic organisation and facilitating subsequent statistical analysis (Table 1). Table 1. Identification of Portuguese culinary recipes used for nutritional composition analysis in three regions of Portugal. 2.2.2. Inclusion/Exclusion Criteria Inclusion criteria comprised recipes with a clearly defined regional origin (North, Centre, or South), presence in at least one of the selected reference sources, and preservation of original ingredients and traditional cooking methods representative of local gastronomy. An additional inclusion criterion was the availability of complete information on ingredients and respective quantities, which was essential for nutritional analysis. Recipes lacking precise regional identification, those that had undergone substantial modern adaptations (e.g., substitution of traditional ingredients with contemporary alternatives), or those with insufficient quantitative data were excluded. 2.2.3. Nutritional Composition Assessment For each recipe, nutritional composition per 100 g was determined for the following parameters: energy value (kcal), protein (g), total carbohydrates (g), sugars (g), dietary fibre (g), total fat (g), saturated fatty acids (g), and sodium (mg). These variables allow the assessment of energy density and overall nutritional quality and enable comparison with current European reference values [14]. The number of recipes per region and per dish category was defined to ensure balanced representation of traditional culinary practices while maintaining feasibility within a pilot study framework. This strategy prioritised cultural relevance and methodological transparency over statistical power. 2.3. Data Organization Data collection began with recipe selection, followed by ingredient quantification and calculation of nutritional composition. As many recipes reported household measures rather than standardised units, all ingredient quantities were converted into grams using the reference manual Pesos e Porções de Alimentos [15], ensuring consistency and accuracy. Nutritional composition was determined using an online nutritional analysis software, which primarily relies on the Portuguese Food Composition Table [16]. When specific ingredients were not available in this database, nutritional information was obtained from the FatSecret platform (2024) [17], using values derived primarily from manufacturers’ nutrition labels and other publicly available food composition data. A nutritional assessment sheet was created for each recipe from the three regions. All nutritional data were subsequently organised into a table using Microsoft Excel® format for further statistical analysis. 2.4. Data Analysis A database was constructed to operationalise the variables under study, including variable coding, description, scoring, and statistical categorisation. Statistical analysis was performed using SPSS® software, version 29.0 (SPSS Inc., Chicago, IL, USA). Results were expressed as mean ± standard deviation (SD). Data normality was assessed using the Shapiro–Wilk test, which indicated that several variables were not normally distributed in at least one region. Therefore, data were logarithmically transformed (log10) to approximate normality. After transformation, the assumptions required for one-way analysis of variance (ANOVA) were reassessed, including normality of distributions and homogeneity of variances (Levene’s test), both of which were confirmed. Comparisons between regions were performed using one-way ANOVA, followed by Tukey’s post hoc test for multiple comparisons. Statistical significance was set at p < 0.05. Additionally, six complete menus were constructed (two per region), representing the combinations with the lowest and highest energy values based on the analysed recipes. These menus were evaluated and compared with reference values for energy and nutrient intake. A daily energy intake of 2000 kcal was considered, in accordance with Regulation (EU) No. 1169/2011 [18], with lunch defined as contributing 30% of total daily energy intake [19,20]. Reference macronutrient distribution was set at 15% protein, 55% carbohydrates, and 30% lipids, based on World Health Organization recommendations [21]. For dietary fibre, the EFSA reference value of 25 g/day was adopted [14]. The upper limit for free sugars was defined according to World Health Organization guidelines [22], which recommend that free sugars should not exceed 10% of total daily energy intake. Saturated fatty acids (SFA) were assessed in accordance with EFSA guidance [14], which recommends that their contribution should not exceed 10% of total daily energy intake. Based on these criteria, the following reference values were defined for lunch: 600 kcal energy, 22.5 g protein, 82.5 g carbohydrates, 20 g lipids, 60 g sugars, 7.5 g dietary fibre, 6.7 g SFA, and 600 mg sodium. Results were expressed as percentages of adequacy relative to these reference values, allowing assessment of the degree of compliance of regional menus with current nutritional recommendations. This approach enabled an integrated evaluation of the nutritional quality of traditional Portuguese recipes, both in absolute terms (nutritional composition per 100 g) and relative terms (adequacy in relation to international guidelines). 3. Results and Discussion The results revealed significant nutritional differences among traditional Portuguese first courses from the North, Centre, and South regions (Table 2), reflecting regional variability in ingredients and cooking methods. Comparative analysis identified significant variations in energy value, macronutrient distribution, dietary fibre, sugars, and sodium content, highlighting distinct regional patterns. Region - Recipe Code - Recipe Name North First Course 1 Caldo-Verde North First Course 2 Folar Transmontano North First Course 3 Bolinhos de bacalhau North First Course 4 Bola de carne North First Course 5 Rancho North First Course 6 Sopa Seca à Moda do Minho North Main Course 1 Rojões à moda do Minho North Main Course 2 Arroz de pato à moda de Braga North Main Course 3 Lombo de porco assado North Main Couse 4 Papas de sarrabulho à moda de Sandim do Douro North Main Course 5 Bacalhau à Gomes de Sá North Main Course 6 Bacalhau à Zé do pipo North Main Course 7 Arroz de Lampreia North Main Course 8 Polvo assado na brasa North Dessert 1 Sarrabulho doce North Dessert 2 Rosquilhas North Dessert 3 Pastéis de Santa Clara North Dessert 4 Pão de ló North Dessert 5 Toucinho-do-céu North Dessert 6 Jesuítas Center First Course 1 Sopa de entulho Center First Course 2 Salada de feijão frade Center First Course 3 Peixinhos da horta Center First Course 4 Pipis Center First Course 5 Sopa de Pedra Center First Course 6 Pataniscas de bacalhau Center Main Course 1 Feijoada à Portuguesa Center Main Course 2 Cabrito assado Center Main Course 3 Bife à café Center Main Course 4 Cozido à portuguesa Center Main Course 5 Bacalhau à Brás Center Main Course 6 Bacalhau assado com broa Center Main Course 7 Lampreia Caseira Center Main Course 8 Caldeirada rica Center Dessert 1 Arroz doce saloio Center Dessert 2 Farófias Center Dessert 3 Areias Center Dessert 4 Tigeladas Center Dessert 5 Ovos-moles de Aveiro Center Dessert 6 Carólos South First Course 1 Gaspacho South First Course 2 Sopa de cação South First Course 3 Sopa de Lingueirão South First Course 4 Choquinhos fritos com tinta South First Course 5 Conquilhas à Algarvia South First Course 6 Espargos bravos com ovos South Main Course 1 Carne de porco com amêijoas South Main Course 2 Ovos escalfados com ervilhas South Main Course 3 Pezinhos de Porco de Coentrada South Main Course 4 Entrecosto frito com migas à Alentejana South Main Course 5 Bifes de atum em cebolada South Main Course 6 Carapaus Alimados South Main Course 7 Lulas cheias South Main Course 8 Arroz de berbigão South Dessert 1 Pudim de água South Dessert 2 Morgado de figo South Dessert 3 Tarte de claras ou colchão de noiva South Dessert 4 Bolo mimoso South Dessert 5 Bolos de D. Rodrigo South Dessert 6 Queijinhos de amêndo. Regarding energy value per 100 g, first courses from the Northern region presented the highest mean values (≈202 ± 21 kcal), followed by those from the Southern (≈133 ± 18 kcal) and Central regions (≈126 ± 26 kcal). This difference is primarily attributable to the higher energy density of Northern preparations, which tend to have lower water content and higher proportions of starchy foods, protein, and fat. Representative examples include Caldo Verde (potato and chorizo soup), Bolinhos de Bacalhau (codfish cakesthat absorb oil during frying), Bola de Carne (a bread-based preparation with cured meats), and Rancho (a dish combining pasta, veal, and cured pork products). In the Centre, lower energy density is associated with the predominance of soups and vegetable-based dishes, such as Sopa de Pedra and Sopa de Entulho, despite the inclusion of some fried items, including Peixinhos da Horta. In the South, intermediate energy values reflect the frequent consumption of fish- and shellfish-based soups, such as Sopa de Cação and Sopa de Lingueirão, as well as first courses prepared with moderate amounts of olive oil, such as Conquilhas à Algarvia. With respect to protein content, the highest mean values were observed in the Southern region (≈12 ± 1.9 g), followed by the North (≈11 ± 1.6 g) and the Centre (≈6 ± 1.4 g). The predominance of fish, shellfish, and eggs (foods of high biological value) in Southern first courses explains these findings, as illustrated by preparations such as Espargos Bravos com Ovos. In the North, protein intake is mainly derived from meats and cured products, such as Folar Transmontano and Bola de Carne, as well as from fish-based preparations like Bolinhos de Bacalhau. In the Centre, lower protein density is associated with a higher proportion of broths, vegetables, and legumes, which dilute protein content per 100 g, although some dishes still include meat, fish, or cured meats. Carbohydrate content was highest in the North, followed by the Centre and the South, reflecting the frequent use of potatoes, bread, and flour in Northern recipes. In the Centre, intermediate values are associated with the inclusion of legumes and cereals in soups and salads, whereas in the South, lower carbohydrate content reflects a greater emphasis on fish and vegetables and a reduced contribution from starchy ingredients. Sugar content was low and similar across regions (≈1–2 g), corresponding mainly to naturally occurring sugars in vegetables, such as onions. Differences in dietary fibre content were modest, although the Centre showed slightly higher values, associated with the frequent use of legumes and vegetables in dishes such as Sopa de Pedra, Sopa de Entulho, and Salada de Feijão-Frade. Regarding total fat, the highest mean values were observed in the Centre (≈14 ± 1.5 g), largely attributable to the predominance of fried preparations such as Peixinhos da Horta and Pataniscas de Bacalhau, followed by the North (≈11 ± 1.4 g) and the South (≈6 ± 2.6 g). In the North, fat content is mainly derived from meats and cured products (e.g., chorizo, prosciutto, ham and other cured meats), whereas in the South, olive oil constitutes the primary lipid source and is generally used in moderate amounts, often combined with lean fish and shellfish. The profile of SFA followed a similar trend, with higher values in the North and Centre due to the greater use of animal-based ingredients rich in saturated fat. Sodium content was markedly higher in the North (≈482 ± 91.8 mg), reflecting the frequent use of salted and cured meats in first-course preparations, such as Caldo Verde, Folar Transmontano, Bola de Carne, Rancho, and Sopa Seca à Moda do Minho. In contrast, sodium levels in the Centre (≈ 37 ± 57 mg) and the South (≈136 ± 37 mg) were substantially lower, consistent with the reduced use of processed meats and the predominance of vegetable and fish-based preparations. In summary, the Northern region was characterised by higher energy density, higher carbohydrate content, and elevated sodium levels, reflecting the frequent use of starchy ingredients, meats, and cured products in less diluted preparations. The Central region exhibited higher total fat values, largely resulting from the prevalence of fried dishes, whereas the Southern region showed a more balanced nutritional profile, with higher protein content and a predominance of unsaturated fats derived from olive oil and fish. Mean SFA content was higher in the North region compared to the Centre and South regions. Sugar content remained low and homogeneous across regions, while dietary fibre showed only minor variation, with a slight advantage observed in the Centre. The analysis of the average nutritional composition of main courses from the North, Centre, and South regions (Table 3) revealed regional differences associated with ingredient selection, relative proportions of meat, fish, and vegetables, and the cooking techniques characteristic of each area of the country. Main courses from the Northern region presented the highest mean energy value (≈207 ± 22.8 kcal), followed by those from the Southern (≈179 ± 63.9 kcal) and Central regions (≈173 ± 22.3 kcal). This pattern reflects the predominant types of preparations characteristic of each region. In the North, dishes such as Rojões à Moda do Minho, Arroz de Pato à Moda de Braga, and Papas de Sarrabulho à Moda de Sandim do Douro stand out due to the use of fatty meats and high proportions of starchy ingredients. Variations of Bacalhau à Gomes de Sá and Bacalhau à Zé do Pipo also exhibit high energy density because of the use of olive oil, mayonnaise, and potatoes. In the Centre, lower energy values are associated with more balanced and diversified dishes that combine nutrient-dense ingredients with components rich in water and vegetables, thereby reducing energy content per 100 g. Preparations such as Cozido à Portuguesa and Feijoada à Portuguesa include meats, cured products, and legumes, but also large amounts of vegetables, potatoes, and broth. Similarly, Caldeirada Rica and Lampreia Caseira incorporate lean fish, tomato, and onion, resulting in more voluminous dishes with lower fat concentration. In the South, intermediate energy values reflect a balance between richer meat-based dishes, such as Entrecosto Frito com Migas and Pezinhos de Porco de Coentrada, and lighter fishand seafood-based recipes, including Arroz de Berbigão and Carapaus Alimados. Protein content was highest in the Southern region (≈13 ± 7.0 g), followed by the North (≈12 ± 2.0 g) and the Centre (≈11 ± 1.0 g). In the South, fish- and seafood-based dishes predominate, such as Bifes de Atum em Cebolada, Arroz de Berbigão, and Lulas Cheias, providing high biological value protein with relatively low saturated fat content. In the North, protein levels are also elevated due to the frequent use of meat and codfish in dishes such as Arroz de Pato à Moda de Braga, Bacalhau à Gomes de Sá, and Bacalhau à Zé do Pipo. In the Centre, lower protein density per 100 g results from the combination of meat or fish with larger quantities of vegetables, rice, or potatoes. Carbohydrate content was broadly similar across regions, with a slight upward trend in the North and Centre. In the Centre, dishes such as Bacalhau à Brás, Bacalhau com Broa, and Arroz de Lampreia contribute substantial amounts of starchy foods. In the North, carbohydrate levels are explained by the frequent use of rice, potatoes, and pasta, whereas in the South, slightly lower values were observed, although dishes such as Arroz de Berbigão, Migas à Alentejana, and Carapaus Alimados also contribute to total carbohydrate intake. Sugar content was low and similar across regions, as expected for savoury main courses. Values for dietary fibre were very similar among regions (≈1 g), with no relevant differences. This uniformity reflects the widespread inclusion of fibre-rich plant-based foods, such as legumes, vegetables, and cereals, across all regions. Regarding total fat, the highest mean values were observed in the North (≈14 ± 2.2 g), followed by the South (≈11 ± 3.9 g) and the Centre (≈10 ± 2.1 g). In the North, higher fat content results from the use of pork, cured meats, sausages, and lard, as well as the frequent addition of olive oil, as seen in Papas de Sarrabulho, Rojões à Moda do Minho, and Arroz de Pato à Moda de Braga. In the South, fats are predominantly of plant origin, mainly olive oil, which is widely used in regional cuisine. In the Centre, although fat is added, the predominance of broth-based dishes contributes to a lower average lipid density. The SFA profile was similar across regions, reflecting the combined use of olive oil and fish as major fat sources. Sodium content was relatively homogeneous, ranging from approximately 240 to 270 mg, with slightly higher mean values observed in the Centre (≈272 ± 145 mg), followed by the South (≈269 ± 116 mg) and the North (≈243 ± 126 mg). In the Centre, higher sodium values are associated with the use of sausages, salted meats, and codfish. In the North, although salted ingredients are common, sodium concentration may be partially diluted in preparations with higher oil or milk content. In the South, intermediate sodium values are related to the use of molluscs and shellfish naturally rich in sodium, such as in Arroz de Berbigão and Carne de Porco com Amêijoas, as well as moderate use of condiments. Overall, the Northern region stood out for higher energy density and lipid content, reflecting the frequent use of fatty meats, cured products, and culinary fats. The Southern region presented a more favourable lipid profile due to the predominance of unsaturated fats from olive oil and fish. The Central region showed lower energy and lipid density but slightly higher sodium levels, resulting from the combined use of salted meats, sausages, and codfish. Differences in SFA, protein, carbohydrates, and dietary fibre were minimal, suggesting that, regardless of region, traditional Portuguese main courses maintain a relatively balanced nutritional profile for these parameters. The analysis of the average nutritional composition of traditional Portuguese desserts from the North, Centre, and South regions (Table 4) revealed relatively small differences in energy density and macronutrient distribution, largely associated with the choice and proportion of key ingredients, namely sugar, eggs, flour, nuts, and fats. Desserts from the Northern region showed the highest mean energy value (≈385 ± 28.1 kcal), followed by those from the South (≈375 ± 30.4 kcal) and the Centre (≈374 ± 80.7 kcal). This pattern reflects the predominant use of sugar, almonds, egg yolks, and added fats in dense preparations with low water content. In the North, desserts such as Toucinho-do-Céu (500 g sugar, 250 g almonds, and 50 g butter) and Jesuítas (puff pastry with butter and an egg white–sugar filling) contribute substantially to energy density. Other examples, including Pão de Ló and Pastéis de Santa Clara, which are rich in sugar and egg yolks, further reinforce this trend. In the Central region, although desserts such as Tigeladas and Ovos Moles de Aveiro are also energy-dense, the inclusion of lighter preparations, such as Carólos, contributes to a lower regional average. In the Southern region, intermediate energy values result from a balance between highly energetic desserts, such as Morgado de Figo (500 g figs, 500 g sugar, and 500 g almonds), and lighter options, such as Pudim de Água, in which the addition of water slightly reduces overall energy density. Protein content was highest in the South, followed by the North and the Centre, reflecting differences in the number of eggs used in regional dessert recipes. Carbohydrates were the predominant macronutrient in desserts from all regions, although with marked regional variation. The highest carbohydrate content was observed in the South, followed by the North, and the lowest in the Centre. In the South, this pattern is attributable to the extensive use of refined sugar and naturally sweet ingredients, as seen in Morgado de Figo, Bolinhos de D. Rodrigo (1 kg sugar), and Tarte de Claras. In the North, carbohydrate levels are similarly high due to desserts such as Toucinho-do-Céu, Pastéis de Santa Clara, and Pão de Ló, which incorporate large amounts of sucrose and flour. In contrast, the lower carbohydrate content observed in the Centre reflects a more diversified ingredient composition, where sugar— although abundant in desserts such as Arroz Doce Saloio and Ovos Moles de Aveiro—is combined with larger proportions of milk, flour, and eggs, resulting in lower carbohydrate concentration per 100 g. Values for dietary fibre were low across all regions, ranging from 0 to 2 g. The North and South presented values closer to 2 g, mainly due to the inclusion of flour, figs, and nuts. In the Centre, fibre content was nearly negligible, reflecting the predominance of sugar, milk, and eggs in desserts such as Farófias, Ovos Moles de Aveiro, and Arroz Doce Saloio. Regarding total fat, the highest mean values were observed in the Centre (≈23 ± 10.0 g), followed by the North (≈18 ± 3.0 g) and the South (≈13 ± 2.9 g). In the Centre, this pattern is largely driven by desserts rich in added fats, such as Areias, which contain lard; the low water content and high sugar concentration of these preparations limit fat dilution in the final product. In the North, intermediate fat values result from the use of butter and lard in puff pastry and traditional cakes, such as Jesuítas and Rosquilhas. In the South, lower total fat content reflects the use of smaller amounts of added fats, with a greater contribution from natural lipid sources, such as olive oil and almonds. Although these ingredients contribute to overall energy value, they provide a more favourable lipid profile. The SFA content followed the sequence North (≈6 g) > Centre (≈4 g) > South (≈2 g), reflecting the greater use of animal fats in Northern and Central desserts and the predominance of unsaturated fats from olive oil and almonds in Southern preparations. Sodium content was very low across all regions, with slightly lower values observed in the South (≈37 mg), followed by the Centre (≈41 mg) and the North (≈73 mg). As expected, salt is not a relevant ingredient in desserts, and the minor variations observed are attributable to raw materials such as eggs and butter or to differences in preparation processes. Overall, the Northern region stood out for higher energy density and saturated fat content, with intermediate total lipid values. The Central region exhibited the highest total fat content, intermediate SFA levels, and the lowest dietary fibre content. The Southern region showed higher protein, carbohydrate, and sugar contents but lower total fat and SFA levels, while maintaining residual sodium values. These results reflect regional pastry traditions and ingredient matrices, particularly the relative proportions of eggs, sugar, added fats, flour, and nuts that characterise traditional Portuguese desserts. To determine whether the descriptive differences observed between regions were statistically significant, an inferential comparison of the mean nutritional values of the three regions was performed (Table 5). This analysis aimed to identify which nutritional parameters of traditional Portuguese recipes differed significantly between the North, Centre, and South regions. Statistically significant regional differences were observed only for first-course dishes. For energy value, a significant difference was identified between the North (202 ± 21 kcal) and the Centre (126 ± 26 kcal) (p < 0.05), whereas values for the South (133 ± 18 kcal) did not differ significantly from either region. Regarding dietary fibre, a significant difference was observed between the Centre (2.0 ± 0.5 g) and the South (1.0 ± 0.3 g), with the Centre showing the highest mean value. With respect to sodium, the North (482 ± 91.8 mg) differed significantly from both the Centre (137 ± 57.2 mg) and the South (136 ± 37.3 mg), presenting markedly higher sodium content. No statistically significant regional differences were observed for protein, carbohydrates, sugars, total fat, or SFA in first-course dishes (p > 0.05). Furthermore, for main courses and desserts, no statistically significant differences were identified for any of the evaluated nutritional parameters (p > 0.05). Although descriptive variability was observed between regions, these differences were insufficient to reach statistical significance, suggesting a broadly similar nutritional composition of main courses and desserts across the three regions. A comparison was also conducted between the nutritional values of the most and least energy-dense complete menus from the North, Centre, and South regions, with the aim of assessing their adequacy relative to established nutritional recommendations for a complete meal. This analysis, summarised in Table 6, complements the previous inferential evaluation by providing an applied perspective on the nutritional impact of traditional dishes when combined into representative regional menus. The menus were constructed based on the recipes previously analysed, integrating a first course, a main course, and a dessert from each region to reflect the typical structure of a complete meal. This approach allowed assessment of the extent to which combinations of traditional dishes align with, or deviate from, reference values for a balanced meal, thereby identifying potential nutritional excesses or deficits and highlighting regional differences in Portuguese dietary patterns. The complete menus analysed in this study represent theoretical combinations based on standardised nutritional values per 100 g of each recipe. These combinations were not intended to replicate actual portion sizes or real consumption patterns, but rather to provide a comparative framework for evaluating the nutritional balance of traditional dishes when combined into a complete meal. Nutritional adequacy of the complete menus was assessed using the Comparison with Reference Value (CRV), which expresses each nutritional parameter as a percentage of the reference value established for a complete meal. Values between 90–110% were considered adequate for energy and macronutrients. For sugars, SFA, and sodium, values exceeding the reference were classified as excessive, whereas for dietary fibre, values below 90% of the reference were considered insufficient.... https://www.mdpi.com/2072-6643/18/15/2486