Comparative analysis of the chemical composition of different portuguese bread

Bakery products are one of the most widely consumed foods in the world. Among them, bread is daily consumed by all social classes due to its macro (carbohydrates, protein, and fat) and micronutrients (minerals and vitamins). However, the refined wheat used in traditional baking diminishes its nutritional quality by reducing its dietary fibre, vitamins, minerals, and phytochemicals1. In addition, studies have been showing some health-related problems associated with obesity and diabetes. Compared with others made with different cereals or whole grains, traditional bread tends to be less satiating and increase the postprandial glycaemic index2. Thus, the great challenge of the cereal industry today is to innovate and reinvent a large part of its products, mainly by changing the traditional composition of food products, since it seems to be an effective method to improve the diet. Alternatives such as whole grains, other cereals or the incorporation of protein-rich flours such as legumes may help improve the nutritional quality of bread and have a favourable impact on consumers’ health3. Thus, in this study, a comparative analysis, and chemical parameters among two traditional wheat bread (smoked sausage and cheese, SSCB; and wine, WB) and five non-conventional bread supplemented with different cereals (rye, RB; legumes and cereals, LCB; biological seed, BSeB; biological spelt, BSpB; and chickpea and sprouted seeds, CSSB) was performed. The bread centesimal composition was evaluated by AOAC official procedures; free sugars using HPLC-RI, and fatty acids by GC-FID. Regarding the chemical characterisation of traditional bread, SSCB showed a high protein concentration (9.95±0.02 g 100g-1 FW). However, it was also the bread with the highest amount of fat and a high percentage of saturated fatty acids (6.1±0.1 g 100g-1 FW and 67.1±0.4 %, respectively). WB revealed the highest concentration of free sugars (37.6±1.8 g 100g-1 FW). In general, the non-conventional bread presented lower energy and higher polyunsaturated fatty acids than the traditional. Additionally, RB, BSpB, and CSSB presented the lowest fat concentration, with CSSB showing the highest concentration of dietary fibre (7.2±0.4 g 100g-1 FW). This study demonstrates that incorporating alternative flours produces bread of higher nutritional quality. In general, non-conventional bread is lower in calories, fat and have a higher percentage of polyunsaturated fatty acids and dietary fibre.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020); national funding by F.C.T. and P.I., through the institutional scientific employment program-contract for L. Barros contracts. The authors are also grateful to FEDER-Interreg España-Portugal programme for financial support through the project TRANSCoLAB 0612_TRANS_CO_LAB_2_P. Manuel Ayuso is grateful to the LOCALNUTLEG project (PRIMA programme, Call 2020, Section 1 2021 Agrofood Value Chain topic 1.3.1.) for his postdoctoral research grant.