Utilization of Flours Derived from the Waste from the Frozen Vegetable Industry for Bakery Product Production

Currently, the agri-food industry faces a significant challenge in reducing food waste in line with circular economy principles. In this context, the frozen vegetables industry rejects products that do not meet consumers’ appearance standards, leading to a waste of vegetables that could be reincorporated into the food chain. Thus, waste generated from broccoli, cauliflower, and peas in the last selection stages of a frozen vegetable industry manufacturer were collected, dehydrated, and transformed into flour. These flours were used to replace 50% of the wheat flour in a basic bakery product, using a baked dough made only with flour and water, and analyzed from physical, nutritional, and sensory perspectives. The doughs showed slight changes in texture, with increased hardness values and reduced cohesiveness, making them more difficult to handle, as well as changes in color due to the incorporation of vegetable pigments. However, from a nutritional perspective, these products were enriched in protein, with values that reached up to 20.88% in the sample made with broccoli flour, and dietary fiber, with an increase from 0.67% obtained in the control sample to 6.00% in the sample made with pea flour and to over 8 in the samples made with broccoli and cauliflower. This was accompanied by a reduction in total carbohydrates, leading to similar energy values (around 380 kcal/100 g dm). Furthermore, the content in total phenolic compounds and antioxidant activity were increased, especially when flours from the Brassica species were used. From the sensory point of view, all the samples made with vegetable flours received positive evaluations, even higher than the control sample when smell or taste was evaluated. In this regard, the samples made with cauliflower flour stood out when the taste was evaluated, reaching values above three on a scale where the maximum value was four. All of these results demonstrate that using these wasted vegetables can be a good alternative for improving the nutritional properties of basic bakery products.