Reformulation of bakery products: from functional ingredients development to in vitro gastrointestinal digestion

Abstract

Bakery products are widely consumed due to their appealing characteristics and can be sources of some nutrients, but the excessive consumption of some of them is related to detrimental effects on human health. Fat content is one of the greatest concerns in this type of products, both by their quantity and quality. In addition to it, the demand includes healthier, good quality and more sustainably produced foodstuffs. Therefore, efforts towards the search of new ingredients and the development of new reformulation strategies to improve or reduce the amount of fat and, as an added benefit, incorporate bioactive compounds has been addressed by the industry and the research community. The development of functional ingredients based on different vegetable oils, to serve as butter replacers in bakery products is summarized in this work. Five vegetable oils were characterized, of which echium, hemp and flax oil showed a high content of polyunsaturated fatty acids, especially omega-3 fatty acids, while moringa oil and extra virgin olive oil were rich in oleic acid. All of the analyzed oils had important content of plant sterols. Two functional ingredients were designed and developed as fat substitutes in bakery products (emulsion and gelled emulsions) with a lipid profile rich in unsaturated fats, lower energy value (compared to butter) and containing bioactive compounds. Both functional ingredients were used in the reformulation of Muffins and Cookies, obtaining successful results from the nutritional point of view, improving their composition and being able to bear nutrition claims related to total fat content, energy value, omega-3 fatty acids and fiber content. In addition to nutritional improvements, the developed products showed sensory characteristics similar, in general, to products with traditional formulation. The in vitro gastrointestinal digestion assays to which the developed products (gelled emulsions and cookies) were subjected, showed that fat distribution and composition between bioaccessible phase and residual phase varied according to the nature of the lipid fraction digested. The content of bioactive compounds was highly decreased after in vitro gastrointestinal digestion. And finally, the use of antioxidants could have a positive effect in preserving the bioactive compounds in the formulations and decrease the extent of lipid oxidation.