Use of Almond Skins to Improve Nutritional and Functional Properties of Biscuits: An Example of Upcycling

Abstract

Upcycling food industry by-products has become a topic of interest within the framework of the circular economy, to minimize environmental impact and the waste of resources. This research aimed at verifying the effectiveness of using almond skins, a by-product of the confectionery industry, in the preparation of functional biscuits with improved nutritional properties. Almond skins were added at 10 g/100 g (AS10) and 20 g/100 g (AS20) to a wheat flour basis. The protein content was not influenced, whereas lipids and dietary fiber significantly increased (p < 0.05), the latter meeting the requirements for applying “source of fiber” and “high in fiber” claims to AS10 and AS20 biscuits, respectively. The addition of almond skins altered biscuit color, lowering L* and b* and increasing a*, but improved friability. The biscuits showed sensory differences in color, odor and textural descriptors. The total sum of single phenolic compounds, determined by HPLC, was higher (p < 0.05) in AS10 (97.84 µg/g) and AS20 (132.18 µg/g) than in control (73.97 µg/g). The antioxidant activity showed the same trend as the phenolic. The p-hydroxy benzoic and protocatechuic acids showed the largest increase. The suggested strategy is a practical example of upcycling when preparing a health-oriented food product.

Optimization of the Formulation of Rice Biscuits Supplemented with D. Edulis (L.) Powder Using Response Surface Methodology

“…However, its conditions of cultivation associated to the high cost of its importation as well as the phenomenon of gluten intolerance have led to the development of several researches in order to find alternatives to wheat. Nowadays, researches are directed towards the use of local raw materials due to their composition which will improve the nutritional composition of biscuits and also to their great potential for improving the sustainability of food systems [ 5 ]. In this light, the promotion of the use of composite flours, which integrate flours derived from local crops (cereals, tubers, roots, and leguminous seeds), in bakery products such as biscuits is being encouraged.…”

“…Besides rice, other local ingredients for which a growing attention is paid nowadays in biscuit formulation are those rich in health-promoting compounds. Pasqualone et al [ 5 ] demonstrated the use of almond skins rich in bioactive compounds in the formulation of nutritious and functional biscuits. Safou ( D. edulis (L.)) a highly perishable local food [ 11 ] stands as an example of those ingredients which can be valorized in the preparation of functional biscuits for improving its sustainability.…”

Almond (Prunus dulcis cv. Casteltermini) Skin Confectionery By-Products: New Opportunity for the Development of a Functional Blackberry (Rubus ulmifolius Schott) Jam

“…Similarly, the addition of almond skin (at 10 g/100 g and 20 g/100 g) to a wheat flour basis for biscuit preparation indicated an increase in antioxidant potential [ 53 ].…”

Can a structured emulsion (fat in water‐fibre system) substitute saturated fat in cookies without hampering their quality?

“…Nutritional properties of cookies can be enhanced throughout fortification using additional health-beneficial ingredients (e.g. protein isolates and fibre) (Jan et al, 2018;Pasqualone et al, 2020;Boukid, Rosell, & Castellari, 2021) or replacement of the basic ingredients (wheat flour, sugar and fat) by healthier alternatives such as protein-rich flours (e.g. pulses flours), low-calorie sweeteners and rich unsaturated fats (Aggarwal, Sabikhi, & Sathish Kumar, 2016;Thongram et al, 2016;Curti et al, 2018;Xu et al, 2020).…”