# Antioxidant Properties of Wafers with Added Pumpkin Seed Flour Subjected to In Vitro Digestion
###### Abstract  
In this study, our research aim was to assess the influence of pumpkin seed flour addition on the antioxidant properties, consumer acceptability, functional properties, and texture of wafers. The in vitro gastrointestinal digestion process was used to assess the effectiveness of fortification in terms of the potential bioavailability of phenolic compounds and peptides. The antioxidant activity of the obtained hydrolysates and potentially bioavailable fractions (\(\leq\)3.5 kDa) was tested. The highest antiradical activity and Fe\({}^{2+}\) chelation ability (IC\({}_{50}\)) were noted for the fraction obtained from wafers with the greatest addition of pumpkin seed flour--Pf4 (0.49 mg/mL for ABTS\({}^{**}\), 3.84 mg/mL for DPPH\({}^{*}\), and 2.04 mg/mL for Fe\({}^{2+}\) chelation). The addition of pumpkin seed flour caused the color of the wafers to change to a darker one (24.46% differences in L\({}^{*}\) between C and P4), which influenced consumer ratings. This study shows that adding pumpkin seed flour increases the peptide and phenolic contents of wafers (1.13 mg/mL and 1.01 mg/mL of peptides and 0.429 mg/mL and 0.351 mg/mL of phenolics for P4 and C hydrolysates, respectively) and enhances their antioxidant activity, with only minimal effects on taste, aroma, crispness, water and fat adsorption capacity, and foaming ability. Fractions \(\leq\) 3.5 kDa showed greater antioxidative activity than hydrolysates, and the addition of pumpkin seed flour improved these properties. To sum up, pumpkin seeds are a valuable source of antioxidant compounds (phenolic compounds and peptides) and can be used to enrich various products. pumkkin seeds; wafers; phenolics; peptides; antioxidant; functional food +
Footnote †: journal: Medical Image and Vision  
of omega-3 and omega-6, which have benefits for both the heart and the liver. Research also suggests that omega-3 in pumpkin seeds can decrease the risk of thrombosis and arrhythmias [8]. Pumpkin seeds are also a valuable source of biologically active compounds, such as phenolic acids (vanillic, sinapic, p-hydroxybenzoic, caffe, ferulic, p-coumaric), carotenoids, tocopherols, glycosides, and sterols [9]. [PERSON] et al. showed a higher content of total phenols and total flavonoids in pumpkin seeds compared to the peel and pulp, and, consequently, higher antioxidant activity [10]. The pumpkin seed proteins are a source of bioactive peptides, i.e., short amino acid chains with various health benefits. These peptides are known for their potential to exert physiological effects beyond basic nutrition. Some bioactive peptides from pumpkin seeds may have antioxidant, antimicrobial, antihypertensive, anticancer, anti-inflammatory, or other health-promoting properties [11; 10; 12]. They have various physiological activities based on specific amino acid sequences. Bioactive peptides could be released from proteins during digestion, food processing or enzymatic hydrolysis in vitro, autolysis, and microbial fermentation. Several studies have investigated the bioactive peptides derived from pumpkin seeds and their effects on various health conditions [13; 14]. Incorporating pumpkin seeds into the diet can provide these bioactive peptides and other essential and biologically active components, making them a valuable addition to a balanced diet. Whole pumpkin seed flour is nutrient-dense and contains proteins, fiber, unsaturated fatty acids, phytosterols, vitamins, and minerals [9; 10]. Pumpkin seed flour has been incorporated in several baked products by replacing wheat flour in biscuits [15], muffins [16], and cookies [17]. Wafers are one of the most popular and important bakery items because they have a low moisture content and a long shelf life, and they are rich in energy but lack the phytonutrients with health benefits [18; 19]. In contexts such as this one, enriching food products with valuable and innovative ingredients is a key strategy for filling nutritional gaps, preventing chronic diseases, and promoting overall health [4].