Wild Fruits of Crataegus monogyna Jacq. and Sorbus aria (L.) Crantz: From Traditional Foods to Innovative Sources of Pigments and Antioxidant Ingredients for Food Products.

Hawthorn (Crataegus monogyna Jacq.) and whitebeam (Sorbus aria (L.) Crantz) are wild species traditionally used as ethnic foods in the Mediterranean area. Their red berries, and mainly the peels, may be used as ingredients due to their color (replacing other synthetic colorants) or functional properties. Some previous studies analyze all edible fruits, but there is very little literature on the composition and properties of the pulpless epidermis of the fruits of C. monogyna and no literature concerning the fruits of S. aria. Total phenolic compounds (TPC) and families of hydroxybenzoic acids, hydroxycinnamic acids, flavonols, and total monomeric anthocyanins were determined in the epidermis of C. monogyna and S. aria fruits. The in vitro antioxidant capacity was also determined using QUENCHER (Quick-Easy-New-CHEap-Reproducible) methodology. Anthocyanins profiles were analyzed in hydroalcoholic extracts through HPLC/MS. C. monogyna fruits presented higher content of TPC than S. aria, with hydroxybenzoic acids (2870.6 mg GAE/100g dw) as the major family, followed by flavonols (771.4 mg QE/100 g dw) and hydroxycinnamic acids (610.3 FAE/100 g dw). Anthocyanins were found in 251.7 mg cyanidin-3-glucoside/100 g dw, characterized by the content of cyanidin-O-hexoxide and peonidin-O-hexoxide. The levels of these compounds correlated with higher values of a* parameter (higher intensity of reddish color). These fruits also showed higher antioxidant capacity by Q-Folin-Ciocalteu and Q-FRAP. S. aria peels had fewer phenolic compounds, particularly anthocyanins (33.7 mg cyanidin-3-glucoside/100 g dw), containing different cyanidin derivatives. From these results, new insights about the composition of the epidermis of these wild fruits are provided, and their potential as ingredients for the food industry is corroborated.

Dwarf Kiwi (Actinidia arguta Miq.), a Source of Antioxidants for a Healthy and Sustainable Diet.

The feasibility of using dwarf kiwi fruits (Actinia arguta Miq.) as a healthy and sustainable food, compared to other types of commercial kiwi fruits, was evaluated in the present study. The overall antioxidant capacity of these fruits was assessed by either extraction-dependent methods (ABTS, ORAC) or the direct method called Quick, Easy, New, CHEap, Reproducible (QUENCHER) (DPPH, FRAP, Folin-Ciocalteu), applied for the first time to analyze kiwi fruits. With this methodology, all the molecules with antioxidant capacity are measured together in a single step, even those with high molecular weight or poor solubility in aqueous extraction systems, such as antioxidant dietary fiber. The effect of kiwi extracts on physiological and induced intracellular reactive oxygen species (ROS) production on IEC-6 cells was also analyzed, as well as total phenolic content (TPC) by Fast Blue BB, flavonols, hydroxycinnamic acids, and hydroxybenzoic acids. A. arguta fruits showed the highest values in all the antioxidant assays, being remarkably higher than the other kiwi species for Q-FRAP and Q-DPPH. Dwarf kiwi showed the highest potential in reducing physiological ROS and the highest values of TPC (54.57 mgGAE/g), being hydroxybenzoic acids the main phenolic family found (2.40 mgGAE/g). Therefore, dwarf kiwi fruits are a natural source of antioxidants compared to conventional kiwi fruits, being a sustainable and healthy alternative to diversify fruits in the diet.

Study of Xoconostle (Opuntia spp.) Powder as Source of Dietary Fiber and Antioxidants.

The objective of this study is to evaluate the nutritional composition, antioxidant properties, and functional characteristics of two cultivars of xoconostle Opuntia xoconostle F.A.C. Weber in Diguet cv. Cuaresmeño (XC) and Opuntia matudae Scheinvar cv. Rosa (XR). The samples were frozen (-32 °C, 48 h), lyophilized (96 h, -55 ± 1 °C, vacuum of 0.040 Mbar), and homogenized (size particle 500 µm) to get the xoconostle powder. Both cultivars (XC and XR) had a high content of carbohydrates characterized by soluble sugars (9.8 ± 0.7 and 29.9 ± 0.5 g/100 g dm) and dietary fiber (30.8 ± 0.7 and 36.8 ± 0.9 g/100 g dm), as well as lower proportions of organic acids, mainly citric acid (18.8 ± 0.0 and 13.6 ± 0.0 mg/100 g dm). These samples also had a high content of phenolic compounds (1580.3 ± 33.1 and 1068.5 ± 70.8 mg GAE/100 g dm), vitamin C (723.1 ± 16 and 320.2 ± 7.5 mg/100 g dm), and antioxidant activity ABTS·+ and DPPH· (between 1348.1 ± 74.0 and 3318.7 ± 178.8 µmol TE/100 g dm). Since xoconostle samples had a high content of dietary fiber, they were characterized by the capacity of water retention (water holding capacity 6.00 ± 0.1 and 5.5 ± 0.2 g H2O/g dm) and gel formation (swelling 5.2 ± 0.0 and 5.5 ± 0.0 g H2O/g dm), related with the retention of lipids and glucose in the food matrix similar to other foods. XR was characterized by a higher amount of dietary fiber, sugars and organic acids, while XC had higher phenols content and antioxidant properties, with higher values of functional properties. Then, our data suggest that both xoconostle cultivars in powder can be used as a functional ingredient for its fiber content and antioxidant properties, contributing with sensorial aspects as flavor and color. Therefore, these highly valued products can be used in the pharmaceutical and food industries.