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Abstract: The young stems of Opuntia spp., known as cladodes are widely consumed in Mexico, and appreciated for their high content of fiber and beneficial effects in the metabolism of glucose. Since, boiling process is often applied to these vegetables, the objective of this study was to evaluate the influence of this process on the chemical composition, antioxidant capacity and physicochemical properties of two cladode cultivars. The components most affected were the soluble compounds (sugars, minerals, vitamin C and phenolics), while proteins, lipids and fiber showed a high retention. The losses of phytochemicals were related to the decrease of the antioxidant capacity. Cladodes presented good hydration properties inducing a non-Newtonian, pseudoplastic and thixotropic behavior in suspension. Heat treatment reduced the viscosity and gel consistency and these changes affected the physiological properties related to capacity of cladodes to hold glucose and control the glycemic response. The intake of these compounds and the estimation of some properties may be overestimated when data of raw sources are used. Further research to determine boiling conditions to minimize the changes on composition of these vegetables is necessary. [Copyright &y& Elsevier]

Abstract: The genus Opuntia embraces different species of cactus, and many of them produce acid fruits known as xoconostle, which are considered valuable vegetable foods in Latin America. Xoconostle fruit contains an edible thick-acid-freshly mesocarp, and seeds that are considered as by-products. Given the high potential of its use and consumption, and the lack of information about its detailed chemical composition and bioactive compounds, the aim of this study was to evaluate the nutritional and antioxidant properties of pulp and seeds of two highly consumed commercial cultivars of xoconostle fruits (Opuntia joconostle F.A.C. Weber ex Diguet, cv. Cuaresmeño, and Opuntia matudae Scheinvar, cv. Rosa). This investigation shows that the pulp of the studied xoconostle cultivars had an appreciable amount of soluble fiber and antioxidant compounds such as ascorbic acid, while the seeds are a source of fiber, phenolics, flavonoids, PUFAs and tocopherols (specially γ-tocopherol), which provide a good antioxidant capacity. In the light of these results, xoconostle fruits should be considered of great interest for either promoting the conventional consumption, and also as sources of bioactive compounds for the addition to other food products, so that all the nutrients present are fully used, instead of being discarded. [Copyright &y& Elsevier]

There is a lack of information on the potential use of xoconostle cultivars as sources of antioxidants for food, pharmaceutical and colorant industries. The aim of this study was to provide a phytochemical characterisation and antioxidant activity evaluation of Opuntia matudae Scheinvar cv. Rosa by-products (epicarp and endocarp mucilage’s), in order to evaluate their interest as sources of functional ingredients for human or animal foods. These by-products showed a high content in glucose, citric and linoleic acids, tocopherols, and isorhamnetin- O -(di-deoxyhexosyl-hexoside) (mainly in epicarp), and presented relevant antioxidant properties. The obtained results support the use of O. matudae Scheinvar cv. Rosa agro-industrial by-products as functional food ingredients, namely for antioxidant-enriched formulations, instead of being discarded. [ABSTRACT FROM AUTHOR]

Abstract: Cactus pear (Opuntia ficus-indica) fruit is a berry with a tasty pulp full of seeds that constitutes about 10–15% of the edible pulp. In Mexico, cactus pear is mainly consumed fresh, but also has the potential to be processed in other products such as juice. The objective of this study was to evaluate the effect of different ultrasound conditions at amplitude levels ranging (40% and 60% for 10, 15, 25min; 80% for 3, 5, 8, 10, 15 and 25min) on the characteristics of purple cactus pear juice. The evaluated parameters were related with the quality (stability, °Brix, pH), microbial growth, total phenolic compounds, ascorbic acid and antioxidant activity (ABTS, DPPH and % chelating activity) of purple cactus pear juices. The ultrasound treatment for time period of 15 and 25min significantly reduced the microbial count in 15 and 25min, without affecting the juice quality and its antioxidant properties. Juice treated at 80% of amplitude level showed an increased of antioxidant compounds. Our results demonstrated that sonication is a suitable technique for cactus pear processing. This technology allows the achievement of juice safety and quality standards without compromising the retention of antioxidant compounds. [Copyright &y& Elsevier]