In this study, the potential use of Moringa oleifera as a clotting agent of different types of milk (whole, skim, and soy milk) was investigated. M. oleifera seed extract showed high milk-clotting activity followed by flower extract. Specific clotting activity of seed extract was 200 times higher than that of flower extract. Seed extract is composed by four main protein bands (43.6, 32.2, 19.4, and 16.3 kDa). Caseinolytic activity assessed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and tyrosine quantification, showed a high extent of casein degradation using M. oleifera seed extract. Milk soy cheese was soft and creamy, while skim milk cheese was hard and crumbly. According to these results, it is concluded that seed extract of M. oleifera generates suitable milk clotting activity for cheesemaking. To our knowledge, this study is the first to report comparative data of M. oleifera milk clotting activity between different types of soy milk.

Opuntia spp. plants occupy an important socioeconomic role in arid and semiarid zones where water is scarce. Irrigation increases the productivity of these plants; however, its effect on the yield, composition, and physicochemical properties of the mucilage is unknown. Three irrigation regimens were tested: non-irrigated (rainwater), supplemental irrigation (irrigation between field capacity (0.28 m³ m⁻³) and permanent wilting point (0.14 m³ m⁻³)), and full irrigation (100% of crop evapotranspiration), on the four cactus pear varieties (‘Amarilla Olorosa’ (Opuntia spp.), ‘Cristalina’ (Opuntia albicarpa Scheinvar), ‘Dalia Roja’ (Opuntia spp.), and ‘Roja Lisa’ (O. ficus-indica (L.) Mill)). Irrigation regimens were applied during the dry season (March to June in the northern hemisphere). Composite samples of cladodes per replicate and treatment were collected for mucilage extraction. The mucilage was characterized for yield, color, chemical composition, infrared spectroscopy, viscosity, and molar mass. The combination with the greatest yield was ‘Amarilla Olorosa’ with no irrigation (22.2%), while the least yield was from ‘Cristalina’ undergoing full irrigation (12.2%). In general, non-irrigated plants yielded more mucilage, their color was brighter and less green, and they had more protein and fiber. The viscosity and molar mass were greatest in non-irrigated plants. Total carbohydrate content was similar between non-irrigated and supplementally irrigated plants. Thus, for the cactus pear varieties studied here, either no irrigation or supplemental irrigation could be a feasible strategy to produce mucilage with good characteristics for agro-industrial and pharmaceutical use.

The bioactive compounds, antioxidant capacity and microbiological quality of melon juice processed by high-intensity ultrasound (HIUS) were studied. Melon juice was processed at two ultrasound intensities (27 and 52 W/cm²) for two different processing times (10 and 30 min) using two duty cycles (30 and 75%). Unprocessed juice was taken as a control. Total carotenoids and total phenolic compounds (TPC) were the bioactive compounds analyzed while the antioxidant capacity was determined by DPPH, ABTS and FRAP assays. The microbiological quality was tested by counting the aerobic and coliforms count as well as molds and yeasts. Total carotenoids increased by up to 42% while TPC decreased by 33% as a consequence of HIUS processing regarding control juice (carotenoids: 23 μg/g, TPC: 1.1 mg GAE/g), gallic acid and syringic acid being the only phenolic compounds identified. The antioxidant capacity of melon juice was enhanced by HIUS, achieving values of 45% and 20% of DPPH and ABTS inhibition, respectively, while >120 mg TE/100 g was determined by FRAP assay. Further, the microbial load of melon juice was significantly reduced by HIUS processing, coliforms and molds being the most sensitive. Thus, the HIUS could be an excellent alternative supportive the deep-processing of melon products.

The objective of this study was to evaluate the effect of an edible coating based on alginate and acemannan on the commercial quality and concentration of bioactive compounds of guava pieces stored in refrigeration. Pieces of guava were coated with an alginate film enriched with acemannan (A-Ac), with samples without cover used as a control. The fruit pieces with and without the A-Ac coating were stored for 12 days at 6 ± 2 °C. Analyses of colour, firmness, ethylene production, ascorbic acid, total polyphenols, antioxidant potential, and polyphenol profile were performed at 0, 3, 6, 9, and 12 days of storage. In addition, a sensory analysis was carried out after nine days of refrigeration. The coated guava pieces retained firmness at 2.8 N, while in the uncoated pieces, firmness decreased to 1.3 N. Similarly, the coated pieces showed better colour retention (ΔE<9) and lower ethylene emission during storage. Also, the content of ascorbic acid, total polyphenols, antioxidant capacity, and the concentration of individually identified polyphenols were higher in the pieces of guava coated with the A-Ac film. In addition, coated guava pieces, stored for nine days in refrigeration, showed greater sensory acceptability compared to uncoated samples. Therefore, applying the A-Ac cover could be a good alternative for conserving sensory attributes and bioactive compounds of guava pieces stored at low temperatures.