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The apple orchards with large land extensions represent a challenge in monitoring crops. Remote sensing techniques can analyze and obtain information on the general state of crops using multispectral data and vegetation indexes. This study aimed to analyze the flowering phenological of three apple orchards using images from Sentinel-2 satellite and a Phantom 4 pro/pro+ drone in three apple-producing regions. The images were processed using ArcGIS software and the Normalized Difference Vegetation Index (NDVI). The results were statistically analyzed through discriminant to classify and identify significant differences between the flowering phenological stages. NDVI maps were obtained for the study areas, and the NDVI values ranged from 0.09 to 0.26 and from 0.22 to 0.35 for drone and satellite images, respectively. It was possible to differentiate between two groups of phenological stages in the apple orchards (pre-bloom and post-bloom). The information generated can be a complementary tool for monitoring the apple tree crop.

Volatile compounds contribute to aroma and flavor, these being the main sensory attributes in food acceptance. This work addresses the physicochemical, volatile compounds, polyphenols, and flavonoids content and, antioxidant activity of apple-raspberry (90/10%) juice treated by thermal and ultraviolet radiation (UV-C) alone or in combination with moderate heat-treatment. Nineteen volatile compounds were identified which experienced changes depending on the treatment. Compounds such as α-ionone and β-ionone, that contribute to raspberries characteristic aroma, were present in a greater concentration in the UV-C treatment and lower in the thermal treatment. Likewise, 2-methyl butyl acetate, which give a fruity-sweet aroma typical of apples was present in a greater concentration in the UV-C treatment. Regarding polyphenol content, control and combined treatment presented the greater concentrations. However, after twenty days of storage, control and combined treatment presented the lower flavonoid concentration. Nevertheless, at this time, treatments showed no variations in antioxidant activity. Yeast and mold and total aerobic mesophilic and psychrophilic counts were reduced in the heat and combined treatments. In conclusion, UV-C and moderate heat might successfully be used to process a stable apple-raspberry juice while maintaining its quality and safety.

Diverse enzymatic reactions taking place after the killing of green vanilla beans are involved in the flavor and color development of the cured beans. The effects of high hydrostatic pressure (HHP) at 50–400 MPa/5 min and blanching as vanilla killing methods were evaluated on the total phenolic content (TPC), polyphenoloxidase (PPO), and peroxidase (POD) activity and the color change at different curing cycles of sweating–drying (C0–C20) of vanilla beans. The rate constants describing the above parameters during the curing cycles were also obtained. The TPC increased from C1 to C6 compared with the untreated green beans after which it started to decrease. The 400 MPa samples showed the highest rate of phenolic increase. Immediately after the killing (C0), the highest increase in PPO activity was observed at 50 MPa (46%), whereas for POD it was at 400 MPa (25%). Both enzymes showed the maximum activity at C1, after which the activity started to decrease. As expected, the L* color parameter decreased during the entire curing for all treatments. An inverse relationship between the rate of TPC decrease and enzymatic activity loss was found, but the relationship with L* was unclear. HHP appears to be an alternative vanilla killing method; nevertheless, more studies are needed to establish its clear advantages over blanching.

The objective of this study was to determine the antioxidant activity and bio compounds induced by salicylic acid (AS) and potassium (K) in ‘Flame’ grape peel and pulp. The applications were made in table grape of the ‘Flame’ variety, with 9 treatments and 3 repetitions, T1 control 0.0 (T2 AS 0.0, K 5 mM) (T3 AS 2.0, K 5.0 mM) (T4 AS 2.0, K 0 mM) (T5 AS 0.100, K 0.250 mM) (T6 AS 0.100, K 2. 50 mM) (T7 AS 1, K 2. 50 mM) (T8 AS 1, K .250 mM) (T9 AS 0. 25, K .625 mM) with 6 applications in the veraison stage throughout the cycle. The parameters of antioxidant capacity were determined by the DPPH and FRAP method, phenols, anthocyanins, flavonoids, pH, oBrix, titratable acidity and physical parameters in grape peel and pulp. Doses of AS 2.0, K 0 mM; AS 1, K 2.50 mM; and AS 0.25, K .625 mM influenced the increase in quality, as well as the bioactive and antioxidant activity. Anthocyanins were the main phenols in peel with 406.08 mg (C3G)/g-1. ‘Flame’ table grape peels have a high content of compounds, favouring the antioxidant activity. A serving of unpeeled table grapes could provide up to 110 mg of phenols. The use of salicylic acid and potassium can be an alternative to enrich the nutritional quality of the grape and benefit the health of the population.