Edible coatings based on 2% starch (w/v) extracted from tropical fruits were applied on stenospermocarpic mango fruits with the objective to prolong its shelf life during storage and give them an added value since they have no commercial value. In this regard, stenospermocarpic mangoes were coated with starch from banana “Pear” (T1 and T2), starch from soursop (T3 and T4), and starch from stenospermocarpic mango (T5 and T6), and two uncoated control treatments (T7 and T8). The fruit of T1, T3, T5, and T7 treatments were stored for 15 days (10 days at 10 ± 2°C and then at 22 ± 2°C for 5 days). The fruit of T2, T4, T6, and T8 treatments were stored for 10 days at 22 ± 2°C. Data were analyzed with a 4×2 factorial experimental design. Weight loss (g), firmness (N), total soluble solids content (%), titratable acidity (%), and color (L∗h∗C∗) were evaluated. The fruit coated with mango starch (T5) showed less weight loss (2.57%), greater firmness (18.6 N), as well as a high content of TSS (28.76%) compared with the control. The T5 extended the shelf life of the fruit up to 15 days (10 days at 10 ± 2°C and 5 days at 22 ± 2°C).

The maturity of two selections of soursop (G1 and G2) from Nayarit, Mexico, was evaluated under environmental conditions at 22°C and refrigeration at 15°C stored for 6 and 8 days, respectively. Maximum CO₂and ethylene values were present on the fifth and sixth day. The fruits exposed at 15°C had a significantly lower weight loss (5%) and showed no chilling injury. The firmness of two selections decreased more than 90%. The concentration of TSS increased to 5.3 to 15°Brix, and the titratable acidity was higher for fruit stored at 22°C. The highest concentration of phenols was recorded on the fourth day of storage at 22°C. The enzymatic activity of PPO was increased from physiological ripening to consumption ripening for both treatments. The two selections stored at 22°C registered the highest level of PME activity at ripeness. Shelf life was increased by up to 8 days (4 days at 15°C plus 4 days at 22°C) without causing chilling injury or alterations in the ripening process of the fruits. No significant differences were observed between the two selections evaluated; postharvest handling was considered to be similar; however, it would be advisable to evaluate other technologies combined with refrigeration.

Soursop leaves are a source of phytochemical compounds, such as phenolic acids, flavonoids, hydrolyzable tannins, and acetogenins. These compounds can have several types of biological activities. Lactic acid bacteria can uptake phenolic compounds present in plants or fruits. The aim of the present work was to investigate the in vitro effect of hexane, acetone, methanolic, and aqueous extracts of soursop leaves (Annona muricata L.) on the growth, motility, and biofilm formation of Lactobacillus casei, and to determine compounds related to growth. The minimum concentration promoting growth, motility (swimming, swarming, and twitching), and biofilm-forming capacity (crystal violet) were evaluated. The results showed the growth-promoting capacity of acetone and aqueous extracts at low doses 25–50 mg/L, and an inhibition in the four extracts at higher doses of 100 mg/L. The L. casei growth is related to ellagic acid, quercetin rhamnoside, kaempferol dihexoside, quercetin hexoside, secoisolariciresinol, and kaempferol hexoside-rhamnoside. Hexane extract increased the three types of motility, while aqueous maintained swimming and twitching motility similar to control. The four extracts inhibited the biofilm formation capacity.