Effect of Antibacterial Peptide Microsphere Coating on the Microbial and Physicochemical Characteristics of Tricholoma matsutake during Cold Storage

The effect of novel antimicrobial peptides (AMPs) and antimicrobial peptide microspheres (AMS) on the physicochemical and microbial quality of Tricholoma matsutake wild edible mushrooms was investigated. In the experiments, 1.0 g/L, 0.5 g/L of AMS, and 1.0 g/L AMPs were used as preservatives. Mushrooms coated with 1.0 g/L and 0.5 g/L of AMS as a preservative had better physicochemical and sensory qualities than did mushrooms coated with 1.0 g/L of AMPs. In the experiment, 1.0 g/L of blank microspheres without cathelicidin-BF-30 (PLGA-1.0) and distilled water was used as the control. Samples with these two treatments had minimal changes in texture, weight loss, total bacteria count, and sensory attributes. Research results suggests that the use of AMS can maintain the quality of Tricholoma matsutake wild edible mushrooms and could extend the postharvest life to 20 d.

Postharvest quality and shelf life of Passiflora cincinnata BRS Sertão Forte fruits according to type of fertilization and storage

The present study aimed to evaluate the physicochemical characteristics and shelf life of P. cincinnata BRS Sertão Forte fruits produced with conventional fertilization recommended for passion fruit, conventional organic fertilization, organic fertilization enriched with biotite schist, conventional fertilization with replacement of the potassium source and chemical fertilization only and the mineral nutrition of plants stored under ambient and refrigerated conditions. Analyses of pH, soluble solids, titratable acidity, ratio, color, texture and mass loss were performed. Fertilizers differed in terms of nutrient absorption associated with protein synthesis (N, S, B, Cu, Mn, Zn), especially where soil remineralizer was applied. Treatments without fertilization and that with organic fertilization enriched with biotite schist soil remineralizer also positively influenced fruit physicochemical properties such as color and texture. Fruits stored under refrigeration conditions showed the best results for the conservation of their qualitative characteristics. Under the conditions of the present study, it could be concluded that the postharvest life of P. cincinnata fruits stored under refrigeration at 100C is at least 60 days. This period is 30 days under ambient conditions.

Caracterización fisicoquímica y vida postcosecha de tres cultivares de jitomate (lycopersicum esculentum mil.) (SOLANACEAE) / Physicochemical characterization and postharvest life of three tomato cultivars (lycopersicum esculentum mill.) (SOLANACEAE)

El tomate es la hortaliza de fruto más cultivadas a nivel mundial. De esta existen múltiples genotipos, que están genéticamente creados para condiciones ambientales muy específicas, por ello es importante conocer el comportamiento postcosecha de los frutos, que resultará en el cultivar mejor recomendado para cada región. El objetivo general fue: realizar la caracterización fisicoquímica y postcosecha de tres genotipos de jitomate, cultivados bajo condiciones de invernadero, en Tehuacán Puebla, México. La investigación se llevó a cabo en laboratorio. Los genotipos fueron: Merlisse, Maxcesa y Komet tipo bola, cultivados bajo invernadero. Las variables respuesta fueron: diámetro ecuatorial y polar, dinámica del peso de fruto, color de fruto, firmeza, contenido de Ca++ y K+ y vida postcosecha. El diseño utilizado fue completamente aleatorizado, cuyos tratamientos fueron los cultivares y siete repeticiones (3 x 7)= 21 unidades experimentales. Los resultados indican, que el mayor diámetro ecuatorial y polar así como pérdida de peso, fueron en Maxcesa, mientras que Komett, presentó la mayor firmeza y contenido de Ca++ y K+, siendo este último quien presentó la mayor vida de anaquel. De esta investigación se puede concluir, que el cultivar Komett, es quien mejor se adapta a las condiciones del valle de Tehuacán, Puebla.

Quality Attributes of Chitosan-Coated Cornelian Cherry (Cornus mas L.) Fruits under Different Storage Temperatures

Temperature is the dominant environmental stimulus that influences the postharvest quality, visual appearance, and nutritional content of fruits. Temperature hastens fruit ripening and senescence by the impact on respiration rate and the acceleration of metabolic reactions. This study was conducted to select the optimized temperature for preserving the quality-related traits and antioxidant potential of cornelian cherry fruits after harvest. The fruits were treated with 1% chitosan and then kept under 0, 5, 10, and 21 °C for 21 days. The results revealed that fruits kept under lower than room temperature (21 °C) better retained antioxidant capacity and had higher levels of phenolics, flavonoids, and anthocyanins and even higher antioxidant enzyme activity, hence attaining prolonged postharvest life. Considering the quantity attributes and the shelf life, the temperature of choice was 0 °C. Zero temperature was also the best to keep the antioxidant capacity of cornelian cherry fruits. Overall, the results showed that low temperature and chitosan pretreatment provide an efficient method for maintaining the nutritional quality and antioxidant capacity of cornelian cherry fruits during storage time.

Antioxidant activity of thymol essential oil and inhibition of polyphenol oxidase enzyme: a case study on the enzymatic browning of harvested longan fruit

Background Enzymatic browning and microbial decay are the primary concerns that limit the postharvest life of longan fruit. These factors can be effectively prevented by sulfur dioxide (SO2) fumigation; however, due to the safety and regulatory issues of SO2, other alternatives must be tested. In this study, antioxidant and antimicrobial activities of thymol were determined against the pericarp browning and decay of longan fruit. A simple, cost-effective method was designed for its controlled release. Thymol vapors were obtained from the slurry prepared from 5 g of thymol in 5 mL of distilled water in a 180-mL glass jar, hermetically sealed and allowed for 24 h to accumulate the vapors in the headspace. Fruits were packed in polyethylene packages and fumigated with thymol through a septum. Non-fumigated fruits served as control and all the packages were stored at 25 ± 2 °C for 8 days. Results Thymol significantly (P ≤ 0.05) retarded pericarp browning (BI), delayed the decay incidence (DI) and maintained high color values of longan pericarp. Thymol also retained high total phenolic (TPC) and total flavonoid (TFC) contents, inhibited polyphenol oxidase (PPO) and peroxidase (POD) activities than those in control. A high coefficient of correlation of PPO with BI (r = 0.86), L* (r = − 0.94), weight loss (r = 0.93), TPC (r = − 0.77), TFC (r = − 0.80), DI (r = 0.92) and many other quality and color parameters indicated the antioxidant efficacy of thymol. Longer shelf life of 8 days with good quality attributes was obtained in thymol-treated fruits than 6 days in control. Conclusion Thymol could be effectively used as a natural antioxidant for a wide range of fruits. Graphic abstract

Maintaining antioxidants in tomato fruit using chitosan and vanillin coating during ambient storage

A high intake of antioxidants in a daily diet could reduce the risk of several diseases, including certain cancers and heart disease. Tomato is one of the rich sources of antioxidant compounds. However, it has a relatively short postharvest life due to several factors such as postharvest diseases, accelerated ripening and senescence that hasten the losses in quantity and quality. Chitosan and vanillin could be an alternative to disease control, maintain the quality and prolong the shelf life of fruit. This research aimed to evaluate the potential of chitosan and vanillin coating on tomato antioxidant properties during storage at 26±2°C and 60±5% relative humidity. Chitosan and vanillin in aqueous solutions of 0.5% chitosan + 10 mM vanillin, 1% chitosan + 10 mM vanillin, 1.5% chitosan + 10 mM vanillin, 0.5% chitosan + 15 mM vanillin 1% chitosan + 15 mM vanillin and 1.5% chitosan + 15 mM vanillin, respectively, were used as edible coating on tomato fruit. The analysis was evaluated at a 5-day interval. The results revealed that 1.5% chitosan + 15 mM vanillin have significantly retained tomato's antioxidant properties and prolonged shelf life up to 25 days without any adverse effects on fruit quality. Thus, combining 1.5% chitosan and 15 mM vanillin is highly recommended as a tomato coating to maintain their quality, particularly in the absence of a refrigeration facility during marketing.