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The cheese ripening period, in which biochemical changes occur under specific temperature and humidity conditions, is crucial for making the finished product marketable. However, the food matrix can become a growth medium for developing spoilage microorganisms and fungi. In dairy factory, contamination of the crust area can be monitored with several wasteful and time-expensive methods, i.e., the use of saline solutions and/or the brushing of cheese wheels. This study investigates the effectiveness of different ozone treatments, 400 ppb, 8 hours (overnight) every other day until the end of ripening, and 300 ppb, 8 hours per day (overnight) for the entire ripening duration compared to control sample in normal atmosphere, in controlling microbial and fungal growth during the ripening of Toma Piemontese PDO cheese. Results showed that ozone treatments significantly affect spoilage microflora, preserving the overall quality parameters (i.e., weight loss, customer value, and greater sensory nuances). [ABSTRACT FROM AUTHOR]

The kiwifruit, for which Italy is the second largest producer in the world, is derived from a fruit vine that requires a significant amount of water for proper growth and the production of high-quality fruit. This study aims to investigate the ideal irrigation strategy to ensure an adequate water supply for robust root development, vibrant foliage, and successful fruit production. To achieve this goal, three experimental plots of Soreli kiwifruit vineyards were subjected to different water regimes: full irrigation (100%) and two plots with 80% and 60% irrigation. Each irrigation group was equipped with an Internet of Things (IoT) TT Spectrum, which measured reflected spectrometer data in 12 bands. Additionally, a soil sensor was used to determine moisture content. Fruit quality analysis, including weight loss, soluble solid content, flesh color and firmness, titratable acidity, ascorbic acid, polyphenols and flavonoids, was conducted to correlate productivity with water availability. By analyzing the IoTTT Spectrum data for each kiwifruit plant, crucial indicators for assessing physiological status, health, and growth were examined. Maintaining a balance between leaf nitrogen content and photosynthetic capacity, with low AI and higher NDVI and CVI values, was used to determine the optimal irrigation level for each of the three plots. Furthermore, qualitative data obtained from fruits revealed that overwatering or underwatering kiwifruit plants affects yield production and fruit quality. Fruits subjected to full irrigation exhibited lower sugar levels compared to those under deficit irrigation. This study demonstrates that excessive or limited irrigation regimes negatively impact plant health and on the fruit quality. [ABSTRACT FROM AUTHOR]

BACKGROUND: Among the challenges for postharvest researchers is that of understanding the physiological and biochemical pathways associated with postharvest fruit decay. Fruit senescence directly affects sensorial and nutritional quality during postharvest life. It has been clarified that reactive oxygen species and oxidative damage are responsible for fruit senescence. Some cultivars of yellow‐fleshed kiwifruit can be stored for a short period compared with green‐fleshed kiwifruit. Postharvest performance is affected by the physiological state of the fruit at harvest, associated with its postharvest management. Among several postharvest applications, ozone treatment is considered as a cost‐effective and eco‐friendly food‐processing technology to preserve the fruits' quality during cold storage. In this study, we investigated the influence of ozone, after gradual cooling treatment, on the antioxidant defense system in Actinidia chinensis, 'Soreli'. RESULTS: Bioactive compound content decreased during cold storage, and ozone treatment enhanced the activities of superoxide dismutase and catalase during cold storage. This treatment preserved membrane integrity by inhibiting lipoxygenase activity and malondialdehyde accumulation. A multivariate statistical approach, using principal component analysis, provided the global response to the effect of ozone postharvest treatment during cold storage in kiwifruit 'Soreli'. CONCLUSION: Ozone treatment improves the efficiency of antioxidative system and storability of 'Soreli' kiwifruits. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The storage of chestnuts is a highly critical phase due to the considerable postharvest losses of the product with relevant commercial impact. The effect on the chemical quality parameters of chestnuts treated with 300 ppb of gaseous ozone in air or in atmospheric air at T = 2 °C for 150 days during the storage has been investigated. The ozone treatment increased sucrose and total sugar contents; while tocopherols were reduced. No significant differences in weight loss and fatty acid content were recorded between chestnut treated with ozone and untreated fruits (P ≥ 0.05). In addition, chestnut ozone exposure for 150 days reduced the total microbial populations associated with the pericarps of about 1.6 logs for mesophilic bacteria and 1.0 logs for fungi. Overall, our results suggested that gaseous ozone treatment is a valid and economic technology to ensure the shelf life quality of chestnut during the long storage periods. [ABSTRACT FROM AUTHOR]

BACKGROUND A trial was conducted to evaluate the effect of postharvest gaseous ozone (O3) treatment on quality parameters and cell wall enzymes of cantaloupe melon cv. Caldeo during storage at 6 °C for 13 days. Fruits were kept in cold storage and treated with 0.15 ppm gaseous O3 during the day and 0.3 ppm overnight; control fruits (CK) were stored in normal atmosphere. RESULTS Firmness was higher and ethylene concentration significantly lower in O3 fruits compared with CK fruits. During storage, microbial counts were lower in both O3 and CK fruits; from day 9, O3 fruits showed a significant decrease in mesophilic aerobes. Additionally, total carotenoids had a tendency to be higher, with no significant differences between CK and O3 fruits. The same trend was observed for ascorbic acid, colour, total soluble solids content and acidity. Finally, O3 treatment reduced the activities of cell wall enzymes α-arabinopyranosidase, β-galactopyranosidase and polygalacturonase starting from day 3 of storage. Pectin methyl esterase activity did not seem to be affected by O3 treatment. CONCLUSION Gaseous O3 treatment during cold storage was effective in decreasing ethylene production and delaying fruit softening in cantaloupe melon by extending quality maintenance. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In recent years, different postharvest alterations have been detected in garlic. In many cases, the symptoms are not well defined, or the etiology is unknown, which further complicates the selection of bulbs during postharvest handling. To characterize the different symptoms of bulb rot caused by fungi, garlic bulb samples were collected from six Spanish provinces in two consecutive years. Eight different fungal species were identified. The most prevalent postharvest disease was Fusarium dry rot (56.1%), which was associated with six Fusarium species. Fusarium proliferatum was detected in more than 85% of symptomatic cloves, followed by F. oxysporum and F. solani. Pathogenicity tests did not show a significant correlation between virulence and mycotoxin production (fumonisins, beauvericin, and moniliformin) or the mycelial growth rate. Penicillium allii was detected in 12.2% of the samples; it was greatly influenced by the harvest season and garlic cultivar, and three different morphotypes were identified. Stemphylium vesicarium and Embellisia allii were pathogenic to wounded cloves. Some of the isolated fungal species produce highly toxic mycotoxins, which may have a negative impact on human health. This work is the first to determine the quantitative importance, pathogenicity, and virulence of the causative agents of postharvest garlic rot in Spain. [ABSTRACT FROM AUTHOR]

Worldwide undernutrition affects over 820 million individuals and is the underlying cause of over 50% of all childhood deaths. Sweet potatoes have been promoted to address vitamin A (vitA) deficiency, with a single, orange-fleshed sweet potato (OFSP) providing enough vitA, as β-carotene, to meet daily needs. However, the bioavailability of β-carotene is dependent on the presence of dietary fat, which is not provided by OFSP, and it lacks some essential amino acids. Therefore, in an attempt to create a food product that meets daily vitA requirements with adequate bioavailability and complete protein, we designed and assessed a sweet potato, peanut paste, and legume product. The final food product formulation, developed through computer modeling, resulted in a 65/5/35 (w/w/w) formulation in a 250 g serving and ~330 kcal. We then confirmed the nutrient content of macronutrients, and essential amino acids, zinc, and iron contents. Total β-carotene was assessed by HPLC and was lower than predicted through computer modeling, likely due to losses through thermal processing and/or degradation from storage. The results of this project indicate that the three ingredients can be combined into a single 250 g food product to provide >300 kcal energy, complete protein, and micronutrients in a more bioavailable form. [ABSTRACT FROM AUTHOR]

Increasing demands by consumers for fresh, nutritional, and convenient food has led to the increase of fresh-cut produce market. Nowadays, there is a turn towards the investigation of natural products (i.e., essential oils, organic acids, and edible coatings) in an effort to lower the usage of chemical synthetic compounds (i.e., chlorine) as postharvest sanitizers. The aim of the present study was to assess the effectiveness of Origanum majorana essential oil (EO), ascorbic acid (AA), chitosan, and their combinations on quality attributes of fresh-cut lettuce stored for six days at 7 °C. When applied, Chitosan+AA resulted to a less acceptable product (visual quality and aroma), while the application of marjoram EO was able to preserve the visual quality of fresh-cut lettuce and at the same time resulted in a pleasant aroma. The application of EO+AA and Chitosan+AA increased total phenolics and antioxidant levels of fresh-cut lettuce on the fourth and sixth day of storage. The EO and EO+AA increased damage index (hydrogen peroxide and lipid peroxidation) of fresh-cut lettuce, while at the same time these treatments decreased the activity of enzymes related with plant tissue browning (i.e., peroxidase activity and polyphenol oxidase). Chitosan decreased total valuable counts and yeasts and molds counts on the sixth day of storage, while EO, AA, EO+Chitosan, and Chitosan+AA decreased yeasts and molds after four days of application. The findings of the present work indicating that the combination of marjoram EO, AA, and chitosan could be considered further as alternative means for fresh-cut produce preservation. [ABSTRACT FROM AUTHOR]

Among the many consumers in Slovakia, smoothies are nowadays gaining popularity. Smoothie drinks are prepared from raw fruits and vegetables. Therefore, their microbiological safety depends on hygiene standards. The aim of this work was to monitor and quantify selected sensitive and antibiotic-resistant microorganisms present in collected smoothies. Twenty analyzed smoothie samples were collected from six food service establishments (fresh bars) in the capital city of Slovakia, Bratislava. Antibiotic-resistant bacteria were found in at least one of each fresh bar. Antibiotic-resistant coliform bacteria prevailed, especially in green smoothies or juices containing more vegetable ingredients. Resistance to ampicillin, ciprofloxacin, tetracycline, chloramphenicol, and gentamicin was observed in the case of coliform bacteria. More than half of the smoothie drink samples did not contain resistant enterococci. On the other hand, vancomycin-resistant enterococci were detected in 20% of samples. The most frequently isolated antibiotic-resistant strains belonged to the Enterobacter spp. or Klebsiella spp. genus. In the last part of the work, the pretreatment effect of smoothie components on the selected microorganisms' counts in the final product was investigated. Washing ingredients with an aqueous solution of a biocide agent containing silver and hydrogen peroxide proved to be the most effective way to decrease bacterial counts. [ABSTRACT FROM AUTHOR]

Summary: Salicylic acid (SA), ethylene (ET), and wounding are all known to influence plant defense response. Experiments attempting to determine SA''s relation to ET biosynthesis and defense gene expression have shown conflicting results. To confront this, we developed an in vitro model system to investigate how SA affects ET biosynthesis, hydrogen peroxide (H2O2) production and endochitinase gene expression in the European chestnut. ET measurements of in vitro shoots indicated a critical time point for SA exogenous application, enabling us to study its effects independent of ET. In addition, ET measurements demonstrated that its own increased biosynthesis was a response to wounding but not to SA treatment. Application of the ET biosynthesis inhibitor, aminoethoxyvinylglycine (AVG), on wounded and SA-treated shoots blocked wounding-induced ET production. Interestingly, SA inhibited ET production, but to a lesser extent than AVG. Additionally, SA also induced the accumulation of endochitinase transcript level. Likewise, a sensitive tissue-print assay showed that SA further increased the level of H2O2. Yet, SA-induced endochitinase gene expression and SA-enhanced H2O2 production levels were independent of ET. The cumulative results indicate that SA acts as an inducer of endochitinase PR gene expression and of H2O2 oxidative burst. This suggests that SA is a component of the signal transduction pathway leading to defense against pathogens in chestnut. Further, the model system developed for this experiment should facilitate the deciphering of defense signaling pathways and their cross-talk. Moreover, it should also benefit the study of trees of long generation time that are known to be recalcitrant to in vitro studies. [Copyright &y& Elsevier]