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Funding Information This study was supported by Project BIOSAFE funded by FEDER through the Programa Operacional Factores de Competitividade–COMPETE and by Fundação para a Ciência e a Tecnologia (FCT, Portugal)—Grant LISBOA-01-0145-FEDER-030713, PTDC/CAL-EST/30713/2017 and by FCT through funds to GHTM (UID/04413/2020), CIISA Project (UID/CVT/00276/2020), and Project PTDC/CVT-CVT/28469/2017. The contributions of Andrea T. Feßler and Stefan Schwarz were financially supported by the German Federal Ministry of Education and Research (BMBF) under project numbers 01KI1727D and 01KI2009D as part of the Research Network Zoonotic Infectious Diseases. Part of this research was supported by Cost Action CA18217: European Network for Optimization of Veterinary Antimicrobial Treatment (ENOVAT). Apramycin and florfenicol are two antimicrobial agents exclusively used in veterinary medicine. Resistance determinants to these antimicrobial agents have been described in several staphylococci, yet no inhibition zone-based epidemiological cutoff (ECOFF) values are available to detect populations harboring resistance mechanisms. In this study, we propose disk diffusion inhibition zone ECOFF values of Staphylococcus aureus for apramycin and florfenicol. The susceptibility to apramycin and florfenicol was evaluated by disk diffusion of five S. aureus collections, comprising 352 isolates of animal (n = 265) and human (n = 87) origin. The aggregated distributions of inhibition zone diameters were analyzed by the normalized resistance interpretation method to obtain normalized wild-type (WT) population distributions and corresponding ECOFF values. The putative WT populations of S. aureus were characterized by an inhibition zone ≥15 mm (ECOFF = 15 mm) for apramycin and ≥21 mm for florfenicol (ECOFF = 21 mm). Five nonwild-type (NWT) isolates were detected for apramycin, all without inhibition zone and harboring the apmA gene, whereas five NWT isolates were identified for florfenicol, all carrying the fexA gene. The proposed ECOFF values for apramycin and florfenicol may be a valuable tool in future antimicrobial resistance monitoring and surveillance studies to identify S. aureus NWT populations toward these antimicrobial agents. publishersversion published

Currently, cereal bars are gaining interest globally because of their nutritionally balanced and convenient nature. One healthy strategy is to add probiotics to cereal bars, to make them a functional food product. So, in this study a cereal bar functionalized with edible coatings of whey protein isolate (WPI) and alginate (ALG) incorporated with Bifidobacterium animalis subsp. lactis BB-12 and inulin was developed and evaluated for its consumer acceptability and physicochemical and microbiological properties, throughout 90 days of storage. WPI-coated cereal bars were shown to be the solution that better maintained the level of the incorporated probiotic strain when compared to the ones coated with ALG, throughout storage and throughout in vitro gastrointestinal digestion. The physicochemical properties of the bars, namely aw, moisture content, color and texture, were not altered during the storage period. The sensory evaluation showed that coated bars were accepted as well as control bars. Moreover, the consumers appreciated better the odor and flavor of WPI-coated bars than those of ALG-coated bars.

Horticultural crops are vulnerable to several disorders, which affect their physiological and organoleptic quality. For about forty years, the control of physiological disorders (such as superficial scald) in horticultural crops, particularly in fruit, was achieved through the application of the antioxidant diphenylamine (DPA), usually combined with controlled atmosphere (CA) conditions. However, identification of DPA residues and metabolites in treated fruits, associated with their toxicity, banned the use of this antioxidant in Europe. This triggered the urgent need for novel and, ideally, natural and sustainable alternatives, combined with adequate storage conditions to protect cultivars from harmful agents. This review systematizes the state-of-the-art DPA application on several fresh cultivars, such as apples, pears, and vegetables (potatoes, spinach, etc.), as well as the possible mechanisms of the action and effects of DPA, emphasizing its antioxidant properties. Alternative methods to DPA are also discussed, as well as respective effects and limitations. Recent research on scald development molecular pathways are highlighted to open new non-chemical strategies opportunities. This appraisal shows that most of the current solutions have not lead to satisfactory commercial results; thus, further research aimed to understand the mechanisms underlying postharvest disorders and to design sustainable and safe solutions to improve horticultural products storage is needed.

Fresh-cut cantaloupe melon is valued for its aroma but is highly perishable. Temperature of storage (typically 0-5°C) is critical for maintaining fresh-cut melon quality, but often reaches 10 °C during transportation and in retail outlets. A comparison amongst 0, 5 and 10 °C storage temperatures for fresh-cut melon over 14 days reveals that storage at 0 °C is optimal for avoiding increases in microbial load and loss of vitamin C especially at later time points. However, higher temperatures maintain better the balance of esters (acetate versus non-acetate) and phenolic content. The whole volatile organic compound (VOC) profile can be used to discriminate both time and temperature effects especially at earlier time points. Potential VOC markers for changes in vitamin C from day 0 to day 6 of storage (3-methyl butane nitrile) and temperature (limonene) are identified through a multi-trait analysis.

Effective and efficient design of modified atmosphere packaging (MAP) systems for ready-to-eat (RTE) products requires knowledge on produce respiration rate under various temperatures and oxygen levels. In order to model the respiratory behavior of RTE rocket leaves under different storage conditions, leaves respiration rate was measured during storage under four initial oxygen partial pressures (2.5; 5; 10 and 20 kPa O2) and three temperatures (0, 5 and 10 °C), for 10 days. The respiratory quotient was determined and found to range between 0.6 and 1.3. Temperature showed a significant impact on respiration rate and the effect of oxygen partial pressures was found to be temperature-dependent. The oxygen pressure effect on respiration rate was accurately described using Michaelis–Menten kinetics, without inhibition by carbon dioxide, and the effect of temperature was well modeled by exponential functions. Monte Carlo simulation allowed quantification of the relative impact of the reduction of oxygen pressure and temperature on the decrease in respiration rate and the potential shelf life increase of RTE rocket leaves. Temperature contributed to more than 80% of the Michaelis–Menten model variance while oxygen pressure contributed only with 13%. The model obtained is a useful tool for defining packaging and storage conditions for a shelf-life extension of rocket leaves.

Lysophosphatidylethanolamine (LPE) is a naturally occurring lipid with regulatory effects in senescence and ripening. When applied exogenously to horticultural crops, LPE affects growth, development, and postharvest longevity. The effects of exogenously applied LPE have been studied in a range of plant organs in more than a dozen horticultural species. The claimed horticultural benefits include delayed leaf senescence, stimulation of ripening in table grape, acceleration of color development and extension of shelf-life in cranberry and tomato, and increased vase life of cut flowers. Responses to LPE application are found to vary dramatically within horticultural commodity, developmental stage, and organ type. Effects on ethylene responses are contradictory. LPE inhibits phospholipase D and is reported to affect the activity of enzymes relevant for produce quality, such as phenylalanine ammonia lyase and acid invertase. The biochemical mode of action of LPE is poorly understood. In particular, a mechanism by which a plant growth regulator might delay senescence of plant organs and accelerate ripening-related changes is not obvious. The horticultural, physiological and biochemical effects of LPE are reviewed in an attempt to highlight the knowledge gaps regarding the putative regulatory role of exogenously applied LPE.

BACKGROUND: Orange-fleshed cantaloupe melons have intense aroma and flavor but are very perishable during storage life. Fresh-cut processing enhances ethylene-mediated quality losses. Post-cutting 1-methylcyclopene (1-MCP) application to fresh-cut cantaloupe was evaluated for its effects on quality attributes, phytochemical content and aroma volatiles. RESULTS: Fresh-cut cantaloupe (Cucumis melo var. cantalupensis ‘Fiesta’) cubes treated with 1.0 µL L−1 of 1-MCP for 24 h at 5 °C, packaged in vented plastic clamshells and stored under normal atmosphere at 5 °C for 9 days, preserved their soluble solids, total phenolics, total carotenoids and β-carotene contents, but significant softening occurred. A significant increase of non-acetate esters and a decrease of aldehydes occurred during storage. Most quality attributes of fresh-cut cantaloupe were unaffected by the treatment with 1-MCP. 1-MCP-treated fresh-cut cantaloupe accumulated higher levels of propyl acetate, 2-methylbutyl acetate, methyl butanoate, methyl 2-methyl butanoate, methyl hexanoate, 2-methylbutyl alcohol and phenethyl alcohol, and lower levels of benzyl alcohol and heptanal than untreated controls. CONCLUSION: Post-cutting treatment with 1-MCP affected nine of the flavor-important volatiles, particularly those derived from the amino acids isoleucine and phenylalanine, but had no practical effect on phytochemicals or other quality attributes. © 2012 Society of Chemical Industry

To improve fertilisation recommendations in organic farming systems and nitrate vulnerable zones, the response of white cabbage to the application of increasing rates of mineral N (0, 90 and 180 kg ha-1) fertiliser in combination with increasing rates (0, 20 and 40 t ha-1) of an organic fertiliser from the composting process (182 days) of the solid fraction (SF) of dairy cattle slurry, was assessed in the summer season in NW Portugal. Cabbage yield was strongly related to mineral N application with an N recovery rate over 70%, but was not associated to SF compost application, except for treatments without mineral N fertilisation where cabbage dry weight increased (P

Cantaloupe and honeydew melon cultivars were processed and stored under a high oxygen passive modified atmosphere packaging (MAP) or reduced oxygen controlled atmosphere (CA; 5 kPa O2 + 10 kPa CO2 and balance N2) for 14 days at 5 °C. Atmosphere did not affect softening rate or soluble solids content and had a negligible effect on colour. Volatile compounds known as flavour-important in melons were extracted using stir bar sorptive extraction (SBSE) and quantified via GC-MS. Acetate esters increased more in MAP than in CA. Non-acetate esters increased markedly in both cultivars and storage types. Alcohols were more abundant in honeydew than in cantaloupe. Aldehydes decreased during storage in both cultivars and storage types. Lower O2 availability under CA conditions likely suppressed some of the esters relevant to the aroma of fresh-cut melon. Results suggest that package O2 levels are more important in determining aroma than other quality attributes of fresh-cut melon, and high O2 levels may be required to reveal desirable aroma compounds.

'Rocha' pear (Pyrus communis L.) was used as a model system to assess the effect of pH of dipping solutions on quality retention of fresh-cut fruit and its interaction with calcium additives. Pear slices were dipped for 60. s in a buffer solution at pH 3.0, 5.0 or 7.0 and stored at 4.5°C for 13 days. In other experiments, pear slices were dipped for 60. s in buffer solutions containing 250. mM of calcium ascorbate, lactate, chloride, and propionate, at pH 3.0 or 7.0, and stored at 4.5°C for 6 days. Browning and softening were more intense in slices dipped in a solution at pH 3.0 than at pH 5.0 or 7.0, but microbial growth was lower in slices treated at pH 3.0. The effect of calcium additives depended on the anion and significant interactions between the effects of calcium salt and pH were observed. Calcium ascorbate was very effective in preserving color and reducing microbial growth irrespective of pH, but enhanced pectin solubilization and tissue softening at pH 3.0. Slices treated with 250. mM calcium propionate or calcium lactate were softer and had higher electrolyte efflux when treated at pH 3.0 than at pH 7.0. Calcium lactate enhanced browning and reduced microbial growth at pH 3.0 but did not affect color or microbial counts at pH 7.0. All calcium treatments enhanced electrolyte leakage. pH of the dipping solution can affect, per se, the quality of fresh-cut fruit. The choice of calcium additives to prevent undesirable changes on visual and sensory quality of cut produce should involve pH ranges that provide the expected benefits.

Wounding increases the hydrolysis of phospholipids mediated by phospholipase D (PLD) in plant tissues. Subsequent reactions may originate flavor-related aldehydes and alcohols. Lysophosphatidylethanolamine (LPE) is a naturally occurring phospholipid capable of inhibiting phospholipase D in vitro. The effect of LPE on the quality and volatile profile of fresh-cut melon was investigated. Cantaloupe melons (Cucumis melo L. 'Fiesta') were processed into cubes, vacuum-infiltrated with 200 μg L-1 of LPE, packaged in plastic clamshells and stored at 5°C for 9 days. The activities of phospholipase D (PLD) and C (PLC), respiration and ethylene production rates, color, firmness, soluble solids content (SSC), and volatile production were measured during storage at 5°C for 9 days. LPE significantly reduced the activity of PLD and PLC one day after the treatment but the effect was transient. LPE did not affect ethylene production and had a negligible effect on the respiration rate of melon cubes. Firmness and SSC were not affected by the treatment but LPE induced a very small increase in hue angle. LPE did not affect the major classes of volatiles in melon -esters and alcohols -but reduced the accumulation of aldehydes typical of wounding after the first day of storage. In conclusion, LPE did not help in the quality retention of fresh-cut melon but had a specific inhibitory effect on aldehyde production.