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Abstract: Effects of ozonised water, gaseous ozone exposure, and their combined treatments on microbiological and qualitative parameters of two globe artichoke cultivars (Violet de Provence and Romanesco clone C3) were studied during storage at 4°C. At the end of this period, microbial counts were significantly lowered. Considering the qualitative parameters, ozone can be successfully applied to cv. Romanesco clone C3 without significantly increasing the respiration rate, while it could determine the acceleration of senescence in Violet de Provence heads. The storage under ozone-enriched atmosphere improved the initial polyphenol content in Violet de Provence, while for Romanesco clone C3 it seemed to be opportune to interrupt the ozonisation within the 4th day of storage for preventing excessive losses of polyphenol content. The ascorbic acid reduction, for both cultivars, was significantly increased by postharvest treatments with gaseous ozone suggesting to reduce, also in this case, the exposure days to the gas. Industrial relevance: The globe artichoke is a herbaceous crop native to the Mediterranean basin, which gives an important contribution both to agricultural economy and to human health due to the high content of promoting nutrients. Unfortunately, globe artichoke heads are very perishable because of their high respiratory activity, susceptibility to weight loss, and microbial decay. In particular, fungal decay is one of the main factors affecting the postharvest quality of globe artichoke and, so far, it is controlled by the application of chemical fungicides. However, resistance phenomena in microbial populations, growing public health and environmental concerns are urging for the use of alternative treatments. Among them, ozone is one of the most promising technologies from the health and environmental points of view for its spontaneous decomposition to non-toxic product. In addition, it has emerged as a potential antimicrobial agent in the post-harvest treatment of fruits and vegetables and is able to decompose pesticides and chemical residues. On the other side, the effect of ozone treatments on other qualitative parameters, including the level of antioxidant compounds, is highly dependent on the commodity and storage conditions. In this view, the combined water ozonisation/O3-atmosphere storage represents innovative and applicable postharvest treatments for globe artichoke, whose exposure time and concentrations need to be customized for each cultivar. [Copyright &y& Elsevier]

Wickerhamomyces anomalus killer strains are important for fighting pathogenic yeasts and for controlling harmful yeasts and bacteria in the food industry. Targeted disruption of key genes in β-glucan synthesis of a sensitive Saccharomyces cerevisiae strain conferred resistance to the toxins of W. anomalus strains BS91, BCA15 and BCU24 isolated from olive brine. Competitive inhibition of the killing activities by laminarin and pustulan refer to β-1,3- and β-1,6-glucans as the main primary toxin targets. The extracellular exoglucanase-encoding genes WaEXG1 and WaEXG2 from the three strains were sequenced and were found to display noticeable similarities to those from known potent W. anomalus killer strains. Accession Nos for WaEXG1 genes for the strains in brackets are JQ734563 (BS91), JQ734564 (BCA15) and JQ734565 (BCU24); for WaEXG2 genes JQ734566 (BS91), JQ734567 (BCA15) and JQ734568 (BCU24), respectively. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The present study investigated chemical and sensory properties of Malvasia delle Lipari DOC (Denomination of Controlled Origin) wine fermented with a crytolerant strain of Saccharomyces uvarum, characterized by low levels of acetic acid production. In particular, experimental wine was tested for volatile acidity and for aromatic profile by gas chromatography and the results were compared with the same wine produced with a commercial strain of Saccharomyces cerevisiae. Sensory analysis was carried out to assess the identification of experimental wine as Malvasia delle Lipari by defining its sensory profile. Fermentation with S. uvarum gave a final product with lower volatile acidity, lower alcohol content and higher total acidity. Moreover, differences in the aroma profile could be ascribed to different characteristics of the yeasts. Concerning sensorial analysis, the panel assigned higher scores in positive attributes to the wine fermented with S. uvarum [ABSTRACT FROM AUTHOR]

Abstract: The yeast population of minimally processed orange slices, packaged both in normal and modified atmosphere and with films of different permeabilities, was studied in order to set up the most suitable packaging conditions. Modified atmosphere resulted in a fermentative association of yeast strains, with the dominance of Saccharomyces cerevisiae strains. In samples packaged in normal atmosphere isolated strains have been mainly identified as Rhodotorula spp. [Copyright &y& Elsevier]

This study evaluated the effectiveness of a novel pectin-based edible coating (PBEC), alone or added with the antagonistic yeast Wickerhamomyces anomalus BS91 (PBECY), in reducing postharvest rots of Tarocco orange fruit. Their antifungal efficacy was assessed in vitro and in vivo , as well as their ability to preserve fruit quality under refrigerated conditions on three different cultivars, comparing a commercial wax amended with a fungicide. For all the treatments, the decay incidence, physiological disorders, weight loss and physical-chemical parameters were evaluated. The in vivo test results indicated that PBECY enhanced the antifungal effect compared to PBEC, given the significant reduction (p ≤ 0.01) of Penicillium digitatum (PD) decay incidence (up to 90%). After 30 d of cold storage, both PBEC and PBECY reduced fruit decay (p ≤ 0.05) in all cultivars, with values between 0 and 1.2%, relatively to the untreated control (up to 10%). Pectin-coated fruit showed a cultivar-dependent weight loss, with values comparable or higher to the other treatments, respectively for T. Lempso and T. Messina, whereas weight loss in T. Sciara was higher only when coated with PBEC. Fruit physical and chemical parameters were preserved until 30 d of storage, thus demonstrating the potential of this edible coating for future industrial application. • Pectin-based coating was tested alone (PBEC) or with a biocontrol yeast (PBECY). • Postharvest Penicillium rot during cold storage was determined on 'Tarocco' orange • Physiological disorders, weight loss and physico-chemical parameters were evaluated. • PBECY significantly reduced Penicillium digitatum growth with respect to PBEC. • Fruit physical and chemical parameters were preserved until 30 days of storage. [ABSTRACT FROM AUTHOR]

White colony-forming yeast (WCFY), also referred to as film forming yeast or spoilage yeast, that appear on the surface of kimchi can deteriorate the sensory properties of kimchi, such as odor and texture. Thus, the aim of this study was to develop a method to inhibit the formation of the white colony in kimchi. First, alterations in kimchi manufacturing and storage conditions, including temperatures, pH, salinity, and anaerobic condition, were investigated to determine if they could inhibit the growth of WCFY (i.e., Kazachstania servazzii, Candida sake, Debaryomyces hansenii, Pichia kudriavzevii, and Hanseniaspora uvarum). Thereafter, the anti yeast activity of freeze-dried garlic powder (FGP) and cinnamon ethanol extract (CEE) was evaluated against WCFY using the agar-well diffusion assay. Following the direct application of FGP and CEE to the surface of the kimchi, the inhibitory effects on white colony were determined. The results showed that WCFY can grow under various manufacturing and storage conditions of kimchi. Regarding the growth inhibitory effect on WCFY, FGP exhibited anti yeast activity against four WCFYs. It did not show anti yeast activity against K. servazzii. However, CEE showed anti yeast activity against K. servazzii. In particular, the mixture of 10% FGP and 1.75% CEE, which was manufactured considering the influence of sensory properties in kimchi, exhibited anti yeast activity against all WCFY. Furthermore, the application of the FGP and CEE mixture supplemented with 0.02% xanthan gum to kimchi to enhance adhesion to the kimchi surface, led to a delay in the formation of a white colony on the surface of the kimchi by an average of 17 d at 10 °C compared to the control group. Collectively, the use of a FGP, CEE, and xanthan gum mixture could be an effective method for the inhibition of white colony formation on the surface of kimchi, extending its shelf life. [ABSTRACT FROM AUTHOR]