Amalia Piscopo

Antimicrobial Effect of Some Essential Oils

Abstract Commercially available oils of lavender (Lavandula angustifolia Mill.), lemon-balm (Melissa officinalis L.), juniper berry (Juniperus communis L.), lemon verbena (Lippia citriodora Kunth), rosemary (Rosmarinus officinalis L.) and cypress (Cupressus sempervirens L.) were evaluated for their antimicrobial activity. Analyses of the oils by GC-FID and GC/MS revealed that the major constituents of these oils were linalool (23.1%) and linalyl acetate (23.1%) in lavender, citronellal (23.8%) and geranial (11.6%) in lemon-balm, α-pinene (29.2%) in juniper berry, neral (36.2%) and geranial (41.9%) in lemon verbena, 1,8-cineole (24.4%) and camphor (17.1%) in rosemary, α-pinene (31.1%) and δ-3-carene (18.6%) in cypress oil. The antimicrobial activity of the essential oils was evaluated on survival and growth of some microorganisms potentially dangerous to the safety of foods (Escherichia coli, Staphylococcus aureus, Listeria innocua). The antimicrobial tests were carried out both in solid and in liquid media. E. coli was the most sensitive organism among the tested ones to the inhibition effect of the oils.

Apricot melanoidins prevent oxidative endothelial cell death by counteracting mitochondrial oxidation and membrane depolarization

The cardiovascular benefits associated with diets rich in fruit and vegetables are thought to be due to phytochemicals contained in fresh plant material. However, whether processed plant foods provide the same benefits as unprocessed ones is an open question. Melanoidins from heat-processed apricots were isolated and their presence confirmed by colorimetric analysis and browning index. Oxidative injury of endothelial cells (ECs) is the key step for the onset and progression of cardiovascular diseases (CVD), therefore the potential protective effect of apricot melanoidins on hydrogen peroxide-induced oxidative mitochondrial damage and cell death was explored in human ECs. The redox state of cytoplasmic and mitochondrial compartments was detected by using the redox-sensitive, fluorescent protein (roGFP), while the mitochondrial membrane potential (MMP) was assessed with the fluorescent dye, JC-1. ECs exposure to hydrogen peroxide, dose-dependently induced mitochondrial and cytoplasmic oxidation. Additionally detected hydrogen peroxide-induced phenomena were MMP dissipation and ECs death. Pretreatment of ECs with apricot melanoidins, significantly counteracted and ultimately abolished hydrogen peroxide-induced intracellular oxidation, mitochondrial depolarization and cell death. In this regard, our current results clearly indicate that melanoidins derived from heat-processed apricots, protect human ECs against oxidative stress.

Effect of Some Essential Oils as Natural Food Preservatives on Commercial Grated Carrots

Abstract In the present work, the effects of lemon verbena (Lippia citriodora), cypress (Cupressus sempervirens) and lemon-balm (Melissa offcinalis) essential oils against the growth of three microorganisms (potentially dangerous to the safety of foods) were evaluated. The three oils were chosen and tested on grated carrots inoculated with bacteria and stored at 8°C until 8 days to simulate the market sale. The most resistant of the three strains against all the tested oils was Escherichia coli, while Listeria strain was the most easily influenced. An important interaction was revealed with the packaging type: oxygen diffusion greatly influenced the bacteria survival at the end of the experiment.

Characterization of monovarietal olive oils obtained from mills of Calabria region (Southern Italy)

The qualitative characteristics of four monovarietal olive oils produced in Calabria region (Southern Italy) were evaluated. The aim of this work was to evidence the differences on chemical parameters due to variety and to growing environment. Results demonstrated a large variability in qualitative indexes according to the variety. Most of the Grossa di Gerace oils sampled in Ionian Southern coast revealed a high total acidity (percentage upper 0.8% of oleic acid). Fatty acid composition showed some varietal characters: in Grossa di Gerace oils possessed a low content of oleic acid and many Carolea oils showed a heptadecenoic acid level higher than 0.3% as European Rules requires for the extra virgin olive oil category. Carolea cultivar is widely grown in different sites of Calabria and so it is influenced by the different climatic conditions: the obtained oils strongly differed according to the production area.

Packaging and Storage of Olive Oil

Storage is a very important step of any food, including olive oil. In fact, olive oil shelf life can be influenced by different factors, from olive quality to processing technologies, however, the selection of proper storage conditions, including packaging, can be of great importance. The Mediterranean diet is recommended as food model for the prevention of various chronic-degenerative pathologies (cardiac diseases, cancer etc.) and olive oil is surely the cornerstone of this type of nutrition with fruits, vegetables, legumes and fish. Its peculiar nutritional characteristics depend on the presence of antioxidant components and monounsaturated fatty acids that are predominant on unsaturated ones, with positive results in the increase of HDL (High-Density Lipoproteins) and reduction of LDL (LowDensity Lipoproteins) oxidation.

Shelf-life of Almond Pastry Cookies with Different Types of Packaging and Levels of Temperature

Almond pastries are typical cookies of the south of Italy. Introduction of new packaging for this kind of cookies requires shelf-life assessments. This study, related to different types of packaging under various storage conditions of time and temperature, identifies critical parameters, as color and texture, to track during storage studies and to extend the shelf-life. The cookies were packed in three different ways and stored at two different temperatures. The pastries were separately stored: (1) in polyvinylchloride film; (2) in aluminum foil (ALL); (3) with modified atmosphere (MAP) in plastic vessels sealed into a polyamide/ polyethylene film; and (4) in vessels without any polymeric film. The storage temperatures were 20 and 30 °C. Evolution of texture, water activity, dry matter and color was assessed. Texture was evaluated by a texture analyzer with a puncturing test. Indices for hardening were the area under the curve (N × mm) up to 10 mm of distance, and the maximum force (N) corresponding to the crust fracture. The best results were obtained with ALL packaging and MAP condition, and above all, in all the trials a temperature of 30 °C reduced the crust hardness.

Selected yeasts to enhance phenolic content and quality in red wine from low pigmented grapes

The aim of this work was to enhance—by yeast activity—the quality of red wine produced from black grapes of the Calabrian Gaglioppo variety, used as a model for grapes with reduced synthesis of anthocyanins. Six selected strains of Saccharomyces cerevisiae were used to control winemaking trials. Among the wines, there are significant differences, due to the wine starter used. The following technological parameters were significantly different from strain to strain: total acidity, alcoholic degree, tartaric, malic, lactic, and acetic acid, and free and total SO2; moreover, the following phenolic parameters were significantly different from strain to strain: A420, A520, A620, colour intensity, colour hue, Folin–Ciocalteu index, percentage of DPPH inactivation, total anthocyanins, total polyphenols (A280), total tannins, delphinidin-3-glucoside, cyanidin-3-glucoside, petunidin-3-glucoside, peonidin-3-glucoside, and malvidin-3-glucoside. From a sensory standpoint, significant differences were observed among wine samples during a short bottle aging. Data validate the main role that wine yeast selection plays in enhancing the quality of red wine from low pigmented grape.

Study of the inheritability of the yeast trait “interaction with natural antioxidant activity of red wine” in four generations of Saccharomyces cerevisiae and its enhancing by spore clone selection and hybridization

The aim of this research was to study the inheritability of the yeast trait “interaction with natural antioxidant activity of red wine” and to enhance this trait by spore clone selection and hybridization of wine yeasts. This research was carried out using as a model three strains of Saccharomyces cerevisiae (wild types), 24 derived spore clones, three hybrids obtained crossing the derived spore clones and 34 spore clones derived from the three hybrids. Using these yeast strains, micro-winemaking trials were carried out utilizing grape must of the black varieties, Cabernet and Magliocco: the wines showed significant differences, due to the wine starter used, both for Folin–Ciocalteu’s index and for DPPH analysis. Data validate the main role that wine yeast selection plays to enhance red wine content in antioxidant compounds. Data also demonstrate that using spore clone selection and hybridization, it is possible to significantly enhance the natural antioxidant activity of wines, so improving their quality and stability.

Data on some qualitative parameters of Carolea olive oils obtained in different areas of Calabria (Southern Italy)

This data article contains complementary results related to the paper “Characterization of monovarietal olive oils obtained from mills of Calabria region (Southern Italy)” (Piscopo et al., 2016) [1]. Data was obtained by capillary-column gas chromatography, analyzing sterols and triterpene dialcohols and ethyl esters in the composition of Carolea olive oils. They were produced in different areas of Calabria region (Southern Italy), named: the Sibari׳s plateau (SP), the Valley of Sant׳ Eufemia (VSE), the Tyrrhenian southern area (TSA), the Ionian southern coast (ISC) and the Ionian area of Catanzaro (IAC). Specifically the characterized samples were 24 in the SP; 43 in the VSE; 15 in the TSA; 30 in the ISC, and 34 in the IAC, for a total amount of 146 olive oils. The differences in some compositional characteristics denoted the effect of the environmental and could be considered to improve the local productions. The compilation of this data provides a resource for the wider research community and the interpretation of this data could be found in the research article noted above.

Influence of Light Exposure during Cold Storage of Minimally Processed Vegetables (Valeriana sp.)

Minimally processed vegetables are sensitive to leaves discoloration and quality deterioration, and these negative aspects can affect their shelf life. During the manufacturing processing, Valeriana leaves were submitted to different dipping acid solutions and then were stored at cold temperature in dark and in light to study the influence of the light exposure on their quality in terms of total free acidity, dry matter percentage, colour, water activity, total bacterial count, antioxidant components, and total antioxidant activity. The results suggest that dark storage is recommended for a better physicochemical quality of Valeriana leaves. In particular, light influenced significantly the browning index and hue angle with a significance level of and , respectively, whereas both exposure conditions affected total bacterial count and pH ( ). Dipping treatments had an effect on pH, aw, and total bacterial count, while the storage time influenced with highly significant differences the most of the studied parameters, except for the antioxidant compounds.