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Italy is the second largest producer in the world of olive oil, preceded only by Spain. Although olive oil can be considered as a “green gold” all over the world, the treatment of its by-products is a critical aspect to cope with. Indeed, the polluting character of such by-product together with its high costs for an effective disposal strongly penalize the olive oil industry. In particular, 50 % of oil production costs depend on its waste disposal. In this context, the aim of this work was to evaluate a potential exploitation of olive pomace as a feedstock for the production of flavours of interest for the food industry.

Within this research, the suitability of Squacquerone cheese to support the viability of Lactobacillus crispatus BC4, a vaginal strain endowed with a strong antimicrobial activity against urogenital pathogens and foodborne microorganisms, in order to recommend a gender food for woman wellbeing, was investigated. The viability of L. crispatus BC4, used as adjunct culture in the production of a functional cheese, was evaluated during the product refrigerated storage, also when Squacquerone cheese was subjected to simulated stomach-duodenum passage. Moreover, the effects of the probiotic strain addition were evaluated on product pattern profiles, in terms of proteolysis, lipolysis and volatile molecule profiles. The data obtained underlined that L. crispatus BC4 maintained high viability, also in presence of physiological stress conditions, until the end of the refrigerated storage. Moreover, the inclusion of L. crispatus BC4 gave raise to cheese products with higher score of overall acceptability when compared to control cheese. Moreover, the survival of L. crispatus BC4, carried in Squacquerone cheese, was verified by the patented Simulator of the Human Intestinal Microbial Ecosystem (SHIME). The results highlighted that the vaginal Lactobacillus was initially affected by the low pH in the stomach, simulated by the reactor of the SHIME in fed state, while it was resistant to bile salts and pancreatic juices. Although only in vivo trials can confirm the functionality of the produced cheese in vagina environment, these data represent a further tassel to use the Squacquerone cheese produced as gender dietary strategy for woman well-being. These results suggest that the obtained cheese could represent not only a gender strategy to prevent vaginal dysbiosis, but also a challenge to improve the dairy sector. The research was supported by a grant obtained at the University of Bologna (Italy), within the Alma Idea Project “Approcci biotecnologici per la produzione di un alimento di genere - Biotechnological approaches to produce a gender food”.

Citrus cultivation is one of the most important agricultural sectors in the world and the main uses of these products are the market of fresh produce and the production of juices, pulps, purees, jams and ready-to-eat salads. The citrus processing by-product mainly contains water and many compounds which can have remarkable biological properties, and can therefore be considered as a source of high.value substances, a source of fiber and antioxidants

The aim of this work was to assess if a sub-lethal high pressure homogenization (HPH) treatment could modulate in vitro functional and biological properties of probiotic bacteria. Lactobacillus paracasei A13, Lactobacillus acidophilus 08 and Dru, Lactobacillus delbrueckii subsp. lactis 200 and bile-resistant derivatives L. acidophilus Druþ and L. delbrueckii subsp. lactis 200þ were suspended in phosphate buffered saline solution and treated at 50 MPa. Data obtained showed that HPH can modulate hydrophobicity and auto-aggregation without modification of viability and decarboxylase activity. Resistance to simulated gastric conditions resulted strain-dependent. High resistance was observed for treated L. paracasei A13, L. acidophilus Dru and 08 and L. delbrueckii subsp. lactis 200. The HPH-treatment reduced the resistance to simulated stomach duodenum-passage of L. acidophilus Dru while increased it for L. paracasei A13. Strain viability and resistance to simulated gastric conditions were evaluated treating at 50 MPa cells suspended in acidified buttermilk (pH 4.6) and stored at 4 C for 30 days. The highest cell viability loss, after 30 d of refrigerated storage, was observed for L. acidophilus Dru, independently of the application of HPH. However, after 30 days of storage, the resistance of L. paracasei A13 to simulated gastric digestion significantly increased in HPH treated cells. Fil: Tabanelli, G.. Interdipartimental Center of Industrial Research (CIRI Agroalimentare); Italia Fil: Patrignani, F.. Universidad de Bologna; Italia Fil: Vinderola, Celso Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Lactología Industrial. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Lactología Industrial; Argentina Fil: Reinheimer, Jorge Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Lactología Industrial. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Lactología Industrial; Argentina Fil: Gardini, F.. Universidad de Bologna; Italia Fil: Lanciotti, R.. Universidad de Bologna; Italia

This study focuses on the isolation of lactobacilli/bifidobacteria from human breast milk and their first characterization, in the perspective to find new probiotic candidates to be included in food products. More specifically, breast-milk-isolated strains demonstrated a very good aptitude to adhere to intestinal cells, in comparison with L. rhamnosus GG strain, taken as reference. The same behavior has been found for hydrophobicity/auto-aggregation properties. A remarkable antagonistic activity was detected for these isolates not only against spoilage and pathogenic species of food interest, but also against the principal etiological agents of intestinal infections. Indeed, isolated strains impaired spoilage and pathogenic species growth, as well as biofilm formation by gut pathogens. In addition, breast milk strains were characterized for their antibiotic susceptibility, displaying species-specific and strain-specific susceptibility patterns. Finally, to assess their technological potential, the fermentation kinetics and viability of breast milk strains in pasteurized milk were investigated, also including the study of the volatile molecule profiles. In this regard, all the strains pointed out the release of aroma compounds frequently associated with the sensory quality of several dairy products such as acetic acid, diacetyl, acetoin, acetaldehyde. Data here reported point up the high potential of breast-milk-isolated strains as probiotics.

Background Yarrowia lipolytica is one of the most studied “non-conventional” yeasts. Due to its intrinsic biological characteristics and variability, the potential applications of wild type yeasts in the agri-food sector are broad (production of biomasses, enzymes, and metabolites). By-products generated by the food industry are rising environmental and economic concerns worldwide. These side streams have different compositions and stability. However, they can still be applied as substrates for microbial growth. Scope and approach The fitness of wild type strains to adverse and different environments can be exploited not only for food production but also for recovery and valorization of agri-food wastes and by-products. This review brings together a selection of the most relevant and recent data about the physiology, nutritional requirements, and metabolites produced in wild type isolates of Y. lipolytica. Moreover, the principal agri-food side streams, their specific productions and valorization using wild type strains have been critically discussed. Key finding and conclusions Critical aspects of the side streams and by products can be resolved (e.g. reduction of COD and pollutants before discharging), novel ingredients can be generated (e.g. lipases, single cell oils and citric acid) and, eventually, yeast biomass can be produced for further applications (adjunct or food supplements). Selecting and characterizing wild type isolates able to consume or convert or valorize the different waste/by-product components into added value products is extremely important in the view of a sustainable process and sustainable economy.

Modified atmosphere packaging (MAP) is an efficient method to increase shelf-life of fishery products by inhibiting bacterial growth and oxidative reactions. Beside the traditional gases used for MAP, novel gases such as argon (Ar) and nitrous oxide (N2O) were approved for food use in the European Union. The present research investigates the effect of MAP with unconventional gas mixtures, that previously positively affected microbial shelf-life, on colour, lipid oxidation and sensorial characteristics of sardine fillets during storage. Four atmosphere conditions were tested: Air (20.8% O2/79.2% N2), N2 (30% CO2/70% N2), N2O (30% CO2/70% N2O) and Ar (30% CO2/70% Ar). Samples were stored for 12days at 3°C. Results showed that the removal of oxygen significantly inhibited the oxidation process; however, most of the investigated parameters related to fat oxidation did not show any improvement, except for a slight decrease in lipid hydrolysis and improvement in sensory properties in the packaging containing Ar.

Pathogenic fungi belonging to the genera Botrytis, Phaeomoniella, Fusarium, Alternaria and Aspergillus are responsible for vines diseases that affect the growth, grapevine yield and organoleptic quality. Among innovative strategies for in-field plant disease control, one of the most promising is represented by biocontrol agents, including wild epiphytic yeast strains of grapevine berries. Twenty wild yeast, isolated and molecularly identified from three different Malaysian regions (Perlis, Perak and Pahang), were evaluated in a preliminary screening test on agar to select isolates with inhibition against Botrytis cinerea. On the basis of the results, nine yeasts belonging to genera Hanseniaspora, Starmerella, Metschnikowia, Candida were selected and then tested against five grape berry pathogens: Aspergillus carbonarius, Aspergillus ochraceus, Fusarium oxysporum, Alternaria alternata and Phaeomoniella chlamydospora.Starmerella bacillaris FE08.05 and Metschnikowia pulcherrima GP8 and Hanseniaspora uvarum GM19 showed the highest effect on inhibiting mycelial growth, which ranged between 15.1 and 4.3 mm for the inhibition ring. The quantitative analysis of the volatile organic compound profiles highlighted the presence of isoamyl and phenylethyl alcohols and an overall higher presence of low-chain fatty acids and volatile ethyl esters. The results of this study suggest that antagonist yeasts, potentially effective for the biological control of pathogenic moulds, can be found among the epiphytic microbiota associated with grape berries.

Ethyl carbamate (EC), a genotoxic and carcinogenic compound in soy sauce accumulated during thermal processes, has raised public health concern for its multipoint potential carcinogenic risk to human. In this work, based on the analysis of EC accumulation during thermal processes of soy sauce, ornithine and quercetin were added before thermal processes to reduce EC accumulation. A reduction rate of 23.7–63.8% in simulated solution was founded. Kinetic studies indicated that ornithine was a byproduct of alcoholysis reaction when EC formed, while quercetin could compete with the precursor ethanol and react with carbamyl compounds, which therefore prevented EC accumulation. A maximum of 47.2% decrease of EC in soy sauce was achieved, and no remarkable changes in volatile compounds profile and color of soy sauce were found. In conclusion, the addition of quercetin and ornithine before thermal processes may be preferable for the controlling of EC content in soy sauce.

Lamiaceae (Labiatae) are an important group of medicinal plants, which have been used for treating heart disease in traditional medicine for centuries. These mainly aromatic plants are used as essential oils, extracts or isolated components (polyphenols, phenolic compounds, terpenes, iridoids etc.). Some Labiatae species (more than 30, such as cornmint, lavender, patchouli, rosemary etc.) are famous for their use in essential oil production worldwide. In this review, cardioprotective effects of Lamiaceae and their active secondary metabolites, as well as mechanism of action against cardiovascular diseases (hypertension, angina pectoris, hyperlipidemia, thromboembolism, coronary heart disease, heart failure, venous insufficiency, arrhythmia) will be discussed. Use of Labiatae as food or food additives (such as spices) may prevent risk of cardiovascular diseases, diabetes and cancer. This approach is also described as a part of the article. Studies on developing new, effective and safe natural products from Lamiaceae (rich source of flavonoids and other active compounds) are promising and may offer prevention and treatment for patients with coronary disease and other related diseases.

Simple Summary This study investigates the potential of a nisin producer, i.e., Lactococcus lactis strain, in the making of Squacquerone cheese. The finding of this research indicates that the tested Lactococcus lactis strain represents a suitable candidate to be used as adjunct culture in Squacquerone cheesemaking since it improved the safety and sensory quality of the product without negatively affecting rheological characteristics and proteolysis. Abstract This research investigated the technological and safety effects of the nisin Z producer Lactococcus lactis subsp. lactis CBM 21, tested as an adjunct culture for the making of Squacquerone cheese in a pilot-scale plant. The biocontrol agent remained at a high level throughout the cheese refrigerated storage, without having a negative influence on the viability of the conventional Streptococcus thermophilus starter. The inclusion of CBM 21 in Squacquerone cheesemaking proved to be more effective compared to the traditional one, to reduce total coliforms and Pseudomonas spp. Moreover, the novel/innovative adjunct culture tested did not negatively modify the proteolytic patterns of Squacquerone cheese, but it gave rise to products with specific volatile and texture profiles. The cheese produced with CBM 21 was more appreciated by the panelists with respect to the traditional one.

Sub-lethal high-pressure homogenization treatments applied to Lactobacillus paracasei A13 demonstrated to be a useful strategy to enhance technological and functional properties without detrimental effects on the viability of this strain. Modification of membrane fatty acid composition is reported to be the main regulatory mechanisms adopted by probiotic lactobacilli to counteract high-pressure stress. This work is aimed to clarify and understand the relationship between the modification of membrane fatty acid composition and the expression of genes involved in fatty acid biosynthesis in Lactobacillus paracasei A13, before and after the application of different sub-lethal hyperbaric treatments. Our results showed that Lactobacillus paracasei A13 activated a series of reactions aimed to control and stabilize membrane fluidity in response to high-pressure homogenization treatments. In fact, the production of cyclic fatty acids was counterbalanced by the unsaturation and elongation of fatty acids. The gene expression data indicate an up-regulation of the genes accA, accC, fabD, fabH and fabZ after high-pressure homogenization treatment at 150 and 200 MPa, and of fabK and fabZ after a treatment at 200 MPa suggesting this regulation of the genes involved in fatty acids biosynthesis as an immediate response mechanism adopted by Lactobacillus paracasei A13 to high-pressure homogenization treatments to balance the membrane fluidity. Although further studies should be performed to clarify the modulation of phospholipids and glycoproteins biosynthesis since they play a crucial role in the functional properties of the probiotic strains, this study represents an important step towards understanding the response mechanisms of Lactobacillus paracasei A13 to sub-lethal high-pressure homogenization treatments.

Lactic acid bacteria (LAB) and probiotics have been used for a long time as starter cultures and functional adjuncts for the production of fermented functional foods and beverages. In fact, throughout sustainable fermentation processes, they can increase the food product safety and improve shelf life, at the same time, also food nutritional, organoleptic, technological, and functional properties. The proper use of microbial cultures can enhance the added value of specific fermented foods increasing the bioavailability of bioactive compounds (antioxidant compounds, functional peptides, unsaturated long-chain fatty acids etc.), having a positive biological role on human health. On the other hand, the selection of tailor-made starter and functional cultures can increase the gamma of specific foods for specific consumer's category. Thus, in this scenario, this chapter is aimed to give an overview on the applicative potentialities of LAB, used as starters or functional adjuncts, and to increase functionality of fermented dairy products and beverages, increasing also the sustainability of the entire considered processes.

The present research was aimed to investigate the potentialities of ultra high pressure homogenization (UHPH) to produce stable natural antimicrobial based nanoemulsions. Initially, the nanoemulsions were characterized for their size, stability over time and antimicrobial properties against several pathogenic and spoilage microorganisms. After that nanoemulsions were tested to increase the safety and shelf-life of apple juice deliberately inoculated with pathogenic (Listeria monocytogenes Scott A, Staph. aureus SR231, Escherichia coli 555) and spoilage microorganisms (Saccharomyces cerevisiae SPA, Lactobacillus plantarum 82) and treated with different high pressure homogenization treatments. The analyses performed by dynamic laser light scattering showed that the hexanal and trans-2-hexenal based nanoemulsions were characterized by an average size of 86 and 100 nm, respectively while they were characterized by a stability, over time, of 14 months without separation. Moreover, the nanoemulsions resulted, after the UHPH treatment, colourless. The pathogenic species deliberately inoculated in apple juice decreased their cell loads with different kinetics in relation to the use of hexanal and trans-2-hexenal and high pressure homogenization treatment applied. Regarding spoilage microorganisms, S. cerevisiae cell loads decreased under detection limit (1 log CFU/mL) in juice containing nanoemulsions and treated at 200 MPa for 2 cycles. The data of the present research contribute to support the application of natural antimicrobial based nanoemulsions into complex food system, enlarging the experimental evidence for their use in food sector. In particular, the obtained hexanal and tran-2-hexenal based nanoemulsions have demonstrated great application, due also to their organoleptic compatibility, to the fruit juice sector, promoting also an increase of quality of apple juice.

AIMS: The application of essential oils and their components as food preservatives is promising but requires a deeper understanding of their mechanisms of action. This study aims to evaluate the effects of thyme essential oil, carvacrol, citral and 2-(E)-hexenal, on whole-genome gene expression (the transcriptome), as well as the fatty acids composition of the cell membranes of Escherichia coli K12.METHODS AND RESULTS: Therefore, we studied the response against 1 hour of exposure to sublethal concentrations of natural antimicrobials, of exponentially growing Escherichia coli K12, using DNA microarray technology and a gas chromatographic method. The results show that treatment with a sublethal concentration of the antimicrobials strongly affects global gene expression in E. coli for all antimicrobials used. Major changes in the expression of genes involved in metabolic pathways as well as in fatty acid biosynthesis and protection against oxidative stress were evidenced. Moreover, the sub-lethal treatments resulted in increased levels of unsaturated and cyclic fatty acids as well as an increase of the chain length compare to the controls.CONCLUSIONS: The down-regulation of genes involved in aerobic metabolism indicate a shift from respiration to fermentative growth. Moreover, the results obtained suggest that the cytoplasmic membrane of E. coli is the major cellular target of essential oils and their components. In addition, the key role of membrane unsaturated fatty acids in the response mechanisms of E. coli to natural antimicrobials has been confirmed in this study.SIGNIFICANCE AND IMPACT OF THE STUDY: The transcriptomic data obtained signify a further step to understand the mechanisms of action of natural antimicrobials also when sub-lethal concentrations and short term exposure. In addition, this research goes in deep correlating the transcriptomic modification with the changes of E. coli fatty acid composition of cell membrane identified as the main target of the natural antimicrobials. This article is protected by copyright. All rights reserved.

Present study aimed to ascertain whether the combination of two factors, i.e., time of harvest and type of yeast, can significantly moderate the effect of climate change on Chardonnay wine composition. In this view, three Chardonnay musts obtained from grapes at different harvest date [technological maturity ‘as control’; delayed harvest; a mixture of ‘early (green) harvest’ with delayed harvest ‘as alternative approach’] and three selected yeast strains [Saccharomyces cerevisiae ‘as control’; hybrid Saccharomyces cerevisiae/Saccharomyces paradoxus; scalar alternative approach with Starmerella bacillaris and hybrid Saccharomyces cerevisiae/Saccharomyces paradoxus] were used to design and compare six different trials, replicated at pilot level (n. total fermentations: 18). Wines were evaluated in terms of sensory and chemical parameters (alcohol, acidity, organic acids, phenolic compounds and glycerol) and results tested by statistical analysis. Although the wine alcohol content decreased at the best by ~ 1.2% v/v, whereas the total acidity increased up to ~ 2.5 g/L, the results from sensory evaluation highlighted that the proposed ‘alternative approach’ may cause excessive acidity and bitterness perception, therefore, further deacidification and fining treatments may be needed. The present approach to reduce the alcohol content of wine and increase its total acidity is simple, inexpensive and applicable in all wineries.