Search results for "microbial"
showing 10 items of 2041 documents
An innovative method to produce green table olives based on "pied de cuve" technology
2015
The technology of “pied de cuve” (PdC) is applied in food process only to produce wines with an enriched community of pro-technological yeasts. PdC promotes the growth of the desirable microbial strains in a small volume of grape must acting as a starter inoculums for higher volumes. The aim of the present work was to investigate the use of partially fermented brines, a technology known as PdC, developed with lactic acid bacteria (LAB) on the microbiological, chemical and sensory characteristics of green fermented table olives during two consecutive campaigns. The experimental plan included two trials based on different PdCs: trial A, PdC obtained with Lactobacillus pentosus OM13; trial B, …
The coffee-machine bacteriome: biodiversity and colonisation of the wasted coffee tray leach
2015
AbstractMicrobial communities are ubiquitous in both natural and artificial environments. However, microbial diversity is usually reduced under strong selection pressures, such as those present in habitats rich in recalcitrant or toxic compounds displaying antimicrobial properties. Caffeine is a natural alkaloid present in coffee, tea and soft drinks with well-known antibacterial properties. Here we present the first systematic analysis of coffee machine-associated bacteria. We sampled the coffee waste reservoir of ten different Nespresso machines and conducted a dynamic monitoring of the colonization process in a new machine. Our results reveal the existence of a varied bacterial community…
Modelling the effect of ascorbic acid, sodium metabisulphite and sodium chloride on the kinetic responses of lactic acid bacteria and yeasts in table…
2010
he goal of this work was to apply the Quasi-chemical primary model (a system of four ordinary differential equations that derives from a hypothetical four-step chemical mechanism involving an antagonistic metabolite) in the study of the evolution of yeast and lactic acid bacteria populations during the storage of Manzanilla–Aloreña table olives subjected to different mixtures of ascorbic acid, sodium metabisulphite and NaCl. Firstly, the Quasi-chemical model was applied to microbial count data to estimate the growth–decay biological parameters. The model accurately described the evolution of both populations during storage, providing detailed information on the microbial behaviour. Secondly…
Microbial inactivation and evaluation of furan formation in high hydrostatic pressure (HHP) treated vegetable-based infant food.
2017
Abstract The inactivation of pathogenic and spoilage bacteria as well as the formation of food processing contaminants (e.g. acrylamide, furan, etc.) in infant foods is of utmost importance for industry, consumers as well as regulatory bodies. In this study, the potential of high hydrostatic pressure (HHP) for microorganism inactivation including total mesophilic aerobic bacteria (TMA) and total yeasts and molds (TYM) at equivalent processing conditions, as well as its effects on furan formation in vegetable-based infant food was evaluated. The process parameters evaluated were combinations of pressures (200, 300, and 400 MPa), temperatures (25, 35, and 45 °C), and treatment times (5, 10, a…
Microbial Ecology of Retail Ready-to-Eat Escarole and Red Chicory Sold in Palermo City, Italy
2019
Background: Ready-To-Eat (RTE) foods include any edible food that is commonly consumed raw. This study aimed at evaluation of microbial ecology of retail RTE escarole and red chicory sold in Palermo city, Italy. Methods: A total of 32 mono-varietal RTE samples, including escarole (n=16) and red chicory (n=16) samples were obtained from Palermo, Italy. Both RTE vegetables at expiry date were analyzed to quantify spoilage bacteria, pathogenic bacteria, and yeast. All different colonies were isolated and identified on the basis of phenotypic characteristics and genetic polymorphisms by random amplification of polymorphic DNA-Polymerase Chain Reaction (PCR) and further genotype by sequencing th…
Ultrasound as a preservation technique
2021
Abstract The application of ultrasound offers a wide range of possibilities in food preservation, especially when it is used combined with heat or other preservation treatments (natural antimicrobials). In this chapter, some relevant studies dealing with the impact of the ultrasound alone and/or combined with other preservation techniques on microbial inactivation from different food groups (fruits and vegetables, milk and derived products as well as fish and meat) will be discussed. In addition, some findings regarding the effects of ultrasound on nutritional and physicochemical properties of the products will be also presented.
Application of plant extracts to improve the shelf-life, nutritional and health-related properties of ready-to-eat meat products.
2018
Plant extracts are increasingly becoming important additives in food industry due to their antimicrobial and antioxidant abilities that delay the development of off-flavors and improve the color stability in ready-to-eat (RTE) meat products. Due to their natural origin, they are excellent candidates to replace synthetic molecules, which are generally considered to have toxicological and carcinogenic effects. The efficient extraction of these antioxidant molecules from their natural sources, along with the determination of their activity in the commercialized products, have been a great challenge for researchers and food chain contributors. The objective of this review is to highlight the ap…
An overview of the potential applications based on HPP mechanism
2020
Abstract Over the last decades, high-pressure processing (HPP) has shown its potential as one of the most relevant technologies for nonthermal food processing mainly due to its application for microbial inactivation while retaining fresh-like characteristics of the food. Moreover, HPP can be considered as a potential tool for developing new food products with new sensorial and functional properties. Apart from food preservation, the application of HPP to improve health attributes (e.g., reducing food contaminants or salt concentration), and to enhance the extraction or fermentation processes, has been an interesting research topic around the world. This chapter intends to show the core-base…
Assessment of contamination of Salmonella spp. in imported black pepper and sesame seed and salmonella inactivation by gamma irradiation
2021
This study shows the frequency of seeds samples contaminated by Salmonella spp. collected randomly from local markets; on 30 black pepper sample no contaminated sample was found while Salmonella spp. was detected in 3 of 36 (8.3%) analyzed sesame samples; three different serotypes were identified: S. Montevideo, S. Stanleyville e S. Tilene. The efficacy of gamma irradiation to inactivate Salmonella Montevideo in black pepper and sesame irradiated between 1 and 5 kGy was evaluated. 3 kGy is sufficient to reduce of 3-4 log CFU/g; whereas 5 kGy have been need to reduce 5.5-6 log CFU/g for samples of black pepper and sesame. No statistically significant differences were found between black pepp…
Inactivation of dried spores of Bacillus subtilis 168 by a treatment combining high temperature and pressure
2019
International audience; Specific treatments combining high temperatures of up to 150 °C and moderate pressure of up to 0.6 MPa have been applied to Bacillus subtilis 168 spores conditioned at different aw levels (between 0.10 and 0.70) corresponding to different residual water contents within the spore core. The spores were treated as a dry powder in a pressurized nitrogen environment or in water/glycerol solutions.These thermodynamic conditions were intended to prevent any water evaporation from the spore core during time/temperature treatments.Our results clearly show that retaining liquid water in the core by applying pressure during the treatment resulted in greater spore destruction (b…