Special Issue Information

Dear Colleagues,

In the last few years, microbiology has made great advancements through the next-generation sequencing (NGS) methods. Strains have been sequenced, making it possible to: compare phylogenetically the food associated strains; identifying Single Nucleotide Polymorphisms (SNPs) and relating their selection with the food environment and the selective pressure; and identifying CRISPR-Cas variable regions as an immune system that maintain trace of plasmids and bacteriophage infections. Bacterial communities have been studied with culture-dependent and culture-independent methods, and microbiomes have been analyzed in foods, environment, as well as in the gut. Novel food process technologies (microwave, Radio frequency energy) can thermally process food products by exploiting dielectric properties and water activity without using overly high temperatures. Food additives, such as bacteriocins, lactic and sorbic acid, and food preserving agents, are sought to ensure low costs and a high quality and safety of products. Novel phytochemicals may be found with good antibacterial activity.

We will consider any submissions associated with novel and advanced techniques and methodologies dealing with the microbiology of foods, and the processes relying on microorganisms (desired and unwanted, spoiling or toxin-producing, and delivering enzymes affecting the quality of productions), industrial challenges (fungal and bacterial containment), and solutions by food technologists in order to assure a production line. In the coming years, with a growing population, the food security challenge poses the problem of delivering enough commodities and foods, from raw materials to processed foods, and their stockage, and novel packaging solutions with shelf life extensions.

Dr. Palmiro Poltronieri
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Challenges is an international peer-reviewed open access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

Microbiological Analysis Methods
Metagenomics and Next Generation sequencing
Typing methods: AFLP, DGGE-PCR
CRISPR-Cas systems and bacteriophage immunity
Genotyping
microbial community and interactions
Starter strains
Non Starter Lactic Acid Bacteria
Phenotyping
Metabolite analysis
Food processing
Technologies for food Preservation and shelf-life extension
Food spoilage
Bactericins
bacteriostatic compounds and phytochemicals

Published Papers (2 papers)

Download All Papers

Review

Jump to: Other

2253 KiB

Open AccessReview

Challenges in Specialty Coffee Processing and Quality Assurance

by Palmiro Poltronieri and Franca Rossi

Challenges 2016, 7(2), 19; https://doi.org/10.3390/challe7020019 - 24 Oct 2016

Cited by 66 | Viewed by 27919

Abstract

Coffee is an important crop that assures a sustainable economy to farmers in tropical regions. A dramatic concern for coffee production is currently represented by climate change, which threatens the survival of Coffea arabica cultivation worldwide and imposes modifications of the agronomic practices to prevent this risk. The quality of coffee beans depends on optimized protocols of cultivation, ripe berries collection, and removal of the outer fruit layers by dry or wet processes and moisture reduction. Storage and shipment represent two steps where bean quality needs to be preserved by preventing fungal contamination that may impact the final product and form mycotoxins, mainly ochratoxin A. In this review, we describe the challenges faced by the coffee industry to guarantee quality from production to roasting and brewing. An overview of novel technologies, such as the application of starter cultures in fermentation and the exploitation of industrial enzymes in accelerating the process of flavour development in coffee beans, is given. Moreover, the results of studies on microbial populations on coffee and the differences found in fungi, yeasts and bacteria composition among the investigations, are summarized. In particular, this review describes new attempts to contain the development of mycotoxigenic fungi, through the application of antagonistic microorganisms such as S. cerevisiae. The new wave of specialty coffees, i.e., those with a cupping score higher than 85/100, is also presented. It is shown how, through careful coffee production methods and controlled fermentation processes, coffee producers may increase their income by assuring high standards of quality and high added value for the coffee experience sector. Full article

(This article belongs to the Special Issue Food Microbiology: Technologies and Processes, Microbiology Analysis Methods, and Antimicrobials)

► Show Figures

Figure 1

Other

Jump to: Review

1842 KiB

Open AccessBrief Report

Use of Bacteriocinogenic Cultures without Inhibiting Cheese Associated Nonstarter Lactic Acid Bacteria; A Trial with Lactobacillus plantarum

by Franca Rossi and Gianluca Veneri

Challenges 2016, 7(1), 4; https://doi.org/10.3390/challe7010004 - 14 Feb 2016

Cited by 3 | Viewed by 4883

Abstract

Bacteriocinogenic cultures can represent a natural way to increase the safety of cheeses made from raw milk, in which a relevant role in ripening and flavor formation is exerted by the nonstarter lactic acid bacteria (NSLAB). Since the latter can be inhibited by bacteriocin producers, this study evaluated to which extent a nisinogenic culture inoculated at low initial levels can affect the growth rate and peptide degradation activity of the nisin-sensitive cheese isolate Lactobacillus plantarum LZ by comparison with its isogenic variant, L. plantarum LZNI, with increased immunity to nisin. A growth delay of the nisin sensitive strain was observed only when its initial number was 100-fold lower than the nisin producer and nisin was added as an inducer of its own production. In this case, the amount of free α-amino groups was significantly different between cultures of L. plantarum LZ and LZNI only at Day 1. Reverse Phase High Performance Liquid Chromatography (RP-HPLC) highlighted a few differences between the peptide profiles of co-cultures L. plantarum LZ and LZNI. However, results showed that the bacteriocin producer did not dramatically influence the behavior of the sensitive NSLAB and that the evaluation of the effects on microbial contaminants in cheese is worthwhile. Full article

(This article belongs to the Special Issue Food Microbiology: Technologies and Processes, Microbiology Analysis Methods, and Antimicrobials)

► Show Figures