38 research outputs found
Control of Aspergillus niger with garlic, onion and leek extracts
Antifungal activity of “Allium” vegetables that is garlic (Allium sativum L.), onion (Allium cepa L.) and leek (Allium porrum L.) were investigated against Aspergillus niger. Minimal inhibitory concentrations (MIC) and minimal fungicidal concentrations (MFC) of aqueous, ethyl alcohol and acetone extracts were determined by disc diffusion and broth dilution methods in the test tubes. Onion extract with ethyl alcohol (275 mg/mL MFC), aqueous garlic extract (325 mg/mL MFC) and aqueous leek extract (900 mg/mL MFC) found the most inhibitory against A. niger
Bacterial cellulose-lactoferrin as an antimicrobial edible packaging
Bacterial cellulose (BC) films from two distinct sources (obtained by static culture with Gluconacetobacter xylinus ATCC 53582 (BC1) and from a commercial source (BC2)) were modified by bovine lactoferrin (bLF) adsorption. The functionalized films (BC+bLF) were assessed as edible antimicrobial packaging, for use in direct contact with highly perishable foods, specifically fresh sausage as a model of meat products. BC+bLF films and sausage casings were characterized regarding their water vapour permeability (WVP), mechanical properties, and bactericidal efficiency against two food pathogens, Escherichia coli and Staphylococcus aureus. Considering their edibility, an in vitro gastrointestinal tract model was used to study the changes occurring in the BC films during passage through the gastrointestinal tract. Moreover, the cytotoxicity of the BC films against 3T3 mouse embryo fibroblasts was evaluated.
BC1 and BC2 showed equivalent density, WVP and maximum tensile strength. The percentage of bactericidal efficiency of BC1 and BC2 with adsorbed bLF (BC1+bLF and BC2+bLF, respectively) in the standalone films and in inoculated fresh sausages, was similar against E. coli (mean reduction 69 % in the films per se versus 94 % in the sausages) and S. aureus (mean reduction 97 % in the films per se versus 36 % in the case sausages). Moreover, the BC1+bLF and BC2+bLF films significantly hindered the specific growth rate of both bacteria. Finally, no relevant cytotoxicity against 3T3 fibroblasts was found for the films before and after the simulated digestion. BC films with adsorbed bLF may constitute an approach in the development of bio-based edible antimicrobial packaging systems.The authors would like to acknowledge Portuguese Foundation
for Science and Technology (Fundação para a Ciência e Tecnologia)
for the research grants: Jorge Padrão SFRH/BD/64901/2009, Sara
Gonçalves SFRH/BD/63578/2009, João Pedro Silva SFRH/BPD/
64958/2009, Ana Cristina Pinheiro SFRH/BPD/101181/2014. V.
Sencadas thanks support from the COST Action MP1206: “Electrospun
nano-fibres for bio inspired composite materials and innovative
industrial applications” and MP1301: “New Generation
Biomimetic and Customized Implants for Bone Engineering”. The
authors would also like to thank the co-funded by the Programa
Operacional Regional do Norte (ON.2 e O Novo Norte), QREN,
FEDER Projects “BioHealth e Biotechnology and Bioengineering
approaches to improve health quality”, Ref. NORTE-07-0124-
FEDER-000027; “BioInd e Biotechnology and Bioengineering for
improved Industrial and Agro-Food processes”, REF. NORTE-07-
0124-FEDER-000028; Strategic Project PEST-C/FIS/UI607/2014;
Matepro eOptimizing Materials and Processes”, ref. NORTE-07-
0124-FEDER-000037; Strategic Project PEst-OE/EQB/LA0023/2013
and project ref. RECI/BBB-EBI/0179/2012 (project number FCOMP-
01-0124-FEDER-027462). Finally, the authors thank the Fundação
para a Ciência e Tecnologia for the strategic funding from the UID/
BIO/04469/2013 unit
Antimicrobial activity of the essential oil of Cymbopogon citratus (DC) Stapf. on Staphylococcus spp., Streptococcus mutans and Candida spp.
Medicinal plants with fungicide action, antibacterial and anti-inflammatory effects are under investigation. The main purpose of this work was to evaluate the antimicrobial activity of the essential oil from Cymbopogon citratus (DC) Stapf. on strains of Staphylococcus spp., Streptococcus mutans and Candida spp. with planktonic and biofilm growth. To study the micro-organisms in planktonic cells, the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined by using 9 clinical strains for each species and 1 ATCC (American Type Culture Collection) from C. albicans, C. tropicalis, C. glabrata, S. aureus, S. epidermidis and S. mutans. In order to evaluate the effects of the essential oils on biofilms, strains of S. aureus (ATCC 6538), S. mutans (ATCC 35688) and C. albicans (ATCC 18804) were used. The biofilm was formed on acrylic resin discs with isolated micro-organisms or in associations. The number of colony-forming-units (CFU) obtained in each biofilm (CFU/ml) was submitted to Student's t statistical test. The results demonstrated that the essential oil of Cymbopogon citratus showed microbiostatic and microbicidal activity against all tested strains. The average CFU/ml for the biofilm of S. aureus, S. mutans and C. albicans, whether isolated or in association, was lower in the group treated with essential oil than in the control group
Novel food packaging systems with natural antimicrobial agents
A new type of packaging that combines food packaging materials with antimicrobial substances to control microbial surface contamination of foods to enhance product microbial safety and to extend shelf-life is attracting interest in the packaging industry. Several antimicrobial compounds can be combined with different types of packaging materials. But in recent years, since consumer demand for natural food ingredients has increased because of safety and availability, these natural compounds are beginning to replace the chemical additives in foods and are perceived to be safer and claimed to alleviate safety concerns. Recent research studies are mainly focused on the application of natural antimicrobials in food packaging system. Biologically derived compounds like bacteriocins, phytochemicals, enzymes can be used in antimicrobial food packaging. The aim of this review is to give an overview of most important knowledge about application of natural antimicrobial packagings with model food systems and their antimicrobial effects on food products. © 2015, Association of Food Scientists & Technologists (India)
Control of Listeria monocytogenes in ground chicken breast meat under aerobic, vacuum and modified atmosphere packaging conditions with or without the presence of bay essential oil at 4°C
In this study the combined effect of bay (Laurus nobilis L.) essential oil (0.5% v/w) with modified atmosphere (MAP) (20%CO2/80%N2) and vacuum packaging in ground chicken breast meat stored at 4°C was investigated. Microbial populations of inoculated Listeria monocytogenes AUFE 39237 in chicken meat and Escherichia coli and total viable counts (TVC) were also monitored during 0,1,3,5,7th days of storage. MAP packaging with/without bay oil gave significantly (p<0.01) higher reductions of microbial populations. Vacuum packaging and bay oil combination was also found significantly effective (p<0.01) against E. coli in ground chicken meats. The preservative effect of MAP and vacuum packaging against some food pathogens can be increased with bay essential oil in chicken meats
COMPETITIVE STRATEGIES OF FRUIT AND VEGETABLE PROCESSING INDUSTRY IN TURKEY
Fruit and vegetable processing industry is very important for Turkey regarding both the internal and the external market. A review of Turkish agricultural history shows that dramatic changes have occurred in fruit and vegetable industry. It seems evident that changes will continue for the coming years. Especially developments of South Marmara Regions fruit and vegetable processing industry provide a good example for the agri-food sector. Today, consumer preferences drive markets. Reshape of the international agricultural trade is required due to, mainly, the globalisation of the markets. This will give growers more competition and the issues of marketing, international trade, environmental protection and government policies will be important factors for them. The aim of this study it to examine the current situation of Turkish fruit and vegetable processing industry and highlight some points for the competitiveness of the industry. SWOT analysis was applied regarding the product quality, consumption, production, imports, exports and structure of market competition and distribution aspects
The Effect of Modified Atmosphere and Vacuum Packaging on the Physicochemical, Microbiological, Sensory and Textural Properties of Crottin de Chavignol Cheese
In this work, it was aimed to determine the effect of packaging technique on some quality properties of Crottin de Chavignol type goat cheese packaged under vacuum (VP) and modified atmosphere (MAP) (%20 CO2 + %80 N-2) during storage at + 4 degrees C and also to compare these two packaging techniques to be able determine the more suitable packaging technique for Crottin de Chavignol type goat cheese. Sampling was carried out for physicochemical, microbiological, sensory and textural analyses at 1(st) day, 3(rd), 6(th), 9(th), 12(th) and 15(th) weeks. Control cheeses which were packaged under atmospheric air were unacceptable sensorially at 3(rd) week due to their visible mould growth. Both modified atmosphere and vacuum packaging had favourable effects on physicochemical properties, microbiological properties, color, sensory attributes of Crottin de Chavignol type goat cheese to longer the shelf life of cheese. According to the results of our study, at 15(th) weeks mould growth increased to 2.3 log cfu/g and 3.8 log cfu/g at MAP and NIP cheese samples respectively whereas the mould growth was > 1 log cfu/g at 1.day of storage. And the taste scores of VP cheese samples were below acceptability limit at 15(th) weeks because of formation of oxidized flavour. The packaging type whether MAP or VP didn't significantly affected the pH, dry matter, color and textural properties except hardness, chewiness and gumminess. Hardness, chewiness and gumminess values of VP cheeses were higher than MAP cheese samples
