Whey fermented by using Lactobacillus plantarum strains: A promising approach to increase the shelf life of pita bread

Nowadays, there is an increasing concern regarding the shelf life of food products, leading producers to research natural antimicrobial agents to use in food preparation. In this study, we evaluated the antifungal activity of Lactobacillus plantarum fermented whey and then added the whey during preparation of pita bread to study shelf-life improvement. The fermented whey showed a satisfactory inhibitory (antifungal) effect against Penicillium expansum and Penicillium brevicompactum strains: the minimum inhibitory and minimum fungicidal concentrations ranged from 3.9 to 39.0 g/L and from 62.5 to 250 g/L, respectively. Addition of fermented whey increased the shelf life of the pita bread. After inoculation of the bread surface with Penicillium, an increase in shelf life until d 8 was achieved compared with the positive control, whereas under natural contamination conditions, an extension of shelf life until d 19 was observed. In terms of antimicrobial activity, the greatest reduction (100%) in fungal growth was achieved when all of the water in the dough was replaced with fermented whey. An untrained sensory panel could not identify differences between bread produced with fermented whey and control pita breads. These results suggest the possibility of using fermented whey in food preservation

The soluble dietary fiber inulin can influence the bioaccessibility of enniatins

Enniatins (ENs) are bioactive compounds produced by the secondary metabolism of several Fusarium strains and are known to have various biological activities, such as acting as enzyme inhibitors, antifungal antibacterial agents, and immunomodulatory substances. This study investigated the bioaccessibility of the ENs in wheat crispy breads produced with three different inulin concentrations (1, 5 and 10%). The mean bioaccessibility data of the four ENs (A, A1, B and B1) ranged from 68.67% to 84.67 in the experiments carried out without inulin, whereas the data ranged from 51.00 to 74.00% in the experiments carried out with the wheat crispy bread produced with 5 and 10% of the inulin

Recovery of bioactive compounds from walnut ( Juglans regia L.) green husk by supercritical carbon dioxide extraction

In this work, the use of supercritical carbon dioxide, a nontoxic solvent, was proposed to extract bioactive compounds from Juglans regia L. green husk and was compared to other traditional techniques based on solvents such as ethanol, methanol and water. Supercritical CO2 was combined with ethanol as an organic modifier at a rate of 20% of the total flow to achieve greater extraction of polar compounds. The extracts were characterised in terms of extraction yields, antioxidant activity, total polyphenol content, phenolic acids, juglone, volatile organic compounds and antifungal activity. The results showed that the extracts obtained with supercritical CO2 were rich in polyphenols (10750 mg GAE/100 g) and juglone (1192 mg/100 g) and exerted high antioxidant activity and antifungal activity compared with the tested fungi. Walnut green husk is not just a food industry waste but also an important economic source of bioactive compounds that could be used for food active packaging

Potential application of lactic acid bacteria in the biopreservation of red grape from mycotoxigenic fungi

BACKGROUND: Filamentous fungi are the main contamination agent in the viticultural sector. Use of synthetic fungicides is theregular answer to these contaminations. Nevertheless, because of several problems associated with the use of synthetic com-pounds, the industry demands new and safer methods. In the present work, the biopreservation potential of four lactic acidbacteria (LAB) strains was studied against the principal grape contaminant fungi.RESULTS: Agar diffusion test evidenced that all four culture-free supernatant (CFS) had antifungal properties against all testedfungi. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) test values evidenced thatmedia fermented by theLactobacillus plantarumE3 andLactobacillus plantarumE4 strains showed the highest antifungal activ-ity, resulting in an MFC from 6.3 to 100 g L−1. Analysis of CFS evidenced the presence of different antifungal compounds, suchas lactic acid, phenyllactic acid and pyrazines. In tests on red grapes, an average reduction of 1.32 log10of the spores per gramof fruit was achieved by all CFS in grapes inoculated withAspergillus ochraceusand by 0.94 log10forL. plantarumE3 CFS againstBotrytis cinerea.CONCLUSION: The antifungal activity of the fermented CFS byL. plantarumE3 reduced the growth ofB. cinereaandA. ochraceusin grapes, which are the main contaminant and main producer of ochratoxin A in these crops, respectively. Therefore, based onthe results obtained in this work, use of the strainL. plantarumE3 could be an interesting option for the biopreservation ofgrapes

Bioaccessibility study of aflatoxin B1 and ochratoxin A in bread enriched with fermented milk whey and/or pumpkin

The presence of mycotoxins in cereals and cereal products remains a significant issue. The use of natural ingredients such as pumpkin and whey, which contain bioactive compounds, could be a strategy to reduce the use of conventional chemical preservatives. The aim of the present work was to study the bioaccessibility of aflatoxin B1 (AFB1) and ochratoxin (OTA) in bread, as well as to evaluate the effect of milk whey (with and without lactic acid bacteria fermentation) and pumpkin on reducing mycotoxins bioaccessibility. Different bread typologies were prepared and subjected to an in vitro digestion model. Gastric and intestinal extracts were analyzed by HPLC-MS/qTOF and mycotoxins bioaccessibility was calculated. All the tested ingredients but one significantly reduced mycotoxin intestinal bioaccessibility. Pumpkin powder demonstrated to be the most effective ingredient showing significant reductions of AFB1 and OTA bioaccessibility up to 74% and 34%, respectively. Whey, fermented whey, and the combination of pumpkin-fermented whey showed intestinal bioaccessibility reductions between 57-68% for AFB1, and between 11-20% for OTA. These results pointed to pumpkin and milk whey as potential bioactive ingredients that may have promising applications in the bakery industry

Potential application of lactic acid bacteria in the biopreservation of red grape from mycotoxigenic fungi

BACKGROUND: Filamentous fungi are the main contamination agent in the viticultural sector. Use of synthetic fungicides is the regular answer to these contaminations. Nevertheless, because of several problems associated with the use of synthetic compounds, the industry demands new and safer methods. In the present work, the biopreservation potential of four lactic acid bacteria (LAB) strains was studied against the principal grape contaminant fungi. RESULTS: Agar diffusion test evidenced that all four culture-free supernatant (CFS) had antifungal properties against all tested fungi. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) test values evidenced that media fermented by the Lactobacillus plantarum E3 and Lactobacillus plantarum E4 strains showed the highest antifungal activity, resulting in an MFC from 6.3 to 100 g L−1 . Analysis of CFS evidenced the presence of different antifungal compounds, such as lactic acid, phenyllactic acid and pyrazines. In tests on red grapes, an average reduction of 1.32 log10 of the spores per gram of fruit was achieved by all CFS in grapes inoculated with Aspergillus ochraceus and by 0.94 log10 for L. plantarum E3 CFS against Botrytis cinerea. CONCLUSION: The antifungal activity of the fermented CFS by L. plantarum E3 reduced the growth of B. cinerea and A. ochraceus in grapes, which are the main contaminant and main producer of ochratoxin A in these crops, respectively. Therefore, based on the results obtained in this work, use of the strain L. plantarum E3 could be an interesting option for the biopreservation of grapes

Antifungal activity of peracetic acid against toxigenic fungal contaminants of maize and barley at the postharvest stage

Contamination of maize and barley grain during storage by the toxigenic fungi Aspergillus flavus (A. flavus) and Penicillium Verrucosum (P. verrucosum) is both an economic and a public health problem, especially in less industrialized countries. Peracetic acid (PA) is a compound used for the disinfection of food and food contact surfaces. Unlike other disinfectants, it leaves no toxic residues and its decomposition products (CH3COOH, O2 nd H2O) are environmentally friendly. In order to apply PA to preserve maize and barley grain during storage, first, the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) against both fungi were determined in a 96-well sterile microplates. Then, the antifungal activity of the volatile PA was determined by depositing it on filter paper and Hydroxyethylcellulose (HEC) gels, which were placed in airtight 1L flasks together with PDA and maize and barley grain inoculated with both fungi. The MFC in liquid medium of A. flavus and P. verrucosum was 93.8 and 187.5 mg/L respectively. However, PA doses of 300 and 200 mg/L on HEC gels were required in order to observe significant antifungal and antimycotoxigenic activity in maize and barley grain inoculated with these fung

Bioaccessibility and decomposition of cylindrospermopsin in vegetablesmatrices after the application of anin vitrodigestion model

Research on the human exposure to Cylindrospermopsin (CYN) via consumption of contaminated food is of great interest for risk assessment purposes. The aim of this work is to evaluate for the first time the CYN bioaccessibility in contaminated vegetables (uncooked lettuce and spinach, and boiled spinach) after an in vitro digestion model, including the salivar, gastric and duodenal phases and, colonic fermentation under lactic acid bacteria. The results obtained showed that the digestion processes are able to diminish CYN levels, mainly in the colonic phase, especially in combination with the boiling treatment, decreasing CYN levels in a significant way. Moreover, the potential decomposition products in a pure CYN solution and in CYN-contaminated vegetables were evaluated using UHPLC-MS/MS Orbitrap. Under the conditions assayed, only two diastereoisomers of the same fragment with m/z 292.09617 have been detected in all the analysed samples, with the exception of digested vegetables. Therefore, in terms of risk assessment, the digestion seems to play an important role in reducing the final bioaccesibility of CYN, and the consumption of cooked vegetables (spinach) would be safer in comparison to raw vegetables.Ministerio de Economía y Competitividad (AGL2015-64558-R, MINECO/FEDER, UE