Characterisation of the probiotic potential of Lactiplantibacillus plantarum K16 and its ability to produce the postbiotic metabolite γ-aminobutyric acid

Lactiplantibacillus plantarum has been widely studied due to its beneficial effects on health such as protect against pathogens, enhance the immune system, or produce metabolites like γ-aminobutyric acid (GABA). The objective of this study was the evaluation of the GABA-producer L. plantarum K16 isolated from kimchi. The safety and probiotic characterisation of this strain was performed by analysing carbohydrates fermentation, enzymatic activity, antibiotics susceptibility, and haemolytic and antimicrobial activity. Likewise, GABA production was optimised following a one-factor-at-a-time procedure by changing relevant fermentation parameters like incubation temperature, yeast extract concentration and fermentation time. The results indicated that L. plantarum K16 has the potential to stimulate the digestion and absorption of several nutrients and it could have an inhibitory effect against pathogenic bacteria. The best results for GABA production by this strain was around 1000 mg/L, using 12 g/L of yeast extract, 34 °C of incubation temperature and 96 h of fermentation time.This work was supported by the Basque government (grant ELKARTEK – KK-2019/00034)

Characterization of volatile compounds of cooked wild Iberian red deer meat extracted with solid phase microextraction and analysed by capillary gas chromatography - mass spectrometry

Wild Iberian red deer meat demand and interest are increasing and, therefore, an in-depth characterization of meat quality is needed to meet consumer demands. The objective of the present work was to assess, for the first time, the volatile profile of cooked wild sport-hunted Iberian red deer meat. Twenty-three loin samples from male red deer (Cervus elaphus hispanicus) were cooked and the volatile profile was analysed using solid phase microextraction, followed by capillary gas chromatography-mass spectrometry. Fifty-five volatile compounds were found. The major ones in number and relative abundance were aldehydes (84%), followed by alcohols (11%), hydrocarbons (2.4%), ketones (1.7%), furans (0.34%) and sulphur compounds (0.18%). Hexadecanal was the major compound and other long-chain compounds such as (E)-2-tetradecen-1-ol or 2-pentadecanone were also reported in considerable abundance. Several compounds related to grass-based diets were identified (2,3-octanedione, hexadecane or 1-pentadecanol). Odour impact ratio of volatile compounds was calculated and dimethyl trisulphide, (E,E)-2,4-decadienal, decanal and dodecanal were the most odorant compounds affecting the flavour of the cooked deer meat.Gobierno Vasco | Ref. IT944-16Ministerio de Economía y Competitividad | Ref. RTC-2016-5327-2Axencia Galega de Innovación | Ref. IN607A2019/01CYTED | Ref. 119RT056

Biosynthesis of gamma-aminobutyric acid by Lactiplantibacillus plantarum K16 as an alternative to revalue agri-food by-products

Probiotic metabolites, known as postbiotics, have received attention due to their wide variety of promoting health effects. One of the most exciting postbiotic is gamma-aminobutyric acid (GABA), widely produced by lactic acid bacteria, due to its benefits in health. In addition, the performance of the biosynthesis of GABA by Lactiplantibacillus plantarum could be modulated through the modification of fermentation parameters. Due to their high nutritional value, agri-food by-products could be considered a useful fermentation source for microorganisms. Therefore, these by-products were proposed as fermentation substrates to produce GABA in this study. Previously, several experiments in Man Rogosa Sharpe (MRS) broth were performed to identify the most critical parameters to produce GABA using the strain Lactiplantibacillus plantarum K16. The percentage of inoculum, the initial pH, and the concentration of nutrients, such as monosodium glutamate or glucose, significantly affected the biosynthetic pathway of GABA. The highest GABA yield was obtained with 500 mM of monosodium glutamate and 25 g/L of glucose, and an initial pH of 5.5 and 1.2% inoculum. Furthermore, these investigated parameters were used to evaluate the possibility of using tomato, green pepper, apple, or orange by-products to get GABA-enriched fermented media, which is an excellent way to revalorise them.This work was supported by the Basque government (grant ELKARTEK – KK-2019/00034)

Mountain sheep grazing systems provide multiple ecological, socio-economic, and food quality benefits

Altres ajuts: Basque Government to E.G (IT1022-16), A.A (IT1365-19), and L.J.R.B. (IT944-16)Unidad de excelencia María de Maeztu CEX2019-000940-MPastoral systems face increasing pressure from competing global markets, food sector industrialization, and new policies such as Europe's post-2020 Common Agriculture Policy. This pressure threatens the use of extensive sheep-grazing systems in mountain areas of low productivity but high natural value. Using information gathered at a long-term research setting in a mountainous area of the Basque Country (northern Spain), we assessed the multiple benefits of extensive dairy sheep grazing systems from multiple perspectives using indicators pertaining to ecological, socio-economic, and food quality domains. In this way, we address the benefits that would be lost if sheep grazing abandonment persists in mountain regions. Our results show that the benefits of extensive dairy sheep grazing in the research area include the production of healthy and high-quality foods and multiple ecological benefits including biodiversity conservation. Extensive dairy sheep grazing also contributes to rural development by generating employment and income in marginal, low-productivity lands that can support few economic alternatives. In particular, we found that sheep farmers who produce high-value products, such as cheese, have enhanced their economic profitability and are less dependent on public subsidies. However, careful attention to sustainable practices, support for new generations of farmers, and streamlined supply chains are required. These would contribute to ensure socio-economic benefits for farmers, avoid the ecological costs associated with grazing abandonment, and enhance ecosystem services for the whole society

Development of a Computational Software to Forecast Ozone Levels

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Identification of odour-active compounds in ewes' raw milk commercial cheeses with sensory defects

International audienceThe aim of this work was to identify key odorant compounds associated with main off-flavours (acid, rancid and faecal) and one defect related to the internal appearance (big irregular eyes) in ewes' raw milk commercial cheeses. Cheese samples were submitted to solvent assisted flavour evaporation (SAFE) and odorant compounds were detected by gas chromatography-olfactometry (GC-O). Odour-active compounds detected by GC-O were identified and quantified by gas chromatography-mass spectrometry (GC-MS). Partial least square regression was performed to determine relationships between relative abundances of the odour-active compounds and sensory defects of commercial cheeses. An imbalance in the concentration of short-chain free fatty acids, predominant compounds in all cheese samples, was associated with acid and rancid off-flavour, whereas faecal off-flavour was related to minor compounds such as 4-methylphenol and 3-methyl-1-butanol. No volatile compound could be related to the defect of big irregular eyes

Odour active compounds in raw sheep-milk cheeses with flavour defects

proceedings paper from the 14th Weurman Flavour Research Symposium (15-19 September 2014, Queens' College Cambridge, UK)absen

Identification of odour-active compounds in ewes' raw milk commercial cheeses with sensory defects

7th IDF International Symposium on Sheep, Goat and other Non-Cow MilkInternational audienceThe aim of this work was to identify key odorant compounds associated with main off-flavours (acid, rancid and faecal) and one defect related to the internal appearance (big irregular eyes) in ewes' raw milk commercial cheeses. Cheese samples were submitted to solvent assisted flavour evaporation (SAFE) and odorant compounds were detected by gas chromatography-olfactometry (GC-O). Odour-active compounds detected by GC-O were identified and quantified by gas chromatography-mass spectrometry (GC-MS). Partial least square regression was performed to determine relationships between relative abundances of the odour-active compounds and sensory defects of commercial cheeses. An imbalance in the concentration of short-chain free fatty acids, predominant compounds in all cheese samples, was associated with acid and rancid off-flavour, whereas faecal off-flavour was related to minor compounds such as 4-methylphenol and 3-methyl-1-butanol. No volatile compound could be related to the defect of big irregular eyes. (C) 2016 Elsevier Ltd. All rights reserved

Main odor active compounds in sheep’s raw milk cheeses with flavour defect

Main odor active compounds in sheep’s raw milk cheeses with flavour defect. 9.congrès international Goût nutrition sant

Effect of ageing time on the volatile compounds from cooked horse meat

Volatile compounds from cooked and aged (0, 7, 14, 21 days) Hispano-Bretón horse meat (loin) were analyzed by solid-phase microextraction coupled to gas chromatography–mass spectrometry. A total of 77 volatile compounds were found, from which aldehydes were the predominant family. Most of the identified compounds had their origin in the degradation of lipids, with a negligible contribution of Maillard derived products. Odour impact ratios were calculated and used as indicators of the contribution of each compound to the total aroma and aldehydes were, in general, the major contributors to cooked horse meat aroma. Results revealed that ageing affected 15 of the volatile compounds detected. From them, hexadecanal and 2- and 3-methylbutanal significantly increased during ageing, presumably affecting the cooked meat odour as these have considerable odorant impact. Under the present study conditions, periods longer than 14 days would be necessary for significant changes in the volatile profile of cooked horse meat.Department of Economic Development and Infrastructures of the Basque Government is acknowledged for the doctoral fellowship of L.R.B. Lactiker Research Group (Basque Government IT944-16) funded this work as well as the contract of L.M.Peer reviewe