1
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To CM, Mylle M, Rebry F, Bossier S, Van der Meeren P, Pel L. Using 1H and 23Na NMR relaxometry as a novel tool to monitor the moisture and salt distribution in commercial low-moisture part skim mozzarella. Int Dairy J 2023. [DOI: 10.1016/j.idairyj.2023.105667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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2
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Martin CS, Jubelin G, Darsonval M, Leroy S, Leneveu-Jenvrin C, Hmidene G, Omhover L, Stahl V, Guillier L, Briandet R, Desvaux M, Dubois-Brissonnet F. Genetic, physiological, and cellular heterogeneities of bacterial pathogens in food matrices: Consequences for food safety. Compr Rev Food Sci Food Saf 2022; 21:4294-4326. [PMID: 36018457 DOI: 10.1111/1541-4337.13020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 07/12/2022] [Accepted: 07/14/2022] [Indexed: 01/28/2023]
Abstract
In complex food systems, bacteria live in heterogeneous microstructures, and the population displays phenotypic heterogeneities at the single-cell level. This review provides an overview of spatiotemporal drivers of phenotypic heterogeneity of bacterial pathogens in food matrices at three levels. The first level is the genotypic heterogeneity due to the possibility for various strains of a given species to contaminate food, each of them having specific genetic features. Then, physiological heterogeneities are induced within the same strain, due to specific microenvironments and heterogeneous adaptative responses to the food microstructure. The third level of phenotypic heterogeneity is related to cellular heterogeneity of the same strain in a specific microenvironment. Finally, we consider how these phenotypic heterogeneities at the single-cell level could be implemented in mathematical models to predict bacterial behavior and help ensure microbiological food safety.
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Affiliation(s)
- Cédric Saint Martin
- MICALIS Institute, Université Paris-Saclay, INRAE, AgroParisTech, Jouy-en-Josas, France.,Université Clermont Auvergne, INRAE, UMR454 MEDIS, Clermont-Ferrand, France
| | - Grégory Jubelin
- Université Clermont Auvergne, INRAE, UMR454 MEDIS, Clermont-Ferrand, France
| | - Maud Darsonval
- MICALIS Institute, Université Paris-Saclay, INRAE, AgroParisTech, Jouy-en-Josas, France
| | - Sabine Leroy
- Université Clermont Auvergne, INRAE, UMR454 MEDIS, Clermont-Ferrand, France
| | - Charlène Leneveu-Jenvrin
- MICALIS Institute, Université Paris-Saclay, INRAE, AgroParisTech, Jouy-en-Josas, France.,Association pour le Développement de l'Industrie de la Viande (ADIV), Clermont-Ferrand, France
| | - Ghaya Hmidene
- Risk Assessment Department, ANSES, Maisons-Alfort, France
| | - Lysiane Omhover
- Aerial, Technical Institute of Agro-Industry, Illkirch, France
| | - Valérie Stahl
- Aerial, Technical Institute of Agro-Industry, Illkirch, France
| | | | - Romain Briandet
- MICALIS Institute, Université Paris-Saclay, INRAE, AgroParisTech, Jouy-en-Josas, France
| | - Mickaël Desvaux
- Université Clermont Auvergne, INRAE, UMR454 MEDIS, Clermont-Ferrand, France
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3
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Alehosseini A, Sharma P, Sheehan JJ. Application of a dairy-based model system for mathematical mapping of diffusion of salt within rennet induced micellar casein concentrate matrices. J FOOD ENG 2022. [DOI: 10.1016/j.jfoodeng.2022.111263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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4
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Effect of cheese composition and cheese-making conditions on salt and moisture transfer during brining. Int Dairy J 2022. [DOI: 10.1016/j.idairyj.2022.105325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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5
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Shkembi B, Huppertz T. Calcium Absorption from Food Products: Food Matrix Effects. Nutrients 2021; 14:nu14010180. [PMID: 35011055 PMCID: PMC8746734 DOI: 10.3390/nu14010180] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/23/2021] [Accepted: 12/28/2021] [Indexed: 12/14/2022] Open
Abstract
This article reviews physicochemical aspects of calcium absorption from foods. Notable differences are observed between different food products in relation to calcium absorption, which range from <10% to >50% of calcium in the foods. These differences can be related to the interactions of calcium with other food components in the food matrix, which are affected by various factors, including fermentation, and how these are affected by the conditions encountered in the gastrointestinal tract. Calcium absorption in the intestine requires calcium to be in an ionized form. The low pH in the stomach is critical for solubilization and ionization of calcium salts present in foods, although calcium oxalate complexes remain insoluble and thus poorly absorbable. In addition, the rate of gastric transit can strongly affect fractional absorption of calcium and a phased release of calcium into the intestine, resulting in higher absorption levels. Dairy products are the main natural sources of dietary calcium in many diets worldwide, which is attributable to their ability to provide high levels of absorbable calcium in a single serving. For calcium from other food products, lower levels of absorbable calcium can limit contributions to bodily calcium requirements.
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Affiliation(s)
- Blerina Shkembi
- Food Quality & Design Group, Wageningen University & Research, 6708 WG Wageningen, The Netherlands;
| | - Thom Huppertz
- Food Quality & Design Group, Wageningen University & Research, 6708 WG Wageningen, The Netherlands;
- FrieslandCampina, 3818 LE Amersfoort, The Netherlands
- Correspondence:
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6
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Quality evaluation of white brined cheese stored in cans as affected by the storage temperature and time. Int Dairy J 2021. [DOI: 10.1016/j.idairyj.2021.105105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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7
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Kern C, Stefan T, Sacharow J, Kügler P, Hinrichs J. Predictive modeling of the early stages of semi-solid food ripening: Spatio-temporal dynamics in semi-solid casein matrices. Int J Food Microbiol 2021; 349:109230. [PMID: 34023621 DOI: 10.1016/j.ijfoodmicro.2021.109230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 04/01/2021] [Accepted: 04/26/2021] [Indexed: 11/17/2022]
Abstract
A mechanistic, spatio-temporal model to predict early stage semi-solid food ripening, exemplary for semi-solid casein matrices, was created using software based on the finite element method (FEM). The model was refined and validated by experimental data obtained during 8 wk of ripening of a casein matrix that was inoculated by one single central injection of starter culture. The resulting spatio-temporal distributions of lactococci strains, lactose, lactic acid/lactate and pH allowed us to optimize a number of parameters of the predictive model. Using the optimized model, the agreement between simulation and experiment was found to be satisfactory, with the pH matching best. The predictive model unveiled that effective diffusion of substrate and metabolites were crucial for an eventual homogeneous distribution of the measured substances. Hence, while using the optimized parameters from the single injection model, an injection technology for starter culture to inoculate and ferment casein matrices homogeneously was developed by means of solving another optimization problem with respect to injection positions. The casein matrix inoculated by the proposed injection pattern (21 injections, distance = 19 mm) showed sufficient homogeneity (bacterial activity and pH distribution) after the early stages of ripening, demonstrating the potential of application of the injection technology for fermentation of casein-based foods e.g. cheese.
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Affiliation(s)
- Christian Kern
- Department of Soft Matter Science and Dairy Technology, University of Hohenheim, Garbenstrasse 25, 70599 Stuttgart, Germany.
| | - Thorsten Stefan
- Institute of Applied Mathematics and Statistics, University of Hohenheim, Westhof-Süd, 70599 Stuttgart, Germany; Computational Science Lab, University of Hohenheim, Steckfeldstraße 2, 70599 Stuttgart, Germany
| | - Julia Sacharow
- Department of Soft Matter Science and Dairy Technology, University of Hohenheim, Garbenstrasse 25, 70599 Stuttgart, Germany
| | - Philipp Kügler
- Institute of Applied Mathematics and Statistics, University of Hohenheim, Westhof-Süd, 70599 Stuttgart, Germany; Computational Science Lab, University of Hohenheim, Steckfeldstraße 2, 70599 Stuttgart, Germany
| | - Jörg Hinrichs
- Department of Soft Matter Science and Dairy Technology, University of Hohenheim, Garbenstrasse 25, 70599 Stuttgart, Germany
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8
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Moniente M, García‐Gonzalo D, Ontañón I, Pagán R, Botello‐Morte L. Histamine accumulation in dairy products: Microbial causes, techniques for the detection of histamine‐producing microbiota, and potential solutions. Compr Rev Food Sci Food Saf 2021; 20:1481-1523. [DOI: 10.1111/1541-4337.12704] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 12/01/2020] [Accepted: 12/04/2020] [Indexed: 12/19/2022]
Affiliation(s)
- Marta Moniente
- Departamento de Producción Animal y Ciencia de los Alimentos Facultad de Veterinaria, Instituto Agroalimentario de Aragón‐IA2 (Universidad de Zaragoza‐CITA) Zaragoza Spain
| | - Diego García‐Gonzalo
- Departamento de Producción Animal y Ciencia de los Alimentos Facultad de Veterinaria, Instituto Agroalimentario de Aragón‐IA2 (Universidad de Zaragoza‐CITA) Zaragoza Spain
| | - Ignacio Ontañón
- Laboratorio de Análisis del Aroma y Enología, Química Analítica Facultad de Ciencias, Instituto Agroalimentario de Aragón‐IA2 (Universidad de Zaragoza‐CITA) Zaragoza Spain
| | - Rafael Pagán
- Departamento de Producción Animal y Ciencia de los Alimentos Facultad de Veterinaria, Instituto Agroalimentario de Aragón‐IA2 (Universidad de Zaragoza‐CITA) Zaragoza Spain
| | - Laura Botello‐Morte
- Departamento de Producción Animal y Ciencia de los Alimentos Facultad de Veterinaria, Instituto Agroalimentario de Aragón‐IA2 (Universidad de Zaragoza‐CITA) Zaragoza Spain
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9
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Wu X, Zhang M, Sun Y, Bhandari B, Fan D. Effects of cryoprotectants on
Nostoc sphaeroides
superchilled at low temperature (−3.0°C) and their action mechanisms. J FOOD PROCESS ENG 2020. [DOI: 10.1111/jfpe.13488] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xiao‐Fei Wu
- State Key Laboratory of Food Science and Technology Jiangnan University Wuxi Jiangsu China
- Yechun Food Production and Distribution Co., Ltd. Yangzhou Jiangsu China
| | - Min Zhang
- State Key Laboratory of Food Science and Technology Jiangnan University Wuxi Jiangsu China
- International Joint Laboratory on Food Safety Jiangnan University Wuxi Jiangsu China
| | - Yanan Sun
- State Key Laboratory of Food Science and Technology Jiangnan University Wuxi Jiangsu China
- Jiangsu Province Key Laboratory of Advanced Food Manufacturing Equipment and Technology Jiangnan University Wuxi Jiangsu China
| | - Bhesh Bhandari
- School of Agriculture and Food Sciences University of Queensland Brisbane Queensland Australia
| | - Dongcui Fan
- State Key Laboratory of Food Science and Technology Jiangnan University Wuxi Jiangsu China
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10
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Sezer B, Bilge G, Eseller KE, Berberoglu H, Boyaci IH. Laser induced breakdown spectroscopy based diffusion modelling in cheese matrix. J FOOD ENG 2019. [DOI: 10.1016/j.jfoodeng.2019.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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11
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Chua JCL, Hale JDF, Silcock P, Bremer PJ. Bacterial survival and adhesion for formulating new oral probiotic foods. Crit Rev Food Sci Nutr 2019; 60:2926-2937. [PMID: 31556313 DOI: 10.1080/10408398.2019.1669528] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Probiotics are defined as live microorganisms, which, when administered in adequate amounts, confer health benefits to the host. Traditionally, probiotic food research has heavily focused on the genera Bifidobacteria and Lactobacilli, along with their benefits for gut health. Recently with the identification of new probiotic strains specifically intended for oral health applications, the development of probiotic foods for oral health benefits has garnered interest, with a renewed focus on identifying new food formats for delivering probiotics. The development of novel oral probiotic foods is highly complex, as the composition of a food matrix dictates: (1) bacterial viability during production and shelf life and (2) how bacteria partition with components within a food matrix and subsequently adhere to oral cavity surfaces. At present, virtually no information is available on oral probiotic strains such as Streptococcus salivarius; specifically, how orally-derived strains survive under different food parameters. Furthermore, limited information exists on the partition behavior of probiotics with food components, governed by physico-chemical interactions and adhesion phenomena. This review aspires to examine this framework by providing a foundation with existing literature related to the common probiotic genera, in order to inform and drive future attempts of designing new oral probiotic food formats.
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Affiliation(s)
- Jonathan C L Chua
- Department of Food Science, University of Otago, Dunedin 9054, New Zealand
| | | | - Pat Silcock
- Department of Food Science, University of Otago, Dunedin 9054, New Zealand
| | - Phil J Bremer
- Department of Food Science, University of Otago, Dunedin 9054, New Zealand
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12
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Paramita VD, Kasapis S. Molecular dynamics of the diffusion of natural bioactive compounds from high-solid biopolymer matrices for the design of functional foods. Food Hydrocoll 2019. [DOI: 10.1016/j.foodhyd.2018.09.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Hickey C, Fallico V, Wilkinson M, Sheehan J. Redefining the effect of salt on thermophilic starter cell viability, culturability and metabolic activity in cheese. Food Microbiol 2018; 69:219-231. [DOI: 10.1016/j.fm.2017.08.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 08/08/2017] [Accepted: 08/22/2017] [Indexed: 11/26/2022]
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14
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Blaya J, Barzideh Z, LaPointe G. Symposium review: Interaction of starter cultures and nonstarter lactic acid bacteria in the cheese environment. J Dairy Sci 2017; 101:3611-3629. [PMID: 29274982 DOI: 10.3168/jds.2017-13345] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Accepted: 10/24/2017] [Indexed: 12/21/2022]
Abstract
The microbiota of ripening cheese is dominated by lactic acid bacteria, which are either added as starters and adjunct cultures or originate from the production and processing environments (nonstarter or NSLAB). After curd formation and pressing, starters reach high numbers, but their viability then decreases due to lactose depletion, salt addition, and low pH and temperature. Starter autolysis releases cellular contents, including nutrients and enzymes, into the cheese matrix. During ripening, NSLAB may attain cell densities up to 8 log cfu per g after 3 to 9 mo. Depending on the species and strain, their metabolic activity may contribute to defects or inconsistency in cheese quality and to the development of typical cheese flavor. The availability of gene and genome sequences has enabled targeted detection of specific cheese microbes and their gene expression over the ripening period. Integrated systems biology is needed to combine the multiple perspectives of post-genomics technologies to elucidate the metabolic interactions among microorganisms. Future research should delve into the variation in cell physiology within the microbial populations, because spatial distribution within the cheese matrix will lead to microenvironments that could affect localized interactions of starters and NSLAB. Microbial community modeling can contribute to improving the efficiency and reduce the cost of food processes such as cheese ripening.
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Affiliation(s)
- J Blaya
- Department of Food Science, University of Guelph, Ontario, Canada N1G 2W1
| | - Z Barzideh
- Department of Food Science, University of Guelph, Ontario, Canada N1G 2W1
| | - G LaPointe
- Department of Food Science, University of Guelph, Ontario, Canada N1G 2W1.
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15
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Wemmenhove E, Wells-Bennik M, Stara A, van Hooijdonk A, Zwietering M. How NaCl and water content determine water activity during ripening of Gouda cheese, and the predicted effect on inhibition of Listeria monocytogenes. J Dairy Sci 2016; 99:5192-5201. [DOI: 10.3168/jds.2015-10523] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 02/14/2016] [Indexed: 11/19/2022]
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16
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Acerbi F, Guillard V, Guillaume C, Saubanere M, Gontard N. An appraisal of the impact of compositional and ripening parameters on CO2 diffusivity in semi-hard cheese. Food Chem 2016; 194:1172-9. [DOI: 10.1016/j.foodchem.2015.08.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 07/25/2015] [Accepted: 08/07/2015] [Indexed: 10/23/2022]
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17
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Chapeau A, Silva JV, Schuck P, Thierry A, Floury J. The influence of cheese composition and microstructure on the diffusion of macromolecules: A study using Fluorescence Recovery After Photobleaching (FRAP). Food Chem 2016; 192:660-7. [DOI: 10.1016/j.foodchem.2015.07.053] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 07/08/2015] [Accepted: 07/10/2015] [Indexed: 11/15/2022]
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18
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Jeanson S, Floury J, Gagnaire V, Lortal S, Thierry A. Bacterial Colonies in Solid Media and Foods: A Review on Their Growth and Interactions with the Micro-Environment. Front Microbiol 2015; 6:1284. [PMID: 26648910 PMCID: PMC4664638 DOI: 10.3389/fmicb.2015.01284] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 10/31/2015] [Indexed: 01/26/2023] Open
Abstract
Bacteria, either indigenous or added, are immobilized in solid foods where they grow as colonies. Since the 80's, relatively few research groups have explored the implications of bacteria growing as colonies and mostly focused on pathogens in large colonies on agar/gelatine media. It is only recently that high resolution imaging techniques and biophysical characterization techniques increased the understanding of the growth of bacterial colonies, for different sizes of colonies, at the microscopic level and even down to the molecular level. This review covers the studies on bacterial colony growth in agar or gelatine media mimicking the food environment and in model cheese. The following conclusions have been brought to light. Firstly, under unfavorable conditions, mimicking food conditions, the immobilization of bacteria always constrains their growth in comparison with planktonic growth and increases the sensibility of bacteria to environmental stresses. Secondly, the spatial distribution describes both the distance between colonies and the size of the colonies as a function of the initial level of population. By studying the literature, we concluded that there systematically exists a threshold that distinguishes micro-colonies (radius < 100-200 μm) from macro-colonies (radius >200 μm). Micro-colonies growth resembles planktonic growth and no pH microgradients could be observed. Macro-colonies growth is slower than planktonic growth and pH microgradients could be observed in and around them due to diffusion limitations which occur around, but also inside the macro-colonies. Diffusion limitations of milk proteins have been demonstrated in a model cheese around and in the bacterial colonies. In conclusion, the impact of immobilization is predominant for macro-colonies in comparison with micro-colonies. However, the interaction between the colonies and the food matrix itself remains to be further investigated at the microscopic scale.
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Affiliation(s)
- Sophie Jeanson
- INRA, UMR1253, Science and Technology of Milk and EggsRennes, France
- AGROCAMPUS OUEST, UMR1253, Science and Technology of Milk and EggsRennes, France
| | - Juliane Floury
- INRA, UMR1253, Science and Technology of Milk and EggsRennes, France
- AGROCAMPUS OUEST, UMR1253, Science and Technology of Milk and EggsRennes, France
| | - Valérie Gagnaire
- INRA, UMR1253, Science and Technology of Milk and EggsRennes, France
- AGROCAMPUS OUEST, UMR1253, Science and Technology of Milk and EggsRennes, France
| | - Sylvie Lortal
- INRA, UMR1253, Science and Technology of Milk and EggsRennes, France
- AGROCAMPUS OUEST, UMR1253, Science and Technology of Milk and EggsRennes, France
| | - Anne Thierry
- INRA, UMR1253, Science and Technology of Milk and EggsRennes, France
- AGROCAMPUS OUEST, UMR1253, Science and Technology of Milk and EggsRennes, France
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19
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Silva JV, Lortal S, Floury J. Diffusion behavior of dextrans in dairy systems of different microstructures. Food Res Int 2015. [DOI: 10.1016/j.foodres.2015.02.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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20
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Hickey CD, Sheehan JJ, Wilkinson MG, Auty MAE. Growth and location of bacterial colonies within dairy foods using microscopy techniques: a review. Front Microbiol 2015; 6:99. [PMID: 25741328 PMCID: PMC4332360 DOI: 10.3389/fmicb.2015.00099] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 01/26/2015] [Indexed: 11/13/2022] Open
Abstract
The growth, location, and distribution of bacterial colonies in dairy products are important factors for the ripening and flavor development of cheeses, yogurts, and soured creams. Starter, non-starter, spoilage, and pathogenic bacteria all become entrapped in the developing casein matrix of dairy foods. In order to visualize these bacterial colonies and the environments surrounding them, microscopy techniques are used. The use of various microscopy methods allow for the rapid detection, enumeration, and distribution of starter, non-starter and pathogenic bacteria in dairy foods. Confocal laser scanning microscopy is extensively utilized to identify bacteria location via the use of fluorescent dyes. Further study is needed in relation to the development of micro- gradients and localized ripening parameters in dairy products due to the location of bacteria at the protein-fat interface. Development in the area of bacterial discrimination using microscopy techniques and fluorescent dyes/tags is needed as the benefits of rapidly identifying spoilage/pathogenic bacteria early in product manufacture would be of huge benefit in relation to both safety and financial concerns.
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Affiliation(s)
- Cian D. Hickey
- Teagasc Food Research CentreFermoy, Ireland
- University of LimerickLimerick, Ireland
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21
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Abstract
The effect of different brining treatments on salt uptake and diffusion during the first 30 d of ripening was determined in soft ewe cheese. Additionally, salt influence on surface microorganisms and physicochemical parameters was evaluated. Cheeses were placed into different brine solutions (14, 18 and 24°Bé) at 5 and 10 °C for 1, 2 or 3 h. Samples from rind, outer core and inner core were analysed at 0, 7, 15 and 30 d. Complete salt diffusion from rind to the inner core took about 15 d. The resulting salt gradient favoured the development of a pH gradient from the surface to the inner core. Salt concentration also had a significant effect on the growth of surface microorganisms (mesophiles, pseudomonads and halotolerants). However, mould and yeasts were not affected throughout ripening by the salt levels achieved. Brine salting by immersion for 3 h at 10 °C in 24°B brine was found to be the most suitable treatment to control pseudomonads in cheese rind, as spoilage microorganism.
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22
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Stulova I, Kabanova N, Kriščiunaite T, Adamberg K, Laht TM, Vilu R. Microcalorimetric study of the growth of Streptococcus thermophilus in renneted milk. Front Microbiol 2015; 6:79. [PMID: 25713570 PMCID: PMC4322847 DOI: 10.3389/fmicb.2015.00079] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 01/22/2015] [Indexed: 11/13/2022] Open
Abstract
The growth of Streptococcus thermophilus ST12 (ST12) in liquid milk, reconstituted from low-heat skim milk powder reconstituted skim milk (RSM) and in RSM with rennet addition (r-RSM) at 40°C was monitored by microcalorimetry. It was shown that the growth rate of bacteria decreased in renneted samples in comparison with liquid RSM starting from certain sizes of the colonies ("deviation moments"), which depended on the inoculation rates. The hydrolysis of lactose was delayed for about 1 h in the r-RSM in comparison with RSM but otherwise the metabolism of carbohydrates in the renneted and non-renneted milks was similar. The total free amino acids (TFAA) content by the end of fermentations was higher in r-RSM than in RSM presumably due to the enzymatic hydrolytic activity of rennet. The quantitatively dominating amino acids were remarkably different in the r-RSM and RSM indicating that the hydrolysis cascade of caseins and/or metabolism of amino acids by the bacteria functioned differently in the two cases. The data obtained showed potential of microcalorimetry to characterize quantitative differences of growth and metabolism of the bacteria in renneted and liquid samples of milk.
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Affiliation(s)
- Irina Stulova
- Department of Chemistry, Tallinn University of Technology Tallinn, Estonia ; Competence Centre of Food and Fermentation Technologies Tallinn, Estonia
| | - Natalja Kabanova
- Competence Centre of Food and Fermentation Technologies Tallinn, Estonia
| | - Tiina Kriščiunaite
- Competence Centre of Food and Fermentation Technologies Tallinn, Estonia
| | - Kaarel Adamberg
- Department of Chemistry, Tallinn University of Technology Tallinn, Estonia ; Competence Centre of Food and Fermentation Technologies Tallinn, Estonia
| | - Tiiu-Maie Laht
- Department of Chemistry, Tallinn University of Technology Tallinn, Estonia
| | - Raivo Vilu
- Department of Chemistry, Tallinn University of Technology Tallinn, Estonia ; Competence Centre of Food and Fermentation Technologies Tallinn, Estonia
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23
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Hickey C, Auty M, Wilkinson M, Sheehan J. The influence of cheese manufacture parameters on cheese microstructure, microbial localisation and their interactions during ripening: A review. Trends Food Sci Technol 2015. [DOI: 10.1016/j.tifs.2014.10.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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24
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Van Wey A, Cookson A, Roy N, McNabb W, Soboleva T, Wieliczko R, Shorten P. A mathematical model of the effect of pH and food matrix composition on fluid transport into foods: An application in gastric digestion and cheese brining. Food Res Int 2014. [DOI: 10.1016/j.foodres.2014.01.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Giroux HJ, Bouchard C, Britten M. Combined effect of renneting pH, cooking temperature, and dry salting on the contraction kinetics of rennet-induced milk gels. Int Dairy J 2014. [DOI: 10.1016/j.idairyj.2013.10.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Guinee T, O’Callaghan D. Effect of increasing the protein-to-fat ratio and reducing fat content on the chemical and physical properties of processed cheese product. J Dairy Sci 2013; 96:6830-6839. [DOI: 10.3168/jds.2013-6685] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 06/29/2013] [Indexed: 11/19/2022]
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27
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Heilig A, Hahn C, Erpenbach K, Kübler K, Hinrichs J. Determination of Aroma Volatile Diffusion Coefficients in Set-Type Acidified Dairy Matrices of Different Composition and Microstructure by Means of the Concentration Profile Technique in Combination with Headspace Gas Chromatography. J Texture Stud 2013. [DOI: 10.1111/jtxs.12032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andrej Heilig
- Dairy Science and Technology; University of Hohenheim; Stuttgart 70593 Germany
| | - Christian Hahn
- Dairy Science and Technology; University of Hohenheim; Stuttgart 70593 Germany
| | | | - Katya Kübler
- Sachsenmilch Leppersdorf GmbH; Leppersdorf Germany
| | - Jörg Hinrichs
- Dairy Science and Technology; University of Hohenheim; Stuttgart 70593 Germany
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28
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Silva J, Peixoto P, Lortal S, Floury J. Transport phenomena in a model cheese: The influence of the charge and shape of solutes on diffusion. J Dairy Sci 2013; 96:6186-98. [DOI: 10.3168/jds.2013-6552] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 07/03/2013] [Indexed: 11/19/2022]
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29
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30
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Microgradients of pH do not occur around Lactococcus colonies in a model cheese. Appl Environ Microbiol 2013; 79:6516-8. [PMID: 23934499 DOI: 10.1128/aem.01678-13] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lactococci inoculated into cheese grow as colonies producing lactic acid. The pH microgradients were investigated around colonies in a complex food such as cheese. The results, obtained using a nondestructive technique, demonstrated that pH microgradients did not occur regardless of the acidification kinetics and the size of the colony.
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31
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Porosity of Lactococcus lactis subsp. lactis LD61 colonies immobilised in model cheese. Int J Food Microbiol 2013; 163:64-70. [PMID: 23558188 DOI: 10.1016/j.ijfoodmicro.2013.02.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 02/19/2013] [Accepted: 02/23/2013] [Indexed: 11/23/2022]
Abstract
During cheese ripening, micro-organisms grow as immobilised colonies, metabolising substrates present in the matrix which generate products triggered by enzymatic reactions. Local limitation rates of diffusion, either in the matrix or within the bacterial colonies, can be responsible for modulation in the metabolic and enzymatic activities of micro-organisms during ripening. How bacterial colonies immobilised in cheese are porous to these diffusing solutes has never been explored. The objective of this study was to determine if fluorescent dextrans of different sizes (4.4, 70 and 155 kDa) are able to penetrate through colonies of Lactococcus lactis LD61 immobilised in solid media, either agar or model cheese. Confocal microscopic observations showed that lactococcus colonies immobilised in these two media were porous to dextrans from 4 kDa to 155 kDa. However, the rate of diffusion of the solutes was faster inside the colonies immobilised in ultrafiltered-cheese than in agar when large dextrans were considered (≥70 kDa). The colonial shape of the lactococcus strain was also shown to be lenticular in agar and spherical in the model cheese, indicating that the physical pressure exerted on the colony by the surrounding casein network was probably isotropous in the UF-cheese but not in agar. In both cases, the fact that lactococcus colonies immobilised in solid media are porous to large dextran solutes suggests that substrates or enzymes are likely also to be able to migrate inside the colonies during cheese ripening.
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32
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Luo J, Pan T, Guo HY, Ren FZ. Effect of calcium in brine on salt diffusion and water distribution of Mozzarella cheese during brining. J Dairy Sci 2012. [PMID: 23200478 DOI: 10.3168/jds.2012-5888] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A soft, pasty, high-moisture surface defect occurs with progressive brining of Mozzarella cheese. Addition of calcium is traditionally used to prevent this defect but the underlying mechanism is not clear. Mozzarella cheese was formed into a cylinder inside brine on its plane surface to ensure semi-infinite, unidirectional mass transfer and placed into brine containing 0, 0.1, or 0.25% (wt/wt) calcium chloride. To monitor the effect on cheese composition of calcium in brine, we measured calcium and water contents of the cheese during brining. The extent of calcium loss from the cheese decreased significantly with the addition of calcium. Addition of calcium to a final concentration of 0.25% decreased the loss of calcium from 94.13 to 18.22% from the outside region of the cheese after 30 d, and the water content of the cheese was decreased from 67.8 to 48.8%. To further elucidate the effect of calcium in brine, the Boltzmann method was used to determine the effective diffusion coefficient value, and low-field nuclear magnetic resonance was used to measure the cheese transversal relaxation time. The migration of calcium interfered with salt diffusion. At the end of brining, the amount of water bound to the protein of the cheese significantly increased. Addition of calcium to a final concentration of 0.25% diminished the proportion of bound water by 20.96%. In conclusion, addition of calcium hinders the diffusion of sodium and modifies the distribution of water in Mozzarella cheese during brining.
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Affiliation(s)
- J Luo
- Key Laboratory of Functional Dairy, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
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Floury J, Madec MN, Waharte F, Jeanson S, Lortal S. First assessment of diffusion coefficients in model cheese by fluorescence recovery after photobleaching (FRAP). Food Chem 2012; 133:551-6. [DOI: 10.1016/j.foodchem.2012.01.030] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 10/13/2011] [Accepted: 01/13/2012] [Indexed: 11/26/2022]
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34
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Aly S, Floury J, Famelart MH, Madec MN, Dupont D, Le Gouar Y, Lortal S, Jeanson S. Nisin quantification by ELISA allows the modeling of its apparent diffusion coefficient in model cheeses. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:9484-9490. [PMID: 21770386 DOI: 10.1021/jf2008474] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The diffusion of small solutes in cheese is of key importance for most enzymatic reactions involved in the ripening process. However, only a limited amount of data is available on salt diffusion and practically none on peptide diffusion. Nisin, a bacteriocin peptide, migrated in model cheeses made from ultrafiltered (UF) retentate. A profile concentration device and an enzyme-linked immunosorbent assay (ELISA), specifically developed for nisin quantification in cheese, were used to model the apparent diffusion coefficients for nisin according to Fick's law. This average coefficient was 49.5 μm(2)/s in UF cheese (n = 2). When 10% gelatin was added to the retentate, this value decreased to 34.4 μm(2)/s (n = 2). The two cheeses differed in their macrostructure (rheology) and microstructure (confocal microscopy). This study provides the first apparent diffusion coefficients for a peptide in cheese and supports the hypothesis that composition and structure influence the diffusion of small solutes such as peptides.
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Affiliation(s)
- Samar Aly
- INRA, UMR1253, Science and Technology of Milk and Eggs, F-35000 Rennes, France
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35
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Jeanson S, Chadœuf J, Madec MN, Aly S, Floury J, Brocklehurst TF, Lortal S. Spatial distribution of bacterial colonies in a model cheese. Appl Environ Microbiol 2011; 77:1493-500. [PMID: 21169438 PMCID: PMC3067236 DOI: 10.1128/aem.02233-10] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Accepted: 12/08/2010] [Indexed: 11/20/2022] Open
Abstract
In most ripened cheeses, bacteria are responsible for the ripening process. Immobilized in the cheese matrix, they grow as colonies. Therefore, their distribution as well as the distance between them are of major importance for ripening steps since metabolites diffuse within the cheese matrix. No data are available to date about the spatial distribution of bacterial colonies in cheese. This is the first study to model the distribution of bacterial colonies in a food-type matrix using nondestructive techniques. We compared (i) the mean theoretical three-dimensional (3D) distances between colonies calculated on the basis of inoculation levels and considering colony distribution to be random and (ii) experimental measurements using confocal microscopy photographs of fluorescent colonies of a Lactococcus lactis strain producing green fluorescent protein (GFP) inoculated, at different levels, into a model cheese made by ultrafiltration (UF). Enumerations showed that the final numbers of cells were identical whatever the inoculation level (10(4) to 10(7) CFU/g). Bacterial colonies were shown to be randomly distributed, fitting Poisson's model. The initial inoculation level strongly influenced the mean distances between colonies (from 25 μm to 250 μm) and also their mean diameters. The lower the inoculation level, the larger the colonies were and the further away from each other. Multiplying the inoculation level by 50 multiplied the interfacial area of exchange with the cheese matrix by 7 for the same cell biomass. We finally suggested that final cell numbers should be discussed together with inoculation levels to take into account the distribution and, consequently, the interfacial area of colonies, which can have a significant influence on the cheese-ripening process on a microscopic scale.
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Affiliation(s)
- S Jeanson
- INRA, UMR1253, F-35000 Rennes, France.
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