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This paper aims to contribute to the understanding of the knowledge that Beer's viable system model helps when applied to the study of change processes in organisations.

This paper develops a case study constructed on interviews and shared reflections by the author and a key player in the company. Aspects of the case study are then seen with an epistemological lens.

While it is apparent that ideas, purposes, values or policies depend on resources to happen, this paper argues that it is necessary their embodying in effective relations to succeed creating and producing desirable meanings.

Some forms of embodiment are more effective than others. The viable system model offers embodiment criteria to increase the chances of a successful production of ideas, purposes, values and policies, and the case study shows that for this purpose a limitation is transforming long‐established relationships.

This paper uses a particular and unique situation to illustrate through the viable system model some of the general difficulties that organisations face in achieving desirable transformations.

This study was conducted with the aim of examining the ability of Saccharomyces cerevisiae to remove AFB₁ from liquid media in order to use data in food and feed systems.

The binding of AFB₁ to Saccharomyces cerevisiae in the late exponential and early stationary phases was studied for viable, heat killed and acid killed yeast. AFB₁ at concentrations (5, 10 and 20 μg/l) was added to the yeast culture (10⁹ cfu/ml) in yeast mold broth medium and incubated at 25°C for 4, 12 and 24 hrs. The aflatoxin binding capacity of the strain was quantified by the amount of unbound AFB₁ using ELISA technique.

The detoxification rate for different treatments reported as follows: acid treated cells > heat treated cells > viable cells. Also, the most reduction in AFB₁ concentration happened within the first four hours of incubation with no significant increase in AFB₁ binding on further incubation because of saturation of active sites in yeast cells. According to the results, either form of Saccharomyces cerevisiae (viable or nonviable) is effective in aflatoxin binding from medium and the binding has a physical nature.

The findings reduce the public concern about aflatoxin B₁ contamination in foods and feeds having high risk of aflatoxin contamination.

No research had been done to assess the ability of Saccharomyces cerevisiae in the mentioned forms to detoxify AFB₁.

This paper aims to evaluate the cellular injuries associated with spray‐drying of Lactobacillus rhamnosus GG (LGG) in trehalose/monosodium glutamate (MSG) media by means of flow cytometry measurements; and also whether, and to what extent, the probiotic remain stable and viable in food formulations.

Spray‐drying was applied in the production of trehalose‐based preparations containing LGG. To gain more insights on the cellular damages that must have occurred during drying, flow cytometric analysis was applied in combination with carboxyfluorescein diacetate (cFDA) and PI stains. Spray‐dried samples were observed by scanning electron microscopy (SEM). The storage stability of spray‐dried LGG was monitored in food samples over a period of time.

It was observed that during spray‐drying, 1.80×10⁹ CFU/ml viable counts, which were equivalent of 68.8 per cent cells, were recovered in trehalose matrices but on incorporating 12.5 g/l MSG as a carrier component, survival rates were significantly improved. Density plot analysis showed a higher degree of membrane damage in cells spray‐dried in trehalose without MSG. SEM revealed no difference in the shapes and surfaces of spray‐dried samples. Evaluation of the recovery rates of LGG, initial count of ∼10⁹ CFU/ml or g, at storage time intervals revealed a minimum level of ∼10⁵ CFU/ml in apple juice after 12 days and ∼10⁷ CFU/g in chocolate beverages after ten weeks.

The potential contribution of MSG as a carrier component with trehalose in preventing higher losses during spray‐drying and food storage is pointed out in this study.

The main purpose of this research work is to study the effect of poly lactic acid (PLA) addition into poly (e-caprolactone) (PCL) matrices, as well the influence of the mixing process on the morphological, thermal, chemical, mechanical and biological performance of the 3D constructs produced with a novel biomanufacturing device (BioCell Printing).

Two mixing processes are used to prepare PCL/PLA blends, namely melt blending and solvent casting. PCL and PCL/PLA scaffolds are produced via BioCell Printing using a 300-μm nozzle, 0/90° lay down pattern and 350-μm pore size. Several techniques such as scanning electron microscopy (SEM), simultaneous thermal analyzer (STA), nuclear magnetic resonance (NMR), static compression analysis and Alamar BlueTM are used to evaluate scaffold's morphological, thermal, chemical, mechanical and biological properties.

Results show that the addition of PLA to PCL scaffolds strongly improves the biomechanical performance of the constructs. Additionally, polymer blends obtained by solvent casting present better mechanical and biological properties, compared to blends prepared by melt blending.

This paper undertakes a detailed study on the effect of the mixing process on the biomechanical properties of PCL/PLA scaffolds. Results will enable to prepare customized PCL/PLA scaffolds for tissue engineering applications with improved biological and mechanical properties, compared to PCL scaffolds alone. Additionally, the accuracy and reproducibility of by the BioCell Printing enables to modulate the micro/macro architecture of the scaffolds enhancing tissue regeneration.

The purpose of this paper is to propose a planning strategy for the radio frequency ablation (RFA) treatment of hepatic tumors. The goal is to give to the surgeon the opportunity of controlling the shape and the size of the treated volume and preserving the healthy tissues.

A FEM model of the human torso is built from radiographic and MRI scans of the patients, and then the RFA treatment “dynamically optimized” by controlling currents in multiple external electrodes, in such a way to drive currents in the desired regions, burning the tumor while trying to preserve healthy regions. A suitable cellular death model is considered in order to achieve an effective description of the biological modifications in the tumor volume.

A numerical method to plan the RFA treatment of hepatic tumors has been defined, aiming to preserve as much as possible healthy tissues.

The method depends on the knowledge of inner structure and properties of the patient's torso; while the structure of tissues can be determined by TAC or MRI scans, the physiological properties are much more uncertain.

The proposed approach allows optimized RFA treatments to be designed, allowing reduction of damage to healthy tissues deriving from application of the treatment.

The problem of optimal design of RFA treatments has been previously tackled in literature, but in this paper, dynamical optimization techniques and a cell death rate model have been included.

During the past 50 years the phenomenon of nuclear magnetic resonance (NMR) has evolved from a scientific curiosity to a powerful analytical tool for physical scientists and the medical community. Its primary use is for analytical chemistry and medical imaging. NMR imaging and spectroscopy can non‐invasively and non‐destructively examine the physical and chemical composition of materials. The technology is now at a level of sophistication and maturity where industrial applications are possible. This article describes the basis of NMR imaging and spectroscopy and examines the application of NMR to a broad range of industrial applications.

Consumer inclination towards probiotic foods has been stimulated due to well-documented evidence of health benefits of probiotic-containing products and consumer demand for natural products. It is assumed that the viability and metabolic activities of probiotics are essential for extending health benefits and for successful marketing of probiotics as a functional food. The purpose of this paper is to demonstrate that even dead or inactivated probiotic cells could extend health benefits, indicating that probiotic viability is not always necessary for exhibiting health benefits.

Attempt has been made to review the literature on the status of probiotic foods available in the world market, their impact on the gut flora and the various factors affecting their viability. Both review and research papers related to efficacy of inactivated, killed or dead probiotic cells towards health benefits have been considered. Keywords used for data search included efficacy of viable or killed, inactivated probiotic cells.

The reviewed literature indicated that inactivated, killed or dead probiotic cells also possess functional properties but live cells are more efficacious. All live probiotic cultures are not equally efficacious, and accordingly, dead or inactivated cells did not demonstrate functional properties to extend health benefits to all diseases.

Capability of non-viable microorganisms to confer health benefits may attract food manufacturers owing to certain advantages over live probiotics such as longer shelf-life, handling and transportation and reduced requirements for refrigerated storage and inclusion of non-bacterial, biologically active metabolites present in fermented milks’ fraction as dried powders to food matrixes may result in the development of new functional foods.

The authors aim to report a novel encapsulation technology for probiotic bacteria, through which L. casei CRL431 cells have been successfully delivered in shelf stable dry and intermediate moisture foods.

Manufacturing of the probiotic ingredient involved a proprietary technique using combination of controlled fermentation of the L. casei CRL431 cells, encapsulation in a food grade matrix and drying under controlled parameters.

The developed ingredient was stored at 25°C for a period of 12 months. The loss in cell viability was 1.9 log cfu g-1 after 12 months and maintained at 8.3 log cfu g-1. In vitro gastric juice and bile salts incubation revealed that the probiotic cells were better protected within the encapsulated than in the free form. The survival of the encapsulated cells was 5.0 and 2.1 log cycles higher than free cells in gastric juice and bile salt solution respectively. Fortification of probiotic bacteria did not have any negative impact on the sensory qualities of the foods mentioned above.

The developed technology is only applicable for fortifying dried or intermediate moisture foods with beneficial probiotic bacteria. The water activity of the products needs to be ranged from 0.2 to 0.5. A higher moisture contained food will lead to bacterial proliferations, product spoilage and loss in storage viability of the fortified probiotic cells.

A general guideline issued by FAO/WHO states that any good effect of probiotic bacteria on human health can be obtained only if consumed at a level of 10^7 to 10^8 viable cells per day. Delivery of such a concentration of live probiotic cells is particularly challenging in the case of long shelf life foods. As shown in the results, the authors' probiotic powder is able to deliver over 100 million live cells per gram after 12 months of ambient storage. Even the foods fortified with this powder are able to deliver over 1 million cells per gram after six months of ambient storage.

The developed technology rightly identified the gap for fortifying probiotic bacteria into foods stored under ambient conditions which is a real hindrance to reach out to consumers particularly in the developing countries where refrigerated supply chain and storage are not yet established in an efficient way. It is believed that millions of people in developing countries with a tropical climate would be benefited with the goodness of probiotic bacteria using the help of this technology.

The research work presented here is completely original and in-house research output of the Riddet Institute, Massey University, New Zealand. A successful commercialization of this new novel technology is deemed to be of very high value to any institution.

The purpose of this paper is to assess equipment surfaces associated with the production of Baker's compressed yeast for microbial biofilms.

Yeast and bacteria (aerobic plate counts – APC, Enterococcus, E. coli and coliforms) attached to five processing equipment surfaces in a yeast processing factory were enumerated after dislodging from stainless steel squares (“mock” surfaces), or swabbing, after 7, 14, 21 and 28 days of yeast of production. Attached populations were visualized by scanning electron microscopy (SEM).

A similar increasing trend in attached bacterial counts on all equipment surfaces was observed over 28 days using both “mock” surface and swabbing techniques. However, bacterial and viable yeast counts obtained using “mock” surfaces were significantly higher (P<0.05) by ca. 1 to 2.5 log CFU/cm² compared to corresponding counts obtained by swabbing. Overall E. coli and coliform counts were below the lower detection limit (0.7 log CFU/cm²), Enterococcus counts ranged from 2.30 log CFU/cm² to 4.69 CFU/cm², and APC ranged from 2.17 CFU/cm² to 4.89 CFU/cm². Highest attached bacterial counts were consistently recorded on the hopper and extruder. SEM of “mock” surfaces confirmed the accumulation of yeast cells and attachment of rod and coccoid‐shaped bacterial cells. Predominant surface‐associated bacterial populations were Enterococcaceae (70%), Lactobacillus (20%) and Gram‐negative rods (10%).

Biofilms on stainless steel yeast processing equipment surfaces may act as potential sources of during production spoilage contamination of Baker's compressed yeast.

Lactobacillus rhamnosus GG, a probiotic of human origin, known to have health beneficial effects can be exposed to osmotic stress when applied in food production as important quantities of sugars are added to the food product. The aim of this study is to assess the mode of action of non‐electrolytes stress on its viability.

Investigations were carried out on stationary phase cells treated with 0‐1.5M sugars, by means of flow cytometric method (FCM) and plate enumeration method. Osmotically induced changes of microbial carboxyfluorescein (cF)‐accumulation capacity and propidium iodide‐exclusion were monitored. The ability of the cells to extrude intracellularly accumulated cF upon glucose energization was ascertained as an additional vitality marker, in which the kinetics of dye extrusion were taken into consideration as well. Sugar analysis by HPLC was also carried out.

The results of FCM analysis revealed that with sucrose, only cells treated at 1.5M experienced membrane perturbation but there was a preservation of membrane integrity and enzymatic activity. There was no loss of viability as shown by plate counts. In contrast, the majority of trehalose‐treated cells had low extent of cF‐accumulation. For these samples a slight loss of viability was recorded on plating (logN/N_o ∼ −0.45). At 0.6M, cells had similar extrusion ability as the control cells upon glucose energization. However, 20 per cent of sucrose‐treated cells and 80 per cent of trehalose‐treated cells extruded the dye in the first 10min.

This finding pointed out the importance of trehalose to enhance the dye extrusion activity, which is regarded as an analogue of the capability of cells to extrude toxic compounds. Sugars exert different effects on the physiological and metabolic status of LGG but none caused a significant viability loss. LGG can be a choice probiotic bacterium in sugar‐rich food production e.g. candies, marmalade etc., in which exposure to high osmotic pressure is be expected.