70 research outputs found
Pengaruh Penambahan Pati Umbi Bengkuang (Pachyrhizus erosus) terhadap Kualitas Yoghurt Set Ditinjau dari pH, Total Asam, TPC dan Daya Ikat Air
No full textYoghurt set merupakan salah satu produk olahan berbahan dasar susu yang dihasilkan melalui fermentasi Bakteri Asam Laktat (BAL) yang proses inkubasinya ditempatkan dalam wadah tertentu, pada umumnya berwarna putih, memiliki rasa yang sangat asam serta tekstur yang sangat kental.
Tujuan penelitian ini adalah untuk mengetahui perbedaan pengaruh penambahan pati umbi bengkuang (Pachyrhizus erosus) terhadap kualitas yoghurt set ditinjau dari pH, total asam, TPC dan daya ikat air. Hasil yang didapatkan dari penelitian ini diharapkan dapat dijadikan sebagai sumber informasi tentang penggunaan pati umbi bengkuang (Pachyrhizus erosus) sebagai bahan tambahan dalam pembuatan yoghurt set yang diduga dapat meningkatkan kualitas ditinjau dari pH, total asam, TPC dan daya ikat air. Selain itu penelitian ini diharapkan mampu memberikan ilmu pengetahuan dan wawasan tentang teknologi dalam pengolahan yoghurt set.
Penelitian ini dilaksanakan pada tanggal 14 Desember 2018 sampai 14 Februari 2019 di Laboratorium Teknologi
Hasil Ternak Fakultas Peternakan Universitas Brawijaya, Laboratorium Pengujian Mutu dan Keamanan Pangan Fakultas Teknologi Pertanian Universitas Brawijaya serta Laboratorium Ilmu dan Teknologi Pangan Fakultas Teknologi Pertanian Universitas Muhamadiyah, Malang. Materi yang digunakan dalam penelitian ini adalah yoghurt set yang dibuat dari susu segar, pati umbi bengkuang (Pachyrhizus erosus) dan starter yoghurt (Lactobacillus bulgaricus, Streptococcus thermophillus dan Lactobacillus acidophillus). Metode yang digunakan dalam penelitian ini adalah metode percobaan dengan menggunakan Rancangan Acak Lengkap (RAL) dengan 4 perlakuan dan 4 ulangan. Adapun Perlakuan tersebut yaitu tanpa penambahan pati umbi bengkuang 0% (P0); 2% (P1); 4% (P2); dan 6% (P3) dari volume susu. Data yang diperoleh dianalisa dengan sidik ragam ANOVA dan apabila terdapat perbedaan dilanjutkan dengan Uji Jarak Berganda Duncan (UJBD).
Hasil penelitian menunjukkan bahwa penambahan pati umbi bengkuang sebagai stabilizer dengan berbagai konsentrasi menunjukkan perbedaan yang nyata (P0,05) terhadap TPC serta memberikan perbedaan yang sangat nyata (P<0,01) terhadap daya ikat air yoghurt set. Rataan nilai pH berkisar antara 3,80±0,09-3,65±0,02, rataan nilai total asam 0,87±0,10%-1,04±0,06%, rataan nilai TPC 7,42±0,04-7,89±0,05 log CFU/ml dan nilai rataan daya ikat air sebesar 53,58±1,60%-71,98±2,82 %.
Berdasarkan hasil penelitian maka dapat disimpulkan bahwa penambahan pati umbi bengkuang dapat meningkatkan kualitas yoghurt set. Penambahan pati pada konsentrasi 6% dapat memperbaiki tekstur yoghurt set dengan meningkatkan total asam, TPC dan daya ikat air serta dapat menurukan nilai pH. Perlakuan terbaik dihasilkan pada konsentrasi penambahan pati umbi bengkuang sejumlah 6% dengan nilai
total asam sejumlah 1,04%, TPC 7,89 log CFU/ml dan daya ikat air 71,98%, sedangkan nilai pH diperoleh dari P0 yaitu 3,80 tanpa penambahan pati umbi bengkuang. Saran dari penelitian ini adalah perlu dilakukan pengkajian lebih lanjut mengenai daya simpan dan lama pemeraman dari yoghurt set dengan penambahan pati umbi bengkuang
Fair and Sparse Solutions in Network-Decentralized Flow Control
No full textWe proposed network-decentralized control strategies, in which each actuator can exclusively rely on local information, without knowing the network topology and the external input, ensuring that the flow asymptotically converges to the optimal one with respect to the p -norm. For 1 < p < ∞ , the flow converges to a unique constant optimal up∗. We show that the state converges to the optimal Lagrange multiplier of the optimization problem. Then, we consider networks where the flows are affected by unknown spontaneous dynamics and the buffers need to be driven exactly to a desired set-point. We propose a network-decentralized proportional-integral controller that achieves this goal along with asymptotic flow optimality; now it is the integral variable that converges to the optimal Lagrange multiplier. The extreme cases p=1 and p=∞ are of some interest since the former encourages sparsity of the solution while the latter promotes fairness. Unfortunately, for p=1 or p=∞ these strategies become discontinuous and lead to chattering of the flow, hence no optimality is achieved. We then show how to approximately achieve the goal as the limit for p 1 or p ∞.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Team Tamas Keviczk
Quality Yoghurt Set with the Addition Lactobacillus acidophilus FNCC 0051 and Streptococcus thermophilus FNCC 0040 Encapsulated in Terms of pH, Total Titrated Acid, Syneresis, and Total Lactic Acid Bacteria
No full textProbiotics are generally added in the manufacture of food products because of their function that can provide benefits to human health, especially in the digestive tract. The probiotics used in this study were Lactobacillus acidophilus FNCC 0051 and Streptococcus thermophilus FNCC 0040 which were encapsulated and added in making yoghurt sets. The purpose of this study was to examine the physicochemical and microbiological quality of the yoghurt set with the addition of encapsulated Lactic Acid Bacteria (LAB). The research method used is a laboratory experiment using a completely randomized design (CRD) pattern with 4 treatments and 3 replications. The treatments given were P0 Addition of LAB without encapsulation (control) (2%); T1 addition of 2% encapsulated LAB (v/v); T2 added 3% encapsulated LAB (v/v) and T3 added 4% (v/v) encapsulated LAB. Data analysis used Analysis of Variance (ANOVA). The results of the analysis showed that the encapsulation using gelatin and Na alginate coatings gave a very significant difference (P<0.01) to the syneresis of yoghurt sets with the resulting average T0 (24.51±0.70%), T1 (23.52±0.76%), T2 (20.44±0.44%), and T3 (19.96±0.83), a significant difference (P<0.05) on the pH of the yoghurt set with the resulting average T0 (4.56±0.03), T1 (4.55±0.02), T2 (4.45±0.09), and T3 (4.40±0.07), a significant difference (P<0.05) to the total acid titrated yoghurt set with the resulting average, namely P0 (0.68±0.14%), T1 (1.05±0.03%), T2 (1.13±0.32%), T3 (1.31±0.21%), the significant difference (P<0.05) on the total LAB yoghurt set with the resulting average T0 (8.62±0.30 log CFU/ml), T1 (9.20±0.70 log CFU/ml), T2 (9.36±0.33 log CFU/ml), and T3 (9.51±0.10 log CFU/ml). It was concluded that the addition of the percentage of encapsulated LAB of 4% was able to improve the quality of the yoghurt set optimally.Keywords: yoghurt set, probiotics, encapsulation, pH, total acid, syneresis, total LA
Microencapsulated Lactobacillus acidophilus FNCC 0051 and Streptococcus thermophilus FNCC 0040 Technique Emulsion Using Gelatin and Sodium Alginate
No full textThe research was held from September 2021 until January 2022 in Laboratory Livestock Product Technology Universitas Brawijaya, Malang, Indonesia. Microencapsulation is a technique used to protect bacteria from harmful (extreme) environmental factors such as heating, freezing and low pH through a coating process or coating a core substance in this case LAB with a polymer wall layer. The purpose of this study was to obtain a combination of the use of gelatin and sodium alginate as a coating material in the encapsulation of Lactobacillus acidophilus FNCC 0051 and Streptococcus thermophilus FNCC 0040 using the emulsion technique based on its physical and microbiological properties. The research method used is a laboratory experiment using a completely randomized design (CRD) pattern with 3 treatments and 3 replications. The treatment using a combination of gelatin and sodium alginate consisted of T1 (1:1); T2 (1:2); T3 (1:3). Data were processed by Analysis of Variance (ANOVA); If the analysis happens to show a significant difference (P<0.05) or a very highly significant difference (P<0.01), then the Duncan's Multiple Range Test was applied. Data from the results of microstructure testing using Scanning Electron Microscopy which were qualitative were analyzed descriptively. The results of the analysis show that encapsulation using a combination of gelatin and sodium alginate gives a very significant difference (P<0.01) to the value of encapsulation efficiency and does not give a significant difference (P>0.05) on microcapsule particle size and microcapsule particle size distribution, with percentages T1 97.43±0.31%, T2 98.50±0.48%, T3 99.00±0.44 %; T1 1.08±0.07 µm; T2 1.18±0.11 µm; T3 0.95±0.11µm; and T1 4.79±1.04; T2 2.53±2.16; T3 4.15±3.13 and microcapsules using SEM showed the microcapsules were round and smooth. The combination of gelatin and sodium alginate T3 (1:3) as a microcapsule material is a good alternative to protect lactic acid bacteria so that it can be applied in food products functional
Topology-Independent Robust Stability Conditions for Uncertain MIMO Networks
No full textWe give a sufficient and a necessary condition for the topology-independent robust stability of networked systems formed by uncertain MIMO systems. Both conditions involve constants associated with the nominal node dynamics and arc interconnection matrices, the uncertainty bounds, and the maximum connectivity degree of the network; they are scalable (they can be checked locally), independent of the network topology and even of the number of nodes and arcs, and hold for networks of heterogeneous MIMO systems and interconnection matrices, with heterogeneous uncertainties. The dual cases of 1-norm and ∞-norm bounds are considered. In both cases, if the systems at the nodes are diagonal, we get a necessary and sufficient condition. We apply our results to the topology-independent robust stability analysis of a case-study from cancer biology.Accepted Author ManuscriptTeam Tamas Keviczk
Optimal duration and planning of switching treatments taking drug toxicity into account: a convex optimisation approach
No full textWe consider a multi-compartment evolutionary model representing growth, mutation and migration of cancer cells, as well as the effect of drugs, and we design optimal switching targeted cancer therapies where a single drug, or suitable drug combination, is given at each time so as to minimise not only the overall tumor size over a finite horizon, but also drug-provoked side effects. The strong diagonally- dominant structure of the model allows to solve the problem via convex optimisation. We provide an algorithm that yields optimality throughout the whole treatment duration by solving the convex optimisation problem with different horizons, and show how dwell time can be enforced via heuristics. Also the optimal treatment duration can be computed via convex optimisation. The proposed approaches are applied to a model of ALK-rearranged lung carcinoma.Accepted Author ManuscriptTeam Tamas Keviczk
Behaviour and Stability of Interconnected Systems: From Biological Applications to Opinion Dynamics
No full textAn interconnected system is composed of multiple well-defined self-contained subsystems that interact among them and that together create collective behaviours. We can find many examples of interconnected systems in real life. Ranging from biological systems, such as the growth and interaction of populations in diverse and spatially distributed environments, to electric grids connecting power-generating sources, buildings and infrastructures in a country. When studying interconnected systems, a fundamental and natural question is how the properties and characteristics of the individual subsystems and the way they are connected relate to the collective behaviour of the complete system. That is the driving question of the present dissertation. Given that interconnected systems can be found in a wide variety of contexts, their representation and specific research interests can be equally varied. Because of this, it is impossible to answer the aforementioned question uniquely for all interconnected systems, and specific cases must be considered. In this dissertation, we consider two types of interconnected systems: a general class of uncertain multiple-input-multipleoutput (MIMO) systems, and agent-based opinion formation models. The investigation of uncertain MIMO interconnected systems is focused on providing topology-independent conditions for robust stability. The primary motivation for this approach is that, in real systems, it is costly or even impossible to have complete and accurate information on the network topology and subsystem parameters and dynamics. However, it is of critical interest to guarantee the system’s stability. Therefore we need stability conditions that require only partial information about the network and the subsystems to ensure the system’s stability. By studying these systems both in the time and frequency domain, we are able to provide conditions thatmeet these requirements. As for agent-based opinion formation models, we assume that each individual (or agent) in a population has an opinion about a statement. By exchanging opinions among themselves, the agents update their own internal opinion, resulting in a collective dynamic of opinion evolution. When studying these systems, the interests shifts from stability conditions, to a characterisation of the relation between the agents’ individual traits and qualitative properties of the opinion distribution in the population. Several techniques and approaches to analyse opinion formation models are proposed and applied to multiple models, one of which is new to this dissertation. The collective study of the previously mentioned interconnected systems requires the use of multiple and diverse analysis techniques and approaches, from analytical methods based on the Nyquist criterion, Bauer-Fike theorem, and Lyapunov functions to qualitative and numerical analysis techniques like histograms and binomial proportion confidence intervals. It is our hope that some of the presented results, methods, or ideas may advance the knowledge frontier in this scientific field, sparkle new research directions, and either directly or indirectly prove some value to society
Probabilistic analysis of agent-based opinion formation models
No full textWhen agent-based models are developed to capture opinion formation in large-scale populations, the opinion update equations often need to embed several complex psychological traits. The resulting models are more realistic, but also challenging to assess analytically, and hence numerical analysis techniques have an increasing importance in their study. Here, we propose the Qualitative Outcome Likelihood (QOL) analysis, a novel probabilistic analysis technique aimed to unravel behavioural patterns and properties of agent-based opinion formation models, and to characterise possible outcomes when only limited information is available. The QOL analysis reveals which qualitative categories of opinion distributions a model can produce, brings to light their relation to model features such as initial conditions, agent parameters and underlying digraph, and allows us to compare the behaviour of different opinion formation models. We exemplify the proposed technique by applying it to four opinion formation models: the classical Friedkin-Johnsen model and Bounded Confidence model, as well as the recently proposed Backfire Effect and Biased Assimilation model and Classification-based model.Team Tamas Keviczk
Classification-Based Opinion Formation Model Embedding Agents’ Psychological Traits
No full textWe propose an agent-based opinion formation model characterised by a two-fold novelty. First, we realistically assume that each agent cannot measure the opinion of its neighbours about a given statement with infinite resolution and accuracy, and hence it can only perceive the opinion of others as agreeing much more, or more, or comparably, or less, or much less (than itself) with that given statement. This leads to a classification-based rule for opinion update. Second, we consider three complementary agent traits suggested by significant sociological and psychological research: conformism, radicalism and stubbornness. We rely on World Values Survey data to show that the proposed model has the potential to predict the evolution of opinions in real life: the classification-based approach and complementary agent traits produce rich collective behaviours, such as polarisation, consensus, and clustering, which can yield predicted opinions similar to survey results.Team Tamas Keviczk
Los sentidos y el pecado original en el pensamiento de John Wyclif
No full textEl propósito principal de este artículo es presentar una aproximación a la relación entre los sentidos y el pecado original en el pensamiento de John Wyclif (c.1328-1384)2. Se comenzará por realizar un breve esbozo de la vinculación entre los sentidos y los pecados en la Edad Media, para continuar con una sucinta exposición de la figura en extremo polifacética de Wyclif y de su contexto. Los primeros apartados se basarán en bibliografía actualizada, mientras que el último se apoyará especialmente en el Tractatus de statu innocencie del pensador inglés, del año 1376.Se dedicará a extraer y analizar pasajes en los que el autor aborde los sentidos, tanto antes como después de la caída de Adán y Eva, y con ella de la humanidad toda.The main purpose of this article is to present an approach to the relationship between the senses and the original sin in the thinking of John Wyclif (c.1328-1384). It will begin by making a brief outline of the link between senses and sins in the Middle Ages, to continue with a succinct exposition of the extremely versatile figure of Wyclif and its context. The first sections will be based on updated bibliography, while the last one will especially rely upon the English thinker's Tractatus de statu innocencie, from1376. It will be devoted to select and analyse the passages in which the author addresses the senses, both before and after the fall of Adam and Eve, and with theirs, that of all humanity
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