Contents
01.12.2014.
Professional paper
Information literacy training in AgroParisTech food studies
AgroParisTech professors and librarians in Food Science and Technology have developed information literacy instruction to help students find and use relevant information. The course trains students to develop information literacy competencies: to identify the information needed and define its nature and extent; to access the information with efficiency because they select and use methods, resources and retrieval systems most appropriate to the topic; to evaluate the used methods, information, and sources; to search, access and use information ethically and legally; to read, use and write bibliographic references.AgroParisTech trains two kinds of students. For Higher Education students (engineering students), the training takes place at their arrival in AgroParisTech, including courses and practical classes: role and management of information in organizations; information on plagiarism; resources in environment, food science and technology; use of relevant tools and methods for searching in databases; reference writing.For students attending a Master of Science, the training prepares them to produce a literature review. The curriculum includes: information about scientific integrity, plagiarism; information needed for a researcher; critical reading of a journal article; how to manage a literature review: resources used, information search with databases, full text access; reference writing.The students will use these information literacy skills along their studies as well as in their future jobs.
Agnès Grimal, Florence Dubois-Brissonnet, Elisabeth Dumoulin
01.12.2014.
Professional paper
Mechanical properties of cassava starch films as affected by different plasticizers and different relative humidity conditions
The influence of plasticizer type (glycerol and sorbitol), its content (starch:plasticizer ratio of 1:0.15; 1:0.20; 1:0.25 and 1:0.30) and the relative humidity conditions (43, 58, 75 and 85%) on the mechanical properties of cassava starch films was studied. Both plasticizers seemed to integrate homogeneously in the film matrix. The incorporation of different concentrations of plasticizers affected the mechanical properties of the cassava starch films. Plasticizer ratio directly influenced the force values of the films, they showed significant flexibility when the plasticizer proportion was increased in the formulation. Under conditions of low relative humidity, sorbitol produced films more resistant to puncture than glycerol. Qualitatively, all the films were less brittle when the plasticizers were incorporated.
Jeannine Bonilla Lagos, Nívea M. Vicentini, Rodolfo M.C. Dos Santos, Ana Mônica Q.B. Bittante, Paulo J. A. Sobral
01.12.2014.
Professional paper
Simple and double microencapsulation of Lactobacillus acidophilus with chitosan using spray drying
The aim of this study was to evaluate the survival of Lactobacillus acidophilus that had been simple or double spray dried using chitosan to cause microencapsulation and which had been exposed to model gastrointestinal conditions. In addition, the study also determined the physicochemical properties of the powder containing the microencapsulated probiotic.Chitosan-inulin or chitosan-maltodextrin (1:15 or 1:25) solutions were inoculated with 1012 cfu mL-1 of L. acidophilus, for simple microencapsulation. The different solutions were dried using a spray dryer with an inlet air temperature of 130°C and a solution flux of 4.8 g min-1. A two-step process was used for the double microencapsulation. In the first step, the probiotic was added to a gelatin-maltodextrin (1:25) solution and then spray dried; for the second step, the microencapsulated probiotic was added to a chitosan-inulin or chitosan-maltodextrin (1:25) solution and then it was spray dried again.With the simple microencapsulated probiotic, a microbial reduction of 7 log cycles was obtained. With the double microencapsulated probiotic only 3 log reductions were achieved. The double microencapsulated probiotic thus demonstrated greater resistance to simulated gastrointestinal conditions. The powders produced were shown to have water activity values of 0.176 - 0.261 at 25 °C and moisture content of 0.8 – 1.0%, which are characteristic of spray dried products. The bulk density was significantly (p < 0.05) lower (300 kg m-3) for simple than for double (400 kg m-3) microencapsulated probiotic powders. Solubility and dispersibility of the powder microcapsules were better at lower pH values.Double microencapsulation using a process of spray drying is therefore recommended for probiotics, thus exploiting chitosan’s insolubility in water, which can be applied for the of development food products.
Isela A. Flores-Belmont, Enrique Palou, Aurelio López-Malo, María Teresa Jiménez-Munguía
01.12.2014.
Professional paper
Food innovation and entrepreneurship in higher education: a case study
Food innovation and entrepreneurship are important topics in graduate food studies. Students should be challenged to promote an innovative attitude towards their future career in the food industry sector, as professionals working in a small and medium-sized enterprise, or in a large multinational company, or even as entrepreneurs with their own working projects. The present case study shows a curricular unit of a master course that intends to integrate the knowledge on new and sustainable technologies and products, based on seminars of experts on hot topics, on visits to food industry enterprises and market expositions and on the development of a state-of-the-art report about an emergent or novel food technology or product with oral presentation. Hot topic seminars included edible coatings, bioprocessing, allying tradition and innovation in food products, new convenience foods, challenging tests, and new clean and sustainable processes. Entrepreneur alumni lectures were also promoted allowing exchange of experiences. Visits included a high pressure technology unit of a food industry, an innovation and development department of a food industry, an entrepreneurship centre and a food exhibition. A satisfaction survey was made, through the response of a questionnaire by the students, proving the effectiveness and success of this unit course framework. A SWOT analysis was carried out to gain a better understanding of the strengths, weaknesses, opportunities, and threats involved in the curricular unit objectives.
Susana C. Fonseca, Rita Pinheiro, Carla Barbosa, Alberta Araújo, Manuela Vaz-Velho, Rui Alves
01.12.2014.
Professional paper
Effect of incorporating alum in cane juice clarification efficiency and sucrose losses
The effect of incorporating alum in the clarification stage of raw juice in sugarcane processing on the juice quality and sucrose loss was investigated. Alum was incorporated in both intermediate and hot liming clarification processes of cane juicing. One portion of the cane juice was used for With Pre-treatment Treatment (WPT) while the other portion constituted No Pre-treatment (NPT) juice. Alum at levels of 0 mg L-1, 50 mg L-1, 100 mg L-1 and 150 mg L-1 was incorporated in both intermediate and hot liming clarification processes in each of the two cane juice portions. Sugar concentration (sucrose, glucose and fructose), oBrix, pH, colour, settling performance (initial settling rates (ISR), final mud volume (MV∞), and turbidity) and residual aluminium ion concentration were evaluated. Any significant variations (p < 0.05) in these parameters were assessed. The study found significantly lower (p < 0.05) sucrose losses in clarified juice from intermediate liming of WPT after alum treatment than in the rest of the clarified juices. Colour and turbidity in the pre-treated cane juice of intermediate liming was reduced by 36.9% and 98.1%, respectively at 150 mg L-1 alum level. An initial settling rate of 260 mL min-1 in WPT cane juice of intermediate liming at 150 mg L-1 alum level resulted in the most compact final mud volume of 10.3%. The residual aluminium concentration (0.025 to 0.048 mg L-1) in alum treated clarified juices was lower than the natural aluminium concentration (0.088 mg L-1) in untreated cane juice. This study showed the potential for the use of alum in cane juice clarification to improve on clarification efficiency and lower sucrose loss.
Benard M. Kimatu, Symon Maina Mahungu, Abdul K. Faraj, Symon M. Mahungu, Benard Muinde Kimatu
01.12.2014.
Professional paper
Almond milk fermented with different potentially probiotic bacteria improves iron uptake by intestinal epithelial (Caco-2) cells
New fermented almond milks were developed, using different potentially probiotic bacteria, in order to meet the current demand for healthy, versatile non-dairy products. An in vitro digestion/Caco-2 cell model was used to evaluate the effect of both non-fermented and fermented almond milks on the mitochondrial enzymatic activities of enterocytes. Moreover, macrophages were challenged with the in-vitro digested samples and the production of pro-inflammatory biomarkers TNF-a and IL-6 was quantified. Enzymatic activities of cell cultures seemed to be stimulated by the exposure to both fermented and non-fermented almond milks. Both biomarkers decreased (p< 0.05) in fermented almond milks with either B. bifidum or B. longum. Results showed that fermented almond products favored the energetic metabolism of enterocytes and had a lower inflammatory response than non-fermented almond milk, suggesting its benefits for the management of allergies/intolerances. Moreover, the fermentation process enhanced the uptake of iron by Caco-2 cells, especially when using L. rhamnosus and either B. bifidum or B. longum as starters, thus improving the product bioactivity. Therefore, new non-dairy fermented products with functional properties were developed, which might be positioned as alternatives to cow-milk products for sensitized groups of population (allergic and/or intolerant to cow milk or anemic population, among others).
Neus Bernat, Maite Cháfer, Amparo Chiralt, Jose Moisés Laparra, Chelo González-Martínez
18.10.2014.
Original scientific paper
PhD competences of food studies
In European Higher Education, learning outcomes and competences have been used sometimes with different meanings and sometimes with the same meaning. But both terms have been more commonly used to refer to knowledge, understanding and abilities a student must demonstrate at the end of a learning experience. Their use is a consequence of the paradigm shift of the Bologna Process to a learner centered education environment. The definition of standards of competences (or learning outcomes) for the PhD degree is thus a need for the quality assurance of this degree. In this work, subject-specific and generic competences for the PhD in Food Science and Technology and their alignment with the European Qualifications Framework (EQF) level descriptors for quality assurance purposes have been identified.
Chelo Gonzalez-Martinez, Cristina L.M. Silva, Rui Costa
18.04.2014.
Original scientific paper
Popping characteristics of paddy using microwave energy and optimization of process parameters
Microwave popping characteristics of a particular variety of paddy were studied using a domestic microwave oven. The experiments were carried out at 4 levels of moisture content (around 13%, 14%, 15% and 16% wb), 3 levels of power (600 W, 850 W and 1000 W) and 5 levels of heating time (40 s, 60 s, 80 s, 100 s and 120 s). A general factorial experiment design was followed, and effect of different treatment combinations on popping percentage and expansion ratio of the paddy was evaluated. The maximum popping percentage of 63.47% was obtained at a moisture content of 14.15% and energy level of 80 kJ (1000 W and 80 s) while the maximum expansion ratio of 4.42 was obtained at 14.94% moisture content and energy level of 68 kJ (850 W and 80 s). Optimum values of microwave power, time of heating and moisture content of paddy were achieved at 1000 W, 80 s and 15%, respectively, corresponding to popping percentage and expansion ratio of 58.73 and 3.58.
Ajay Kumar Swarnakar, M. Kalpana Devi, Susanta Das
18.10.2014.
Original scientific paper
Variation of physicochemical and sensory properties during the aging of yerba mate
Yerba mate infusion is widely consumed in Argentina, Brazil and Paraguay. One of the processing steps used in Argentina is aging. The following three methods were used to age yerba mate: 1) air humidity and temperature-controlled aging; 2) temperature-controlled aging and 3) no control. The aim of this research was to determine the physicochemical and sensory attribute differences when yerba mate was aged using these three methods. The concentration of caffeine, glucose, fructose, maltose and phenolic compounds and pH diminished in all three aging methods but by different percentages. The sensory attributes did not exhibit uniform behaviour. Astringency remained constant in the first method and diminished in the other two. Bitterness increased in all three methods but by different percentages. Sweetness diminished in all three methods. Notably few correlations were determined between physicochemical and sensory attributes.
Santiago A. Holowaty, Sergio A. Surkan, Valeria D. Trela, German D. Byczko, Miguel E. Schmalko
01.12.2013.
Professional paper
Blast-cooling of beef-in-sauce catering meals: numerical results based on a dynamic zero-order model
Beef-in-sauce catering meals under blast-cooling have been investigated in a research project which aims at quantitative HACCP (hazard analysis critical control point). In view of its prospective coupling to a predictive microbiology model proposed in the project, zero-order spatial dependence has proved to suitably predict meal temperatures in response to temperature variations in the cooling air. This approach has modelled heat transfer rates via the a priori unknown convective coefficient hc which is allowed to vary due to uncertainty and variability in the actual modus operandi of the chosen case study hospital kitchen. Implemented in MS Excel®, the numerical procedure has successfully combined the 4th order Runge-Kutta method, to solve the governing equation, with non-linear optimization, via the built-in Solver, to determine the coefficient hc. In this work, the coefficient hc was assessed for 119 distinct recently-cooked meal samples whose temperature-time profiles were recorded in situ after 17 technical visits to the hospital kitchen over a year. The average value and standard deviation results were hc = 12.0 ± 4.1 W m-2 K-1, whilst the lowest values (associated with the worst cooling scenarios) were about hc » 6.0 W m-2 K-1.
Jose A. Rabi, Evelyne Derens-Bertheau, Elisabeth Morelli, Isabelle Trezzani-Harbelot
