Current issue
Volume 13, Issue 2, 2024
Online ISSN: 2182-1054
Volume 13 , Issue 2, (2024)
Published: 18.10.2024.
Open Access
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Contents
01.12.2014.
Professional paper
Food innovation and entrepreneurship in higher education: a case study
Susana C. Fonseca, Rita Pinheiro, Carla Barbosa, Alberta Araújo, Manuela Vaz-Velho, Rui Alves
01.12.2014.
Professional paper
Simple and double microencapsulation of Lactobacillus acidophilus with chitosan using spray drying
Isela A. Flores-Belmont, Enrique Palou, Aurelio López-Malo, María Teresa Jiménez-Munguía
01.12.2014.
Professional paper
Teaching microbiological food safety through case studies
Florence Dubois-Brissonnet, Laurent Guillier, Murielle Naïtali
01.12.2014.
Professional paper
Identifying most important skills for PhD students in Food Science and Technology: a comparison between industry and academic stakeholders
Chelo González-Martínez, Peter Ho, Luis Cunha, Oliver Schluter, Paola Pittia
18.10.2014.
Original scientific paper
Characterization of potent odorant compounds in Turkish olive oils by GC-MS-olfactometric techniques
The purpose of this study was to determine the most powerful aroma-active compounds of olive oils obtained from Ayvalik (AYV), Gemlik (GEM) and Memecik (MEM) cultivars harvested in 2011, using gas chromatography-mass spectrometry-olfactometry (GC-MS-O). Simultaneous distillation and extraction (SDE) with dichloromethane was used for extraction of volatile components. The aromaactive compounds of olive oils were evaluated by aroma extract dilution analysis (AEDA). A total of 14, 12 and 12 aroma-active compounds within the range of ≥64–1024 flavor dilution (FD) factors were detected in aromatic extracts of olive oils obtained from AYV, GEM and MEM cvs., respectively. The compounds having the highest FD factor (1024) were (Z)-3-hexenol (cut grass, herbal) and βsesquiphellandrene (floral) for AYV oil and (Z)-3-hexenyl acetate (fruity) for MEM oil. Among these compounds, terpenes were the overwhelmingly largest aroma-active components followed by aldehydes.
Songul Kesen, Hasim Kelebek, Serkan Selli
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
18.10.2014.
Original scientific 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 4
th 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 .Convective heat transfer
Jose Rabi, Evelyne Derens-Bertheau, Elisabeth Morelli, Isabelle Trezzani-Harbelot
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
18.10.2014.
Original scientific paper
Functional properties of proteins isolated from industrially produced sunflower meal
Protein isolate 1 (PI1) and protein isolate 2 (PI2) were prepared from industrially produced sunflower meal by using isoelectric and ethanol precipitation respectively. The water absorption capacity of PI1 was 6 times higher than that of PI2 and was significantly reduced by the presence of 0.03 M and 0.25 M NaCl. Oil absorption capacity of both protein isolates was not influenced by NaCl supplementation. Foam capacity of PI1 and PI2 was pH-dependent. While the foam capacity of both isolates was improved by either 0.03 M or 0.25 M NaCl, the foam stability was negatively influenced by the addition of NaCl at all pH values with except for pH 4. Emulsifying activity of PI1 and PI2 was lowest at pH 4. The emulsions exhibited relatively high stability (> 90%) under all studied conditions. Knowledge of the influence of pH and boundary concentrations of NaCl on the functionality of sunflower meal protein isolates could be beneficial for their future potential application in food industry.
Petia Ivanova, Vesela Chalova, Lidia Koleva
18.10.2014.
Original scientific paper
Evaluation of cookies produced from blends of wheat, cassava and cowpea flours
Cassava (Manihot esculenta Crantz) and cowpea (Vigna unguiculata L. Walp) were processed into flours and used to substitute wheat flour for preparation of cookies. The chemical, including proximate composition and anti-nutritional factors, and functional and pasting properties of the blends were determined. Cookies were produced from the blends with 100% wheat flour as a control. The antinutritional factors, physical properties and organoleptic attributes of the cookies were evaluated. An increase in the level of cassava flour substitution resulted in a decrease in the protein content of the composite flour. However, addition of cowpea flour resulted in an increase in the protein content. There were significant (p<0.05) reductions in the studied anti-nutritional factors after baking. Cookies from composite flours were not significantly (p>0.05) different from the control in overall acceptability. This indicates the feasibility of producing nutritious cookies with desirable organoleptic qualities from cassava, wheat and cowpea composite flour.
Abiodun Olapade, Adeyemo Abimbola Mary