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Volume 13, Issue 2, 2024

Online ISSN: 2182-1054

Volume 13 , Issue 2, (2024)

Published: 18.10.2024.

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01.12.2015.

Professional paper

Natural antioxidants isolated from Schinus areira leaves by ultrasound-assisted extraction

The aim of this study was to optimize the extraction of antioxidant compounds from Schinus areira leaves using  ultrasound assisted extraction and response surface methodology. The effect of sonication time and plant material:solvent ratio were used to optimize the recovery. Results showed that a high recovery of antioxidant compounds from leaves of three different S. areira specimens was achieved under optimized conditions. The leaf extracts obtained displayed a DPPH (1,1-Diphenyl-2-picrylhydrazyl) radical scavenging activity analogous to the well-known antioxidant trolox  (EC50 = 23-46 vs 36.1 µg/mL, respectively). In addition, these extracts showed a good potency to eliminate superoxide and nitric oxide-radicals as well as a moderate antimicrobial activity against gram positive Staphylococcus aureus and Enterococcus faecalis and yeast. HPLC chromatography analysis of the three S. areira leaf extracts showed different high contents of kaempferol-3-O-rutinoside, quercetin-3-O-galactoside and 3-O-caffeoylquinic acid. The results showed that the S. areira leaf extracts contained a high amount of antioxidant phenolic compounds, which might be a valuable source to be used as additives in plant-based foods.

Liliana S. Celaya, Carmen I. Viturro, Luís R. Silva, Silvia Moreno

01.12.2015.

Professional paper

Reproducibility and correlation between meat shear force measurements by Warner-Bratzler machine and a texturometer

Tenderness has a prominent position on meat quality and is considered to be the sensory characteristic that most influences meat acceptance. Therefore, the aim of this study was to evaluate the accuracy and determine correlations among three different meat shear force techniques. Commercial samples of bovine Longissimus thoracis et lumborum (BLTL), Tensor fasciae latae (BTFL), Semitendinosus (BST), Psoas major (BPM), Biceps femoris (BBF) and swine Longissimus thoracis et lumborum (PLTL) were analyzed for pH, proximate composition, cooking loss and shear force with a classical Warner-Bratzler device and a TA-XT2 Texturometer equipped with shear blades 1 and 3 mm thick. The effect of different techniques in each studied muscle was statistically analyzed and regression curves were built. Results from the 1 mm blade were quite similar to the ones obtained with the Warner-Bratzler, however the results from 3 mm blade were overestimated (p<0.05). Significant correlation (p<0.01) among shear force technique using Warner-Bratzler and the ones using the Texturometer was observed (0.47 for 1 mm blade and 0.57 for the 3 mm blade). In conclusion, we found that the 1 mm blade and the Warner-Bratzler machine are reproducible for all tested muscles, while the 3 mm blade is not reproducible for the BTFL, BST, BPM, BBF, PLTL. There is a significant correlation between the results obtained by the classical Warner-Bratzler and the TA-XT2 Texturometer equipped with both blades. Therefore, TA-XT2 Texturometer equipped with the 1mm blade can perfectly replace the traditional Warner-Bratzler device.

Lucas Arantes-Pereira, Flávia C. Vargas, Júlio C.C. Balieiro, Ana Monica Q.B. Bittante, Paulo J.A. Sobral

01.12.2015.

Professional paper

Modeling the kinetics of peroxidase inactivation, colour and texture changes of Portuguese cabbage (Brassica oleracea L. var. costata DC) during UV-C light and heat blanching

The effects of heat blanching and UV-C light followed by heat on Portuguese cabbage peroxidase (POD), colour and texture were studied in the temperature range of 80-95 °C. POD inactivation, lightness (L) and yellowness (b) colour changes were described by a first-order reaction model. The greenness (a) colour and texture (firmness) changes followed a two fraction kinetic model behaviour. The temperature effect was well described by the Arrhenius law.At lower temperatures the combined treatment showed higher POD inactivation. Colour and texture parameters did not show significant differences between treatments. Long processing times turned the leaves slightly darker, decreased greenness, yellowness and firmness. Short processing times increased the  firmness and greenness of the leaves. The treatment at 80 °C for 90 seconds reduced 90% of POD, retaining 98% of lightness and 92% of yellowness and improved the green colour (130%) and firmness (125%). At 80 °C the heat blanching required 7.4 min to inactivate 90% of the enzyme activity, reducing lightness, greenness, yellowness and firmness to 92%, 68%, 62% and 61%, respectively. The present findings will help to optimize the Portuguese cabbage blanching conditions.

Rui M.S. Cruz, Ana I.A. Godinho, Dilek Aslan, Necip F. Koçak, Margarida C. Vieira

01.12.2015.

Professional paper

Bioactive components, antioxidative properties and inhibition of Fe2+-induced lipid peroxidation of mango peel as affected by the storage of mango fruit

This study sought to evaluate the bioactive components (total phenolics, vitamin C and flavonoid), antioxidant properties (FRAP, and hydroxyl, DPPH and ABTS radical scavenging abilities) and inhibition of Fe2+-induced lipid peroxidation of the peel of mango fruit stored at refrigeration temperature and room temperature. The peel of mango fruit stored at room temperature had significantly (P ≤ 0.05) higher contents of total phenolic (13.61 mg GAE/g), vitamin C (12.98 mg AAE/g), total flavonoid (4.49 mg QE/g) and non-flavonoid (9.12 mg Qe/g) than the peel of freshly harvested mango fruit and the peel of mango fruit stored at refrigeration temperature. In consonance with the bioactive components, the peel of mango fruit stored at room temperature had a higher FRAP, and hydroxyl, DPPH and ABTS radical scavenging abilities than the others. The peel of mango fruit stored at room temperature showed stronger inhibition of Fe2+ induced lipid peroxidation by exhibiting the least IC50 (1.44 mg/ml in brain), (1.43 mg/ml in pancreas) and (1.88 mg/ml in kidney). Thus freshly harvested, matured, edible and just ripe mango fruit (Sheri Mango) could be stored at room temperature and be consumed with the peel.

Adetuyi O. Foluso, Akinlerye Makinde, Ifedayo Adeyemi, Victoria Timothy

01.12.2015.

Professional paper

Effect of roasting regime on phytochemical properties of Senna occidentalis seeds

Senna occidentalis seeds were roasted at varying temperatures of 190, 210 and 230 oC each for 10, 15 and 20 min. Phytochemicals of the roasted seeds were determined using standard methods. The phytochemicals analysed were tannins, saponins, flavonoids, alkaloids, glycosides, oxalate and phenolics. Phytochemicals are compounds hypothesized for much of the disease-protection provided by diets high in fruits, vegetables, legumes, cereals and plant-based beverages. This study has clearly shown that roasting time and temperature have significant effects on the seed parameters analyzed. There was an increase in tannin, alkaloid, saponin and phenolic contents and a decrease in the contents of flavonoids and oxalates.

Abiodun A. Olapade, Oreofeoluwatomi A. Ajayi

18.04.2015.

Original scientific paper

Enhancing food engineering education with interactive web-based simulations

In the traditional deductive approach in teaching any engineering topic, teachers would first expose students to the derivation of the equations that govern the behavior of a physical system and then demonstrate the use of equations through a limited number of textbook examples. This methodology, however, is rarely adequate to unmask the cause-effect and quantitative relationships between the system variables that the equations embody. Web-based simulation, which is the integration of simulation and internet technologies, has the potential to enhance the learning experience by offering an interactive and easily accessible platform for quick and effortless experimentation with physical phenomena. This paper presents the design and development of a web-based platform for teaching basic food engineering phenomena to food technology students. The platform contains a variety of modules (“virtual experiments”) covering the topics of mass and energy balances, fluid mechanics and heat transfer. In this paper, the design and development of three modules for mass balances and heat transfer is presented. Each webpage representing an educational module has the following features: visualization of the studied phenomenon through graphs, charts or videos, computation through a mathematical model and experimentation. The student is allowed to edit key parameters of the phenomenon and observe the effect of these changes on the outputs. Experimentation can be done in a free or guided fashion with a set of prefabricated examples that students can run and self-test their knowledge by answering multiple-choice questions.

Alexandros Koulouris, Georgios Aroutidis, Dimitris Vardalis, Petros Giannoulis, Paraskevi Karakosta

18.04.2015.

Original scientific paper

Sensory evaluation of aromatic foods packed in developed starch based films using fuzzy logic

The last two decades have seen attempts to replace non biodegradable, synthetic food packaging films with alternatives made from biopolymers. The objective of the present work was to evaluate sensory quality of tea leaf and culinary tastemaker powder when sealed in pouches based on starch films. Films were developed from corn starch and a functional polysaccharide (FP) from amylose (AM), methylcellulose (MC), and hydroxypropylmethylcellulose (HPMC), using a casting technique. Pouches were stored inside a secondary package (plastic jar) under ambient condition for 90 days. Sensory attributes of the stored food samples were evaluated (tea in liquor form) and the scores analysed by fuzzy logic. Results were compared with similarly stored foods but using market available poly-pouches as packaging material.
For tea and tastemaker in general, the relative importance of the sensory attributes under consideration was assessed as: aroma (Highly important) > taste (Highly important) > colour (Highly important) > strength (Important) for tea, and taste (Highly important) > aroma (Highly important) > colour (Important) > appearance (Important) for tastemaker. Among the three films that were developed, the highly important sensory attributes of aroma and taste were maintained as ‘Very good’ when the foods were packed in starch–HPMC/AM film. When the products were packed in market-available polypouches they exhibited similar attributes. With the exception of ‘Very good’ maintenance of the colour of tastemaker by the commercial pouch, irrespective of film and food, the colour and strength/appearance were retained in the ‘Good’-‘Satisfactory’ range. The overall sensory score of tea was also maintained as ‘Very good’ in starch-HPMC film. 

Tanima Chowdhury, Madhusweta Das

18.04.2015.

Original scientific paper

A methodology to promote business development from research outcomes in food science and technology

Valorization of knowledge produced in research units has been a major challenge for research universities in contemporary societies. The prevailing forces have led these institutions to develop a “third mission”, the facilitation of technology transfer and activity in an entrepreneurial paradigm. Effective management of challenges encountered in the development of academic entrepreneurship and the associated valorization of knowledge produced by universities are major factors to bridge the gap between research and innovation in Europe. The need to improve the existing institutional knowledge valorization processes, concerning entrepreneurship and business development and the processes required were discussed. A case study was designed to describe the institutional knowledge valorization process in a food science and technology research unit and a related incubator, during a five year evaluation period that ended in 2012. The knowledge valorization processes benefited from the adoption of a structured framework methodology that led to ideas and teams from a business model generation to client development, in parallel, when possible, with an agile product/service development. Although academic entrepreneurship engagement could be improved, this case study demonstrated that stronger skills development was needed to enable the researcher to be more aware of business development fundamentals and therefore contribute to research decisions and the valorisation of individual and institutional knowledge assets. It was noted that the timing for involvement of companies in the research projects or programs varied with the nature of the research.

Eduardo Cardoso

18.04.2015.

Original scientific 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, Nıvea M. Vicentini, Rodolfo M.C. Dos Santos, Ana Monica Q.B. Bittante, Paulo J.A. Sobral

18.04.2015.

Original scientific 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/Caco2 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-α 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 nondairy 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 Chafer, Amparo Chiralt, Jose Moises Laparra, Chelo Gonzalez-Martıne

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