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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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18.10.2015.

Original scientific paper

In vitro health beneficial activities of Pumpkin seeds from Cucurbita moschata cultivated in Lemnos

Pumpkin seeds are commonly consumed in Greece. Although Cucurbita moschata is locally grown in Lemnos and is traditionally used in pumpkin pies, the seeds are currently discarded after consumption of the fruit flesh. The aim of the present study was to investigate the nutritional functionality of pumpkin seeds from Cucurbita moschata grown in Lemnos. Cucurbita moschatas’ seeds, raw or roasted, were appropriately extracted and the results are presented for raw versus (vs) roasted seed extracts. The phenolic content was expressed as µg gallic acid/g of seeds according to Folin-Ciocalteau assay (370.3 ± 19.1 vs 551.0 ± 22.0). Antioxidant capacity was expressed as equivalent amount for 50% scavenging in mg of seeds for DPPH (50.03 ± 5.91 vs 25.82 ± 6.77) and ABTS (17.85 ± 0.77 vs 12.77 ± 0.76) assays, and as µmol of trolox/g of seeds for FRAP (1.19 ± 0.05 vs 2.50 ± 0.23) and CUPRAC (2.13 ±0.11 vs 3.25 ± 0.06) assays. Antiinflammatory/antithrombotic and anti-diabetic activities were expressed as mg of seeds for 50% inhibition of platelet activating factor (0.62 vs 0.15) and as µg of seeds for 25% inhibition of alpha-glycosidase (40.0 vs 61.0) activities respectively. Moreover, anti-atherogenic activity was expressed as the % increase in lag time of human plasma oxidation (62.7 versus 163.2) Raw and roasted pumpkin seed extracts exert anti-oxidant, anti-thrombotic/anti-inflammatory, antiatherogenic and antidiabetic activities. Cucurbita moschata seeds may represent a novel opportunity for development of functional foods, with a local interest in Lemnos that would contribute also to the regional public health improvement. 

Danai Sakka, HARALABOS KARANTONIS

18.04.2015.

Original scientific paper

Applicability of Mixolab test with local wheat flours

Several types of equipment have been used to predict dough behaviour during breadmaking. The complexity of requirements means that no device is able to predict all the properties, and therefore, new tests are released continuously. The Chopin Mixolab mixes the dough at different temperatures, allowing the study of dough mixing properties, weakening, gelatinization, gel stability and retrogradation in one test. The objective of this work was to study the suitability of the Mixolab to predict rheological properties and breadmaking quality of local wheats. Flour was obtained from 29 wheat samples from different genotypes and environments. The correlation of results from traditional analyses (test weight, protein content, sedimentation volume, wet gluten, Falling Number, Alveograph and Farinograph) with Mixolab parameters was studied. The properties of two different bread types were compared with all these parameters. Stability and water absorption values from the Farinograph were highly correlated with the respective Mixolab parameters. It was concluded that wheat samples could be sorted by mixing properties in similar order independently of which method was used. Beyond that, gluten strength estimators obtained from these three rheological methods and the sedimentation volume test were highly correlated. Whilst the correlation of Mixolab parameters with pan loaf volume was not as high as traditional ones, Mixolab developing time, stability and C5 were the best correlated with the most important hearth bread characteristics. Studies performed by other researchers, using wheats from diverse origins, found different results. The need for empirical rheology evaluation with local wheat samples was proved.

Daniel Vazquez, Marıa C. Veira

18.04.2015.

Original scientific paper

Lipid composition of seed oils of different pomegranate (Punica granatum L.) cultivars from Spain

Pomegranate (Punica granatum L.) is an ancient fruit tree traditionally cultivated in the Near and Middle East. Presently, its most important growing regions include Afghanistan, Iran, Israel, USA, Italy and Spain, the latter country the largest European exporter. The pomegranate fruit can be divided into several anatomical compartments: outside peel, inside peel, and arils (pulp and seeds), the last part being usually used for consumption as is or for juice, jams and jellies production. Even though pomegranate seeds are an industrial by-product, recent reports have highlighted their potential use as a source of oil with beneficial chemical attributes. Therefore, the main objective of the present work was to characterize the seed oil of nine European pomegranate varieties, collected in Spain, for their fatty acid and vitamin E compositions. All seed lipid fractions consisted mainly of punicic acid (c9,t11,c13 C-18:3), ranging between 77.3% and 83.6% of total fatty acids, followed by small amounts of linoleic acid (C18:2n6), oleic acid (C18:1n9) and palmitic acid (C16:0). Regarding vitamin E composition, α-, γ-, δ-tocopherols were found in all pomegranate seed oils, but mainly γ-tocopherol, with total tocopherols ranging from 174.5 to 627.3 mg/100g oil. The richness of these pomegranate varieties seed oils in punicic acid, a conjugated linolenic acid with interesting anti-carcinogenic activity, and the elevated amount of tocopherols on the extracted lipids, of technological and nutritional relevance, make this by-product interesting for further exploitation.

Luana Fernandes, Jose A. Pereira, Isabel Lopez-Cortes, Domingo M. Salazar, Elsa Ramalhosa, Susana Casal

18.04.2015.

Original scientific paper

Evaluating the Ultra-High Pressure Homogenization (UHPH) and Pasteurization effects on the quality and shelf life of donkey milk

Donkey milk has functional properties of great interest to human nutrition. The effects of ultra-high pressure homogenization (UHPH) at 100 MPa, 200 MPa and 300 MPa in comparison with different pasteurization treatments of 70 ◦C for 1 min and 85 ◦C for 1 min on the physicochemical quality and shelf-life of treated and raw (untreated) donkey milk were studied. Gross composition and pH, total mesophilic counts, lysozyme activity and physical stability were studied during storage at 4 ◦C for 28 days. The compositional profile showed resemblance to that of human milk characterized by high lactose, low fat and low protein content and was least affected by the treatments. UHPH treatments at 200 MPa, 300 MPa and 85 ◦C were able to maintain steady pH during storage whereas the low intensity treatments showed a significant decrease. The observed lysozyme activity in the samples was generally high and appeared to have been enhanced by the applied UHPH and pasteurization treatments with no significant change during storage. Although the raw milk showed good initial microbial quality, extensive growth of mesophilic microorganisms occurred after 7 days of storage, unlike the treated samples which were able to maintain significantly low counts throughout the storage period. The physical stability of milk was negatively influenced by the higher UHPH treatments of 200 MPa and 300 MPa which exhibited sedimentation phenomenon, while creaming was insignificant.

Cephas Nii Akwei Addo, Victoria Ferragut

18.10.2015.

Original scientific paper

Microencapsulation of steviol glycosides (Stevia rebaudiana Bertoni) by a spray drying method – Evaluation of encapsulated products and prepared syrups

The aim of this study was to encapsulate the steviol glycosides (SGs), derived from Stevia rebaudiana (Bert) Bertoni leaves, by applying a spray-drying method. The purpose was to minimize the bitter aftertaste of the SGs as well as to ameliorate/improve their properties. The encapsulation agents used were maltodextrin (19 DE) and inulin in a ratio of 80 : 20, while three levels of SGs in total solids (1.5, 2.5 and 3.5 %) were studied. The encapsulated SGs products were evaluated for their hygroscopicity, solubility, moisture content and microencapsulation efficiency (MEE %). Also, syrups prepared with encapsulated SGs, at 1 % w/v, were tested for their viscosity, refractive index, turbidity and sensory properties. Significant differences (P<0.05) in MEE %, moisture content, hygroscopicity and solubility values of the encapsulated SGs products were observed depending on the level of SGs in total solids. In particular, the MEE %, the hygroscopicity and the solubility values ranged from 62.36, 82.46 to 94.67 %, 21.51, 26.67 and 24.25 % and 99.93, 97.50 to 96.03 % for encapsulated SGs products produced with 1.5, 2.5 and 3.5 % SGs in total solids, respectively. The encapsulated product produced with 2.5 % steviol glycosides in total solids presented the most appealing sensory and quality characteristics.

Charikleia Chranioti, Sofia Chanioti, Constantina Tzia

18.10.2015.

Original scientific 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 Lopez-Malo, María Teresa Jiménez-Munguía, Aurelio Lopez-Malo

01.12.2013.

Professional paper

Effect of Buckwheat Processing Products on Dough and Bread Quality Made from Whole-Wheat Flour

The paper gives a brief overview of the current nutritional status of the Ukrainian population and describes useful buckwheat properties. The objective of the paper is to study the effect of buckwheat processing products (flour and flakes) on the technological process and quality of bread made from whole-wheat flour. This paper describes and analyzes research data on the rheological properties of dough samples which were determined by farinograph and amylograph.Investigation of structural and mechanical properties of dough showed an increase in water-absorbing capacity in all samples when adding buckwheat products. Moreover, dough made with buckwheat flakes has a lower value of mixing tolerance index (by 47 %) than dough made from buckwheat flour, and a higher valorimetric value (by 20 %). Determination of dough properties by amylogram has shown that a sample containing buckwheat flakes has a higher maximum viscosity than a sample containing buckwheat flour. Determination of the gas-production and gas-retention capacity of dough is also presented, along with an analysis of the quality of finished products based on the results of laboratory baking tests.The samples of bread supplemented with buckwheat flakes have better shape stability (by 21 %), specific volume (by 12 %) and porosity (by 11 %) than bread made from buckwheat flour. The organoleptic evaluation of finished product quality has shown that bread supplemented with buckwheat flakes has a more fluffy-texture, elastic crumb and uniform porosity than bread made from buckwheat flour. Buckwheat flakes proved to have a better effect on parameters of the technological process and quality of bread when compared with buckwheat flour.

Vira Drobot, Anastasiya Semenova, Jelyzaveta Smirnova, Larisa Mykhonik

01.12.2013.

Professional 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 LM Silva, Rui Costa

01.12.2013.

Professional paper

Dried Fruit Matrices Incorporated with a Probiotic Strain of Lactobacillus plantarum

The development of fruits and vegetables containing probiotics is a topic of great interest and popularity for health-conscious consumers. The aim of this study was to evaluate the possibility of using dried fruit matrices as delivery vehicles for probiotics. Different fruits — kiwi, mango, strawberry, pineapple, banana — were used as food matrices to test the viability of a strain of Lactobacillus plantarum, which was determined after drying at 40ºC and at different storage times. Cell survival after drying decreased by ca. 1 log in banana and strawberry, to 3 log, for kiwi. The bacterial numbers in banana and strawberry dried pieces at the time of storage at room temperature and 4ºC were approximately 107 cfu/g. After 37 days storage at room temperature, no viable counts were observed in any of the fruits studied. However, at 4ºC after this period of time, viable cells were detected for all the fruits (1.9x106 cfu/g, 1.5x105 cfu/g 1.5x105 cfu/g, 4.7x104 cfu/g 8.0x103 cfu/g, for strawberry, banana, kiwi, mango and pineapple, respectively).

Catarina Ribeiro, Ricardo Freixo, Joana Silva, Paul Gibbs, Alcina Morais, Paula Teixeira

01.12.2013.

Professional 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 Alexi Holowaty, Sergio Alejandro Surkan, Valeria D. Trela, German Darío Byczko, Miguel Eduardo Schmalko

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