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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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18.10.2016.

Original scientific paper

The influence of thermal treatments on the antioxidant activity and colour of chokeberry (aronia menocarpa) extract

Natural ingredients are an important trend in the present day food industry since manufacturers are demanding natural food dyes originating from concentrates of plant origin. However, if the use of plant extracts as technological additives is intended, their stability should be evaluated. This paper presents research on the stability of a 50% ethanolic extract of chokeberry (Aronia melanocarpa) from the Republic of Moldova. The extract was subjected to various thermal regimes, i.e. -2 °C for 12 hours; 4 °C for 12 hours; 40 °C for 15 minutes, 60 °C for 15 minutes, 80 °C for 15 minutes and 100 °C for 2 minutes, after which the antioxidant activity and the colour parameters (CIELab) were evaluated. Three sets of extracts were also stored for 2 weeks at -2 °C; 4 °C; and 25-30 °C and afterwards the parameters mentioned above were measured once again. Furthermore, total content of polyphenols was determined using the Folin-Ciocalteu method. The antioxidant activity was stable at temperatures under 0 °C and temperatures as high as 100°C, as well as during storage at -2 °C, 4 °C and 25-30 °C. High temperatures however decreased the value of luminosity, and increased the redness, the yellowness and the chroma value which reached a maximum value of 55.66 after the extract was subjected to 100 °C for 2 minutes. Storage at room temperature significantly affected the luminosity of the extract by increasing its value from 42.36 to 50.22. For most treatments, the colour was stable and was not significantly modified. 

Elena Cristea

01.12.2015.

Professional paper

The Atlantic diet – Origin and features

Despite globalization there still are food patterns which are clearly differentiated from one region to another in Europe and elsewhere.  In this study the Atlantic Diet is considered as thetraditional diet in Portugal and Galicia, a regionin northwest Spain.This paper aims to contribute to a better understanding of the Atlantic Diet food pattern in order to fully exploit the potential of this Atlantic gastronomical heritage.The background of the Atlantic Diet concept, the characterization of Atlantic Diet foods and a compilation of scientific findings related to the consumption of these foods are covered.A brief description of the Mediterranean Diet, the primitive pattern and the updated Mediterranean pyramid are also included in order to aid understanding of the globalization of this previously local health food pattern.Final remarks and suggestions for further studies are made.

Manuela L. Vaz-Velho, Rita Pinheiro, Ana Sofia Rodrigues

01.12.2015.

Professional paper

Pronase hydrolysis as a pretreatment for quantifying Maillard intermediates during toasting of cornflakes

Some of the products generated by the Maillard reaction are desired and very important for defining consumer acceptance of breakfast cereals. However, in recent years there has been an increased concern about compounds that are potentially harmful such as furfurals. The aim of this work was to analyze the effectiveness of protein hydrolysis with pronase as a pretreament for the evaluation of furfurals generated by the Maillard reaction during toasting of cornflakes and the parallel development of brown and fluorescent compounds. Furfurals were more accurately quantified with the pronase hydrolysis pretreatment because the protein matrix binds furfurals and fluorescent compounds. For control of the early reaction steps in the toasting process, the most sensitive parameter was fluorescence.

Mario A. Cueto, Abel E. Farroni, M. del Pilar Buera

01.12.2015.

Professional paper

A food recall case study in Australia – Towards the development of food safety applications for consumers

Changes in consumer attitudes, behaviours and purchasing preferences towards different types of food highlight the increased demand for better quality information on safety, quality and provenance of food products and on sustainability of food production processes. These changes offer both new opportunities and risks for food producers who require mechanisms to better understand and respond to changing consumers’ decision-making trends on food.  In the area of food safety, investigation of consumer and producer responses during recall incidents provide an opportunity to holistically understand existing information flows and elicit user requirements necessary for the development of more effective consumer food safety applications.This paper reports on a case study conducted with an Australian premium manufacturing company that experienced a food recall in 2014. The investigation confirms that current Australian food recall response mechanisms do not guarantee a closed loop of communication with all purchasers of a recalled product. It also highlights that producers still face difficulties in understanding how best to effectively understand and respond to different types of consumers. It emerges that recovery from a food incident relies on many factors including pre-existing brand reputation, effective information management, control mechanisms and supply chain partner response. From a consumer perspective, it is evident that consumers’ responses are influenced by various factors that require sensitivity around the choice of information modality and information platform adopted to enhance communications during food recall. The paper highlights the need for further research into understanding consumer food safety behaviours post-purchase to improve the development of consumer food safety applications.

Adeola Bamgboje-Ayodele, Leonie Ellis, Paul Turner

01.12.2015.

Professional paper

The emulsifying effect of biosurfactants produced by food spoilage organisms in Nigeria

Food spoilage organisms were isolated using standard procedures on Nutrient Agar, Cetrimide Agar and Pseudomonas Agar Base (supplemented with CFC). The samples were categorized as animal products (raw fish, egg, raw chicken, corned beef, pasteurized milk) and plant products (vegetable salad, water leaf (Talinium triangulare), boiled rice, tomatoes and pumpkin leaf (Teifairia occidentalis).They were characterised as Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas stutzeri, Burkholderia pseudomallei, Serratia rubidaea, Corynebacterium pilosum, Bacillus subtilis, Bacillus mycoides, Bacillus laterosporus, Bacillus laterosporus, Serratia marcescens, Bacillus cereus, Bacillus macerans, Alcaligenes faecalis and Alcaligenes eutrophus. Preliminary screening for biosurfactant production was done using red blood haemolysis test and confirmed by slide test, drop collapse and oil spreading assay. The biosurfactant produced was purified using acetone and the composition determined initially using Molisch’s test, thin layer chromatography and gas chromatography mass spectrometry. The components were found to be ethanol, amino acids, butoxyacetic acid, hexadecanoic acid, oleic acid, lauryl peroxide, octadecanoic acid and phthalic acid. The producing organisms grew readily on several hydrocarbons such as crude oil, diesel oil and aviation fuel when used as sole carbon sources.  The purified biosurfactants produced were able to cause emulsification of kerosene (19.71-27.14%) as well as vegetable oil (16.91-28.12%) based on the emulsification index. This result suggests that the isolates can be an asset and further work can exploit their optimal potential in industries.

Christianah O. Ogunmola, Olusimbo O. Aboaba

18.10.2016.

Original scientific paper

Antioxidant activities and inhibitory effects of free and bound polyphenols from date (Phoenix dactylifera L.) seeds on starch digestive enzymes

Date (Phoenix dactylifera L.) seeds have gained interest as a valuable by-product of the date fruit industry and have been identified as a rich source of functional and bioactive ingredients. In this study, date seeds from five varieties (Medjool, Deglet Nour, Barhee, Bou Sthammi and Dayrie) cultivated in Australia were analysed for their total phenolic and flavonoid contents, ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), and in-vitro inhibition against α-amylase and α-glucosidase. The date seed powders (DSP) were extracted with acetone-methanol-water (2:2:1, v:v:v) to obtain free polyphenols. The bound polyphenols were extracted from the residual solids with butanolHCl (97.5:2.5; v/v) treatment at 100 °C. The greatest quantities of total phenols (4166±227 mg Gallic Acid Equivalents 100g−1 DSP), total flavonoids (52.1±9.6 mg Quercetin Equivalents 100g−1 DSP), FRAP (1589±47 µmol Iron (II) Equivalents g−1 DSP) and TEAC (45.2±1.4 µmol Trolox Equivalents g −1 DSP) were detected in seeds from Deglet Nour variety. Both free and bound polyphenol fractions showed significant (p<0.05) inhibition against rat intestinal α-glucosidase with little or no inhibition against pancreatic α-amylase. Bound polyphenols showed stronger α-glucosidase inhibition compared with free polyphenols. The IC50 for α-glucosidase were reported as mg GAE mL−1 ranged from 0.39±0.02 (Deglet Nour ) to 0.68±0.02 (Medjool) for bound polyphenols, and from 0.907±0.08 (Medjool) to 1.75±0.15 (Barhee-khalal) for free polyphenols. Bound polyphenol fraction, with strong α-glucosidase inhibition and weak α-amylase inhibition, was suggested as a significant source of functional food ingredients with anti-hyperglycaemic properties.

Sameera Sirisena, Ken Ng, Said Ajlouni

18.10.2016.

Original scientific 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, Flavia C. Vargas, Julio C. de C. Balieiro, Ana Monica Q. B. Bittante, Paulo J. do A. Sobral

18.10.2016.

Original scientific 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 Foluso, Makinde A., Adeyemi I., Timothy V.

18.10.2016.

Original scientific paper

Solubility of Stevioside and Rebaudioside A in water, ethanol and their binary mixtures

In order to investigate the solubility of Stevioside and Rebaudioside A in different solvents (ethanol, water, ethanol:water 30:70 and ethanol:water 70:30), supersaturated solutions of pre-crystalized steviol glycosides were maintained at different temperatures (from 5 °C to 50 °C) to reach equilibrium. Under these conditions significant differences were found in the extent of solubility. Rebaudioside A was poorly soluble in ethanol and water, and Stevioside was poorly soluble in water. Solvent mixtures more effectively promoted solubilisation, and a significant effect of temperature on solubility was observed. The two steviol glycosides showed higher solubilities and this behavior was promoted by the presence of the other sweetener. The polarity indices of the solvents were determined, and helped to explain the observed behavior. Several solute-solvent and solute-solute interactions can occur, along with the incidence of a strong affinity between solvents. The obtained results are in accordance with technological applications of ethanol, water and their binary mixtures for Stevioside and Rebaudioside A separations.

LILIANA CELAYA, Eugenio Kolb, Nicolas Kolb

18.10.2016.

Original scientific 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 °C 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 Adekunle Olapade, Oreofeoluwatomi Adedamola Ajayi

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