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  • Author: Cristina Damian x
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Influence of dietary fiber addition on some properties of yoghurt

Abstract

The objective of this work was to study the effect of different dietary fibers on rheological properties of yoghurts fortified with these fibers [1, 2, 3]. Commercial fibers from apple and inulin were used. The effect of addition of dietary fibers in yoghurt [4, 5] was investigated by a rotational viscometer, Brookfield viscometer (Brookfield Engineering Inc., Model RV-DV I Prime) with RV spindles. The Brookfield viscometer DV I Prime with disk spindles represents an easy and cheap method for rheological characterization of non-Newtonian fluids, in this case of yoghurt. Syneresis and pH did not show any difference, while only apple fiber yoghurt showed colour differences compared to control.

Open access
Environmental pollution in the petroleum refining industry

Abstract

The petroleum refining industry has a significant influence on the total pollution of the environment by industrial discharges and wastes. In the operation of petroleum refineries, the atmosphere is polluted with hydrogen sulfide, sulfur dioxide, nitrogen oxides, carbon monoxide, hydrocarbons, and other toxic substances. The main pollutants are sulfur dioxide and hydrocarbons. The fresh water used by refineries in product cooling is returned to the original source of water containing crude oil, petroleum products, and mineral salts as contaminants. The extent of air and water pollution depends on the particular processing technology, control measures that are employed and also on the scale of the processing. In working out these measures, the primary attention of scientific-research institutes and design and planning organizations must be directed not only towards how to reduce the contaminating and poisoning action of industrial discharges on the environment, but primarily towards preventing or minimizing these discharges in the refineries.

Open access
Effect of thermal treatment on antioxidant activity and colour of carrot purées

Abstract

Total antioxidant activity, levels of bio-active compound groups and instrumental colour of carrot purée subjected to thermal treatment (70°C/2 min) were measured. The method applied to the dosage of ascorbic acid was with 2,6-diclorophenolindophenol. Total phenols (TP) in purée were determined using the Folin- Ciocalteau method and antioxidant activity by the use of DPPH free radical method. The colour of the samples was measured using a Hunter-Lab colour meter. Heat treatment caused a rapid decrease in ascorbic acid. Phenolic contents were in general unaffected by thermal treatment. Colour parameters were significantly affected by thermal treatment. This provides a helpful tool for understanding the effect of processing on colour variation of carrot purée in a broader spectrum. Industrial relevance: This research paper provides scientific evidence of the influence of thermal treatments in retaining important bioactive compounds.

Open access
Determination of essential and toxic elements, ascorbic acid content and color of different leaves in two cabbage varieties

Abstract

The main goal of this paper was to evaluate total macro- and microelement contents of different cabbage leaves of two varieties of cabbage (Brassica oleracea var. capitata f. alba and Brassica oleracea var. capitata f. rubra) and to determine the ascorbic acid content and color parameters (L*, a*, b* and -ΔE). Also, the anthocyanins content of Brassica oleracea var. capitata f. rubra was investigated. The highest mean contribution of elemental interactions regarding total macroelements in white cabbage leaves from inside (14-16 leaf), was observed for calcium and selenium, whereas the lowest was found for heavy metals, nickel, cadmium, and cobalt. The total contents of calcium and selenium in red cabbage leaves from inside (14-16 leaf) were highest. Results showed that the red-purple hue is more pronounced outside of the red cabbage than inside and it was also found that there are losses of yellowish hues for white cabbage from the outer leaves to the inner ones. Regarding the content of anthocyanins, it was obtained a value of 65.124 mg/100 g fresh weigh for outer leaves of red cabbage. Our results indicated that ascorbic acid content of red cabbage is approximately 3 times higher than in the white cabbage.

Open access
Some quality parameters of mustards from the Romanian market

Abstract

Five commercial mustards, made by different manufacturers, were studied to examine their physico-chemical properties and to establish relationships between those properties. Physico-chemical analysis revealed distinct differences between the mustards in the dry matter and extract contents and smaller differences in the protein, fat and ash levels. Two of the investigated mustards did not satisfy the requirements of the relevant Romanian standard regarding dry matter content. Statistical analysis of the results showed significant linear correlations between the dry matter, fat, protein and ash contents of mustards and some parameters of rheological model.

Open access
Evaluation of the antioxidant activity of some types of red and white wines

Abstract

Samples of commercially available Romanian wines were analyzed in order to determine total phenols content and the antioxidant activity. The content of total phenolics in the extracts was determined according to the Folin-Ciocalteu method and calculated as gallic acid equivalents (mg GAE/100g). Antiradical activities of the extracts were evaluated by a micro assay using 1, 1¢-diphenyl-2-picrylhydrazyl spectrophotometric method. Wine characteristics measurements were examined by multivariate data analysis, using principal component analysis (PCA). Total polyphenol content was correlated to the antioxidant activity of the studied wine samples. The values of the inhibition power of free radical, PI%, are ranging between 1.68 for white wine and 0.95 for red wine (“Bull blood” bottled by Tohani winery, Prahova, Romania).

Open access
Analytical characterization of some pasteurized apple juices during storage

Abstract

The aim of the study was to assess the effect of three weeks of storage on the chemical and rheological properties of apple juices obtained from Idared and Jonatan apples variety. Total antioxidant activity, levels of bio-active compound groups and the viscosity were measured to characterize the investigated juices. The method applied for the determination of ascorbic acid concentration was with 2, 6-diclorophenolindophenol. Total phenols (TP) in apple juices were determined using the Folin-Ciocalteau method and antioxidant activity by the use of DPPH free radical method. The viscosity of apple juices was investigated by a rotational viscometer, Brookfield viscometer (Brookfield Engineering Inc., Model RV-DV I Prime) with RV spindles. During three weeks of storage, different rates of all measured properties have been observed decreasing for both studied apples varieties juices. The juices from Jonatan apples have higher antioxidant activities that are correlated with the higher content in polyphenols and lower values of viscosity.

Open access
Pollen morphology of Nothofagus (Nothofagaceae, Fagales) and its phylogenetic significance

Abstract

Nothofagaceae (southern beeches) are a relatively small flowering plant family of trees confined to the Southern Hemisphere. The fossil record of the family is abundant and it has been widely used as a test case for the classic hypothesis that Antarctica, Patagonia, Australia and New Zealand were once joined together. Although the phylogenetic relationships in Nothofagus appear to be well supported, the evolution of some pollen morphological traits remains elusive, largely because of the lack of ultrastructural analyses. Here we describe the pollen morphology of all extant South American species of Nothofagus, using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and light microscopy (LM), and reconstruct ancestral character states using a well-supported phylogenetic tree of the family. Our results indicate that the main differences between pollen of subgenera Fuscospora (pollen type fusca a) and Nothofagus (pollen type fusca b) are related to the size of microspines (distinguishable or not in optical section), and the thickening of colpi margins (thickened inwards, or thickened both inwards and outwards). In particular, Nothofagus alessandrii, the only extant South American species of subgenus Fuscospora, presents distinctive pollen features that have not been observed in any other species of the genus (i.e. a large granular infratectum and spongy apertural endexine). Species of subgenus Lophozonia are characterized by having the largest pollen grains, with polygonal outline in polar view, microspines distinguishable in optical section, long and non-thickened colpi, and a thin endexine. The reconstruction of character states for the node corresponding to the common ancestor to genus Nothofagus leads us to conclude that the ancestral form of Nothofagaceae should have had: equatorial diameter < 40 μm, circular outline in polar view, microspines distinguishable in optical section, short colpi thickened inwards, and a thin endexine. These features are fully consistent with those present in Nothofagidites senectus Dettmann & Playford, the oldest fossil species of Nothofagaceae recorded in Campanian-Maastrichtian sediments of Gondwana.

Open access