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Abstract

Camelina sativa is well known due to high content of polyunsaturated fatty acids in its oil. Till now this oil has been studied mainly for applications as raw material for synthesis of resins, biodiesel and hydrocarbon fuels. This study examines the oxidative stability of cold-pressed Camelina sativa (also known as camelina, false flax or gold-of-pleasure) oil and its extracts of spices. Despite the high content of polyunsaturated fatty acids, Camelina sativa oil appeared more rigid against oxidation than rapeseed or flax oil. Extracts of different spices were prepared by maceration in camelina oil at room temperature for 24 h. The stability of extracts was determined under accelerated oxidation conditions and monitored by peroxide values. Most of the tested additives (e.g., bay leaves, allspice, clove, barley sprouts, coriander, ginger) did not influence or even decreased oxidative stability of the oil. However, oil with thyme additive demonstrated remarkably higher stability then Camelina sativa oil alone. Press-cakes of camelina seeds were extracted with two polar solvents (ethanol or water) and their mixtures under variable conditions (room temperature or reflux). Prepared polar extracts of press-cakes were characterised by total polyphenol content (Folin–Ciocalteu method) and antiradical activity against 1,1-diphenyl-2-picryl hydrazyl and galvinoxyl.

Abstract

Differences in biochemical composition in dehulled and pearled grain samples affected by the various degrees of pearling were studied for spring barley (Hordeum vulgare L.). Twelve covered spring barley and two hulless genotypes were examined. Commercial samples of pearled barley were included for comparison. Covered barley grain samples were pearled using a small-scale barley pearler to obtain dehulled and pearled barley grain products with pearling percentage of 12% and 30%, respectively. Significant differences were observed in the chemical composition between dehulled grain and pearled grain. As the outer layers of the covered grain were removed to a greater degree by pearling, crude protein content, crude ash, total phenolic concentration and radical scavenging activity in the pearled grain significantly decreased (p < 0.001), while starch concentration increased, without changes in the β-glucans concentration. The concentration of phenolic compounds in the dehulled barley grain samples were 1.30 to 1.61 times higher than for pearled grains. There was a significant (p < 0.01) correlation determined among values of dehulled and pearled grain of different barley genotypes in crude protein, starch, and β-glucan content, but no relationship was found in total phenolic content and radical scavenging activity.

Abstract

It is very important to promote public awareness of the negative effects on health — trans fatty acid effects on cardiovascular disease. The study included 70 patients of the Latvian Centre of Cardiology, Pauls Stradiņš Clinical University Hospital (PSCUH). The PSCUH research institute gave permission to conduct the study. The patients answered questions about their awareness of trans fatty acids. The questionnaire used was obtained from the study “Use of Trans Fat Information on Food Labels and Its Determinants in a Multiethnic College Student Population” and modified for survey of the cardiology unit patients. The majority (74%) of the respondents had heard and read something about trans fatty acids, but 62% women and 54% men were poorly informed about trans fatty acids and their negative effect on cardiovascular diseases. Unclear issues for patients were discussed after the questionnaire.

Abstract

The main purpose of the study was to determine changes of polyphenol concentrations in hybrids of Nante type carrots during storage. Fresh Nante type ‘Forto’ variety carrots and carrot hybrids ‘Bolero’ F1, ‘Champion’ F1, and ‘Maestro’ F1 were cultivated in the Zemgale region of Latvia. Carrots were stored for six months in air (+3 ± 1 °C, RH = 89 ± 1%) and polyphenol compound concentrations were determined at two month intervals. High-performance liquid chromatography was used to determine concentrations of eight polyphenols in carrots: gallic acid, catechin, epicatechin, caffeic acid, chlorogenic acid, ferulic acid, vanillin, and rutin. Significant differences occurred in polyphenol concentrations of fresh Nante type variety ‘Forto’ carrots and several hybrids (‘Bolero’ F1, ‘Champion’ F1, and ‘Maestro’ F1) during storage. After six months of storage, the concentration of polyphenol compounds of Nante type carrots decreased — caffeic acid by 64.6%, chlorogenic acid — by 37.9% and vanillin — by 81.5%. However, during storage, concentration of some polyphenol compounds increased, as catechin by 30.5%, epicatechin by 85.2%, gallic acid by 48.5% and ferulic acid by 87.9%.

Abstract

The aim of this study is to assess body fat level, energy and nutrient intake of adolescent ballet dancers and to compare these results with those of adolescents from ordinary school. Participants included 39 ballet dancers and 70 adolescents from ordinary school. Body composition was measured using a multi-frequency 8-polar bioelectrical impedance leg-to-hand analyser (X-Scan Plus II, Korea). Dietary intakes were assessed using a three-day estimated food record. Nutritional intake was calculated using the Nutri Survey software. Ballet dancers were slightly shorter, lighter, with less fat and fat-free mass compared to girls from ordinary school. 51.3% (95% CI 35.59 to 66.97) of ballet dancers and 4% (95% CI; 0.27 to 11.15) of ordinary school girls had a body fat level of 12% or less. The recommended amount of 35–45 kcal energy to kg fat-free mass for aesthetic sports was not reached by 42.1% (95% CI 27.61 to 50.65%) of ballet dancers. No statistically significant difference was found in percent body fat between ballet dancers who consumed energy less than the recommended amount compared to those who ate normally, but fatfree mass (p < 0.05) was lower in those who consumed 35–45 kcal energy to kg fat-free mass or less compared to those who ate more. The investigated groups had an inadequate intake of minerals and vitamins during the winter period.

Abstract

Concentration of trace and major elements is an important indicator of nutritional value of food, also regarding cultivated food crops like fruits, berries, and vegetables. Concentration of elements differs regionally and is influenced by various factors. Nevertheless, some chemical elements (As, Cd, Hg, Ni, Pb, Zn, etc.) are known as environmental pollutants and may affect the quality and safety of crops and food products. The aim of the study was to determine the concentration of potentially toxic elements like Cd, Cr, Cu, Fe, Ni, Pb, and Zn in samples of berries grown in allotment gardens of Rīga city. Dried and homogenised samples of raspberries, strawberries, red currants, black currants, gooseberries, and cherries were mineralised in a solution of concentrated HNO3/H2O2 by heating on a thermoblock. Quantitative analysis of sample solutions was performed using atomic absorption spectroscopy. Potentially toxic elements were in concentrations as follows: Fe > Zn > Cu > Ni > Pb > Cr > Cd. Mean concentrations of the elements of the major concern were: Ni 0.54 mg/kg, Pb 0.20 mg/kg, Cr 0.10 mg/kg, and Cd 0.03 mg/kg. Results indicated significant variability of element concentration among the species.

Abstract

Fennel (Foeniculum vulgare L.) is an aromatic plant belonging to Apiaceae family widely cultivated elsewhere for its strongly flavoured leaves and seeds. Fennel seeds are of particular interest as a rich source of both vegetable and essential oils with high amounts of valuable components. However, residual cakes after oil extraction were typically considered as byproducts, in the present framework, the potential added value of these cakes was studied. The aim of this study was to investigate the effect of addition of fennel cake and seeds to protein bread quality. In the current research, a single-screw extruder, which is a solvent-free technique, was used for fennel seed oil extraction. For the protein bread making, fennel seed and cake flour in concentrations from 1 to 6% were used. Moisture, colour L*a*b*, hardness, total phenolic concentration, DPPH radical scavenging activity, and nutritional value of protein bread were determined. The addition of fennel cake and seeds had significant (p < 0.05) effect on bread crumb colour and hardness attribute, whereby the bread became darker and harder in texture than the control. Moreover, higher antioxidant activity and total phenolic concentration were observed for both protein breads enriched with fennel cake and seed flour. The overall results showed that addition of fennel cake and seed had beneficial effects on phenolic concentration, antioxidant activity and quality of protein bread. This result suggests also that added value of fennel seeds oil by-products could be increased by their utilisation in bread production.

Abstract

Daily intake of cereal fibre reduces incidence and progression of metabolic diseases. Very little is known on how triticale (Triticosecale) influences human health and its role in regulating carbohydrate metabolism. The aim of the study was to investigate glycaemic and insulin response in blood after consuming whole grain triticale cereal flakes. A group of twelve healthy, young people, aged from 18 to 30 years participated in the test. The participants in fasted state were given equivalent carbohydrate amounts of triticale cereal and reference food (glucose solution). Postprandial blood glucose and plasma insulin concentrations were measured according to Brouns et al. (2005). Whole grain triticale cereal flakes elicited lower metabolic responses compared to glucose solution. Intake of the triticale cereal flakes induced significantly lower incremental insulin area (iAUC 0–120 min) 1672.9 ± 619.85 than glucose solution 2646.65 ± 1260.56 and showed lower insulinemic indices (II) 68 ± 19.0 (p < 0.05). A low insulin incremental peak was associated with less severe late post-prandial hypoglycaemia. Our study showed that triticale cereal product caused low acute insulinemic response and improved glycaemic profiles, similarly to the rye products studied before. The results also suggested that the triticale cereal flakes could have beneficial appetite regulating properties. Thus, triticale flakes would be a wonderful option for functional breakfast cereal mixtures that might influence course of metabolic syndrome prevention

Abstract

Oxidation and microbial spoilage have a negative effect on the quality of meat and meat products, causing changes in their sensory and nutritional properties. Herbs contain biologically active compounds, like phenols with antioxidative and antimicrobial properties. Phenols can be used as substitutes for commercial antioxidants to prevent lipid oxidation, thus maintaining the colour and flavour of the product. The aim of the study was to investigate the the potential use of herbal extracts in ethanol/water application for the maintenance of pork meat quality during storage. Four herbs growing in Latvia — nettle (Urtica dioica L.), lovage (Levisticum officinale L.), oregano (Origanum vulgare), and horseradish (Armoracia rusticana L.) were chosen for the study. An optimal ethanol concentration for the extraction of the phenolic compounds was obtained with ethanol 50%/water 50% concentration (v/v). Prepared herbal extracts were added to chilled pork to determine the quality of the pork during storage. Changes in meat quality and its sensory properties for chilled pork without extracts appeared on day 18 of storage. Negative changes in sensory properties of meat samples with nettle extract were observed on day 22 of storage, and with lovage, oregano, and horseradish extracts on day 32. Statistically significant differences (p ≤ 0.05) were observed for microbiological indices between pork samples with herbal extracts and the control sample.

Abstract

In this study the efficiency of horseradish Amorica rusticana leaf, and Levisticum officinale lovage leaf and stem extracts for the stabilisation of rapeseed oil during storage was evaluated. Plant extracts were added to unrefined rapeseed oil in a concentration of 1% by weight, which was chosen based on the results of previous experiments studying the possibilities of the addition of different concentrations of plant extracts for extending the shelf life of the oil. As a control a rapeseed oil sample without extracts was analysed, and for comparison butylated hydroxytoluene (BHT) in the maximum allowed concentration was added to the oil. The efficiency of the extracts in oil was tested in the dark and in the light/dark cycles (day/night regime). For all samples the peroxide value, acid value and DPPH scavenging activity were determined. The oil samples with the added plant extracts stored in the dark oxidised significantly (p < 0.05) slower than the control sample and the sample with BHT. After 24 weeks of storage, the lowest peroxide value was in the sample with the lovage stem extract. The extracts contain compounds that could absorb light (for example chlorophyll) and in the light/dark conditions accelerate oxidation in oil. Among the analysed extracts the lovage stem extract was the most effective oil oxidation inhibitor, but horseradish leaf extract was the most effective DPPH radical scavenger.