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Open access

Vita Šterna, Sanita Zute and Zaiga Vicupe

Abstract

Consumption of dietary fibre has potential in improving nutrition and health. For further breeding of oats, it is necessary to increase knowledge on variation in the content of fibre and bioactive components in oats. Therefore, the aim of the present investigation was to study the extent of variation in β-glucan concentration of oats grown in Latvia and to evaluate association of β-glucan concentration with protein and fat concentration in newly created oat breeding lines. In 2015 and 2016, concentration of protein, fat, and β-glucan in grain of hulled oat varieties ‘Laima’, ‘Peppi’, and ten breeding lines was determined. The obtained results showed a wide range of fat concentration among varieties, with a range from 5.9 to 8.3%. The concentration of β-glucan ranged from 1.8 to 3.6% depending on the year. The β-glucan concentration had medium close positive correlation with lipid and weak significant positive correlation with protein concentration, which significantly differed among genotypes.

Open access

Ilze Beitāne, Gita Krūmiņa-Zemture, Zanda Krūma and Ingmārs Cinkmanis

Abstract

The objective of the current study was to analyse the total phenolic concentration (TPC), total flavonoid concentration (TFC), individual phenolic compound concentration and DPPH′ radical scavenging activity of four buckwheat (raw, roasted, white and dark) flour samples obtained from the Latvian market, in comparison to those of wheat flour, which is the most common ingredient in production of cereal products. TPC, TFC, and DPPH′ radical scavenging activity values were determined using spectrophotometric methods. Phenolic compounds were determined based on the high performance liquid chromatographic method (HPLC). All buckwheat flour samples had significantly higher TPC and TFC than wheat flour. The highest TPC (974.74 mg GAE·100 g−1 DW) and TFC (495.31 mg CE·100 g−1 DW) was found in raw buckwheat flour (p < 0.05). Buckwheat flour samples demonstrated similar DPPH′ radical scavenging activity, which ranged from 21.067 to 22.644 mM TE·100 g−1 dry matter, and was significantly higher (p < 0.05) than in wheat flour (0.731 mM TE·100 g−1 of dry matter). Dark buckwheat flour contained the highest level of rutin (4.613 mg·100 g−1), whereas raw buckwheat flour displayed the highest level of 3.5-dihydroxybenzoic acid (6.356 mg·100 g−1), sinapic acid (0.947 mg·100 g−1) and epicatechin (2.608 mg·100 g−1).

Open access

Ida Jākobsone, Sanita Zute, Māra Bleidere, Ināra Kantāne and Vadims Bartkevičs

Abstract

The aim of the study was to determine concentrations of 13 macro and trace elements in different barley genotypes depending on the year of growth (2011, 2012, and 2013) and agricultural practice (conventional/organic). Cd, Pb, Cr, Ni, and Al concentrations were determined by electrothermal atomic absorption spectrometry and K, Na, Zn, Cu, Ca, Mg, Mn, and Fe concentrations by flame atomic absorption spectrometry. Statistically different concentrations of Cr, Cu, and Zn occurred among genotypes; for Ca, Mn, and Fe concentrations between barley grains, grown conventionally and organically; for Cr and Ni concentrations between hulled and hull-less grain and for Cd, Cr, Ni, Cu, Zn, Al, K, and Na concentrations among the study years. Concentrations of potentially hazardous elements were low (Cd < 0.005–0.027, Pb 0.013–0.066, Cr 0.111–0.327, Ni 0.161–1.264, Cu 2.8–4.7 and Al 1.62–6.09 mg·kg−1). Barley products can provide necessary macro and trace elements, especially of Mn, Mg, Fe, and Zn (7.8–16.1; 1024–1249; 29.2–52.9, and 20.5–33.7 mg·kg−1, respectively).

Open access

Māra Kūka, Ilze Čakste and Pēteris Kūka

Abstract

Oxidation of fats and oils reduces the nutritional value of food and causes various health problems. The addition of antioxidants prevents the oxidation of fats in the food. The antioxidant activity of antioxidants represents the ability to inhibit the process of oxidation. The antioxidant activity of herbal extracts has usually been assessed in a linoleic acid emulsion system. The aim of the present study was to evaluate inhibition of conjugated diene formation in Latvian linseed oil. Ethanol extract of the calyx of Hibiscus sabdariffa L., vanillin, α-tocopherol and 2,6-di-tert-butyl-4-methylphenol as additives were compared for their antioxidative activity. The samples of linseed oil with additives were incubated for 24 h at 60 °C and then analysed using UV spectrophotometry (λ = 234 nm). The antioxidant activity of additives was characterised by the percentage of formation of conjugated dienes. The ability of additives to inhibit oxidation in linseed oil decreases as follows: vanillin, 2,6-di-tert-butyl-4-methylphenol and α-tocopherol. Our results indicate that linseed oil can be used to test antioxidative activity of substances.

Open access

Līga Prieciņa and Daina Kārkliņa

Abstract

Carrot (Daucus carota L.) is a globally used vegetable from the Apiacea family. It contains macro and micro elements, as well as various phytochemicals. The aim of the study was to determine concentration of carotenoids and organic acids, phenolic composition and antiradical scavenging activity, and colour changes during steam-blanching (for 1.5 and 3.0 min) and in dried carrots in convective and microwave-vacuum driers. Gravimetric, spectrophotometric, and high performance liquid chromatography (HPLC) methods were used for analysis. Carotenoids in fresh carrots were detected in high amounts, which decreased during thermal treatment and drying. The main organic acids in fresh carrots detected in highest amounts were oxalic, tartaric, quinic, malonic, and citric acids. Ascorbic acid concentration decreased minimally with steam processing, but significantly during drying. Fresh carrots contain minimal amounts of total phenolics, which increased during the thermal and drying processes used, while flavonoid, flavonol, flavan-3-ol and phenolic acid concentration decreased. The compound found in highest amounts by HPLC methods were 3.4-dihydroxybenzoic and 3.5-dihydroxybenzoic acids, catechin, 4-hydroxybenzoic acid, epicatechin and sinapic acid.

Open access

Liene Ozola and Solvita Kampuse

Abstract

The objective of this study was to examine the suitability of heat treatment methods on concentrations of bioactive compounds in pumpkin–guelder rose sauce. Berry hybrids 2--30--K, 2--45--K and variety ‘Krasnaya Grozdj’ were selected for further research. The juice of these fruits was used to create pumpkin–guelder rose sauce samples (experimental samples) where the pumpkin puree and guelder rose fruit juice ratio was 74.5 : 13.1. To all samples heat treatment under atmospheric conditions (traditional cooking) and vacuum cooking at 0.6 bar pressure at 85 °C and 0.2 bar pressure at 75 °C temperature was performed. These samples were compared with uncooked experimental samples. Sauce chemical evaluation showed better retention of vitamin C concentrations (per dry weight) for guelder rose variety ‘Krasnaya Grozdj’ sauces cooked at 0.2 bar pressure, compared to fresh samples. Samples that were prepared with vacuum cooking methods on average showed higher total phenol concentration, antiradical activity and total anthocyanins concentration than in control samples cooked under atmospheric conditions. These observations were consistent with reports in the literature on better preservation of bioactive compounds in plant-based products that are cooked under vacuum heat treatment at lower temperatures.

Open access

Imanta Ozola-Zālīte, Anda Vīksna, Jeļena Ivanova, Agnese Ūdre and Aldis Puķītis

Abstract

Severe acute pancreatitis occurs in 15–25% of all patients with acute pancreatitis (AP), and has a dismal prognosis. Recognition of severe AP risk factors could provide identification and resuscitation of patients with impending severe course of disease. Our study aim was to analyse body composition, measured by computed tomography (CT) scans, in acute pancreatitis patients and its impact on disease severity. The study was a prospective cohort study carried out in the period from January 2015 – April 2016. In total 100 patients underwent CT imaging. Body constitution was analysed by CT examinations using the ImageJ v1.49q standard software. The third lumbar vertebra was selected as the landmark measurement. Muscular, visceral, subcutaneous, and intramuscular adipose tissue area were measured. Values were normalised for stature to obtain lumbar skeletal muscle and adipose tissue indexes (cm2/m2). Acute pancreatitis severity was determined by Atlanta revised criteria (2012). Among the included patients, moderately severe AP occurred in 83% (83 patients) cases, and severe AP in 17% (17 patients). 38% of the patients had normal weight according to BMI, 33% were overweight 33%, and 28% were obese. Sarcopenia was detected in 51%. Sarcopenia was found in six patients (35%) with severe AP and in 45 patients (54%) with moderately severe AP. General linear model analysis showed that obesity (p value = 0.026) and increased intramuscular fat area (p value = 0.029) had effect on severe AP. In conclusion, body composition analysis showed that adiposity is a risk factor for severe AP, and higher intramuscular fat area seemed to be another risk factor for severe AP.

Open access

Marika Liepa, Jelena Zagorska, Ruta Galoburda and Svetlana Kostascuka

Abstract

High pressure processing (HPP) is an alternative to traditional thermal treatment and can be used in the dairy industry for increasing the microbiological safety of milk and for preserving its biologically active substances. HPP effectiveness in providing microbiological quality of product is still under discussion; thus, the aim of the study was to evaluate the effect of HPP technology on microbiological quality of skimmed milk. Raw, pasteurised (78 °C, 15–20 s), HPP treated (250 MPa, 15 min; 400 MPa, 3 min; 400 MPa, 15 min; 550 MPa, 3 min) and skimmed milk, processed by combining pasteurisation and HPP were analysed and compared. The total plate count (LVS ISO 4833-1:2013) and presence of coliforms (LVS EN ISO 16654:2002) were determined in analysed skimmed milk samples. Significant decrease (p < 0.05) of colony forming units (CFU) was observed in samples processed by combining two treatment types: pasteurisation and HPP. The minimum treatment parameters for shelf-life extension of skimmed milk were determined: pressure not less than 400 MPa and holding time at least 15 minutes.

Open access

Gunta Leite and Daiga Kunkulberga

Abstract

Scientific studies have regularly confirmed that nowadays the salt consumption through food is too much, and its consumption has to be reduced. The aim of the study was to ascertain the amount of salt consumed per day by 18–35 year-old Latvians as well as to identify the main sources of salt in their diets. The following research methods were used in the study: questionnaire based on an example recommended by the World Health Organisation, sociological research method, bread baking tests, and logically constructive, and statistical research methods. The results of this research showed that the average intake of salt in the diet of 18–35 year-old Latvians was 7.1 g per day. Of all the respondents, 63% consumed more than the recommended 5 g of salt per day, and none of them consumed less than necessary to meet their physiological needs. The results showed that women consumed less salt than men — approximately 6 g per day, while men consumed 8.2 g of salt per day. The main sources of salt in the diet of 18–35 year old Latvians were cereals and cereal products, as well as meat and meat products. Among cereal products, the key source of salt was represented by bread and pastry.