The characterization of four types of Indian honeys (Trifolium alexandrinum (berseem clover), Brassica sp. (mustard), Helianthus annuus (sunflower), Eucalyptus lanceolatus) was carried out on the basis of their quality parameters (moisture, pH, free acidity, reducing sugars, sucrose, fructose/glucose ratio, colour, ash content, proline content, invertase activity, diastase activity, hydroxymethylfurfural (HMF), and mineral content (sodium, potassium, iron, calcium, zinc, and copper). The source of honey had a significant (P<0.05) effect on moisture content, free acidity, pH, reducing sugar content, fructose/glucose ratio, hydroxymethylfurfural content, invertase and diastase activities, sucrose content, proline, ash content, and mineral content. Pattern recognition methods, such as principal component analysis and linear discriminate analysis, were performed to classify honey on the basis of physicochemical properties and mineral content. The variables calcium, pH, and potassium exhibited higher discrimination power.
Authors:J. Tarek-Tilistyák, J. Agócs, M. Lukács, M. Dobró-Tóth, M. Juhász-Román, Z. Dinya, J. Jekő and E. Máthé
The nutritive value, the microbiological safety of oilseed cake (OSC) obtained from naked pumpkin seed (PuC), sunflower seed (SC), yellow linseed (LC), and walnut (WnC), and their impact on wheat flour (WF) dough and bread sensory characteristics at 5% and 10% addition ratio were investigated. The OSCs had high protein (34–50%), fat (8–15%), total dietary fibre (23–36%) content and high energy value (383–444 kcal/100 g)). The OSC samples with a minimal exception fulfilled the requirements of feed legislation in force. An increased water absorption, dough development time, and reduced elasticity were observed probably due to the enhanced fiber and protein content. Dough stability increased with WnC, and decreased with PuC or SC addition. Enrichment provided the appearance of a brown bread for WnC, of a half-brown bread for LC. PuC gave an unusual look. The appearance of OSC fortified bread similar to daily bread, was an advantage resulting the 1st rank for 10% WnC bread and the 2nd one for 10% LC bread (P=0.05). The studied OSCs are suitable for food enrichment, however, in case of PuC and SC fortified flour blends, hydrocolloid application is recommended. Our data suggest that the newly developed fortified breads could be a valuable source for healthy nutrition.
Authors:J. Tarek-Tilistyák, M. Juhász-Román, J. Jekő and E. Máthé
We evaluated the microbiological safety, the short-term storability, and the macronutrients of oil seed cake (OSC) obtained from walnut (WnC), linseed (LC), and sunflower seed with hull (SC). The OSCs had 3.6–5.8% moisture content, 0.50–0.60 water activity (aw), 29.9–39.4% protein, 15.5–23.6% fat, and 36.6–48.0% dietary fibre content. The grinded OSCs could be stored in opaque plastic bags for 4 months at temperatures of 4 °C, 14 °C, and 25 °C. Total colony count of mesophilic microorganisms depending on oxygen demand and spore-forming ability, and faecal indicator microorganisms were determined during a 4-month storage term at 4 °C, 14 °C, and 25 °C using traditional culturing methods. The OSCs were free from sulphite-reducing Clostridia and coliforms, including Escherichia coli. Data were analyzed statistically by multifactor analysis of variance. Ascending order of the average contamination of the three products (log10 CFU g−1) was aerobic sporogenic bacteria (2.39), fungal count (2.51), total aerobic microbe count (3.00), anerobic sporogenic bacteria (3.75), and total anaerobic microbe count (4.23). As for the average microbial count, WnC was the least (2.73 log10 CFU g−1) and LC was the highest (3.53 log10 CFU g−1) contaminated material. Regarding the variation of microbial contamination during storage, temperature was indifferent (P=0.191), while storage time (P=0.0033) and the product type were influential (P=0.000).
Authors:K. Albert, A. Koris, I. Gáspár, G. Rácz and Gy. Vatai
Membrane emulsification (ME) is a relatively new technique for the highly controlled production of particulates, which helps to obtain a narrower distribution compared to other emulsification techniques such as homogenizers or ultrasound. Benefits of membrane emulsification for food applications include the low shear properties and the uniform size distribution. In this process, the dispersed phase (oil) is pressed through the pores of a microporous membrane directly into the continuous phase (water) flowing tangentially to the membrane surface. The purpose of the emulsification experimentations was to find and model operating conditions of the operation. In laboratory experiments from conventional, commercial grade sunflower oil (dispersed phase) and from distilled water (solid phase), emulsions were prepared. The ceramic tube membrane with nominal pore size of 1.4 μm was used in the experiments (ZrO2). In order to increase the shear-stress near the membrane wall (influence the characteristics of the flow regime of the continuous phase), a kind of self-fabricated helical-shaped-ribbon reducer was installed inside the tube membrane.
Authors:J. Belovai, R. Romvári, H. Fébel, M. Mézes, D. Bánáti and A. Szabó
Replacement of animal fat with plant oils is a very popular research field, due to the increasing prevalence of cardiovascular diseases in association with saturated fatty acid consumption. The aim of this study was to reduce amount of pig backfat in a meat product (Párizsi) and to partially replace it with soybean- (SBL) or sunflower lecithin (SFL). Between the samples difference was realized in fatty acid (FA) profile, mostly in total n6 FA content. The replacement also altered the colour compared to the control. The oxidative stability (MDA) analysis showed that SBL was more prone towards preparation technology (10 nmol MDA/g) than the Sfl(9 nmol MDA/g). The lecithin appeared as foreign taste based on the sensory test. The aromatic difference, as assessed with electronic nose, was clearly detectable between Sfland SBL. The increasing supplementation levels were also properly distinguished with discriminant analysis within the SBL and Sflseries. Summarized, Sflwas found to be a better antioxidant, but SBL improved the FA profile into a more favourable state. The lecithin-replacement made unlikeness in the taste compared to the control.
Authors:K. Szentmihályi, A. Blázovics, I. Kocsis, Edit Fehér, B. Lakatos and Péter Vinkler
The metabolic alteration of fatty liver causes significant changes in the composition of bile fluid secreted by epithelial liver cells. These processes include both organic molecular and inorganic ion content changes in bile juice as well. In this work ion concentration differences of bile fluid in experimental hyperlipidemic rats compared to normal ones were monitored. Fatty liver in young male Wistar albino rats was induced by 2% cholesterol, 20% sunflower oil and 0.5% cholic acid added to the normal food and 3% alcoholic water was administered to rats for 9 days. The development of hyperlipidemy was detected by measuring serum parameters and fatty liver was proved by morphological investigations. The ion concentrations of bile fluid samples were determined by ICP-OES (inductively coupled plasma optical emission spectrometry). The bile fluid samples were digested with a mixture of HNO3 and H2 O2 . The results show that the concentration of calcium and phosphorus in bile juice increased significantly in hyperlipidemic rats compared to the control. Significant concentration changes have also been detected for chromium and manganese. The changes in metal ion metabolism also point to the damage of liver cells owing to metal complex evacuation.
., Hadolin, M., Knez, Ž. & Bauman, D. (2000): Comparison of antioxidative and synergistic effects of rosemary extract with α-tocopherol, ascorbyl palmitate and citric acid in sunflower oil. Fd Chem., 71 , 229-233.
): Antioxidant activity of extracts and essential oils from Turkish spices on sunflower oil. Acta Alimentaria , 24 , 81-90.
Antioxidant activity of extracts and essential oils from Turkish spices on sunflower oil
Fleming, S.E., Sosulski, F.W., Kilara, A. & Humbert, E.S.
(1974): Viscosity and water absorption characteristics of slurries of sunflower and soybean flours, concentrates and isolates.
J. Fd Sci.