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The present study was undertaken to assess the effects of gamma irradiation (0, 2, 4, and 6 kGy) on microbial, chemical, and sensory values of Jabaly Syrian goat meat during storage at 4 °C for 1, 3, 4, and 5 weeks. Irradiation was effective in reducing the microbial load and increasing the shelf-life of goat meat. The radiation doses required to reduce the microorganisms by 90 percent (D10) in goat meat were 294 and 400 Gy for Salmonella and E. coli, respectively. The main fatty acids identified from the goat meat were oleic, stearic, and palmitic acids. No significant differences were observed in moisture, crude protein, crude fat, ash, pH value, fatty acids, total acidity, volatile basic nitrogen, and sensory properties (texture, flavour, colour, and taste) of irradiated and non-irradiated goat meat. Lipid peroxidation measured in terms of thiobarbituric acid-reactive substances (TBARS) increased on irradiation and chilled storage. Sensory evaluation showed no significant differences between irradiated and non-irradiated goat meat.
Palm fat is one of the most commonly used fats in food industry. The main role of palm fat is to develop the desired texture of food products. Fat blends were developed to find the most appropriate mixture fitting the technological needs. In our work palm mid fraction (PMF) was mixed with anhydrous milk fat (AMF), goose fat (G), and lard (L) in a 1:1 ratio. Anhydrous milk fat represents fat consisting of a wide range of fatty acids. Goose fat is a soft, easily melting fat, and lard is characterized as animal fat with wide melting temperature interval. The measurements aimed to establish the miscibility of the fats and the effect of animal fats on the melting-solidification profile of palm mid fraction. SFC vs temperature curves, Differential Scanning Calorimetry (DSC) melting thermograms describe the melting profile of the samples. Isotherm crystallization by SFC vs time curves and DSC cooling thermograms were measured to characterize the solidification of pure fats and the blends. Since the SFC curves did not show crosspoints we concluded that fats blended in a 1:1 ratio were miscible. Anhydrous milk fat strongly modified the properties of palm mid fraction, the blend became similar to anhydrous milk fat. Goose fat had no strong modification effect on palm mid fraction and could be considered as a softening agent. The effect of lard was complex: melting and solidification behaviour of the blend differed from the characteristics of both parent fats.
Power ultrasound has vast potential in the food industry; however, there are no works on its effects on desserts. Thus, the objectives of this study were to investigate the effect of ultrasound as a mixing or homogenization step or as a tool to modify the texture of the soy-based desserts without reformulating the product. Different properties of soybased desserts were evaluated and the behaviour of the samples during storage under refrigeration (60 days) was monitored. The samples were treated with an ultrasound probe for 1, 3, and 5 min. The treated samples showed lower mean particle size, lower consistency index, higher flow index, and clear difference in their microstructure. However, water holding capacity and particle size dispersion index values did not differ among untreated and treated soy based desserts for 1 and 3 minutes, and none of the treatments caused visible colour differences among the samples. Periodically, rheological properties, pH, soluble solids content, colour, particle size, and water holding capacity were determined. After 60 days, all evaluated properties differed significantly, except for the pH.
The present study investigated how sighted and blind sensory assessors evaluated the quality of various apple varieties: Regal Prince (Gala Must), Jonagold Schneica (Jonica), Watson Jonathan, Golden Reinders and Generos. A total of 80 sighted and 12 blind people participated in the study, in three groups (sighted people without blindfolds, sighted people with blindfolds, blind people). The preference of sensory attributes (size, shape, colour, texture, taste and odour) was evaluated on a six-category scale. The data were analysed using single-factor (ANOVA, LSD95%, 99%) and multi-factor (Cluster analysis, ANOVA, LSD95%, 99%) evaluation. The results showed that blind and sighted assessors made similar judgements on external attributes perceptible by touch (size, shape), but differed in their evaluation of certain quality factors (flavour, taste), resulting in opponent patterns of preference on some apple varieties (Generos, Jonagold Schneica). A further conclusion of the experiment is that there was less deviation between the judgements of sighted assessors when they saw the apples than when they were blindfolded. The background of this phenomenon might be explained by the uncertainty and disturbed perception, which lead to inconsistent judgements.
Increasing the protein and antioxidant content of food products is a constant challenge amongst researchers. Dried pasta products are popular amongst all groups of society. The most important factor in pasta processing is the quality of the flour. Millet (Panicum miliaceum) flour has high nutritional value, enriching it with cricket (Gryllus bimaculatus) flour is good choice to increase the quality of protein composition and antioxidant properties of products. Flour mixtures of millet and insect flours (5% and 10%) were analysed after mixing and pasta processing. Addition of wheat gluten improved both texture and nutrition value of pasta products. Total polyphenol content, antioxidant capacity, total protein content, free and total amino acid composition were studied. Quality analysis of dried pasta products were carried out according to Hungarian standards. Data was analysed with Kruskal-Wallis test, Dunn's pair-wise post hoc test was used with Bonferroni correction. The correlation was determined by Spearman's rank. Addition of cricket flour modified the pH, acid value, moisture content, and colour of the samples, these changes lasted during storage. Enrichment could increase the total phenol content significantly even at the low level of 10%. Heat treatment during pasta processing had negative effect on the antioxidant capacity except at higher cricket flour contents. Cricket flour's high protein content proportionately increased millet flour's, thus pasta products'. Dried pasta products passed all quality norms. Enrichment of millet flour with cricket flour is favourable from both nutritional and quality aspects.
The acoustic response method is one of the most important dynamic methods used for assessment of the mechanical texture of different fruits and vegetables. The method is based on the mechanical excitation of the sample and the assessment of its resonant frequency. Different approaches are known for the interpretation of the vibration behavior of the samples having definite shapes. According to the most widely used interpretation, the stiffness of the sample ( s ) is dependent on the resonant frequency ( f ) and the mass ( m ) of the sample. The aim was to extend the acoustic response method to typically non-spherical samples (carrot, cucumber, etc.) to find a correct interpretation of the behavior of the sample and to introduce a stiffness coefficient suitable for characterization of the mechanical properties of a long shaped sample. According to Finite Element Modeling and experimental tests on carrot samples a close correlation was found between the resonant frequency and the effective length of the sample in a given shape range. A principally new stiffness coefficient was proposed for long shaped samples. It was found to be suitable for the characterization of the hardness of the vegetables in a wide size range.
Beecher, B., Bowman, J., Martin, J.M., Bettge, A.D., Morris, C.F., Blake, T.K., Giroux, M.J. 2002. Hordoindolines are associated with a major endosperm-texture QTL in barley (Hordeum vulgare) . Genome 45 :584
-chain gelatin . Biopolymers , 14 ( 10 ), 1995 – 2005 . F OEGEDING , E.A. ( 2007 ): Rheology and sensory texture of biopolymer gels . Curr. Op. Colloid In. , 12 ( 4–5 ), 242
Koncepcióváltás a belvízgazdálkodásban: talajtani és vízminőségi kérdések
Conceptual Change in Excess Water Management: Soil and Water Quality Issues
Munkánk során igyekeztünk a belvízminőséggel, annak időbeli változásaival kapcsolatos kérdéseket megválaszolni.
Az eddig vizsgált nehéz agyag talajtextúrájú algyői mintaterületről származó eredmények rávilágítanak arra, hogy tápanyagok tekintetében számottevő terhelés érheti az elvezetés során a belvizet befogadó felszíni víztestet különösen a belvízelöntés kezdeti időszakában. A terhelést kiemelten a lebegőanyaghoz kötött tápanyagformák adják, míg emellett a felszíni vízborítás kialakulását követő első napokban és hetekben jelentős, környezetvédelmi határértéket is átlépő mineralizált nitrogéntartalomra is kell számítani.
A belvizes környezet reduktív jellemzőinek erősödésével a nitrát – külső utánpótlás nélkül – hamar átalakul, míg a hőmérséklet és a biológiai aktivitás emelkedésével a lebegőanyagtartalom koagulációja és flokkulációja is jelentősen csökkenti a tápanyagterhelést.
Ezen a mintaterületen képződött belvíz öntözővízként való hasznosítását az öntözőrendszer eltömődéséhez vezető magas lebegőanyagtartalom, illetve esetenként magas vas- és mangántartalom nehezítheti jellemzően szintén a tavaszi időszakban, amikor pl. kelesztő öntözéshez használhatjuk fel a vizet a magasabb térszíneken.
Általános érvényű következtetések levonásához a kutatás későbbi szakaszában két új, eltérő talajtani és hidrológiai adottságú mintaterületre is kiterjesztjük vizsgálatunkat. A helyszíni mérésekkel párhuzamosan összeállítunk egy laboratóriumi kísérletet kiemelten a talajtényező hatásának megfigyeléséhez. Ez lehetőséget fog nyújtani arra is, hogy a tápanyagformák időbeli átalakulásáról is pontosabb képet kapjunk.
Colour, texture, pectin autolysis, membrane permeability and microstructure (SEM, TEM), β-galactosidase and polygalacturonase were studied in apricots (cv. Magyar kajszi) harvested in mature green, straw yellow, bright orange and deep orange stages. The L* increased from mature green to straw yellow then decreased from straw yellow to deep orange state. The a* values increased with ripening. The bright and deep orange apricots were significantly softer than the mature green and straw yellow ones and the membrane permeability increased with ripening. The presence of β-galactosidase enzyme was proved by immunoblotting analysis using monoclonal anti-β-galactosidase clone GAL-13 (Sigma) in all ripening stages. The enzyme activity was very low in mature green stage and increased significantly (P>95%) with increasing ripeness and during storage. The PG activity was very low in the mature green apricot. A significant (P>95%) increase was observed in the straw yellow apricot and in the riper fruits. The mature green apricot showed a regular, the straw yellow and bright orange samples showed a moderately regular tissue structure, while the tissue of the deep orange apricot collapsed (SEM). The cell wall and the middle lamella of the green apricot (TEM) were intact. Generally, there were intact cytoplasm membranes with some damaged parts. In the straw yellow apricot, the cell wall started to loosen, the middle lamella lost pectic polysaccharides. The structure of the cytoplasm was not recognisable, the tonoplast and the cytoplasm membrane were injured. The cell wall of the bright orange apricot was similar to that of the straw yellow ones. The middle lamella dissolved and hairy, fibrillar structure of cell wall was found in the deep orange samples.
