Boja dijetetskih čokolada tokom skladištenja do godinu dana

In this work color quality characteristics of the upper surfaces of commercial dietary chocolates of different manufacturers were investigated. Color was determined instrumentally, using the three stimulus colorimeter "MINOLTA" Chroma meter CR 400. Results were expressed in CIE, CIELab and Hünter systems, immediately after the production (0 - 30 days and after 90, 180, 270 and 360 days of keeping in storage at the temperature of 15°C. Whitening Index (WI) was also calculated. On the basis of the obtained results, it could be concluded that all the analyzed samples of dietary chocolates had approximately the same color characteristics qualities (lightness, nuance and color saturation), having only negligible variations, during keeping and storage at 15°C for up to 1 year.U ovom radu su ispitane karakteristike kvaliteta boje gornje površine komercijalnih dijetetskih čokolada, različitih proizvođača. Boja je određena instrumentalno, na fotoelektričnom tristimulusnom kolorimetru "MINOLTA", Chroma meter, CR 400. Rezultati su izraženi u CIE, CIE Lab i Hünter-ovom sistemu i to odmah nakon proizvodnje (0-30 dana), posle 90, 180, 270 i 360 dana čuvanja i skladištenja, pri temperaturi do 15°C. Izračunata je vrednost indeksa beline (WI). Na osnovu dobijenih rezultata možemo zakjlučiti da su svi analizirani uzorci dijetetskih čokolada približno istih karakteristika kvaliteta boje (svetloća, nijansa, zasićenost), uz blaga, neznatna odstupanja, a tokom čuvanja i skladištenja na temperaturi do 15°C do godinu dana

The effects of nitrogen nutrition and glutenin composition on the gluten quality in wheat genotypes

The effect of nitrogen nutrition treatments on the gluten content and some quality parameters of eight winter wheat cultivars has been studied. Six different nitrogen rates were applied (0, 60, 90, 120, 150 and 180 kg N ha-1) to wheat cultivars chosen according to the structure of their high molecular weight glutenin subunits (HMW-GS) at the Glu-D1 locus. Four genotypes with HMW-GS 2 + 12 and another four with HMW-GS 5 + 10 were used in the study. The analysis of gluten quality involved the wet gluten content and rheological properties determined by the sensory and instrumental methods (“Instron 4301”). It was determined that in all the cultivars the wet gluten content increased significantly (P < 0.05) in parallel with N rate increase. The cultivars reacted differently regarding their wet gluten rheological properties. Libellula, a cultivar with poor bread making quality (HMW-GS 2 + 12), did not react to different N rates. Sremica, a cultivar with excellent bread making quality (HMW-GS 5 + 10), reduced its gluten quality as the N rate increased. The values obtained by the instrumental method “Instron 4301” at 90% wet gluten compression varied widely (from 0.002 to 0.041 kN). The increase of N fertilizer rate was significantly positively correlated (r2 = 0.811) with the wet gluten content and strength in the cultivars with HMW-GS 5+10

Uticaj azotne ishrane i gluteninske strukture na kvalitet glutena pšenice

The effect of nitrogen nutrition treatments on the gluten content and some quality parameters of eight winter wheat cultivars has been studied. Six different nitrogen rates were applied (0, 60, 90, 120, 150 and 180 kg N ha-1) to wheat cultivars chosen according to the structure of their high molecular weight glutenin subunits (HMW-GS) at the Glu-D1 locus. Four genotypes with HMW-GS 2 + 12 and another four with HMW-GS 5 + 10 were used in the study. The analysis of gluten quality involved the wet gluten content and rheological properties determined by the sensory and instrumental methods ('Instron 4301'). It was determined that in all the cultivars the wet gluten content increased significantly (P lt 0.05) in parallel with N rate increase. The cultivars reacted differently regarding their wet gluten rheological properties. Libellula, a cultivar with poor bread making quality (HMW-GS 2 + 12), did not react to different N rates. Sremica, a cultivar with excellent bread making quality (HMW-GS 5 + 10), reduced its gluten quality as the N rate increased. The values obtained by the instrumental method 'Instron 4301' at 90% wet gluten compression varied widely (from 0.002 to 0.041 kN). The increase of N fertilizer rate was significantly positively correlated (r2 = 0.811) with the wet gluten content and strength in the cultivars with HMW-GS 5+10.Ispitivan je uticaj azotne ishrane na sadržaj i kvalitativna svojstva glutena osam sorti ozime pšenice. Primenjene doze azota su bile: 0, 60, 90, 120, 150 i 180 kg N ha-1. Sorte su odabrane u skladu sa strukturom njihovih visokomolekularnih gluteninskih subjedinica (HMW-GS) na Glu-D1 lokusu. Odabrane su četiri sorte sa HMW-GS 2+12 i četiri sorte sa HMW-GS 5+10. Analize su obuhvatale sadržaj i reološka svojstva glutena određena senzornom i instrumntalnom ('Instron 4301') metodom. Utvrđeno je da se paralelno, sa povećavanjem nivoa N-ishrane značajno (P lt 0.05), povećavao i sadržaj vlažnog glutena kod svih sorti. Sorte su različito reagovale u pogledu njihovih reoloških svojastava. Sorta Libelula, sa slabim pekarskim kvalitetom i strukturom (HMW-GS 2+12), nije reagovala na različite doze azota. Kod sorte Sremica, odličnog pekarskog kvaliteta i strukturom (HMW-GS 5+10), sa povećavanjem doza azota pogoršana su reoloških svojstava glutena. Rezultati dobijeni instrumentalnom 'Instron 4301' metodom, pri (90%) kompresiji vlažnog glutena varirali su od (0,002 do 0,041 kN). Povećavanje primenjenih doza azota bilo je u značajnoj pozitivnoj korelaciji (r2 = 0.811) sa sadržajem i jačinom glutena kod sorti sa HMW-GS 5+10 strukturom

Termo-mehanička i senzorna svojstva pšeničnog i ražanog hleba pripremljenih sa različitim koncentracijama aditiva

The effects of different concentrations of complex additive containing emulsifiers, oxido-reductive substances and enzymes, on the rheological conditions of dough and sensory properties of three groups of bread were investigated. The dough obtained from mixed wheat and rye flours had the best initial quality and the lowest degree of protein network weakening. The best expected baking properties were shown by the white wheat flour due to the least damage of its starch. The use of the additive had an effect on the absorption of water and on the majority of S-values of all sorts of flour. The amount of additive had a significant effect on the sensory properties of wheat bread crumb texture. Also, storage duration significantly affected (p lt 0.01) the sensory properties of integral wheat bread aroma-taste and the weighted mean score. The interaction of these two factors had no significant effect on any of sensory properties of the investigated groups of bread.Primenom klasičnih reoloških metoda moguće je ispitati kvalitet brašna i njegovu pogodnost za specifične namene, uglavnom na bazi osobina proteina i skorba. Upotrebom savremenih uređaja simuliraju se procesi koji se odvijaju tokom proizvodnje hleba i dobija se niz informacija o fizičkim parametrima testa (apsorpcija vode, razvoj i stabilnost testa, mehanička i termička razgradnja proteinske mreže), stanju skroba u testu (nivo želatinizacije, amilolitička aktivnost, stabilnost pri kuvanju) uz značajno skraćen postupka ispitivanja. U ovom radu, ispitivani su efekti različitih koncentracija kombinovanog aditiva na reološka svojstva testa i senzorne osobine tri grupe hleba. Najbolji početni kvalitet i najniži stepen slabljenja proteinske mreže je uočen kod testa dobijenog iz mešavine pšeničnog i ražanog brašna. Najbolja očekivana pecivna svojstva imalo je belo pšenično brašno, zbog najmanjeg oštećenja skroba. Upotreba aditiva uticala je na apsorpciju vode i na većinu C-vrednosti svih vrsta brašna. Koncentracija aditiva imala je značajan uticaj na senzorno svojstvo teksture, tj, mrvljivost pšeničnog hleba. Vreme skladištenja je veoma značajno (p lt 0,01) uticalo na senzorna svojstava arome tj. ukusa integralnog pšeničnog hleba i statistički značajno na ponderisanu srednju vrednost ocene ovog hleba. Interakcija ova dva faktora nema statistički značajan uticaj na bilo koje od senzornih svojstava ispitivanih grupa hleba

Factors influencing students' choice of fast food restaurants

The global expansion of fast food consumption habits and the consequent change in the competitive environment led to greater market research and the targeting of consumer groups. On the other hand, the growth of the market and the increase in the number of fast food restaurants have encouraged consumers to pay more attention to the products they consume, that is, have influenced their interest in the diversity of factors that are decisive when choosing a restaurant. This study investigates factors influencing students' choice of fast food restaurants. The study was conducted at University of Novi Sad. The results show that the most important influences on this choice are Food Quality, Nearness and Accessibility and Hygienic factors, primarily cleanliness of the restaurant, kitchen, and service personnel. Differences in fast food choice factors were found regarding the gender of respondents

Investigations of Bread Production with Postponed Staling Applying Instrumental Measurements of Bread Crumb Color

Crumb color quality characteristics of bread of different compositions (whole grain, rye, barley and diet bread) at 24 hours intervals during three days after bread preparation were investigated by means of a MOM-color 100 tristimulus photo colorimeter, in CIE, CIELab, ANLAB and Hunter systems. The highest value of average reflectance y (%) was found for barley bread (immediately after preparation), so that can be said that this sample was “conditionally” the lightest. The lowest values of y (%) were found for diet bread, so that it can be considered as the “conditionally” the darkest product. Colors of all investigated bread samples were lighter after three days of keeping compared to day 0. Changes of average reflectance of bread samples packed in polyethylene packaging with keeping time can be described by linear equation (correlation coefficient 0.99). The dominant wavelength of barley and diet bread confirm the presence of yellow pigment. Color qualities of the mentioned kinds of bread depend on processes during bread staling and raw material composition of bread (flour). Color quality measurements can be used as easy auxiliary method for screening in the development of slower staling bread

Udjeli ukupnih fenola, flavan-3-ola i proantocijanidina te oksidacijska stabilnost i antioksidacijski kapacitet čokolade tijekom skladištenja

Antioxidant (AO) capacity of chocolates with 27, 44 and 75 % cocoa was assessed after production and during twelve months of storage by direct current (DC) polarographic assay, based on the decrease of anodic current caused by the formation of hydroxo-perhydroxyl mercury(II) complex (HPMC) in alkaline solutions of hydrogen peroxide at potentials of mercury oxidation, and two spectrophotometric assays. Relative antioxidant capacity index (RACI) was calculated by taking the average value of the AO assay (the sample mass in all assays was identical). Oxidative stability of chocolate fat was determined by differential scanning calorimetry. Measured parameters and RACI were correlated mutually and with the content of total phenols (Folin-Ciocalteu assay), flavan-3-ols (vanillin and p-dimethylaminocinnamaldehyde assay) and proanthocyanidins (modified Bate-Smith assay). During storage, the studied functional and health-related characteristics remained unchanged. Amongst applied AO assays, the DC polarographic one, whose validity was confirmed by two-way ANOVA and F-test, correlated most significantly with oxidative stability (oxidation onset temperature and induction time). In addition, principal component analysis was applied to characterise chocolate types.Antioksidacijski kapacitet čokolade s 27, 44 i 75 % kakaa ispitan je odmah nakon proizvodnje te tijekom dvanaest mjeseci skladištenja, i topolarografskom metodom praćenja smanjenja anodne struje uslijed nastajanja kompleksa žive(II) s hidroksilnim i perhidroksilnim radikalima u alkalnim otopinama vodikovog peroksida pri elektrodnom potencijalu žive, te dvjema spektrofometrijskim metodama. Relativni antioksidacijski kapacitet čokolade izračunat je iz prosječnih rezultata dobivenih pojedinom metodom. Oksidacijska je stabilnost masti u čokoladi određena diferencijalnom pretražnom kalorimetrijom. Dobiveni rezultati uspoređeni su s ukupnim udjelom fenola (određenim pomoću metode Folin-Ciocalteu), flavan-3-ola (određenim pomoću vanilina i p-dimetilaminocinamaldehida) i proantocijanidina (određenim pomoću modificirane Bate-Smith metode). Funkcionalna svojstva i antioksidacijski kapacitet čokolade nisu se mijenjali tijekom skladištenja. Rezultati dobiveni polarografskom metodom uz pomoć jednosmjerne struje, obrađeni dvosmjernim ANOVA testom i F-testom, pokazali su najveću korelaciju s oksidacijskom stabilnosti, tj.temperaturom na kojoj započinje oksidacija i indukcijskim vremenom oksidacije. Analizom glavnih komponenata okarakterizirani su svi uzorci čokolade

Meat quality characteristics of DurocxYorkshire, DurocxYorkshirexwild boar and wild boar

Chemical composition, pH value, fatty acids profile, cholesterol content, color and sensory analysis of pork meat from Duroc x Yorkshire (D x Y), Duroc x Yorkshire x wild boar (D x Y x WB) crossbreeds and wild boars (WB) was investigated. Samples for all tests were taken from m. longissimus dorsi. Chemical composition and pH value were tested by ISO methods. Fatty acid and cholesterol determination was performed by gas chromatography technique with external standard method. Color was determined instrumentally using the thristimulus colourimeter. The overall sensoric quality (appearance, texture and smell) of samples of raw meat was evaluated. In evaluation of results the scoring system was used. In chemical composition (moisture, fat, protein, ash) and pH values statistically significant difference was noted (p<0,05) between each of the examined groups. Also, among all the examined groups statistically significant difference (p<0,05) was found for fatty acids and cholesterol content. Measurment of the color of meat from all three groups showed that the L*, a * b *, Chroma and Hue angle were also statistically significantly different (p<0,01)

Sensory Properties and Color Measurements of Dietary Chocolates with Different Compositions During Storage for Up to 360 Days

In this work sensory characteristics (appearance – color, brilliance, shape and surface; texture – structure, break, firmness and chewiness; aroma – odor and taste) of dietary chocolates of different compositions were evaluated, in parallel with color parameter measurements. Color was determined instrumentally on the top and bottom surfaces, using a “MINOLTA” Chroma meter CR 400 thristimulus colorimeter. Sensory evaluation was performed by a group of experienced panelists immediately after the production (0 – 30 days), and then after 90, 180, 270 and 360 days of storage under ambient conditions (t = 18 – 20°C). Results were statistically analyzed by the two-factorial analysis of variance (MANOVA) and with the LSD – test. It was concluded that the storage time up to one year had statistically highly significant (p < 0.01) effects on the sensory attributes of chocolate, as well as on instrumentally measured color parameters

Initial results of the colorimetric indices of the oldest exposed pedocomplex (Titel loess plateau, Serbia)

In this study we present an in-depth description of the colorimetric values for the lowest section of the Dukatar Loess Palaeosol Sequence (LPS) pedocomplex S5. Formed during the Marine Isotope Stage (MIS) 13-15, it represents the oldest pedocomplex exposed at the base of the Titel loess plateau (TLP), near the confluence of the Tisa and Danube rivers in Vojvodina (northern Serbia). The results of low-field magnetic susceptibility measurements (χlf) were compared to colour properties (obtained by conventional methods as well as instrumental measuring) and quantified Soil Development Indices (SDI). Of these measurements we found that the Redness Index (RI1) yielded the most useful results, as this index appears most sensitive to lithological changes and soil development intensity. It was also observed that a high level of correlation existed between χlf, and a* chromaticity. The initial results of this study highlight the utility of colorimetric methods as an interdisciplinary tool when evaluating the presence of ferromagnetics, and the application of rock magnetism to the Middle and Upper Pleistocene LPS of the Middle Danube Basin. The presented approach can be used to observe the evolution of climatic and ecological conditions in the given study area, and for establishing correlations between sites extending over the Eurasian LPS provinces