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

Senzorna, antioksidativna i reološka svojstva različitih vrsta čokolada sa probioticima

Food products containing beneficial microorganisms, mostly lactic acid bacteria which effectively affect human health, represent one of the largest market of functional foods, with dairy products as the most accessible ones. Tendency that useful probiotic bacteria safer and easier survive the conditions of the gastrointestinal tract, and the need to make them available over a longer period of time compared to durability of dairy products, imposed the idea to conduct the extensive testing of probiotics in chocolate as a carrier. Research program in the scope of this dissertation was aimed at investigating the possibility of application of probiotics in different types of chocolate, because of their sensitivity to a large number of process factors and environmental conditions, and bearing in mind that sustainability is an essential property that determines their effectiveness. By including of probiotic cultures in the chocolate composition, an additional dispersed phase is introduced, which can influence the microstructure and cause a change in appearance - colour, texture, melting and rheological properties of the product. In addition, some studies suggest the possibility of an interaction between probiotic microorganisms and polyphenol components in food containing them, which may lead to a change of its antioxidant capacity. In order to establish the extent to which the incorporation of probiotics affect the dominant characteristics of different types of chocolate, an examination of their sensory, antioxidant and rheological properties was carried out immediately after production (0-30 days) and during storage of 90, ie 180 days. With the aim of determination of all factors that may affect the functionality of chocolate with probiotics, the analysis of used packaging materials, which included testing of physical-mechanical and barrier properties, were also conducted. In particular, the freeze-dried probiotic strains Lactobacillus acidophilus NCFM® and Bifidobacterium lactis HN019, as well as DUOLAC MIX L3 - microencapsulated mixture of three probiotic cultures: Lactobacillus acidophilus, Streptococcus thermophilus and Bifidobacterium breve, were added into chocolates of different composition (milk, dark with 44% and dark with 75% cocoa solids)...Prehrambeni proizvodi koji sadrže probiotske mikroorganizme, uglavnom bakterije mlečne kiseline, sa pozitivnim učincima po zdravlje, predstavljaju jedno od najvećih tržišta funkcionalne hrane, među kojima su proizvodi od mleka najdostupniji. Težnja da korisne, probiotske bakterije bezbednije i lakše prežive uslove gastrointestinalnog trakta, kao i potreba da budu dostupne tokom dužeg vremenskog perioda u odnosu na onaj koji je ograničen trajnošću proizvoda od mleka, nametnula je ideju da se obave opsežnija ispitivanja primene probiotika na čokoladi kao nosaču. Program istraživanja u okviru ove doktorske disertacije bio je usmeren na ispitivanje mogućnosti primene probiotika u različite vrste čokolada, zbog njihove osetljivosti prema velikom broju procesnih faktora i uslovima okoline, a imajući u vidu da je održivost esencijalno svojstvo koje uslovljava njihovu efikasnost. Inkluzijom probiotskih kultura uvodi se dodatna disperzna faza u sastav čokolada, što može imati uticaja na njihovu mikrostrukturu i usloviti promene izgleda - boje, teskture, topivosti i reoloških svojstava. Pored navedenog, pojedina istraživanja ukazuju na mogućnost postojanja interakcija između probiotskih mikroorganizama i polifenolnih komponenata namirnice u koje su dodati, što može dovesti do promene njenog antioksidativnog kapaciteta. Kako bi se ustanovilo u kojoj meri je inkorporiranje probiotika uticalo na dominantna svojstva različitih vrsta čokolada, obavljeno je ispitivanje njihovih senzornih, antioksidativnih i reoloških karakteristika neposredno nakon proizvodnje (0-30 dana) i tokom skladištenja od 90, odnosno 180 dana. Radi utvrđivanja svih faktora koji mogu uticati na funcionalnost čokolada sa probioticima obavljene su i analize upotrebljenih ambalažnih materijala, koje su obuhvatale ispitivanje fizičkomehaničkih i barijernih svojstava..

Sensory, antioxidant and rheological properties of different types of chocolates with probiotics

Prehrambeni proizvodi koji sadrže probiotske mikroorganizme, uglavnom bakterije mlečne kiseline, sa pozitivnim učincima po zdravlje, predstavljaju jedno od najvećih tržišta funkcionalne hrane, među kojima su proizvodi od mleka najdostupniji. Težnja da korisne, probiotske bakterije bezbednije i lakše prežive uslove gastrointestinalnog trakta, kao i potreba da budu dostupne tokom dužeg vremenskog perioda u odnosu na onaj koji je ograničen trajnošću proizvoda od mleka, nametnula je ideju da se obave opsežnija ispitivanja primene probiotika na čokoladi kao nosaču. Program istraživanja u okviru ove doktorske disertacije bio je usmeren na ispitivanje mogućnosti primene probiotika u različite vrste čokolada, zbog njihove osetljivosti prema velikom broju procesnih faktora i uslovima okoline, a imajući u vidu da je održivost esencijalno svojstvo koje uslovljava njihovu efikasnost. Inkluzijom probiotskih kultura uvodi se dodatna disperzna faza u sastav čokolada, što može imati uticaja na njihovu mikrostrukturu i usloviti promene izgleda - boje, teskture, topivosti i reoloških svojstava. Pored navedenog, pojedina istraživanja ukazuju na mogućnost postojanja interakcija između probiotskih mikroorganizama i polifenolnih komponenata namirnice u koje su dodati, što može dovesti do promene njenog antioksidativnog kapaciteta. Kako bi se ustanovilo u kojoj meri je inkorporiranje probiotika uticalo na dominantna svojstva različitih vrsta čokolada, obavljeno je ispitivanje njihovih senzornih, antioksidativnih i reoloških karakteristika neposredno nakon proizvodnje (0-30 dana) i tokom skladištenja od 90, odnosno 180 dana. Radi utvrđivanja svih faktora koji mogu uticati na funcionalnost čokolada sa probioticima obavljene su i analize upotrebljenih ambalažnih materijala, koje su obuhvatale ispitivanje fizičkomehaničkih i barijernih svojstava...Food products containing beneficial microorganisms, mostly lactic acid bacteria which effectively affect human health, represent one of the largest market of functional foods, with dairy products as the most accessible ones. Tendency that useful probiotic bacteria safer and easier survive the conditions of the gastrointestinal tract, and the need to make them available over a longer period of time compared to durability of dairy products, imposed the idea to conduct the extensive testing of probiotics in chocolate as a carrier. Research program in the scope of this dissertation was aimed at investigating the possibility of application of probiotics in different types of chocolate, because of their sensitivity to a large number of process factors and environmental conditions, and bearing in mind that sustainability is an essential property that determines their effectiveness. By including of probiotic cultures in the chocolate composition, an additional dispersed phase is introduced, which can influence the microstructure and cause a change in appearance - colour, texture, melting and rheological properties of the product. In addition, some studies suggest the possibility of an interaction between probiotic microorganisms and polyphenol components in food containing them, which may lead to a change of its antioxidant capacity. In order to establish the extent to which the incorporation of probiotics affect the dominant characteristics of different types of chocolate, an examination of their sensory, antioxidant and rheological properties was carried out immediately after production (0-30 days) and during storage of 90, ie 180 days. With the aim of determination of all factors that may affect the functionality of chocolate with probiotics, the analysis of used packaging materials, which included testing of physical-mechanical and barrier properties, were also conducted. In particular, the freeze-dried probiotic strains Lactobacillus acidophilus NCFM® and Bifidobacterium lactis HN019, as well as DUOLAC MIX L3 - microencapsulated mixture of three probiotic cultures: Lactobacillus acidophilus, Streptococcus thermophilus and Bifidobacterium breve, were added into chocolates of different composition (milk, dark with 44% and dark with 75% cocoa solids)..

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

Ispitivanje kvaliteta kafe različitim metodama

The results obtained by the analysis of the samples of coffee mostly consumed on our market showed that the coffee quality corresponds to the values as given in the Law of Health Food. It was not found that any of the parameters which determine food quality exceeded permitted values. Content of heavy metals and aflatoxines is below permitted values. The least content of caffeine was determined in a coffee sample roasted in the private roaster’s shop, and only in it the presence of coffee surrogates/substitutes was not proved. The obtained results of the coffee analysis showed that the coffees of most popular producers are very equal, and results of caffeine analysis are even more equal. This indicates the most probable fact that coffee is of the same origin, and that later, on during production, a different mixture was made, which affects the final product and gives aroma and taste to the liquid.Dobijeni rezultati ispitivanja kvaliteta kafa koje se najčešće konzumiraju na našem tržištu pokazali su da kvalitet kafe odgovara vrednostima koje su preporučene Zakonom o zdravstvenoj ispravnosti namirnica. Ovim ispitivanjima utvrđeno je da nisu prekoračene dozvoljene granice nijednog od parametra koji utiču na kvalitet namirnica. Sadržaj teških metala i aflatoksina je ispod dozvoljenih vrednosti. Najmanji sadržaj kofeina određen je u uzorku kafe koja je proizvedena u privatnoj pržionici, a takodje jedino u njoj nije dokazano prisustvo surogata kafe. Dobijeni rezultati ispitivanja kafe ukazuju da su kafe najpoznatijih proizvođača veoma ujednačene, a rezultati ispitivanja kofeina čak i izjednačeni. To ukazuje na verovatnu činjenicu da je kafa istog porekla, a da je kasnije u pogonima pravljena različita mešavina, koja i utiče na konačni proizvod i koja daje aromu i ukus napitku

Contribution of Osmotically Dehydrated Wild Garlic on Biscuits' Quality Parameters

Wild garlic generally improves strengths and regenerates the body and also helps in the treatment of various diseases. In this study the contribution of wild garlic osmotic dehydration process in sugar beet molasses on biscuits' quality parameters is investigated. Presented results showed that addition of osmotically dehydrated wild garlic in molasses impoved textural characteristics of biscuits by lowering hardness and increasing fracturability and also changed colour characteristics of biscuits. Chemical composition of biscuits with added osmotically dehydrated wild garlic was improved in comparison to the biscuits with added fresh wild garlic, where proteins, total sugars, celulose and ash compositions were increased in amounts of 1.86, 3.2, 15.8 and 5.76 % respectively. Addition of osmodehydrated wild garlic had provided higher Zn, Cu and Fe biscuits' content in comparison to the addition of fresh wild garlic, in amounts of 2.75, 15.33 and 15.84 % respectively. Developed mathematical models of biscuits quality parameters were statistically significant, while predicted and observed responses corresponded very well. In effort of obtaining new types of products, new application of known ingredients was proposed, allowing incorporation of sugar beet molasses' rich nutrient content in wheat products formulation

Ispitivanje kvaliteta ulja dopremljenog kao 'Humanitarna pomoć'

The result of examination of oil of unknown origin from the crisis territory as follows: the examined oil has qualities permissible for human nutrition. The examination of contained quantity of contaminants and heavy metals showed that ingredients were not higher than values prescribed by the Statute, except for lead. It is on the upper limit. Contents of radionuclides range within the limits of average values. The quantity is not dangerous for human food. However, the present methods and the existing apparatus are not developed enough, so there is ignorance of the total structure of the sample. There is a possibility of substances being present in very low quantities, first of all, cancerogenic substances or substances which can provoke somatic or genetic changes. Paracelsius said: 'Everything is toxic, but it depends of dose'. That 'dose' is the main cause of consequences (therapeutic, toxic or lethal) which begin as a result of carrying contaminated substances into human organism.Ispitivanje ulja nepoznatog porekla sa kriznih područja pokazalo je da se radi o ulju kvaliteta dozvoljenog za ljudsku ishranu. Ispitivanja sadržaja kontaminatora i teških metala pokazalo je da primese nisu vise od dopuštenih i zakonom determinisanih vrednosti, osim olova koje se nalazi na samoj gornjoj granici. Sadržaj radionuklida nalazi se u granicama prosečnih vrednosti i ne predstavlja opasnost za ljude pri konzumiranju ulja. Ono što upućuje na oprez je da sadašnje metode i postojeća aparatura nisu dovoljno razvijene pa ostaje nepoznanica o supstancama koje se nalaze u veoma niskim koncentracijama - u prvom redu kancerogenih agenasa ili supstanci koje izazivaju somatske ili genetske promene. Ali, kao što je rekao još Paracelzijus 'sve je otrovno samo zavisi od doze', ta 'doza' je glavni uzrok posledica (terapeutskim, toksičnim ili letalnim) koje nastaju kao rezultat konzumiranja kontaminiranih supstanci

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

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

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