Promena sadržaja antocijana pri ceđenju maline

Change in anthocyanins content under different conditions of extraction enzymatic maceration and heat treatment of two raspberry cultivars (Villamette and Meeker) was determined. Experiments were carried out on a laboratory hydraulic extractor. During extraction commercial operating conditions were emulated using a "Bucher" extractor (pressure 180-200 bar 1-3 pulp shakings). A pectin preparation Klerzyme®120, manufactured by DSM France, was used for maceration and depectinization, because it is specific for "sour fruits" with pH below 3.2. At a single-stage maceration, it was applied in the amount of 200-400 g/t, for 1-2 hours at 50°C. In a two-stage maceration and depectinization, the enzyme was added as follows: in the first stage 100-200 g/t for 0.5 - 1 hour at 20°C and in the second stage 4-8 g/hl for 1-2 hours at 200°C. Thermal breaks of raspberry pulp were performed at raised temperatures for 2 and 5 min in order to examine the effects of raised temperatures on anthocyanins extraction. The application of heat-enzymatic treatments of the pulp prior to extraction proved to be suitable in both raspberry cultivars. Apart from well-known degrading effects of heat on anthocyanins, the juice obtained by extraction, after enzymatic maceration, has higher anthocyanins content by 30% than the juice obtained without enzymatic maceration. Juice pasteurization, in each stage of processing, produced markedly negative effect on anthocyanins content therefore their content decreases considerably. The forms of anthocyanins that are lost most are those uncolored. In batches subjected to a two -stage enzymatic maceration, despite initial high anthocyanins content, the content of total anthocyanins is reduced after the second pasteurization to the approximate value as that in batches subjected to a single-stage enzymatic maceration.U radu je određivana promena sadržaja antocijana pri različitim uslovima cedjenja, enzimiranja i toplotnog tretiranja dve sorte maline (vilamet i miker). Pri cedjenju su imitirani industrijski radni uslovi sa "Bucher", cednice (pritisak 180-200 bar, 1-3 rastresanja kljuka). Za maceraciju i depektinizaciju korišćen je pektinski preparat KlerzymeÒ120, proizvodjača DSM - Francuska, koji je specifičan za "kiselo voće" sa pH ispod 3,2. Pri maceraciji u jednom stepenu primenjen je u količini od 200 - 400 g/t, u toku 1 do 2 sata na 50oC. Pri dvostepenoj maceraciji i depektinizaciji, dodavan je enzim: u prvoj fazi 100 - 200 g/t u toku 0,5 do 1 sata na 20°C, a u drugoj fazi dodavan je 4 - 8 g/hl u toku 1 do 2 sata na 20°C. Blanširanja kljuka maline su izvedena na povišenim temperaturama u trajanju od 2 i 5 minuta radi ispitivanja uticaja povišenih temperatura na ekstrakciju antocijana. Primena odgovarajućeg toplotno-enzimskog tretmana kljuka pre ceđenja, kod obe sorte maline, se pokazala prihvatljivom. Sok dobijen ceđenjem, posle enzimiranja, sadrži oko 30% više antocijana u odnosu na sok dobijen bez enzimiranja. Kod serija sa dvostepenim enzimiranjem, i pored velikog početnog sadržaja antocijana, posle druge pasterizacije dolazi do smanjenja na približnu vrednost sadržaja ukupnih antocijana kao kod serija sa jednostepenim enzimiranjem. Pasterizacija soka, u svakoj fazi prerade dala je izrazito negativan efekat na količinu antocijana, tako da se njihov sadržaj znatno smanjuje. Najviše se gube neobojene forme antocijana

Primena ultrafiltracije za bistrenje soka jabuke

Raw depectinized apple juice was clarified in a laboratory scale ultrafiltration (UF) system using ceramic tubular membranes (Tech-Sep Carbosep) with a molecular weight cut-off of 300,000, 50,000, and 30,000 daltons. The experiments have been carried out over a wide range of transmembrane pressures (100-400 kPa), temperatures (293-328 K), and feed flow rates (100-900 mL/min). Permeate flux significantly decreased with time until a steady state was established. The steady-state permeate flux reached a maximum at a transmembrane pressure of about 200 kPa. Higher permeate flux was obtained at higher temperatures due to lower permeate viscosity. A linear relationship between steady-state permeate flux and feed flow rate in logarithmic coordinates was obtained and the slope of these lines ranged from 0.22 to 0.31.Bistrenje depektinizovanog matičnog soka jabuke uspešno je vršeno ultrafiltracijom kroz keramičke cevne membrane proizvedene od cirkonijum-oksida i titan-dioksida na podlozi od poroznog ugljenika. Eksperimenti su vršeni uz potpunu recirkulaciju retentata i sa protocima napojne struje u modulu od 100-900 ml/min. Fluks permeata u početku opada sa vremenom, ali se posle određenog vremena uspostavlja stacionarno stanje. Stacionami fluks permeata, L dostiže maksimum pri transmembranskom pritisku od oko 200 kPa, nakon čega opada sa daljim porastom pritiska. To se može objasniti deformacijom čestica mutnoće u sloju gela, raskidanjem krupnijih lančastih agregata otvorene strukture i formiranjem sitnijih čestica koje se gušće pakuju u sloju gela, što dovodi do smanjenja poroznosti i propustljivosti sloja. U log-log koordinatnom sistemu stacionami fluks permeata linearno raste sa porastom protoka napojnog soka, pri čemu nagib ovih pravih varira od 0,22 do 0,31

Konzervisanje malina liofilizacijom

Due to high water content (about 90%), specific total fruit texture characteristic light color and aroma, up to now raspberry has not been preserved via classical drying. The paper aimed to study the change in quality induced by liophilization as compared to convectively dried and fresh fruit. Cv Willamette was used for the trial. The chemical analyses involved the assessment of the following: the content of soluble solids total acids, total sugar, pH value, L-ascorbic acid, total anthocyanins total aroma, porosity of dried fruits, and organoleptic value. Liophilization was done in Edwards device at fruit temperature of -30°C. The pressure in the chamber accounted for 13 Pa, desorption temperature being 40°C. Convective drying was done in laboratory apparatus, entry air temperature being 65°C and relative humidity 6%. Dried fruits were rehydrated with water at room temperature. In compliance to the results obtained, it may be inferred that the stated method is highly suitable for sensitive fruit drying, such as raspberry. The analyses proved that the quality of convectively dried fruits as compared to liophilizated, is significantly poorer. Preservation of l-ascorbic acid (for about 54%) better maintenance of anthocyanins (for about 51%), reduced loss of total aroma (for about 66%) and reduction volume (for about 92%), higher porosity (for about 49%) and finally better organoleptic value (for about 51%) are the advantages of the method in question.Malina, sorta Vilamet je sušena postupkom liofilizacije i klasično, toplim vazduhom niske relativne vlažnosti. Ispitivane su promene u hemijskom sastavu, ukupnoj aromi, organoleptičnim svojstvima, gustini i zapremini, kod osušenih plodova u odnosu na sveže. Dobijeni rezultati pokazuju da se liofilizacijom može uspešno očuvati hemijski sastav, zapremina, aroma i boja maline

Degradacija boje maline pri enzimiranju i ceđenju

Pectin preparation Klerzyme®120, manufactured by DSM-France, specific for 'acid fruits' with pH below 3.2, was used for maceration and depectinzation. In terms of maceration at one degree, it was applied in the quantity of 200-400 g/t for 1 to 2 hours at 50°C. At the maceration at two degrees and depectinzation, the enzyme was added: In the first phase 100-200 g/t for 0.5 to 1 h at 20°C, and in the second, 4-8 g/hl for 1 to 2 hours at 20°C. Mush boiling was executed at increased temperatures for 2 and 5 minutes. The application of proper heat enzymatic treatment prior to squeezing proved to be acceptable. The juice obtained by squeezing upon the enzymatic treatment contains about 30% more anthocyanins as compared to juice produced without enzymatic treatment. In terms of the final content of anthocyanins, the same results were recorded with treatments. In each processing stage, juice pasteurization adversely affected anthocyanin levels.U radu je ispitivana promena sadržaja bojenih materija dve sorte maline Vilamet i Miker, pri različitim uslovima ceđenja, enzimiranja i toplotnog tretiranja. Ogledi su izvedeni na laboratorijskoj hidrauličnoj cednici, pri čemu su imitirani radni uslovi "Bucher" cednice (pritisak 180 - 200 bar, 1-3 rastresanja kljuka). Za maceraciju i depektinizaciju korišćen je pektinski preparat Klerzyme® 120 (DSM - Francuska), koji je specifičan za "kiselo voće" (pH ispod 3,2). Pri maceraciji u jednom stepenu enzim je dodavan u količini od 200 - 400 g/t, u toku 1 do 2 sata na 50°C. Pri dvostepenoj maceraciji i depektinizaciji, dodavan je enzim: u prvoj fazi 100 - 200 g/t u toku 0,5 do 1 sata na 20°C, a u drugoj fazi dodavan je 4 - 8 g/hl, u toku 1 do 2 sata na 20°C. Blanširanja kljuka maline su izvedena na povišenim temperaturama u trajanju od 2 i 5 minuta. Primena odgovarajućeg toplotno-enzimskog tretmana kljuka pre ceđenja pokazala se prihvatljivom. Pored poznatog degradacionog dejstva toplote na antocijane, sok dobijen ceđenjem, posle enzimiranja, sadrži oko 30% više antocijana u odnosu na sok dobijen bez enzimiranja. Pasterizacija soka, u svakoj fazi prerade, dala je izrazito negativan efekat na količinu antocijana. Najviše se gube neobojene forme antocijana. Kod serija sa dvostepenim enzimiranjem, i pored velikog početnog sadržaja antocijana, posle druge pasterizacije dolazi do smanjenja na približnu vrednost sadržaja ukupnih antocijana kao kod serija sa jednostepenim enzimiranjem

Microfiltration with periodic gas backwashing as an alternative technique for increasing permeate flux

In this paper, the influence of operating parameters (transmembrane pressure, temperature, the flow rate of retentate) on the cross - flow microfiltration of synthetic fruit juice and periodic backwashing with air was examined. In the experiments, the Kerasep W5 ceramic membrane with a separation limit of 0.2 mu m was used. The results of experiments in which different transmembrane pressures were used showed that stationary fluxes, at stationary conditions, after 60 minutes, have similar values. So, it can be concluded that the value of the driving force is irrelevant at steady state conditions. However, until the steady state conditions are established, a positive effect of the increase in the driving force is opposed to the negative effect of the increased polarization resistance, as a result of the driving force increase. Thus, the optimal transmembrane pressure was determined amounting to 2 bars. The optimum temperature of the process of clearing the fruit juices by microfiltration is reported as 55 degrees C. Higher temperatures are not used due to a degrading effect on the chemical composition of the juice and a long microfiltration process. With an increase in the temperature of retentate from 22 degrees C to 55 degrees C, the permeate flux increased up to 60 %. Increasing the flow rate of retentate reduces the thickness of the formed layer on the surface of the membrane. Due to limitations of the experimental setup and the large surface area of the membrane, the specific velocity of the retentate was low, so that the effects of cross-flow filtration were absent. The use of cross-flow filtration is one of the main requirements for increasing permeate flux, but in the present case it was in overall insufficient, so we have applied periodic air backwashing for improving fruit juice flux during membrane clarification. With this technique, the deposited layer on the membrane is lifted and the permeate flux is maintained at high levels preventing establishment of the steady state in the low flux zone. The time spent for the periodic backwashing was low as compared to the benefits of the increase in the collected permeate quantity. In all experiments with periodic backwashing with air, the collected permeate quantity is higher for up to 72.5 % as compared to experiments without backwashing. By increasing the backwashing duration, the flux increase is up to 5 %, which can be significant for microfiltration at industrial scale. Therefore, this technique is certainly recommended for microfiltration in the production of fruit juices

Kinetika fermentacije i fizičkohemijske karakteristike specijalnih piva sa dodatkom grožđa sorte Prokupac

Over the last decade, the market of special beers with improved healthy function and/or with new refreshing taste has significantly increased. One of the possible solutions enables mixing beer with bioactive components in grapes responsible for well-known health-promoting action of red wine. The effects of the addition of the Prokupac grape on the physicochemical properties and the fermentation kinetics of the grape beer were studied and the results were compared with a control lager beer. The effect of grape addition on the activity of yeast was also studied. Original extract, alcohol content, degree of fermentation, fermentation rate and yeast growth were significantly higher in beers with grapes as a consequence of higher concentration of simple sugars in grapes compared with pure wort. Based on the CIELab chromatic parameters the color of grape beer samples was yellow with certain proportion of redness, while the control beer was purely yellow. The increase in the concentration of grape mash affects the reduction of lightness and yellowness of beers, while the redness of samples was directly proportional with grape quantity. The phenolic content and antioxidant capacity of grape beers was remarkably higher compared to the control beer, which indicates that the grape beer is a better source of natural antioxidants than regular lager beer.Poslednjih godina, tržište specijalnih vrsta piva koja se odlikuju poboljšanom zdravstvenom funkcijom i/ili novim osvežavajućim ukusom se značajno povećalo. Jedna od mogućnosti je i obogaćivanje piva sa bioaktivnim jedinjenjima grožđa koja su odgovorna za dobro poznato blagotvorno dejstvo crvenih vina na zdravlje. U radu je ispitivan uticaj dodatka grožđa sorte Prokupac na fizičkohemijske karakteristike i kinetiku fermentacije specijalnih piva sa dodatkom grožđa, pri čemu su dobijeni rezultati poređeni sa kontrolnim lager pivom. Uticaj dodatka grožđa na aktivnost kvasca je takođe ispitivan. Početni ekstrakt, sadržaj alkohola, stepen prevrelosti, brzina fermentacije i razmnožavanje kvasca je bilo značajno veće kod piva sa dodatkom grožđa, zbog većeg sadržaja prostih šećera u grožđu u poređenju sa čistom sladovinom. Prema CIELab parametrima boje, boja piva sa dodatkom grožđa je bila žuta sa određenim udelom crvene, dok je kontrolno pivo bilo čiste žute boje. Povećanjem udela grožđa boja piva postaje tamnija i sa manjim udelom žute boje, dok je udeo crvene boje direktno proporcionalan sadržaju grožđa. Sadržaj fenolnih jedinjenja i antioksidativni kapacitet piva sa dodatkom grožđa je bio značajno veći u odnosu na kontrolno pivo, što znači da je pivo sa grožđem bolji izvor prirodnih antioksidanasa nego komercijalno lager pivo

Volatile Composition, Colour, and Sensory Quality of Spirit-Based Beverages Enriched with Medicinal Fungus Ganoderma lucidum and Herbal Extract

The multicomponent mixtures consisting of herbs and fungi are commonly used for the production of alcoholic beverages with potential health-promoting effects in many Asian countries. The medicinal fungus Ganoderma lucidum is one of the most important fungi used for spirit production. Although this fungus affects the aromatic complexity of spirits, only a small number of studies have focused on investigating the influence of G. lucidum on the aromatic profile and colour of spirits. The aim of the research is to evaluate the influence of adding G. lucidum and herbal extract on final concentrations of volatile compounds and sensory quality of several distillates. In this study, distillates (grain, plum, grape and wine) were used to produce new spirit-based beverages with the fungus G. lucidum only, or with the fungus and herbal extract. Fifty-nine aroma compounds were identified by GC-MS. The aromatic profiles were strongly influenced by the primary aromas of the distillates, but the addition of G. lucidum and herbal extract enriched the volatile fraction of distillates with a range of ethyl esters, with a fruity and floral fragrance. Higher alcohols, 1-propanol, 2-isobutanol and isoamyl alcohol, were the most abundant volatile compounds in the analyzed distillates and spirits. The lightness of distillates was from 60.7 to 63.6, and with the addition of Ganoderma it significantly decreased to the range from 43.6 to 50.5. The addition of the fungus also increased the intensity of red and yellow colours. The Ganoderma spirits scored very highly in sensory evaluation (17.6-18.3), significantly better than the spirits without any additions (16.1-16.9)

Serbian aromatized wine “Bermet”: Electrochemical, chemiluminescent and spectrophotometric determination of antioxidant activity

Serbian aromatized wine “Bermet” from grapes grown on Fruška Gora Mountain has been in production since the 15th century. Ten commercial Bermets produced according to the traditional procedure by different manufacturers, and six prepared within the scope of this study were assessed for antioxidant (AO) activity using electrochemical, chemiluminescent and spectrophotometric AO assays. Direct current polarographic assay based on the decrease of anodic current of [hydrogen(peroxido)(1-)]hydroxidomercury(II) complex formation in alkaline H2O2 solution at potential of mercury oxidation, chemiluminescent H2O2 scavenging assay, as well as commonly used spectrophotometric assays (2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) based Trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP)) were used. Total phenolic content (TPC) was determined by Folin–Ciocalteu assay. The results obtained were correlated using regression analysis, ANOVA and F-test. An integrated approach to AO capacity determination allowed a more comprehensive comparison between samples. The approach is based on the introduction of the relative antioxidant capacity index, calculated by assigning each AO assay equal weight, and by PCA analysis. In addition, the introduction of phenolic antioxidant coefficients, calculated as the ratio between individual AO capacity and TPC, enabled a better understanding of their relation

Novi proizvodi od maline dobijeni liofilizacijom

Freeze drying is relatively new process for drying fruit from frozen state. In distinction from classical drying, freeze drying make product with very little content of water, against maximal preservation of all nutritive matter in the product. These process is especially good for sensitive fruits at whom shall almost save typical flavor, color and vitamins. In this paper oversight of new raspberry products that can bee obtained by freeze drying process is given. Analysis of technological procedures for obtaining of whole freeze dried raspberry and freeze dried raspberry juice in powdered form is given. These technologies are relatively new in the world and with us still are not apply in industrial dimensions. .Liofilizacija predstavlja relativno nov postupak za sušenje iz smrznutog stanja. Za razliku od klasičnog sušenja, liofilizacijom se dobija proizvod sa vrlo malim sadržajem vode uz maksimalno očuvanje svih hranljivih materija u osušenom proizvodu. Ovaj postupak konzervisanja je posebno interesantan za osetljivo voće kod koga treba maksimalno očuvati karakterističnu aromu, boju i vitamine. U radu je data pregled novih proizvoda od maline koji se mogu dobiti postupkom liofilizacije. Data je analiza tehnoloških postupaka za dobijanje liofilizovanog celog ploda maline, kao i liofilizovanih sokova maline u prahu. Ove tehnologije su relativno nove u svetu, a kod nas se još uvek ne primenjuju u industrijskim razmerama.

Zakonski propisi u proizvodnji želiranih proizvoda

Once the new Serbian Regulation on the quality of fruit jams, jellies, marmalades and sweetened chestnut puree (101/2015) was issued, the former Regulation on the quality of fruit, vegetables, mushrooms and pectin preparations (01/79) ceased. Former Regulation was an excellent document, which had to be changed upon the harmonization of laws with European Union (EU). By interpreting the "old" regulations it is obvious that the share of fruit in the gelled product was very high, much higher than under the new regulation. The new Regulations of R. of Serbia recognize a categorization of the following nine products: jam, extra jam, jelly, extra jelly, marmalade, jelly marmalade, domestic marmalade ("domaća marmelada"), sweetened chestnut puree and pekmez. Domestic marmalade and pekmez weren't recognized in the Directive (2001/113/EC), but are result of harmonization of regulations and introduction of novelties that are specific to individual EU members. In terms of specific quality requirements, each of the nine groups is defined separately. The new Regulations (101/2015) define jam as a product containing some smaller portion of fruit (350g/kg), while the extra jam should not contain less than 450 g/kg of a fruit in the final product. It is noticeable that there are some distinctive differences relating the product quality in these two Regulations: jam and extra jam could contain a considerably smaller fruit content in the final product comparing the old regulations; the quality standards for domestic marmalade are the same as were for former marmalade. The quality is higher than quality of the best products of the other groups, such as extra jam. In case of domestic strawberry marmalade and strawberry extra jam, the fruit content of 800g/kg is almost twice times higher than of extra jam (450g/kg).U skladu sa Zakonom o bezbednosti hrane donet je "novi" Pravilnik o kvalitetu voćnih džemova, želea, marmelade, pekmeza i zaslađenog kesten pirea. Danom njegovog stupanja na snagu prestaje da važi "stari" Pravilnik o kvalitetu proizvoda od voća, povrća, pečurki i pektinskih preparata, u delu koji se odnosi na želirane proizvode. Izmene ovih propisa nisu bili rezultat zahteva struke ili potrošača za promenom, već su rezultat državnog opredeljenja za članstvom u Evropskoj uniji. Sadržaj suve materije morao je po "starim" propisima biti min. 65% za džem, odnosno min. 67% za marmeladu, pri čemu min. 6% mora poticati iz voća za džem, odnosno min. 7% za marmeladu. Po "novim" propisima sadržaj suve materije je min. 60%, osim za domaću marmeladu gde je min. 67%. Sadržaj voća se kod svih grupa kreće od 200g/kg do 450 g/kg, osim za domaću marmeladu od 350g/kg do 800g/kg. To jasno ukazuje da je i sadržaj šećera i sadržaj voća u finalnom proizvodu bio značajno viši po "starim" propisima nego po "novim" propisima. Upravo su to bili razlozi da se u "novim" propisima, usklađenim sa Evropskom unijom, uvede jedna nova grupa proizvoda koja će se zvati "domaća marmelada". Razlog za izdvajanje domaće marmelade od ostalih grupa je da se zadrži stari, prepoznatljiv i visok kvalitet proizvoda, a koji se nekada zvao samo marmelada