Istražen je utjecaj temperature (80-120 C) i vremena (5-50 min) na stabilnost antocijana (cijanidin-3-glukozilrutinozida, cijanidin-3-rutinozida i cijanidin-3-glukozida), kvercetin-3-glukozida i ...fenolnih kiselina (klorogenske, neoklorogenske, p-kumarinske i ferulinske kiseline) u liofiliziranoj pasti višnje maraske. Brzina razgradnje antocijana, kvercetin-3-glukozida i fenolnih kiselina slijedila je kinetiku reakcija prvoga reda. Najnestabilniji od svih antocijana bio je cijanidin-3-glukozid, a od fenola p-kumarinska i neoklorogenska kiselina. Energije aktivacije za degradaciju antocijana kretale su se od 41,88 (za cijanidin-3-glikozilrutinozid) do 54,76 kJ/mol (za cijanidin-3-glukozid), a za degradaciju ostalih fenola od 8,12 (za klorogensku kiselinu) do 26,70 kJ/mol (za neoklorogensku kiselinu). Povećanjem temperature od 80 na 120 C povećala se konstanta brzine reakcije (k) za cijanidin-3-glukozilrutinozid s 2,15·10-2 na 8,48·10-2 min-1, za p-kumarinsku kiselinu s 1,12·10-2 na 2,49·10-2 min-1, a za kvercetin-3-glukozid s 1,47·10-2 na 2,57·10-2 min-1. Dobiveni rezultati pokazuju da je vrijeme poluraspada antocijana bilo u rasponu od 32,10 min za cijanidin-3-glukozilrutinozid do 45,69 min za cijanidin-3-rutinozid pri 80 C, a ostalih fenolnih spojeva od 43,39 min za neoklorogensku kiselinu do 66,99 min za klorogensku kiselinu. Zaključeno je da temperatura i vrijeme zagrijavanja značajnije utječu na degradaciju antocijana nego na degradaciju ostalih fenola.
U radu je opisan razvoj sublingvalnih tableta sildenafil citrata (SILD) raspršivih u ustima (ODST) za terapiju plućne arterijske hipertenzije (PAH), sa svrhom povećanja raspada nakon peroralne ...primjene, povećanja oslobađanja i bioraspoloživosti. Primijenjena je metoda izravne kompresije čvrstih disperzija (SD) sildenafila i poloksamera 188 i liofilizacija, a u izradi su upotrjebljena različita pomoćna sredstva. Evaluirana su fizikokemijska svojstva te oslobađanje ljekovite tvari iz tableta. Osim toga, na dobrovoljcima je uspoređivana bioraspoloživost sildenafila iz ODST-a i standardnih tableta za peroralnu primjenu. Uklapanje SD poloksamera 188 u sublingvalne tablete uz Pharmaburst i korištenje izravne kompresije povećalo je oslobađanje SILD-a tako da je nakon 7 minuta 100 % lijeka bilo otopljeno. Međutim, liofilizacija se pokazala superiornom za povećanje oslobađanja jer se 100 % SILD-a oslobodilo nakon samo jedne minute. toviše, in vivo studije su pokazale da je AUC0-12 liofiliziranih tableta bila značajno veća nego iz tableta dobivenih izravnim komprimiranjem, uz vrijednosti za bioraspoloživost od 159,81, odnosno 140,85 % u odnosu na komercijalno dostupne proizvode.
Cilj rada je bio ispitati utjecaj šećera (glukoze, fruktoze, saharoze i trehaloze) na očuvanje polifenolnih
spojeva i antioksidativnu aktivnost kaša od jabuka pripremljenih zamrzavanjem i ...dehidratacijom
(liofilizacijom). Istraživanje je obuhvatilo ispitivanje dviju sorti jabuka (Granny Smith i Gold Rush) kroz
dvije proizvodne sezone, a također je obuhvatilo i mogućnost iskorištavanja nusprodukta industrije
voća, koru jabuke, koja se često tretira kao otpad pri preradi, a kojom bi se (kao dodatak) obogaćivala
kaša od jabuka.
Rezultati su pokazali da dodatak šećera i praha kore jabuka znakovito utječe na očuvanje odnosno
povećanje polifenolnih spojeva i antioksidacijske aktivnosti procesiranih kaša jabuka u odnosu na
kaše jabuka bez dodataka. Od ispitivanih šećera trehaloza je najviše utjecala na očuvanje promatranih
parametara dok je glukoza imala najmanji utjecaj.
Nakon skladištenja uzorci s dodatkom šećera i praha kore jabuka su i dalje imali veći sadržaj polifenola i antioksidacijsku aktivnosti u usporedbi s kontrolnim uzorcima.
The aim of this research was to determine the influence of sugars (glucose, fructose, sucrose and trehalose) on retention of polyphenols and antioxidative activity of processed (frozen and freeze-dried) apple puree. The research included examination of two apple varieties (Granny Smith and the Gold Rush) through two production seasons, and also include the possibility of exploiting by-product from fruit industry, apple peels, which are often treated as waste for enrichment of apple puree.
Results showed that the addition of sugars and apple peel powder resulted in retention of polyphenols and antioxidative activity in comparison to samples without addition of additives. The addition of trehalose had the highest impact on polyphenol and antioxidant activity retention and glucose the lowest.
After storage samples with sugar and apple peel powder addition had higher content of polyphenols and antioxidative activity in comparison to control samples.
In the course of several years of use of lyophilization for long term preservation of oxytetracycline producing Streptomyces strains, their morphogenetic stability and the stability of their ...antibiotic yields were verified.
The described process of lyophilization, as regards the viability and morphogenetic stability of both sporogenous and the asporogenous forms, has been proved very successful, with few exceptions. Data are given in Table II. Viable spore counts of 40—90.8% were satisfactory.
The growth of lyophilized cultures on agar medium (P—1) did not differ much from the growth of non-lyophilized (control) cultures: the populations of the cultures invariably retained all essential »starting« morphological characteristics. Only in a small number of cases alterations in some lyophilized cultures in comparison with the »starting« cultures were observed (e. g. T6—429, T6—483 and BIM—197 in Table II). These differences were manifested by the appearance of small colonies (5%), the disappearance of drops of exudate from the colonies center, or by differences in intensity of soluble pigment in the medium. No reliable explanation has been found for this phenomenon. It can probably be ascribed to microecological conditions (different composition of medium, temperature and the like).
The growth of lyophilizates in a liquid medium (P—2) owing to the almost complete anabiosis, was obviously somewhat slower (it averaged 10—16 hours) in comparison to the control cultures; the lyophilized asporogenous cultures, however, grew faster (4—6 hours) than the lyophilized sporogenous ones (see Table II).
It has been proved that the remaining moisture in the lyophilizates is the limiting factor in attaining anabiosis and that, therefore, it is necessary to maintain the moisture within a narrow range and at a low level.
The quality of cotton plugs considerably influences the process of lyophilization, especially at the stage of drying in the vacuum, so that full attention must be paid to the preparation of these plugs, particularly to their hardness.
With regard to the stability in Oxytetracycline antibiotic yields (Table III), the tested lyophilizates have given different yields in comparison to the control cultures, in spite of the same testing conditions in the course of experiments, especially in the laboratory.
Tests with some lyophilized cultures were repeated, and results obtained showed approximately the same differences (Table III, figures in brackets). The yields were often higher than those of the control.
The obtained Oxytetracycline yields on a production scale were very favourable and uniform, even in the course of prolonged use of lyophilized cultures for the preparation of inoculum.
The following conclusions are the result of many years of work and of data presented here:
1) The described process of lyophilization, as a whole, is suitable for a long term preservation of tested Oxytetracycline producing Streptomyces strains.
2) Both apparatuses used for lyophilization are suitable for the purpose described and produce lyophilizates of uniform quality. The model DELTA I/a is of higher capacity and therefore more suitable for production purposes, and for the maintaining of larger collections of cultures.
3) The optimum freezing temperature of the cultures is — 50 to — 55 °C.
4) The remainder of moisture in the lyophilizates — because it is a determinant factor in attaining anabiosis on which the stability of cultures depends — must be kept at the same, previously verified level.
5) Lyophilized cultures retained constant Oxytetracycline yields in the course of the four-year storage.
6) The porousness and the hardness of the microbiological cotton plugs must be standardized for the sake of more successful lyophilization process.
Iako skup, postupak liofilizacije veoma je pogodan za konzerviranje mliječnih proizvoda. U ovom radu autor je ukazao na mogućnost umanjenja cijene liofilizacije fermentiranog mliječnog proizvoda - ...kiselog mlijeka pripremajući proizvod na ugušćenom mlijeku. Također iz rezultata rada se vidi da su optimalni uvjeti za razvoj startera za kiselo mlijeko kod ugušćenja 18-22 % suhe tvari mlijeka, a da je povećanje suhe tvari iznad 40 % jako produžilo vrijeme zakiseljavanja mlijeka.
Zahtjevi potrošača za što kvalitetnijim prehrambenim proizvodima danas su izraženiji
nego ikada. Kako bi se udovoljilo zahtjevima potrošača, velika pažnja se posvećuje razvoju
novih proizvoda ili pak ...poboljšavanju svojstava, a time i kvalitete, već postojećih proizvoda
(npr. dodatkom različitih sastojaka, poboljšanjem procesa proizvodnje, uključujući pakiranje i
drugo). Najznačajniji čimbenici kvalitete su aroma, boja i tekstura.
Paste od jagoda se koriste kao punilo za čokolade, energetske pločice i druge
proizvode koji sadrže voće. U industriji se paste od jagode pripremaju procesom evaporacije i
bez dodatka šećera trehaloze. Kako bi se poboljšala kvaliteta voćne paste osim industrijskog
postupka pripreme upotrijebljena je i liofilizacija, te je ispitivan utjecaj dodatka različitih
koncentracija trehaloze na aromu, teksturu, boju, sadržaj antocijana i antioksidativna
aktivnost. Također je praćen utjecaj različitih načina pakiranja (u atmosferi dušika i u zraku)
tijekom skladištenja na sobnoj temperaturi tijekom 5 mjeseci na aromu, boju i teksturu.
Trehaloza je jedan od najstabilnijh šećera. S obzirom da je razvijen enzimski proces
njezine proizvodnje koji je uvelike smanjio njenu cijenu, očekuje se sve veća primjena
trehaloze u prehrambenoj industriji zbog njezinog pozitivnog djelovanja na različita svojstva
kvalitete proizvoda.
Dodatak trehaloze uzrokovao je promjenu svojstava paste od jagode bez obzira jesu li
uzorci bili podvrgnuti evaporiraciji ili liofilizaciji u odnosu na uzorke bez dodatka trehaloze.
Sadržaj voćnih estera se je povisio dodatkom trehaloze u odnosu na uzorke bez dodatka
trehaloze. Trehaloza je također pozitivno djelovala na teksturu, očuvanje boje i sadržaj
antocijana u uzorcima.
Liofilizirani uzorci su bili kvalitetniji u odnosu na uzorke proizvedene evaporiranjem.
Sadržaj voćnih estera, očuvanje boje i sadržaj antocijana je bio veći u liofiliziranim uzorcima
nego u evaporiranim.
Nakon skladištenja (5 mjeseci), uzorci s dodanom trehalozom su i dalje imali veći
sadržaj voćnih estera i antocijana.
Today, costumer’s demands for higher quality of food products are more pronounced
than ever. To satisfy costumer’s demands, high attention is paid to new product development
or improvement of properties of existing product (by addition of different ingredients,
improvement of processing, packaging ect.). The most important quality factors are aroma,
texture and colour.
Strawberry pastes are used as fillings for chocolates, energy bars and other products
that contain fruit. In industry, strawberry pastes are prepared by evaporation and without
trehalose addition. To improve quality of this product, next to industrial process of
preparation, freeze-drying was used. Its influence and influence of different concentrations of
trehalose addition on aroma, texture, colour, anthocyanin content and free radical scavenging
activity were studied. Influence of different atmospheres (nitrogen and air) for packaging
during storage for 5 months at room temperature on mentioned properties were also studied.
Trehalose is one of most stable sugars. Since enzymatic process for its production is
developed its price is lower, so it is expected that its use in food industry will grow because
trehalose have positive effect on different quality properties of products.
Addition of trehalose caused property change of strawberry pastes in both evaporated
and freeze-dried samples in comparation to samples without trehalose addition. Fruity esters
content was higher in samples when trehalose was added. Trehalose also had positive effect
on texture, colour degradation and retention of anthocyanins in samples.
Freeze-drying also improves quality of product. Fruity esters content, retention of
anthocyanins and retention of colour were higher in freeze-dried samples.
After storage, samples with trehalose added had higher content of fruity esters and
anthocyanin content.
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