Effect of Pasteurization on Rheological Properties of White Carrot Juice

AbstractThe rheological behaviour of untreated and pasteurized white carrot juice was modelled to investigate the influence of temperature on viscosity and its fluid type. The research was conducted using a rotational viscometer at shear rates ranging from 1 to 100 s-1 and temperatures between 10 and 60°C. The rheological behaviour of untreated white carrot juice was well described by the Newtonian model while the pasteurized juice showed a pseudoplastic behaviour and was satisfactorily fitted to Ostwald-de Waele model. The Arrhenius equation adequately described the effect of temperature on the viscosity. The activation energies were depended on kind of fluid and were 15.41 and 5.90kJ/mol for untreated and pasteurized white carrot juice, respectively

Ocena czystości mikrobiologicznej wybranych komponentów pasz i mieszanek poddanych obróbce termicznej

Microorganisms which contaminate animal feeds pose a threat not only to animals but also indirectly to humans through their consumption of products of animal origin. The aim of the present study was to assess microbiological cleanness of selected resources and ready-made feed mixtures before and after thermal processing. The results indicated that the most bacteriologically contaminated resources were oats (Avena sativa), wheat middlings, wheat (Triticum vulgare), and poultry feed mixture KDKA F35%. The least contaminated were maize (Zea) and Prowit – feed mixture for livestock. The examined feed resources were contaminated with moulds, among which dominated: Aspergillus and Penicillium. The findings of bacteriological and mycological contamination assure instead of allow stating that thermal processing limits microbiological contamination of animal feeds. In order to protect the health of animals as well as consumers it seems advisable to seek new methods of thermal processing in the production of animal feeds to provide their high quality and safety.Mikroorganizmy zanieczyszczające pasze stanowią zagrożenia zarówno dla zwierząt, ale także pośrednio dla ludzi poprzez spożywanie produktów pochodzenia zwierzęcego. Celem niniejszej pracy była ocena czystości mikrobiologicznej wybranych surowców oraz gotowych mieszanek paszowych przed oraz po obróbce termicznej. Z przeprowadzonych badań wynika, że najbardziej zanieczyszczonymi bakteriologicznie surowcami był owies, śruta pszenna, pszenica oraz mieszanka paszowa dla drobiu KDKA F35%. Najmniej zanieczyszczeń posiadała kukurydza oraz mieszanka dla trzody Prowit. Badane surowce paszowe zanieczyszczone pleśniami, wśród których dominowały rodzaje: Aspergillus i Penicillium. Uzyskane wyniki badań zanieczyszczenia bakteriologicznego i mykologicznego pozwalają stwierdzić iż proces obróbki termicznej ogranicza zanieczyszczenie mikrobiologiczne pasz. W celu ochrony zdrowia zwierząt oraz konsumentów wydaje się być wskazane poszukiwanie nowych metod obróbki termicznej w produkcji pasz, aby zapewniać im wysoką jakość i bezpieczeństwo

Analysis of Selected Physicochemical Properties of Commercial Apple Juices

The paper presents the comparison of quality of six different commercial apple juices produced in Poland. The apple juices came from two different Polish companies. From each manufacturer three various juices were selected: two cloudy and clarified one produced as a mixture of different apple varieties. The following properties were evaluated: density, soluble solid content, viscosity, total phenolic contents, phenolic acid, and antiradical activity. The obtained results showed that three from fourth cloudy juices (M1Sz, M1A and M2A) differed from clarified juices. The highest differences were noticed for total phenolic contents, phenolic acids, antiradical activity and viscosity. The values of these properties ranged between 60.72–103.6 mg GAE·100-1 mL-1 for phenolic contents, 78.3–90.9% for antiradical activity and 2.68–5.79 mPa·s for viscosity. The remaining cloudy juice (M2Sz) was more similar to the clarified ones. The strong correlation between total phenolic content and antiradical activity of apple juices was found. The high correlation coefficient obtained between these features indicates that both producers do not apply excessive amounts of vitamin C during the production of cloudy apple juices. There was also a strong interrelation between the density of juice and solid soluble content. However, no correlation was found between the solid soluble content and the viscosity of the tested juices

Effect of Extraction Method and Thermosonication on Apple Juice Quality

This paper presents the results of a study on the influence of juice extraction and thermosonication methods on the content of microorganisms in juices stored under refrigeration and in ambient temperature. It was determined that the type of extraction device used influenced the content of microorganisms in juice. The lowest total content of mesophilic microorganisms was obtained in juice extracted on a piston press, and the highest was obtained using a centrifuge. The additional purpose was to evaluate the influence of ultrasonic treatment on selected parameters of apple juice quality: cloud value, antioxidant activity, total phenolic content, flavonoid content, and anthocyanin content. The ultrasound treatment of juice from the piston press was conducted at two levels of radiated sonic power so as to obtain sublethal and lethal temperatures of the juice. It was demonstrated that only ultrasound treatment within the range of lethal temperatures was sufficient to deactivate microorganisms. It was determined that thermosonication did not influence the deterioration of chemical properties of juices, with the exception of decreased anthocyanin content. The described method enables prolongation of the shelf life of fresh apple juice under refrigeration to 168 hours (7 days)

Technology for Apple Pomace Utilization within a Sustainable Development Policy Framework

The aim of this study was to develop a concept, within the framework of sustainable agriculture, for utilizing apple pomace as a valuable raw material in food production. The proposal includes a description of the production technology of four food products together with the characteristics of their chemical composition, wholesome compounds, and physical properties. These new products were developed on the basis of apple pomace and wheat bran. In the developed technology, heat treatment in a convection oven, treatment with infrared radiation, and two types of barothermic treatments, i.e., extrusion and granulation, were implemented as the principal methods. All of the proposed technologies allow for the use of pomace for the production of food products to be made directly in the home plant and are relatively easy to implement in small processing facilities. It was found that the product consisting of fragmented apple pomace (mass fraction: 75%) and wheat bran (mass fraction: 25%), obtained using infrared radiation treatment, had the greatest value in terms of wholesome characteristics among the products obtained. This product had high contents of fiber and simple sugars, the highest content of polyphenols among the obtained products, and the ability to scavenge free radicals. It was also the only one with partially preserved vitamin C. The proposed method for processing pomace for food is in line with the sustainable agriculture movement

Technology for Apple Pomace Utilization within a Sustainable Development Policy Framework

The aim of this study was to develop a concept, within the framework of sustainable agriculture, for utilizing apple pomace as a valuable raw material in food production. The proposal includes a description of the production technology of four food products together with the characteristics of their chemical composition, wholesome compounds, and physical properties. These new products were developed on the basis of apple pomace and wheat bran. In the developed technology, heat treatment in a convection oven, treatment with infrared radiation, and two types of barothermic treatments, i.e., extrusion and granulation, were implemented as the principal methods. All of the proposed technologies allow for the use of pomace for the production of food products to be made directly in the home plant and are relatively easy to implement in small processing facilities. It was found that the product consisting of fragmented apple pomace (mass fraction: 75%) and wheat bran (mass fraction: 25%), obtained using infrared radiation treatment, had the greatest value in terms of wholesome characteristics among the products obtained. This product had high contents of fiber and simple sugars, the highest content of polyphenols among the obtained products, and the ability to scavenge free radicals. It was also the only one with partially preserved vitamin C. The proposed method for processing pomace for food is in line with the sustainable agriculture movement

Optimization of the Ultrasound-Assisted Extraction of Bioactive Compounds from <i>Cannabis sativa</i> L. Leaves and Inflorescences Using Response Surface Methodology

This study investigated the effects of particle size and ultrasonic parameters on the yields of bioactive compounds extracted from the leaves and inflorescences of hemp. The total flavonoid and anthocyanin contents were determined using the spectrophotometric method. The response surface methodology (RMS) was employed to optimize the yield of bioactive substances. On the basis of the developed model, the highest flavonoid yield was obtained under the following extraction conditions: particle size, 0.59 mm; extraction time, 10.71 min; ultrasound intensity, 7.13 W∙cm−2; extraction yield, 9.28 mg QE∙g−1; determination coefficient, R2 = 0.97. The optimal conditions for extracting anthocyanins were as follows: particle size, 0.25 mm; extraction time, 15 min; ultrasound intensity, 8.60 W∙cm−2; extraction efficiency, 20.27 mg Cy-GE∙100 g−1; determination coefficient, R2 = 0.87. This study helped confirm the importance of pulsed ultrasound-assisted extraction in obtaining bioactive compounds from hemp

Ocena wybranych parametrów technicznych procesu tłoczenia oleju z nasion soi

The objective of the paper was to determine the impact of the value of the oil pressing pressure with the cold pressing method in a screw press on the pressing course and performance. Varied values of pressure were obtained through the use of three replaceable attachments of the pressing unit with a varied diameter of the outlet conduit (ф1=2 mm, ф2=4 mm and ф3=6 mm). The soya oil pressing process perfor-mance was determined in relation to the applied attachment and the soya cultivar. Seeds of 7 Polish non-genetically modified soya cultivars constituted research material. It was proved that both variable pressure values and the used soya cultivars have impact on the pressing performance. Based on the analysis of the obtained research results it was proved that varied technical parameters and soya cultivars influence both the process performance and the remaining parameters and pressing conditions.Celem pracy było określenie wpływu zmiennych wartości ciśnienia wytłaczania oleju metodą tłoczenia na zimno w prasie ślimakowej na przebieg i wydajność tłoczenia. Zróżnicowane wartości ciśnienia uzyskiwano poprzez zastosowanie trzech wymiennych końcówek zespołu tłoczącego o różnej średnicy kanału wylotowego (ф1=2 mm, ф2=4 mm i ф3=6 mm). Określano wydajność procesu tłoczenia oleju sojowego w zależności od zastosowanej końcówki oraz odmiany soi. Materiałem do badań były nasiona 7 polskich odmian soi niemodyfikowanej genetycznie. Wykazano, iż wpływ na efektywność wytłaczania mają zarówno zmienne wartości ciśnienia jak i wykorzystane odmiany soi. W oparciu o analizę uzyskanych wyników badań potwierdzono, iż zróżnicowane parametry techniczne i odmiany soi mają wpływ zarówno na wydajność tego procesu, jak i jego pozostałe parametry i warunki tłoczenia

Effect of the black chokeberry (Aronia melanocarpa (Michx.) Elliott) juice acquisition method on the content of polyphenols and antioxidant activity.

The primary objective of the study was to determine the effect of process conditions on extraction efficiency and the total amount of released polyphenols and antioxidant activity (AA) in black chokeberry juice. The study samples were fruits of black chokeberry (Aronia melanocarpa (Michx.) Elliott) cv. Galicjanka. In the study, two kinds of presses-piston press and twin gear juice extractor-were used, and two raw material pretreatment methods-freezing and thawing and enzymatic liquefaction-were applied. The study showed that pressing efficiency depends on the design of press and the nature of pretreatment. The highest pressing efficiency was obtained using the twin gear juice extractor. Enzymatic liquefaction of shredded fruits significantly increased the efficiency of pressing by the piston press. The type of press and the pretreatment method used had an effect on the quality traits of the extracted juices. The highest content of soluble solids was obtained for fruits not subjected to any pretreatment and pressed using the twin gear press. The highest total phenolic content was obtained in juice extracted using the piston press from shredded fruits subjected to enzymatic treatment at 45°C. A higher total phenolic content was also a characteristic of juice obtained from fruits not subjected to any pretreatment and extracted using the twin gear press. The capacity of the black chokeberry juices for free radical quenching oscillated around the level of approximately 90%. The study showed that the application of suitable processing methods is necessary for the acquisition of products with desirable quality traits

Optimization of the Ultrasound-Assisted Extraction of Bioactive Compounds from Cannabis sativa L. Leaves and Inflorescences Using Response Surface Methodology

This study investigated the effects of particle size and ultrasonic parameters on the yields of bioactive compounds extracted from the leaves and inflorescences of hemp. The total flavonoid and anthocyanin contents were determined using the spectrophotometric method. The response surface methodology (RMS) was employed to optimize the yield of bioactive substances. On the basis of the developed model, the highest flavonoid yield was obtained under the following extraction conditions: particle size, 0.59 mm; extraction time, 10.71 min; ultrasound intensity, 7.13 W&#8729;cm&minus;2; extraction yield, 9.28 mg QE&#8729;g&minus;1; determination coefficient, R2 = 0.97. The optimal conditions for extracting anthocyanins were as follows: particle size, 0.25 mm; extraction time, 15 min; ultrasound intensity, 8.60 W&#8729;cm&minus;2; extraction efficiency, 20.27 mg Cy-GE&#8729;100 g&minus;1; determination coefficient, R2 = 0.87. This study helped confirm the importance of pulsed ultrasound-assisted extraction in obtaining bioactive compounds from hemp