Physical and Chemical Properties of Vegetable Films Based on Pumpkin Purée and Biopolymers of Plant and Animal Origin.

Highly methylated apple pectin (HMAP) and pork gelatin (PGEL) have been proposed as gelling agents for pumpkin purée-based films. Therefore, this research aimed to develop and evaluate the physiochemical properties of composite vegetable films. Granulometric analysis of film-forming solutions showed a bimodal particle size distribution, with two peaks near 25 µm and close to 100 µm in the volume distribution. The diameter D4.3, which is very sensitive to the presence of large particles, was only about 80 µm. Taking into account the possibility of creating a polymer matrix from pumpkin purée, its chemical characteristic was determined. The content of water-soluble pectin was about 0.2 g/100 g fresh mass, starch at the level of 5.5 g/100 g fresh mass, and protein at the level of about 1.4 g/100 g fresh mass. Glucose, fructose, and sucrose, the content of which ranged from about 1 to 1.4 g/100 g fresh mass, were responsible for the plasticizing effect of the purée. All of the tested composite films, based on selected hydrocolloids with the addition of pumpkin purée, were characterized by good mechanical strength, and the obtained parameters ranged from about 7 to over 10 MPa. Differential scanning calorimetry (DSC) analysis determined that the gelatin melting point ranged from over 57 to about 67 °C, depending on the hydrocolloid concentration. The modulated differential scanning calorimetry (MDSC) analysis results exhibited remarkably low glass transition temperature (Tg) values, ranging from -34.6 to -46.5 °C. These materials are not in a glassy state at room temperature (~25 °C). It was shown that the character of the pure components affected the phenomenon of water diffusion in the tested films, depending on the humidity of the surrounding environment. Gelatin-based films were more sensitive to water vapor than pectin ones, resulting in higher water uptake over time. The nature of the changes in water content as a function of its activity indicates that composite gelatin films, with the addition of pumpkin purée, are characterized by a greater ability to adsorb moisture from the surrounding environment compared to pectin films. In addition, it was observed that the nature of the changes in water vapor adsorption in the case of protein films is different in the first hours of adsorption than in the case of pectin films, and changes significantly after 10 h of the film staying in an environment with relative humidity RH = 75.3%. The obtained results showed that pumpkin purée is a valuable plant material, which can form continuous films with the addition of gelling agents; however, practical application as edible sheets or wraps for food products needs to be preceded with additional research on its stability and interactions between films and food ingredients.

Quality assessment of cold-pressed strawberry, raspberry and blackberry seed oils intended for cosmetic purposes.

BACKGROUND: Cold-pressed berry seed oils are used for consumption and other applications including skin and hair care. They are natural products which gain the attention of customers. In this study, strawberry, raspberry and blackberry seed oils used for cosmetic purposes, purchased from three different European producers, were analyzed. The aim of the study was to assess the quality and oxidative stability of the berry fruit oils, thus they were analyzed after purchase and after 4 and 8 weeks of storage at room temperature. METHODS: Acid and peroxide values were determined in the tested oils, as was oxidative stability, which was measured using pressure differential scanning calorimetry (PDSC). Additionally, fatty acid profiles and thei. RESULTS: nd. Cold-pressed berry seed oils are used for consumption and other applications including skin and hair care. They are natural products which gain the attention of customers. In this study, strawberry, raspberry and blackberry seed oils used for cosmetic purposes, purchased from three different European producers, were analyzed. The aim of the study was to assess the quality and oxidative stability of the berry fruit oils, thus they were analyzed after purchase and after 4 and 8 weeks of storage at room temperature. Materials and methods. Acid and peroxide values were determined in the tested oils, as was oxidative stability, which was measured using pressure differential scanning calorimetry (PDSC). Additionally, fatty acid profiles and their distribution at sn-1,3 and sn-2 positions of triacylglycerols were characterized. Results, principal. Most of the fatty acids of the tested berry seed oils are polyunsaturated fatty acids (67.04-74.95%). The results show the low quality of the tested oils in terms of oxidative stability (high peroxide values: 21.9-249.6 mEq O2/kg oil). CONCLUSIONS: Based on this study, it is necessary to evaluate the effects of these products on the body. Moreover, standards clarifying the oxidation of cosmetic oils should be set internationally.

Simultaneous Production of Lipids and Carotenoids by the Red Yeast Rhodotorula from Waste Glycerol Fraction and Potato Wastewater.

AbstractThe objective of this study was to determine the possibility of simultaneous biosynthesis of lipids and carotenoids by the Rhodotorula yeast strains in media with waste glycerol and deproteinized potato wastewater and to determine the level of pollution reduction by media. On the basis of results obtained during the yeast microcultures in the Bioscreen C system, it was found that potato wastewater and glycerol can be used as components of media for Rhodotorula glutinis, Rhodotorula mucilaginosa, and Rhodotorula gracilis yeast strains. The amount of glycerol added to media higher than 10% significantly decreased the growth rate of yeast. The results of yeast culture in the laboratory shaker flasks showed a possibility of simultaneous production of lipids and carotenoids by R. glutinis, R. mucilaginosa, and R. gracilis yeast strains during cultivation in media containing only waste glycerol and deproteinized potato wastewater. A higher intracellular lipid content (approximately 15 g/100 gd.w.) was obtained for R. mucilaginosa and R. gracilis yeast biomass after cultivation in experimental media with waste glycerol and potato wastewater. In conclusion, the yeast grown in media with potato wastewater supplemented with 3% or 5% glycerol synthesized carotenoids, and their content in biomass did not exceed 230 µg/gd.w.

Effect of initial pH of medium with potato wastewater and glycerol on protein, lipid and carotenoid biosynthesis by Rhodotorula glutinis

Background: Rhodotorula glutinis is capable of synthesizing numerous valuable metabolites with extensive potential industrial usage. This paper reports the effect of initial culture medium pH on growth and protein, lipid, and carotenoid biosynthesis by R. glutinis. Results: The highest biomass yield was obtained in media with pH 4.0­7.0, and the value after 72 h was 17.2­19.4 gd.w./L. An initial pH of the medium in the range of 4.0­7.0 has no significant effect on the protein (38.5­41.3 g/100 gd.w.), lipid (10.2­12.7 g/100 gd.w.), or carotenoid (191.7­202.9 µg/gd.w.) content in the biomass or on the profile of synthesized fatty acids and carotenoids. The whole pool of fatty acids was dominated by oleic (48.1­53.4%), linoleic (21.4­25.1%), and palmitic acids (13.0­15.8%). In these conditions, the yeast mainly synthesized torulene (43.5­47.7%) and ß-carotene (34.7­38.6%), whereas the contribution of torularhodin was only 12.1­16.8%. Cultivation in medium with initial pH 3.0 resulted in a reduction in growth (13.0 gd.w./L) and total carotenoid (115.8 µg/gd.w.), linoleic acid (11.5%), and torularhodin (4.5%) biosynthesis. Conclusion: The different values of initial pH of the culture medium with glycerol and deproteinized potato wastewater had a significant effect on the growth and protein, lipid, and carotenoid biosynthesis by R. glutinis.

Determination of lipid and phenolic fraction in two hazelnut (Corylus avellana L.) cultivars grown in Poland.

The fatty acid, tocopherol, sterol, phospholipid and phenolic compositions of Polish hazelnuts (Katalonski and Webba Cenny) were examined. Particularly, free+esterified and bound tocopherol, sterol and phenolic compounds were determined. The major fatty acids found in hazelnuts were oleic and linoleic acids. α-Tocopherol was the most abundant tocopherol accounting for 90-92% of the total content. Bound tocopherols represented 45.5% and 21.7% of total tocopherols in Katalonski and Webba Cenny cultivar, respectively. Total free+esterified sterols were between 62.0% and 75.7% of total sterols and ß-sitosterol was the first sterol in the two samples. Phosphatidylcholine was the most common phospholipid, accounting for 72.2% for Katalonski and 67.5% Webba Cenny, respectively. The most abundant fatty acids in the phospholipid fraction were oleic equally with palmitic acids. Twelve free and six bound phenolic compounds were identified and quantified in hazelnut kernel, instead nine free and six bound phenolic compounds were determined in hard shell.