Application of Polyphenol-Loaded Nanoparticles in Food Industry

Nanotechnology is an emerging field of science, and nanotechnological concepts have been intensively studied for potential applications in the food industry. Nanoparticles (with dimensions ranging from one to several hundred nanometers) have specific characteristics and better functionality, thanks to their size and other physicochemical properties. Polyphenols are recognized as active compounds that have several putative beneficial properties, including antioxidant, antimicrobial, and anticancer activity. However, the use of polyphenols as functional food ingredients faces numerous challenges, such as their poor stability, solubility, and bioavailability. These difficulties could be solved relatively easily by the application of encapsulation. The objective of this review is to present the most recent accomplishments in the usage of polyphenol-loaded nanoparticles in food science. Nanoparticles loaded with polyphenols and their applications as active ingredients for improving physicochemical and functional properties of food, or as components of active packaging materials, were critically reviewed. Potential adverse effects of polyphenol-loaded nanomaterials are also discussed

Exploring Regulatory Obstacles to the Development of Short Food Supply Chains: Empirical Evidence from Selected European Countries

This paper explores the challenges in meeting the regulatory requirements of short food supply chains in 9 European countries based upon findings from the European H2020 3-year project “SMARTCHAIN”. The assessments of the barriers that small food producers face in meeting different regulatory requirements are presented. Drawing on the results of 10 multi-actor workshops that involved 124 participants, the most problematic policy frameworks for short food supply chains and key obstacles in different regulatory requirements are summarized. This research shows that current EU and national regulation is an obstacle to the development of short food supply chains, meaning that additional efforts are needed to tailor the regulations to small food producers involved in short supply chains. Furthermore, it is necessary to consider the introduction of more effective support measures for short food supply chain

‐sitosterol and gentisic acid loaded 1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphocholine liposomal particles

The aim of the present study was the examination of the impact of -sitosterol andgentisic acid on the characteristics of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine(DPPC) liposomal particles: (a) bilayer permeability (fluorescence spectroscopy),(b) particle size, polydispersity index (PDI) and zeta potential (photon correlationspectroscopy) and (c) thermal properties (differential scanning calorimetry). -sitosterol induced the increase of liposomal bilayer rigidity, due to rearranging ofthe phospholipid chains, while gentisic acid enhanced the membrane fluidity, dueto the reduced orderliness and the increase of phospholipid dynamics. The inclusionof -sitosterol in liposomes caused a significant increase in particle diameterand PDI, while the encapsulation of gentisic acid did not have influence on particlesize distribution. Apart from that, the presence of -sitosterol resulted in thesignificant zeta potential increase, and thus a better stability of liposomal spheres(in the absence and in the presence of gentisic acid). -sitosterol decreased maintransition temperature (Tm) and phase transition enthalpy (H), and caused thedisappearance of the pre-transition peak as well, whereas the presence of gentisicacid produced a slight decrease in Tm and increase of H. Therefore, gentisic acidhad more favourable, stabilizing interactions with phospholipids than -sitosterol.Thus, it can be concluded that -sitosterol is located in the bilayer interior betweenphospholipids acyl chains, and gentisic acid is incorporated near the outer leaflet ofthe phospholipid membrane, next to the polar head groups. -sitosterol and gentisicacid loaded DPPC liposomal particles have a potential to be used in food andpharmaceutical products, due to the important individual and possible synergisticbeneficial health properties of -sitosterol and gentisic acid

Koncentracija trans- i cis-rezveratrola u vinima proizvedenim u Srbiji

Resveratrol, which occurs in two isomeric forms, trans and cis, is a phytoalexin with numerous pharmacological activities, such as anti-cancer, antiviral, neuroprotective and anti-aging. Red wine is the main source of the compound and an easy way of including resveratrol in the human diet. In this study, the most popular commercial Serbian wines (red, white and rose-type) were analyzed for their content of trans- and cis-resveratrol. The analysis was performed by HPLC with a UV detector. Prior to the injection, phenolic compounds were extracted onto a LiChrolut RP18 bonded silica cartridge. The concentration of trans-resveratrol ranged from 0.11 to 1.69 mg L-1 and cis-resveratrol from 0.12 to 1.49 mg L-1.Metodom tečne hromatografije (HPLC) ispitan je sadržaj slobodnog oblika trans- i cis-rezveratrola u osamnaest komercijalnih uzoraka (10 crvenih, 7 belih i 1 roze) srpskih vina. Svi uzorci su pre hromatografije ekstrahovani SPE tehnikom na LiChrolut RP18 koloni. trans-Rezveratrol je detektovan u 17 od 18 analiziranih uzoraka vina sa prosečnom koncentracijama od 0,78 mg l-1 za crvena vina i 0,23 mg l-1 za bela vina. Najviša koncentracija trans-rezveratrola je nađena u uzorku crvenog vina Cabernet Sauvignon berbe 2002 godine. cis-Rezveratrol je detektovan u 12 od 18 analiziranih uzoraka vina sa prosečnom koncentracijom 0,55 mg l-1 za crvena vina, dok je u belim vinima od analiziranih 7 uzoraka detektovan samo u 2 uzorka sa koncentracijama 0,12 i 0,49 mg l-1. Visok sadržaj cis-rezveratrola u nekim uzorcima je verovatno posledica izomerizacije trans- u cis-rezveratrol tokom procesa proizvodnje vina

Fluorimetrijska analiza permeabilnosti lipozomalnih membrana

The present study provides insight into changes in the liposomal membrane fluidity as a result of variation of structural components (two types of standard phospholipids - 1,2-dipalmitoyl-sn-glycerero3-phosphocholine, i.e. DPPC and 1-palmitoyl-2-oleoylglycerol-3-phosphocholine, i.e. POPC, one type of phospholipid mixture - Lipoid H and sterols - cholesterol and b-sitosterol), as well as variation in sterol concentration (5-50%). Fluorescence spectroscopy (anisotropy, r) has shown that DPPC liposomal membranes were more rigid compared to POPC and Lipoid H lipid bilayers. Furthermore, the increment of sterol concentration has caused a decrease in the membrane fluidity in all liposomal samples. On the other hand, phospholipid bilayers containing b-sitosterol has possessed better fluidity in comparison to their cholesterol parallels. Higher permeability of b-sitosterol liposomal membranes, as well as the beneficial effects of phytosterol on human health, favor the use of b-sitosterol in the preparation of liposomes as components of food, pharmaceutical and cosmetic products.Prikazana studija daje uvid u promene fluidnosti lipozomalne membrane koje nastaju kao posledica promene strukturnih komponenata lipozoma (dve vrste standardnih fosfolipida - 1,2-dipalmitoil-snglicero-3-fosfoholin, odnosno DPPC i 1-palmitoil-2-oleoil-sn-glicero-3-fosfoholin, odnosno POPC, jedne vrste komercijalne fosfolipidne smeše - Lipoid H i sterola - holesterol i b-sitosterol), kao i promene udela sterola (0-50 mol %). Fluorimetrijska spektrofotometrija (anizotropija, r) pokazala je da su DPPC lipozomalne membrane bile rigidnije u poređenju sa POPC i Lipoid H lipidnim dvoslojima. Pored toga, povećenje koncentracije sterola prouzrokovalo je smanjenje permeabilnosti membrane u svim lipozomima. Sa druge strane, fosfolipidni dvosloji koji su sadržali b-sitosterol pokazali su veću fluidnost u poređenju sa njihovim paralelama sa holesterolom. Bolja permeabilnost b-sitosterol lipozomalnih membrana, kao i blagotvorni uticaji fitosterola na zdravlje ljudi favorizuju primenu b-sitosterola u pripremi lipozoma kao sastavnih delova prehrambenih, farmaceutskih i kozmetičkih proizvoda

Plasmolyzed Yeast Cells as a Potential Wall Material for Probiotic Bacteria

The beneficial effects of probiotics are severely limited due to their low stability during production and storage. Encapsulation of probiotic cells remains the main strategy to overcome this problem, and in this regard, the use of yeast cells may have potential. Viable, sonicated and thermally treated yeast cells as well as yeast cell wall polymers have been shown to promote the growth and survival of probiotic bacteria; however, the effects of plasmolyzed yeast have not yet been investigated. Therefore, the aim of this work was to evaluate the potential of plasmolyzed yeast cells for maintaining the viability of probiotic bacteria. Plasmolysis of Saccharomyces uvarum yeast cells was performed using a 10% NaCl solution (55 °C, 48 h). The cells were then washed, spray-dried and mixed with a previously prepared Lactiplantibacillus plantarum 299v culture (DSM 9843) in two ratios (1:1 and 2:1, w/w). Finally, the mixtures were freeze-dried. The viability of the probiotic cells was assessed after encapsulation and every two weeks during three months of storage under refrigerated conditions using the plate count method. In addition, water activity and morphology analyses were performed and the auto/coaggregation properties of the cells were investigated. After storage, the number of viable cells in both formulations remained above 7 log CFU/g, i.e. above the minimum required for probiotic benefits. The obtained powders showed satisfactory water activity, while optical microscopy and aggregation assays indicate that the protective effect of the yeast may be due to direct cell-to-cell contact. The results suggest that plasmolyzed yeast cells have the potential to serve as wall material for probiotic bacteria by maintaining their viability during freezing and storage. Further studies are needed to gain a better insight into the properties of the encapsulates under gastrointestinal conditions and in food matrices.Apstrakt je greškom izdavača izostavljen u samoj knjizi apstrakata pa se, budući da štampanje korigovane verzije knjige nije bilo izvodljivo, uz apstrakt prilaže potvrda o učešću na konferenciji u formi memoranduma

Freeze versus Spray Drying for Dry Wild Thyme (Thymus serpyllum L.) Extract Formulations: The Impact of Gelatin as a Coating Material

Freeze drying was compared with spray drying regarding feasibility to process wild thyme drug in order to obtain dry formulations at laboratory scale starting from liquid extracts produced by different extraction methods: maceration, heat-, ultrasound-, and microwave-assisted extractions. Higher powder yield (based on the dry weight prior to extraction) was achieved by freeze than spray drying and lower loss of total polyphenol content (TPC) and total flavonoid content (TFC) due to the drying process. Gelatin as a coating agent (5% w/w) provided better TPC recovery by 70% in case of lyophilization and higher powder yield in case of spray drying by diminishing material deposition on the wall of the drying chamber. The resulting gelatin-free and gelatin-containing powders carried polyphenols in amount ~190 and 53-75 mg gallic acid equivalents GAE/g of powder, respectively. Microwave-assisted extract formulation distinguished from others by higher content of polyphenols, proteins and sugars, higher bulk density and lower solubility. The type of the drying process affected mainly position of the gelatin-derived -OH and amide bands in FTIR spectra. Spray dried formulations compared to freeze dried expressed higher thermal stability as confirmed by differential scanning calorimetry analysis and higher diffusion coefficient; the last feature can be associated with the lower specific surface area of irregularly shaped freeze-dried particles (151-223 µm) compared to small microspheres (~8 µm) in spray-dried powder.Preprint: [10.20944/preprints202105.0358.v1

Freeze vs. Spray Drying for Dry Wild Thyme (Thymus serpyllum L.) Extract Formulations: The Impact of Gelatin as a Coating Material

Freeze drying was compared with spray drying regarding feasibility to process wild thyme drugs in order to obtain dry formulations at laboratory scale starting from liquid extracts produced by different extraction methods: maceration and heat-, ultrasound-, and microwave-assisted extractions. Higher total powder yield (based on the dry weight prior to extraction) was achieved by freeze than spray drying and lower loss of total polyphenol content (TPC) and total flavonoid content (TFC) due to the drying process. Gelatin as a coating agent (5% w/w) provided better TPC recovery by 70% in case of lyophilization and higher total powder yield in case of spray drying by diminishing material deposition on the wall of the drying chamber. The resulting gelatin-free and gelatin-containing powders carried polyphenols in amount ~190 and 53-75 mg gallic acid equivalents GAE/g of powder, respectively. Microwave-assisted extract formulation was distinguished from the others by a higher content of polyphenols, proteins and sugars, higher bulk density and lower solubility. The type of the drying process mainly affected the position of the gelatin-derived -OH and amide bands in FTIR spectra. Spray-dried formulations compared to freeze-dried expressed higher thermal stability as confirmed by differential scanning calorimetry analysis and a higher diffusion coefficient; the last feature can be associated with the lower specific surface area of irregularly shaped freeze-dried particles (151-223 µm) compared to small microspheres (~8 µm) in spray-dried powder

Immobilized yeast cells and secondary metabolites

The use of immobilized cell technology (ICT) is viewed as a promising biotechnological tool to achieve high volumetric productivities of yeast fermentation in bioindustry of alcoholic beverages. During this process a huge number of organic compounds are being formed as yeast secondary metabolites, among which volatile compounds, such as higher alcohols, esters, and vicinal diketones, are the most important flavoring compounds. The objective of this chapter is to summarize the knowledge on the origin of the flavor-active and nonvolatile compounds synthesized by yeast and to describe how the composition of the medium, culture strain, process conditions (temperature, aeration, etc.), bioreactor design, and other critical parameters influence the metabolic activities of yeast cultures. Despite the technological and economic advantages provided by ICT, commercialization of this technology experienced only limited success, mainly due to unpredictable effect of immobilization on yeast physiology. This chapter is an attempt to rationalize and make some conclusions about the impact of cell immobilization on yeast metabolism collected from empirical experiences in production of alcoholic beverages. The knowledge addressing this issue may be of particular benefit to the nascent bioflavor industry

DRYING OF IMMOBILIZED YEAST CELLS IN A SPOUTED BED DRYER WITH

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