Browsing by Author "Scepankova, Hana"
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- Conventional and emergent technologies for honey processing: A perspective on microbiological safety, bioactivity, and qualityPublication . Scepankova, Hana; Pinto, Carlos A.; Paula, Vanessa B.; Estevinho, Leticia M.; Saraiva, Jorge A.Honey is a natural food of worldwide economic importance. Over the last decades, its potential for food, medical, cosmetical, and biotechnological applications has been widely explored. One of the major safety issues regarding such applications is its susceptibility to being contaminated with bacterial and fungi spores, including pathogenic ones, which may impose a hurdle to its consumption in a raw state. Another factor that makes this product particularly challenging relies on its high sugar content, which will lead to the formation of hydroxymethylfurfural (HMF) when heated (due to Maillard reactions). Moreover, honey’s bioactivity is known to be affected when it goes through thermal processing due to its unstable and thermolabile components. Therefore, proper food processing methodologies are of utmost importance not only to ensure honey safety but also to provide a high-quality product with low content of HMF and preserved biological properties. As so, emerging food processing technologies have been employed to improve the safety and quality of raw honey, allowing, for example, to reduce/avoid the exposure time to high processing temperatures, with consequent impact on the formation of HMF. This review aims to gather the literature available regarding the use of conventional and emergent food processing technologies (both thermal and nonthermal food processing technologies) for honey decontamination, preservation/enhancement of honey biological activity, as well as the sensorial attributes.
- Effect of high pressure and temperature on the physicochemical properties of heather honeyPublication . Scepankova, Hana; Saraiva, Jorge A.; Estevinho, Leticia M.Honey is natural sweet substance produced by Apis mellifera, which is consumed as a high nutritive value food. The physicochemical quality criteria of honey are well specified by the European Legislation (EC Directive 2001/110) [1]. The quality properties of honey can be diminished by the influence of heating in the thermal pasteurization of honey [2]. As an alternative to conventional thermal pasteurization, the non-thermal high pressure processing has potential to produce safety food with similar characteristics to the raw unprocessed foods [3]. Therefore, the purpose of this work was to study the effect of three treatments: 1) high pressure (725 MPa for 10 minutes); 2) high pressure with temperature (725 MPa for 10 minutes at temperature of 50 °C); and 3) thermal treatment (75 °C for 5 minutes) on the physicochemical parameters (moisture, pH, electrical conductivity, free acidity, diastase activity and hydroxymethylfurfural content) of a Portuguese heather honey. The results obtained for several physicochemical parameters were significantly different among the samples under the different treatments, for instance, the HMF content. This parameter, widely recognized as indicator of honeys’ freshness [4], depends on several factors, such as temperature, time of heating and storage conditions [5]. The value of HMF in the raw honey was 5,5 ± 0,5 mg.kg−1 of honey (EU limit is 40 mg·kg−1), ensuring that it was a fresh product that has not been subjected to heating or inadequate storing conditions. Concerning the treatments, the ANOVA results showed that the amounts of HMF did differ significantly (P-value= 0.0315). The thermal treatment significantly increased the HMF concentration comparing with the raw honey (P-value= 0.0355). The preliminary results did not show significant increase in the HMF content when high pressure processing, with and without temperature, were applied. Further studies should be performed to confirm that high pressure processing has no adverse effect on the honey quality.
- Enhancement of Bioactivity of Natural Extracts by Non-Thermal High Hydrostatic Pressure ExtractionPublication . Scepankova, Hana; Martins, Margarida; Estevinho, Leticia M.; Delgadillo, Ivonne; Saraiva, Jorge A.Natural extracts, likethose obtained from medicinal herbs, dietary plantsand fruitsare being recognized as important sources of bioactive compounds with several functionalities including antioxidant, anticancer, and antimicrobial activities. Plant extracts rich in phenolic antioxidants are currently being successfully used for several pharmaceutical applications and in the development of new foods(i.e.,functional foods),in order to enhance the bioactivity of the products and to replace synthetic antioxidants.The extraction method applied in the recovery of the bioactive compounds from natural materials is a key factor to enhance the bioactivity of the extracts. However, most of the extraction techniques have to employ heat, which can easily lead to heat sensitive compounds losing their biological activity, due to changes caused by temperature. Presently, high hydrostatic pressure (HHP)is being increasingly explored as a cold extraction method of bioactive compounds from natural sources.This non-thermal high hydrostatic pressure extraction (HHPE) technique allows one to reduce the extraction time and increase the extraction of natural beneficial ingredients, in terms of nutritional value and biological activities and thus enhance the bioactivity of the extracts.This review provides an updated and comprehensive overview on the extraction efficiency of HHPE for the production of natural extracts with enhanced bioactivity,based on the extraction yield,total content and individual composition of bioactive compounds, extraction selectivity, and biological activities of the different plant extracts, so far studied by extraction with this technique.
- High hydrostatic pressure in the modulation of enzymatic and organocatalysis and life under pressure: a reviewPublication . Scepankova, Hana; Galante, Diogo; Espinoza-Suarez, Edelman; Pinto, Carlos A.; Estevinho, Leticia M.; Saraiva, Jorge A.The interest in high hydrostatic pressure (HHP) is mostly focused on the inactivation of deleterious enzymes, considering the quality-related issues associated with enzymes in foods. However, more recently, HHP has been increasingly studied for several biotechnological applications, including the possibility of carrying out enzyme-catalyzed reactions under high pressure. This review aims to comprehensively present and discuss the effects of HHP on the kinetic catalytic action of enzymes and the equilibrium of the reaction when enzymatic reactions take place under pressure. Each enzyme can respond differently to high pressure, mainly depending on the pressure range and temperature applied. In some cases, the enzymatic reaction remains significantly active at high pressure and temperature, while at ambient pressure it is already inactivated or possesses minor activity. Furthermore, the effect of temperature and pressure on the enzymatic activity indicated a faster decrease in activity when elevated pressure is applied. For most cases, the product concentration at equilibrium under pressure increased; however, in some cases, hydrolysis was preferred over synthesis when pressure increased. The compiled evidence of the effect of high pressure on enzymatic activity indicates that pressure is an effective reaction parameter and that its application for enzyme catalysis is promising.
- High-pressure-based strategies for the inactivation of bacillus subtilis endospores in honeyPublication . Scepankova, Hana; Pinto, Carlos A.; Estevinho, Leticia M.; Saraiva, Jorge A.Honey is a value-added product rich in several types of phenolic compounds, enzymes, and sugars recently explored in biomedical and food applications. Nevertheless, even though it has a low water activity (aW = 0.65) that hinders the development of pathogenic and spoilage microorganisms, it is still prone to contamination by pathogenic microorganisms (vegetative and spores) and may constitute harm to special groups, particularly by immunosuppressed people and pregnant women. Thus, an efficient processing methodology needs to be followed to ensure microbial safety while avoiding 5-hydroxymethylfurfural (HMF) formation and browning reactions, with a consequent loss of biological value. In this paper, both thermal (pressure-assisted thermal processing, PATP) and nonthermal high-pressure processing (HPP), and another pressure-based methodology (hyperbaric storage, HS) were used to ascertain their potential to inactivate Bacillus subtilis endospores in honey and to study the influence of aW on the inactivation on this endospore. The results showed that PATP at 600 MPa/15 min/75 C of diluted honey (52.9 Brix) with increased aW (0.85 compared to 0.55, the usual honey aW) allowed for inactivating of at least 4.0 log units of B. subtilis spores (to below detection limits), while HS and HPP caused neither the germination nor inactivated spores (i.e., there was neither a loss of endospore resistance after heat shock nor endospore inactivation as a consequence of the storage methodology). PATP of undiluted honey even at harsh processing conditions (600 MPa/15 min/85 C) did not impact the spore load. The results for diluted honey open the possibility of its decontamination by spores’ inactivation for medical and pharmaceutical applications.
- Honey health benefits and uses in medicinePublication . Scepankova, Hana; Saraiva, Jorge A.; Estevinho, Leticia M.The generation of reactive oxygen species (ROS) and other free radicals during metabolism is an essential and normal process that ideally is compensated through the antioxidant system. However, due to many environmental, lifestyle, and pathological situations, free radicals and oxidants can be produced in excess, resulting in oxidative damage of biomolecules (e.g., lipids, proteins, and DNA). This plays a major role in the development of chronic and degenerative illness such as cancer, autoimmune disorders, aging, cataract, rheumatoid arthritis, cardiovascular, and neurodegenerative diseases (Pham-Huy et al. 2008; Willcox et al. 2004). The human body has several mechanisms to counteract oxidative stress by producing antioxidants, which are either naturally synthetized in situ, or externally supplied through foods, and/or supplements (Pham-Huy et al. 2008).
- Modulation of lipid profile and lipoprotein subfractions in overweight/obese women at risk of cardiovascular diseases through the consumption of apple/berry juicePublication . Habanova, Marta; Holovicova, Maria; Scepankova, Hana; Lorkova, Marta; Gazo, Joaquin; Gazarova, Martina; Pinto, Carlos A.; Saraiva, Jorge A.; Estevinho, Leticia M.Polyphenol-rich foods protect the cellular systems of the human body from oxidative damage, thereby reducing the risk of chronic diseases such as cardiovascular disease (CVD). We investigated the effect of phenolic-rich apple/berry juice (chokeberry, blueberry, and cranberry) on lipidemic profiles in overweight/obese women. The 6 week single-arm pre–post intervention study involved 20 women (mean age 52.95 ± 5.8 years, body mass index ≥25 kg/m2, and ≥1 CVD risk factors) consuming 300 mL/day of the apple/berry juice. Lipid profile, low-density lipoprotein (LDL) subfractions assessed using Lipoprint® electrophoresis, and other parameters related to cardiovascular risk (C-reactive protein, glucose, blood pressure) were analyzed before and again after the intervention in the monitored group of women. High-density lipoprotein cholesterol (HDL-C) increased from 1.30 ± 0.29 to 1.55 ± 0.32, magnesium from 0.85 ± 0.03 to 0.90 ± 0.05, and total antioxidant status from 1.68 ± 0.08 to 1.81 ± 0.10. The LDL/HDL ratio significantly decreased from 3.40 ± 0.99 to 2.66 ± 0.63 mmol/L, and the glucose from 5.50 ± 0.72 to 5.24 ± 0.74 mmol/L. However, the hs-CRP did not change significantly. Women with atherogenic subfractions LDL3-7 at baseline (n = 6) showed a significant reduction from 0.45 ± 0.19 to 0.09 ± 0.07 mmol/L. Overweight/obese women may benefit from apple/berry juice as part of a healthy lifestyle to improve their lipid profile, and thus, contribute to cardiovascular health.
- Quantifying the Impact of High‐Pressure Processing on the Phenolic Profile, Antioxidant Activity, and Pollen Morphology in HoneyPublication . Scepankova, Hana; Majtan, Juraj; Pospiech, Matej; Moreira, Manuela M.; Pinto, Carlos A.; Dias, Luís G.; Estevinho, Letícia M.; Delerue‐Matos, Cristina; Saraiva, Jorge A.Honey can benefit from non‐thermal processing techniques such as high‐pressure processing (HPP) to improve its quality and bioactivity. This study investigated the impact of HPP (600 MPa for 5, 10, and 15 min) on honey's quality, including the levels of hydroxymethylfurfural (HMF), antioxidant activity, total phenolic content (TPC), and phenolic profile. HPP treatment did not significantly affect HMF or TPC levels but led to selective changes in the phenolic profile. Despite a reduction in certain phenolic compound content, HPP for 5 and 15 min caused a significant increase in the antioxidant activity (2,2‐diphenyl‐1‐picrylhydrazyl [DPPH]) of honey from the mean value of 41.8% to values of 45.4% and 49.6%, respectively. On the other hand, HPP for 10 min did not change the antioxidant activity of tested honey. A 27.5% reduction in the equatorial diameter of pollen grains was observed after HPP combined with temperature at 75°C, suggesting an improved release of bioactive compounds. The content of specific phenolic compounds, including caffeic acid, p‐coumaric acid, sinapic acid, naringin, kaempferol, and the TPC, significantly affected the DPPH activity. The increment in the antioxidant activity of HPP honey may be attributed to selective changes in the content of certain phenolic compounds and improved their extraction from pollen grains.
- Study of high pressure and temperature effects on heather honey during storage: Electronic tongue and physicochemical propertiesPublication . Scepankova, Hana; Paula, Vanessa B.; Estevinho, Leticia M.; Dias, L.G.; Saraiva, Jorge A.Honey is a natural sweet substance produced by Apis mellifera, which has great potential to serve as a natural food antioxidant. The physicochemical quality criteria of honey are well specified by the European Legislation (EC Directive 2001/110). The quality properties of honey can be diminished by the influence of heating. As an alternative to the conventional thermal pasteurization, nonthermal high pressure processing (HPP) has potential to produce safe food with similar characteristics to the raw unprocessed foods. The aim of this study was to investigate the effect of HPP (725 MPa for 10 minutes) and HPP with temperature (725 MPa for 10 minutes at 50 °C) on physicochemical properties (moisture, pH, electrical conductivity, free acidity, diastase activity and hydroxymethylfurfural content) of a heather honey in comparison with thermal treatment (75 °C for 5 minutes) and unprocessed honey. The effect of storage (6 months) in processed and unprocessed samples was also investigated. The results showed significant differences in some physicochemical parameters, for instance, the hydroxymethylfurfural content, an indicator of honeys' freshness that depends on several factors, such as temperature, time of heating and storage conditions. An electronic tongue (ET) with lipidic membranes was used to evaluate the differences between all honey groups. A linear discriminant analysis to the ET results showed that the processed and unprocessed honey samples at day 0 (when treatments were applied) and after the storage have matrix differences that allows a complete separation of groups. The correlation between physicochemical and electronic tongue data showed the advantages of this data fusion.
- The High Pressure Preservation of Honey: A Comparative Study on Quality Changes during StoragePublication . Scepankova, Hana; Majtan, Juraj; Estevinho, Leticia M.; Saraiva, Jorge A.In commercially available honey, the application of a heat treatment to prevent spoilage can potentially compromise its beneficial properties and quality, and these effects worsen with extended storage. The high-pressure processing (HPP) of honey is being explored, but its long-term impact on honey quality has not been characterised yet. This study evaluated the effects of HPP and thermal processing on the microbial load, physicochemical quality (i.e., hydroxymethylfurfural content and diastase activity), and antioxidant capacity of honey after treatment and following extended storage (6, 12, and 24 months) at 20 degree celsius. Pasteurization (78 degree celsius/6 min) effectively eliminated the microorganisms in honey but compromised its physicochemical quality and antioxidant activity. HPP initially showed sublethal inactivation, but storage accelerated the decrease in yeasts/moulds and aerobic mesophiles in honey (being <1 log CFU/g after 24 months of storage) compared to unprocessed honey and honey thermally treated under mild conditions (55 degree celsius/15 min). The physicochemical characteristics of the quality of HPP-treated honey and raw unprocessed honey did change after long-term storage (24 months) but remained within regulatory standards. In conclusion, HPP emerged as a more suitable and safe preservation method for Apis mellifera honey, with a minimal risk of a loss of antioxidant activity compared to traditional industrial honey pasteurization.