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Abstract
In this study, it is aimed to encapsulate some functional components of the olive leaves. Olive leaf extract was encapsulated using solution of sodium alginate, sodium alginate/gelatine, and sodium alginate/agar as wall material by ionic gelation technique. Also, olive leaf extract was encapsulated using solution of gelatine as wall material by cold gelation technique. The viscosities of the coating materials used in the study were investigated. An optimisation process was carried out to determine the injection time to be applied in the ionic gelation technique and the encapsulation efficiencies, particle sizes, swelling ratios, in vitro release profiles, and antioxidant activities of the obtained capsules were determined. While the encapsulation efficiency of the capsules obtained by the cold gelation technique was determined as the highest (98.2 ± 0.99%), it was revealed that the viscosity of the wall material used in the ionic gelation technique was important in the encapsulation efficiency. The particle size and swelling rate of the capsules obtained using the cold gelation technique were the highest. The release rate of oleuropein was generally higher at gastric pH than at intestinal pH. A correlation was found between antioxidant activities and the encapsulation efficiency of capsules.
Abstract
A large amount of waste, especially the outer part of citrus fruits (peel), is generated after consuming the pulp and it remains unused. The valorisation of this waste by recovering its bioactive compounds seems interesting. The aim of this study was to find the optimal conditions using ultrasound-assisted extraction (UAE) that yield the highest carotenoid content and better antioxidant activity from Citrus reticulata Blanco peels.
Response surface methodology (RSM) through Box–Behnken experimental design was used to optimise the conditions for carotenoid extraction using UAE. Hexane concentration, temperature, and sonication time were selected as the main factors.
The results revealed that all independent variables affected the responses. The optimal UAE conditions for hexane concentration, temperature, and sonication time were 60.76%, 36.45 °C, and 37.32 min, respectively. The values of total carotenoid content (TCC) and total antioxidant activity (TAA) obtained by UAE were higher than those obtained by the maceration extraction method.
It can be concluded that the medium and extraction parameters, including hexane concentration, temperature, and sonication time, significantly influenced the recovery of carotenoids and antioxidant activity. The optimisation study allowed determining the appropriate conditions to maximise both responses. Compared to conventional maceration, the UAE method was superior and more efficient for extracting carotenoids from C. reticulata Blanco peels.
Abstract
Food allergies became a major public health and food safety interest in the past decades as their prevalence is increasing, and their only available treatment is a strict elimination diet that necessitates appropriate food labelling regulations. While such regulations are available worldwide, most of them are not taking into account inadvertent allergen cross-contamination and they usually do not define threshold doses that could support the industry in their endeavour to provide reliable food labels for allergic consumers. This resulted in the proliferation of the “may contain” type precautionary allergen labelling (PAL), which is voluntary and is intended to warn consumers for potential unintended contamination with an otherwise undeclared allergen. As this kind of labelling is hardly ever based on actual risk assessment, it puts both the industry and the consumer into a difficult position. A promising tool towards the solution of this problem could be allergen threshold doses based on clinical data, which are becoming increasingly available. This review intends to present this process, the new ways of improved risk assessment it opens, and its implications for food analysis.
Abstract
The aim of this study was to evaluate the possibility of storage of mangoes (Mangifera indica L.) coated with chitosan-based nano-silver films. Chitosan-based nano-silver films were first made using chitosan with three degrees of deacetylation of 70, 80, and 90%. The films were then used for coating the mango fruits. All coated mangoes and the control samples were stored at 12 °C in a cooling room. The respiration rate, ethylene production rate, weight loss, firmness, total soluble solids, total acid, vitamin C, total sugar, and change of peel colour were evaluated once every 5 days during the storage period. As observed, the coating using the chitosan-based nano-silver films did not induce significant negative alterations on most of the physical characteristics and chemical constituents of the fruits. In addition, the coating using those materials helped reduce the respiration and the ethylene gas production and retard the ripening process of mango fruits. The chitosan-based films with higher deacetylation degrees (CN80 and CN90) better moderated the respiration of mangoes. The coating using chitosan-based nano-silver films prolonged the shelf-life of mangoes (up to 35 days) compared to the control (less than 10 days).
Abstract
The aim of this study was to isolate lactic acid bacteria (LAB) from artisanal cheeses and evaluate their probiotic potential and antibiotic susceptibility under in vitro conditions. Cheeses obtained at different maturation times were analysed for moisture and lipid contents, as well as for the presence of various microorganisms, including coagulase positive staphylococci, Salmonella spp., Escherichia coli, Listeria monocytogenes, filamentous fungi, yeasts, total mesophilic bacteria, and LAB. After identification, the selected LAB were subjected to human gastrointestinal tract (HGT) conditions to evaluate their survival rates. Of the 18 Lactobacillus strains isolated, 11 survived the HGT test and presented γ-haemolysis. No resistance was observed against antibiotics. Lactobacillus fermentum C1a, C1b, C1c, and C1f, as well as Lactobacillus paracasei C1d, C1e, and C1g, were identified as potential starter cultures for the food industry.
Abstract
Obesity and other unhealthy behaviors are behind cardiovascular morbidity and mortality, with the Roma population particularly at risk. The aim of our cross-sectional (questionnaire- and physical measurements-based) study was to compare the prevalence of obesity in Hungarian, Romanian, and Slovakian Hungarian-speaking Roma and non-Roma (N = 1893) in relation to lifestyle-related risk factors for cardiovascular diseases (CVD). In the total sample, the proportion of extreme obesity was higher in Roma (P < 0.001) than non-Roma. The mean waist circumference was the highest in Hungary (P < 0.001). Visceral fat was higher in the Hungarian Roma sample than in the Slovak (P = 0.006) or Romanian Roma samples (P = 0.005). Hungarian Roma total cholesterol levels were lower than in the Slovak (P < 0.001) or Romanian samples (P < 0.001). Hypertension and cholesterol levels were associated with a higher risk among non-Roma men (P < 0.001), and the presence of smoking increased CVD risk among both men (P = 0.024) and women (P < 0.001) in the Roma minority. The combined presence of several risk factors was found mainly in Roma. Overall, Roma scores were found to be worse, but ethnicity did not provide clear evidence for the questions examined, but rather the level of education, which is associated with socioeconomic status.
Abstract
Radio frequency (RF) heating of agri-food, especially low moisture viscous sauces (LMVS), have obvious advantages. However, uneven heating is one main problem of RF heating technology that has to be solved. Due to the unclear heating mechanism and the difficulty to measure the three-dimensional temperature distribution in the heated object, computer-aided analysis method was adopted. Based on the RF heating numerical calculation model after experimental verification and the characteristics of polyetherimide (PEI) assisted RF heating of peanut butter (PB), this study proposed an improved method for an existing protocol. Meanwhile, parameters of the new protocol were optimised by the Multi-objective Global Optimisation (MGO) of its surrogate model. Results demonstrated that the best size of PEI block in the new protocol was Φ100 × 9.5 mm and the positional height was 12 mm. When the pasteurisation temperature Tp was set to 70 °C and the control temperature Tc was set to 75 °C, the temperature uniformity evaluation indices, Over-shoot Temperature Control Index (OTCI) and Targeted Penetration Depth (TPD), were 0.920% and 3.975 mm, respectively. Compared with 4.845% and 4.940 mm before improvement, the new protocol achieved significant optimisation and improved the temperature uniformity effectively. This also proved the feasibility of MGO method of surrogate model in relevant studies.
