Quality differences of hamburger patties incorporated with encapsulated β carotene both as an additive and edible coating

In this study, different formulations of chitosan (CS) and chitosan/sodium tripolyphosphate (CS/TPP) matrix solutions including β carotene were used as additives and edible coatings in hamburger patties, and the treatments were compared to control in terms of quality, oxidative and microbiological features of the patties. TBARS (2‐thiobarbituric acid reactive substances) values of almost all the treatments increased throughout storage at 4 °C for 8 days. (p < .05). On the last day of storage, the treatment including 5% CS/TPP with β carotene and all the coated treatments had lower TBARS values than the other treatments (p < .05). The comparison of different treatments including the solutions of chitosan or chitosan/TPP matrix containing β carotene showed that incorporation of solution as an edible coating was more effective in lipid oxidation and microbial growth than its utilization as an additive on quality of patties according to the results on last day of storage.

Practical applications

Using polymers loaded with antioxidant agents as additives or edible coatings in food products is one of the most popular scientific approaches in recent studies. In this study, hamburger patties were incorporated with chitosan/sodium tripolyphosphate (CS/TPP) matrix solution loaded with β carotene, CS/TPP matrix solution, pure chitosan solution and pure β carotene as additives and/or edible coatings. By this way, synergistic effects of β carotene with different formulations of chitosan (CS) and CS/TPP were also tested. The results showed that lipid oxidation and microbial growth in the coated patties were mostly lower than that of the other patties formulated with different additives on the last day of storage.     

植物源食品中α-胡萝卜素和β-胡萝卜素的测定及比较分析

采用高效液相色谱法建立植物源食品中α-胡萝卜素和β-胡萝卜素同时在线分析检测技术,并以胡萝卜冻干粉为样品进行方法学验证。结果显示,α-胡萝卜素和β-胡萝卜素分别在0.8~20、0.4~8.2μg/m L范围内线性良好,精密度的相对标准偏差分别为4.45%、4.71%,加标回收率分别为96%~112%、83.5%~103%,加标回收率的相对标准偏差分别为2.67%~5.83%、4.90%~7.42%,以上结果说明该方法重复性良好、准确可行。采用该方法测定了多种植物源食品的胡萝卜素含量并进行比较分析,大多数样品中β-胡萝卜素含量高于α-胡萝卜素,只有南瓜中所含的α-胡萝卜素高于β-胡萝卜素。     

Constitutive Effects of Lead on Aryl Hydrocarbon Receptor Gene Battery and Protection by β‐carotene and Ascorbic Acid in Human HepG2 Cells

Lead (Pb) is an environmental pollutant that can get entry into human body through contaminated foods, drinks, and inhaled air leading to severe biological consequences, and has been responsible for many deaths worldwide. The objectives of this study were 1st to investigate the modulatory effects of environmentally relevant concentrations of Pb on AhR gene battery, which is controlling xenobiotics metabolism. 2nd, trials to reduce Pb‐induced adverse effects were done using some phytochemicals like β‐carotene or ascorbic acid. Human hepatoma (HepG2) cell lines were exposed to a wide range of Pb concentrations varying from physiological to toxic levels (0 to 10 mg/L) for 24 h. High Pb concentrations (1 to 10 mg/L) significantly reduced phase I (CYP1A1 and 1A2) and phase II (UGT1A6 and NQO1) xenobiotic metabolizing enzyme mRNA expression in a mechanistic manner through the AhR regulation pathway. Additionally, these Pb concentrations induced oxidative stress in HepG2 cells in terms of production of reactive oxygen species (ROS) and induced heme oxygenase‐1 mRNA expression in a concentration‐dependent phenomenon. Coexposure of HepG2 cells to physiological concentrations of some micronutrients, like β‐carotene (10 μM) or ascorbic acid (0.1 mM), along with Pb (1 mg/L) for 24 h significantly reduced the levels of ROS production and recovered AhR mRNA expression into the normal levels. Thus, consumption of foods rich in these micronutrients may help to reduce the adverse effects of lead in areas with high levels of pollution.     

Changes in bioactive compounds and antioxidant activity during convective drying of murta (Ugni molinae T.) berries

Murta (Ugni molinae T.) berries were air‐dried at five temperatures (40, 50, 60, 70 and 80 °C), and the changes in β‐carotene, phenolic acids, total phenolic and flavonoid contents and antioxidant capacities (DPPH and ORAC) were investigated. The berries showed a high content of β‐carotene, which decreased during drying temperature between 40 °C and 80 °C. Free and bound phenolic acids were also determined, showing gallic acid to be the prevalent phenolic acid. Total phenolic and flavonoid contents in the dried berries showed a higher decrease at lower temperature due to longer drying time. The radical‐scavenging activity also showed higher antioxidant activity at higher drying temperatures (70–80 °C) than at lower drying temperatures (40–50 °C). Total phenolic content (TPC) and flavonoids showed good correlation with antioxidant capacity. Murta berries proved to be an excellent source of antioxidants and bioactive compounds and are therefore a potential ingredient for new functional food products.     

Bioactive components,ABTS radical scavenging capacity and physical stability of orange,yellow and purple sweet potato (Ipomoea batatas) powder processed by convection‐ or vacuum‐drying methods

This study aims to investigate the antioxidant properties and physical stability of convection‐ or vacuum‐dried orange, yellow and purple sweet potato (Ipomoea batatas) powder upon room temperature storage at different relative humidity (RH) of 33%, 43%, 54% and 75% for 25 days. Both convection and vacuum‐dried samples had lower total phenolic content (TPC), anthocyanin content and antioxidant activity compared to the fresh samples. Vacuum‐dried powder retained higher antioxidant activity than convection‐dried powder. Storage of the powder at high RH of 75% resulted in apparent clump formation, which was likely attributed to the decrease of glass transition temperature (T_g). In general, purple sweet potato powder contained the highest TPC (255.0 mg GAE 100 g DW^?1) and antioxidant activity (1924.0 μmol TEAC 100 g DW^?1), while orange powder had the highest beta‐carotene content (127.2 mg 100 g DW^?1). Vacuum‐dried sweet potato powder, which has relatively higher antioxidant activity, could be a potential functional ingredient or natural colourant for the food industry.     

In vitro β‐Carotene Bioaccessibility and Lipid Digestion in Emulsions: Influence of Pectin Type and Degree of Methyl‐Esterification

Citrus pectin (CP) and sugar beet pectin (SBP) were demethoxylated and fully characterized in terms of pectin properties in order to investigate the influence of the pectin degree of methyl‐esterification (DM) and the pectin type on the in vitro β‐carotene bioaccessibility and lipid digestion in emulsions. For the CP based emulsions containing β‐carotene enriched oil, water and pectin, the β‐carotene bioaccessibility, and lipid digestion were higher in the emulsions with pectin with a higher DM (57%; “CP57 emulsion”) compared to the emulsions with pectin with a lower DM (30%; “CP30 emulsion”) showing that the DM plays an important role. In contrast, in SBP‐based emulsions, nor β‐carotene bioaccessibility nor lipid digestion were dependent on pectin DM. Probably here, other pectin properties are more important factors. It was observed that β‐carotene bioaccessibility and lipid digestion were lower in the CP30 emulsion in comparison with the CP57, SBP32, and SBP58 emulsions. However, the β‐carotene bioaccessibility of CP57 emulsion was similar to that of the SBP emulsions, whereas the lipid digestion was not. It seems that pectin type and pectin DM (in case of CP) are determining which components can be incorporated into micelles. Because carotenoids and lipids have different structures and polarities, their incorporation may be different. This knowledge can be used to engineer targeted (digestive) functionalities in food products. If both high β‐carotene bioaccessibility and high lipid digestion are targeted, SBP emulsions are the best options. The CP57 emulsion can be chosen if high β‐carotene bioaccessibility but lower lipid digestion is desired.