Whole Wheat Crackers Fortified with Mixed Shrimp Oil and Tea Seed Oil Microcapsules Prepared from Mung Bean Protein Isolate and Sodium Alginate

Shrimp oil (SO) rich in n-3 fatty acids and astaxanthin, mixed with antioxidant-rich tea seed oil (TSO), was microencapsulated using mung bean protein isolate and sodium alginate and fortified into whole wheat crackers. SO and TSO mixed in equal proportions were emulsified in a solution containing mung bean protein isolate (MBPI) and sodium alginate (SA) at varied ratios. The emulsions were spray-dried to entrap SO-TSO in MBPI-SA microcapsules. MBPI-SA microcapsules loaded with SO-TSO showed low to moderately high encapsulation efficiencies (EE) of 32.26–72.09% and had a fair flowability index. Two selected microcapsules with high EE possessed the particle sizes of 1.592 and 1.796 µm with moderate PDI of 0.372 and 0.403, respectively. Zeta potential values were −54.81 mV and −53.41 mV. Scanning electron microscopic (SEM) images indicated that microcapsules were spherical in shape with some shrinkage on the surface and aggregation took place to some extent. Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC) analyses of samples empirically validated the presence of SO-TSO in the microcapsules. Encapsulated SO-TSO showed superior oxidative stability and retention of polyunsaturated fatty acids (PUFAs) to unencapsulated counterparts during storage of 6 weeks. When SO-TSO microcapsules were fortified in whole wheat crackers at varying levels (0–10%), the crackers showed sensorial acceptability with no perceivable fishy odor. Thus, microencapsulation of SO-TSO using MBPI-SA as wall materials could be used as an alternative carrier system, in which microcapsules loaded with PUFAs could be fortified in a wide range of foods.

Effect of process parameters on the antioxidant activity of Vietnamese tea (Camellia sinensis O. Kuntze) seed oil

This research was carried out on Tea (Camellia sinensisO. Kuntze.) seeds (containing 22.01% oil) harvested from Trung du tea trees varieties, cultivated in Phu Tho, Vietnam to select the most suitable processing methods which enhance the high antioxidant activity of the oil in the seed oil extraction. The objective of this research is to study the effects of particle size, material/solvent ratio, temperature, time, speed of solvent movement, and extraction cycle on antioxidant properties of the oil (by analysing IC50, total polyphenol content, total carotenoid, and total tocopherol value). The suitable extraction conditions were determined as follows: particle size was 0.25-0.5 mm, the solid-solvent ratio was 1/8-1/10, the extraction temperature was 35-45oC, the extraction time was 7-9h, speed of solvent movement was 200-250 r/m and the extraction cycle was two times. The tea seed oil extracted under the suitable conditions had the DPPH radical scavenging activity (IC50), total polyphenol content, total carotene, and total tocopherol of 62.19 mg/ml, 4.45 mgGAE/g dry weight, 89 mg/kg, and 710 mg/kg, respectively. The high content of antioxidants makes tea seed oil has a good antioxidant capacity, high oxidation stability, and relatively long shelf life. Therefore, research on using wasted tea seed sources to extract oil has great potential for the vegetable oil industry and a high potential of application in food technology.

Investigating the Potential of Vietnamese Tea Seed Oil (Camellia sinensis O.Kuntze) for the Enhancement of Oxidative Stability in Vegetable Oils

This study examined the effectiveness of different antioxidative compounds, namely 0.2% BHA (Butylated hydroxyanisole) + BHT (butylated hydroxytoluene), 0.03% α – tocopherol, and 3% and 6% tea seed oil (TSO) on the oxidative stability of vegetable oils. Four commonly used oils, viz. rapeseed oil (RSO), peanut oil (PNO), sunflower oil (SFO), and soybean oil (SBO), were assessed by the Schall Oven test method and monitored during the 12-day preservation period under 60°C. The total oxidation values (TOTOX) of the samples treated with 6% TSO were lower than those treated with 0.2% BHA+BHT. The results indicated the potential of TSO as a novel natural antioxidant for dietary vegetable oils. Our study also suggested that TSO could serve as an effective substitution for currently used synthetic antioxidants such as BHA and BHT.

Thermal Degradation of Natural Rubber Vulcanizates Reinforced with Organomodified Kaolin Intercalates

In this study, Natural Rubber Vulcanizates (NRV) reinforced with organomodified kaolin was developed. The NRV were subjected to thermal degradation to ascertain its suitability for high-temperature automotive applications. Kaolin intercalation was achieved using derivatives of Rubber seed oil (Hevea brasiliensis) and Tea seed oil (Camellia sinensis) in the presence of hydrazine hydrate as co-intercalate. The developed Natural Rubber Vulcanizates were characterised using Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) Spectroscopy and Scanning Electron Microscopy (SEM). FTIR spectra obtained for the organomodified natural rubber vulcanizates revealed the presence of carbonyl groups at bands 1564cm-1 and 1553cm-1 which is an indication of organomodified kaolin intercalation within the Natural Rubber matrix for kaolin intercalates of Rubber seed oil and Tea seed oil respectively while no value was reported for the Natural Rubber vulcanizates obtained from the pristine kaolin filler. TGA results indicated that NRV developed from kaolin intercalates of Rubber seed oil (RSO) with onset degradation and final degradation temperatures of 354.2°C and 601.3°C were found to be the most thermally stable of the Natural Rubber Vulcanizates investigated. The SEM micrograph revealed that the kaolin nanofillers in Rubber Seed Oil modified Natural Rubber Vulcanizates were well dispersed as compared to that of Tea Seed Oil modified Natural Rubber Vulcanizates.