Poster OER - Ngành Công nghệ thực phẩm
URI vĩnh viễn cho bộ sưu tập này
Duyệt qua
Đang duyệt Poster OER - Ngành Công nghệ thực phẩm theo Tác giả
Đang hiển thị 1 - 5 trong tổng số 5
Kết quả mỗi trang
Tùy chọn sắp xếp
- Tài liệuComparison of Phytochemical Contents, Antioxidant and Antibacterial Activities of Various Solvent Extracts Obtained from ‘Maluma’ Avocado Pulp Powder(Trường Đại học Nguyễn Tất Thành (Công nghệ thực phẩm), 2024) Thi, Van Linh Nguyen; Quoc, Duy Nguyen; Nhu, Ngoc Nguyen; Thi, Thuy Dung NguyenAlthough avocado is a superfood rich in phytochemicals with high antioxidant activities, studies on the antibacterial properties of its pulp are limited, except for seed and peel portions. In this study, three types of solvent (acetone, methanol, and diethyl ether) were used to obtain the extracts from “Maluma” avocado pulp powder prepared by infrared drying. The extracts were analyzed for total polyphenols, phytopigments (total chlorophylls and carotenoids), antioxidant activities (ferric-reducing antioxidant power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl (DPPH), and 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays), and antibacterial activities against seven pathogens (Shigella sonnei ATCC 9290, Escherichia coli ATCC 8739, Salmonella typhi ATCC 6539, Vibrio parahaemolyticus ATCC 17802, Proteus mirabilis ATCC 25933, Staphylococcus aureus ATCC 6538, and Bacillus cereus ATCC 11778). The results showed that the acetone solvent could extract the highest polyphenols and chlorophylls with the highest antioxidant activity in terms of ABTS and DPPH assays. In contrast, diethyl ether exhibited the most significant content of carotenoids and FRAP values. However, the methanol extract was the best solvent, exerting the strongest antibacterial and meaningful antioxidant activities. For the bacterial activities, Gram-positive pathogens (Bacillus cereus and Staphylococcus aureus) were inhibited more efficiently by avocado extracts than Gram-negative bacteria. Therefore, the extracts from avocado powder showed great potential for applications in food processing and preservation, pharmaceuticals, and cosmetics. [5]
- Tài liệuDrying kinetics and changes of total phenolic content, antioxidant activity and color parameters of mango and avocado pulp in refractance window drying(Trường Đại học Nguyễn Tất Thành (Công nghệ Thực phẩm), 2024) Thi, Van Linh Nguyen; Quoc, Duy Nguyen; Phuoc Bao Duy NguyenRefractance window drying is an innovative technology belonging to the fourth generation of drying technologies that could enhance the quality of the dried product and improve the drying process. In this study, two factors with the type of fruit pulps (avocado and mango) and drying temperature (ranging from 80 to 95 ºC) were investigated. Results showed that in refractance window drying, the evaporation process rapidly occurred, mainly in the falling-rate period with undetectable constant-rate period. The Weibull was the best fit model among eight investigated mathematical models that could determine the drying behavior. The effective diffusivity was found to be from 4.25×10-10 m2/s to 7.24×10-10 m2/s for avocado pulp, and from 4.50×10-10 m2/s to 10.67×10-10 m2/s for mango pulp when the drying temperature was changed from 80 to 95 ºC. Moreover, the corresponding activation energy was 32.06 and 66.03 kJ/mol for avocado and mango pulp moisture evaporation, respectively, and the highest quality of powders of both dried pulps was obtained after processing at 90°C. The refractance window drying revealed a high potential in the production of fruit powders from avocado and mango due to the high retention of more than 80% of total phenolic content (TPC) and antioxidant activity. TPC could be used as a useful criterion for the evaluation of the drying process in terms of dried product quality [5]
- Tài liệuEffects of Infrared Drying Conditions and Maltodextrin Addition on Some Physicochemical Characteristics of Avocado (Persea americana) Pulp Powder(Trường Đại học Nguyễn Tất Thành (Công nghệ thực phẩm), 2024) Thi, Van Linh Nguyen; Quoc, Duy Nguyen; Thi, Thuy Dung Nguyen; Phuoc, Bao Duy NguyenIn this study, avocado pulp with a good nutritional profile and economic value was dehydrated using infrared drying to produce pulp powder, which shows potential application in nutritional supplements. An experimental design with two factors, namely maltodextrin level (0% and 9%) and infrared temperature (ranging from 65 to 80 ºC), was used. Responses related to the physicochemical properties of the resulted powder were observed, including peroxide value, total polyphenols, total chlorophylls, antioxidant activity, and color parameters (L*, a*, and b* values). The quality of dried products may be harmed by drying either at a high temperature or for an extended period of time. The coating substance maltodextrin was found to be beneficial in limiting unexpected changes in avocado pulp subjected to infrared drying. The highest quality of dried avocado could be obtained via infrared drying of avocado pulp with 9% maltodextrin at 70 ºC, as illustrated by the exceptional retention of total polyphenols, total chlorophylls, and antioxidant activity, being 95.1, 95.2, and 94.4%, respectively. Moreover, the short drying time (35–55 min) led to the minimization of lipid oxidation and the absence of peroxide compounds in all sample [4]
- Tài liệuKinetic Study on Chlorophyll and Antioxidant Activity from Polyscias fruticosa (L.) Harms Leaves via Microwave- Assisted Extraction(Trường Đại học Nguyễn Tất Thành (Công nghệ Thực phẩm), 2024) Thi, Thuy Dung Nguyen; Quoc, Duy Nguyen; Thi, Van Linh NguyenPolyscias fruticosa (L.) leaves contain significant bioactive compounds with high antioxidant activity such as chlorophylls, total polyphenols, etc. but these have still been underutilized. In this study, the kinetics of chlorophyll and antioxidant activity extraction from P. fruticosa leaves by microwave-assisted extraction (MAE) were investigated. Microwave power was 300, 450, or 600 (W); the ratio of material/solvent varied from 1:40 to 1:80 (g/mL). In this study, the second-order kinetic model successfully predicted the change of chlorophyll and antioxidant activity during MAE. The increase of microwave power or/and the solvent amount increased saturated extraction efficiency and the extraction rate constant. However, the saturated concentration of chlorophyll and antioxidant activity increased with the increment of microwave power and the decrease in solvent amount. [4]
- Tài liệuMicroencapsulation of roselle (Hibiscus sabdariffa L.) anthocyanins: Effects of different carriers on selected physicochemical properties and antioxidant activities of spray-dried and freeze-dried powder(Trường Đại học Nguyễn Tất Thành (Công nghệ thực phẩm), 2024) Quoc, Duy Nguyen; Thanh, Thuy Dang; Thi, Van Linh Nguyen; Thi, Thuy Dung Nguyen; Nhu, Ngoc NguyenAnthocyanins are abundant phytochemicals in nature that draw the public interest not only in their health effects, such as antioxidant, anti-inflammatory and anti-carcinogenic properties. It also showed their function in providing foodstuffs with appealing and distinctive color. In this study, anthocyanins from hibiscus (Hibiscus sabdariffa L.) calyces were microencapsulated by spray drying and freeze drying techniques using a wide variety of carriers including maltodextrin (MD), gum Arabic (GA) and their binary blends with inulin (INU) and konjac glucomannan (KON). The results showed that freeze-dried hibiscus powder using KON as carrier had the highest phenolic, anthocyanin and antioxidant activity, followed by spray-dried and freeze-dried MD/KON samples, which indicated the role of KON in the effective retention of antioxidants during the drying process. In addition, the ferric and cupric ion reduction activity (FRAP and CUPRAC) of the spray- dried samples was significantly higher than those of the freeze-dried powder. However, in terms of encapsulation efficiency (EE) of anthocyanins, KON was shown to be ineffective in entrapping these compounds in microcapsules with the lowest EE of freeze-dried KON and spray-dried MD/KON of 43.6% and 55.4%, respectively. By contrast, MD/GA was the most effective carrier, retaining anthocyanins inside the carrier matrix and limiting their loss to the surface of the microcapsules in both spray-drying and freeze-drying methods (EE of 91.8% and 95.7%, respectively). In addition, the moisture content of spray-dried powder samples was significantly higher than that of lyophilized powders, and the solubility of all samples was above 94.1%. [6]