Journal of Food Science and Technology最新文献

Pile fermentation plays a crucial role in the formation of the unique flavor of Liupao tea, which can effectively reduce the bitterness of the tea and promote the formation of red tea soup. In this study, the non-volatiles changes of Liupao tea during pile fermentation processing were fully analyzed by UPLC-QTOF-MS/MS. A total of 271 metabolites with significant differences were identified in Liupao tea during pile fermentation(P < 0.01, VIP > 1), and their trends were grouped into 10 subclasses by K-means analysis. Three differential metabolites Choline Alfoscerate, N1-Methyl-4-pyridone-5-carboxamide, and 2-Aminovalienone were shared among the three different pile fermentation periods. The results provided valuable information for understanding the dynamic changes of non-volatile substances during the pile fermentation process of Liupao tea.

Despite the remarkably high antioxidant activity of tocopherols, their applications in the food industry are limited because of their instability under various conditions. Complexes of α-tocopherol (α-TQ) or α-tocopheryl acetate (α-TQA) with β-cyclodextrin (β-CD) or starch were prepared and characterized by UV–vis, IR and thermal analysis. Oxidative stability of α-TQ and α-TQA against H₂O₂ was 74.7 and 88.8% respectively (576 h). However, stability increased to 82.9 and 100% for β-CD and 99.2 and 99.4% for starch complexes respectively, which indicates that starch is an excellent stabilizing host in addition to being an economic material. Stability of α-TQ and α-TQA under light conditions was dependent on their physical state; it was 55.3 and 82.9% (oil) but stability was lowered to 19.4 and 76.5% in solution (2.21 mM). In addition, exposure to UV irradiation decreased their stability to 39.2 and 85.0% as oil and 61.2 and 89.1% in solution respectively. However, the stability of all complexes remained > 99.0% under light and UV conditions. Accordingly, α-TQ, the natural and biologically active form, can be used as complex rather than α-TQA often used because of its higher stability. Docking revealed that both forms fit in β-CD with the side chain taking “U” conformation.

Zinc oxide nanoparticles (ZnO-NPs) were green synthesized using Carica papaya peel extract as a reducing agent and used to develop a novel Micro Raman Spectroscopy method to detect melamine in infant milk powder. Citrate was coated on the biosynthesized ZnO-Np, as a melamine-binding agent. SEM, AFM, TEM, FTIR, MRS, and XRD were used to confirm the morphology, size, and nature of ZnO-Np, citrate-coated ZnO-Np (ZnO-W/C), and ZnO-W/C conjugated with melamine. The zeta potential was − 43.5 mV, and the ZnO-W/C particle size ranged from 50 to 100 nm. Using MRS with a laser wavelength of 785 nm for a Raman shift ranging from 400 to 1200 cm⁻¹, ZnO-W/C was utilized to detect melamine. ZnO-W/C conjugated with melamine showed a Raman shift at 677 cm⁻¹. A linear regression model based on the Raman shift at different melamine concentrations was developed to quantify melamine in the spiked milk powder. With spiked infant milk powder, the lowest melamine detection level was 0.125 ppm. This is a sensitive and effective way to detect melamine in infant milk powder. This work suggests that ZnO-NPs, synthesized using fruit industry waste as a starting material, can serve as a diagnostic tool to ensure food safety.

In this study, the changes in the physicochemical properties, color stability, and amino acid composition of cemen paste (CP) produced by adjusting to different pH levels (3.0, 4.0, 5.0, and 6.0) and enriched with different amounts (0%, 3%, 4% and 5%) of encapsulated raspberry powders (ERP) during 120 days of storage at 2.0 ± 0.5 °C were investigated. ERP had an important potential for use as a food ingredient with its bioactive components (total phenolic content (TPC), anthocyanin and ascorbic acid), antioxidant activity and high redness values. Essential and non-essential amino acid composition, moisture content, pH, lightness (L*), redness (a*), yellowness (b*), chroma (C*) and hue angle (^oh) values of cemen pastes (CPs) were significantly (p < 0.01) affected by initial pH of CP (I-pH), ERP levels (ERPL) and storage time (ST) parameters and all possible interactions. The inclusion of ERP contributed to the improvement of CP visual properties and color stability by increasing redness. CPs with lower I-pH values had higher a* values and higher color stability over the storage period. In general, increasing ERPL and decreasing I-pH resulted in decreased amino acid contents of CPs. In conclusion, acidification (3.0, 4.0) of I-pH of CP and using ≥ 4.00% ERP can be recommended as an effective way to provide more stable samples based on color characteristics and amino acid content.

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Catechin hydrate (CH) is a kind of polyphenol present in many plantsincluding green tea, fruits, red wine and cocoa with very good antioxidant effect. The formulation of CH nanoemulsion increased the bioavailability and stability of catechin, allowing for easier food incorporation and faster absorption by the body. The major goal of the current study was to create a nanoemulsion as a reliable delivery mechanism for catechin hydrate and its incorporation into yogurt to increase its antioxidant activity. In this study, ultrasonication method was used for nanoemulsion preparation. The optimized condition for obtaining reduced droplet size includes two-minute ultrasonication time, 40% ultrasonication amplitude and 1.61:1emulsifier to oil ratio. The CH nanoemulsion’s spherical droplet shape was confirmed by transmission electron microscopy(TEM). The chemical characteristics of CH nanoemulsion was studied using FTIR and Raman spectroscopy. The zeta potential value of CH nanoemulsion was-57.56 ± 1.35mV and the size was found to be 78.4 nm.Shelf-life analysis was carried out for yogurt incorporated with CH (YCH) and CH nanoemulsion (YCHN). During shelf-life study, YCHN showed better free radical scavenging activity, stability, and higher sensory assessment than YCH. YCHN had a greater Lactobacillus count (9.3 log CFU/mL) than plain yogurt. Hence, the study suggests catechin hydrate nanoemulsion (YCHN)as an effective technique to reduce bitterness and astringency of catechin for food fortification with better antioxidant activity.

A rapid, simple, and cost-efficient extraction method was developed for evaluating and screening benzo(a)pyrene (BaP) in tea samples by using high performance liquid chromatography (HPLC) with coupled fluorescence detector (FLD) in order to obtain the best extraction performance. In this study, it was observed that when optimized using microwave assisted extraction (MAE) method was performed twice for 2 min using 10 mL n-hexane: acetonitrile (1:3, v/v). The recoveries for BaP in tea were found to be 97 ± 2; 83 ± 8 and 92 ± 6%, respectively. Using classical solid-liquid extraction (CSLE), it was observed that when the extraction procedure was performed twice for 4 min with 10 mL n-hexane: acetonitrile (3:1,v/v). The recoveries for BaP in tea were found to be 104 ± 5; 81 ± 9 and 86 ± 8%, respectively. The levels of BaP in tea were found to change in the range from 0.75 to 0.83 µg kg^-1 (MAE) and 0.72 to 0.86 µg kg^-1 (CSLE). Although the matrix of tea is complex, BaP was detectable without doing any cleaning up procedures.

A huge amount of fruits and vegetables is being produced and processed in India and therefore the waste is also generated in high quantities. These wastes are good sources of vitamins, enzymes, cellulose, and many other essential compounds. The non-utilization of these bio-wastes leads to economic loss and also environmental problems. Plastic is versatile and very convenient material to use as packaging material. Plastic is a non-biodegradable material which is not only hazardous to human health but also affecting environment. To overcome such problems, the study was conducted to utilize plant-based waste to develop biodegradable packaging containers. Among the various alternatives, plant-based waste like peels of orange along with wheat flour and tamarind seed kernel flour at varying levels were used to develop acceptable quality biodegradable packaging containers. The studies involved obtaining the optimized formulation by using Response Surface Methodology (RSM) for creating biodegradable containers with desired mechanical and chemical properties. The independent variables used were Orange Peel Powder (OPP), Wheat Flour (FL) and Tamarind Seed Powder (BA) as binding agent. The dependent variables were water activity and compression strength. The optimized formulation obtained from the RSM is 50.28% OPP, 35.71% FL, and 14.01% BA along with process parameters 131⁰C for 64 min. This optimized formulation produced biodegradable container with 12.63kgf compression strength and 0.21 water activity.

Production of instant cassava tuber flour for water fufu is an appealing process because of a significant reduction in cooking time, it involves less tedious preparation, the flour has improved odor with a significant increase in shelf life, and is of better quality. However, the optimum cassava fermentation and precooking parameters; two critical unit operations in the process, as well as their effects on the quality and shelf life of the product have not been studied elaborately. The Doehlert design was employed to optimize the fermentation and the precooking processes of cassava (Manihot esculenta Crantz) tuber to produce instant flour for water fufu. Second-order polynomial models with high R² (> 0.75) and low absolute error of deviation (< 5%) values between experimental and predicted results were validated for both the fermentation and pre-cooking processes and used to generate optimum cooking conditions. The optimum conditions to produce instant cassava tuber flour were 2 days of fermentation, 30 mm thick cassava slices, 200 g cassava quantity, 5 min cooking time, and 75 °C cooking temperature. Results characterizing the nutrient retention of the instant cassava flour were pH (4.98 ± 0.02), TA (0.09 ± 0.01%), carbohydrate content (20 ± 0.04%), cyanide content (0.70 mg ± 0.03%), and moisture content (8.09 ± 0.2%).

In recent years, global trends indicate consumer interest in functional foods. Thus, there is a trend to replace the use of artificial colors with natural colors that, in addition to being attractive to consumers, provide benefits to the biological functions of the human organism. The objective of this research was the solvent extraction of a natural dye from the roselle flower, its identification and evaluation of its behavior at different pH and temperatures. In addition, its application in flavored milk was evaluated sensorially. The anthocyanins located in the roselle flower were extracted by fragmentation and milling. The separation of pigments was carried out with ethanol (96%v/v) for 72 h. The qualitative tests of identification, physics and chemistry revealed the presence of anthocyanins (delphinidin 3-glucoside and cyanidin 3-glucoside). The pigments present in roselle flower are relatively stable with temperature. However, at temperatures above 80 °C a gradual degradation occurs. At different pH values, two visible absorption points are shown at 519.6 and 320.4 nm, which correspond to the two characteristic bands of anthocyanins. The milk flavored and dyed with roselle extract had a shelf life of 7 days in refrigerated storage and was sensorially accepted by consumers, but the color was unattractive.