Journal of Food Measurement and Characterization最新文献

This study reports the fabrication of a novel voltammetric platform based on the modification of screen printed gold electrode (SPGE) with palladium and copper (Pd-Cu) bimetallic microparticles. The novel platform (Pd-Cu/SPGE) was applied for the voltammetric determination of amaranth in fruit soda, orange juice, and tap water. The modified electrode was characterized using scanning electron microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry. The electrode surface area of the Pd-Cu/SPGE is about two times larger than that of the SPGE. Differential pulse voltammetry was used to determine the amaranth. The chromatographic method was preferred for the reference method. At the optimal parameters, the anodic peak current of amaranth was found to be linearly dependent on its concentrations ranging from 0.002 to 15.00 µM. The detection limit was 0.5 nM (S/N = 3). For the analysis of amaranth, 101.16–104.33% of recovery percentage was obtained. This highly selective and sensitive electrode supplied the fast determination of amaranth in real samples. At a 95% confidence level, the values obtained from voltammetric and chromatographic analyses are in agreement.

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This experiment was designed to investigate the impact of different extraction techniques on the yield, and physicochemical, functional, and morphological properties of okra varieties. Specifically, combined ultrasound-microwave extraction UMAE exhibited a significantly higher extraction yield (23.99%) compared to microwave-assisted extraction MAE (15.29%), ultrasound-assisted extraction UAE (14.01%), and hot water extraction HWE (11.72%). Functional attributes such as water-holding capacity, solubility, and swelling index were significantly affected by these four extraction methods. The utilization of UMAE extraction led to a decrease in extraction time and displayed a significantly higher level of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging antioxidant activity (89%) and ferric-reducing antioxidant power (687 μmol TE/100 g), in comparison to other extraction techniques. All crude okra polysaccharides showed similar structural features via FTIR but exhibited diverse morphological features. The combined UMAE extraction method has the potential to effectively overcome the limitations of the three existing extraction procedures and enhance the extraction yield in an eco-friendly environment. The results showed that the Sabaz Pari variety and the UMAE extraction yielded the most favorable outcomes. Additionally, UMAE may serve as a potential source of food hydrocolloids with novel functional and biological properties adaptable to the food industry.

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Pulsed light (PL) treatment is considered an emerging method for processing liquid foods. Efficient liquid food treatment design requires determining fluence to estimate microorganisms’ inactivation kinetics and develop effective treatment protocols. Despite available tools to determine PL equipment fluence, these are often costly and overlook the inherent photothermal mechanism. This research aims to analyze doses irradiated by PL equipment at 5.74 cm and 10.82 cm from the luminesce source, estimating the dose distribution across a simplified petri-dish-based sample holder, and validating results through Escherichia coli ATCC 25922 inactivation in guava nectar and pineapple juice. Results showed that correcting emitted doses for distance and absorbance yielded suitable adjustments, but including the temperature and color change factors strongest aligned the theoretical estimations with actual doses. This underscores a more pronounced correlation between the calculated dose and the inactivation of E. coli in guava nectar and pineapple juice.

In this study, the effects of roasting at different times in hot air and microwave oven on the bioactive properties, fatty acid compositions, mineral contents and phenolic components of pine nut kernels and oils were investigated. According to the results obtained, the moisture quantity of pine nuts generally decreased due to roasting. The lowest moisture content belongs to the sample roasted for 17 min in a microwave oven with 2.66%. Roasting processes on oil content gave positive results, and the sample that provides the highest content (48.4%) is the sample that was roasted for 7 min in hot air. Roasting processes increased the protein content in general, and the samples with the highest protein content were roasted in a microwave oven for 17 min (26.16%). When the ash content is examined, it has been determined that the oven and microwave oven roasting processes reduce the amount of ash. While the total phenol content of the kernels increased inversely with the roasting times, the total phenol content of the oils increased unevenly depending on the roasting times compared to the control sample. Gallic acid is the most frequently detected phenolic component in pine nut kernels and oils. The highest flavonoid content in the kernels was measured with 9 min roasting (12.81 mgqE /100 g) in the microwave oven, while roasting for 7 min in the oven gave the lowest value (7.86 mgqE /100 g). On the other hand, the highest value in oils with 20.6 mgqE /100 g belongs to the samples roasted in an oven for 7 min. In general, the antioxidant activity value of pine nut kernels roasted in an oven and microwave oven showed a partial increase compared to the control. The antioxidant activity values of the oils gave similar results and it was seen that the results were not affected by the roasting times. The most frequently detected minerals in pine nut samples were N, P, K, Mg, S, Ca, Fe, Zn, Mn, Cu and B, in decreasing order. The most abundant fatty acids in pine nut oils were linoleic and oleic acids, and roasting had a slight negative effect on the fatty acid composition.

This study explored the ultrasonic-microwave synergistic extraction technique for obtaining cinnamaldehyde and cinnamic acid from cinnamon twigs, and determined the most favorable extraction conditions. The optimization of extraction parameters, including extraction time, ethanol concentration, liquid-to-solid ratio, and microwave power, was achieved through single-factor experiments and the response surface method. The results of the significance analysis indicated that ethanol concentration and extraction power were the two primary factors affecting the extraction rates of cinnamaldehyde and cinnamic acid. Under the optimal conditions—600 W microwave power, 75% ethanol concentration, a liquid-to-solid ratio of 1:15, and a 20-min extraction time——the extraction efficiency of cinnamaldehyde and cinnamic acid was significantly improved compared to traditional methods. Moreover, the use of the ultrasonic-microwave synergistic extraction technique demonstrated higher efficiency and lower environmental impact due to reduced waste production. The study also revealed that cinnamaldehyde and cinnamic acid in cinnamon twigs exhibited strong polarity characteristics and microwave absorption capacity, contributing to enhanced cell disruption and increased natural product release. These findings provide a robust basis for the development of an efficient and environmentally friendly extraction process for these valuable bioactive compounds.

The mint coriander sauce (MCS) prepared using fresh herbs is known to be heat-sensitive and highly perishable with a limited shelf life (less than 2 days). Therefore, in the current study, the aim was to develop a shelf-stable MCS utilizing gamma radiation without the use of thermal processing. The D₁₀ values for yeast and mold (Y&M) and total viable counts (TVC) were observed to be 1.18 and 6.70 kGy, respectively. The gamma radiation at a dose of 25 kGy successfully achieved microbial sterility in MCS. No microbial growth was observed in irradiated samples during the entire storage period of 180 days. Significant (P < 0.05) increase in content of phenolic acids was observed during storage. After storage of 180 days, the amount of caffeic acid, vanillic acid and ferulic acid increased by 1.35, 5.71 and 2.14 fold, respectively. In comparison with fresh samples, the irradiated samples after storage showed a significant (P < 0.05) increase of 0.6 and 0.9 fold in total antioxidant activity and total phenolic content, respectively. Although, irradiation did not show significant effect on volatile aroma constituents, however, during storage a significant (P < 0.05) loss in aroma compounds was noted. During color analysis, a marginal loss in greenness and an increase in browning index (BI) were observed. MCS samples subjected to radiation treatment maintained acceptable sensory quality during the entire storage period of 180 days. These results suggested that radiation treatment can be a practical proposition for preparing a shelf-stable MCS with excellent sensory quality.

Sericin has garnered substantial interest in biomedicine, cosmetics, and functional food. Fibroin-deficient mutant cocoons yield sericin of higher-quality with more promising application prospects compared to their wild-type counterparts. However, current studies on sericin’s bioactivities are primarily focus on wild-type sources, posing a challenge in obtaining high-quality sericin. To delve deeper into the potential of sericin from mutant silkworms, three varieties of fibroin-deficient mutant silkworm cocoons were selected. Employing high-temperature and high-pressure (HTHP) methodologies facilitated the extraction of sericin from these cocoons. After hydrolyzing the three types of sericin with trypsin, their hydrolysates showed impressive antioxidant capacity. At the concentration of 3.2 mg/mL for each type of hydrolysate, more than 65% of DPPH free radicals and 90% of ABTS free radicals were cleaned. Moreover, they can inhibit at least 40% of tyrosinase and exert a remarkable inhibitory impact on tyrosinase activity. Importantly, the sericin hydrolysates can significantly protect cell against oxidative damage. Additionally, these three types of sericin have significant effects in inhibiting melanin production. The observed variations in bioactivities across these diverse sericin varieties are particularly fascinating.

In this study, to optimize the production conditions for obtaining maximum phycocyanin (PC) from Arthrospira platensis-M2, carbon (crude/technical glycerol) sources were examined in mixotrophic cultivation. The best production of PC was determined on the 15th day in mixotrophic cultivation (1 mM crude glycerol) as 3.75 ± 0.12 mg/g. The levels of bioactive components like total-protein, -carbohydrate, -lipid, and -carotenoid, chlorophyll-a, b, total-phenolic, -flavonoid and -tannin, lipid peroxidation, pyruvate, and proline were also investigated under optimal conditions. Then wet, lyophilized, oven-dried, and frozen samples were mixed with ultrapure water/buffer at four-different concentrations and mixer mill, freeze–thaw, homogenization, and ultrasound-assisted extraction (UAE) were applied to optimize PC extraction. PC extraction conditions were determined as 30 min at 80 kHz in the simple and environmentally/friendly UAE of a 5% ultrapure water-sample. Subsequently, ammonium sulphate (AS), organic solvent, and polyethylene glycol precipitation methods were applied. The best result was determined as AS precipitation at 50% saturation. After the sample was applied to DEAE-Sepharose column chromatography, the best fractions collected were combined and passed through the ultrafiltrate. Thus, PC with 2.30-reagent purity was obtained. Then, antioxidant (DPPH·, HO·, NO·, ABTS^·+, O₂^·−, metal chelating, total reducing power, and FRAP) and cytotoxic (OE-33 and HeLa cancer cells) properties of PC were detected. Additionally, UV–Vis spectrum, FT-IR, and TGA characterizations of PC were performed. To the results, it appears that partially purified PC, with its economical production in the presence of crude glycerol, can be considered a value-added bioactive product with potential for use in various industrial fields.

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Standardization is paramount for the production and quality control of medicinal plants and their derivatives. One method of achieving standardization is through chemical fingerprinting. Among various techniques, colorimetric sensor arrays are deemed a reliable method for the quality control and diagnosis of medicinal plants. Unlike conventional methods such as DNA barcoding and spectroscopy, chemical fingerprinting offers a different analysis of the plant’s unique chemical patterns. Colorimetric sensor arrays were chosen for their cost-effectiveness, ease of use, and rapid results. The objective of this study was to devise an effective method for the classification of ten different commercial brands of thyme and to compare them with three reference original thymes using a colorimetric sensor array technique coupled with mathematical data analysis methods. The findings indicated that colorimetric sensor arrays could effectively represent noticeable color changes between different essential oil samples based on Color Difference Maps (CDMs). The subsequent application of multivariate pattern recognition methods improved the discrimination ability between the samples. Principal Component Analysis (PCA) revealed the discrimination of three classes of the samples with 93% of the total variance, highlighting the distinct separation between different thyme origins. Hierarchical Cluster Analysis (HCA) elucidated the similarity of the studied commercial samples to the reference samples of thyme essential oil, demonstrating clear grouping patterns. Furthermore, Partial Least Squares Discriminant Analysis (PLS-DA) indicated that the majority of commercial samples were as similar as the thymus vulgaris samples, with fitting and validation accuracy of 95% and 91%, respectively. This analysis effectively discriminated the commercial thyme essential oil samples, highlighting their notable similarities to specific reference samples and clarifying the alignment or deviation from different reference standards. Lastly, Linear Discriminant Analysis (LDA) confirmed previous results and differentiated the Thymus samples from zataria multiflora, with 100% fitting and 91% cross-validation accuracy. These methods together provided a comprehensive analysis, each contributing unique insights into the classification and potential standardization of thyme quality detection. Among the used sensing elements, 4 top sensor elements were identified using the factor loadings for the first three PCs of PCA analysis and discrimination ability. While this study primarily focuses on classification, it lays a strong foundation for future standardization efforts in quality control of thyme.

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The aims of the present experiment were to encapsulate Persian lime peel extract (LPE) into the tragacanth gum (TG) nanofibers using an electrospinning technique and investigate their utilization as antioxidant packaging in controlling the lipid oxidation of fresh butterfat during prolonged shelf-life storage. The tensile strength, Young’s modulus, elongation at breaks, and water vapor permeability of TG nanofibrous mats were in the range of 3.77–4.54 MPa, 39.53–68.64 MPa, 7.75-10.33%, and 6.25–14.12 × 10^‾5 g mm/m² h Pa, respectively. The lag phases of the peroxide value, p-anisidine value, and acid value for both treated butterfat samples with TG + LPE 1% and TG + LPE 3% nanofiber mats were determined to be 20 days, suggesting that the developed nanofiber mats can be successfully applied as antioxidant packaging materials for retarding the oxidation changes of fresh butterfat in the food industries.