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Purple sweet potato (PSP) can provide products with attractive color besides nutritious benefits in food processing. So, the compositions and color stability of an aqueous anthocyanin-based PSP extract were investigated in order to promote its wide use in food industry. PSP anthocyanins were extracted with water, and nine individual anthocyanins (48.72 ug mL -1 in total, 24.36 mg/100 g fresh PSP in yield) were found by HPLC analysis. The PSP extract also contained 17.11 mg mL of Mg. Changes in color and stability of the PSP extract, as affected by pH, heat, light and extraction process, were further evaluated. Results indicated that PSP anthocyanins had good stability at pH 2.0-6.0, while the color of PSP extract kept stable during 30 days of storage at 20 °C in dark. Both UV and fluorescent exposure weakened the color stability of PSP extract and UV showed a more drastic effect in comparison. A steaming pretreatment of fresh PSP is beneficial to the color stability.

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In this work, anthocyanin of rose residue was microencapsulated, using spray-drying (1:1 (w/w) of GA to MD, the inlet air temperature was170°C, the drying airflow rate was 5.0 m 3 /min, feed rate was 0.36 L/h) and freezedrying (processing 48 h at −52°C, vacuum degree was 0.45 mbar) with gum arabic and maltodextrin as external materials. The total phenolic content (TPC), anthocyanin content (ACN), antioxidant activity, moisture content, water activity (A w), solubility, hygroscopicity, colorimetric property, particle micromorphology and size distribution of the microencapsulated anthocyanin were measured. Thermal degradation kinetic and thermodynamic parameters of ACN extracts and microcapsules in the accelerated model were determined. The spray-dried powder (SDP) presented a spherical shape while the freeze-dried powders (FDP) were in indefinite and laminated structures with more homogeneous distribution. After microencapsulation, the retention rate of TPC and ACN was 86.00% and 75.85% for SDP, 91.44% and 95.12% for FDP, respectively. Both of spray-dried and freeze-dried strategy provided efficient preservation for rose residues, enabling them to have lower moisture content, water activity, significantly higher solubility (P < .05) compared with the rose anthocyanin extracts (RAE), and have highfidelity color that was similar to RAE. Meanwhile, the antioxidant activity of the microcapsules decreased with the deteriorating of bioactive compounds. In the degradation kinetic study of anthocyanin at the temperature 70, 80, 90°C, both FDP and SDP had longer half-life duration, lower absolute value of activation entropy, and better effect of freeze-drying embedding method compared to RAE. Therefore, microencapsulation, especially by freeze-drying method, could efficiently enhance the stability of anthocyanin in rose residue during thermal processing and storage, and thus greatly facilitate the utilization of by-product of rose essential oil.

The extraction of water‐soluble dietary fiber (SDF) from apple pomace (AP) by cellulase, microwave‐ and ultrasound‐assisted methods was studied in comparison with conventional acid method. The functional properties of extracted SDFs were further evaluated, and the speciality of each method was clarified in order to suggest the right method to adopt for practice. Results indicated that AP is rich in SDF, which is significantly potential to be applied in food processing. Acid hydrolysis of AP gave 10.3% of SDF, whereas ultrasound‐assisted extraction (UAE) provided a yield of 16.4% after 40 min of sonication. Microwave‐assisted extraction (MAE) gave a slightly lower yield (14.9%) than UAE, but it showed a drastic efficiency, wherein the yield was achieved after 2 min of irradiation. The hydrolysis of AP by cellulase occurred with the highest SDF yield (18.7%) among all the methods used. The functional properties of SDF were improved by UAE, MAE and cellulase extraction, wherein the water retention and swelling capacities were increased more considerably than the oil retention capacity. Especially, cellulase showed a remarkable performance in improving the hydration property. Practical Applications A large amount of apple pomace (AP) was produced as the by‐product of apple processing in China. Its disposal is of significance in consideration of resource utilization and environmental protection. Therefore, the results of this study can promote the full use of AP and similar industrial wastes, and also help to avoid possible pollution. In addition, the comparison of acid, cellulase, microwave‐ and ultrasound‐assisted methods suggests the right method to adopt SDF extraction method for practice.

The halal food market is globally growing along with the increased risk of adulteration. We proposed an amplification-free and mix-to-read CRISPR-Cas12-based nucleic acid analytical strategy allowing rapid identification and analysis of pork components, thus enriching the toolbox for ensuring halal food authenticity. We designed and optimized guide RNA (gRNA) targeting the pork cytochrome b (Cyt b) gene. gRNA allowed specific identification of the target Cyt b gene from pork components followed by activation of Cas12 protein to abundantly cleave single-stranded DNA probes with terminally labeled fluorophore and quencher groups, thus turning on fluorescence. The presence of the pork Cyt b gene thus can be mix-and-read- and only-one-step-detected, which may indicate the risk of halal food adulteration. The method allowed specific discrimination of pork meat from beef, mutton, and chicken and yielded a detection limit of 2.7 ng/μL of total DNA from pork meat. The reliability of the method was tested using the following processed meat products: halal foods beef luncheon meat and spiced beef and non-halal foods sausage and dried pork slices. The CRISPR-Cas12-based nucleic acid test strategy is promising for rapid food authentication.

The effect of gallic acid (GA) on the redox state of hemoglobin (Hb) and the structural mechanism upon the Hb− GA interaction were investigated. Results indicated that GA exhibited antioxidant and pro-oxidant effects on Hb, which depended on its concentration and the redox state of Hb. The antioxidant capacity of GA contributed to the inhibition of free iron release from Hb. GA could bind to the central cavity of Hb and interacted with the heme moiety through direct hydrophobic contacts as indicated by docking analysis, but GA did not disrupt the heme structure. Conversely, GA increased the compactness of the Hb molecule and might narrow the crevice around the heme pocket, which contributed to the inhibition of Hb autoxidation and the free iron release. Results provided significant insights into the interaction of GA with redox-active Hb, which is beneficial to the application of GA in relative meat and blood products.

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