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As one of the optically active components, phytoplankton are common photosynthetic organisms in oceans, nearshore, and inland water bodies. The variations in phytoplankton algal density play a crucial role in understanding primary productivity, carbon cycling, and early warning of algal blooms. In this study, three typical eutrophic lakes in China, Lake Taihu, Lake Chaohu, and Lake Dianchi, were taken as the research area. Algorithms for estimating algal density of cyanobacteria-dominated and non-cyanobacteria-dominated water types were developed based on Mie theory. The results demonstrated that the developed algorithm had favorable estimation performance for inland eutrophic lakes, with a determination coefficient (R2) of 0.88, a mean absolute percentage error (MAPE) of 51%, an unbiased mean absolute percentage error (UMAPE) of 39%, and a root mean square error (RMSE) of 23.99 × 106 cells/L. Furthermore, comparison with other algorithms for estimating algal density showed that the developed algorithm had the lowest MAPE of 60% and UMAPE of 43%, with the RMSE of 23.42 × 106cells/L. Extensive evaluation based on satellite-ground synchronous data demonstrated the applicability of the developed algorithm to the Sentinel-3 OLCI sensor, enabling the determination of spatial and temporal distribution characteristics of algal density in the three lakes from 2016 to 2022 using Sentinel-3 OLCI images. The results of algal density inversion revealed a continuous decreasing trend in algal density in Lake Dianchi from 2016 to 2022, while the algal density in Lake Taihu and Lake Chaohu both decreased after 2019.

Compared with the rice-acid soup inoculated with single starter, the synergistically intensified rice-acid soup inoculated with Lactobacillus paracasei H4-11 (L. paracasei H4-11) and Kluyveromyces marxianus L1-1 (K. marxianus L1-1) contained more flavor compounds. Organic acids mainly included L-lactic acid and the main volatile flavor component was ethyl acetate. Moreover, the signal intensity of astringency and bitterness and the total concentration of volatile sulfur compounds were reduced. The combined analysis results of RNA sequencing (RNA-seq) technology and 4D label-free quantitative (4D LFQ) proteomics explained the flavor formation pathways in rice-acid soup inoculated with L. paracasei H4-11 and K. marxianus L1-1. In L. paracasei H4-11, L-lactate dehydrogenase, phosphoglucomutase, acetate kinase, alcohol dehydrogenase and acetyl-CoA were up-regulated and D-lactate dehydrogenase and N-Acetyltransferase were down-regulated. In K. marxianus L1-1, Acetyl-CoA, acetaldehyde dehydrogenase, acyl-coenzyme A, N-acetyltransferase, and L-lactate dehydrogenase were up-regulated and hexokinase, alcohol dehydrogenase, and alcohol O-acetyltransferase were down-regulated. The above up-regulation and down-regulation synergistically promoted the formation of characteristic flavor compounds (mainly L-lactic acid and ethyl acetate). Enzyme-linked immunoassay (ELISA) and parallel reaction monitoring (PRM) quantitative analysis respectively verified that 5 key metabolic enzymes and 27 proteins in L. paracasei H4-11 and K. marxianus L1-1 were associated with the characteristic flavor of rice-acid soup, as confirmed by the quantitative results of 4D LFQ.

In the present study, a new degraded konjac glucomannan (DKGM) was prepared using a crude enzyme from abalone (Haliotis discus hannai) viscera, and its physicochemical properties were investigated. After enzymatic hydrolysis, the viscosity of KGM obviously decreased from 15,500 mPa·s to 398 mPa·s. The rheological properties analysis of KGM and DKGMs revealed that they were pseudoplastic fluids, and pseudoplasticity, viscoelasticity, melting temperature, and gelling temperature significantly decreased after enzymatic hydrolysis, especially for KGM-180 and KGM-240. In addition, the molecular weight of KGM decreased from 1.80 × 106 Da, to 0.45 × 106 Da and the polydispersity index increased from 1.17 to 1.83 after 240 min of degradation time. Compared with natural KGM, the smaller particle size distribution of DKGM further suggests enzyme hydrolysis reduces the aggregation of molecular chains with low molecular weight. FT-IR and FESEM analyses showed that the fragmented KMG chain did not affect the structural characteristics of molecular monomers; however, the dense three-dimensional network microstructure formed by intermolecular interaction changed to fragment microstructure after enzyme hydrolysis. These results revealed that the viscosity and rheological properties of KGM could be controlled and effectively changed using crude enzymes from abalone viscera. This work provides theoretical guidance for the promising application of DKGM in the food industry.

The physicochemical properties and composition of coix seed oil produced by Monascus purpureus fermentation and supercritical CO2 extraction were determined. Anti-lipid-oxidation and edible safety were evaluated using a cholesterol-fish oil model, acute oral toxicity assay, and genetic toxicity assay in vitro and in vivo, respectively. The results show that the extraction oil from fermented coix seed (FCS-O) had good physicochemical quality and abundant active components with physiological function. In particular, γ-tocotrienol, γ-oryzanol, coixenolide and oleic acid concentrations reached 72.83 µg/g, 745.96 µg/g, 9.65mg/g and 316.58 mg/100 g DW, respectively. The FCS-O exhibited higher antioxidant capability in inhibiting lipid oxidation and peroxidation. Compared to the blank control, the concentrations of 7-ketocholestreol and peroxide only were 8.42 µg/mL and 16.16 mmol/kg at 168 h of oxidation (P < 0.01). In addition, the FCS-O has been confirmed to be a very safe edible oil, with no acute toxicity (LD50 > 10 g/kg bw, considered actually non-toxic) and no induced mutagenicity, cytotoxicity or genotoxicity. These results serve as a good safety reference for future application of the oil from fermented coix seed. The development and utilization of this kind of oil will be beneficial as a food, food ingredient, nutritional supplement, or natural food antioxidant to promote good health function.

Milk fat globules or milk fat globule membranes (MFGs/MFGM) have been added to the infant formula to fortify the phospholipids and narrow the nutritional gap from breast milk. The main aim of this study was to profile the interfacial and thermal properties of MFGs/MFGM prepared from ultrasonicated bovine milk. Bovine milk was sonicated at ultrasonic intensities of 20 kHz and 40 kHz independently or synchronously with the duration time of 0 min (control), 5 min, 10 min, and 15 min (work/rest cycles = 5 s: 3 s). Ultrasonic treatments at 20 kHz/ 5 min and 20 + 40 kHz/ 5 min improved the volume density (%) of smaller particles (1–10 µm) while significantly decreasing the surface hydrophobicity (H0) (p 0.05). X-ray diffraction (XRD) results showed that α-crystal peaks only existed in control and ultrasonicated 5 min samples but disappeared in all 15 min samples. According to the different scanning calorimetry (DSC), one or two new exothermic events (in the range of 17.29 – 18.81 ℃ and 22.14 – 25.21 ℃) appeared after ultrasonic treatments, which, however, were not found in control samples. Ultrasonic treatments resulted in the low-melting fractions (LMF) (TM1) peaks undetectable in MFGs/MFGM samples in which only peaks of medium-melting fractions (MMF) (TM2) and high-melting fractions (HMF) (TM3) were detected. Compared with the control, both enthalpies of crystallisation (ΔHC) and melting (ΔHM) decreased in ultrasonicated samples. In conclusion, ultrasonic treatment affects the interfacial and thermal properties of MFGs/MFGM.

Powder breakage during pneumatic conveying negatively affects the properties of dairy products and causes increased dusting, reduced wettability, and decreased product performance. In particular, particle breakage is a serious issue for fat-filled milk powder (FFMP) which, if it breaks, releases fat that causes odours and leads to sticky blocked pipes. In this work, a conveying rig (dilute phase, positive pressure) with 50 mm diameter food grade stainless steel pipes (1.5 m high and 5 m conveying distance with three 90° bends, two in the vertical plane and one in the horizontal plane) was built as the test system. The effects of operating conditions (conveying air velocity and solid loading rate) on the attrition of FFMP in a dilute phase conveying system were experimentally studied. Four quality characteristics were measured before and after conveying: bulk density, particle size distribution, wettability, and solubility, to access the influence of particle breakage. Conveying air speed shows a significant impact on powder breakage. As air speed increased, more breakage occurred, and the volume mean diameter D[4,3] decreased by around 50%, using the largest conveying air speed of 38 m/s. Bulk density increased accordingly whereas wettability decreased with an increase in air speed, resulting from the higher breakage rate. On other hand, improving the solid loading rate can further reduce the breakage level, but the positive effect is not as good as decreasing air speed.