Band 19, Heft 5

Lactose and sodium caseinate were used as wall materials in microencapsulation of fish oil by spray drying. Thyme, rosemary, and laurel extracts were utilized to enhance oxidative stability. Efficiency of antioxidant capacity of plant extracts was compared with BHT. Fish oil encapsulates with rosemary extract exhibited better protection against lipid oxidation (0.36 mmol MDA/kg) than the control group (2.92 mmol MDA/kg) at +4 °C. Hue angle properties of encapsulated fish oil with the laurel extract showed the highest change. The lowest peroxide value (PV) was detected in the 1500 ppm rosemary group (5.13 mEq O 2 /kg oil) and 250 ppm BHT group (5.90 mEq O 2 /kg oil) after the spray drying. Also, these groups had the lowest TBARs values during the storage. It was observed that the pAV of CG2 (BHT Control), RE1 (1000 ppm rosemary extract), RE2 (1500 ppm rosemary extract), and LE2 (1500 ppm laurel extract) groups remained below six during 8 months of storage. Volatile components of encapsulated fish oil were the highest in control, thyme and laurel extracts compared to the microcapsules with rosemary extracts in terms of total aldehyde generation. Sensory analysis showed that fresh fish odor was better preserved with rosemary extract compared to other plant extracts. It was concluded that microencapsulation of fish oil with sodium caseinate and lactose as wall material and rosemary and laurel extracts as antioxidants enhanced the oxidative stability of the microcapsules.

The random distribution model (RDM) and uniform distribution model (UDM) were used to simulate the thermal sterilization of canned fruit. The RDM was established with the radiation function, and the stability of RDM results was analyzed by simulating temperature change during thermal sterilization and determining the sterilization parameter F value of the slowest heating zone (SHZ). The performance of the distribution models in simulating thermal sterilization heating process of canned fruit with different shapes was studied using the UDM and RDM of canned yellow peach (hemispherical shell), pear (sphere), and coconut (cube). Simulation results were compared with experimental results. The flow field and temperature field distributions were used in analyzing the influence of fruits shape on the accuracy of the models. The simulation results of different RDMs were consistent with the temperature change and F value, indicating that the RDMs had stable simulation results. When the contact between two types of fruit was a point, the UDM can be used in the numerical simulation of thermal sterilization. When the contact was a non-point, the RDM was more accurate in simulating thermal sterilization. This study provides constructive suggestions for the simulation of thermal sterilization of canned fruit with different shapes.

In this work, Flammulina velutipes was used as a novel protein and fibrous structure source to prepare animal-free patties, and transglutaminase (TGase) was added to improve their functional properties. The results showed that the addition of mushroom increased the gel strength, texture profile, and sensory property of animal-free patties. However, the presence of mushroom made the microstructure of patty become loose, with large holes. Interestingly, TGase (6–8 U/g) significantly decreased the size of holes in microstructure and induced to form a uniform and compact microstructure. Because TGase decreased the content of free amino acid group and soluble protein, and induced the formation of new protein polymers with high molecular weight in SDS-PAGE results. The covalent cross-linking catalyzed by TGase helped to form a stronger gel matrix in patty, leading to the formation of patty with higher hardness, adhesiveness, chewiness, water holding capacity, and sensory scores.

In view of the problem that conventional insecticidal methods cannot inhibit the hatching of insect eggs in rice, microwave heating was used to kill the insect eggs hidden in the rice grains. The lethal conditions of microwave irradiation on insect pests in rice and the effects of microwave irradiation on the quality of rice were studied, and the process conditions that can both ensure the quality of rice and kill insects were put forward. The microwave energy density parameter was used to evaluate the lethal conditions of microwave irradiation for insect pests in rice. The results showed that the lethality ratio of insect pests was 100% when the microwave energy density was higher than 0.0325 kW h/kg. Both microwave power density and microwave power affected the quality of rice. The results concluded that the cracking ratio, chalkiness and amylose content were increased with the increase of microwave power at the same microwave power density, while the free fatty acid content was decreased. Through the study of variable microwave power process, it was found that the cracking ratio and chalkiness can be controlled below 1.5% when the heating rate of rice at the later stage of microwave irradiation was less than 0.2 °C/s. The use of two-stage variable microwave power process can eventually ensure the disinfestation and the quality of rice simultaneously.

Manual labor involved in shrimp extraction selection accounts for an extremely high proportion of processing time and also entails reduced accuracy and efficiency moreover even it could induce potential safety hazards. The key to substitute the manual process with automation lies in the identification and pinpointing of the penultimate joint in shrimps. Therefore, a cascaded neural network is proposed in this study to implement the detection of key points in a multi-shrimp scenario processing. More specifically, our model includes two stages: a shrimp detector based on YOLOv3 and followed by a pose estimator based on Convolutional Pose Machine (CPM). With the combination of attention mechanism and improved NMS strategy, our detector is equipped to resist noise interference in dense case, ubiquitous on the production line. Experimental results indicate that both the detection rate and the speed information extraction have achieved the standard of industry applications.

Red fruit oil is a potential coloring agent with high carotenoid content. Oil encapsulation could be done to improve its applicability to food products. This study evaluated the effect of different ratios of maltodextrin and whey protein during the encapsulation process of red fruit oil using spray and freeze drying. The powders were analyzed in terms of total carotenoid content, physicochemical properties, and stability. Spray drying resulted in powders with lower moisture content. Freeze drying resulted in powders with high carotenoid content in most samples. All powders showed low hygroscopicity and low crystallinity, but also low flowability. Spray-dried powders were spherical and wrinkled, while freeze-dried powders were irregular and rough. Sample with 1:1 ratio of maltodextrin and whey protein showed generally better properties in both spray and freeze drying. Freeze-dried powder showed better carotenoid stability than spray dried powder throughout the 4 weeks storage period.