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Freshly harvested Jerusalem artichoke tubers contain inulinase, which needs to be inactivated. Otherwise, inulin from Jerusalem artichokes is easily hydrolyzed by inulinase into fructose, which can be lost or consumed by bacteria during the marination process. The traditional pickling process lasts for six months, and a large amount of salt (18%–20%) is added during the pickling process. This production process is uneconomical and increases nitrite intake, and the miscellaneous bacteria that are produced during the pickling process affect product taste. In this study, reasonable enzyme inactivation methods, including NaCl, NaHCO3, and ultrasound, were evaluated. NaHCO3 showed the strongest enzyme inactivation; however, the quality and flavor of the obtained Jerusalem artichoke pickles were not ideal. The sensory flavor of Jerusalem artichoke pickles inactivated by NaCl was better, and enzyme inactivation was not obvious after ultrasound treatment, but ultrasound combined with NaCl resulted in enzyme inactivation. The inulinase activity of Jerusalem artichokes was reduced to 2.50 U/mL, and the inulin content was maintained at 61.22%, when the ultrasonic and NaCl combination treatment was applied. The strain LS3, identified as Enterococcus faecalis, and YS5, identified as salt-tolerant yeast Meyerozyma guilliermondii, were the dominant microorganisms isolated from the pickle juice. Jerusalem artichokes with inactivated inulinase were pickled with microbial powder, separated, purified, and dried to remove the natural Jerusalem artichoke sauce. This workflow shortened the fermentation cycle and improved product quality.

Three-dimensional printing (3D printing) technology based on slurry extrusion makes it possible to realize rapid manufacture of personalized, refined and complex ceramic products. The ceramic slurry for extrusion molding which is affected by various factors requires excellent extrusion properties and shape retention capacity. In this paper, the methods of orthogonal experiment design (OED) and back propagation artificial neural networks (BP ANNs) were combined to solve multi-objective and multi-factor problems caused by the preparation of alumina slurry. Through the combined model, the relationship between extrusion parameters and influencing factors of the slurry was obtained. The predicted optimal values were consistent with the experimental results, which proves the validity of the model. Alumina slurry suitable for 3D printing with excellent extrusion and shape retention properties was successfully prepared. The method is also applicable to the study of other multi-objective and multi-factor ceramic materials.

Barley grass possesses high nutritional value and antioxidant properties. In this study, the phytochemical constituents and antioxidant enzyme activities in six cultivars of barley grass were explored at three developmental stages: tillering, jointing, and booting stages. Total chlorophyll (Chl t) and carotenoid (Car) content, chlorophyll a/b (Chl a/b) ratio, total nitrogen nutrition (TNN), and total soluble protein (TSP) content, and superoxide dismutase (SOD), peroxidase (POD), and polyphenol oxidase (PPO) activities were assayed. The results indicated that the cultivar &times, development interaction was significant and that developmental stage was the main factor affecting the parameters studied. Cultivars had a negligible effect on these parameters, which varied with the developmental stages. In the tillering stage, Chl t and Car content, TNN, and POD activity achieved their highest value, in the jointing stage, SOD activity peaked, in the booting stage, Chl a/b ratio, TSP content, and PPO activity showed their highest values. TNN showed a negative correlation with TSP. Compared with those in the jointing, Chl t, Car, TSP, TNN content, Chl a/b ratio, and POD and PPO activities increased in the booting and the tillering stages, whereas SOD activity decreased. The differences in phytochemical constituents and antioxidant enzyme activities in barley grass were mainly correlated with the developmental stages. The aim of this study was to demonstrate the influence of developmental stages of barley grass on its phytochemical profile and antioxidant activities. Our results will help understand the mechanism of action of barley grass and provide theoretical support for the therapeutic application of barley grass.