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Summary: In this study, the ultrafine grinding (UG) and high pressure homogenization (HPH) treated slurry on the particle size and rheological property of slurry, texture, in vitro starch digestibility, and multiscale structure of steamed rice bread (SRB) were investigated. Then, it was found that the average particle size of slurry treated by UG and HPH reduced from 84.6 to 38.6 μm and 22.6 μm, respectively. The rheological properties results demonstrated that G′ resulted in higher values than G″, and that the values of G′, G″ and tan δ of slurry decreased obviously after UG and HPH treatment. Obviously, the hardness and viscidity of SRB made by UG and HPH were lower, while the elasticity and specific volume were higher. The determination of in vitro starch digestibility revealed that UG treated on slurry accelerated the starch hydrolysis rate of SRB, resulting in an increase in the pGI from 76.17 to 79.36, while HPH treatment reduced the pGI from 76.17 to 73.49. Furthermore, XRD and FTIR demonstrated that both UG and HPH increased the intermolecular hydrogen bonds, and both treatments also assisted in starch arrangement for increasing the ordered crystallization of starch, which may contribute to the increasing amylose content. [ABSTRACT FROM AUTHOR]

To explore the effect of commercial Saccharomyces cerevisiae on the quality of traditional "Wanergao" for reasonable consuming guidance, the dominant microbes, physicochemical property, free amino acid content, texture, and sensory properties during fermentation of "Wanergao" were illustrated in this paper. Compared with the samples in the control group, "Wanergao" samples in the two groups that were subjected to S. cerevisiae inoculation had weaker acidity (the pH values dropped from 4.39 ± 0.08 to 4.36 ± 0.07 and 4.36 ± 0.07 within 2 h during fermentation), higher fermenting rate (volume increased from 100 ± 1.31 to 305 ± 4.61 and 316 ± 4.93 mL separately within 3 h), and the dominant lactic acid bacteria and yeast being leukonid and S. cerevisiae. More amylose, ethanol, and free amino acid were detected in "Wanergao" produced with S. cerevisiae inoculation compared with "Wanergao" produced by sourdough. The two kinds of "Wanergao" presented various hardness (2318 ± 112, 2279 ± 103), springiness (0.76 ± 0.03, 0.71 ± 0.03), chewiness (1.43 ± 0.05, 1.41 ± 0.06), and cohesiveness (0.68 ± 0.03, 0.62 ± 0.03) after fermentation. The result of sensory analysis revealed that "Wanergao" in the S. cerevisiae group had higher elasticity, aroma, and restoring force. The experiment demonstrated that "Wanergao" produced by using S. cerevisiae is a kind of fermented rice product with rich fragrance, high amount of nutrients, and strong elasticity. [ABSTRACT FROM AUTHOR]

We previously screened a whole-cell lipase EC 3.1.1.3 from the novel strain Aspergillus niger GZUF36, which exhibited 1,3-selectivity in the synthesis of 1,3-diacylglycerol via glycerolysis. However, the mechanism of lipase selectively in catalyzing the sn-1,3 position remains ambiguous. This work was performed to investigate the 1,3-selective mechanism of lipase using glycerolysis to synthesize 1,3-diacylglycerol (1,3-DG) as a model reaction by changing solvent(s) and water activity (a), and addition of salt hydrate pair. The measured diacylglycerol yield was also used to examine lipase activity. Results indicated that not only organic solvent and a have strong effect on the sn-1,3 selectivity, but also ions of salt hydrate pair also affected selectivity. Lipase conformation was altered by hydrophobic interactions of the solvent, a, or ions of salt hydrate, resulting in distinct sn-1,3 selectivity of the lipase. The salt hydrate pair changed the lipase conformation and selectivity not only by a but also by static interactions, which was rarely reported. These parameters also affected lipase activity. The lipase displayed the highest selectivity (about 88%) and activity in solvents of t-butanol and n-hexane (1:29, v/ v) at a 0.43. The results demonstrated that the sn-1,3 selectivity and activity of the lipase from A. niger GZUF36 may be improved by control of some crucial factors. This work laid a foundation for the application of lipase in the synthesis of 1,3-DG and other structural and functional lipids. [ABSTRACT FROM AUTHOR]

The term maturity value (M) can be physically defined as the equivalent heating time (min) that is required for when culinary quality reaches a degree of being cooked properly at a specific reference temperature. The M value is a dynamic function which describes the change of the food quality being fully cooked and characterizes the degree of being fully cooked in cuisine. The termination maturity value (MT) is the M value reached at the time of being fully cooked. "Huohou" can be dynamically defined as the culinary operation minimizing the over-heated value when culinary quality reaches being fully cooked. Theoretic analysis and numerical simulation were studied in previous literature; however, whether the MT value exists or not, or whether its value is steady and merely relates to dynamic parameters and thermal history, has not been verified by experiments until now. As a result, it was necessary to measure MT value and its z value and analyze the influence factors under designed experimental conditions. A method to measure the MT value was established for the selected samples—pork loin. As the judgment of being fully cooked is subjective, sensory evaluation was used in cuisine. Firstly, samples with specific M values determined by the system of data acquisition and analysis on heat transfer and kinetics were prepared under different experimental conditions, i.e. size, shape, initial temperature, temperature and type of heating medium. In addition, a selection method of sensory evaluation difference tests was used to confirm the degree of being fully cooked in samples according to color, odor and texture, respectively. Under these conditions, the corresponding MT of color, odor and texture were regarded as the average M of being fully cooked samples. Based on the color, odor and texture weight given by experts, an integrated MT was acquired by the weighted average. Finally, a set of MT was obtained in the light of a different z value under the same experimental conditions. A corresponding z was the reasonable zM of cuisine being fully cooked when this set of MT standard deviation was minimum. The results indicated that an average IMT of A and B of pork loin were 0.51 and 0.31 min respectively, and MT values were proven to be invariable under different sizes, shapes, initial temperatures, temperatures and type of heating mediums, and could only be determined only by different pork loins. Since the zM value of M represents the sensitive degree of being fully cooked to heating; the lower the zM value, the easier being fully cooked is to be reached. The zM of meat cuisine M value was close to 10℃, which was inferred, approximately, from experimental results and the z value range of protein denaturation. For the same sourced pork lion, center points had different thermal histories and being fully cooked time had the same cooked quality when samples reached the same center MT. The above experimental result has provided evidence for the M value theory. M value is merely related to thermal history and zM; therefore, it can be widely used in cuisines especially suitable for the engineered calculated process of food being fully cooked. The above-mentioned results conformed to the definition of the MT value and the relevant parameters scope. To prove the M value theory thoroughly, much more in-depth and widespread experiments will be required. [ABSTRACT FROM AUTHOR]

The development of rapid and sensitive detection technologies for animal epidemic diseases is very important to early diagnosis and disease control. Biosensing technology is a novel biological detection technology developed in recent years and has been listed as one of the five medical inspection technologies in the 21st century, which is considered as a rapid and effective technology for detection and diagnosis of animal epidemic diseases. In this paper, the latest research progresses on the application of biosensing technology in detection of bacterial infectious diseases, viral infectious diseases and parasitic diseases were summarized. [ABSTRACT FROM AUTHOR]

GDSL-type esterases are promising biocatalysts for the food and pharmaceutical industries. Here, a GDSL-type esterase from Aspergillus niger CCTCC No. M2012538 (INANE1) was expressed and purified in Pichia pastoris GS115, and its catalytic performances were evaluated, including the synthesis of cinnamyl acetate and deacetyl-7-aminocephalosporanic acid (D-7-ACA). In addition, molecular docking and molecular dynamics simulations analyzed INANE1's substrate specificity. The substrate specificity profile indicated the recombinant esterase (rINANE1) was an acetylesterase with high specificity for p-nitrophenyl acetate (p-NPA). The rINANE1 exhibited maximum activity at pH 8.0 and 35 °C, where K m and V max were calculated as 0.13±0.03 mM and 22.56 ± 0.32 μmoL/min/mg, respectively. The yield of cinnamyl acetate of about 85 % was achieved in 24 h. The conversion rate of 7-aminocephalosporanic acid (7-ACA) could reach 92.71 ± 1.78 % at 25 °C and 2.5 h. Moreover, the INANE1 structure model, molecular docking, and molecular dynamics simulation demonstrated that the pocket of the catalytic triad Ser34, Asn267, and His270 could only accommodate p-NPA. INANE1 may be the first fungi esterase with cinnamyl acetate synthetic activity and 7-ACA hydrolysis activity. Therefore, INANE1 would be a promising enzyme with industrial values., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interests., (Copyright © 2024. Published by Elsevier Inc.)

Chinese cooking is the primary treatment method for table food in China. The process is complex and large-scale, which is important to the macroeconomy and national nutrition and health. First, this article puts forward the concept of thermal accumulation for Chinese cooking by taking pork tenderloin fried at different oil temperatures, explaining changes in moisture content, hardness, and color with different thermal accumulation conditions, and measuring kinetic parameters. The variations of L * and b * obtained by the experimental results belong to the first-order reaction kinetic model, while the changes in water content and shear force belong to the zero-order reaction kinetic model. Simultaneously, the superheat value is used as a thermal accumulation indicator, combined with sensory evaluation to determine that the Z value of the human sensory overheating of pork tenderloin is 99°C, and O s ,max ( Z  = 99°C, the reference temperature is 110°C) is 5.86 min., Competing Interests: The authors declare no conflicts of interest regarding this article., (© 2023 The Authors. Food Science & Nutrition published by Wiley Periodicals LLC.)

The study aims to determine the optimum sterilization rate and water activity of Chinese traditional smoke-cured bacon product (Larou) in the preservation with natural coating solution. With the response surface methodology (RSM), we analyzed 3 factors of processing conditions (the concentration of lysozyme, concentration of sodium alginate, and concentration of chitosan) and 2 response factors (sterilization rate and water activity). Sterilization rate and water activity of Larou were largely affected by the concentration of lysozyme, concentration of sodium alginate, and concentration of chitosan. The final optimum concentrations of lysozyme, sodium alginate, and chitosan were 0.09, 1.40, and 1.60% and realized the high sterilization rate. Water activity of sliced Larou was significantly correlated with the sterilization rate. Low-field nuclear magnetic resonance analysis verified the optimum processing conditions. The coating resulted in 99.69% rate of reducing bacteria after 30-day storage. The data of the total number of colony, peroxidation value, moisture content, pH, and sensory evaluation provided the theoretical basis for extending the shelf life of Chinese traditional smoke-cured bacon product (Larou) with natural coating solution.