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This article aims to analyze the effects of enzyme treatment concentration, temperature, and time on peanut protein so as to obtain an optimal enzymatic hydrolysis condition for flavorzyme (Fla) and alkaline protease (Alk). The results were as follows: enzymatic hydrolysis temperature 60 °C and 55 °C, enzyme concentration 10% and 4%, enzymatic hydrolysis time 80 min and 60 min, and double enzyme hydrolysis ratio 2% Fla + 5% Alk, respectively. The BALB/c mice were sensitized with gavage of peanut protein before and after enzyme treatment to evaluate the effects of different enzyme treatments on peanut allergenicity. Compared with the mice sensitized with raw peanuts, the weight growth rate of the mice sensitized with enzyme treatment peanut increased but not as much as the control, the degranulation degree of mast cell and basophils decreased, the inflammatory infiltration and congestion in jejunum and lung tissue decreased, the expression of proinflammatory factors and thymic stromal lymphopoietin (TSLP) gene decreased, and the secretion of specific antibodies (IgE, and IgG) decreased, and the binding ability of peanut protein with peanut-specific IgE antibodies decreased as well. The results above indicate that the allergenicity of peanut protein decreases after enzyme treatment and the dual enzyme (Fla + Alk) treatment can be much more efficient.

White salted (udon) noodles are one of the major staple foods in Asian countries, particularly in Japan. Noodle manufacturers prefer the Australian noodle wheat (ANW) varieties to produce high-quality udon noodles. However, the production of this variety has reduced significantly in recent years, thus affecting the Japanese noodle market. Noodle manufacturers often add tapioca starch to compensate for the flour scarcity; however, the noodle-eating quality and texture are significantly reduced. This study, therefore, investigated the effect of the addition of porous tapioca starch on the cooking quality and texture of udon noodles. For this, tapioca starch was initially subjected to enzyme treatment, ultrasonication, and a combination of both to produce a porous starch where a combined enzyme (0.4% alpha amylase)–ultrasound treatment (20 kHz) yielded a porous starch with increased specific surface area and better absorbent properties which are ideal for udon noodle manufacturing, Later, udon noodles were prepared using three varieties of ANW, a hard Mace variety, and commercial wheat flour by incorporating the prepared porous tapioca starch at a concentration of 5% and 10% of dry ingredients. Adding this porous starch resulted in a lower cooking time with higher water absorption and desirable lower cooking loss compared to the control sample with 5% of the porous starch chosen as the optimum formulation. Increasing the level of the porous starch reduced the hardness of the noodles whilst maintaining the desired instrumental texture. Additionally, a multivariate analysis indicated a good correlation between responses’ optimum cooking time and water absorption capacity as well as turbidity and cooking loss, and a cluster analysis grouped noodle samples prepared from different varieties into the same clusters based on the porous starch added, indicating the possibility of different market strategies to improve the quality of the udon noodles produced from different wheat varieties.

Improved methods for the extraction of eicosapentaenoic acid (EPA), an essential and economically important polyunsaturated fatty acid, are urgently required. However, lipid extraction rates using food-grade solvents such as ethanol are usually low. To improve the ethanol-based extraction rate, and to elucidate the relevant mechanisms, we used cellulase and laccase to treat powdered Nannochloropsis, one of the most promising microalgal sources of EPA. Cellulase and laccase synergistically increased lipid yields by 69.31% and lipid EPA content by 42.63%, by degrading the amorphous hemicellulose and cellulose, improving crystallinity, and promoting the release and extraction of lysodiacylglyceryltrimethylhomoserine. Scanning electron microscopy showed that cell morphology was substantially altered, with cell-wall rupture, loss of cell boundaries, and the release of intracellular substances. In conclusion, Nannochloropsis lipid yields may be directly linked to cell-wall hemicellulose structure, and enzymatic treatment to alter this may improve lipid yields.

Currently, astaxanthin demand is fulfilled by chemical synthesis using petroleum-based feedstocks. As such, alternative pathways of natural astaxanthin production attracts much research interest. This study aimed at optimising bioreactor operation parameters for astaxanthin production and evaluating strategies for its subsequent extraction. The effect of pH and agitation was evident, as a significant reduction in both biomass and astaxanthin production was observed when the culture pH was not controlled and a low agitation speed was applied. At controlled pH conditions and a high agitation speed, a significant increase in biomass (16.4 g/L) and astaxanthin production (3.6 mg/L) was obtained. Enzymatic yeast cell lysis using two commercial enzymes (Accellerase 1500 and Glucanex) was optimised using the central composite design of experiment (DoE). Accellerase 1500 led to mild cell disruption and only 9% (w/w) astaxanthin extraction. However, Glucanex treatment resulted in complete astaxanthin extractability, compared to standard extraction method (DMSO/acetone). When supercritical CO2 was employed as an extraction solvent in Accellerase-pre-treated Xanthophyllomyces dendrorhous cells, astaxanthin extraction increased 2.5-fold. Overall, the study showed that extraction conditions can be tailored towards targeted pigments present in complex mixtures, such as in microbial cells.

This article aims to analyze the effects of enzyme treatment concentration, temperature, and time on peanut protein so as to obtain an optimal enzymatic hydrolysis condition for flavorzyme (Fla) and alkaline protease (Alk). The results were as follows: enzymatic hydrolysis temperature 60 °C and 55 °C, enzyme concentration 10% and 4%, enzymatic hydrolysis time 80 min and 60 min, and double enzyme hydrolysis ratio 2% Fla + 5% Alk, respectively. The BALB/c mice were sensitized with gavage of peanut protein before and after enzyme treatment to evaluate the effects of different enzyme treatments on peanut allergenicity. Compared with the mice sensitized with raw peanuts, the weight growth rate of the mice sensitized with enzyme treatment peanut increased but not as much as the control, the degranulation degree of mast cell and basophils decreased, the inflammatory infiltration and congestion in jejunum and lung tissue decreased, the expression of proinflammatory factors and thymic stromal lymphopoietin (TSLP) gene decreased, and the secretion of specific antibodies (IgE, and IgG) decreased, and the binding ability of peanut protein with peanut-specific IgE antibodies decreased as well. The results above indicate that the allergenicity of peanut protein decreases after enzyme treatment and the dual enzyme (Fla + Alk) treatment can be much more efficient.

White salted (udon) noodles are one of the major staple foods in Asian countries, particularly in Japan. Noodle manufacturers prefer the Australian noodle wheat (ANW) varieties to produce high-quality udon noodles. However, the production of this variety has reduced significantly in recent years, thus affecting the Japanese noodle market. Noodle manufacturers often add tapioca starch to compensate for the flour scarcity; however, the noodle-eating quality and texture are significantly reduced. This study, therefore, investigated the effect of the addition of porous tapioca starch on the cooking quality and texture of udon noodles. For this, tapioca starch was initially subjected to enzyme treatment, ultrasonication, and a combination of both to produce a porous starch where a combined enzyme (0.4% alpha amylase)-ultrasound treatment (20 kHz) yielded a porous starch with increased specific surface area and better absorbent properties which are ideal for udon noodle manufacturing, Later, udon noodles were prepared using three varieties of ANW, a hard Mace variety, and commercial wheat flour by incorporating the prepared porous tapioca starch at a concentration of 5% and 10% of dry ingredients. Adding this porous starch resulted in a lower cooking time with higher water absorption and desirable lower cooking loss compared to the control sample with 5% of the porous starch chosen as the optimum formulation. Increasing the level of the porous starch reduced the hardness of the noodles whilst maintaining the desired instrumental texture. Additionally, a multivariate analysis indicated a good correlation between responses' optimum cooking time and water absorption capacity as well as turbidity and cooking loss, and a cluster analysis grouped noodle samples prepared from different varieties into the same clusters based on the porous starch added, indicating the possibility of different market strategies to improve the quality of the udon noodles produced from different wheat varieties.

Currently, astaxanthin demand is fulfilled by chemical synthesis using petroleum-based feedstocks. As such, alternative pathways of natural astaxanthin production attracts much research interest. This study aimed at optimising bioreactor operation parameters for astaxanthin production and evaluating strategies for its subsequent extraction. The effect of pH and agitation was evident, as a significant reduction in both biomass and astaxanthin production was observed when the culture pH was not controlled and a low agitation speed was applied. At controlled pH conditions and a high agitation speed, a significant increase in biomass (16.4 g/L) and astaxanthin production (3.6 mg/L) was obtained. Enzymatic yeast cell lysis using two commercial enzymes (Accellerase 1500 and Glucanex) was optimised using the central composite design of experiment (DoE). Accellerase 1500 led to mild cell disruption and only 9% ( w/w ) astaxanthin extraction. However, Glucanex treatment resulted in complete astaxanthin extractability, compared to standard extraction method (DMSO/acetone). When supercritical CO 2 was employed as an extraction solvent in Accellerase-pre-treated Xanthophyllomyces dendrorhous cells, astaxanthin extraction increased 2.5-fold. Overall, the study showed that extraction conditions can be tailored towards targeted pigments present in complex mixtures, such as in microbial cells.