Bioengineered xylanase from Misiones Argentina rainforest: A bakery enhancement approach.

In this study, we pursued the heterologous expression of the xylanase gene from Trichoderma atroviride, a native fungus in the province of Misiones, and used it to enhance the textural properties of baked goods through varying enzymatic concentrations. This marks the inaugural exploration into its functionality in the context of bread production. The recombinant xylanase exhibited improved activity, reaching 36,292 U L-1, achieved by supplementing the culture medium with dextrose. Following the optimization of recombinant xylanase concentration, promising results emerged, notably reducing hardness and chewiness parameters of bread significantly. Our findings underscore the potential of this native fungal enzyme for industrial processes, offering a sustainable and efficient means to enhance the quality of baked goods with broad implications for the food industry. No prior research has been documented on the heterologous expression of the xylanase gene derived from T. atroviride, from the Misiones rainforest, expressed in Kluyveromyces lactis. PRACTICAL APPLICATION: This research, focusing on the isolation and cloning of xylanase enzyme from Trichoderma atroviride, a native fungus in the province of Misiones, offers a valuable tool for improving the texture of bakery products. By optimizing enzyme concentrations, our findings present a practical approach for the food industry, offering a viable solution to improve the overall quality and consumer satisfaction of bakery products.

Effect of the incorporation of pregelatinized cassava starch on the physicochemical, textural, and acoustic characteristics of baked snacks.

Almost all the dehydrated cassava puree is pregelatinized cassava starch (PCS). Its potential application in food would add variety. But food characteristics vary depending on the raw materials used. We examined how the structure of snacks changed when PCS was used instead of flour in terms of porosity, instrumental textural parameters, and acoustic parameters and compare them to commercial crackers. The volume of air was unaffected by the substitution. However, substitution did reduce thickness and alter the number, size, and wall firmness of pores, as well as their distribution and shape, which raise the values of firmness, fracturability, hardness, and fragility, though not linearly. The partial substitutions and the control did not exhibit any appreciable differences in the acoustic parameters. The total replacement sample was noisier and maintained a wide variety of sounds. The PCS vitreous state is primarily responsible for structure changes, but other elements, such as processing conditions, contribute to differences in comparison to the commercial samples. The porosity of commercial samples was lower than that of the elaborated samples. Texturally, it led to lower fracturability and greater fragility (less mm until fracture and fewer force peaks). The elaborated samples were all louder than the commercials. Although sensory analysis is required to classify a food as crunchy, the physicochemical changes caused by the substitution and their impact on the structure's behavior were established. Each textural parameter cannot determine whether the food is crunchy, crispy, or friable on its own; an analysis that incorporates all the characteristics is required. Supplement Material. PRACTICAL APPLICATION: This study demonstrates that pregelatinized cassava flour can be used to partially or completely replace wheat flour in baked snacks. Although textural differences were noted, these alterations were acceptable for products with a similar market niche. These findings might be used in the food business, notably by companies aiming to offer baked snack choices that are not made with standard wheat flour.

Purification and characterization of a fungal laccase expressed in Kluyveromyces lactis suitable for baking.

Laccase enzyme can replace chemical additives to improve texture properties and the volume of bread. Laccase encoding gene from Phlebia brevispora, a native fungus from Misiones, Argentina, was expressed in the generally recognized as safe yeast Kluyveromyces lactis. To improve laccase activity, medium conditions were optimized. The use of iron sulfate at a concentration of 1 mM led to optimum laccase activity (1289 U·L-1 ) on the fourth day of incubation. SDS-PAGE analysis revealed that the molecular mass of purified laccase was about 180 kDa. Optimum pH for the enzyme was 4 and optimum temperature was 40°C. Laccase exhibited high stability at low pH and high temperature. The application of recombinant laccase to bread decreased hardness, gumminess, and chewiness and increased bread volume. Based on these results, recombinant laccase from P. brevispora with improved yield is a good option for application as an improver of the physicochemical quality of bread at the industrial level. Besides, it will allow us to advance toward our goal of developing healthy alternatives for the bakery industry. No previous work has been reported concerning the heterologous expression of the laccase gene native to the province of Misiones, Argentina, with an aim for application in baking. PRACTICAL APPLICATION: Healthy bakeries became a trend in recent years. The use of the laccase enzyme increases the specific volume and decreases the hardness of bread, being thus an alternative for the replacement of chemical additives in the bakery industry.

Variation of color with baking time in snacks made with pregelatinized cassava.

Color is an importantaspect when formulating products, as the consumer will evaluate this aspect in the first instance. There is a growing interest in non-wheat producing regions to replace it with local sources of starches. However, the substitution of wheat flour affects characteristics such as texture, flavor, and color of the intermediate and final products. The objective of this work was to determine if the variation of the baking time allows reducing the color difference that the replacement of flour generates by dehydrated cassava puree (DCP). For that, four replacement levels were evaluated using the CIE-L * a * b * and CIE-L * C * H * methodology. The browning index and total color difference (ΔE) between samples with different replacement levels and between different stages of production were also evaluated. It was proved that the decrease in the baking time allowed the development of a similar coloring between snacks made with DCP and those made without substitution. Also, moisture values of less than 5% (dry basis) were obtained in the snacks. The browning index increased with the proportion of DCP in flour and doughs, but not in baked snacks. The pregelatinization of starches could be a mechanism to improve the quality of products with substitutions of wheat flour. PRACTICAL APPLICATION: Color is a critical attribute of foods in consumer acceptance. The accelerated color development that pregelatinized cassava starch produces in the appearance of baked goods can be useful for food development. A quick color development can mean shorter exposure time to heat, which is important for some products with heat-sensitive components. Also, it is interesting to note that the cassava dehydrated puree is a gluten-free product.