Seed priming with plant growth-promoting bacteria (PGPB) improves growth and water stress tolerance of Secale montanum

Assessment of the Suitability of Flour Obtained from Mountain Rye Grain Milling and the Method of Dough Fermentation for the Production of Rye Bread

Currently, there is an increase in consumer interest in food produced from raw materials from organic farming, which has an impact on the greater attention paid to the possibility of increasing the cultivation of old cereal species. One of the cereals that is suitable for these trends is mountain rye, which is a premise for undertaking research on the usefulness of this cereal grain in food production. Therefore, the aim of the study was to compare the baking value of flour with different milling yields obtained from milling mountain rye grain. The research material consisted of rye grain (Secale montanum Guss.), which was milled, and 6 different rye flours were obtained. The flour was tested for selected quality parameters such as moisture, crude protein content, total ash content, and acidity. Doughs were prepared and fermented using a single-phase method carried out in two different variants, with or without the addition of lactic acid. The obtained rye breads were quality assessed and subjected to organoleptic and consumer evaluations. The use of the fermentation method with dough acidification with lactic acid allowed us to obtain breads with a better specific volume and acidity compared to those obtained from dough without acidification. Breads baked from dough prepared using the method of non-acidification with lactic acid had better porosity of the crumb. In the quality classification, breads made from low-extract flour turned out to be the best, and breads baked from dough made using the non-lactic acid acidification method were more generally accepted by panelists. As confirmed by research, mountain rye grain is a raw material for the production of flour with good baking value, which depends on the preparation of the grain and milling method. The quality of rye bread made from mountain rye flour depends on the flour yield, the baking value of the flour, and the method used for dough fermentation for bread baking.

Comparison of the Antioxidant and Sensorial Properties of Kvass Produced from Mountain Rye Bread with the Addition of Selected Plant Raw Materials

Consumers' growing awareness of healthy nutrition results in an increase in demand for the production of beverages with health-promoting properties. An example of such a product is kvass produced in the fermentation process. This research aimed to determine the impact of plant additives on the antioxidant and sensorial properties of kvass made from bread based on mountain rye flour. The bread extract was fermented at different temperatures (28 and 34 °C). Additives of 3, 5, and 10% were used in the tests, which included black chokeberry juice and infusion, sea buckthorn fruit juice and infusion, and peppermint leaf infusion. A higher fermentation temperature in the production process resulted in an improvement in the organoleptic and antioxidant properties of the tested kvasses. The highest antioxidant activity was demonstrated by kvass with the addition of 10% black chokeberry juice (0.734 µmol Trolox g-1 (ABTS), 4.90 µmol of Trolox g-1 (DPPH)), and a peppermint leaf infusion (0.773 µmol Trolox g-1 (ABTS), 4.71 µmol Trolox g-1 (DPPH)). The conditions of kvass production and the type and amount of the additive influenced the selected physicochemical parameters of the obtained kvasses. The chromatographic analysis confirmed the content of 13 phenolic compounds in kvass with the addition of black chokeberry juice, which was 1.68-1.73 mg/100 mL of the finished product with a 10% share of the additive. The 11 phenolic compounds in kvass with the addition of peppermint infusion were confirmed for 7.65-6.86 mg/100 mL of the finished product with 10% of the additive. Kvass enriched with additives from black chokeberry fruit and peppermint leaves may be a promising new category of functional beverages with health-promoting properties resulting from the content of polyphenol compounds. It could be a better base for enrichment with raw materials that are richer in these compounds than pasteurized products.

Microbiome engineering optimized by Antarctic microbiota to support a plant host under water deficit

Climate change challenges modern agriculture to develop alternative and eco-friendly solutions to alleviate abiotic and/or biotic stresses. The use of soil microbiomes from extreme environments opens new avenues to discover novel microorganisms and microbial functions to protect plants. In this study we confirm the ability of a bioinoculant, generated by natural engineering, to promote host development under water stress. Microbiome engineering was mediated through three factors i) Antarctic soil donation, ii) water deficit and iii) multigenerational tomato host selection. We revealed that tomato plants growing in soils supplemented with Antarctic microbiota were tolerant to water deficit stress after 10 generations. A clear increase in tomato seedling tolerance against water deficit stress was observed in all soils over generations of Host Mediated Microbiome Engineering, being Fildes mixture the most representatives, which was evidenced by an increased survival time, plant stress index, biomass accumulation, and decreased leaf proline content. Microbial community analysis using 16s rRNA gene amplicon sequencing data suggested a microbiome restructuring that could be associated with increased tolerance of water deficit. Additionally, the results showed a significant increase in the relative abundance of Candidatus Nitrosocosmicus and Bacillus spp. which could be key taxa associated with the observed tolerance improvement. We proposed that in situ microbiota engineering through the evolution of three factors (long-standing extreme climate adaption and host and stress selection) could represent a promising strategy for novel generation of microbial inoculants.