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Jerusalem artichoke tubers (Helianthus tuberosus) are distinguished by their protein, minerals (potassium, calcium, magnesium, iron, etc.) and inulin content. Inulin can be used in the diet of diabetics as a substitute of sugar, without having an impact on blood glucose. At the same time, an international study had shown that due to their inulin content, regular consumption of Jerusalem artichoke tubers can help to prevent type 2 diabetes. In this paper are presented the results of the researches performed to achieve a functional ingredient (powder) with high nutritional value by processing of Jerusalem artichoke tubers. Thus, the Jerusalem artichoke tubers (Red Jerusalem artichoke and White Jerusalem artichoke varieties) were subjected to a convective drying process at 50°C, to protect bioactive components (vitamins, phenolic compounds, etc.) to a moisture content that allow their milling and turning them into powder and, at the same time, their stability in terms of quality. The achieved functional ingredient was evaluated sensory, physicchemically and microbiologically. The powder obtained from Jerusalem artichoke tubers is characterized by their inulin-type fructans (51.60... 57.45%), crude fiber (6.85...8.27%), total polyphenols (18.51... 44.03 mg GAE/g), proteins (8.75...9.26%), iron (12.45...13.88 mg/100g), potassium (1905.44...2100.35 mg/100g), calcium (50.21...57.45mg/100g), magnesium (84.55...89.95mg/100g) and phosphorus content (300.12...345.35 mg/100g). At the same time, powder achieved from Jerusalem artichoke tubers has antioxidant potential. Due to its complex biochemical composition, the functional ingredient achieved from Jerusalem artichoke tubers can be used to fortify food and also as a sweetening agent for products destined to diabetics.

Yeast (including brewing yeast) and yeast-based preparations derived from bioprocesses or agroindustrial byproducts represent valuable feed additives and ingredients for ruminants. The optimization of brewing yeast biotechnological processing through fermentation mediated by the brewing yeast strain Saccharomyces pastorianus ssp. carlsbergensis W34/70 was investigated. The cultivation conditions (temperature, pH, carbon source, and nitrogen source) were selected and designed according to a Taguchi fractional experimental plan, with four factors on three levels, and their influence on the evolution of the bioprocess of obtaining the brewing yeast biomass was evaluated. The dependent variables were the yeast biomass amount in wet form, yeast biomass amount in dried form after lyophilization, dried yeast biomass wettability assayed through the contact angle (CA), protein content (PC), and dry matter content (DS). The effects that the experimental conditions had on the system responses were visualized in tridimensional space using the response surface methodology, and the combination of biotechnological parameters that ensured process quality and robustness was then determined using the Taguchi technique through its performance indicator, i.e., the signal-to-noise ratio. By optimizing the biotechnological parameters, this study provides a valuable contribution in the area of brewing yeast biomass processing, with the aim of producing probiotic yeast for ruminant nutrition.