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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.

Pickling cucumbers are highly important both for fresh consumption and for canning industry. This study aimed to compare differences in yield and quality of eight pickling cucumber cultivars, including ‘Cor 12004’, ‘IGG 2010’, ‘IGG 2020’, ‘SM 5322’, ‘SM 5323’, ‘Zayin 201’, ‘Zayin 175201’ and ‘Trilogy’. The cucumber cultivars were laid out in a high tunnel crop and evaluated for vegetative traits (i.e. vine length, nodes per vine and branches per vine), yield attributes (i.e. fruits per main stem, average weight of fruit and fruits weight per plant) and fruits quality components (nitrate, phosphate and potassium mg kg-1). The results showed significant differences (P12 cm), revealed a declining value with increase in the cucumber length. The study findings suggest that irrespective of the cultivar, the amount of nitrate was higher in shorter cucumbers (6-9 cm length) although allrecorded values (between 192.7 and 364.3 mg kg-1 fresh matter) being under maximum accepted limit concentrations. The amount of phosphate was higher in medium to long cucumbers, while the amount of potassium was higher in shorter cucumbers.