The present research investigates the effect of different pretreatments on glucose and fructose consumption and ethanol production by four Saccharomyces cerevisiae wine strains, three isolated and identified from different wine regions in Turkey and one reference strain. A mild stress temperature (45 °C, 1 h) and the presence of ethanol (14% v/v) were selected as pretreatments applied to cell cultures prior to the fermentation step in synthetic must. The goodness fit of the mathematical models was estimated: linear, exponential decay function and sigmoidal model were evaluated with the model parameters R² (regression coefficient), RMSE (root mean square error), MBE (mean bias error) and χ² (reduced Chi-square). Sigmoidal function was determined as the most suitable model with the highest R² and lower RMSE values. Temperature pretreatment allowed for an increase in fructose consumption rate by two strains, evidenced by a t90 value 10% lower than the control. One of the indigenous strains showed particular promise for mild temperature treatment (45 °C, 1 h) prior to the fermentation step to reduce residual glucose and fructose in wine. The described procedure may be effective for indigenous yeasts in preventing undesirable sweetness in wines.

Contemporary customers have increasingly heightened demands regarding their dietary preferences, favoring readily available and healthful ready-to-consume food and beverage alternatives. In order to fulfill this demand, the beverage industry has been exploring innovative products. Red beetroot juice (RBJ) is easily consumed and offers a beneficial advantage due to its betalain content. Both the traditional/spontaneous method and the industrial method are viable options for producing RBJ. The aim of this study was to examine the stability of betalains, the primary bioactive component in RBJ, throughout the fermentation process and during storage. The RBJ samples contained betalain pigments, as indicated by the infrared spectra. No decrease in betalain content was observed in either RBJ juice fermented by two different methods. The total betalain content of the RBJ samples was 594.068 and 535.152 mg/L at the beginning of fermentation through the spontaneous method and the method with the addition of Lacticaseibacillus paracasei 431 (Lc. paracasei), respectively, and 580.151 mg/L and 667.382 mg/L at the conclusion of fermentation, respectively. Mathematical models were employed to represent the degradation of betalains over time during storage. It was found that the sigmoidal model (R2 = 0.974) and other models (R2 = 0.957–0.969) demonstrated a greater potential to describe the degradation of betalains in RBJ samples produced by the spontaneous method compared to the first-order kinetics model (R2 = 0.932). The models used in the study were successful, with R2 values ranging between 0.927 and 0.932 in the RBJ samples produced with the addition of the probiotic Lc. paracasei for predicting betalain degradation.

This study examined the effect of different plant powders on the technological and nutritional qualities of gluten-free bread. As plant powders, fenugreek, okra, and quince seeds were used both separately and in combination. According to technological properties, the greatest increase in the breads’ height and specific volume values occurred in the samples coded HD2 (100% okra powder) and HD7 (33.3% fenugreek, 33.3% okra, and 33.3% quince seeds powder) (P < 0.05). Scanning electron microscope images revealed that the addition of plant pow-der increased the porosity of bread samples, particularly in HD2, HD6 (50% okra and 50% quince seed powder), and HD7 samples. All samples enriched with plant powders exhibited higher levels of dietary fiber (DF), ranging from 5.95±0.48% to 6.97±0.4%, compared to the control sample, which had a level of 4.45±0.22% (P < 0.05). Incorporation of 100% fenugreek (HD1 sample) resulted in a substantial elevation of the resistant starch value. This feature was considered beneficial for nutrition because it could lower the glycemic potential of bread. Enrichment with okra powder provides nutritious and technologically advantages to gluten-free breads. Panelists provided the least score for fenugreek addition, while the samples containing okra powder received greater acceptance.

The present study aimed to optimize the production conditions of a beetroot-based beverage using Lacticaseibacillus paracasei. The experiment was meticulously planned and executed using the Box–Behnken design in Response Surface Methodology (RSM), which provided 17 different combinations. The independent variables in this study included the heat treatment temperature (60–80℃, the heat treatment time (10–30 s), and the incubation temperature (24–36℃). The variables evaluated in this study included pH, total acidity (TA), total phenolic content (TPC), total betalain content (TBC), yellow color (OD420), general acceptance (GA), and total count of lactic acid bacteria (LAB). The samples were determined to have TPC ranging from 67.90 to 437.15 mg GA/L and TBC ranging from 147.52 to 747.21 mg/L. The samples subjected to incubation temperatures of 30℃ and 36℃ were typically favored by the panelists and exhibited better results in terms of chemical analysis compared to the samples incubated at 24℃. According to RSM, heat treatment at 60℃ for 22 min and an incubation temperature of 31℃ were the optimum production conditions. Under these optimal conditions, RBJ has maximum TBC, total LAB, and GA scores, indicating nutrient-dense and appealing to consumers.