The Physicochemical, Textural, Microbiological and Sensory Properties of Skimmed Buffalo Milk Yoghurt with Tragacanth Gum During Storage.

Research background: In the food industry, research interest in the functional effects of natural polysaccharides from plants has increased in recent years. Tragacanth gum is used in dairy products because of its stabilising, thickening, fat-replacing and prebiotic properties. However, skimmed milk is considered a significant commercial loss in the production of buffalo clotted cream. Therefore, the aim of the present study is to investigate the potential of tragacanth gum in the production of yoghurt from buffalo milk residues with different concentrations of tragacanth gum (0.5, 1 and 1.5 g/L). Experimental approach: Skimmed buffalo milk with different concentrations of tragacanth gum was pasteurised and, after cooling at 45 °C, a starter culture was added to each sample. All samples were fermented to a pH=4.80±0.2. The gross composition, acidity, water activity, water-holding capacity, whey separation, mass fractions of organic acids and volatile aroma compounds, counts of total aerobic mesophilic bacteria, yeasts and moulds, Lactococcus spp. and Lactobacillus spp. as well as sensory and textural properties were analysed during 15 days storage. Results and conclusions: The results showed that the use of tragacanth gum increased the dry matter mass fraction, water-holding capacity and mass fraction of proteins in the samples, while whey separation decreased as the concentration of gum increased. The addition of gum improved textural properties and hardness of the yoghurt. In terms of consistency, the sample with 1 g/L tragacanth gum was the most reliable. In the control group, the total aerobic mesophilic bacteria count was highest on the first and last day of storage. According to the results of the sensory evaluation, the sample with 0.5 g/L tragacanth gum was the most favourable. Novelty and scientific contribution: Research has shown that the use of stabilisers in varying ratios improves the quality of yoghurt made from fat-free buffalo milk, which is a by-product of industrial production. So instead of ending up as industrial waste, it is recycled and its value is increased.

Physicochemical Characteristics, Phenolic Components, and Antioxidant Capacities of Lavender Honey (Lavandula Spp.) from Isparta Region of Türkiye.

Lavender honey is one of the most desirable blossom honeys for its unique taste and aromatic qualities and can vary significantly from one region to another. In this study, melissopalynological, physicochemical and antioxidant properties of lavender honey from the Isparta region of Türkiye were investigated. The ration of the Lavandula spp. pollen were identified ranging from 9 % to 76 % in the thirteen samples. The average pH, conductivity, moisture, Hunter Lab* and proline values were 3.72, 0.22 mS/cm, 17.17 %, L*: 66.56, a*: 66.32, b*:18.41 and 576.92 mg/kg, respectively. The average F+G and F/G were 67.66 % and 1.02, respectively. The average of total phenolic (TP) and flavonoid (TF) substance were found to be 39.40 mg GAE/100 g and 3.23 mg QUE/100 g, respectively. The average total antioxidant capacity (FRAP) and DPPH radical scavenging activity values were found to be 178.28 µmol FeSO4 ⋅ 7H2O/100 g and 53.09 mg/mL, respectively. In the phenolic component analysis performed with HPLC-PDA, p-OH-benzoic acid, p-coumaric acid, chrysin and pinocembrin were detected as common polyphenols in the samples. Conclusively, despite considerable variability in their monofloral characteristics, no significant differences were observed in the physicochemical and antioxidant properties of lavender honeys.