Influence of storage on chemical, microbial and consumer acceptability of a milk-like product made from melon seeds

Preservative Effect of an Antimicrobial Substance from Bacillus subtilis fmbJ on Pasteurised Milk During Storage

Bacillus subtilis fmbJ was found to produce an antimicrobial substance, which exhibited inhibitory activity against food spoilage microbes and pathogens. The inhibitory effect of the antimicrobial extracts on two Gram-positive bacteria, seven Gram-negative bacteria and five moulds had been identified. Pasteurised milk samples with different concentrations of the antimicrobial substance ranging from 0 to 2mg/mL were stored at 4°C and 20°C. The preservative effect of the antimicrobial substance on pasteurised milk was evaluated. The result indicated that 0.25-2.0mg antimicrobial substance per mL can reduce significantly mesophilic bacteria in milk by 1-4log units at 20°C, and 1-5log units at 4°C after 15 days storage compared with control milk. Under the same experimental conditions, sensory quality of pasteurised milk with added 0.25-2mg antimicrobial substance per mL could remain acceptable for 6-15 days at 20°C and 9-15 days at 4°C.

Spray dried melon seed milk powder: physical, rheological and sensory properties

Melon seed milk (MSM) powder was produced by aiming to get alternative vegetable milk from crushed Kırkağaç (Cucumis melo subsp. melo cv. Kırkağaç) and Çeşme (C. melo subsp. melo cv. Çeşme) type melon seeds. MSM was converted to powder form via spray dryer at inlet air temperature of 150 °C, air flow rate of 473 l · h(-1), aspiration ratio of 24 m(3) · h(-1)and feed flow rate of 8 ml · min(-1) in order to extend the shelf life and usage area. The moisture content and water activity of samples changed in range of 2.1 to 2.4 % and 0.260 to 0.310, respectively. Bulk densities and the tapped densities of powders were ranged from 340 to 360 kg · m(-3) and 730 and 740 kg · m(-3). MSM powders showed poor flow behavior as determined from Carr Index. The particle densities of powders ranged between and 1069 kg · m(-3). Wettability time of powders was found as 7 s. The Bingham model was the best model fitted to rheological data of MSM beverages. Sensory evaluation test results showed that, the beverage obtained from reconstituted Kırkağaç powder achieved the highest score by panelists.