A Box‐Behnken design was applied to optimise the viability of Lactobacillus acidophilus and Bifidobacterium bifidum in probiotic yoghurt containing a novel exudative Zedo gum. The effect of incubation temperature, probiotic inoculation rate, storage time and Zedo gum concentration on quality indices of the yoghurt were explored. With respect to probiotics viability, probiotic inoculation rate was the most important factor followed by the storage time. Zedo gum did not show any significant effect on probiotics viability. The optimum conditions of probiotic yoghurt production were as follows: probiotic inoculation level, 12.8 g/100 kg of milk; incubation temperature, 41.6 °C; and Zedo gum concentration, 0.13%.

Today, the usage of natural additives in the food matrix has increased. Natural antimicrobial compounds include peptides, enzymes, bacteriocins, bacteriophages, plant extracts, essential oils, and fermented compounds that can be used as alternatives to chemical antimicrobials. Plant extracts and essential oils contain terpenes, flavonoids, aldehydes, and phenolic compounds that cause antimicrobial and antioxidant activity. The synergistic activity of compounds synthesized from lactic acid bacteria (LAB) prevents the growth of bacteria and fungi. In addition to removing mycotoxins, LAB compounds have antioxidant and anticancer potentials and increase food safety and nutritional value. One of these antimicrobial molecules is bacteriocin, which is made by various microorganisms. Nisin is one of these bioactive peptides that are used widely in food bio-preservation. Antimicrobial peptides can be used alone or along with other compounds to enhance food security. This article reviews natural preservatives and their applications in food products.

Despite the unique properties, application of garlic essential oil (GEO) is too limited in food and drugs, due to its low water solubility, very high volatility and unpleasant odour. In this work, a nanoemulsion containing GEO was formulated to cover and protect the volatile compounds of GEO. The encapsulation efficiency of formulated nanoemulsions was measured by gas chromatography and obtained encapsulation efficiency ranged from 91 to 77% for nanoemulsions containing 5-25% GEO, respectively. The 2,2-diphenyl-1-picrylhydrazyl method for antioxidant activity measurement showed that free radical scavenging capacity of nanoemulsions intensified during storage time. The electrical conductivity of the samples was constant over storage time while linearly increased by raising the temperature. Thermogravimetric analysis was used to determine the thermal resistance of nanoemulsions and their ingredients. Interestingly, microbial tests cleared that the control nanoemulsion with a particle size below 100 nm (nanoemulsion without GEO) also showed antimicrobial activity. Disk diffusion method showed that pure GEO and also formulated nanoemulsions had a stronger effect against Gram-positive bacterium () than Gram-negative bacterium ().

No abstract

In this study, using a central composite design, the effects of addition of Spirulina platensis and Zedo gum to plain and probiotic yoghurt samples were investigated during storage. Lactobacillus paracasei proliferation was directly dependent on the addition of microalgae and was inversely affected by storage time. Probiotic samples containing S. platensis showed the highest antioxidative activity. Maximum stability was obtained at higher amounts of Zedo gum, while organoleptic and rheological attributes improved at 0.25% Zedo gum. Given the importance of probiotic viability, supplementation of probiotic yoghurt with Zedo gum/S. platensis may be consideredas a novel nutraceutical formulation.