Search

Fungal agents emerged as post-pasteurization contamination are responsible for the spoilage in yogurt drink. In this work, the antifungal effects of some lactic acid bacteria (LAB) on the spoilage yeasts isolated from yogurt drink (Doogh) were evaluated. First, the microbial growth in the yogurt drink samples during the storage time was investigated, and the isolated microorganisms were identified using biochemical methods and sequencing of the specific amplicons. Yeasts (3-7 log CFU ml

Pomegranate juice (PJ) (at concentrations of 13% and 17%) was added to yogurt and its physicochemical and microbial properties were investigated. PJ improved several features of yogurt, bringing an increase in total phenolic contents by 4.3–6.1 and 5.3–7.3 fold in response to 13% and 17% PJ, respectively. Also, there were increases in the total anthocyanin contents of yogurt by 2650–2870 and 3470–3820 fold in response to the said juice concentrations. These increases were observed in both set and stirred yogurts, whereas IC50 values of the yogurts decreased by 2.2–2.6 and 3.0–3.3 fold, respectively, compared to the control samples. Total acidity, syneresis, and redness value of the yogurts increased, parallel to the increase in the PJ concentration being added. Also, Streptococcus thermophilus count decreased significantly, whereas no significant effect was observed on the population count of Lactobacillus delbrueckii subsp. bulgaricus. Among PJ yogurt samples, the panelists selected the 13% PJ stirred yogurt as the best sample. PJ was observed to contain valuable bioactive compounds with functional and medicinal effects that culminate in health benefits., The addition of bioactive compounds, such as polyphenols, flavonoids, and anthocyanins, to the yogurt can make it healthier. Pomegranate juice is a valuable source of natural antioxidants, especially for its phenolic compounds, and can be added to the yogurt for improving its functional properties and to fulfill consumer expectations. The objective of this study was to optimize pomegranate juice concentrations (13% and 17%) by adding them to the yogurt, followed by an analysis of its physicochemical features and microbial properties.

High consumption of processed red meat can cause health issues. Therefore, production of high-quality meat-free food alternatives is necessary. The main objective of this study was to use hydrocolloids including kappa-carrageenan, konjac mannan and xanthan gum at 0, 0.3, 0.6, 1.0 and 1.5% w/w to improve the quality of meat-free sausages formulated by soy protein isolated, texturised soy protein, corn starch, vegetable oil and spices. With the addition of the tested hydrocolloids, the lightness of the sausages improved. kappa-Carrageenan and konjac mannan significantly improved the water-holding capacity and texture and reduced the cooking loss of the samples, while xanthan gum showed no considerable effect on these parameters. Konjac mannan and kappa-carrageenan (up to 0.6%) improved the general acceptability of the sausages, while inclusion of xanthan gum made no significant difference. Unlike xanthan gum, kappa-carrageenan followed by konjac mannan was highly successful in improving the overall quality of meat-free sausages.

In this study, complete block cryoconcentration of pomegranate juice was investigated. Two freezing temperatures (−20 ± 1C and −40 ± 1C), two thawing modes (gravitational-assisted thawing and microwave-assisted thawing) and four cryoconcentration stages were the process variables. Total dry matter content, process efficiency, pH and color values (L, a, b and ΔE) of cryoconcentrated and ice fractions were investigated. In addition, pomegranate juice concentrate was produced by conventional thermal processes, namely evaporation by rotary vacuum evaporator and by heating at atmospheric pressure to compare the color values and pH of final cryoconcentrated pomegranate juice with those of thermally produced juice concentrates. Freezing temperature and thawing mode did not have any significant effect on the total dry matter content of cryoconcentrated and ice fractions as well as process efficiency, pH and the color values (P > 0.05). However, the results indicate that cryoconcentration stage had a significant effect on dry matter content, process efficiency and the color properties of both fractions (P > 0.05). The final dry matter content of pomegranate concentrate reached 34.20 ± 0.13% from the initial value of 17.16 ± 0.68%. The change in the pH of final cryoconcentrated pomegranate juice was less than the change in the pH of thermally produced juice concentrates. This study showed that the color characteristics of pomegranate juice were well preserved by complete block cryoconcentration process in comparison to conventional thermal processes. Practical Applications Concentration of fruit juices is one of the oldest methods by which the shelf life of fresh products can be extended significantly. Concentration of fruit juices by means of thermal process is proved to induce adverse effects on sensory and chemical properties of them. Cryoconcentration technology is introduced as a suitable technique for concentration of liquid foods and nutraceuticals because it can preserve the nutritional and sensory qualities of the products while it is a green technology. Because pomegranate juice is a valuable source of bioactive compounds that are responsible for its appropriate color, cryoconcentration process has high potential for preserving its nutritional and sensory properties during concentration process.

The influence of drying air temperatures, drying air flow rate and feed flow rate on percentage survival rate (% SR) of starter and probiotic bacteria, moisture content, water activity and colour of probiotic yoghurt powder produced using a pilot-scale spray dryer was investigated. Optimisation of spray drying conditions was achieved based on the desirability value. Results showed that inlet air temperature, drying air flow rate, feed flow rate and outlet air temperature of 150 °C, 478 m3/h, 2 L/h and 63.3 °C, respectively, were optimal conditions to produce powder that meets quality specifications and with a satisfactory% SR.

In this study, the influence of the application of 0.025%, 0.05% and 0.075% of Zataria multiflora Boiss. essential oil (EO) on oxidative stability of sunflower oil was examined and the EO was compared to butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) during storage at 37°C and 47°C. The main components of EO were identified as carvacrol (45.6%), p-cymene (18.1%) and thymol (16.3%). Peroxide value (PV), anisidine value (AnV) and thiobarbituric acid (TBA) value measurement in sunflower oil showed that all concentrations of EO had a lower antioxidant effect in comparison to BHA and BHT. Samples supplemented with EO concentration of 0.075% were the most stable during storage at both temperatures (p