Journal of Food and Bioprocess Engineering
Volume:4 Issue: 2, Summer-Autumn 2021

This study investigated the possibility of developing a novel functional sesame paste based dessert bearing probiotic bacteria (Lactobacillus paracasei and Bifidobacterium lactis). Probiotics viability in the dessert as well as pH, acidity, texture and microstructure modifications were investigated during 28 days of cold storage. Cell viability investigation showed that the medium preserved cell viability above 106 CFU/mL during cold storage. The pH and acidity of inoculated desserts have been modified through storage. Flow behavior and texture analysis showed that desserts inoculated with B. lactis showed higher yield stresses and creep elasticity, due to the exertion of polysaccharides by the bacteria. L. paracasei exhibited lower pH values and reduced the creep viscosity and elasticity, due to changes in molecular interactions. Microstructure analysis of the samples showed that the oil was in the form of emulsion and proteins were dispersed in the continuous aqueous phase. According to the results of this study, it is concluded that the exploitation of mixed cultures in the dessert formulation could guarantee acceptable probiotic viability and provide better texture attributes.

In this paper, the response surface methodology is complemented with CFD simulation in order to study the optimization of the drying process of apricot slices. A Box-Behnken design was used. The studied factors were velocity of inlet air (A: 0.1-0.9 m/s), the porosity of apricots (B: 0.4- 0.6%), the temperature of inlet air (C: 20-60℃), and the time of drying process (D: 500- 3500 s). Then COMSOL software v. 4.1 was used to simulate the 25 runs derived from RSM design. The results showed the moisture content of samples in lower tray samples (L1-L5) was significantly (p < 0.01) higher than the upper tray samples (U1-U2). The uniformity of inlet air and temperature distribution has a great effect on the final quality of dried samples. Moreover, the inlet air temperature had a significant effect on moisture content. The interaction between the porosity of apricot, the two factors of the inlet air temperature and the drying time had a negative effect on the U-series response. But the best positive interaction effect was due to the air temperature and the drying time. These results show that the final quality is significantly dependent on the drying factors and the uniformity in temperature distribution in the cabinet dryer. The final optimum conditions for apricot drying were 0.6437 for parameter A (Velocity of inlet air), 0.5531 for parameter B (Porosity of apricot), 36.78 for parameter C (temperature of inlet air), and 3233.75 for parameter D (drying time).

The importance of using different medicinal plants indicates their health and valuable effects such as antioxidant, antimicrobial, anti-inflammatory effects and etc. In this research, the effect of alcoholic extract and essential oil of Syzygium aromaticum on Escherichia coli was investigated. The effect of the plant on this microorganism as a gram negative was evaluated and important indicator of poisoning and diarrhea at levels of 3, 4, 5, 6, 7, 8 and 9 mg/ml of broth culture media. By dilution method using liquid culture media, minimum growth inhibitory concentration and minimum bactericidal concentration were determined. The results of this study indicated increasing the concentration of extract and essential oil in the studied area increased their antibacterial effect and the most inhibitory effect was on essential oil which means that the minimum inhibitory concentration for ethanolic extract and essential oil was 8 and 6 mg/ml, respectively. Similar results were observed in relation to MBC. Also, by comparing the obtained results, it was deduced that the inhibitory effect of the essential oil used in this study on E. coli was greater than the clove extract and the essential oil of the cloves had a more antibacterial role than extract. Eugenol, eugenol acetate, cavicol and beta-caryophyllene were observed in GC-MS analysis and the difference in the content of bioactive ingredient eugenol further confirmed this antimicrobial effect.

Saffron flower waste is a new source of pectin and response surface methodology (RSM) was used to optimize the microwave-assisted acid extraction process. The optimal extraction conditions of pectin obtained from saffron flower waste were in microwave power of 700 W, irradiation time of 2.43 min, and pH of 1.5. The physicochemical and functional properties of pectin was evaluated and the results demonstrated that pectin extracted under optimal conditions was low methoxyl with emulsifying activity of 67.97%, surface activity of 36.89 mN/m and 33.24 mN/m at 0.10 and 0.50 % w/v, total phenolic content (TPC) of 2.86 mg EGA/g pectin and degree of esterification (DE) of 40.99%. In addition, the FT-IR and 1H-NMR spectra were used to identify the functional groups existing in the structure of extracted pectin.

This study investigated the effect of rainbow trout fillet's packaging (Oncorhynchus mykiss) on polyvinyl alcohol films that activated by silver nanoparticles; even though, it synthesized from aqueous extraction (Satureja rechingeri) with ultrasound and photochemical methods, increased the microbial shelf life (Antimicrobial properties) and qualitative properties of 160 piece of salmon alongside 4 kinds of packaging in 14 days at two refrigerator temperatures (4 and 8℃). The main compounds in Satureja rechingeri extract were carvacrol (83.2%), paracimene (3.11%), thymol (2.13%) and γ-terpene (1.63%). The evaluation of UV- VIS and TEM showed that diameter of S-AgNP was lower than 55 nm. According to this issue, the microbial load decreased in the sample of silver's nano covers that had ultrasound method (p > 0.05) and samples of nanosilver coating that had photo-chemical method; however, it had reduced effect on spoilage, also this process measured till fourteenth days of investigation. The results of this study showed we could use nanosilver's packaging of Satureja rechingeri aqueous for preserving raw and perishable foods such as fish. It is used to increase the shelf life and decrease the amount of spoil.

The present study reports the microencapsulation of extracts of saffron pollens containing polyphenolic compounds. Saffron pollen exhibit varying properties such as antioxidant and sensory properties and is also a source of many nutrients and bioactive compounds. In order to protect the polyphenols, the saffron pollen extract was microencapsulated by the spray drying method with maltodextrin as a carrier. Prior to encapsulation, the unbound water, total polyphenols contents and antioxidant activity of the extract was determined. The effect of inlet temperatures on the content of bioactive compounds, powder production yield, solubility and wettability was considered to study the spray drying process. The SEM images reveal that the produced microcapsules are spherical in shape. The results showed that the total polyphenol content of saffron pollen extract was found to be 620 ± 4.50, 470 ± 2.65, 420 ± 2.18 mg gallic acid per g, for 140, 160 and 180 , respectively and spraying drying could significantly maintain the polyphenolic content as well as the antioxidant capacity of extracts. The IC50 results for saffron pollen extract was found to be 0.177 ± 0.08, 0.191 ± 0.09, 0.182 ± 0.08 g per 100 g, for 140, 160 and 180 , respectively. The best temperature for this purpose with the highest solubility and wettability of the powder is the inlet temperature of 140  and Outlet temperature of 85 , thus have potential applications in food and pharmaceutical products.

The aim of this study was to use two probiotic strains, Lactobacillus rhamnosus and Lactobacillus casei, in order to produce a functional fermented camel milk drink with anti-Helicobacter pylori activity. During a 35-day storage period, chemical (pH and acidity contents), sensory characteristics, and Helicobacter pylori inhibitory activity of fermented camel milk samples have been investigated; Helicobacter pylori activity was examined using the Berthelot Method. At the end of the cold storage period, the lactic acid bacteria count was acceptable for probiotic products. Camel skim milk and fermented milk samples showed promising Helicobacter pylori inhibitory activity. The IC50 results from this study were IC50 = 24.58 and IC50 = 55/73 M).Specific inhibition or reduction of urease enzyme activity would result in an increased sensitivity of the bacteria in an acidic medium, and therefore, it can be considered a new functional food for stomach problems.

In this study, the effect of different amounts of konjac gum (KG) (0 to 0.2%) and sage seed gum (SSG) (0 to 0.2%) as experimental variables of the mixture design and fat content (0 to 3%) and homogenization rate (0 to 24000 rpm) as experimental variables of the process design on the viscoelastic characteristics of low-fat stirred yogurt were investigated. Based on the results of stress sweep test for different samples, the storage modulus (G') had a value more than the loss modulus (G''), explaining a solid-like behavior of the samples. Also, according to the stress sweep test, G' LVE (G' at linear viscoelastic region), G'' LVE (G'' at linear viscoelastic region), γc (critical strain), τy (yield stress), τf (yield stress at flowing point), and Gf (elastic modulus at flowing point) of the samples were significantly increased, especially for samples containing higher sage seed gum, with increasing fat content and homogenization rate. To optimize the properties in this study, G" LVE were considered to be minimum and G' LVE, γc, τy and τf were considered to be maximum. According to the mentioned properties, the optimized amount of KG was 0.19%, the amount of SSG was 0.01%, the fat content was 0.59% and the homogenization rate was 12075 rpm.

Effects of pretreatments (blanching, air-drying, osmotic dehydration and freezing) and process parameters: frying temperature (100, 110 and 120°C) and frying time: (180, 300 and 420 s) at constant vacuum pressure of 70 mbar on some quality characteristics of vacuum fried onion chips (oil uptake, shrinkage, breaking force, and total color difference) were studied. The results showed that frying temperature and frying time at all pretreatments had a significant effect (p ≤ 0.05) on oil uptake and shrinkage, as well as total color difference and breaking force of vacuum fried onion chips. The results demonstrated that the oil uptake, shrinkage and total color difference of the fried onion chips increased, while breaking force decreased with increasing frying temperature and time. The results showed that the different pretreatments before vacuum frying influenced significantly (p ≤ 0.05) the quality characteristics of vacuum fried onion chips. At the same frying temperatures and frying times, the lowest oil uptakes were observed in osmotic dehydrated samples, followed by air-dried and then blanched samples. Freezing pretreated onion samples show the highest o oil uptake (p ≤ 0.05) than other pretreatments. Freezing pretreatment resulted in minimum shrinkage, compared to other pretreatments (p ≤ 0.05) followed by osmotic dehydrated samples. Shrinkage in air drying and blanching pre-treated samples did not differ significantly. Osmotic dehydration pretreated onion samples show less breaking force (p ≤ 0.05) than other pretreatments followed by air-dried pretreated onion samples while blanching and freezing pretreatment resulted in minimum crispiness. At the same temperatures and frying times, the lowest levels of total color difference were observed in blanched samples, followed by osmotic dehydrated and then the air-dried samples.  Freezing pretreated onion samples show the highest levels of total color difference (p ≤ 0.05) than other pretreatments.

Detoxification of solution and beer from aflatoxins B1 and G1 using layered double hydroxides is the focus of this study. The aluminum-magnesium layered double hydroxide (Al-Mg LDH) is selected in its calcined and non-calcined forms to evaluate the influence of calcination on detoxification. They were produced using the co-precipitation method and used in contaminated solutions and beer. Characteristics of the adopted adsorbents were studied by XRD, FTIR and SEM methods. Effects of quantity of the adsorbents, exposure time, and initial content of aflatoxin were investigated. Moreover, effects of the adsorbents on the properties of beer were studied. The non-calcined form of Al-Mg LDH was not able to adsorb aflatoxins B1 and G1 considerably. On the opposite, its calcined form exhibited more than 90% adsorption just in less than one hour in solutions and in less than 4 hours in the beer samples. The reason is pointed to the fact that calcination of Al-Mg LDH considerably enhanced characteristics of the adsorbent. It almost doubled surface area of the material, increased its total pore volume over 54%, and added to its pore size over 35%.

The fermented whey protein concentrate (FWPC) and whey permeate (WP) at the levels of 0 (control), 25, 50, 75 and 100% were separately substituted instead of water (v/v) used for dough preparation in bread loaf making. The effect of incorporation of WP or FWPC was measured on dough properties (falling number, dough handling and water absorption) and bread making quality (loaf volume, loaf height, specific volume and baking loss). The results clearly showed that incorporation of increasing amount of WP and FWPC had contrary effect on falling number and significantly reduced and increased falling number values, respectively. Incorporation of WP and FWPC at increasing levels during dough preparation showed significant increase in water absorption in comparison to control and handling of dough for all treatments was smooth except for samples contain 100% FWPC which the dough was slightly sticky. Increasing WP up to 50% increased volume, height and specific volume of loaves (p>0.05) and thereafter slightly reduced it, while increasing the level of FWPC, except at level 25%, progressively decreased these parameters (p < 0.05). Independent of whey type (WP or FWPC) and incorporation levels, baking loss of bread decreased significantly with WP or FWPC fortification compared to the control, indicating higher moisture retained in supplemented breads. Based on results of this study, by incorporation of 50% WP or 25% FWPC, a loaf bread could be produced with the appropriate dough properties (with smooth and flexible texture) and baking qualities (acceptable loaf volume and baking loss).

Cardiovascular disease (CVD) is the leading cause of death in the world. Hypercholesterolemia, characterized by elevated blood low-density lipoprotein cholesterol (LDL-C) concentrations, is a risk factor for CVD. A growing body of research suggests that LDL-C levels and CV risk are linked. Despite the fact that the majority of current epidemiologic studies show no substantial link between eating one egg per day and blood cholesterol levels or cardiovascular risk, proponents of a positive link remain. The goal was to look at intervention trials that looked at the impact of cholesterol on LDL levels in people. In addition, eggs and dietary cholesterol affect serum cholesterol in many ways. The importance of decreasing cholesterol levels with probiotics, dietary fiber, plant sterols, and nutraceuticals was also discussed.