Journal of Food and Bioprocess Engineering
Volume:1 Issue: 1, Winter-Spring 2018

The tremendous mounting interest in lipase production is pertinent to the biotechnological applications that these enzymes offer. Lipase, belonging to the hydrolyze enzymes, is involved in copious biological functions including: hydrolysis insoluble triacylglycerol to mono and diacylglycerols and glycerol. Submerge fermentation technique was applied for the efficient production of this. Briefly, olive oil emulsified by Arabic gum (3% olive oil with 8% Arabic gum) and coriander seed extract (7%) were used as supplementation. Extract was isolated from the olive used to isolation lipase producing bacteria. Among the isolates, mesophilic OE3 strain was selected as the best lipase producing bacterium with high hydrolytic activities (663U/ml). From Rhodamin B, we applied agar plate technique to screen lipase production bacteria based on e formation of the fluorescence halo around the colony under radiation of UV. The isolate was short rod- and coccoid-like. The isolate was Gram-positive, aerobic, non-motile, non-endospore-forming, non-acid fast, oxidase-negative, and catalase-positive. The selected isolate was positive for H2S and indole production and urea hydrolysis; however, they could not reduce nitrates to nitrogen. The final achievement was a lipase activity 2645 U/ml after 48 h incubation in 37ºC.

Nowadays polymer nanocomposites have introduced as a new class of food packaging materials due to their enhanced mechanical, thermal, and barrier properties. In this study PET nano composites were prepared by melt blending of poly (ethylene terephthalate) pellets and mica nanoparticles. The morphology of PET/mica nanocomposites was characterized by X-ray diffraction and transmission electron microscopy (TEM), showing exfoliated/intercalated structures for different concentrations of mica. The crystallization behavior was studied by differential scanning calorimetry (DSC). Incorporation of mica nanoparticles in PET matrix had pronounced effect on crystallization of poly (ethylene terephthalate). Both crystallization rate and degree of crystallinity increased due to nucleation effect of mica nanoparticles. The results of mechanical test indicated that addition of micas to PET matrix caused to slight diminish of tensile strength and ductility of polymer.

Rivers can be contaminated with different pollutants such as trout farms. Evaluation of the effect of trout farm on water quality is important to give new permission for trout farm construction. In current work, the effect of constructed trout farms near the Deinachal River on some physicochemical properties namely chemical oxygen demand (COD), biological oxygen demand (BOD5), dissolved oxygen (DO), pH, temperature, turbidity, nitrate, nitrite, phosphate, heavy metals, total hardness, total alkalinity, calcium, magnesium, electrical conductivity, fecal coliform and ammonium were studied and the water quality was classified using Iran Water Quality Index (IRQWI). Results showed that except nitrite, ammonium, chromium, nickel, lead, cadmium and mercury, other parameters affected by both trout farms and domestic wastewater. However, assimilative capacity of Deinachal River due to entrance the branches into the river can improve the water quality.

In this research, the chemical and microbiological characteristics of white brined cheeses produced with five different starter cultures, namely: traditional kefir grain, commercial kefir, commercial yogurt, traditional yogurt and commercial cheese starter culture, were examined during 60-day ripening period. Results of statistical analysis showed that the type of starter culture had a significant effect on pH, acidity, fat, protein, moisture, enterobacteria, total counts, mold and yeast as well as on lactococcus (p < 0.01), and lactobacillus level (p < 0.05). pH, acidity, fat, protein, total count, mold and yeast, and lactobacillus level (p < 0.01) were significantly affected by starter culture type during ripening period. However, moisture, enterobacteria and lactococcus level in all cheese samples were not affected by ripening period. Whereas other parameters including pH, fat and protein content showed decreasing trend during ripening. Among chemical analyses, cheese produced with traditional kefir had highest pH and cheese produced using commercial kefir showed highest acidity and moisture. Among microbial parameters cheese produced with commercial kefir starter had the lowest total microbial count and after that cheese using traditional kefir starter. It is concluded that traditional kefir grain can be used as a starter culture in production of functional white brined cheese.

The effect of different extraction rates (64%, 82% and 90%) of wheat flour on the rheological properties of the wheat flour dough was investigated. A complete study of the rheological behavior of the wheat flour dough was performed by using three different instruments namely alveograph, extensograph, and farinograph. The correlation coefficient among the various parameters of applied methods was also determined and the most suitable method in assessment of flour attributes recognized. The lower bran concentration (extraction rate 64%) in flours showed the better pronounced effect on dough properties yielding strengthened dough. Several expected associations were found among applied methods, in spite of the fact that no significant correlation among all parameters of the methods was observed, some parameters of the measuring methods had very strong correlation (p<0.01) that included farinograph water absorption, tenacity (P), extensibility (L), P/L, swelling index (G) of alveograph, energy and the resistance to constant deformation after 50 mm stretching (R50) of extensograph. Among the applied methods, most of the alveograph parameters had significant correlation ( , p<0.01) together and it might be used as the recommended method to assess dough rheology.

In this work the chemical composition and antimicrobial activity of Pelargonium roseum leaves essential oil that grown in southwest of Iran were determined. The hydrodistilled volatile components were identified by GC/MS analysis. A total of 33 components have been identified in the oil, representing 99.38% of the total oil and citronellol (44.63%), citronellyl formate (14.22%), isomenthon (6.34%), geraniol (5.30%) and caryophyllene (3.55%) were the main components, respectively. Antimicrobial property of essential oil was investigated by disc diffusion method against three Gram positive (Staphylococcus aureus, Bacillus ceruse, Streptococcus faecium) and four Gram negative (Escherichia coli, Salmonella typhi, Shigella dysenteria, Pseudomonas aeruginosa) bacteria and a yeast (Sacharomyces cervisiae) in comparable with the standard antibiotics. The essential oil of P. roseum showed inhibitory activity against all the bacteria and yeast tested to varying degree. B. cereus and S. faecium were found as the most sensitive and resistant bacteria, respectively. According to these results, it can be concluded that the essential oil of P. roseum has suitable spectrum antimicrobial activity and can be used as natural preservatives in food industry.

Date juice was treated by cross- flow ultra-filtration with molecular weight cut-off (MWCO) of 5 kDa. Optimized levels of feed brix, TMP and operation time were determined as 47.13, 82.11 psi and 30 min, respectively. Under such conditions, 80.94% decolourisation and 97.78% turbidity reduction were obtained while loss of glucose and fructose were estimated to be only 3.49% and 9.62%, respectively. Regarding sweetness, the results of beverage sensory indicated that samples prepared by 100% decolorized date juice, 50% sugar, + 50% stevioside, 50% decolorized date juice and + 50% stevioside did not show significant differences compared with the sample prepared by 100% sugar. From the view point of the bitter aftertaste, samples prepared by 100% sugar and 100% stevioside had the highest and lowest desirability, respectively, while there was no significant difference between colour and clarity of the samples.

Zhumeria majdae is a rare an endemic medicinal plantspecies grown wild in Iran. The hydro distilled essential aerial part oil of Z. majdae analysed by GC–MS. Thirty-one compounds representing 95.36% of the aerial part oil, respectively, were identified, of which linalool (48.14%), camphor (20.71%), limonene (4.83%), trans-linalool oxide (2.69%), 3-Octanone (2.34%), terpinene-4-ol (2.30%), camphene (1.88%), caryophyllene oxide (1.34%), geraniol (1.23%), α-pinene (1.22%), p-Cymene (1.08%) were the major compounds. Total phenolic content was 42.74 mg GAE/g dw and the IC50 in the radical scavenging assay was 32.08 mg/ml. The hydro distilled essential aerial part oil display potential of antibacterial activity against the tested 8 phytopathogenic bacterial such as Bacillus cereus, Bacillus thuringiensis, Enterococcus faecalis, Staphylococcus epidermidis, Salmonella typhimurium, Campylobacter jejuni, Klebsiella pneumoniae and Pseudomonas fluorescens. The inhibition zones and MIC values for all test strains, which were sensitive to the essential oil of Z. majdae were in the range of 33-30 mm and 0.93 mg/ml, respectively. The results support the traditional usage and also possible use of Z. majdae essential oil and extracts in the food, pharmaceutical and cosmetic industries.

This study evaluated the ability of fennel extract to improve the quality of refrigerated minced silver carp over a period of 16 days. Minced silver carp were treated with fennel extract (0.5, 1 and 1.5% w/w), and beta-hydroxy toluene (BHT 200 ppm). The control and the treated fish samples were analyzed periodically (every 4 days) by chemical analysis (Peroxide value (PV), thiobarbituric acid (TBA) and free fatty acid (FFA). Results showed that the fennel extract and BHT could reduce lipid oxidation in the samples compared to the control.  Moreover, minced silver carp treated with 1.5% fennel extract showed the lowest amount of lipid oxidation. The results indicated that fennel extract was improving the quality characteristics of treated fresh minced fish.

Microwave assisted extraction (MAE) tech-nique was employed for the extraction of pectin from black mulberry (Morus nigra L.) pomace in this research. The effects of process variables namely microwave power (300-900 watt), irradiation time (10-30 min) and liquid to solid ratio (15-30 mL/g) on the yield, degree of esterification (DE) and galacturonic acid content (GalA) of pectin were investigated and optimized by using response surface methodology (RSM) with a face canter central composite design. Depending on the extraction conditions, the yield, DE and GalA of pectins varied in the range of 8.87-14.47% (dry weight basis), 44.44-57.06%, and 29.17-43.13%, respectively. The results showed that both the microwave power and irradiation time had highly significant effects on the pectin yield, while the effect of liquid to solid ratio was found to be not significant, in this regard. The optimal extraction conditions for maximum yield, DE and GalA of pectin were power of 900 watt, irradiation time of 18.17 min and liquid to solid ratio of 15 mL/g. Under these conditions, 13.16% of pectin with DE of 55.07% and GalA of 36.94% was extracted. The intrinsic viscosity and viscosity average molecular weight of a representative pectin sample was also determined and it was found to be 1.22 dL/g and 32.78 kDa, respectively. The black mulberry pomace pectin showed a viscoelastic behavior in the frequency sweep test and the crossover between G' and G" occurred at low frequency region (~ 0.07 rad/s).

Sugarcane bagasse contains cellulose, lignin and hemicellulose, 39-42%, 20-25% and 25-27% respectively. So it is can be used as a sugar source in many processes. Lignin and hemicellulose must be removed before hydrolysis of cellulose. Several different pretreatment approaches have been studied. The purpose of this research is comparison of acid, ozone and combination of ozone-acid as pretreatment methods for improving enzymatic digestibility of sugar cane bagasse in pilot plant scale. Sugar cane Bagasse was washed and pretreated by sulfuric acid (BA) 0.1 %, sodium hydroxide (BSH) 0.1% and (BS) steam was done at pressure 2 bar. Sugar cane bagasse was also treated by sulfuric acid (1, 2, 2.5, and 5%) at 121 ºC and 151 ºC. Ozone and ozone-acid methods also was used for delignification of bagasse. Particle diameter of bagasse in all pretreatment methods was 3-4 mm. All pretreated bagasse was hydrolyzed by cellulose enzyme complex and beta-gluocosidase at pH 5 and temperature 45 ºC. Glucose and xylose content of hydrolyzed sample was analyzed by high performance liquid chromatography (HPLC). Acid is the best media for pretreatment of bagasse in comparison with steam and base. The data showed that high concentration of acid had indirect effect on yield of sugar production in hydrolysis step. Furthermore ozonolysis pretreatment of bagasse led to higher amount of glucose in comparison with acid and acid-ozone methods. Moisture content and duration of ozonation had significant effect on sugar content of hydrolyzed solution and sugar content of hydrolyzed samples was 6%.

3-monochoropropane-1, 2-diol (3-MCPD) and 2-monochloropropane-1,3-diol (2-MCPD) and glycidol esters (GE) have been known as food contaminants. These compounds are formed during high-temperature process of different food products such as coffee, edible oils, infant formula, potato based products, bakery products, malt, cooked meats, soy sauces and pickles. In vegetable oils, these compounds are formed during refining, particularly during deodorization step. The studies on MCPD content and their formation routes in vegetable oil are a new area of research. Carcinogenic characteristics of these ingredients are a general concern. Thermal processing such as deodorization and deep-frying can trigger the formation of unpleasant substance such as trans fatty acids cyclic fatty acid esters, or acylglycerol polymers. Refining of edible oils, although eliminates contaminants from the oil, but it leads to the formation of unwanted compounds such as glycidol, glycidol esters, MCPD and MCPD esters. This review gives valuable information of present knowledge on analytical aspect, formation mechanisms of 3-MCPD and GE in vegetable oils and their health implications such as toxicity, carcinogenicity and mutagenicity.