Journal of Food Biosciences and Technology
Year:2019 | Volume:9 | Issue:1|Papers Count:10

Phthalates are esters of phthalic acid, mainly used as plasticizer in polymeric packaging materials. The main objective of this research was to determine the exact roots of the phthalate esters in the Iranian flexible/laminated packaging films commercially used for food products such as ketchup, spaghetti, mayonnaise, black tea and snack foods. This investigation was carried out by analyzing the layer by layer constituents of the commercial packaging multi-layer films. Twenty samples have been provided by three different known Iranian companies and analyzed by GC/MS/SIM method. The possibility of film contamination passing through the processing line and the risk of transferring of the phthalate esters from printing inks during winding the printed film (set-off migration) have been also studied. Four different types of phthalate compounds were found in all of the film samples in the range of 1.58-120.99 ppm. No serious phthalate contamination source was distinguished in the film processing line and no set-off migration was observed. The results showed that the total amounts of phthalates in the printed films were higher than the specific migration limit regulatory established for this group of compounds and it may be concluded that the main origin for phthalate esters in the Iranian laminated flexible films are the printing inks.

The possible use of Lactobacillus brevis IBRC-M10790 with degrading phytase activity was investigated in sourdough and Barbari bread –using 20 and 30% of sourdough in the formulation- in order to enhance the nutritional bioavailability, and the efficiency of the bacteria in decreasing phytate via using in sourdough was compared to yeast. Results showed that L. brevis IBRC-M10790 has better efficiency in phytate reduction than yeast alone or the combination of yeast and bacteria, and can be effectively used for improving the nutritional properties of Barbari bread. Use of 30% sourdough in bread formulation gave the highest percentage of phytate reduction in breads. It seems that not only the percentage of sourdough (the amount of used yeast), but also fermentation time is important in reducing the level of phytate in Barbari bread. Statistical analysis revealed that pH is not the major factor for phytate reduction in Barbari breads with different percentages of sourdough.

Since rice is a staple food most consumed world-wide, there have been increasing health concerns regarding exposure to arsenic through rice consumption. Several studies have reported the accumulation of arsenic in rice grains cultivated in regions with elevated levels of arsenic in groundwater or contaminated soil. Therefore the principal aim of this study was determining the amount of arsenic in Iranian rice cultivated in the same farms in two consecutive years and arsenic tracking through agricultural water and soil. Therefore different provinces (Mazandaran, Gilan, Fars, Ghazvin, Lorestan and Khozestan) with high harvested area and various weather conditions were selected. Since the arsenic levels in water and soil that were used for rice cultivation are effective on adsorbed arsenic by the rice, therefore to specify the origin of the contamination, sampling from soil, water and unpolished rice of each selected farms were carried. Total arsenic content was determined from the digests by hydride generation atomic absorption spectrophotometer. The results indicated that accumulation and the increase in arsenic content of agricultural soil causes an increase in the arsenic content of white rice. The results have also shown that arsenic contents in all the investigated white rice samples are less than the maximum limit specified by the national standard (0.15 mg/kg), and no significant difference was observed in the arsenic content in two consecutive years of rice cultivation. Therefore the control of arsenic content in water used for irrigation, limited the usage of chemical fertilizers and pesticides that might affect the concentration of arsenic in the soil and maintain the aerobic conditions during either the vegetative or the reproductive stages of the rice growth that might reduce the concentration of arsenic in the soil and consequently in the rice.

Fat has an important role in creating texture, color and viscosity; but, it might be a source of many diseases in human. Mayonnaise is one of the most widely used sauces that contains fat in its formulation. There is an increase demand in reduction of the amount of fat in the diet or use of unsaturated fat. In the present study, mayonnaise samples containing various amounts of sesame oil were produced. Physical and sensory properties were carried out. Furthermore, the consistency coefficient and flow behavior index were calculated as rheological parameters. All mayonnaise samples fitted by power-low model exhibited non-Newtonian and pseudoplastic behavior. Mayonnaise containing 100% sesame oil showed maximum redness and minimum lightness. The sensory results demonstrated that increasing in the amount of sesame oil led to a reduction in overall acceptability. In conclusion, sesame oil at levels of 20% was recommended to be used in mayonnaise formulation for enhancing the nutritional value of mayonnaise.

Heat and mass transfer phenomena that take place during frying cause physicochemical changes, which affect the colour and surface of the fried products. The effect of frying temperature on the colour changes and heat transfer during deep fat frying of garlic has been investigated. The colour scale parameters redness (a*), yellowness (b*) and lightness (L*), and color change intensity (DE) were used to estimate colour changes during frying as a function of oil temperature and time. L* value of fried garlic decreased during frying but a* and b* values were increased. A first-order kinetic equation was used for each one of the three colour parameters, in which the rate constant is a function of oil temperatures. The results showed that oil temperature have a significant effect on the colour parameters. Different kinetic models were used to fit the experimental data and the results revealed that the power model was the most suitable to describe the color change intensity (DE). Center temperature of garlic slice increased with increase in oil temperature and time during frying.

Salt is a requirement material for human body but should be regulated as its excessive consumption might lead to heart disease and blood pressure. Processed foods due to high salt content might include about three quarter of the daily salt intake therefore many people consume more than their recommended allowances. Processed foods contain added salt for varieties of reasons namely to enhance the taste, develop structure of product and increase microbiological stability by reducing water activity. Methods to reduce salt content are required for consumers that will intake less amount salt while saltiness is not reduced. Therefore salt release from biopolymers is the aim of this research to reduce the amount of salt in processed foods while not changing the saltiness, therefore salt should be trapped in a gel.

The tendency to consume food with lower sugar content and alternatively healthy foods and food products are rising. High levels of sugar in date syrup might be used as a good alternative to sugar in various food products. Iran is one of the main producers of date fruit and it is possible to produce foods with high nutritional values from date to replace high-sugar content food. The formation of acrylamide in date syrups as the result of various procedures of heat treatment and extent of its formation has made the researchers interested in this field of study to investigate the formation of this compound quantitatively by the application of high-pressure liquid chromatography. The results indicated that some of the date syrup samples that were collected in the Iranian market had significant quantities of acrylamide. It is therefore concluded that the date syrups might be considered as a high-risk product due to the formation of acrylamide that is considered a carcinogenic compound.

The migration of packaging material constituents into food is a product of the interaction between the food and packaging material. This phenomenon is of importance because some migrating substances may be toxicologically carcinogenic and endanger the consumer safety. Polystyrenes are used in many food-contact applications for the packaging of aqueous-based, fatty and dry foods. The correlation of residual styrene concentrations in polystyrene with styrene migration into food-simulating solvents is of interest in order to predict the potential exposure of consumers to styrene from food-packaging applications. GC-Mass chromatography was used to determine the migration of styrene monomer into food simulant. Differential simulants (water, 10% ethanol, 3% acetic acid and olive oil) were used to evaluate the effect of heat treatments on styrene migration. It was observed that the migration of styrene is significantly higher in microwave and traditional thermal process than vacuum heating. In additions among different simulants, ethanol had significant higher migration than other simulants. Migration of styrene was increased after 30 minutes heating in all treatments. In addition, the amount of polystyrene migration into the simulants was below the standard limit set by the European Commission for secure PS food packaging.

The effect of different levels of inulin (0, 1.5 and 3 %) and probiotic bacteria including Lactobacillus acidophilus and Lactobacillus casei on chemical properties (pH and titratable acidity) and viable count of probiotic strain of sweet cream during 30 days for 15-day interval at 4oC were studied. All experiments were carried out in three replications. The results showed that during the refrigeration storage of samples, pH decreased and acidity increased significantly. The addition of inulin caused significant changes in pH, acidity and the viability of probiotic strains. By increasing the level of inulin to 3%, the pH of the cream samples decreased, and the acidity and counts of the probiotics increased significantly and this was more significant in Lactobacillus acidophilus, although the treatment containing Lactobacillus acidophilus had the highest acidity. The probiotic survival evaluation also indicated that inulin treatment at 3% level was the best treatment for increasing the viability of the probiotics in cream. The results showed that the addition of prebiotics, such as inulin, could play an important role in increasing the viability of probiotics. In general, changes in the chemical properties of sweet cream during the refrigeration were standard, which could be considered as a synbiotic product and sweet cream as a dairy product can also be considered as a good carrier for probiotic bacteria.

Soyabean might be considered as the most popular oil seed crop in the world and the extracted oil has gained it is popularity due to it is application in formulated food products as well as by itself as oil or hardened form as frying or cooking media. Soyabean oil has been subjected to various refining stages in particular deodorisation where different classes of compounds are collected in the received distillate. A considered quality of sterol and tocopherol fractions are collected in this fraction in the same order as are present in the crude oil. The collected fractions indicated that b–sitosterol among the class of sterols and g and d tocopherols among the class of tocopherols were the predominant compounds present. Therefore two mentioned classes of compounds individually or together might be considered valuable products to be used in the food formulations.