فصلنامه علوم تغذیه و صنایع غذایی ایران
سال چهاردهم شماره 4 (پیاپی 57، زمستان 1398)

Exercise is a good stimulating factor for decrease of blood lipid. Lemon (Citrus limon L.) essential oil with antioxidant properties can prevent oxidative stresses. The present study was carried out to assess effects of four-week consumption of lemon essential oil with swimming training on lipid profile and lipid peroxidation.

Totally, 40 male mice (40 gr ±5) were divided randomly into four major groups (n = 10), including control, swimming, lemon essential oil and swimming with lemon essential oil groups. Swimming practice included four weeks of swimming in 25–27 ºC water for 30 min in each session, five sessions in a week. Lemon essential oil (50 mg/kg) was administered using gavage. Lipid peroxidation and lipid profile were assessed by blood sampling from the animal heart.

Lemon essential oil significantly decreased triglycerides (p < 0.001), LDL-C (p < 0.01), VLDL-C (p < 0.01), cholesterol (p < 0.01) and MDA (p < 0.001). Swimming training significantly decreased triglycerides, LDL-C, VLDL-C and MDA; however, cholesterol and HDL-C did not change significantly. Lemon essential oil consumption with swimming training significantly decreased triglycerides (p < 0.001), LDL-C (p < 0.01), VLDL-C (p < 0.01) and MDA (p < 0.001) and increased HDL-C (p < 0.05).

In general, lime essential oil consumption with swimming training include decreasing effects on lipid peroxidation and lipid profile.

Dietary habits and nutritional behaviors of people are the food culture of every society. The aim of this study was to investigate factors, which affected food diversity in urban households of Iran.

The study was carried out in a cross-sectional and analytical form on 18,627 households. Data were extracted from the Bulletin of Urban Household Expenditure and Income in 2016 published by Iran Statistical Center. Berry Index was used to measure food diversity. The index included scores of zero to one and a greater score indicated a greater food diversification. The study model variables included personal (age, education, gender), social (literacy, geographical region, participation rate) and economic (income, cost) variables.

Increase of every literature person in household percentiles of 10, 25, 50, 75 and 90 increased food diversity by 0.0001, 0.0003, 0.0001, 0.0008 and 0.0007, respectively (p < 0.01). The household per capita expenditure in all percentiles included a significant positive relationship with the food diversity. In median (t = 50%), a 1000-Rial increase in per capita food expenditure resulted in a 2.5-unit growth in food diversity (p < 0.01). Households who lived in south and desert regions included the highest (0.86) and the lowest (0.84) diversities in food regimes, respectively.

Food diversity behaviors in Iranian households mostly depend on their residence. Growth of household income in lower percentiles increases food diversification. Therefore, economic growth can lead to diversification of foods and hence prevention of non-communicable diseases.

Adolescence is the period of rapid growth, alterations in body composition and psychosocial development. Adolescents, who eat well and participate in daily physical activities, live a healthy life. A healthy lifestyle promotes optimal growth and better performance at school and work and minimizes the risk of nutrient-linked chronic diseases. The purpose of this study was to determine dietary diversity, and its relation to anxiety among adolescent high school girls.

This study was a cross-sectional study, which was designed based on the update of HEI-2015. The study population included 412 high schoolgirls aged 11–17. Data of diet, sociodemographic and anthropometric characteristics were collected. Dietary diversity score (DDS) and anthropometric characteristics of the girls were measured. Furthermore, DASS-42 questionnaire was used to report the adolescents who suffered from anxiety. Relationships between DDS and anxiety were assessed.

This study showed that DDS included an inverse correlation with anxiety in adolescents. In students who were healthy, DDS was greater than that in participants with anxiety (p < 0.0001).

Dietary diversity could be inversely associated with anxiety in adolescence. So that by increasing dietary diversity score, the degree of anxiety was lower. Further prospective investigations are needed to confirm this finding.

Drinking dessert is a dairy product with high viscosity and great mouth-feel. Use of fresh lactic cheese whey in formulation of this beverage is one of the recent innovations in dessert production. Due to increasing demands for novel probiotic products, preparation of synbiotic drinking desserts with two various species of Lactobacillus can help to increase diversity and health effects of the probiotic products.

After preparation of drinking desserts, synbiotic drinks were prepared in fermented and nonfermented types using an equal ratio of Lactobacillus rhamnosus GG and Lactobacillus paracasei. Changes in pH, acidity, viability of probiotic bacteria and antioxidant activity of the two samples during storage were assessed and results were compared with each other. Furthermore, the sensory analysis revealed that which type of the drinks was more acceptable.

The pH of both samples decreased during refrigerated storage, while it was more severe in fermented samples. Population of the probiotic bacteria did not change significantly at the end of the storage time. Results showed increases in antioxidant activity during fermentation; however, nonfermented desserts generally included a greater antioxidant activity due to the presence of cocoa powder. The overall acceptance of the nonfermented desserts was more than that of fermented desserts.

Drinking desserts are great carriers for delivering probiotic bacteria to the body. Production of synbiotic drinking desserts is possibly using a mixture of two probiotic bacteria, including Lactobacillus rhamnosus GG and Lactobacillus paracasei. Due to the general acceptance and high antioxidant properties of the nonfermented desserts in comparison with fermented ones, it is recommended to produce this synbiotic drinking dessert in nonfermented type.

Freezing under statically electric fields is one of the novel freezing methods to improve the quality of frozen products by controlling the nucleation process. The objective of this study was to investigate effects of freezing under electrostatic fields on the freezing parameters and microstructures of frozen button mushrooms.

Mushroom samples were frozen at -30 °C under electrostatic fields with voltages of 0.0, 4.5, 9.0 and 13.5 kV. Temperature of the sample center was recorded during freezing. Furthermore, microstructure of the mushrooms was analyzed using light microscopy.

Assessment of the freezing parameters has shown that use of electric fields during freezing increases the nucleation temperature and phase transition time. Increased electric field voltage up to 4.5 or 9.0 kV increased the nucleation temperature, while the nucleation temperature decreased again with further increases in voltage. Furthermore, use of electric field decreased damages to mushroom microstructures during freezing and the smallest ice crystals were formed at voltages of 4.5 and 9.0 kV.

In conclusion, freezing under electric field increases the nucleation temperature and decreases the ice crystal size; therefore, improves the microstructure of button mushrooms. Voltage increase has shown an optimum value for the increase of nucleation temperature and preserve of mushroom microstructure.

Aflatoxin is one of the most important and common toxins in high consumption foods such as rice, which can threaten health of the consumers. In this study, risk of total aflatoxin based on its exposure levels and adverse effects was assessed in Iranian rice.

This study was carried out on total aflatoxin in 60 national rice samples collected based on the Food Safety and Nutrition regions. The risk score was assessed in each region and through the country using quantitative risk assessment method based on the estimated exposure, provisional maximum tolerable daily intake (PMTDI), carcinogenic slip factor (CSF) in the two groups of HBAg+ and HBAg- and effects of various cooking methods.

The mean and standard deviation of the total aflatoxin content in rice samples included 1.13 and 1.8 μg/kg, respectively. Results of the exposure assessment in terms of minimum, average and maximum concentrations of the contaminants and the consumption volume in each region for the two groups of HBAg+ and HBAg- showed that the highest risk score was linked to rice cooking method in rural areas of relatively unsafe regions and in HBAg+ group.

Despite a high-risk score volume of the rice consumption in Iran, results have shown that the total aflatoxin in rice is lower than the maximum eligible limit by the Iranian National Standard (30 μg/kg); therefore, total aflatoxin contamination of the rice in Iran includes no risks to the health of consumers.

Bioprotective starters, especially lactic acid bacteria, are used in fermentation and biological preservation of the meat products and considered as appropriate substitutes for the chemical preservatives. The aim of this study was to use Lactobacillus plantarum and Pediococcus acidilactici as bioprotective cultures and probiotics for the growth control of important foodborne pathogens and increase of the poultry meat shelf life.

Starter culture of 8.5 × 107 CFU/g, pathogenic bacteria of 105 CFU/g, citric acid concentration of 1% and lactose concentration of 7% were inoculated in chicken breasts. All treatments were stored at 25 °C for 24 h followed by 4°C ±1 for 72 h. Changes in population of the starter cultures, decreases in pathogenic bacteria and changes in pH values were assessed within a period of 72 h.

Results showed that the population of lactic acid bacteria increased in pathogen-containing treatments. Lactobacillus plantarum and Pediococcus acidilactici cultures respectively decreased Listeria monocytogenes and Salmonella typhimurium populations by 1.6 and 1.5 log folds until the Day 3 of fermentation, compared to control samples. Pediococcus acidilactici treatment included the strongest effects on decreasing populations of the pathogenic bacteria (p < 0.05). During fermentation and storage, a constant pH decrease was observed in inoculated samples with lactic acid culture, compared to control samples.

Use of bioprotective starters can play a significant role in safety of meat products and increase of their shelf-life as well as creating desired properties in meats.

Essential and minor components of the goat milk are unique ingredients in production of various food products. In this study, characteristics of Nodooshan goat milk were investigated and volatile compounds were identified in traditional Nodooshan goat cheese during ripening.

Physicochemical tests were carried out on raw milk, fresh cheese and ripened cheese in brine. Moreover, lipolysis and analysis of the fatty acid composition and volatile compounds of the various cheese samples were carried out using GC-MS.

Results of the physicochemical tests on fresh raw milk, fresh cheese and ripened cheeses in brine (1 and 2 months) showed that sample appearance, color, smell and taste were according to National Iranian Standards ripened cheese samples were rich in fat, protein, moisture and salt. Analysis of the fatty acid composition demonstrated that the predominant saturated fatty acid content in all samples was palmitic acid (C16:0) and the dominant unsaturated fatty acid in all samples was oleic acid (C18:1). Furthermore, the major volatile components in fresh and ripened cheeses in brine were detected using GC/MS.

Based on results from this study, fatty acid profile of the cheese changes during the ripening. Moreover, variety of the volatile compounds in ripening increases but the number of these compounds decreases.

Falafel is a cheap fast food with increasing consumptions. Since falafel is fried at high temperatures at the presence of oxygen and absorbs a large quantity of oil, its routine consumption is a potential risk to human health. Due to the increasing public demands for low-oil foods, the aim of this study was to investigate effects of Arabic, guar and xanthan gums as edible hydrocolloids on qualitative characteristics of fried falafels.

Hydrocolloids were added to the falafel formula at three levels (0.5, 1 and 2%); then, moisture content, oil uptake, texture hardness, color properties (L* a* b* indices), sensory attributes and adsorbed oil fatty acid profile were assessed.

Addition of hydrocolloids significantly increased moisture contents of the fried falafels. Quantity of the oil uptake and hardness of the samples significantly decreased by the addition of hydrocolloids since adding 2% of Arabic gum decreased the oil uptake of falafel by about 40%. Furthermore, addition of hydrocolloids decreased brightness (L*) and increased redness (a*) and yellowness (b*) of the samples. Sensory evaluation results showed that addition of hydrocolloids increased the appearance color, crispness and overall acceptability of the falafel samples, while mildly decreased the intensity of taste. Fatty acid profile of the absorbed oil by fried falafels was not significantly affected by the addition of hydrocolloids; however only quantity of unsaturated fatty acids increased.

Addition of natural hydrocolloids to falafels can greatly decrease oil uptake with no significant changes in organoleptic properties, which is important for the health of consumers.

Antioxidants are used to decrease oxidation of oils and increase shelf life of foods for centuries. Nowadays, researchers investigate for the replacement of synthetic antioxidants with antioxidants from natural sources. The purpose of this study was to investigate effects of quinoa enzyme-hydrolyzed proteins on functional and antioxidant properties of the produced peptides.

In this study, proteins of the quinoa seeds were extracted and hydrolyzed with alcalase and pancreatin enzymes. The hydrolyzed proteins were assessed for the degrees of hydrolysis, solubility, emulsifying capacity, foaming capacity and antioxidant properties. Furthermore, DPPH free radical scavenging activity, hydroxyl radical scavenging activity, reducing power, ABTS radical scavenging activity, Trolox equivalent antioxidant capacity (TEAC) and iron and copper ion chelating activity were used to assess the antioxidant properties.

Results showed that the enzymatic hydrolysis significantly increased solubility, foaming capacity and emulsifying capacity, especially at isoelectric point and acidic pH. Free radical scavenging of DPPH (from 16.85 to 56.04%), hydroxyl radical scavenging (from 26.31 to 63.91%), reducing power (from 0.44 to 0.95 absorbance at 765 nm), ABTS radical scavenging (from 30.01 to 68.42%), Trolox equivalent antioxidant capacity (from 0.73 to 1.83 mM), iron ion chelating activity (from 36.91 to 70.64%), and copper ion chelating activity (from 3.76 to 10.76%) increased to the highest levels after enzyme hydrolysis.

Results of this study have shown that enzymatic hydrolysis can improve functional properties of the quinoa seed proteins. Antioxidant capacity of the hydrolyzed proteins is significantly higher than non-hydrolyzed proteins. Improvement of the functional properties and antioxidant capacity of the hydrolyzed proteins depend on hydrolysis time and enzyme type.

In recent years, edible films and coatings that are nutritious and able to significantly control microbial loads for the food safety have been further popular. In this study, effects of nanoclay film of citrus essential oil on bacterial pathogens of Listeria monocytogenes, Vibrio parahaemolyticus, Streptococcus iniae and Salmonella typhi were investigated in fishery products, including silver carp surimi, grass carp sausages and common carp tofu.

The nanoclay film was prepared using solution of sodium alginate and solid sodium gelatin. The film solution was mixed with 0.2, 0.4 and 0.6% of citrus essential oil. Bacterial load in fish products was investigated on Days 0, 7 and 14.

The microbial load significantly increased by 0.2, 0.4 and 0.6% (p < 0.05) in nanoclay treatment of the citrus essential oil in silver surimi, grass carp sausage and common carp tofu from Day 0 to Day 14. Load of bacteria in fishery products included 0.4 and 0.6% in nanoclay treated with citrus essential oil until Day 14, compared to controls. The exceptions included common carp tofu contaminated with Salmonella typhi and Streptococcus iniae and grass carp sausages contaminated with Streptococcus iniae treated with 0.6% citrus essential oil contained nanoclay; in which, the bacterial load increased up to Day 14.

Results showed that nanoclay with 0.4 and 0.6% of citrus essential oil was able to control the microbial load in fisheries products. This activity depended on the bacterial species as well as percentage of the citrus essential oil.

Nowadays, reducing sodium intake is one of the most important goals of global and national programs for decreasing of non-communicable diseases such as hypertension and cardiovascular disease and salt is the most important source of sodium intake in the diet. Bread has remained one of the staple food in many cultures and societies in different parts of the world. Despite key roles of breads in Iranian food consumption patterns, a little information is available on salt (sodium chloride) intake in traditional and industrial breads. The aim of the current study was to determine the salt content in traditional, volume and semi-volume breads in Tehran, Iran in 2016.

In this study, 151 samples including traditional and industrial breads were collected randomly from various bakeries and markets of Tehran. Salt content (sodium chloride) in traditional (Sangak, Barbari, Taftoun and Lavash) and industrial (Volume and semi-volume) breads was investigated according to Volhard method of National Standard.

The mean salt in traditional breads of sangak, barbari, taftoun and lavash included 0.41±0.37, 1.43±0.40, 1.07±0.31 and 1.14±0.45 gr/100 g, respectively. This value for volume and semi-volume breads included 1.39 g/100 ±0.58. Nearly 93 %, 21%, 38 % and 43% of the salt content of Sangak, Barbari, Lavash and Taftoon respectively included in the national salt limit were found to be compliant.

Considering the per capita intake of different types of bread in Tehran, the salt intake of Sangak, Lavash, Berberi, Taftoon and Volume and semi-volume breads were 0.13, 0.54, 0.56, 0.36 and 0.12 g/day respectively.
Keywords: Salt, Sodium chloride, Bread, Iran, Dietary intake