فصلنامه علوم تغذیه و صنایع غذایی ایران
سال چهاردهم شماره 3 (پیاپی 56، پاییز 1398)

Citrulline (cit.) is a non-essential amino acid derived from watermelon, which affects improving glucose tolerance and lipid and energy metabolisms. The aim of this study was to investigate effects of citrulline supplementation on non-alcoholic fatty liver.

In this randomized clinical trial, 50 patients with NAFLD were randomly assigned to receive either cit. or placebo. Patients received four capsules of 500 mg (cit. or placebo) daily. Both groups were advised to follow energy-balanced diets and physical activities. Liver enzymes and hepatic steatosis and fibrosis were assessed at the baseline and end of the study. Paired t-test, t-test and chi-2 were used for data analysis.

No significant differences were observed for the monitored variables between the two groups at the baseline. After treatment, the experimental group consuming cit. supplementation showed a statistically significant decrease for ALT and hepatic steatosis, compared to control group (P<0.05). Furthermore, serum levels of AST and GGT and also hepatic fibrosis showed no significant differences between the two groups (P≥0.05).

Results of this study showed that citrulline could decrease ALT and degrees of steatosis in cit. group with no significant differences between the two groups. In cit. group, liver enzymes of alanine aminotransferase  decreased (7.26 IU/L), compared to control group (7.19 IU/L). Moreover, citrulline demonstrated no significant effects on hepatic fibrosis and other liver enzymes. To investigated effects of citrulline on liver, further studies with various doses and periods of time are necessary.

Oxidative stress has been reported to provide neurodegeneration in multiple sclerosis (MS). Coenzyme Q10 is an endogenous lipid-soluble antioxidant. Up-to-date, no intervention studies have investigated coenzyme Q10 supplementation in MS. The purpose of this study was to investigate oxidative stress and antioxidant enzyme and lipid peroxide activities in women with MS following administration of coenzyme Q10 (300 mg/day).

This study was designed as a single-blinded, randomized, parallel placebo-controlled study. Women with MS (n=30) were randomly assigned to placebo (n=15) or coenzyme Q10 (300 mg/day) (n=15) group. The intervention was completed within eight weeks. Plasma coenzyme Q10, oxidative stress (MDA) and antioxidant enzymes activity (SOD, GPX, TAC) were assessed. Data were analyzed using two independent-samples tests (Mann-Whitney U) (P<0.05).

The antioxidant enzyme activity (SOD) (P = 0.001) and coenzyme Q10 (P = 0.002) significantly increased. However, no significant differences were reported for serum levels of MDA, GPX and TAC between the two groups (P > 0.05) after eight weeks of coenzyme Q10 supplementation.

In conclusion, this study has demonstrated that a dose of 300 mg/d of coenzyme Q10 can improve antioxidant enzyme system with no effects on peroxidation lipid (MDA) and DESS in women with MS.

Food insecurity can result in undesirable health outcomes in various groups. Since pregnant women are of vulnerable groups within the society and their food insecurity may cause complications during pregnancy, the aim of this study was to investigate food security status and other factors linked to general health in pregnant women referred to health care centers in Khorramabad City, Lorestan, Iran.

This study was carried out on 148 pregnant women selected by random cluster sampling from eight comprehensive health centers in Khorramabad. Food security was assessed using Radimer-Cornell questionnaire. Furthermore, general health questionnaires (GHQ) with 28 questions and nutrition evaluation forms were completed for each subject by health center nutritionists through interviews. For data analysis, statistical tests such as student T test and chi square were used to identify the associated factors of logistic regression.

Results demonstrated that the food security of pregnant women was significantly correlated with education level, number of previous pregnancies, pre-pregnancy body mass index (BMI) and weight gain range based on pre-pregnancy BMI (P<0.05). Moreover, a significant negative relationship was seen between the food insecurity of pregnant women and their general health scores in all four subscales (P<0.05). No significant relationships were seen between the age and history of abortion in pregnant women with food security.

Women in food insecurity households are more likely to show lower general health scores and have fewer children and lower education level. These can endanger food-insecure women at higher risks.

Various types of exercise cause damages at cellular levels in muscles. Muscle damages caused by exercise increase levels of C-reactive protein (CRP) in blood. The aim of this study was to assess effects of resistance training and ta-hydroxy beta-methylbutyric acid (HMB) supplementation on responses of high sensitivity C-reactive protein (hs-CRP) and lipid profiles to strenuous activity in adult male rats.

In total, 32 healthy rat were randomly divided into four major groups of training, supplement, training-supplement and control groups. The experimental group carried out eccentric resistance for two weeks, five days a week. Supplementary groups received supplemental HMB daily for up to 450 mg/kg body weight per day using gavage. In general, one session of strenuous eccentric resistance activity (stepping down from ladder with a gradient of 80% by closing 120% 1RM at the back of the rat tails) was carried out 24 h before and after the intervention (supplementary and training). Data analysis was carried out using ANOVA and Tukey post hoc test at P ≤ 0.05.

Results showed that HMB supplementation and eccentric resistance training alone included no effects on hs-CRP, cholesterol, triglycerides, LDL-C and HDL-C in adult male rats after strenuous activity (P < 0.05). However, combination of HMB supplementation and eccentric resistance training included a significant effect on these variables after a strenuous activity in adult male rats (P= 0.001).

Based on the results, combination of supplemental HMB and eccentric resistance training may help improve inflammatory statuses and lipid profiles.

In this study, hydrolysis condition optimization of the pumpkin (Cucurbita pepo) seed proteins was carried out achieve maximum DPPH radical scavenging and nitric-oxide inhibition properties using Design Expert Software and response surface methodology.

In general, 1–3% concentrations of pepsin enzyme, 30–40 °C temperature and 120–100 min time were selected as the independent variables.

Results showed that the optimum conditions for achieving maximum DPPH radical scavenging and nitric-oxide inhibition activities included temperature of 32 °C, time of 161.5 min and an enzyme-substrate ratio of 3% with antioxidant and nitric-oxide inhibitory activities of 54.63 and 89.09%, respectively. These results were largely similar to the results suggested by the software (56.03 and 91.92%, respectively).

Based on the results, hydrolyzed proteins of the pumpkin seeds include good antioxidant and nitric-oxide inhibitory activities and can therefore be used as natural compounds for replacing synthetic preservatives in food products.

Cucumber includes a short postharvest life and loses its quality fast. Novel technologies such as coating and modified atmosphere packaging are promising methods in preserving fresh products. Therefore, the aim of this study was to use a combination of chitosan coating and modified atmosphere packaging to preserve quality attributes of the cucumber Royal var. and to estimate the vegetable shelf-life.

In this study, cucumber (Royal var.) was coated using chitosan and packed under three various atmospheres of A) air; B) active MAP (10% of O2 and 5% of CO2); and C) passive MAP (21% of O2 and 0.1% of CO2). Texture firmness, total soluble solid, chlorophyll content and organoleptic properties of the cucumbers were determined at 5-day intervals during 15 days of storage at 4, 10 and 20 °C. Shelf-life of the cucumbers was modeled under various treatments.

Variance analysis showed a significant effect (P<0.05) of four factors (coating, gas concentration, temperature and time) on postharvest properties of the cucumbers. The most change in TSS was observed in Package A cucumbers stored at 20 °C. These also showed the most weight loss. At 4 and 10 °C, firmness was well preserved in Package B; in which, the coated cucumbers included the least firmness loss compared to uncoated ones. Combination of chitosan coating and modified atmosphere packaging positively affected quality parameters of the cucumbers Royal var. Relatively, effects of active MAP were significant at 10 °C. The maximum shelf life was seen for the coated samples stored in active MAP at 4 °C (17 days) following by 10 °C (15 days).

Based on the current results, combination of chitosan coating and active MAP can be suggested for the packaging of cucumbers (Royal var.).

Food industries are searching newer and cheaper ways to safely produce and storage foods. Nanotechnology offers several options for the production, encapsulation and emulsion of foods. The aim of this study was to investigate effects of nanoemulsion of Zataria multiflora essential oil on microbial, chemical and sensory properties of silver carp fillets.

In general, effects of four treatments of 1) fillet without nanoemulsion of Z. multiflora essential oil (control), treatment; 2) 0.5% nanoemulsion of Z. multiflora essential oil, treatment; 3) 1% nanoemulsion of Z. multiflora essential oil and treatment; and 4) 1/5% nanoemulsion of Z. multiflora essential oil on microbial and chemical parameters of silver carp fillets were investigated trice on Days 0, 3, 6, 9, 12 and 15 at refrigerator temperature.

With increasing Z. multiflora essential oil nanoemulsion, the chemical indices (pH, TVB-N, TBA, PV and FFA) decreased. Microbial count in all treatments, except for 1.5% Z. multiflora essential oil nanoemulsion, crossed the eligible limit (107 Log cfu/g) on Day 15. For sensory evaluation 1.5 and 1% of treatments of Z. multiflora essential oil nanoemulsion included higher qualities. In all four treatments, the color index included bright brown. Results have shown that Z. multiflora essential oil nanoemulsion acts as a natural preservative and increases biochemical parameters (pH, TBA, TVB-N, PV and FFA) while preserving qualitative characteristics of the fillets. Furthermore results demonstrated that the bacterial growth rate was slowed down.

Treatment of 1.5% Z. multiflora essential oil nanoemulsion included the highest efficiency and increased shelf life of the silver carp fillets by 12 (4 days longer than the control).

Mayonnaise is an oil-in-water emulsion stabilized by emulsifying property of the egg yolk. The purpose of this study was to use hazelnut meal milk as an egg-yolk (highly rich in cholesterol) substitute and to find the optimal formula for producing mayonnaise.

: Samples of mayonnaise with decreased egg yolk contents were produced using hazelnut meal milk at five levels (0, 25, 50, 75 and 100%) and xanthan-guar gum at five levels (0, 0.05, 0.10, 0.15 and 0.2%) using central composite design response surface method. Then, hardness, adhesive force, adhesiveness, heat and physical stability of the samples were evaluated and modeling was carried out.

The high coefficient of determination within the models showed the ability of most models to predict data and match responses with real analyzes. Samples with 50% of meal milk (0.16% of gum) and samples with 87% of meal milk (0.11% of gum) were demonstrated as optimal samples. For verifying the prediction, a validation test was carried out. Results showed that samples conformed to the predicted samples in terms of hardness, adhesive force, adhesiveness, physical stability and heat stability and only non-significant differences were seen (P>0.05).

It can be concluded that mayonnaise with low-cholesterol levels and similar properties to the controls can be produced using these two optimal formulas.

Stability of the products made from pistachios depends on stability of the oil. Oxidized oil includes unpleasant taste and thus its quality and shelf-life decreases. The aim of this study was to assess pistachio oil oxidation stability alone and in combination with Carotino oil and monoglyceride emulsifier using method of accelerated temperature (60 °C).

Qualitative factors (including free fatty acids, peroxide value, anisidine value, TOTOX value, 2,4-decadienal, color and sensory analysis) of the stored samples were evaluated on Days 0, 5, 10, 15, 20 and 25.

In all treatments, including pure pistachio oil, pistachio oil with Carotino and pistachio oil with Carotino and monoglyceride emulsifier, free fatty acids, peroxide value, anisidine value, Totox value, 2,4-decadienal and a-value increased during storage with the highest increase seen on Day 25. In contrast, L* and b* values and fresh odor decreased during storage with the lowest value observed on Day 25 of storage. On Day 25 of storage, free fatty acids, peroxide value, anisidine value, TOTOX value and 2,4-decadienal were higher in pure pistachio oil than pistachio oil containing Carotino alone and pistachio oil containing Carotino and emulsifier. The 2,4-decadienal was not detected in samples on Day 0 but on Day 25 with a higher quantity in pure pistachio oil than other oils. This was not significantly different between pistachio oil containing Carotino and pistachio oil containing Carotino and emulsifier.

Addition of Carotino and emulsifier either alone or in combination to pistachio oil affected the oil stability. Based on the TOTOX value, this addition increased the oil oxidative stability from 15 to 20 days at 60 °C. High quantities of oleic acid and palmitic acid in Carotino and stabilizing effects of emulsifier resulted in a higher stability for a combination of pistachio oil, Carotino and emulsifier, compared to other oils.

Changes in lifestyles and consequently food patterns and consumption of ready to eat and fried foods have increased probability of Chronic non-communicable diseases (NCDs) occurrence, and many studies have illustrated relation between -survived salt, total fat, saturated fatty acids, and trans fatty acids contents of industrial and guilt fried products in Iran.

 In this survey, 69 samples including 18 samples of industrial fried products (potato chips, shoestring Potato, fried onion, and fried garlic) and 51 guild fried products (potato chips,  string potatoes, fried onion, and fried garlic) were prepared from different parts of country. According to case, the amount of salt, total fat, saturated fatty acids, and trans fatty acids was determined, and their conformities with national standards investigated.

 The mean of total fat for industrial and guilt potato chips was 42% w/w, and measured for strip potato, shoestring potato, industrial and guilt fried onion 17, 34, and 47% w/w, respectively. Among 69 samples, only 5.47% did not have conformity with national standard about total saturated fatty acids in oily phase. The total trans fatty acids in oily phase of all samples was matched within maximum level which has specified for industrial and guild frying oil in national standard.
 

Due to the high level of fat content in all type of potato chips and fried onion, it can be suggested to use reducing oil absorption methods, and revise relevant national standards. The other notable point is the highest specified maximum level of total saturated fatty acids for industrial and guild frying oil (maximum 45% w/w).

Because of the increasing demands for functional foodstuffs, use of dietary fibers in production of snacks is further considered. The aim of this study was optimization of date kernel powder proportion to improve the physicochemical properties of extruded snacks.

Two screw extruders were used to formulate and prepare snacks. In this study, effects of  date kernel powder on physicochemical properties of the extruded samples were investigated. The physicochemical properties included moisture content, water absorption index (WAI), water solubility index (WSI), oil absorption index (OAI), texture, color, total phenol, antioxidant activity and SEM during 90 days of storage.

Incorporation of date kernel powder decreased moisture content, L*and b* values and water absorption within the samples. Furthermore, date kernel powder increased the overall acceptability, a* value OAI and antioxidant activity of the samples. Date kernel powder increased total phenolic compounds up to 5.85 (Gallic acid equivalent) in the optimized samples, compared to control samples (4.44 Gallic acid equivalent). Moreover, the powder increased hardness and denser texture formation in the optimized samples.

Based on the current results, high nutritional values and functional properties of the extruded snacks can be improved by incorporation of date kernel powder to foods.

Gamma irradiation has been shown as an effective technology to decrease or eliminate microbial contamination in raw and cooked meat products. However, irradiation-induced physicochemical changes are important to accept the technology by meat industries and consumers. The objective of this study was to assess effects of gamma irradiation (0, 2, 4, 6 and 8 kGy) on nitrite residue, lipid oxidation, total volatile nitrogen and color in two heated meat products (sausages) during refrigerated storage at 4 ºC for 28 days.

Two groups of emulsion meat products with various proportions of meat (40 and 65%) were irradiated at 2, 4, 6 and 8 kGy doses. Residual nitrite and TVN tests were carried out on Weeks 0, 7, 14, 21 and 28. The color test was carried out using the Hunter Lab system on Weeks 0 and 4 of storage.

Radiation at 8 kGy doses resulted in a significant decrease in nitrite in both groups (P < 0.05). The TVN value in radiated samples was significantly lower than that in non-irradiated samples (controls). Furthermore, high-dose radiation (doses of 6 and 8 kGy) in the two food products significantly decreased the red index (a-value) and significantly increased the TBA value (P <0.05).

Based on the results from chemical properties of the radiated products, irradiation is suggested at 2 and 4 kGy doses as appropriate doses.