فصلنامه علوم تغذیه و صنایع غذایی ایران
سال هفتم شماره 4 (پیاپی 27، زمستان 1391)

Milk and dairy products are generally recognized as healthful foodstuffs. Their negligible content of polyunsaturated fatty acids (PUFAs) has prompted investigators to consider fortifying them with long chain PUFAs، but the main challenge is the high susceptibility of PUFAs to oxidation and rancidity. Therefore، in the present study the possibility of using long chain PUFAs to fortify Doogh (a traditional Iranian yoghurt-based beverage)، as a functional dairy product، as well as the effect of different factors on the physical stability and peroxide value of the fortified Doogh during storage، were determined. ω-3-Fatty acid-fortified Doogh was prepared using yogurt، water، salt، the soluble phase of gum tragacanth، and crude rapeseed، soy bean، and fish oil. The fortified Dooghs (a mixture of oil and yoghurt or of Doogh and oil) were homogenised using ultrasound at different amplitudes and durations in order to find the optimum processing conditions (amplitudes and duration). Moreover، effects of several factors (heat treatment، storage temperature، intensity and duration of sonication، and oil content) on the physical stability and peroxide value of the fortified Dooghs during storage (35 days) at 2 temperatures (5 and 22˚C) were determined. The findings showed that the preparation method of fortified Doogh had significant effects on its homogenization extent and physical stability. Furthermore، during storage the peroxide value of the samples increased، particularly at the higher temperatures، while they were quite stable physically. It may be concluded that ultrasound treatment can homogenize and stabilize ω-3-fatty acid-fortified Doogh، with no undesirable effect on peroxide value during storage at refrigeration temperatures.

Due to low consumption of leguminous foods across populations، not much information is available on possible independent role of legumes in inflammation. The traditional Iranian diet provides an opportunity to investigate possible association between intake of legumes and health. This study was carried out to determine the association between legume consumption and the serum levels of adhesion molecules and inflammatory biomarkers in Iranian women. In this cross-sectional study، trained dietitians administered a validated semi-quantitative food frequency questionnaire (FFQ) for assessment of usual dietary intakes in a sample of 486 Tehranian female- teachers aged 40-60 years selected by a multistage cluster random sampling method. Legumes in the FFQ included lentils، peas، chickpeas، different kinds of beans (broad beans، etc.)، and chickling vetch. Blood samples were taken to measure the plasma concentrations of adhesion molecules and inflammatory biomarkers. After controlling for potential confounders، including dietary variables، as compared to women with the lowest legume intake، those with the highest legume intake had lower circulating levels of E-selectin (percent difference from bottom quintile (−14. 1%، p-trend=0. 04)، soluble intercellular adhesion molecule-1 (sICAM-1) (−20. 3%، p-trend<0. 01)، and soluble vascular cell adhesion molecule-1 (sVCAM-1) (−15. 6%، p-trend=0. 01). Subjects in the top tertile of legume intake had lower serum levels of high sensitive C-reactive protein (hs-CRP)، TNF-α and interleukin-6 (IL-6) as compared to those in the lowest tertile، even after controlling for potential confounders and dietary variables. No significant association was found between legume intake and serum amyloid A levels. High legume consumption is associated with low circulating levels of adhesion molecules and inflammatory biomarkers among Iranian women.

Investigation of the colloidal behaviour of protein-polysaccharide systems is becoming increasingly important to provide a foundation for their applications in areas such as production of biopolymer micro-and nano-particles، designing food analogues، and microencapsulation technology. The aim of the present study was to investigate the pH-induced critical transitions during associative phase separation between β-lactoglobulin (BLG) and tragacanthin (T). The formation of electrostatic complexes in BLG/T dispersions (0. 3wt. % total concentration; BLG: T ratio 2:1) was investigated as a function of pH (2. 00-6. 00) by spectrophotometry and particle size analysis. In addition، coupling of slow in situ acidification of the blend، with glucono-delta-lacton، and rheometry were used to monitor the structural transitions during the associative phase separation. The influence of salt type and concentration on the formation of micro-particles were also determined. The formation of soluble complexes started at pH ~5. 20، and at pH ~4. 85 the aggregation of intrapolymeric complexes occurred، followed by a bulk phase separation at pH ~4. 30. The data indicated that coacervation occurred at pH 4. 15. Finally، the mixture returned to a mono-phasic system at pH 2. 5. Particle size analysis showed that the assembled structures experienced a contraction process upon complexation. Rheometry provided deeper insights into the colloidal behaviour of the system and the results were in good agreement with quiescent pH-induced transitions established by HCl titration. The formation of the micro-particles was strongly salt-dependent. Under controlled pH conditions، electrostatic interactions between β-lactoglobulin and tragacanthin can be used to form a variety of biopolymer particles. These biopolymeric micro- and nano-particles may be used in the food industry as natural delivery systems or fat-replacers. Keywords: β-Lactoglobulin، Tragacanthin، Protein-polysaccharide interactions، Associative phase separation، Biopolymer micro-particles

Cardiovascular disease is the major cause of morbidity، mortality and disability in the world and Iranian population. Inflammation and oxidative processes are major risk factors ofatherosclerosis. Some evidence demonstrated antinflammatory effect of conjugated linoleic acids (CLA) and omega-3 fatty acids (ω-3 fatty acids). So the aim of this study was to evaluate the effect of CLA and ω-3 fatty acids supplementation on inflammatory and oxidative stress markers in atherosclerotic patients. In this study 90 volunteers who referred to Emam Reza Heart Clinic of Shiraz University of Medical Sciences were selected if they fulfilled the inclusion criteria. Participants were classified into 3 groups receiving 3g/d CLA، 1920mg/d ω3 or placebo for 2 months. C-reactive protein (CRP)، interleukin -6 (IL-6)، malondialdehyde (MDA) and glutathione peroxidase (GPx) were measured before and after supplementation. CRP measurement was done by a high sensitive Enzyme Linked Immunosorbent Assay and IL-6 assay was performed by Radioimmunoassay methods. GPx enzyme activity and MDA was measured byspectrophotometery. Data processing and statistical analysis were done using SPSS19 software and a p-value of <0. 05 was considered as statistically significant. hs-CRP level decreased significantly in both the ω3 and CLA group during the study (4. 43±4. 13 vs 1. 6±1. 41 and 7. 48±5. 64 vs 5. 95±5. 87) (p = 0. 01). IL-6 reduced significantly in ω3 groupralative to control (18. 59±11. 12 vs 13. 37 ± 9. 44) (p=0. 04) but in CLA group reduction in IL-6 levels was not significant (16. 13±10. 21 vs 12. 95±8. 1) (p=0. 06). GPx increased in CLA and ω3 groups (144. 57±56. 89 vs 174. 61±62. 8 and 125±46. 06 vs 171. 4±68. 90) (p=0. 001). MDA level decreased significantly in both the ω3 and CLA group (3. 98±1. 50 vs 2. 87±1. 55 and 3. 7±1. 77 vs 2. 4±0. 8) (p = 0. 001). Supplementation of diet with CLA and ω3 can have a beneficial effect on some indices of inflammatory and oxidative stress.

Rice bran، a by-product of the milling process، has attracted considerable attention because of its nutritional quality. Rice bran is a natural source of oil، carbohydrates، lignin، phenolic compounds، proteins، enzymes and vitamins، but it is usually used as animal feed. The aim of this study was to investigate the possibility of obtaining a rice-bran extract using an efficient environment-friendly method to be used for fortification of orange drinks. Rice-bran extract was obtained by putting rice under pressure at 120˚C to keep the water in the liquid phase. Samples were then prepared by adding the extract as an ingredient in the formulation of an orange drink and their physical and chemical characteristic and rheological behavior determined. Statistical analysis was done using the SPSS software، the statistical test being the Duncan test (p<0. 05%). Increasing therice-extract content in the formulation of the orange drink samples resulted in increases in the ash content، pH، turbidity، dry matter، and sediment and in a decrease in viscosity. ََRhelogically all the treatments resulted in a similar viscosity behavior of a pseudo-plastic fluid with a flow index less than 1. Adding rice-bran extract in the formulation of the orange beverage brought about changes in its physical and chemical properties. The rheological behavior of the samples containing the extract is changed in such a way that the rice bran-containing beverage changes from a Newtonian to a non-Newtonianfluid. Considering the nutritional characteristics of rice-bran extract، by using it in the formulation of orange beverage one can produce a new functional beverage with a higher nutritional value than ordinary orange juice.

Due to their antioxidant properties، vitamin E (VitE) and alpha-lipoic acid (ALA) may have a protective role against cardiovascular disease (CVD) risk factors، e. g.، insulin resistance (IR) and dislipidemia، in hemodialysis patients. The main objective of this study was to determinethe effects of dietary supplementation with alpha-lipoic acid and vitamin E، individually and combined، on insulin resistance and lipid profile in hemodialysis patients. This study was a randomized clinical placebo-controlled trial، including 85 patients (45 men and 40 women) from Shiraz hemodialysis centres. We examined the effects of a 2-month daily supplementation with VitE (400IU) and ALA (600mg)، individually and combined، on fasting blood sugar (FBS)، insulin، the HOMA index، and lipid profile (serum total، VLDL-، LDL- and HDL-cholesterol، and triglycerides). A placebo group was also included in the study. At the beginning and at the end of the intervention weights and heights of the patients were measured، body mass index (BMI) was calculated، dietary intake assessed، and blood samples were taken for analysis. Significant reductionswere observed in mean FBS (4. 2)، insulin (10. 4) and the HOMA index (1. 5) in theALA+VitE-supplemented group compared to the placebo group (P-values=0. 02، 0. 006، and 0. 002، respectively); changes in these parameters were not statistically significant in the groups supplemented with either one alone. Also، supplementation with VitE or ALA، either alone or combined، had no statstically significant effects on the lipid profile. Combinedsupplementation with vitamin Eand alpha-lipoic acid ALA canimprove insulin resistance in hemodialysis.

There are a few studies about wheat flour fortification with powdered Spirulina platensis microalgae to produce industrial cookies. The objective of this study was to investigate the effects of Spirulina platensis microalgae used in production of traditional Iranian cookies on their nutritional value، color and texture. Samples of cookies were prepared using S. pirulina platensis at a level (% w/w) of 0. 0، 0. 5، 1. 0 and 1. 5%. The protein، iron and poluunsaturated fatty acid (PUFA) contents of the samples were measured by microkjeldahl، atomic absorption and GC mass chromatography، respectively; the peroxide value in the four samples was also determined. Sensory evaluation (hedonic scale 1− 5) of the samples was made by 14 trained panelists. The iron، protein and γ-linolenic acid contents of the fortified cookies were higher، and their peroxide value lower، than the respective control values. With regard to sensory evaluation، cookie samples containing 1. 0% and 1. 5% S. platensis scored highest following the control sample (p<0. 05). It is possible to produce cookies fortified with1. 0-1. 5% S. platensis with desirable nutritional and sensory characterstics.

Spices and herbs have been added to foodstuffs since old times due to their medicinal، preservative and flavouring effects. They are، however، often contaminated with microorganisms. Gamma irradiation is currently used widely to eliminate microbial contaminations in foods. The aim of the study was to determine the effects of gamma irradiation on the antioxidant and antimicrobial activities of cinnamon (Cinnamomum zeylanicum).

Samples of cinnamon were exposed to gamma irradiation at doses of 10، 15، 20 and 25 kGy، followed by preparing hydroalcoholic (50% ethanol) extracts from them for sequence analysis. The antioxidant activity of the irradiated and control samples was measured by DPPH radical scavenging، ferric reducing power، and bleaching of beta-caroten، and the total phenolic content was also determined. The broth diluting method was applied for the determination of minimal inhibitory concentration (MIC) of E. coli and S. aureus. All tests were performed in triplicates، and the least significant difference (LSD) statistical test at α = 0. 01 was used to compare differences among the means.

Gamma irradiation had no adverse effects on antioxidant activities and total phenolic content of the samples. Only at doses more than 10 kGy did the radical scavenging activity of the cinnamon extract increase (DPPH test). With regard to the effect of gamma irradiation on antimicrobial activity، as compared to the control value، there was no statistically significant difference in the activity of irradiated samples up to a dose of 25 kGy.

Gamma irradiation treatment of cinnamon had no adverse effect on its antioxidant and antimicrobial activities. Gamma irradiation at doses up to 25 kGy seems to be appropriate for cinnamon.

Delayed muscle soreness occurs after resistance activity or training involving an eccentric component، and nutrition can affect theextent of muscle injury by playing a role in both protein synthesis and catabolism. The objective of this study was to to compare the effects of dietary supplementation with carbohydrate and protein at different proportions on injury indices of muscle after a session of eccentric resistance exercise. In this double-blind placebo-controlled study 24 non-athlete males (age21. 5 ± 2. 4 years، height 176 ± 4. 7 cm، weight 73. 6 ± 5. 4 kg، BMI 24. 3± 1. 9 kg/m2، body fat 16. 1±2. 5%) were divided randomly into 3 groups of 8، receiving a supplement of carbohydrate-plus-whey protein at a ratio of 1:3 or 1:4، or a placebo (aspartame). Serum creatine kinase (CK) andlactate dehydrogenase (LDH) were determined photometrically، and muscle pain was measured using a standard scale of PAS before، 24 and 48 hours after، an eccentric resistance exercise involving knee flexion. Both carbohydrate-plus-whey protein supplements caused statistically significant reductions in CK and LDH levels and muscle soreness compared with the placebo (p<0. 05)، although no significant differences were observed between the two supplements (p>0. 05). It is concluded that dietary supplementation with carbohydrate and whey protein at a ratio of 1:3 or 1:4 can bring about a reduction in muscle damage indices after eccentric resistance exercise. The optimum ratio، however، to be used in sports drinks and for recommendation to individuals starting exercise warrants further research.

Furan was classified as «possibly carcinogenic to humans» by the International Agency for Research on Cancer in 1995. The joint FAO/WHO Committee set the maximum permissible furan at 2 mcg/kg body weight/day in 2010. The furan content of coffee is high as compared to other processed foods. Considering the increasing trend of coffee consumption in Iran، this study was initiated to determine the furan content of different kinds of coffee powder available in Tehran Market by headspace liquid-phase microextraction coupled with gas chromatography mass spectrometry (HS-LPME-GC-MS). The e CCD mployed included 32 treatments at 5levels for 4 factors with8 replicates of center point. The furanic compounds from 66 different coffee samples were extracted by HS-LPME atoptimal extraction conditions (salt 0 gram، stirrer rate 700 rpm، extraction temperature 45°C، and extraction time 15 min). The effect of coffee brewing and coffee mix preparation on furanic compound content of coffee was also determined. The proposed method was validated by determining linearity، repeatability، recovery، enrichment factor، LOD، and LOQ. Determination of furan in coffee samples showed that there were significant differences (p<0. 05) in furan concentration of different coffees (prepared by different methods) and that preparation method was the most important factor influencing the furan content of coffee. The coffee brewing and preparation of instant coffee and coffee mixes reduced furanic compounds concentration except furfural. The lowest and highest concentrations of furan in commercial coffee products were10 and 6320 ppb، respectively. In the present work، a simple، fast micro-extraction method (HS-LPME) for extraction and pre-concentration of furanic compounds in coffee samples was developed and validated. The advantages of this method are reduced solvent use، low-cost equipment use، simple experimental setup، acceptable precision and accuracy، a high enrichment factor، and no matrix interference. Differences detected in the furanic compound contents in the coffee samples are due to different green coffee bean species، coffee production process (roasting condition (time and temperature)، time of degassing، and grade of grinding process). Brewing coffee in open systems can result in decreases in the content of these compounds to an acceptable level.

In Iran insufficient attention is paid to the processing methods and potential byproducts of dates. It is at least partly for these resaons that the wastage of this important food item is high. Consequently، research on the processing of date byproducts، such as date syrup، isessential. This study was carried out in order to obtain more information on the subject and find ways to improve date syrup-extracting conditions.

In order to determine the effects of pectinase on syrups obtained from various date varieties، two varieties، namely، Shahani and Mazafati dates were used، and the extraction of syrup was carried out reciprocally. The pH of the syrup was set at 4. 5 and the temperature at 45 C، the 2 pectinases، i. e.، Rapidase Smart and Rapidase Max C80 (DSM Company، Netherland) were added، and color، turbidity، dissolved solid materials (BX) and viscosity of the syrup were determined. The SPSS software version 19 was used for data analysis، the ststistical test being the multi-range Duncan test.

Rapidase Smart (used for syrup extraction) brought about increases in turbidity and dissolved solid materials (BX) and improved color in syrups obtained from both date varieties، while Rapidase Max C80 (used for clarification) caused decreases in these characteristics. Moreover، the treated syrup samples had a lower viscosity compared to the untreated ones، but no significant differences were found among the treated samples (p>0. 05).

Although syrup-extracting enzymes cause an increase in turbidity and improve color in date syrup، their use is recommended because theyincrease efficiency of extraction and decrease the viscosity of the syrup.

Inflammation plays a crucial role in the pathogenesis and progression of type Π diabetes، atherosclerosis، cardiovascular disease and metabolic syndrome (MetS). Despite high prevalence of MetS and its strong association with other chronic inflammatory diseases، the optimal dietary macronutrient composition to manage the inflammatory process in the MetS remains unknown. We aimed to review the evidence on the effects of variation in dietary macronutrient intakes on chronic inflammation in the MetS.

We searched PubMed/MedLine between 1990 and 2011،using the following keywords: macronutrient، high/low-carbohydrate،-fat،-protein، ketogenic، metabolic syndrome، chronic inflammation، and the surrogate inflammatory biomarkers. Clinical trials and cross-sectional and prospective studies were included in this investigation.

Dietary intakes of trans-fatty acids have been associated with elevated levels of inflammatory indices. Although strict restriction of dietary carbohydrates (ketogenic diet) has affected inflammatory biomarkers considerably، moderately-restricted carbohydrate diets were not different from low-fat diets in terms of their impacts on inflammation. High-protein diets do not seem to be suitable for alleviating inflammation، because of their probable deleterious effects on liver and kidney functions.

Sever restriction of dietary carbohydrates (similar to ketogenic diets) seems to be essential if one intends to influence the inflammatory process in the metabolic syndrome; moderate dietary carbohydrate restriction does not seem to affect inflammation. Lack of sufficient evidenceon the subject in different groups of patients and limitations in the design of current studies warrants further investigation in this field.