Research and Innovation in Food Science and Technology
Year:2020 | Volume:8 | Issue:4 |Papers Count:8

β-Glucans which are found in a variety of natural sources such as yeast, mushrooms, bacteria, algae, barley and oat show different biological effects. They are composed of D-glucose units linked by β-glycosidic bonds to each other. Adsorption of fungal toxins such as aflatoxin by β-glucan has been widely considered in recent years. Aflatoxins are a group of naturally-occurring carcinogens that are known to contaminate different human and animal foodstuffs. Aflatoxin B1 is the most genotoxic hepatocarcinogenic compound among all types of the aflatoxins. The efficiency of adsorption of fungal toxins is directly related to the molecular structure, extraction method and source of β-glucan. Fungal derived β-glucan consists of β (1-3) bonds in main and β (1-6) at lateral branching point, with the specification of short shoulder length, has high ability to adsorb fungal toxins. In this study, for the first time, the efficiency of various extraction methods of β-glucan from stem cell wall of bottom mushroom (Agaricus bisprous) was measured and the ability to adsorb aflatoxin B1 was evaluated. The results showed that although the yield of β-glucan from acid based extraction was higher than other methods (20. 5%), the hot alkaline extracted β-glucan could adsorb and discard 90. 2% of aflatoxin B1 from contaminated samples based on HPLC analysis.

The objective of the present study was to investigate the effect of concentration of osmotic solution (30, 45 and 60%, w/w), temperature osmotic solution (30, 40 and 50° C), immersion time (4, 5 and 6 h) on water loss (WL), solids gain (SG), weight reduction (WR), vitamin C content, shrinkage, rehydration ratio (RR), and color indexes (L, a, b) during osmotic dehydration-drying of turnip slices. Response surface methodology (RSM) was also used to find out the optimum condition. The results showed that during osmotic dehydration of turnip samples, the variables of temperature of osmotic solution, solution concentration and time of immersion had significant effects on mass transfer parameters (WL, SG, and WR), vitamin C content, shrinkage, RR, and color index (L). Optimal conditions of osmotic dehydration for turnip were found to be: solution temperature of 45  C, osmotic solution concentration of 58. 29, and immersion time of 20 min. Under these conditions, the amounts of WL, SG, WR, shrinkage, rehydration ratio (RR), vitamin C content, and color indexes (L, a, b) were 83. 10, 12. 91 and 70. 19%, 27. 76, 4. 19 and 11. 64 (mg/100 g solids), 33. 85, 25. 49 and 15. 91, respectively. The results of this study can be used in the minimal processing of turnips slices using osmotic dehydration and subsequent drying of samples.

Reduction rolls play an important role in the process of flour production and increasing the quality of flour used in baking industry is considered as the most important factor to improve the qualitative and nutritional qualities of bread. So the aim of this study was to evaluate the effect of removing C1A, C1B, C2, C3 and C5 reduction rolls on the physicochemical properties of the flour and rheological properties of dough and the selection of the most effective rolls in milling process in a completely randomized design (P≤ 0. 05). The results showed that two samples of flour that Also the sample, which C3 reduction rolls was removed, had the lowest gluten content (25%), gluten index (70), and zeleny sedimentation volume (17 mL). And the water absorption, development time, stability, and valorimeter number of the dough had the greatest reduction in this sample. Therefore, according to the results, it was found that by removing the C3 reduction roll in milling process, the physicochemical properties of the flour and the rheological properties of dough were strongly weakened. In the next step, the Barbari bread was produced by the flour obtained from this sample and control and its characteristics were examined. The results showed that the hardness of the sample by removing C3 reduction roll was higher (more than 35%) than the control sample during 2 and 72 h after baking. Also, the control had the highest score of overall acceptance in sensory evaluation. According to the results of this study, removing the C3 reduction roll, had the most effect on the quality of flour, dough and final product than the other roll in milling process.

Walnuts with essential and unsaturated fatty acids from omega-3 group, are considered as one of the most important dried fruits with nutritional value. Genotypes 25 and 29 (superior walnut genotypes) were selected to investigate the effect of modified atmosphere packaging on the beneficial compounds of their kernels oil. Walnut kernels were packaged under modified atmospheric conditions into a 90-μ m metalized plastic. After the oil cold extraction and purification of walnut kernels, the quantitative and qualitative composition of fatty acids was measured. The percent of fatty acids, aflatoxin content, peroxide index, iodine value, acidity and sensory evaluation of samples were determined in the 0-day and during one year storage. The results showed that the unsaturated fatty acids content are predominant in walnut kernels oil, and the linoleic acid is the dominating fatty acid. The saturated fatty acids content was less than 10%. The aflatoxin content of genotypes 25 and 29 were measured 0 and 5 ppb, respectively. The moisture content and the peroxide value were determined 1. 55-4. 32% and 0. 48-4. 65 meqO2/kg, respectively. The highest level of acidity was observed in the 25 genotypes. The peroxide index, titratable acidity, and weight loss increased with the increasing of storage time, while the iodine value decreased. Totally, the packaged genotype 25 in the PA/PE/PA/PE/Aluminum foil films under modified atmospheric containing 5-6% O2, 15% CO2 and 79-80% N2 is recommended due to the high quality of chemical and organoleptic properties and the lack of aflatoxin in the walnuts kernel.

By increasing consumer awareness about food safety and quality, there is a high demand for the preservative (synthetic)-free foods and use of natural products as preservatives. Plants are the main source of antimicrobials and contain many essential oils that have preservation effect against different microorganisms. The effect of natural orange peel oil on the chemical and microbiological and sensory properties of plum fruit roll ups was investigated during 15 days. The result of the Tensile strength tests plum fruit roll ups showed that adding orange peel to plum fruit roll ups significantly (P<0. 05) increased the tensile strength. At the end of storage of all samples, with orange peel oil the lowest pH content and highest acidity level were observed in the sample with 0. 5% orange peel oil and no mold and yeast were observed in any of the samples. The sample with 0. 5% had a maximum amount of lactic acid bacteria and the sample with 0. 1% orange peel oil had a minimum amount of lactic acid bacteria. The results showed that sample with 0. 5% orange peel oil had minimum number of total counts of bacteria and Control sample had a maximum amount of total counts of bacteria. The analysis of variance did not show any significant difference in plum fruit roll ups. According to the results of the analysis of variance, the highest texture, taste and aroma score belonged to the control sample. From the results, it can be deduced that due to the antimicrobial properties of orange peel essence and its positive effects on tissue characteristics, it can be used as a natural preservative in the plum fruit roll ups.

In this study, central composite design was used to predict microbial changes, volatile nitrogen basic (TVB-N), sensory analysis and also the freshness factor of silver carp (Hypophthalmichthys molitrix) fillet packed in vacuum at 0, 6 and 12 ° C for 5, 10 and 15 days optimized for the state-Ease Design Expert software. There was a significant difference between the treatments at time and temperature in the fillets of silver carp (P<0. 05). The two parameters of Inosine monophosphate (IMP) and inosine (HxR) showed a decreasing trend with increasing time and temperature (P<0. 05). Freshness and sensory analyses were in optimal mode in short time (5 days). In this test, the predicted values were consistent with a satisfactory percentage of 78%. The observations showed a good correlation between the results obtained by the experimental method and the predicted values by the statistical method. The models studied had R2 and R2-adj coefficients of approx. 1, indicating that the experimental model used was able to predict fillet quality changes with low error percentage. The success of this can improve kinetic models in the food industry, so its application can help sustain food products.

Lipid oxidation and microbial growth are the most important factors affecting the quality and corrosivity of the meat in refrigerated storage conditions. In this study, the effect of using chitosan, Medlar concentrate, ginger essential oil alone and in combination with each other on improving the quality and shelf life of chicken meat kept in the refrigerator was investigated. 8 groups in this study during 12 days were stored at refrigerator and Microbial (aerobic mesophilic & Psychotrophic Plate count) and chemical (PV, TBA, TVB-N) and. sensory parameters were measured at days 0, 4, 8 and 12. Total phenol and reducing power tests were also performed to evaluate the antioxidant properties. Based on the results of GC/MS, the major compounds of ginger essential oil were α-Zingiberene (36. 54%), -Sesquiphellandrene (16. 45%) and trans-γ-Cadinene (10. 27%) were formed. The results of this study showed that the chitosan-coated treatment containing 2% ginger essential oil and medlar concentrate, decreased the microbial parameters significantly (P<0. 05) as compared to control group during the storage period (P<0. 05). the oxidation indices of chicken meat samples had significantly fewer changes (P<0. 05), had the strongest antioxidant and sensory effect on other groups during storage. The results of microbiological, chemical and sensory analysis of this study showed that the effect of chitosan coating containing 2%ginger essential oil and medlar concentrate was effective in increasing the shelf life and quality of chicken meat for 12 days during storage in the refrigerated condition.

Glazing process can improve the baked texture and overall quality of bread. In this study, the effects of traditional glazes (water, oil, cheese powder, xanthan gum) on the physicochemical and sensory parameters of sorghum gluten-free bread were compared with Lepidium sativum seed gum. Specific volume, porosity, water activity, moisture, firmness and sensory parameters of breads were evaluated. Results showed cheese powder had the lowest moisture and vegetable oil treated samples had the lowest water activity. Lepidium sativum seed gum and xanthan gum provided the high effect on specific volume and porosity. Evaluation of crumb firmness implicated water, Lepidium sativum seed gum diminished the bread staling and these treated samples had the lowest firmness. Application of glazing ingredients did not have any significant (P>0. 05) effect on odor and taste. Lepidium sativum seed gum as a novel glaze was more effective than xanthan gum and its application was better than the usual glazes to improve the crust and overall quality of gluten-free bread.