Comparison of Properties of Breads Enriched with Omega-3 Oil Encapsulated in β-Glucan and Saccharomyces cerevisiae Yeast Cells

  Background and objective: Flaxseed oil, as a potential source of polyunsaturated fatty acids, is susceptible to oxidation. Yeast cells of Saccharomyces cerevisiae and β-glucan can be used as biocompatible and biodegradable matrices for the protection of this nutritious oil from oxidation in foods enriched with omega-3 fatty acids. The aim of this study was to investigate quality properties of breads containing encapsulated and free flaxseed oils. Materials and methods: Flaxseed oil was encapsulated in either yeast cells or β-glucan. Functional wheat bread samples were prepared using unencapsulated and encapsulated flaxseed oils. These were compared with control samples in terms of dough rheological and bread quality parameters. Results and conclusion: Encapsulation significantly increased dough rheological properties (G′ and G″ values), firmness and density and decreased lightness, compared to control samples. Breads, containing flaxseed oil encapsulated in yeast cells, showed a lower peroxide index and a higher α-linolenic acid value, compared to two other samples containing oil samples. This showed a better protection of unsaturated fatty acids against deleterious oxidation reactions. Results of this study indicate that addition of microencapsulated flaxseed oil into breads helps preserve sensory properties of the control sample, compared to breads fortified with free flaxseed oil. Conflict of interest: The authors declare no conflict of interest

Effects of Microbial Transglutaminase and Fermentation Type on Improvement of lysine Availability in Wheat Bread: A Response Surface Methodology

Background and objective: Lysine-glutamine crosslink formation catalyzed by microbial transglutaminase is supposed to affect improvement of lysine availability in wheat bread. Present study is done to investigate the effect of microbial transglutaminase and fermentation type in improvement of the lysine availability of wheat bread.Material and methods: Lysine-fortified wheat breads were formulated using response surface methodology with composite-face central design. Statistical models were used to predict the impact of defatted soy flour level (0-50% w w-1), microbial transglutaminase level (0-1.6% w w-1) and fermentation type (yeast or mixed fermentation based on sourdough). Further information was provided on the individual role of independent variables in nutritional and structural characteristics of optimized formulation and blank and control samples. Experiments were carried out in triplicate and the mean values were analyzed using one-way analysis of variance and Tukey’s test.Results and conclusion: The suggested formula contained 26.64% w w-1 of defatted soy flour and 0.55% w w-1 of microbial transglutaminase, which was fermented using sourdough-based mixed fermentation and provided 0.16 mg 100 g-1 of available lysine and 2.09 cm3 g-1 of specific volume. The highest lysine chemical score (22.79±0.16), essential amino acid index (35.31±0.37) and biological value (26.79±0.02) and the lowest lysine loss during the baking process seen in optimized formulation verified the effectiveness of microbial transglutaminase in lysine fortification of defatted soy flour/wheat breads (P≤0.05). Considering rheology parameters and textural analysis, microbial transglutaminase treatment increased elastic modulus and β-sheet structure. These structural changes decreased final products digestibility, which can increase using mixed fermentation based on sourdough.Conflict of interest: The authors declare no conflict of interest

Effect of Substitution of Sugar by High Fructose Corn Syrup on the Physicochemical Properties of Bakery and Dairy Products: A Review

High fructose corn syrup (HFCS) is commonly found in soft drinks and juice beverages, as well as in many pre-packaged foods such as breakfast cereals, baked goods and dairy desserts. Historically, sucrose (table sugar) was primarily added to processed foods and beverages as the sweetening agent. In recent years, the use of HFCS has significantly increased in popularity due to its sweetness, ability to enhance flavor and shelf life, and its low cost. HFCF made by enzymatic isomerization of glucose to fructose was introduced as HFCS-42 (42% fructose) and HFCS-55 (55% fructose) and opened a new frontier for the sweetener and soft drink industries. Using a glucose isomerase, the starch in corn can be efficiently converted into glucose and then to various amounts of fructose. Hydrolysis of sucrose produces a 50:50 molar mixture of fructose and glucose. The primary difference is that these monosaccharides exist free in solution in HFCS, but in sucrose bonded together. The disaccharide sucrose is easily cleaved in the small intestine, so free fructose and glucose are absorbed from both sucrose and HFCS. The advantage to food manufacturers is that the free monosaccharide in HFCS provides better flavor enhancement, stability, freshness, texture, color, pourability, and consistency in foods in comparison to sucrose. The development of these inexpensive, sweet corn-based syrups made it profitable to replace sucrose (sugar) and simple sugars with HFCS in our diet. In the present study, the replacement of sucrose with HFCS and its effect on the functionality and organoleptic properties of different food products were reviewed

Preparation and Characterization of Maltodextrin Microcapsules Containing Walnut Green Husk Extract

In recent years, the field of natural antimicrobial and antioxidant compounds is one of the main research topics in the food industry. Application of agricultural residues is mainly cheap, and available resources are receiving increased attention. Walnut green husk is one of the agricultural residues that is considered as natural compounds with biological properties because of phenolic compounds. In this study, maltodextrin 10% was used for microencapsulation of walnut green husk extract. At first, the extract was examined to consider extraction yield, total phenolic compounds, and antioxidant activation. The results showed the extraction yield of 81.43%, total phenolic compounds of 3997 [mg GAE/100 g], antioxidant activity [DPPH] of 84.85% for walnut green husk extract. Antioxidant activity is about 75%-81% and by DPPH. At the next stage, microencapsulation was done by spry-drying method. The microencapsulation efficiency was 72%-79%. The results of SEM tests confirmed this microencapsulation process. In addition, microencapsulated and free extract was more effective on gram-positive bacteria’s rather than the gram-negative ones. According to the study, walnut green husk can be used as a cheap antioxidant and antimicrobial compounds due to sufficient value of phenolic compounds

Gluten-free products in celiac disease: Nutritional and technological challenges and solutions

In celiac patient exposure to even only a small amount of gluten can lead to malabsorption of some important nutrients including calcium, iron, folic acid, and fat-soluble vitamins because of small-intestine inflammation. A strictly followed gluten-free (GF) diet throughout the patient's lifetime is the only effective treatment for celiac disease; however, elimination of gluten from cereal-based product leads to many technological and nutritional problems. This report discusses different substitutes to replace gluten functionality and examines the economic and social impacts of adherence to a GF diet. Better knowledge about the molecular basis of this disorder has encouraged the search for new methods of patient treatment. The new and common GF sources and different challenges encountered in production and consumption of these products and different solutions for improving their properties are discussed in this review

Characterization of microcapsule containing walnut (Juglans regia L.) green husk extract as preventive antioxidant and antimicrobial agent

Background: Walnut green husk (WGH) extract has been known as potential preventive and therapeutic antioxidants and antimicrobials due to its high polyphenol content. In this study, preparation of spray dried WGH extract-loaded microcapsules by maltodextrin and its blending with two other natural biodegradable polymers, pectin, or alginate were investigated. Methods: In this study, encapsulation efficiency (EE), total phenol content (Folin–Ciocalteu reagent method), antioxidant (DPPH scavenging assay) and antimicrobial activities (agar well diffusion method) structural (SEM and FTIR studies), and release properties of WGH extract-loaded microcapsules were investigated. Results: High retention of phenolic content in microcapsules indicated the successful encapsulation of WGH extract. Addition of biopolymers to maltodextrin matrix has a positive effect on EE and other properties of microcapsules. The microcapsules prepared with mixture of maltodextrin and pectin had higher EE (79.35 ± 0.87%) and total phenolic (TP) content (56.83 ± 1.04 mg gallic acid equivalents [GAE]/100 g) in comparison to maltodextrin and alginate mixture (EE: 75.21 ± 0.24%, TP content: 54.33 ± 1.53 mg GAE/100 g) and maltodextrin only matrix (EE: 72.50 ± 1.00%, TP content: 50.67 ± 1.35 mg GAE/100 g). Extract-loaded microcapsules also showed nearly spherical structure, good antioxidant (with the percentage DPPH inhibition ranged from 75.17 ± 1.42% to 80.87 ± 2.29%), and antimicrobial properties (with mean inhibition diameter zone ranged from 7.76 ± 0.86 mm to 11.53 ± 0.45 mm). Fourier transform infrared analyses suggested the presence of extract on microcapsules. The in vitro extract release from microcapsules followed an anomalous non-Fickian diffusion mechanism with almost complete release. Conclusions: WGH extract microcapsules can be used as novel and economic bioactive phytochemical and therapeutic agents to prevent oxidation and microbial activity