Sustainable Process for Tortilla Production Using Ohmic Heating with Minimal Impact on the Nutritional Value, Protein, and Calcium Performance.

The nixtamalization process used for tortilla production entails extended processing time and generates pollutant effluents. Ohmic heating (OH) is an emerging technology that uses an alternating electric current for rapid and uniform food heating and mitigates effluent concerns. However, gaps exist in nutrient bioavailability studies. In this work, we assessed OH's impact on tortilla nutritional value, protein, and calcium using a rat model. Twenty-five male Wistar rats were fed one of four diets for 21 days: raw corn (RC) as an experimental control, OH-processed tortillas (OHTs), traditionally processed tortillas (TPTs), commercial tortillas (CTs), and a casein diet (CD) as a growth control. Despite similar protein and macronutrient profiles, OH significantly enhanced insoluble fiber content. The weight gain sequence was OHTs > TPTs > CTs > RC. OHTs exhibited superior protein digestibility (88.52%), which was 3% higher than other diets. The serum albumin (2.63-2.73 g/dL) indicated moderate malnutrition due to the tortilla's lower protein content. Nonetheless, the protein efficiency ratio (1.2-1.74) showed no significant difference from TPTs. Bone characteristics and fracture strength resembled the tortilla-fed groups, surpassing RC. X-ray diffraction and scanning electron microscopy confirmed that the OHT and TPT diets improved male rat bone thickness and crystallinity. The findings suggest the potential for OH as an eco-friendly tortilla production method, maintaining nutritional value comparable to traditional methods.

Gallic, ellagic acids and their oral combined administration induce kidney, lung, and heart injury after acute exposure in Wistar rats.

Gallic (GA) and ellagic (EA) acids are present in foods, medicinal plants, teas, and dietary supplements. An acute toxicological study was conducted by oral administration of both compounds alone (200, 1000, and 2000 mg/kg) and combined (2000 mg/kg) and their effects on the electron transport chain (ETC) and the ROS production in kidney mitochondria further evaluated. All treatments induced a dose-dependent heart, lung, and kidney injury. However, the intensity of these effects varied according to the substance, with greater cardiac and renal toxicity for EA and pulmonary injury for GA, while the combination attenuated the toxicity of the isolated molecules. All substances inhibited the activity of complexes II, III, and IV of the ETC from renal mitochondria. However, no changes were observed regarding mitochondrial ROS production. These compounds have a non-negligible inherent deleterious potential, so their uncontrolled use at high doses (≥200 mg/kg) could cause undesirable effects.

The 5-HT1A receptor agonist, 8-OH-DPAT, attenuates long-lasting pain in imiquimod-induced psoriasis in mice.

Psoriasis pain is a common symptom underestimated and rarely evaluated in psoriasis clinical trials. This work aimed to investigate whether the development of secondary chronic allodynia and hyperalgesia in the imiquimod (IMQ)-induced psoriasis mice model could be modulated by anti-inflammatory agents and compound 48/80 (C48/80) and to determine whether the activation of 5-HT1A receptor modulates these nociceptive behaviours. C57BL/6 male mice were treated with 5% IMQ for 7 days. The paw withdrawal responses to von Frey filaments (10 and 250 mN) were used to assess the allodynia and hyperalgesia. Nociceptive behaviours were also evaluated using ketorolac 15 mg/kg s.c., adalimumab 10 mg/kg s.c. and C48/80 10 mg/kg i.p. Then, the serum serotonin and the impact of 8-OH-DPAT (1 mg/kg s.c), a 5-HT1A receptor agonist, on long-lasting pain were examined. Mice receiving IMQ showed enhanced nociception, which decreased with all tested compounds. The serum serotonin in the IMQ group showed a significant decrease (947.042 ng/ml) regarding the control group (1143.68 ng/ml). The pretreatment with 8-OH-DPAT alleviated pain-related behaviours. These results suggest that the long-lasting pain resulting from psoriasis inflammation is also associated with the serotonergic system. The 5-HT1A receptor should be further explored as a potential therapeutic target for psoriasis pain modulation.

Mathematical Model for Describing Corn Grain Dehydration Kinetics after a Nixtamalization Process.

In this research, the mathematical model associated with the hydrothermal dehydration process of Nixtamalized Corn Grains (NCG) with different Steeping Time (ST) values, allows the fitting of experimental data with initial moisture M0 and the equilibrium moisture ME as a function of Isothermal Dehydration Time (IDT). The moisture percentage for any time t and dehydration rate (isolines M(t) and isolines vI respectively) of the NCG is shown by means of matrix graphics as a simultaneous function of IDT and ST. The relationship between initial dehydration rate v0 and initial moisture M0 establishes as a function of ST. Also, the mathematical model associated with the solution of the second Fick's law allows calculating the diffusivity rate vk (H2O molecules out of NCG) and verify that the rate of change in moisture and the dynamical proportionality constant k has a non-linear dependence on the IDT and that k is directly proportional to Deff. The k values strongly relate to ST and the calcium ions percentage into NCG according to solubility lime values into cooking water (or nejayote) as a function of decreasing temperature when ST increases.

Effect of nixtamalization processes on mitigation of acrylamide formation in tortilla chips.

Acrylamide can be generated from food components during tortilla chips frying. Thus, the aim of this research was to study different nixtamalization processes as traditional (TNP) with lime [Ca(OH)2], ecological (ENP) with CaCO3, classic nixtamalization (CNP) that uses wood ash and extrusion (EXT) with no Ca+2 source on mitigating the acrylamide formation in deep-fat frying tortilla chips. Acrylamide quantification was done through HPLC-UV. Lower acrylamide content in tortilla chips was for CNP with 46.3 µg/kg, followed by TNP with 55.0 µg/kg, ENP with 694.6 µg/kg and EXP with 1443.4 µg/kg. Differences in acrylamide values among samples can be related to effect of cations (Ca2+, Mg2+, Fe2+, Zn2+, Na+ and K+) present in wood ashes, lime and salts used as raw materials. Correlation of (r = 0.85; p <0.0005) was observed in color of tortilla chips, moisture, texture, blisters, and oil with acrylamide. Nixtamalization process is an effective and inexpensive strategy for acrylamide mitigation.

Investigation of the Antibacterial Activity and Subacute Toxicity of a Quercus crassifolia Polyphenolic Bark Extract for its Potential Use in Functional Foods.

Oak wood is used in barrels for wine aging. During aging, polyphenols are transferred from the barrels to the liquid. Although the bioactivity of oak polyphenols in wines has been extensively studied, no investigation exists on their toxicological properties, which limits their use as functional safe ingredients for other products. In this work, the chemical composition of a polyphenolic extract of Quercus crassifolia bark (QCBe) was studied by GC-MS. Its antibacterial properties on probiotic and pathogenic bacteria and its subacute-oral toxicity were determined as a way to understand the potential impact from its addition to fermented food as a functional ingredient. QCBe shows a selective inhibition of Escherichia coli compared with Lactobacillus bulgaricus and Streptococcus thermophylus. According to the toxicity evaluation, the subacute no-observed-adverse-effect-level was achieved at 11 mg/kg bw/day, whereas the subacute lowest-observed-adverse-effect-level for kidney damage was at 33 mg/kg bw/day. These results suggest that, given the fact an adverse effect was observed after subacute administration of this extract, further longer term toxicological studies are needed to provide sufficient safety evidence for its use in humans. PRACTICAL APPLICATION: Mexico's yogurt market is growing which creates opportunities for the development of some yogurt products as functional foods. As a first step to evaluate its potential use in yogurt formulation, the antibacterial effect of a Quercus crassifolia polyphenolic extract (QCBe) on probiotic bacteria and its subacute-oral toxicity in rats were studied. A low inhibition on probiotic bacteria growth was observed after QCBe addition to Lactobacillus bulgaricus and Streptococcus thermophylus cultures. Exposure to QCBe for a subacute duration resulted in renal injury in rats at dosages greater than or equal to 33 mg/kg/bw/day. This adverse effect indicates the importance of performing further long-term toxicological assessments prior to the addition of QCBe to a food like yogurt, which is regularly eaten by consumers.

Effect of lactating sows' diet supplemented with cactus (Opuntia ficus-indica) on feed intake and reproductive and productive post-weaning performances.

The effect of cactus (Opuntia ficus-indica) added to the diet of lactating (21 days of lactation) sows on voluntary feed intake, and its impact on the productive and reproductive post-weaning performance was evaluated. Data collected of 72 farrowings from 37 hybrid sows were analyzed during 12-month period. The sows were divided into two groups: (i) control group (CG; n = 18 sows), sows fed only with commercial feed, and (ii) experimental group (EG; n = 19 sows), sows fed with commercial feed plus cactus supplement. The variables evaluated were blood glucose (BG), daily feed intake (DFI) and total feed intake (TFI), loss of body weight (LBW), weaning-estrus interval (WEI), and subsequent litter size (SLS). Data analysis was carried out using fixed effects models. A nested effect was found for farrowing number (FN) into of group and an interaction group × season on the analyzed variables (P < 0.001). EG observed lower levels of BG with 47.0 ± 7.9 mg dL-1 pre-prandial and 56.1 ± 5.9 mg dL-1 post-prandial at the 10th day of lactation (P < 0.05). DFI and TFI were higher in the sows of the EG independently of the FN and season (P < 0.05). No differeces were observed on the nested effect of FN into group on the levels of BG (P < 0.05). Autumn showed the higher TFI: 121.4 kg-1 sow-1 (P < 0.05). Sows from CG 3rd farrowing and from EG 4th farrowing observed higher LBW (13.8 and 6.9%, respectively) (P < 0.05). Summer showed a higher LBW with 12.7% for CG and 8.2% for EG (P < 0.05). EG showed a lower WEI (5.5 days) and greater SLS up to 1.8 piglets more depending upon the season (P < 0.05). The lactating sow's diet supplemented with cactus can counterbalance the negative effects of lactational hypophagia due to reduction on levels of BG during lactation and an increase on DFI and, therefore, improves performance of LBW, WEI, and SLS.

Quantification of Phenolic Compounds and In Vitro Radical Scavenging Abilities with Leaf Extracts from Two Varieties of Psidium guajava L.

Guava leaf (Psidium guajava L.) extracts are used in both traditional medicine and the pharmaceutical industry. The antioxidant compounds in P. guajava leaves can have positive effects including anti-inflammatory, anti-hyperglycemic, hepatoprotective, analgesic, anti-cancer effects, as well as protecting against cardiovascular diseases. In the present study, phenolic compounds and in vitro antioxidant capacity were measured in extracts obtained with polar and non-polar solvents from leaves of two varieties of guava, Calvillo Siglo XXI and Hidrozac. The quantity of total phenolics and total flavonoids were expressed as equivalents of gallic acid and quercetin, respectively. Hydroxyl radical, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and Oxygen Radical Absorbance Capacity using fluorescein (ORAC-FL) in vitro tests were used to assess the radical scavenging abilities of the extracts. The total phenolics were higher in the aqueous fraction of the variety Calvillo Siglo XXI, while in the Hidrozac variety total phenolics were higher in the acetone and chloroform fractions. Total flavonoids were higher in all fractions in the variety Calvillo Siglo XXI. Total phenolics showed a highly positive correlation for ORAC-FL, and a moderately positive correlation with hydroxyl radicals. Finally, total flavonoids showed a slightly positive correlation for ORAC-FL and hydroxyl radicals. Both varieties of guava leaf extract showed excellent antioxidant properties.

Extruded snacks from whole wheat supplemented with textured soy flour: Effect on instrumental and sensory textural characteristics.

The quality of extruded snacks can be affected not only by processing conditions, but also by some factors like the concentration and type of ingredients incorporated in their formulation and the working conditions used. Although the process conditions have been established with measurable textural properties, sensory qualities have not been correlated with these responses in expanded extruded snacks made with added functional ingredients. Therefore, in this study the effect of adding textured soy flour (TSF) and whole wheat flour (WWF) to refined wheat flour in the production of extruded snacks and expanded with hot air was evaluated. A response surface design using two levels with five central points was applied to obtain the best combinations of functional ingredients added, holding the parameters of the extrusion process and moisture of treatments. Some texture characteristics and sensory analysis were used as response variables, such as, hardness, fracturability, toughness, crispness, granularity, and chewiness. Likewise, the rate of expansion was evaluated. The results showed that the level of substitution of WWF, especially levels of 15%, had a significant effect on the hardness perceived by the panelist during sensory evaluation. The TSF at concentrations of ≥15%, favored the fracturability and crispness of the samples. It was found that the best expansion index was with the combination of 5% TSF and 15% WWF. Although a correlation between instrumental and sensory tests carried out on the extruded snacks expanded was not found. PRACTICAL APPLICATIONS: The physical characteristics of the extruded snacks such as expansion, hardness, and density are important parameters in terms of consumer acceptability of the final product as well as their functional properties. In other words, the appearance and texture are two of the most important attributes that can be seen in snack foods. In particular, the texture can be measured by intrinsic tests: objective (instrumental) and subjective (sensory). That is because the instrumental analysis provides parameters such as firmness, brittleness, consistency, chewiness, among others, when subjected to different stress, strain, and strain rates at the snacks. Similarly, sensory analysis, allows us to see features that include mechanical attributes (concerning the reaction to the applied force), geometric attributes (concerning the shape, size, and orientation of the particles within the food), and attributes related to the perception of moisture or fat content.

Nixtamalization Process Affects Resistant Starch Formation and Glycemic Index of Tamales.

Tamales were prepared with 3 nixtamalization processes (traditional, ecological, and classic) and evaluated for chemical composition, starch properties, and glycemic index. Resistant starch (RS) in tamales increased 1.6 to 3.7 times compared to raw maize. This increment was due to the starch retrogradation (RS3) and amylose-lipid complexes (RS5) formation. Tamales elaborated with classic and ecological nixtamalization processes exhibited the highest total, soluble and insoluble dietary fiber content, and the highest RS content and lower in vivo glycemic index compared to tamales elaborated with traditional nixtamalization process. Thermal properties of tamales showed 3 endotherms: amylopectin retrogradation (42.7 to 66.6 °C), melting of amylose lipid complex type I (78.8 to 105.4), and melting of amylose-lipid complex type II (110.7 to 129.7). Raw maize exhibited X-ray diffraction pattern type A, after nixtamalization and cooking of tamales it changed to V-type polymorph structure, due to amylose-lipid complexes formation. Tamales from ecological nixtamalization processes could represent potential health benefits associated with the reduction on blood glucose response after consumption.

Electrochemical Study and Characterization of an Amperometric Biosensor Based on the Immobilization of Laccase in a Nanostructure of TiO2 Synthesized by the Sol-Gel Method.

Laccase amperometric biosensors were developed to detect the catechol compound. The laccase enzyme (LAC) immobilization was performed on nanostructures of (a) titania (TiO2); (b) titania/Nafion (TiO2/NAF) (both immobilized by the sol-gel method) and a third nanostructure, which consisted of a single biosensor composite of Nafion and laccase enzyme denoted as NAF/LAC. The Nafion was deposited on a graphite electrode and used to avoid "cracking" on the matrix. The TiO2 particle size was an average of 66 nm. FTIR spectroscopy vibration modes of different composites were determined. The electrochemical behavior of the biosensor was studied using electrochemical spectroscopy (EIS) and cyclic voltammetry (CV). The biosensor based on TiO2/NAF/LAC presented the best electro-chemical properties with regard to sensitivity, stability and detection limit after a period of 22 days.

Effect of incorporating prebiotics in coating materials for the microencapsulation of Saccharomyces boulardii.

The objective of this study was to microencapsulate Saccharomyces boulardii using the emulsion technique. To microencapsulate the yeast, alginate sodium blended with inulin and mucilage from Opuntiaficus-indica was used as a coating material. The textural properties of the gels formed by the encapsulating materials and the in vitro viability of the yeast strain in the simulated conditions were studied. Textural profile analyses of the gels revealed differences (p < 0.05) in hardness because alginate produced stronger gels, whereas the incorporation of other hydrocolloids with alginate decreased gel strength and resulted in a more uniform, cohesive gel matrix. When alginate was blended with mucilage and inulin, encapsulated yeast presented higher counts and more viable cells, as compared to free yeast following 30 days of storage at 4 °C. Encapsulated and free yeast had 76.1% and 63.3%, respectively, of cell viability after 35 days of storage.

As (V) biosorption in an aqueous solution using chemically treated lemon (Citrus aurantifolia Swingle) residues.

UNLABELLED: The use of biosorbents to remove metals and metalloids from contaminated water systems has gained great usage in various parts of the world. The objective of the current study was to test lemon peels as biosorbents for As (V). Lemon peels were chemically characterized and arsenic contact experiments were performed to determine the adsorption capacity of the peels using different empirical models. The model that fit the experimental data was the Lagergren empirical model with a correlation coefficient of R= 0.8841. The results show that lemon peels were able to retain 474.8 µg of As (V)/g of biosorbent. PRACTICAL APPLICATION: Lemon agro-industrial waste can be useful in the removal of heavy metals, such as arsenic, from aqueous media.