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Sorghum is the fifth most harvested crop worldwide, being the popped sorghum as one of the most common snacks in India and some Asian regions. Therefore, this study evaluated how the processing method influences the microstructure, volumetric and textural properties of popped sorghum microstructure, volumetric and textural properties. White sorghum "Paloma" variety (11% moisture) was assessed, which was popped using three processing methods: microwave, pan-frying, and hot salt-frying using three temperature levels. Volumetric and yield characteristics were evaluated for the popped kernels, as their microstructure and texture profile. The popped sorghum obtained through the hot salt-frying method had a microstructure composed of polygonal cells. Also, it showed the best volumetric characteristics (volume), good expansion index, and high process yield. Finally, the hot salt-frying method showed better textural features associated with the attributes of a satisfactory product for consumers.

Amylose is well known to be organized helically with six glucose per turn, allowing it to form complexes with various ligands. This interaction can be affected by the type of crystalline structure present in the starch sources. This study evaluated the effect of extrusion on the crystalline structure of starch during RS5 formation. Rice and potato starches were extruded at 100 °C and 15 rpm with 5% and 10% oleic acid (OA), then the physical, thermal, paste properties, and resistant starch content (RS) were evaluated. Potato starch extruded with 10% OA showed granules embedded in a gelatinized starch matrix. The X-ray revealed that rice (orthorhombic) and potato (hexagonal) structures remain unchanged even after extrusion. Differential scanning calorimetry (DSC) evidenced the formation of type IIa amylose-lipid complexes in OA treatments, where potato extruded with 10% OA had the highest enthalpy (0.9 J/g). Moreover, the extruded potato showed the highest pasting temperature (87.19 °C), supporting the complex formation. The RS was reduced from 15.8 (isolated) to 4.14 mg/100 mg (extruded 10% OA) in rice. For potato, RS decreased from 17 to 13 mg/100 mg (isolated and extruded 10% OA). Overall, these findings suggest a tendency in potato starch (ortho-rhombic) to interact with OA during the extrusion process, promoting a crystalline lamellae growth when extruded with 10% OA, therefore, changing their properties.

The aim of this study was to evaluate the effect of acid hydrolysis and succination upon single and a combination of both of them as a dual modification on the morphological, structural, thermal, and pasting profile of the achira starch in order to expand its potential food applications. The surface of achira starch granules was eroded with acid hydrolysis, while the succination resulted in the formation of pores or cavities, having a slight impact on the crystallinity and the gelatinization enthalpy. Succinated starch presented the lowest transition temperatures (To = 60.29 °C, Tp = 65.03 °C and Te = 69.86 °C) compared to other starches in this study. The succination increased the final viscosity (3808 cp) when compared with the native starch (3114 cp), while acid hydrolysis resulted in a decreased value (735 cp). These are desirable properties for its possible use as an additive in bakery industry processes.

This study evaluated the formulation of ethylcellulose oleogels as a fat substitute, based on oils with a high content of polyunsaturated fatty acids. Optimal processing conditions for canola, linseed, and chia oil oleogels were determined. The results showed that the oxidative stability was affected to a greater extent in chia oil oleogel, however, the addition of BHT improved the oxidative stability, mainly the peroxide value. Linseed and chia oil oleogels with a high content of polyunsaturated fatty acids (64.28 and 73.02 g/100 g, respectively) were obtained despite the reduction of these with respect to their oils, and no trans fatty acids were produced. Chia oil oleogels were shown to exhibit similar physical properties to linseed oil oleogels in terms of firmness (463.51 ± 7.42 g and 443.03 ± 7.14 g respectively) and rheological behavior. Such a structure led to a dominant elastic character of the oleogels to mimic the mechanical properties of animal fat.

Pulque is a Mexican alcoholic, probiotic beverage with shelf life of 3 days. The physicochemical, probiotic, and sensory properties of pulque depend on its content of lactic acid bacteria (LAB) and yeasts. The aim of this study was to apply ohmic heating (OH) in order to extend the shelf life of pulque without altering its properties. Pulque processed by conventional pasteurization (63 °C, 30 min) was used as control. Parameters such as electrical conductivity (0.22 S/m) and optimal pasteurization conditions by OH (65 °C, 5 and 7 min; 70 °C, 3 and 5 min) were determined. Shelf life was evaluated with these parameters during 22 days of storage at 4 ± 1 °C. A higher content of LAB (6.68 and 5.96 log10 CFU/mL) was obtained at 65 °C for 5 and 7 min, respectively, compared with conventional pasteurization (3.54 log10 CFU/mL). After 22 days, physicochemical properties (pH, color, and alcohol content) were stable for both methods of pasteurization. However, the pulque treated with OH had greater sensory acceptance. For the first time, OH was used to process pulque, and results revealed that is an effective technology for extending the shelf life until 22 days, preserving microbiological and physicochemical properties. Microorganisms as surviving the OH treatments were identified as Lactobacillus acidophilus, Lactobacillus kefiri, and Saccharomyces cerevisiae.

We studied the changes in the phytochemicals profile of two instant corn flours produced by different process: traditional nixtamalization process (TN) and by ohmic heating process (OH). The highest total phenolics content was found in the OH flours (OHF), which showed predominance of bound phenolics and free flavonoids compared with the TN flours (TNF). Ferulic acid measured by HPLC-DAD was the most abundant compound in its bound form in the OHF, but decreased by 57% in TNF. The insoluble fiber content was preserved by the OHF (17.49%) and the soluble fiber increased ∼65% compared with TNF. These data suggest that instant corn flours processed by OH preserves the phenolic profile and antioxidant profile similarly than flours processed by TN; furthermore, water waste was reduced significantly, and no effluents were produced in the ohmic heating process.

The nutritional, cooking and technological properties of the Tepary bean (TB) cultivated in Mexican northeast comparing to two common beans varieties (Pinto Americano and Black Jamapa) were evaluated in this study. Nutritional parameters evaluated of TB resulted significantly different from common beans varieties analysed, except lipid fraction. Cooking times of soaked (4 and 8 h) and non-soaked varieties varied significantly; TB shows between 55.1–80.49 min by cooking time. The textural profile analysis (TPA) of TB showed a significant reduction of hardness, chewiness and adhesiveness in soaked compared to non-soaked. In addition, TB presented a similar behaviour to Pinto Americano in TPA non-soaked and cooked and soaked 8h and cooked, except to adhesiveness. Technological properties of TB and resistant and non-resistant starch content showed significant differences between species. Due to, TB has nutritional, cooking and technological properties comparable to other edible legumes as common bean, mainly Pinto Americano variety.

Black garlic (BG) is obtained by the Maillard reaction under controlled conditions of temperature and humidity. This study describes the traditional processing (TT-BG) and the use of ohmic heating (OH) as pre-treatment (OH-BG) to improve time processing. Physicochemical composition and sensory properties were of particular interest in this study. The OH as a pretreatment causes the hydrolysis of fructans to fructose, which are degraded during storage under traditional treatment conditions (70 °C/94% RH) through the Maillard reaction causing the faster formation of compounds responsible for the color of black garlic compared to black garlic without pre-treatment. This reaction cuts down the time to attain the characteristic color of black garlic from 30 to 12 days. The 5-hydroxymethyl-2-furaldehyde (HMF) content was 3.6 times higher in OH-BG than in TT-BG. The polyphenol content and antioxidant capacity did not show differences between TT-BG and OH-BG, but their levels were superior to commercial sample. Both products (OH-BG and TT-BG) were sweet (36.8 and 31.6 °Bx, respectively) and had an excellent organoleptic acceptance (75 and 70%). These results highlight the potential of ohmic heating pretreatment in reducing the time to obtain good quality BG., Ríos-Ríos was supported by a scholarship from the Consejo Nacional de Ciencia y Tecnología (CONACYT-Mexico).

The popping process has been widely used as a technique for obtaining snacks. This study evaluated the effect of the popping process on the structural and thermal properties of sorghum. Seven varieties of sorghum were used. Raw sorghum grains were adjusted to 11% moisture and popped at 210 °C for 90 s with hot air. Microstructure, thermal and viscosity properties, and X-Ray and infrared spectrum were measured in raw and popped sorghum. The popping process produced an ordered honeycomb-like structure in the sorghum. The viscosity profile showed an increase in the thermal stability of popped sorghum. DSC measurements showed a starch gelatinization and a second transition about to 145 °C. XRD diffractograms display a reduction in the amplitude of the crystalline orthorhombic structure peaks. Finally, infrared indicated a change in the short-range structure and protein denaturation due to the popping process., Authors F.G. Castro-Campos and A.H. Cabrera-Ramírez thanks the “Consejo Nacional de Ciencia y Tecnología” (CONACYT-Mexico) for the financial support of their post-graduate position [Grant numbers: 712859 and 734975, respectively]. This research was supported by the FOPER-2018 and 2019 of the Universidad Autónoma de Querétaro.

The cognition of original qualitative attributes of native Peruvian chili peppers elucidate their potential industrial exploitation. There is a lack of scientific information about chili pepper physicochemical and nutritional attributes, that hampers their immediate industrial use. Therefore, the aim of the present study was to characterize twenty Peruvian chili pepper landraces in terms of structural and nutritional properties. In particular, the Bostwick consistency index of chili purees, dry matter, dietary fibers and pectin content were determined. In addition, the color and carotenoid profile of each landrace were studied. A wide range of consistency and stability were found, and partially explained by the dry matter, dietary fiber and pectin content. C. annuum landraces displayed the highest dry matter and fiber content. Moreover, different carotenoid profiles were observed, being β-carotene the most abundant in almost all the samples. Capsanthin was present only in red landraces, while yellow ones had low total carotenoid content. High Retinol Activity Equivalent levels were determined for red peppers, while high insoluble dietary fiber level was found in all the samples. Cluster analysis, including all the chili pepper attributes, showed no relation between taxonomical classification and chili peppers structural, sensorial, and nutritional characteristics. Unique features of studied chili pepper landraces presented in this work should be considered during their industrial processing. In this context, these results might be considered a starting point for processing design and for the proper valorization of this raw material.

Commercially, crab meat is obtained by hand-picking after a cooking process, followed by pasteurizing or canning. Jumbo lump is one of the pieces of meat obtained from the blue crab. The aim of this study was to evaluate the effect of the commercial cooking process (boiling and steaming) on the mechanical and functional properties of whole jumbo lump and the gels obtained from cooked and minced jumbo lump from blue crab (Callinectes sapidus). The gels were prepared combining the washing process and microbial transglutaminase. The boiling and steaming processes showed a different effect on the textural and color properties. Whole jumbo lump pieces cooked by immersion in boiling water showed a higher hardness value as compared to steamed jumbo lump pieces, suggesting a different internal structural. The cooking processes used in this study did not modify the water holding capacity, gelling capability, or color of the minced jumbo lump. The addition of microbial transglutaminase to washed minced jumb...

Current consumer trends emphasize the need for designing ready-to-use food that besides convenience render health benefits, including low calorie content and higher amounts of protein, fibers and antioxidants. The aim of this research was to assess the acceptance as well as the nutritional and bioactive compounds content of a snack bar elaborated with common bean and oat flour. A mixture design was used to generate 27 different combinations of ingredients that were evaluated in a ranking test to select the most preferred formulations. Protein, total flavonoids and antioxidant capacity were significantly higher (p

In this study, achira (Canna edulis) starch (AS), a non-conventional starch, was hydrolyzed using hydrochloric acid (7.5%) from 3 to 15 days to investigate the effect of long term acid hydrolysis on the evolution of the crystalline and double-helical structure changes, and its repercussion on the functionality. After 15 days, the degree of hydrolysis was 40.3 ± 0.8%. Micrographs revealed the granular structure loss after 6 days of hydrolysis. Acid hydrolysis decreased the crystallinity from 36.6 to 21.1% after 3 days but it increased to 27.0% after 15 days, while the degree of double helix and degree of order decreased after the acid treatment. Structural degradation of AS induced by the acid hydrolysis was reflected in the significant reduction of the enthalpy change of gelatinization and swelling, and the significant increase of the water solubility and water holding capacity, reaching maximum values at 9 (52.6 ± 1.0%) and 15 (266.4 ± 0.4%) days, respectively. Through the appropriate modification of the crystalline and double-helical structure by acid hydrolysis, the AS functionality can be regulated by adjusting the hydrolysis time, expanding the use of AS in the food industry.

Blending native starches is a feasible alternative for modifying the functional properties of starch dispersions. Granular interactions between starches lead to desirable properties that can be used for specific applications. Starch blends from amaranth (AmS) and achira (AS) were prepared at different proportions, and the pasting properties, flow curves and low-shear dynamic rheology were evaluated at 5, 7.5 and 10 g/100 g of solids. Granular interactions between starches were promoted when the solid content increased, affecting the formation of pasta. A polynomial model was used to predict the viscosity of the starch blends. The mechanical spectra showed that G′ and G″ had a slight dependence on the frequency. The incorporation of granules of AmS improved the stability of AS gels. Blending AmS and AS modified the rheological properties compared to pastes obtained from pure starches, mainly due to the concentration, size and granule interactions, resulting in low stability of the gels formed.

Sorghum, a competitive crop due to its agronomical advantages, has gained interest as functional food. Sorghum contains phytochemicals with health benefits and presents some antinutritional compounds such as condensed tannins (CTs). However, it is well known that CTs exhibit antioxidant capacity. This study evaluated the effect of Mexican nixtamalization on total phenols, CTs and antioxidant capacity using two varieties of sorghum. Different conditions of lime (0, 1 and 2%) and cooking time (20, 30 and 40 min) were tested to obtain the best treatment after optimization using multiple linear regression analysis, aiming to minimize the CTs content and maximize the antioxidant capacity. CTs were reduced at 27% in white sorghum and 90%, in red sorghum. Total phenols, flavonoids and antioxidant capacity had an inverse correlation with lime concentration and cooking time. The best conditions for preserving antioxidant capacity with low content of tannins were 1.13% of lime and 31.11 min cooking. The phenolic profile obtained by HPLC showed reductions in gallic and chlorogenic acids only in white sorghum, whereas catechin and quercetin decreased in both varieties. We concluded that nixtamalization effectively reduced CTs to safety intake values, allowing to preserve other phenolic compounds and antioxidant capacity.

Extrusion was used for obtaining corn masa. Particle size, Ca(OH)2 concentration, and tempering time had significant effects on the viscosity of extruded flours. Ground corn tempered for different periods of time (0.016–10 h) increased viscosity without application of heat. This behavior can be explained by the release of starches from the protein matrix. Viscoelastic properties of masas showed storage modulus (G′) > loss modulus (G″) for all samples. G′ and G″ increased as a function of tempering time, indicating higher water absorption capacity (WAC). The same behavior was found for Ca(OH)2 concentration, suggesting formation of cross-links between starch and polymers. Viscosity of masas modeled by the power law showed a value of n close to 0.1, suggesting that the dispersed solid phase was greater than the liquid phase. Index n and consistency coefficient K were associated with water absorption and viscosity, respectively. Regarding Ca(OH)2, the higher the Ca(OH)2 concentration, the lower the index n; ...

Ohmic heating (OH) is an emerging technology with potential for pasteurization and enzyme inactivation in mango pulp. This research aimed to investigate the effect of OH and conventional boiling treatment (CT) at moderate pasteurization conditions (72 °C, 2 min) on the physicochemical characteristics and the polyphenol oxidase (PPO) residual activity in Ataulfo mango pulp. Pulp's physical features, such as titratable acidity (TA) and pH did not show differences (p > 0.05) between treatments, whereas OH increased the apparent viscosity of mango pulp (10.26–15.64%). This effect was associated to a higher release of insoluble fiber. Both thermal treatments affected the color (ΔE values > 5) of mango pulp. PPO inactivation reached 95.7 ± 5.9% after 15 s with both thermal treatments. In silico molecular dynamics suggested that temperature and pH contributed to the PPO inactivation by inducing modifications in its catalytic site and altering the protein-substrate interaction. Our results indicate that OH is an effective technology to inactivate PPO at moderate pasteurization conditions (72 °C, 15 s), with minimal modifications on the physicochemical properties of Ataulfo mango pulp.

Two experiments were conducted to evaluate the effect of a lactic acid bacteria-based probiotic (FloraMax-B11®) against Salmonella enterica serovar Enteritidis intestinal colonization and intestinal permeability in broiler chickens. Experiment 1 consisted of two independent trials. In each trial, day-old broiler chicks were assigned to one of two groups: control + S. Enteritidis or probiotic + S. Enteritidis. At 72 h post-S. Enteritidis challenge, haematology and caecal content were evaluated for S. Enteritidis colonization. In Experiment 2, day-old broiler chicks were assigned to one of four groups: negative control; probiotic; control + S. Enteritidis; or probiotic + S. Enteritidis. At 72 h post-S. Enteritidis challenge, chickens in all groups were given an oral gavage dose of fluorescein isothiocyanate dextran (FITC-d). In both trials of Experiment 1, a significant reduction (P

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.

The kinetics of starch gelatinization is usually described as a first‐order reaction, that is, the rate of formation of gelatinized mass is assumed to be proportional to the unreacted amount. It is also assumed that the proportional constant, the reaction rate (k), has an Arrhenius‐type dependence on temperature. The equation derived from this model predicts that all the starch eventually gelatinizes at any given temperature for any k different from zero. However, it is well known that gelatinization only initiates above the so called “gelatinization temperature.” In this study it is employed an alternative model that properly describes the actual experimental behavior, which deviates considerably from the first‐order model prediction. The model introduces an empirical parameter that quantifies the extent of gelatinization when a starch‐water mixture is held at certain temperature for “long enough.” The gelatinization degree was evaluated by applying thermal treatments to 70% moisture‐content samples for 0, 0.5, 1, 3, 5, 7, and 10 min at several temperatures (61, 63, 65, 67, and 69°C). The gelatinization activation energy (EA) derived from the alternative model is 176 ± 10 kJ/mol. Since the proposed model closely reproduces the experimental behavior, it is suggested that this value better describes the actual process. The proposed model allows for the proper modeling of the starch‐gelatinization kinetics, which is relevant in starch gelatinization studies and in food processing industry.

In this study, the resistant starch (RS) formation, crystallinity, and double helical order of autoclaved (120 °C) normal (ANS) and high amylose (AHS) corn starches retrograded at ~4–26% of water content were investigated. ANS and AHS retrograded at ~25–26% of water content were more crystalline (~35–40%) and formed by more close-packed double helices (R1000/1022 cm−1 = 1.145–1.290). The highest content of RS (38.8%) was found in AHS retrograded at 25.52% of water content meanwhile in ANS, the maximum content of RS was 6.6% at 21.60% of water content despite its structural order was increased with the increase of water content. The recrystallization of amylopectin interfered with the formation of homogeneous crystalline structures of amylose preventing the formation of retrograded RS in ANS, while in AHS, a relationship between structure and RS formation was observed, suggesting that the close-packed double helices and the proportion of homogeneous amylose crystallites increased the resistance to enzymatic digestion.

Functional modifications of starch, such as paste properties, retrogradation, water absorption indexes, solubility, and swelling capacity, are induced by the amylose-lipid complex. This research comprehends the study of functional properties of extruded maize starch mixed with fatty acids (stearic acid, oleic acid, and maize oil) and the formation of amylose-lipid complexes. Maize starch with lipids (5 or 10 %), moisture (35 %) was extruded (single screw). Starch granule was modified by extrusion, to a lesser extent at 10 % of lipids, especially stearic acid, which covers starch granule surface. Viscosity decreased meaningfully with stearic acid addition. DSC showed both starch gelatinization enthalpy and amylose-lipid complex enthalpy for stearic or oleic acid, but it was just the first enthalpy for maize oil. X-ray diffraction showed orthorhombic crystals with or without the presence of lipids. Our results indicated that stearic acid yielded the highest amount of amylose-lipid complexes.

Popcorn is a healthy snack suggested by nutritionists. However, some countries in Europe, Asia, and South America have evaluated the use of sorghum as a popped cereal. Therefore, this study aims to evaluate the content of corneous and floury endosperm of sorghum and its influence in the popped sorghum quality. Five red varieties and three white varieties were evaluated. The physical and microstructural characteristics of the raw varieties were evaluated. The correlation matrix showed that physical properties such as the pericarp thickness, the hectoliter weight, and the type of endosperm are crucial to obtain popped sorghum. A high percentage of corneous endosperm and the size distribution of starch granules in the floury endosperm determine the popping ability of sorghum. The analysis of the principal components showed that the Paloma variety was the most suitable to obtain popped sorghum.

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 CaCO(3), 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 (Ca(2+), Mg(2+), Fe(2+), Zn(2+), Na(+) and K(+)) present in wood ashes, lime and salts used as raw materials. Correlation of (r = 0.85; p

A broad range of Peruvian chili peppers are available but not properly characterized. To increase the insight into their flavor compounds, a head space GC-MS fingerprinting (volatiles) and an HPLC-based profiling approach (pungency) was implemented to characterize twenty landraces (Capsicum annuum, C. baccatum and C. chinense). The data obtained was analyzed with powerful chemometric approaches to identify unique flavor compounds for each of the species and for each of the landraces within a specific species. The pungency profile and volatiles such as esters, terpenes and norcarotenoids distinguish Cerezo triangular (4) (C. annuum). Mainly esters provoked the separation between Chico (42), Cacho de cabra rojo (323), Amarillo de Chachapoyas (318) (C. baccatum), Arnaucho (60) and Miscucho amarillo (69) (C. chinense). This study demonstrates the potential of the integrated fingerprinting, profiling and a chemometric approach to extensively understand the unique flavor compounds in Peruvian chili peppers.

To evaluate the effect of different levels of citric acid (CA) combined with phytase and calcium levels in the diets of laying hens on the calcium and phosphorus (P) contents of eggs: yolk-albumen and shell, yolk color and egg quality. A study was conducted with 24-week-old laying hens fed with a diet based on sorghum and soybean meal with 2.7 Mcal of EM/kg, 15% crude protein, 3.25% calcium and 0.25% available P. The levels of CA, phytase and calcium were 0%, 0.6% and 1.2%; 0 and 300 units of phytase (PHYU)/kg; and 3.0% and 3.25%, respectively. Phytase was added as an ingredient into to the diets, contributing 0.1% P and 0.3% calcium. A completely randomized factorial experiment was performed with a 3 × 2 × 2 design and 4 replications. The CA increased (P < 0.05) the P in the shell, and the combination of 1.2% CA, 300 PHYU phytase and 3.25% calcium increased (P < 0.05) the calcium in the eggshell. There was a CA × phytase × calcium interaction (P < 0.05) affecting egg yolk pigmentation; there were no differences in egg quality. It was concluded that adding CA to the diets of laying hens increases eggshell calcium content, and improves the phytase response. 1.2% CA × Phytase × 3.25% calcium significantly increases shell calcium by 0.56 g. Under the conditions of the present investigation, it would imply greater resistance of the eggs to be broken in the handling from the farm to the sales centers and consumer. Phytase interacts negatively with 0.6% CA at low calcium levels to degrade the yellow pigmentation of the yolk.

The objective of the present work was to study the effect of annealing and concentration of Ca(OH)2 (lime) and calcium salts on the thermal and rheological properties of maize starch during an ecological nixtamalization process. Thermal and rheological properties of maize starch changed during the ecological nixtamalization process because of three main causes: the annealing phenomenon, type of calcium salt, and calcium salt concentration. In all treatments thermal properties (To, Tp, and Tf) of nixtamal starch increased owing to the annealing process, whereas the type of salt or lime increased thermal properties and decreased pasting properties in this order: CaCl2 > CaSO4 > Ca(OH)2 ≈ CaCO3. This behavior was because of the dissociation of each salt or lime in water. Anions (OH−) can penetrate much more easily into the starch granule and start the gelatinization process by rupturing hydrogen bonds. Additionally, amylose-lipid complexes were formed during the nixtamalization processes, as indicated by an ...

Electrospraying is a technique now applied for the production of food nanoparticles, nanofibres and nanocapsules, which could constitute a good alternative for the development of films. The goal of this work was to determine the electrospraying operation conditions and the zein concentration that would allow a film to be produced and also to evaluate the structural characteristics and barrier and thermal properties of films developed at different thicknesses. Results showed that films can be obtained by electrospraying, resulting possible to produce homogeneous films, without electrical arc formation during processing when using a 11.4% zein solution, an electrical voltage of 7.8–8.7 kV and a distance of 1.5 ± 0.5 cm between the nozzle and the deposit plaque. Regarding the effect of the production methods (electrospraying and casting) and the film thickness on film appearance, both variables had significant effect on colour parameters, observing a more yellowish colour (b* = 72.3 ± 6.8) and lower transparency (%T = 90.6 ± 0.21) at larger thicknesses (100 μm), and a smoother and more homogeneous surface (ESEM) when films were obtained by electrospraying. Water vapour permeability was only influenced by film thickness (1.51 × 10−08 to 3.11 × 10−08 g/s-m-Pa) in both methodologies. The glass transition temperatures (Tg) for electrospraying and casting films were different (222 °C and 231 °C respectively) and higher than that of zein powder (165 °C), indicating a possible change in the film structure due to the process. Under the process conditions tested in this work, electrospraying can be considered as an alternative technique to produce films.

The objective of this work was to study the formation of resistant starch (RS) in tortillas from an ecological nixtamalization process compared with the traditional nixtamalization process. The RS increased through all the steps of tortilla production. It was found that the increase of the RS corresponds mainly to the formation of RS5 (V-amylose-lipid complex), but in tortillas two major types of RS coexist: RS5 and RS3 (retrograded starch). In general, tortillas from the ecological nixtamalization process gave higher values of protein, lipids, total dietary fiber, insoluble fiber, soluble fiber, and RS compared with tortillas from the traditional nixtamalization process and commercial flour. The highest glycemic index (GI) occurred in the tortillas from commercial flour, whereas tortillas from 0.4% CaCO3 and 0.6% CaSO4 were classified as medium-GI (GI 50–70). Tortillas from 0.6% CaCl2 had the lowest value of GI. The ecological nixtamalization processes caused significant differences in quality and nutrit...

The objective of this study was to assess thermal, rheological and quality properties of grain, masa (ground nixtamalized corn), and tortillas made with high-oil maize hybrids and compare them with landraces. Grains of high-oil hybrids were harder (flotation index 10–36) with high onset, peak and final gelatinization temperatures, which were reflected in lower masa and tortilla yield. However, the tortillas had higher oil content (3.2–4.5 g/100 g) than those made with landraces (2.9–3.0 g/100 g). Tortillas made with the yellow hybrids were softer (1.8 N). Pepitilla had the highest viscosity in grain, masa and tortillas, reflected in greater water absorption and masa and tortilla yield (1.61 kg/kg maize). A close relationship was found between G′ and G″ and retained pericarp and oil content in masa; higher content of natural gums produced firmer masa with higher viscoelasticity. The high oil content in tortillas reduced their water absorption and starch swelling capacity but inhibited starch retrogradation, so they remained softer during storage.

Functional confectionery can be exploited as a vehicle for the protection of phenolic compounds (PCs) and for enhancing absorption during the gastrointestinal (GI) process. In this study, a confection containing 20% of mango bagasse (MB), gelatin and pectin was formulated. The PC profile, antioxidant capacity, in vitro bioaccessibility and apparent permeability (Papp) during mouth-stomach-intestine digestion (15, 30, 60, 120 min) and in vitro colonic fermentation (6, 12, 24 h) were evaluated for MB and the mango bagasse confection (MBC). HPLC-DAD analysis showed that mangiferin (830.69 μg g-1) was the most abundant compound in MBC. Total PCs (4.14 mg g-1), quercetin (244.83 μg g-1), and gallic acid (GA) (285.43 μg g-1) were highly bioaccessible mainly at the intestine at 60-120 min of digestion. GA was the most bioaccessible compound. Total flavonoids (TFs) and condensed tannins (CTs) had the maximum bioaccessibility in the mouth and stomach, respectively. For the permeability studies, PCs showed efflux rather than uptake in the intestine. Those compounds that exhibited intestinal absorption were mangiferin > GA > total PCs > TFs, whereas quercetin and CT absorption was negligible. The antioxidant capacity remained unchanged along the GI, mangiferin and quercetin being the most likely compounds to exert this activity. Overall results indicate that MBC has higher bioaccessibility, absorption and antioxidant capacity than MB, suggesting an effective protective role of gelatin and pectin, giving insight into the potential of MBC as a functional food.

The tyrosinase is a binuclear copper enzyme that catalyzes the oxidation of phenolics compounds to quinones in presence of molecular oxygen, which subsequently polymerized to dark brown pigments. To evaluate the effect of ohmic heating (OH) on the inactivation kinetics of Agaricus bisporus tyrosinase the independent variables were: electric field strength (25, 30, 35 V/cm), process time (0–15 min) and temperature (50–58 ± 1 °C). The conventional thermal treatment (CT) was used as a control. The results showed that the electric field decreased the time (D-value) required obtaining the same degree of tyrosinase inactivation at a target temperature compared to the CT. This indicates that the electric field acted synergistically with temperature to inactivate tyrosinase. The activation energy (Ea) calculated for the CT was 227.32 kJ mol−1, while for the OH they were 146.52, 135.14 and 124.87 kJ mol−1 for electric field strengths of 25, 30, and 35 V/cm respectively. In this study, a direct relationship between the Ea and the electric field is shown. Results demonstrated that the OH is an effective technology to inactivate tyrosinase, allowing it to be used in thermal process such as pasteurization or blanching.

The aim of this work was to study the effect of temperature on the functional properties of extruded corn flours compared to a flour produced by means of a traditional nixtamalization process. The extrusion treatments were as follows: temperature of 70°C, 75°C, and 80°C; moisture content of 45%, 55%, and 65% w/w; and particle size of 500, 800, and 1300 µm. According to the ANOVA, the temperature significantly affected the functional properties: the water solubility index (WSI), the water absorption index (WAI), adhesion, and relative viscosity. A temperature lower than 80°C favors high viscosity and suitable texture. The principal component analysis revealed that flours with a particle size of 1300 µm have pasting properties that are similar to those of nixtamalized flour, but with a high degree of retrogradation. The flour extruded at 75°C, with 800 µm particle size, and 45% moisture content showed WSI, WAI, and texture similar to those of nixtamalized corn flour, but with a lower viscosity.

Traditional nixtamalization is performed to produce corn flour and tortillas. This process has undergone several modifications for industrialization purposes. Extrusion is an industrially used process for nixtamalization and ohmic heating may be considered an alternative. For this study, a continuous ohmic heater was used to produce nixtamalized corn flour and the effects of the process parameters – process temperature, feed moisture, and screw speed – on the physicochemical and textural properties of dough and tortilla were reviewed. Data showed that the process temperature had a greater effect than the feed moisture on the resulting product, while screw speed did not appear to have any significant influence on this. Tortillas showed good quality characteristics because of good water absorption and retention during the process. The products obtained by continuous ohmic heating process show quality characteristics similar to those present in traditional corn flour products.

Extrusion is considered a high potential technology in the production of nixtamal corn flour (NCF); however, shear force and high temperature produce starch dextrinization, modifying the quality characteristics of NCF. This investigation evaluated the effect of feed moisture, temperature, calcium hydroxide and speed in a low-shear transport system (LSTS) on water absorption index (WAI), water solubility index (WSI), relative viscosity, pH and color of NCF. Feed moisture and temperature had a significant effect on most of the characteristics of the NCF, while speed of transport and calcium hydroxide did not. NCF obtained from the LSTS presented a higher WAI and a lower WSI, relative viscosity and luminosity than NCF produced by the traditional method; however, differences between them were not significant. Lack of difference in WSI between NCF produced by both methods indirectly show that LSTS produces a low dextrinization. Practical Applications The most common corn food products elaborated from nixtamal corn flour (NCF) are snacks, tortilla, porridge and tamal. The low-shear transport system (LSTS) may be used to produce NCF appropriate for any of these final products surpassing the extrusion-cooking process, which is mainly used to produce snacks. According to the results of this investigation, it is possible to use LSTS to obtain NCF with a lower degree of dextrinization, improving NCF quality.

The study evaluated the effect of time and fatty acid (FA) composition in eggs of laying hens supplemented with tuna oil (TO). Two hundred White Leghorn hens 30-week were divided into 5 treatments with 4 replicates of 10 birds each. Treatments were assigned randomly and consisted of 0%, 0.75%, 1.50%, 2.25% and 3% TO in commercial sorghum-soybean meal diets, in which the soybean oil was partially replaced. The experiment was conducted for 90 days. At days 28, 56 and 84 of the experiment, 10 eggs per replicate were collected for chemical analysis. Feed intake, egg production rate, egg weight, and feed conversion were not influenced by dietary treatment. FA content was significantly altered (P < 0.05) by TO, showing a progressive increase in egg n-3 FA (especially docosahexaenoic [DHA] and eicosapentaenoic [EPA] acids) when TO was added. Levels of EPA and DHA were higher (P < 0.05) in the egg lipids of TO fed hens than those in the control group. This was correlated (P < 0.05) with the concentration of TO in the diet. However, no significant differences were observed either in egg weight or percent of egg lay between groups. There was a high correlation (P < 0.05) between TO inclusion level in the diet and the incorporation of EPA (r = 0.96) or DHA (r = 0.92) into the egg yolk and an overall decrease in n-6 FA. There was a high correlation (P < 0.05) between TO inclusion level and the incorporation of linoleic acid (LA, r = －0.95) or arachidonic acid (AA, r = －0.96) into the egg yolk. The highest incorporation (P < 0.05) of total n-3 FA content in eggs was obtained with 3% TO/kg. This increase was proportional to TO inclusion levels in the diets (r = 0.95). The results indicate that the n-3 FA content in eggs can be increased by dietary supplementation with TO, and that TO can serve as a reasonable alternative feed ingredient in layer diets to produce a healthier choice of egg.

The aim of the present study was to evaluate the effect of feeding four levels of tuna oil on performance and fatty acid (FA) profiles of broiler chicken meat. 240 Ross broiler chickens were randomly assigned to 20 pens and divided into four treatments: 0%, 0.75%, 1%, and 1.25% of tuna oil. At 49 days, breast and legs-thighs muscles were processed for FA analysis. Concentrations of FA in legs and thighs meat were significantly higher when compared with breast meat. In both types of meats (breast and legs-thighs), the inclusion of 1.0% or 1.25% of tuna oil in the diet significantly increased (P < 0.05) the concentration of n-3 FA (especially docosahexaenoic and eicosapentaenoic acids). Fat in broiler breast contained a proportion of 29% saturated FA (SFA): 36% monosaturated FA (MFA): 35% polyunsaturated FA (PUFA); while legs and thighs meat had a proportion of 28% SFA: 38% MFA: 33% PUFA. The addition of tuna oil in the broiler diet significantly reduced the deposition of SFA, MFA, and PUFA in breast meat, while in legs and thighs these reductions were less noticeable. The significant reduction in the concentration of n-6 PUFA and the increment of n-3 PUFA were more evident in breast than in legs and thighs, and with the addition of 1% and 1.25% of tuna oil. The results of the present study suggest a difference in FA deposition attributable to supplementation with tuna oil. The addition of tuna oil could be recommendable to increase n-3 PUFA in both broiler chicken breast and legs-thighs meats, providing a healthier and functional chicken meat to consumer.

Se caracterizaron harinas de maiz nixtamalizadas (HMN) obtenidas por calentamiento ohmico (HCO), proceso tradicional (HPT) y harina comercial (HC) en su composicion quimica, capacidad e indice de absorcion de agua (CAA, IAA), indice de solubilidad (ISA), viscosidad, rendimiento, humedad y textura de las masas y tortillas. Las HCO presentaron diferentes grados de gelatinizacion de acuerdo a los resultados de IAA, CAA, ISA y viscosidad. Las masas y tortillas obtenidas de las HCO, presentaron mayor humedad (58,25 a 53,62 g/100 g) que la HPT (52,67 g/100 g), resultando en un mayor rendimiento de tortilla, con buena textura. El contenido de proteina de las HCO fue de 8,51 a 8,23%, superior a la HPT (7,95%). El contenido de fibra fue mayor en las HCO comparado con las HPT y HC (P

Kinetic parameters of thermal inactivation of pectin methylesterase (PME) in a partially purified mango enzyme extract were determined. The PME of mango partially purified by salting out showed different patterns of thermal inactivation, indicating the presence of a thermostable fraction at 70 °C and a thermolabile fraction at lower temperatures. The inactivation of the thermostable fraction exhibited a linear behavior that yielded a z-value of 9.44 °C and an activation energy (Ea) of 245.6 kJ mol-1 K-1 using the Arrhenius model. The thermostable mango PME fraction represented 17% of total crude enzyme extract, which emphasizes the importance of residual enzyme activity after heat treatment.

Approximately 80% of sorghum phenolic compounds are linked to arabinoxylans by ester bonds, which are capable of resisting the digestion process in the upper gastrointestinal tract, compromising their bioaccessibility and biological potential. The aim of this study was to evaluate the effect of the extrusion process on the content of phenolic compounds in sorghum bran and its impact on phenolic compounds and antiradical and anti-inflammatory capacity. Results revealed that the extrusion process increased total phenol content in sorghum bran compared to nonextruded sorghum, particularly for extrusion at 180°C with 20% moisture content (2.0222±0.0157versus3.0729±0.0187 mg GAE/g +52%), which positively affected antiradical capacity measured by the DPPH and TEAC assays. The percentage of inhibition of nitric oxide (NO) production by RAW cells due to the presence of extruded sorghum bran extract was significantly higher than that of nonextruded sorghum bran extract (90.2±1.9%versus76.2±1.3%). The results suggest that extruded sorghum bran could be used as a functional ingredient and provide advantages to consumers by reducing diseases related to oxidative stress and inflammation.

Previously, our laboratory has screened and identified Bacillus spp. isolates as direct-fed microbials (DFM). The purpose of the present study was to evaluate the cellulase and xylanase production of these isolates and select the most appropriate Bacillus spp. candidates for DFM. Furthermore, an in vitro digestive model, simulating different compartments of the gastrointestinal tract, was used to determine the effect of these selected candidates on digesta viscosity and Clostridium perfringens proliferation in different poultry diets. Production of cellulase and xylanase were based on their relative enzyme activity. Analysis of 16S rRNA sequence classified two strains as Bacillus amyloliquefaciens and one of the strains as Bacillus subtilis. The DFM was included at a concentration of 10(8) spores/g of feed in five different sterile soybean-based diets containing corn, wheat, rye, barley, or oat. After digestion time, supernatants from different diets were collected to measure viscosity, and C. perfringens proliferation. Additionally, from each in vitro simulated compartment, samples were taken to enumerate viable Bacillus spores using a plate count method after heat-treatment. Significant (P 0.05) DFM-associated reductions in supernatant viscosity and C. perfringens proliferation were observed for all non-corn diets. These results suggest that antinutritional factors, such as non-starch polysaccharides from different cereals, can enhance viscosity and C. perfringens growth. Remarkably, dietary inclusion of the DFM that produce cellulase and xylanase reduced both viscosity and C. perfringens proliferation compared with control diets. Regardless of diet composition, 90% of the DFM spores germinated during the first 30 min in the crop compartment of the digestion model, followed by a noteworthy increased in the intestine compartment by ~2log10, suggesting a full-life cycle development. Further studies to evaluate in vivo necrotic enteritis effects are in progress.

Water molecules modify the properties of biodegradable films obtained from hydrophilic materials. Most studies dealing with thermal, mechanical and barrier properties of hydrophilic films are carried out under one relative humidity (RH) condition. The objective of this work was to evaluate the effect of the moisture content on the thermal, mechanical and barrier properties of chitosan films under several RH conditions. Microclimates, obtained with saturated salt solutions were used for conditioning samples and the properties of the films were evaluated under each RH condition. Chitosan films absorbed up to 40% of moisture at the higher RH studied. The percentage of elongation and the water vapour permeability increased while tensile strength, Young's modulus and glass transition temperature decreased, when the moisture content increased. The results suggest that the water molecules plasticized the polymer matrix, changing the properties when the films were in contact with high RH environments.

Approximately 50% of the original whole fruit mass, after citrus processing for juice, consist of the peel, membranes and seeds. Citrus residues consist mainly of insoluble fiber (celluloses) and a small proportion of soluble fiber (hemicelluloses and pectin). For this reason, citrus residues could be considered as a potential high fiber ingredient that is used for food industry. In this study, lemon residues were extruded to modify and increase their soluble fiber fraction. Surface response methodology with six central points and six axial points was used to evaluate the changes in dietary fiber fractions in lemon residues. The independent variables studied were extrusion temperature (from 59.77 to 110.63°C), moisture content of the sample (from 33.18 to 66.82%) and screw speed (from 3.18 to 36.82). The extrusion process increased the soluble fiber from 38.60% in unprocessed lemon residues to 40.00 to 50.01% in extruded samples. The highest content of soluble fiber was 50.00% when operating conditions were high in temperature (100°C), low in moisture content (40%) and low in screw speed (10 rpm). The results of this study indicate that extrusion is a process that has the capability to transform insoluble fiber to soluble fiber in lemon residues. Key words : Lemon residues, extrusion, dietary fiber.