Food associated diseases pose significant public health threat in the United States. Health risks... more Food associated diseases pose significant public health threat in the United States. Health risks associated with food-borne pathogens drive the need for constant monitoring of food products. An efficient method that can diagnose food-borne pathogens rapidly will be invaluable and in high demand. In this study, we showed the feasibility of a novel rapid detection platform based on fluorescence imaging/detection that combines a user-friendly, portable loop mediated isothermal amplification (LAMP) reaction device and a smartphone-based detection system. The proposed platform was used to detect Staphylococcus aureus which is one of the most important food-borne pathogen especially dairy products. The complete protocol is quicker; the reaction is performed under isothermal conditions and completed in 1 h or less. Experimental results show that LAMP assays were tenfold more sensitive than PCR-based detection. The proposed smartphone detection system was able to detect and quantify LAMP assay samples containing three different concentrations of S. aureus from 10 9 CFU/mL down to 10 3 CFU/mL. The present proof-of-concept study demonstrated that this platform offers a portable, easy to use method for measuring target pathogens with LAMP amplification. Food-borne pathogens are defined as biological agents that cause food-borne illness; they can be either viruses, bacteria and eukaryotes like funguses, protozoa or helminths 1. Every year, the Food and Drug Administration (FDA) reports the outbreaks associated with food-borne pathogens; for instance, in 2020, it reported the contamination of Escherichia coli, Listeria monocytogenes and Cyclospora in clover sprouts, Enoki mushrooms and bagged salad, respectively (FDA 2020). Health risks associated with food-borne pathogens drive the need for constant monitoring of food products. For microbial pathogen detection, the conventional method is bacterial growth on a culture medium then on selective agar; it sometimes involves biochemical or serological testing. This process has some disadvantages because it is time consuming, laborious and detection of non-culturable pathogens is not possible 2. By following the conventional methodology, the detection of E. coli O157 takes around 3 days, Salmonella 4-6 days and Vibrio parahaemolyticus around 7 days 3. For this reason, new techniques emerged which provide faster, more reliable and sensitive results; some of the most widely used are the polymerase chain
Jujube, commonly known as the Chinese date, is a nutritious fruit with medicinal importance. Fres... more Jujube, commonly known as the Chinese date, is a nutritious fruit with medicinal importance. Fresh jujube fruits have a shelf life of about ten days in ambient conditions that can be extended by drying. However, nutrition preservation varies with the drying method and parameters selected. We studied total phenolic content (TPC), proanthocyanidins (PA), vitamin C, cyclic adenosine monophosphate (cAMP), and antioxidant activities in jujube fruits dried with freeze-drying (FD), convective oven drying (OD) at 50 °C, 60 °C, and 75 °C, and sun drying (SD) with FD as a control. The cultivars used for this study were ‘Capri’ and ‘Xiang’ from Las Cruces in 2019, and ‘Sugarcane’, ‘Lang’, and ‘Sherwood’ from Las Cruces and Los Lunas, New Mexico, in 2020. Freeze-drying had the highest of all nutrient components tested, the best estimates of mature jujube fruits’ nutrient contents. Compared with FD, the majority of PA (96–99%) and vitamin C (90–93%) was lost during SD or OD processes. The retent...
Given consumer trends propelling a movement toward using plant protein in the food industry and s... more Given consumer trends propelling a movement toward using plant protein in the food industry and searching for alternative protein ingredients by the industry, this study aimed to assess the influence of factors such as protein concentration, medium pH, and the presence of a divalent ion (Ca2+) upon the rheological properties such as viscosity change and gel formation of dispersion proteins extracted from quinoa, black beans, and lentils. A solution of each protein was prepared by varying its concentration (2.5%, 5.0%, and 10%), the pH (5.0, 7.0, and 9.0), and the incorporation of calcium chloride (0.0% and 1.0%). Each obtained solution was subjected to rheological tests to determine the parameters: consistency index (K), flow behavior (n), the storage (G’) and loss (G’’) modules, and the phase shift angle (δ). The results demonstrate that the incorporation of Ca2+, the shift in protein levels, and the decrease in pH modified the rheological behaviors of proteins, which were also inf...
Muchos trabajos demuestran que los productos vegetales no solamente son fuentes de energía y nutr... more Muchos trabajos demuestran que los productos vegetales no solamente son fuentes de energía y nutrientes sino también fuentes de compuestos conocidos como fitoquímicos, que juegan un importante papel en la prevención de enfermedades como el cáncer, afecciones cardiovasculares y neurodegenerativas. Por otro lado, el aumento en la producción de manzana, determina también un aumento de la producción destinada al procesamiento industrial. En este sentido el conocer el contenido de de ciertas sustancias como polifenoles, antocianinas permiten conocer su potencial de uso industrial, como por ejemplo para la elaboración de jugos. En base a esto los objetivos del presente trabajo fueron realizar una caracterización físico-química de tres variedades de manzana; una de ellas de cultivo tradicional y muy extendido en Brasil y las otras dos mutaciones de esta última, de reciente explotación comercial. Fueron medidos al momento de cosecha la firmeza de la pulpa, acidez titulable (AT), los sólidos solubles totales (SST), el índice de yodo-almidón, los parámetros CIE "L*", "a*" y "b*" del color, polifenoles, antocianinas y azúcares reductores totales y vitamina C. Según los resultados, la variedad Fuji Kiku presentó una mayor firmeza de pulpa, AT, SST y vitamina C. En relación al color, la variedad Fuji Suprema mostró una coloración roja más intensa y mayor contenido de antocianinas. No fueron encontradas diferencias en los polifenoles y azúcares reductores totales. Palabras-clave: polifenoles totales; vitamina C; azúcares reductores; antocianinas; uso industrial.
The objective of this research was to evaluate the effect of the content of cottonseed meal (Goss... more The objective of this research was to evaluate the effect of the content of cottonseed meal (Gossypium hirsutum) and the processing variables on the functional properties and the content of gossypol of an extruded feed for sheep (Ovis aries). The diet was balanced according to the requirements of fattening Dorper sheep breed under 1 year. The extrusion process was optimized using a surface response methodology, with four independent variables: temperature in the last heating zone (120–160°C), moisture content (14–18%), screw speed (120 rpm–180 rpm), and cottonseed meal content (9 g–27 g 100 g−1), in a single screw extruder. The optimal food had 27.25% crude protein, 4.24% crude fat, 12.21% crude fiber, 46.95% nitrogen-free extract, and 9.35% ash. The composition of essential amino acids in the optimal diet was 1.00 g kg−1 of lysine, 1.25 g kg−1 of phenylalanine, 2.04 g kg−1 of leucine, 0.87 g kg−1 of isoleucine, 0.98 g kg−1 of threonine, 1.15 g kg−1 of valine, and 0.65 g kg−1 of his...
Gold fish (Carassius auratus) being an omnivorous fish was chosen as the candidate fish. Fingerli... more Gold fish (Carassius auratus) being an omnivorous fish was chosen as the candidate fish. Fingerling of C. auratus 2.34 gm after acclimated to laboratory condition for a period of 15 days were used in various studies. Five feeding types with 35% dietary protein level and with varying levels of algal meal were prepared and used. The fish were divided in to 5 groups. Group I was fed on Ulva reticulata free diet. Fish belonging to groups II, III, IV and V were fed on diets with 2, 4, 6 and 8% of Ulva reticulata supplementation respectively for 40 days. At the end of the experimental period growth, proximate composition, haematological parameters and carotenoid content were analyzed. It can be conclusively deduced from this study that Ulva reticulata had positively improved growth performance, haematological parameters and coloration in gold fish C. auratus. Reasons could be the high nutrient and mineral profile and carotene and chlorophyll a, b content of Ulva reticulata. This study suggests that U. reticulata can be included as an ingredient of gold fish diet up to 8%. Owing to the presence of disease resistance imparting antibacterial substances in the algae gold fish remained active and healthy and were free from bacterial infection, during the period of investigation. Antibacterial activity of U. reticulata on the tested fish pathogens indicates the scope of using extracts of U. reticulata an immuno-prophylactic for health management in the culture of Gold fish. Based on the results of this study, it was concluded that short term feeding had no adverse effect on gold fish but long term effect needs future research. Future work should focus on digestibility coefficients of different nutrient classes in U. reticulata prior to inclusion in formulated diets.
Several parameters, including particle size, solvent, temperature, and extraction method, affect ... more Several parameters, including particle size, solvent, temperature, and extraction method, affect phenolic compounds' extraction yield from a plant matrix. Considering the wide availability of sugarcane bagasse (SCB), this study analyzed the effect of different extraction methods and geographical origins on the yield, quality, and antimicrobial activity of phenolic compounds from SCB extracts. Samples from three geographical locations (Veracruz, Mexico; Santa Rosa, Texas, USA; and St. Mary, Louisiana, USA) were analyzed. Extraction was performed using an orbital shaker or ultrasonic bath at various times at a fixed temperature of 50°C, with 90% ethanol or methanol. The highest yield (5.91 mg GAE) was obtained using an orbital shaker for 24 h with 90% methanol as the solvent. HPLC-MS identified desferrioxamine b, baicalein, madecassic acid, and podototarin at different concentrations in all three SCB samples. The antimicrobial activity of these compounds was tested against Escheri...
ABSTRACT Agglutinating compounds are commonly used to improve the physical quality of aquafeeds. ... more ABSTRACT Agglutinating compounds are commonly used to improve the physical quality of aquafeeds. An evaluation was done of the effect of the agglutinating compound sodium alginate on the functional properties of aquaculture fish feed produced by extrusion. Meals containing one of four sodium alginate concentrations (0, 0.5, 1.5 and 2%) were extruded in a simple-screw extruder at 120 °C, 20% moisture content and a 1:1 compression ratio, extruding each treatment in duplicate. Expansion index values ranged from 1.11 to 1.12 with no differences (P > 0.05) between the diets containing sodium alginate. In contrast, the different sodium alginate levels had positive (P < 0.05) effects on water absorption index values (2.24 to 2.79 g/g), water solubility index values (10 to 12.94%), sinking velocity (6 to 8.56 cm/s) and hardness (1.98 to 3.31 N). Maximum hardness (3.31 N) was produced in the 2% sodium alginate diet. The highest sodium alginate level tested (2%) had the most appropriate physical and functional properties for an extruded fish meal-based (62%) aquaculture fish feed.
The ability for nitrate accumulation in potato tubers as affected by mineral fertilisation (N, K2... more The ability for nitrate accumulation in potato tubers as affected by mineral fertilisation (N, K20 and MgO), genotype and the site of cultivation was studied in a three-year-long field experiment. Fertilisation with potassium chloride and potassium sulphate increased nitrate concentration in the tubers while additional magnesium fertilisation reduced nitrate concentration. Significant differences in nitrate concentrations were observed in potato tubers depending on genetic conditions as well as on the cultivation location (with the same soil and climatic conditions, varieties and tillage). The nitrate content decreased as the result of storage at 4 ~ Concentration of these ions in tubers of table and industrial potatoes did not exceed Acceptable Daily Intake level determined by WHO.
Flor de Mayo M38, Pinto Villa and Bayo Victoria beans were stored under accelerated conditions fo... more Flor de Mayo M38, Pinto Villa and Bayo Victoria beans were stored under accelerated conditions for aging at 40 1C and 60% RH for 3 months. Following adjustment of moisture to 24, 26 and 28 g water/100 g solids, they were extruded at 165, 185 and 205 1C at a constant screw speed. Water absorption index (WAI) and bulk density of extrudates were measured. Feed humidity did not affect the evaluated properties. Storage conditions, temperature and cultivar were the parameters that influenced the evaluated properties. Higher value for WAI was obtained in aged beans, independently of cultivar, temperature and feed humidity used. The bulk density was similar for aged and not aged beans, but at the highest temperature it was lower for aged beans. This fact indicates that bean storing and interaction of temperature have important influence on the final quality of extrudates.
Extruded snacks were prepared from flour blends made with taro and nixtamalized (TF–NMF) or non-n... more Extruded snacks were prepared from flour blends made with taro and nixtamalized (TF–NMF) or non-nixtamalized maize (TF–MF) using a single-screw extruder. A central composite design was used to investigate the effects of taro flour proportion in formulations (0–100 g/100 g) and extrusion temperatures (140–180 °C) on the following indices: expansion (EI), water solubility (WSI), water absorption (WAI) and fat absorption (FAI). Moreover,
Journal of the Science of Food and Agriculture, 2002
Maize, wheat, amaranth, rice and soybean were screened for protein content. Alcoholsoluble (A1 an... more Maize, wheat, amaranth, rice and soybean were screened for protein content. Alcoholsoluble (A1 and A2) and glutelin (G1 and G2) fractions were isolated and compared in terms of their amino acid and protein compositions. The average proportions of nitrogen content between total alcohol-soluble proteins (TASP) and total glutelins (TGlu) in the pseudocereals amaranth and soybean were about 1.8:26.9 and 14.9:12.3 respectively. In the cereals maize and wheat these proportions were 47.8:33.2 and 44.7:31.2 respectively. The sum of essential amino acids was 47.6 and 60.3 g per 100 g protein in amaranth and soybean respectively. The highest contents of methionine, lysine and arginine were found in the pseudocereals. The relatively high content of essential amino acids shows that pseudocereals could be used as a nutrient substitute for cereals.
In vitro and in vivo studies of the health and nutritional properties of durian (Durio zibethinus... more In vitro and in vivo studies of the health and nutritional properties of durian (Durio zibethinus Murr.) were compared with snake fruit (Salacca edulis Reinw.) and mangosteen (Garcinia mangostana). Dietary fibers, minerals, and trace metals were comparable. Total polyphenols (mg of GAE/100 g of FW) and flavonoids (85.1 ( 6.1) were significantly higher (p < 0.05) than in snake fruit (217.1 ( 13.2 (mg of CE/100 g of FW)), durian (309.7 ( 19.3 and 61.2 ( 4.9), and mangosteen (190.3 ( 12.1 and 54.1 ( 3.8). Antioxidant activity (µM TE/100 g of FW) of durian measured by DPPH and ABTS assays (228.2 ( 13.4 and 2016.3 ( 81.1) was significantly higher (p < 0.05) than in snake fruit (110.4 ( 7.9 and 1507.5 ( 70.1) and mangosteen (79.1 ( 5.9 and 1268.6 ( 62.3). HPLC/DAD analysis of durian (µg/100 g of FW) showed that quercetin (1214.23 ( 116.7) was present at levels three times that of caffeic acid, and twice as high as p-coumaric and cinnamic acids. The correlation coefficients between the bioactive compounds of fruits and their antioxidant activities were high (R 2 ) 0.99). Male Wistar rats (25) were divided into five dietary groups: the control group was fed the basal diet (BD); in addition to BD, the cholesterol (Chol) group was supplemented with 1% of Chol; the diets of the Chol/Durian, Chol/Snake, and Chol/Mangosteen groups were supplemanted with 5% of these fruits, respectively. It was found that diets supplemented with durian, and to a lesser degree with snake fruit and mangosteen, significantly hindered the rise in plasma lipids and the decrease in antioxidant activity. The nutritional values were comparably high. In conclusion, it could be suggested that inclusion of studied tropical fruits, especially durian, in known disease-preventing diets could be beneficial.
Intrinsic fluorescence (IF), surface hydrophobicity (S o ), electrophoresis, amino acid analysis,... more Intrinsic fluorescence (IF), surface hydrophobicity (S o ), electrophoresis, amino acid analysis, circular dichroism (CD), and differential scanning calorimetry (DSC) were used to study folded and unfolded soluble proteins from Amaranthus hypochondriacus (A. h.) and soybean (S). Globulin (Glo) and albumin subfractions (Alb-1 and Alb-2) were extracted from A. h. and S and denatured with urea. Electrophoretic and functional properties indicated a significant correlation between soluble protein fractions from soybean and amaranth. The protein fractions shared some common electrophoretic bands as well as a similar amino acid composition. The larger percent of denaturation in protein fractions, which is associated with enthalpy and the number of ruptured hydrogen bonds, corresponds to disappearance of R-helix. The obtained results provided evidence of differences in their secondary and tertiary structures. The most stable was Glo followed by the Alb-2 fraction. Predicted functional changes in model protein systems such as pseudocereals and legumes in response to processing conditions may be encountered in pharmaceutical and food industries. These plants can be a substitute for some cereals.
International Journal of Food Sciences and Nutrition, 2003
Amaranth, soybean and maize were screened for proteins and their nutritional value. Isopropanol-s... more Amaranth, soybean and maize were screened for proteins and their nutritional value. Isopropanol-soluble protein and buffer-soluble protein fractions were extracted from seeds and separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The comparison of the identity and differences between investigated plants was carried out by the obtained SDS-PAGE electrophoretic patterns, and their microstructure was determined by scanning electron microscopy. Electrophoretic patterns of extracted proteins have shown that the main protein subunits were concentrated between 10 and 50 kDa. Variations were found in major fractions and minor bands as well as in the fine structure. The microstructure of pseudocereal and cereal protein fractions was interrelated with the results obtained by their electrophoretic separation. Pseudocereal amaranth can be used as a nutritive substitute of cereal maize in functional foods.
International Journal of Food Sciences and Nutrition, 2009
The aim of this work was to determine the effect on consumer preference of dehydrated apple cubes... more The aim of this work was to determine the effect on consumer preference of dehydrated apple cubes caused by different modifications of a combined drying method. The combined process of convective-osmotic drying with pretreatment in solutions of CaCl(2) and citric acid was taken as the basic process, and was then modified to obtain six different treatments. The factors varied were the osmotic agent, the order of drying processes, and the addition of CaCl(2) to the osmotic solution. The drying kinetics of convective-osmotic treatment and the osmotic-convective process were studied. A sensory evaluation was conducted to determine the effect of these alterations in the drying process on the consumer preference for the product. The convective-osmotic treatment significantly reduced the time of processing. Water loss and solids gain were higher when fructose was used as the osmotic agent in the convective-osmotic process. According to the results of the preference test, only one of the modified processes showed significant preference compared with the basic process.
International Journal of Food Sciences and Nutrition, 2009
The aim of this investigation was to examine the influence of extrusion on the bioactive compound... more The aim of this investigation was to examine the influence of extrusion on the bioactive compounds and the antioxidant capacity of bean/corn mixtures. Whole bean flour and nixtamalized corn were mixed in a 60:40 proportion and extrusion was performed in different moisture (14.5%, 15.4%, 17.1% and 18.0%) and temperature (1508C, 1608C, 1708C, 1808C and 1908C) conditions in order to find the optimal extrusion conditions. According to their functional properties and antioxidant status, the mixtures 1428C/16.3% H, 1708C/16.3% H and 1988C/16.3% H were defined as optimal, moderate and bad, respectively. Total polyphenols and flavonoids in the mixture of 1428C/16.3% H (15.0991.7 mg gallic acid equivalent [GAE]/g dry weight [DW] and 1.5790.2 mg catechin equivalent [CE]/g DW) were significantly higher (P B0.05) than in the sample 1708C/16.3% H (9.4291.1 mg GAE/g DW and 1.490.1 mg CE/ g DW) and the mixture 1988C/16.3% H (6.4690.8 mg GAE/g DW and 0.7890.1 mg CE/g DW). The antioxidant activity (37.0293.8 and 25.0192.5 mM Trolox equivalent [TE]/g DW) of mixture 1428C/16.3% H, determined by the cupric reducing antioxidant capacity with Trolox equivalent antioxidant capacity and b-caroteneÁlinoleic acid (b-carotene,% of inhibition) assays, was significantly higher (P B0.05) than in 1708C/16.3% H (25.6992.8 and 17.0291.8 mM TE/ g DW) and in mixture 1988C/16.3% H (13.9391.5 and 8.9490.9 mM TE/g DW), respectively. The free polyphenols, flavonoids and the antioxidant activities showed lower results than the hydrolyzed ones. The correlation coefficients between polyphenols, flavonoids, and cupric reducing antioxidant capacity capacities were between 0.93 and 0.99. In cereal proteins extracted and separated by electrophoresis, some differences were found in the sodium dodecyl sulfateÁprotein bands in the region from 36 to 45 kDa for 1428C/16.3% H, in comparison with other samples. Therefore, there is a need to find such conditions for the extrusion procedures that would take into consideration the contents of the bioactive compounds and the antioxidant capacity in the end product.
Food associated diseases pose significant public health threat in the United States. Health risks... more Food associated diseases pose significant public health threat in the United States. Health risks associated with food-borne pathogens drive the need for constant monitoring of food products. An efficient method that can diagnose food-borne pathogens rapidly will be invaluable and in high demand. In this study, we showed the feasibility of a novel rapid detection platform based on fluorescence imaging/detection that combines a user-friendly, portable loop mediated isothermal amplification (LAMP) reaction device and a smartphone-based detection system. The proposed platform was used to detect Staphylococcus aureus which is one of the most important food-borne pathogen especially dairy products. The complete protocol is quicker; the reaction is performed under isothermal conditions and completed in 1 h or less. Experimental results show that LAMP assays were tenfold more sensitive than PCR-based detection. The proposed smartphone detection system was able to detect and quantify LAMP assay samples containing three different concentrations of S. aureus from 10 9 CFU/mL down to 10 3 CFU/mL. The present proof-of-concept study demonstrated that this platform offers a portable, easy to use method for measuring target pathogens with LAMP amplification. Food-borne pathogens are defined as biological agents that cause food-borne illness; they can be either viruses, bacteria and eukaryotes like funguses, protozoa or helminths 1. Every year, the Food and Drug Administration (FDA) reports the outbreaks associated with food-borne pathogens; for instance, in 2020, it reported the contamination of Escherichia coli, Listeria monocytogenes and Cyclospora in clover sprouts, Enoki mushrooms and bagged salad, respectively (FDA 2020). Health risks associated with food-borne pathogens drive the need for constant monitoring of food products. For microbial pathogen detection, the conventional method is bacterial growth on a culture medium then on selective agar; it sometimes involves biochemical or serological testing. This process has some disadvantages because it is time consuming, laborious and detection of non-culturable pathogens is not possible 2. By following the conventional methodology, the detection of E. coli O157 takes around 3 days, Salmonella 4-6 days and Vibrio parahaemolyticus around 7 days 3. For this reason, new techniques emerged which provide faster, more reliable and sensitive results; some of the most widely used are the polymerase chain
Jujube, commonly known as the Chinese date, is a nutritious fruit with medicinal importance. Fres... more Jujube, commonly known as the Chinese date, is a nutritious fruit with medicinal importance. Fresh jujube fruits have a shelf life of about ten days in ambient conditions that can be extended by drying. However, nutrition preservation varies with the drying method and parameters selected. We studied total phenolic content (TPC), proanthocyanidins (PA), vitamin C, cyclic adenosine monophosphate (cAMP), and antioxidant activities in jujube fruits dried with freeze-drying (FD), convective oven drying (OD) at 50 °C, 60 °C, and 75 °C, and sun drying (SD) with FD as a control. The cultivars used for this study were ‘Capri’ and ‘Xiang’ from Las Cruces in 2019, and ‘Sugarcane’, ‘Lang’, and ‘Sherwood’ from Las Cruces and Los Lunas, New Mexico, in 2020. Freeze-drying had the highest of all nutrient components tested, the best estimates of mature jujube fruits’ nutrient contents. Compared with FD, the majority of PA (96–99%) and vitamin C (90–93%) was lost during SD or OD processes. The retent...
Given consumer trends propelling a movement toward using plant protein in the food industry and s... more Given consumer trends propelling a movement toward using plant protein in the food industry and searching for alternative protein ingredients by the industry, this study aimed to assess the influence of factors such as protein concentration, medium pH, and the presence of a divalent ion (Ca2+) upon the rheological properties such as viscosity change and gel formation of dispersion proteins extracted from quinoa, black beans, and lentils. A solution of each protein was prepared by varying its concentration (2.5%, 5.0%, and 10%), the pH (5.0, 7.0, and 9.0), and the incorporation of calcium chloride (0.0% and 1.0%). Each obtained solution was subjected to rheological tests to determine the parameters: consistency index (K), flow behavior (n), the storage (G’) and loss (G’’) modules, and the phase shift angle (δ). The results demonstrate that the incorporation of Ca2+, the shift in protein levels, and the decrease in pH modified the rheological behaviors of proteins, which were also inf...
Muchos trabajos demuestran que los productos vegetales no solamente son fuentes de energía y nutr... more Muchos trabajos demuestran que los productos vegetales no solamente son fuentes de energía y nutrientes sino también fuentes de compuestos conocidos como fitoquímicos, que juegan un importante papel en la prevención de enfermedades como el cáncer, afecciones cardiovasculares y neurodegenerativas. Por otro lado, el aumento en la producción de manzana, determina también un aumento de la producción destinada al procesamiento industrial. En este sentido el conocer el contenido de de ciertas sustancias como polifenoles, antocianinas permiten conocer su potencial de uso industrial, como por ejemplo para la elaboración de jugos. En base a esto los objetivos del presente trabajo fueron realizar una caracterización físico-química de tres variedades de manzana; una de ellas de cultivo tradicional y muy extendido en Brasil y las otras dos mutaciones de esta última, de reciente explotación comercial. Fueron medidos al momento de cosecha la firmeza de la pulpa, acidez titulable (AT), los sólidos solubles totales (SST), el índice de yodo-almidón, los parámetros CIE "L*", "a*" y "b*" del color, polifenoles, antocianinas y azúcares reductores totales y vitamina C. Según los resultados, la variedad Fuji Kiku presentó una mayor firmeza de pulpa, AT, SST y vitamina C. En relación al color, la variedad Fuji Suprema mostró una coloración roja más intensa y mayor contenido de antocianinas. No fueron encontradas diferencias en los polifenoles y azúcares reductores totales. Palabras-clave: polifenoles totales; vitamina C; azúcares reductores; antocianinas; uso industrial.
The objective of this research was to evaluate the effect of the content of cottonseed meal (Goss... more The objective of this research was to evaluate the effect of the content of cottonseed meal (Gossypium hirsutum) and the processing variables on the functional properties and the content of gossypol of an extruded feed for sheep (Ovis aries). The diet was balanced according to the requirements of fattening Dorper sheep breed under 1 year. The extrusion process was optimized using a surface response methodology, with four independent variables: temperature in the last heating zone (120–160°C), moisture content (14–18%), screw speed (120 rpm–180 rpm), and cottonseed meal content (9 g–27 g 100 g−1), in a single screw extruder. The optimal food had 27.25% crude protein, 4.24% crude fat, 12.21% crude fiber, 46.95% nitrogen-free extract, and 9.35% ash. The composition of essential amino acids in the optimal diet was 1.00 g kg−1 of lysine, 1.25 g kg−1 of phenylalanine, 2.04 g kg−1 of leucine, 0.87 g kg−1 of isoleucine, 0.98 g kg−1 of threonine, 1.15 g kg−1 of valine, and 0.65 g kg−1 of his...
Gold fish (Carassius auratus) being an omnivorous fish was chosen as the candidate fish. Fingerli... more Gold fish (Carassius auratus) being an omnivorous fish was chosen as the candidate fish. Fingerling of C. auratus 2.34 gm after acclimated to laboratory condition for a period of 15 days were used in various studies. Five feeding types with 35% dietary protein level and with varying levels of algal meal were prepared and used. The fish were divided in to 5 groups. Group I was fed on Ulva reticulata free diet. Fish belonging to groups II, III, IV and V were fed on diets with 2, 4, 6 and 8% of Ulva reticulata supplementation respectively for 40 days. At the end of the experimental period growth, proximate composition, haematological parameters and carotenoid content were analyzed. It can be conclusively deduced from this study that Ulva reticulata had positively improved growth performance, haematological parameters and coloration in gold fish C. auratus. Reasons could be the high nutrient and mineral profile and carotene and chlorophyll a, b content of Ulva reticulata. This study suggests that U. reticulata can be included as an ingredient of gold fish diet up to 8%. Owing to the presence of disease resistance imparting antibacterial substances in the algae gold fish remained active and healthy and were free from bacterial infection, during the period of investigation. Antibacterial activity of U. reticulata on the tested fish pathogens indicates the scope of using extracts of U. reticulata an immuno-prophylactic for health management in the culture of Gold fish. Based on the results of this study, it was concluded that short term feeding had no adverse effect on gold fish but long term effect needs future research. Future work should focus on digestibility coefficients of different nutrient classes in U. reticulata prior to inclusion in formulated diets.
Several parameters, including particle size, solvent, temperature, and extraction method, affect ... more Several parameters, including particle size, solvent, temperature, and extraction method, affect phenolic compounds' extraction yield from a plant matrix. Considering the wide availability of sugarcane bagasse (SCB), this study analyzed the effect of different extraction methods and geographical origins on the yield, quality, and antimicrobial activity of phenolic compounds from SCB extracts. Samples from three geographical locations (Veracruz, Mexico; Santa Rosa, Texas, USA; and St. Mary, Louisiana, USA) were analyzed. Extraction was performed using an orbital shaker or ultrasonic bath at various times at a fixed temperature of 50°C, with 90% ethanol or methanol. The highest yield (5.91 mg GAE) was obtained using an orbital shaker for 24 h with 90% methanol as the solvent. HPLC-MS identified desferrioxamine b, baicalein, madecassic acid, and podototarin at different concentrations in all three SCB samples. The antimicrobial activity of these compounds was tested against Escheri...
ABSTRACT Agglutinating compounds are commonly used to improve the physical quality of aquafeeds. ... more ABSTRACT Agglutinating compounds are commonly used to improve the physical quality of aquafeeds. An evaluation was done of the effect of the agglutinating compound sodium alginate on the functional properties of aquaculture fish feed produced by extrusion. Meals containing one of four sodium alginate concentrations (0, 0.5, 1.5 and 2%) were extruded in a simple-screw extruder at 120 °C, 20% moisture content and a 1:1 compression ratio, extruding each treatment in duplicate. Expansion index values ranged from 1.11 to 1.12 with no differences (P &gt; 0.05) between the diets containing sodium alginate. In contrast, the different sodium alginate levels had positive (P &lt; 0.05) effects on water absorption index values (2.24 to 2.79 g/g), water solubility index values (10 to 12.94%), sinking velocity (6 to 8.56 cm/s) and hardness (1.98 to 3.31 N). Maximum hardness (3.31 N) was produced in the 2% sodium alginate diet. The highest sodium alginate level tested (2%) had the most appropriate physical and functional properties for an extruded fish meal-based (62%) aquaculture fish feed.
The ability for nitrate accumulation in potato tubers as affected by mineral fertilisation (N, K2... more The ability for nitrate accumulation in potato tubers as affected by mineral fertilisation (N, K20 and MgO), genotype and the site of cultivation was studied in a three-year-long field experiment. Fertilisation with potassium chloride and potassium sulphate increased nitrate concentration in the tubers while additional magnesium fertilisation reduced nitrate concentration. Significant differences in nitrate concentrations were observed in potato tubers depending on genetic conditions as well as on the cultivation location (with the same soil and climatic conditions, varieties and tillage). The nitrate content decreased as the result of storage at 4 ~ Concentration of these ions in tubers of table and industrial potatoes did not exceed Acceptable Daily Intake level determined by WHO.
Flor de Mayo M38, Pinto Villa and Bayo Victoria beans were stored under accelerated conditions fo... more Flor de Mayo M38, Pinto Villa and Bayo Victoria beans were stored under accelerated conditions for aging at 40 1C and 60% RH for 3 months. Following adjustment of moisture to 24, 26 and 28 g water/100 g solids, they were extruded at 165, 185 and 205 1C at a constant screw speed. Water absorption index (WAI) and bulk density of extrudates were measured. Feed humidity did not affect the evaluated properties. Storage conditions, temperature and cultivar were the parameters that influenced the evaluated properties. Higher value for WAI was obtained in aged beans, independently of cultivar, temperature and feed humidity used. The bulk density was similar for aged and not aged beans, but at the highest temperature it was lower for aged beans. This fact indicates that bean storing and interaction of temperature have important influence on the final quality of extrudates.
Extruded snacks were prepared from flour blends made with taro and nixtamalized (TF–NMF) or non-n... more Extruded snacks were prepared from flour blends made with taro and nixtamalized (TF–NMF) or non-nixtamalized maize (TF–MF) using a single-screw extruder. A central composite design was used to investigate the effects of taro flour proportion in formulations (0–100 g/100 g) and extrusion temperatures (140–180 °C) on the following indices: expansion (EI), water solubility (WSI), water absorption (WAI) and fat absorption (FAI). Moreover,
Journal of the Science of Food and Agriculture, 2002
Maize, wheat, amaranth, rice and soybean were screened for protein content. Alcoholsoluble (A1 an... more Maize, wheat, amaranth, rice and soybean were screened for protein content. Alcoholsoluble (A1 and A2) and glutelin (G1 and G2) fractions were isolated and compared in terms of their amino acid and protein compositions. The average proportions of nitrogen content between total alcohol-soluble proteins (TASP) and total glutelins (TGlu) in the pseudocereals amaranth and soybean were about 1.8:26.9 and 14.9:12.3 respectively. In the cereals maize and wheat these proportions were 47.8:33.2 and 44.7:31.2 respectively. The sum of essential amino acids was 47.6 and 60.3 g per 100 g protein in amaranth and soybean respectively. The highest contents of methionine, lysine and arginine were found in the pseudocereals. The relatively high content of essential amino acids shows that pseudocereals could be used as a nutrient substitute for cereals.
In vitro and in vivo studies of the health and nutritional properties of durian (Durio zibethinus... more In vitro and in vivo studies of the health and nutritional properties of durian (Durio zibethinus Murr.) were compared with snake fruit (Salacca edulis Reinw.) and mangosteen (Garcinia mangostana). Dietary fibers, minerals, and trace metals were comparable. Total polyphenols (mg of GAE/100 g of FW) and flavonoids (85.1 ( 6.1) were significantly higher (p < 0.05) than in snake fruit (217.1 ( 13.2 (mg of CE/100 g of FW)), durian (309.7 ( 19.3 and 61.2 ( 4.9), and mangosteen (190.3 ( 12.1 and 54.1 ( 3.8). Antioxidant activity (µM TE/100 g of FW) of durian measured by DPPH and ABTS assays (228.2 ( 13.4 and 2016.3 ( 81.1) was significantly higher (p < 0.05) than in snake fruit (110.4 ( 7.9 and 1507.5 ( 70.1) and mangosteen (79.1 ( 5.9 and 1268.6 ( 62.3). HPLC/DAD analysis of durian (µg/100 g of FW) showed that quercetin (1214.23 ( 116.7) was present at levels three times that of caffeic acid, and twice as high as p-coumaric and cinnamic acids. The correlation coefficients between the bioactive compounds of fruits and their antioxidant activities were high (R 2 ) 0.99). Male Wistar rats (25) were divided into five dietary groups: the control group was fed the basal diet (BD); in addition to BD, the cholesterol (Chol) group was supplemented with 1% of Chol; the diets of the Chol/Durian, Chol/Snake, and Chol/Mangosteen groups were supplemanted with 5% of these fruits, respectively. It was found that diets supplemented with durian, and to a lesser degree with snake fruit and mangosteen, significantly hindered the rise in plasma lipids and the decrease in antioxidant activity. The nutritional values were comparably high. In conclusion, it could be suggested that inclusion of studied tropical fruits, especially durian, in known disease-preventing diets could be beneficial.
Intrinsic fluorescence (IF), surface hydrophobicity (S o ), electrophoresis, amino acid analysis,... more Intrinsic fluorescence (IF), surface hydrophobicity (S o ), electrophoresis, amino acid analysis, circular dichroism (CD), and differential scanning calorimetry (DSC) were used to study folded and unfolded soluble proteins from Amaranthus hypochondriacus (A. h.) and soybean (S). Globulin (Glo) and albumin subfractions (Alb-1 and Alb-2) were extracted from A. h. and S and denatured with urea. Electrophoretic and functional properties indicated a significant correlation between soluble protein fractions from soybean and amaranth. The protein fractions shared some common electrophoretic bands as well as a similar amino acid composition. The larger percent of denaturation in protein fractions, which is associated with enthalpy and the number of ruptured hydrogen bonds, corresponds to disappearance of R-helix. The obtained results provided evidence of differences in their secondary and tertiary structures. The most stable was Glo followed by the Alb-2 fraction. Predicted functional changes in model protein systems such as pseudocereals and legumes in response to processing conditions may be encountered in pharmaceutical and food industries. These plants can be a substitute for some cereals.
International Journal of Food Sciences and Nutrition, 2003
Amaranth, soybean and maize were screened for proteins and their nutritional value. Isopropanol-s... more Amaranth, soybean and maize were screened for proteins and their nutritional value. Isopropanol-soluble protein and buffer-soluble protein fractions were extracted from seeds and separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The comparison of the identity and differences between investigated plants was carried out by the obtained SDS-PAGE electrophoretic patterns, and their microstructure was determined by scanning electron microscopy. Electrophoretic patterns of extracted proteins have shown that the main protein subunits were concentrated between 10 and 50 kDa. Variations were found in major fractions and minor bands as well as in the fine structure. The microstructure of pseudocereal and cereal protein fractions was interrelated with the results obtained by their electrophoretic separation. Pseudocereal amaranth can be used as a nutritive substitute of cereal maize in functional foods.
International Journal of Food Sciences and Nutrition, 2009
The aim of this work was to determine the effect on consumer preference of dehydrated apple cubes... more The aim of this work was to determine the effect on consumer preference of dehydrated apple cubes caused by different modifications of a combined drying method. The combined process of convective-osmotic drying with pretreatment in solutions of CaCl(2) and citric acid was taken as the basic process, and was then modified to obtain six different treatments. The factors varied were the osmotic agent, the order of drying processes, and the addition of CaCl(2) to the osmotic solution. The drying kinetics of convective-osmotic treatment and the osmotic-convective process were studied. A sensory evaluation was conducted to determine the effect of these alterations in the drying process on the consumer preference for the product. The convective-osmotic treatment significantly reduced the time of processing. Water loss and solids gain were higher when fructose was used as the osmotic agent in the convective-osmotic process. According to the results of the preference test, only one of the modified processes showed significant preference compared with the basic process.
International Journal of Food Sciences and Nutrition, 2009
The aim of this investigation was to examine the influence of extrusion on the bioactive compound... more The aim of this investigation was to examine the influence of extrusion on the bioactive compounds and the antioxidant capacity of bean/corn mixtures. Whole bean flour and nixtamalized corn were mixed in a 60:40 proportion and extrusion was performed in different moisture (14.5%, 15.4%, 17.1% and 18.0%) and temperature (1508C, 1608C, 1708C, 1808C and 1908C) conditions in order to find the optimal extrusion conditions. According to their functional properties and antioxidant status, the mixtures 1428C/16.3% H, 1708C/16.3% H and 1988C/16.3% H were defined as optimal, moderate and bad, respectively. Total polyphenols and flavonoids in the mixture of 1428C/16.3% H (15.0991.7 mg gallic acid equivalent [GAE]/g dry weight [DW] and 1.5790.2 mg catechin equivalent [CE]/g DW) were significantly higher (P B0.05) than in the sample 1708C/16.3% H (9.4291.1 mg GAE/g DW and 1.490.1 mg CE/ g DW) and the mixture 1988C/16.3% H (6.4690.8 mg GAE/g DW and 0.7890.1 mg CE/g DW). The antioxidant activity (37.0293.8 and 25.0192.5 mM Trolox equivalent [TE]/g DW) of mixture 1428C/16.3% H, determined by the cupric reducing antioxidant capacity with Trolox equivalent antioxidant capacity and b-caroteneÁlinoleic acid (b-carotene,% of inhibition) assays, was significantly higher (P B0.05) than in 1708C/16.3% H (25.6992.8 and 17.0291.8 mM TE/ g DW) and in mixture 1988C/16.3% H (13.9391.5 and 8.9490.9 mM TE/g DW), respectively. The free polyphenols, flavonoids and the antioxidant activities showed lower results than the hydrolyzed ones. The correlation coefficients between polyphenols, flavonoids, and cupric reducing antioxidant capacity capacities were between 0.93 and 0.99. In cereal proteins extracted and separated by electrophoresis, some differences were found in the sodium dodecyl sulfateÁprotein bands in the region from 36 to 45 kDa for 1428C/16.3% H, in comparison with other samples. Therefore, there is a need to find such conditions for the extrusion procedures that would take into consideration the contents of the bioactive compounds and the antioxidant capacity in the end product.
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Papers by Efren Delgado