Efecto de la ultra alta presión de homogeneización en licuado de soja y su comportamiento en el desarrollo de un producto fermentado

Consultable des del TDXDescripció del recurs: el 2 abril 2009Títol obtingut de la portada digitalitzadaEl objetivo general de esta tesis doctoral fue estudiar los efectos de la ultra alta presión de homogeneización (UHPH) en el licuado de soja, en comparación con tratamientos térmicos convencionales, y su aptitud para el desarrollo de un producto fermentado, tipo yogur de soja. Para alcanzar este objetivo general se plantearon los siguientes objetivos específicos: i) estudiar las características fisicoquímicas, microbiológicas, microestructurales de licuado de soja tratado por UHPH, así como los parámetros específicos de calidad indicativos de la eficacia del tratamiento, ii) estudiar el comportamiento a la coagulación ácida del licuado de soja tratado por UHPH y iii) estudiar la evolución durante el almacenamiento en refrigeración de los yogures de soja obtenidos a partir de licuados tratados por UHPH. La UHPH fue un tratamiento eficaz para disminuir la carga microbiana de los licuados de soja, y el efecto sobre la población inicial aumentó al incrementar la presión del tratamiento. En cuanto a las características fisicoquímicas, se encontró una importante reducción del tamaño de partícula, ligera disminución de la luminosidad, y mejora considerable de la estabilidad física. Las principales características químicas de calidad del licuado de soja revelaron que los tratamientos UHT y UHPH inactivan completamente la enzima LOX; además, mostraron una elevada digestibilidad, similar a los UHT. En el estudio de la coagulación ácida de los licuados de soja a 45ºC, el inicio de la coagulación se produjo más rápidamente en los licuados UHPH, y sus yogures de soja presentaron mayor firmeza, deformabilidad y capacidad de retención de agua que los elaborados a partir de los productos esterilizados y UHT almacenados en frío después de 24 horas de su elaboración. Asimismo, la evaluación sensorial avaló estas diferencias siendo los mayormente aceptados. Respecto al estudio del almacenamiento de los yogures de soja, los obtenidos a partir de los licuados de soja tratados por UHPH mostraron mayor carácter viscoelástico respecto a los obtenidos a partir del licuado de soja pasteurizado. El yogur de soja UHPH que presentó una menor diferencia de color respecto al de 95ºC 15 min, tomado como producto de referencia, fue el elaborado con licuado de soja tratado a 300 MPa 50ºC, 15 s. La fermentación y el almacenamiento de los sogures favorecieron la disminución de la actividad de los inhibidores de tripsina y apenas tuvieron efecto sobre los niveles de oxidación. Como conclusión final, se puede afirmar que la tecnología UHPH es muy adecuada para el tratamiento del licuado de soja y la obtención de yogur de soja, ya que da lugar a un producto con unas características de calidad, en general, mejoradas respecto del tratamiento término convencional. De los tratamientos estudiados el que dio lugar a mejores características globales fue el de 300 MPa.The general objective of this doctoral thesis was to study the effects of the ultra high pressure of homogenization (UHPH) in soymilk, in comparison with conventional heat treatments, and its aptitude for the development of a soy yoghurt-like fermented product. Specific objectives were: i) study the physicochemical, microbiological and microestructural characteristics of soymilk treated by UHPH, as well as the specific quality parameters indicative of the efficacy of the treatment, ii) study the behavior and properties during the acid coagulation of the UHPH treated soymilk and iii) study the evolution of soy yogurt obtained from UHPH treated soymilk during refrigeration storage. UHPH was an efficient processing to reduce total microbial counts, spores and enterobacteria, and the effect increased with the increase in the pressure of the processing. Regarding physicochemical characteristics, an intense reduction of particle size, diminution in lightness, high physical stability were evidenced in UHPH treated soymilks. The main chemical quality characteristics of the soymilk revealed that UHPH treatment completely inactivated the enzyme lipoxygenase; besides, UHPH soymilk showed high digestibility, similar to UHT soymilk. The study of the acid coagulation at 45ºC showed that the start of the coagulation was earlier in UHPH soymilk, and its soy yoghurts presented greater firmness, deformability and water-holding capacity than the elaborated from conventionally sterilized and UHT soymilks. UHPH soy yogurts were the most preferred during the sensory evaluation. Concerning to the study of the behaviour of soy yogurts during refrigerated storage, it was observed that yogurts from UHPH treated soymilk showed a greater viscoelastic character in comparison with yogurts from pasteurized soymilk. UHPH yoghurts elaborated with soymilk treated at 300 MPa 50ºC, 15 s presented the smallest difference in color compared with yogurt from soymilk treated at 95ºC 15 min, taken as a reference. The fermentation and the refrigerated storage of the soy yogurt favoured the decrease of the activity of trypsin inhibitor and barely had effect on the oxidation level. It can be concluded that UHPH technology is very adequate for the processing of soymilk and the obtention of soy yoghurt, since it gives rise to a product with characteristics of quality that, in general, are improved in comparison with the conventional heat treatment. The UHPH treatment that originated the best global characteristics in soy yogurt was 300 MPa

EFFECT OF LYOPHILIZED JUICE OF PUNICA GRANATUM L. IN ANTINOCICEPTIVE AND INFLAMMATORY PAIN

Objective: The aim of this study was to explore the analgesic activity of lyophilized juice of Punica granatum L., obtained from Hidalgo, Mexico, in theformalin test.Methods: We extracted the juice manually, filtered it and then dried down in a lyophilizer machine. We evaluated the antinociceptive effect oflyophilized juice from pomegranate in the formalin test (2%) in male Wistar rats (180–200 g body weight). Thirty minutes before the test, a dose of316 mg/kg (lyophilized juice) and acetylsalicylic acid as reference drug (100 mg/kg) both were administered intragastrically (i.g.).Results: The oral administration of lyophilized juice of pomegranate showed a significant decrease in the number of flinches in the temporal courseand a significant antinociceptive effect in nociceptive and inflammatory pain compared with the vehicle. In the same way, this effect appeared with thedrug of reference (acetylsalicylic acid 100 mg/kg i.g). Furthermore, it was shown that juice had a 34% of antinociception on overall effect versus vehicle.Conclusion: The results suggest that lyophilized juice of pomegranate has antinociceptive effect in nociceptive and inflammatory pain. Therefore, thisstudy supports the possible use of this lyophilized juice of pomegranate in the treatment of pain

INNOVACION DE PRODUCTOS DE ALTO VALOR AGREGADO A PARTIR DE LA TUNA MEXICANA

In the world, Mexico is the major producer of prickly pears and also has the largest number in varieties. However, in addition to its highly seasonal production, prickly pears are consumed just by a small segment of the Mexican population. Therefore, the promotion of prickly pears consumption in the form of new derivative products by emphasizing its bioactive properties seems to be a possible solution to its low consumption. Recent studies from European and Asian laboratories showed that some prickly pears varieties have a significant antioxidant activity. In Mexico, prickly pears producers are looking for new ways of commercialization. In this regard, similar studies are underway surveying those varieties from the highly producing Mexican states with the goal to develop new functional products with high added value. In addition, the use of prickly pears as a raw material for the cosmetic and pharmaceutical industries is being considered and seems to be highly promising.Prickly pears, antioxidant activity, innovation, functional food., Agribusiness,

Optimiranje postupka obrade nektara graviole (Annona muricata) toplinom i ultrazvukom, te usporedba fizikalno-kemijskih svojstava i biološke raspoloživosti antioksidansa in vitro optimiranog nektara s pasteriziranim uzorkom

Research background. Soursop nectar contains antioxidants and is preserved by pasteurization. However, this technology impairs its physicochemical properties and bioactive compounds. An alternative is therefore thermoultrasound, which could counteract these effects. The thermosonicated nectar was compared with a pasteurized one and the in vitro bioaccessibility of antioxidants was estimated. Experimental approach. The soursop nectar (25 %) was processed and the response surface methodology was used to determine the optimal conditions for thermoultrasound treatment (TUS). The TUS (75–90 % amplitude, 3.15–15 min) was applied, and 2 % stevia and 6 % agave inulin were added as sweeteners. The microbiological, physicochemical, enzymatic and antioxidant properties were analyzed. The properties of thermosonicated nectar obtained under optimal conditions were compared with pasteurized nectar. In addition to the above determinations, microstructure, total dietary fiber (TDF) and in vitro bioaccessibility of antioxidants were determined. Results and conclusions. The response variables that fit the mathematical model were L*, b*, chroma (C*), total phenolic content (TPC) and antioxidant activity determined by ABTS•+, DPPH˙ and Fe(III) reducing antioxidant power (FRAP). The L* and DPPH˙ were affected by quadratic time and TPC by time (p<0.0001). The optimum TUS condition was 82 % amplitude for 9.15 min and the responses variables were L*, b* and C* (45.48, 3.55 and 3.62, respectively), TPC expressed as gallic acid equivalents (38.40 mg/100 mL), ABTS•+ expressed as Trolox equivalents (TE) (31.28 μmol/100 mL), DPPH˙ expressed as TE (124.22 μmol/100 mL) and FRAP expressed as Fe(II) (3.06 μmol/100 mL). Compared to the pasteurized sample, thermosonicated sample had high values of L* (45.56), h° (-56.49), TPC (26.63 mg/100 mL), ABTS•+ and DPPH˙ (22.03 and 129.22 μmol/100 mL, respectively), FRAP (3.10 μmol/100 mL) and low pectin methylesterase (PME) activity (0.28 U/mL). For in vitro bioaccessibility, thermosonicated nectar showed high absorption of TPC (15.26/100 mL) and high antioxidant activity determined by ABTS (34.92 μmol/100 mL) and FRAP (7.88 μmol/100 mL). Novelty and scientific contribution. The thermoultrasound improves the physicochemical properties and in vitro bioaccessibility of antioxidants in soursop nectar. On the other hand, as an alternative, this beverage offers low-calorie alternative with prebiotic properties that benefits consumer health.Pozadina istraživanja. Nektar graviole sadržava antioksidanse, a radi produljenja roka trajanja tretira se pasterizacijom. Međutim, taj postupak narušava fizikalno-kemijska svojstva nektara i smanjuje količinu biološki aktivnih tvari u njemu. Stoga se kao alternativna metoda koristi kombinacija obrade toplinom i ultrazvukom. U radu smo usporedili svojstva nektara obrađenog toplinom i ultrazvukom s onima pasteriziranog uzorka te ispitali biološku raspoloživost antioksidansa in vitro. Eksperimentalni pristup. Obrađen je nektar graviole (s 25 % voćnog soka), a metodom odzivnih površina određeni su optimalni uvjeti obrade toplinom i ultrazvukom. Primijenjen je ultrazvuk amplitude 75-90 % tijekom 3,15–15 min, a kao zaslađivači su dodani 2 % stevije i 6 % inulina iz agave. Ispitana su mikrobiološka, fizikalno-kemijska, enzimska i antioksidacijska svojstva. Svojstva nektara dobivenog obradom toplinom i ultrazvukom pri optimalnim uvjetima uspoređena su s onima pasteriziranog uzorka. Osim toga, određeni su mikrostruktura, ukupna količina prehrambenih vlakana i in vitro biološka raspoloživost antioksidansa. Rezultati i zaključci. Varijable koje su odgovarale matematičkom modelu bile su L*, b*, zasićenost boje (C*), ukupni udjel fenola i antioksidacijska aktivnost određena metodama ABTS˙+, DPPH˙ i FRAP. Na vrijednost L* i sposobnost uklanjanja DPPH˙ utjecali su kvadratna vrijednost vremena te interakcija ukupnog udjela fenola i vremena (p<0,0001). Optimalni uvjeti obrade toplinom i ultrazvukom bili su amplituda 82 % tijekom 9,15 min, a odzivne varijable bile su L* (45,48), b* (3,55 ) i C* (3,62), ukupni udjel fenola izražen u ekvivalentima galne kiseline (38,40 mg/100 mL), sposobnost uklanjanja ABTS˙+ izražena u Trolox ekvivalentima (TE) (31,28 μmol/100 mL), sposobnost uklanjanja DPPH˙ izražena u TE (124,22 μmol/100 mL) i FRAP izražen kao Fe(II) (3,06 μmol/100 mL). U usporedbi s pasteriziranim uzorkom, dobiveni je nektar imao velike vrijednosti L* (45,56), h° (–56,49), ukupnog udjela fenola (26,63 mg/100 mL), dobru sposobnost uklanjanja ABTS˙+ (22,03 μmol/100 mL) i DPPH˙ (129,22 μmol/100 mL), veliku vrijednost FRAP (3,10 μmol/100 mL), a malu aktivnost metil esteraze (0,28 U/mL). Ispitivanje in vitro bioraspoloživosti antioksidansa pokazalo je da dobiveni nektar ima veliku biorapoloživost ukupnog udjela fenola (15,26/100 mL) i izraženu antioksidacijsku aktivnost, određenu pomoću ABTS (34,92 μmol/100 mL) i FRAP (7.88 μmol/100 mL) metoda. Novina i znanstveni doprinos. Obradom toplinom i ultrazvukom poboljšana su fizikalno-kemijska svojstva i in vitro biološka raspoloživost antioksidansa iz nektara graviole. Dobiveni napitak može poslužiti kao niskokalorična alternativa s prebiotičkim svojstvima i pozitivnim učinkom na zdravlje korisnika

Betalain, Acid Ascorbic, Phenolic Contents and Antioxidant Properties of Purple, Red, Yellow and White Cactus Pears

Commercialization of cactus pears based on their antioxidant properties can generate competitive advantages, and these can turn into business opportunities and the development of new products and a high-value ingredient for the food industry. This work evaluated the antioxidant activities (1,1-diphenyl-2-picrylhydrazyl radical-scavenging, protection against oxidation of a β-carotene-linoleic acid emulsion, and iron (II) chelation), the content of total phenolic compounds, ascorbic acid, betacyanin, betaxanthin and the stability of betacyanin pigments in presence of Cu (II)-dependent hydroxyl radicals (OH•), in 18 cultivars of purple, red, yellow and white cactus pear from six Mexican states. Our results indicated that the antiradical activities from yellow and white cactus pear cultivars were not significantly different (p < 0.05) and were lower than the average antiradical activities in red and purple cultivars. The red cactus pear from the state of Zacatecas showed the highest antioxidant activity. The free radical scavenging activity for red cactus pears was significantly correlated (p < 0.05) to the concentration of total phenolic compounds (R2 = 0.90) and ascorbic acid (R2 = 0.86). All 18 cultivars of cactus pears studied showed significant chelating activity of ferrous ions. The red and purple cactus pears showed a great stability when exposed to OH•

Ultrasound with controlled temperature as an emerging technology for extraction of antioxidant compounds from by-products of mango (Mangifera indica L. var Ataulfo) juice

During the industrial processing of juice high amounts of by-products are obtained which are discarded. The objective of this study wasto optimize the conditions of ultrasound process using response surface methodology (RMS) based on antioxidant compounds extraction(total phenolic content (TPC) and ascorbic acid (AA) and antioxidant activity (ABTS and DPPH) of mango waste and its comparison withtwo conventional extraction methods (aqueous and hydroalcoholic). All response variables were fitted to the mathematical model (R2 ≥ 95).The optimal processing conditions corresponded to 91% of amplitude with a treatment time of 7 min, reaching the highest extraction ofTPC and AA, as well as antioxidant activity. And in comparison, to conventional extraction methods (aqueous and hydroalcoholic), theoptimal ultrasound conditions had (p< 0.05) highest antioxidant content with 8800 mg GAE/100 g dry weight (dw) to total phenoliccontent, 5600 mg AAE/100 g dw in ascorbic acid, 60000 and 7500 µmol TE/100 g dw for DPPH• and ABTS•+ assays, respectively.These results demonstrate that ultrasound is an alternative method to enhance the extraction of antioxidants from mango industrial wastewhich could be used as additives in food products.Keywords: Anti-radical activity, Mango (Mangifera indica L.), Response Surface Methodology, Tropical fruit

Effect of Thermoultrasound on the Antioxidant Compounds and Fatty Acid Profile of Blackberry (Rubus fruticosus spp.) Juice

Blackberry (Rubus fruticosus spp.) fruit has high antioxidant activity due to its significant content of anthocyanins and antioxidant compounds. Among emerging technologies for food preservation, thermoultrasound is a technique that reduces microbial loads and releases compounds with antioxidant properties. The objective of this study was to determine the antioxidant content and fatty acid profile of blackberry juice subjected to thermoultrasound treatment in comparison to pasteurized juice. Blackberry juice and n-hexane extracts from a control (untreated juice), pasteurized, and thermoultrasonicated samples were evaluated for antioxidant activity, fatty acid profile, and antioxidant content. The juice treated with thermoultrasound exhibited significantly (p &lt; 0.05) higher levels of total phenols (1011 mg GAE/L), anthocyanins (118 mg Cy-3-GlE/L); antioxidant activity by ABTS (44 mg VCEAC/L) and DPPH (2665 µmol TE/L) in comparison to the control and pasteurized samples. Oil extract from thermoultrasound juice also had the highest antioxidant activity (177.5 mg VCEAC/L and 1802.6 µmol TE/L). The fatty acid profile of the n-hexane extracts showed the presence of myristic, linolenic, stearic, oleic, and linoleic acids and was not affected by the treatments except for stearic acid, whose amount was particularly higher in the control. Our results demonstrated that thermoultrasound can be an alternative technology to pasteurization that maintains and releases antioxidant compounds and preserves the fatty acids of fruit juice

Ultrasound with controlled temperature as an emerging technology for extraction of antioxidant compounds from by-products of mango (Mangifera indica L. var Ataulfo) juice

During the industrial processing of juice high amounts of by-products are obtained which are discarded. The objective of this study wasto optimize the conditions of ultrasound process using response surface methodology (RMS) based on antioxidant compounds extraction(total phenolic content (TPC) and ascorbic acid (AA) and antioxidant activity (ABTS and DPPH) of mango waste and its comparison withtwo conventional extraction methods (aqueous and hydroalcoholic). All response variables were fitted to the mathematical model (R2 ≥ 95).The optimal processing conditions corresponded to 91% of amplitude with a treatment time of 7 min, reaching the highest extraction ofTPC and AA, as well as antioxidant activity. And in comparison, to conventional extraction methods (aqueous and hydroalcoholic), theoptimal ultrasound conditions had (p< 0.05) highest antioxidant content with 8800 mg GAE/100 g dry weight (dw) to total phenoliccontent, 5600 mg AAE/100 g dw in ascorbic acid, 60000 and 7500 µmol TE/100 g dw for DPPH• and ABTS•+ assays, respectively.These results demonstrate that ultrasound is an alternative method to enhance the extraction of antioxidants from mango industrial wastewhich could be used as additives in food products.Keywords: Anti-radical activity, Mango (Mangifera indica L.), Response Surface Methodology, Tropical fruit

Innovación de productos de alto valor agregado a partir de la tuna mexicana

In the world, Mexico is the major producer of prickly pears and also has the largest number in varieties. However, in addition to its highly seasonal production, prickly pears are consumed just by a small segment of the Mexican population. Therefore, the promotion of prickly pears consumption in the form of new derivative products by emphasizing its bioactive properties seems to be a possible solution to its low consumption. Recent studies from European and Asian laboratories showed that some prickly pears varieties have a significant antioxidant activity. In Mexico, prickly pears producers are looking for new ways of commercialization. In this regard, similar studies are underway surveying those varieties from the highly producing Mexican states with the goal to develop new functional products with high added value. In addition, the use of prickly pears as a raw material for the cosmetic and pharmaceutical industries is being considered and seems to be highly promising.México es el primer productor de tuna a nivel mundial y posee diversas variedades de este fruto. Sin embargo, su consumo esta limitado a un determinado segmento de la población y es estacional, lo que desincentiva el aumento de su producción. Una posible solución es la promoción del consumo de tuna por sus propiedades bioactivas en forma de productos de alto valor agregado. Estudios recientes realizados en Europa y Asia han reportado que algunas variedades de tuna de esas regiones presentan una importante actividad antioxidante. En México, se llevan a cabo estudios sobre la actividad antioxidante de las variedades de tuna que se producen en diversos estados con la finalidad de producir alimentos funcionales con un alto valor agregado; con ello se busca diversificar su comercialización e incrementar su producción. Existe además un uso potencial de la tuna como materia prima en otros ramos industriales como la cosmética y farmacéutica