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Total phenolic content (TPC), total flavonoid content (TFC), antioxidant and antimicrobial in vitro activity of ethanolic (EE) and hydroethanolic (HE) extracts of mango peel Ataulfo were evaluated. The highest TPC, TFC and antioxidant capacity were as shown in EE. Ethanolic extract was incorporated into ground beef at 1000 (BBEA) and 2000 mg/kg meat (BEEB) concentrations and then compared with 250 mg of sodium ascorbate/kg meat (ASC) along with a control (without antioxidant). The effects of adding EE on instrumental colour, metmyoglobin content, thiobarbituric acid reactive substances (TBARS), pH, microbial load and sensorial analysis of ground beef were evaluated for 11 days at 4 °C. BEEB added in raw ground beef improved colour stability while the lipid oxidation in raw and raw-cooked ground beef was inhibited with a greater antioxidant effect than ASC and a similar overall acceptability score (cooked ground beef). However, incorporating BEEB into ground beef did not show significant antimicrobial activity. Therefore, mango peel extracts could potentially be used as a natural antioxidant in ground beef.

Ruta graveolens es una maleza que se puede utilizar como alimento de conejos. El objetivo de este estudio fue determinar la tasa de crecimiento, la calidad de la canal y de la carne de conejos despues de la suplementacion dietetica con Ruta graveolens . En total, 60 conejos destetados fueron asignados aleatoriamente a cinco tratamientos: dieta control (C), dieta adicionada con hojas (25RL o 50RL) o la planta completa de Ruta graveolens (25CP o 50CP). Con el uso de Ruta graveolens se observo tasas de crecimiento y de conversion alimenticia similares al grupo control ( P >0.05). La calidad de la canal difirio ( P

The objective of this study was to characterize the substrates after their degradation by P. ostreatus within 60 days of cultivation in four Mexican mushroom-producing companies, in order to use it as a complement feed for ruminants. The acid detergent fiber (ADF), neutral detergent fiber (NDF), protein fraction, and mineral profile were analyzed after degradation. Crude protein (CP) of companies 1 and 4 increased by 6.1% and 6.8%, respectively (p ≤ 0.05). Soluble nitrogen reached 60% relative to un-degraded substrate with 43.8%. Proteins A, B1, and B3 fractions increased compared to controls (p ≤ 0.05) at some companies. The B2 fraction was decreased in all the degraded substrates (p ≤ 0.05), but the C fraction at companies 1, 2, and 3 presented no significant differences with respect to their controls (p ≤ 0.05). Crude fiber (CF), ADF, NDF, and hemicellulose (HC) decreased while dry matter digestibility (DMD) increased to 55.5-58% on degrade substrates. The mineral composition increased disproportionately. The substrate degraded by P. ostreatus by improving its digestibility and soluble protein content may be a low-cost food supplement. However, due to its mineral imbalance, it is not recommended as the sole food source for ruminants.

El objetivo del trabajo es proponer el insecto Tenebrio molitor como alternativa nutricional e informar sobre los métodos de producción de este, ya que no solo tienen las características nutricionales necesarias para una buena dieta por su alto contenido nutricional, sino que también tienen una variedad de cualidades benéficas para la salud de los consumidores. Es bien sabido que México es un país con problemas nutricionales, debido principalmente a la falta de conocimientos sobre opciones nutricionales y a las deficiencias que las personas tienen en su dieta; por lo que una alternativa a esta problemática es ampliar el conocimiento y opciones alimenticias. El Tenebrio molitor es conocido como una opción nutricional por la gran cantidad de proteínas que contiene, lo que proporcionan una opción nutricional, además de los beneficios para la salud que pueden tener gracias a la presencia de péptidos bioactivos. No se sabe mucho sobre el manejo que estos insectos deben tener para evitar plagas o infecciones durante su producción, además de los cuidados específicos necesarios para una producción rápida y sostenible.

Los microorganismos causantes de enfermedades en el humano y animales están en constante evolución, por lo que es de vital importancia encontrar alternativas para su tratamiento y prevención. La resistencia antimicrobiana, definida por la OMS como la capacidad que tienen los microorganismos de impedir que los antimicrobianos actúen contra ellos, es un problema creciente en nuestra sociedad. En el año 2016, la Organización Mundial de la Salud publicó un informe en el que se estimó que para ese año se atribuían 700 000 muertes a la resistencia a antimicrobianos en el mundo, y que la cifra puede ascender hasta 10 millones de muertes en los próximos 35 años si no se toman medidas adecuadas. Para el siguiente año, la OMS publicó un reporte donde se mencionan 51 nuevos antimicrobianos que pueden ser una alternativa al tratamiento de algunas enfermedades, sin embargo, solo 8 de estas moléculas se consideran con potencial terapéutico. El uso de insectos en la medicina no es considerada una práctica reciente, ya que hay referencias de ella desde las primeras civilizaciones y ha sido demostrado que tiene aspectos benéficos no solo para la nutrición, sino para ámbitos de salud. Por ejemplo, los péptidos antimicrobianos se han descrito en muchas especies de organismos: hongos, plantas, humanos e insectos, siendo estos últimos en los que más se han descrito péptidos antimicrobianos eficaces.

La carne de conejo es susceptible a la oxidación y crecimiento de microorganismos, ya que posee ácidos grasos insaturados y un contenido nutricional que la hace idónea a esos procesos. La búsqueda de opciones naturales para disminuir las cargas microbianas y la oxidación es constante, por ello aquí se presenta como una alternativa la utilización de Dalbergia palo-escrito como una alternativa que contribuya a mejorar la calidad de la carne de conejo.

El lactosuero es un subproducto de la industria láctea, el cual posee un alto valor nutritivo por la presencia de proteínas, lactosa, vitaminas y minerales que tienen funciones biológicas de interés. El lactosuero puede ser utilizado directamente como ingrediente en diversos productos o puede ser fraccionado en sus diferentes componentes, para utilizarlos con diversos objetivos, dando así un valor agregado a este subproducto, sin embargo la falta de información acerca de su aprovechamiento ha generado que productores terminen por desecharlo perdiendo con ello valiosos componentes nutritivos. Por lo cual la presente investigación ofrece una breve revisión de los usos y propiedades del lactosuero.

El calostro bovino es conocido como la primera secreción que producen los mamíferos después del parto y se diferencia de la leche madura debido a su alto contenido proteico por la presencia de inmunoglobulinas, lactoferrina, lactoperoxidasa y lisozima además de ser rico en vitaminas y minerales, por lo cual se ha usado en la alimentación humana como suplemento o elaborando alimentos a base calostro, mostrando una mejoría en el sistema gastrointestinal, respiratorio e inmune.

La creciente preocupación por el uso de desechos agroindustriales ha generado la búsqueda de procesos de transformación y reutilización de estos. Los cuales son poco explotados, debido a que se desconocen su composición química y posibles transformaciones. En la industria del cacao, la cáscara de vaina de cacao es desechada en los cultivos, donde se descompone, propagando el hongo Phytophora spp que contamina la plantación sana, causando pérdidas a los productores, así como problemas ambientales. Por lo que el siguiente estudio de investigación tiene como objetivo determinar las características morfométricas, el análisis químico proximal y la capacidad antioxidante en la harina de cáscara de la vaina de cacao, para evaluar su viabilidad como materia prima. Determinando el rendimiento, análisis químico proximal, fenoles. Obteniendo un porcentaje de rendimiento del 29%, morfologicamente alcanza una altura máxima de 36nm. El análisis químico proximal mostró un porcentaje de fibra cruda de 26.75%, ceniza 8.41%, humedad 6.26%, proteína 5.27% y grasa 0.69%. Reportando un contenido de compuestos fenólicos de 8,48 mg de ácido gálico / g muestra seca. Concluyendo que la harina de cáscara de vaina de cacao, aporta cenizas y fibra, además de mostrar capacidad antioxidante, lo que la convierte en una materia prima con interés agroindustrial.

El estilo de vida actual puede promover hábitos alimenticios inadecuados, causando problemas de salud. El síndrome metabólico se considera una forma importante de riesgo cardiovascular y diabetes. La Oxalis, es un tubérculo andino, con una alta concentración de carbohidratos, aminoácidos esenciales, fibra, minerales y antioxidantes naturales como ácidos fenólicos, flavonas y antocianinas. El objetivo de este estudio fue evaluar las propiedades nutricionales de una pasta enriquecida con harina de Oxalis tuberosa y su efecto sobre maracdores bioquimico y antropometricos inducido en ratas wistar. Los fenoles totales y la actividad antioxidante fueron mayores en la pasta con Oxalis, así como en proteína y fibra. El grupo inducción alimentado con la pasta Oxalis mostró menor concentración en glucosa, colesterol y triglicéridos en comparación a los otros grupos. Estos datos sugieren que la pasta de Oxalis tuberosa puede ayudar a reducir el daño patológico del síndrome metabólico in vivo.

La utilización de carne de conejo en productos procesados es baja. Sin embargo, el chorizo elaborado con carne de conejo puede ser una opción para incrementar el mercado de este tipo de carne. El objetivo de este estudio fue determinar el efecto de mezclar proteína de soya texturizada y carne de conejo sobre el perfil de textura y propiedades sensoriales de chorizo. Se utilizaron cinco tratamientos, un control y cuatro con mezclas de carne de conejo y soya texturizada en proporciones de 10, 20, 30 y 40%. Se midió actividad de agua, análisis de perfil de textura, color y se llevó a cabo una prueba sensorial al final del experimento de cuatro de los tratamientos. Los resultados indican que la Aw y pH disminuyeron (p0.05), pero en color, dureza y sabor fueron diferentes (p

Some physicochemical characteristics and antioxidant activity of extrudates made from corn grits and red potato flour were evaluated. The inclusion of red potato flour altered values of water absorption index, water solubility index, expansion index and fracturability of extrudates. Color analysis of extrudates showed a reduction of luminosity from 44.37 ± 0.87 to 25.06 ± 1.74. Likewise, extrudates made with red potato flour at 100% presented higher content of total phenols compared to the control extrudates (0.44 ± 0.02 and 2.88 ± 0.03 mg GA/g dry sample, respectively); consequently, an increase in antioxidant capacity was observed using DPPH, ABTS and FRAP assays. The images obtained by fluorescence microscopy provided information on the protein content. The proximal chemical analysis indicated that extrudates substituted with red potato flour at 10% showed higher protein content (7.78 g/100 g), compared to T5. This study concludes that when adding red potato flour, is possible to develop extrudates with good physicochemical characteristics and antioxidant properties.

Nowadays, the uncontrolled use of antibiotics has created the problem of bacterial resistance to them, what has motivated the search for new alternatives of drug for the treatment of bacterial diseases. Here, we compare antimicrobial activity of spent substrate of mushroom Pleurotus ostreatus combined or not with medicinal plants and Lentinula edodes, against Escherichia coli, Staphylococcus epidermidis, Bacillus subtilis, Salmonella tiphymorium, Staphylococcus aureus and Micrococcus luteus. We designed three mixtures, barley straw to be used as a substrate of cultivation of mushroom Pleurotus ostreatus and oats or cedar for the cultivation of mushroom Lentinula edodes and five mixtures with herbs (barley straw/Chenopodium ambrosioides L., barley straw/Mentha piperita L., barley straw/Rosmarinus officinalis L., barley straw/Litsea glaucescens Kunth and barley straw/Tagetes lucid Cav) to be used as a substrate of cultivation of mushroom Pleurotus ostreatus; were obtained aqueous extracts from all spent substrates; extracts were tested for antibacterial activity. The protocol was a completely randomized assay with a factorial arrangement design. The data were analyzed with PROC GLM, SAS. The results showed that in the case of Escherichia coli the greatest inhibition zone was of 12.66 mm at a concentration of 6 mg mL-1, with treatment of Lentinula edodes/cedar; Salmonella tiphymorium showed a greatest inhibition zone of 31.10 mm to a concentration of 5.12 mg mL-1, with treatment of Pleurotus ostreatus/barley straw; Staphylococcus aureus showed a greatest inhibition zone of 9.33 mm to a concentration of 100 mg mL-1, with the treatment of Lentinula edodes/cedar; Micrococcus luteus showed a greatest inhibition zone of 15.00 mm to a concentration of 50 mg mL-1, with the treatment Lentinula edodes/oats and finaly, Staphylococcus epidermidis showed a greatest inhibition zone of 33.33 mm at a concentration of 50 mg mL-1, and 40.00 mm at a concentration of 50 mg mL-1, with treatment the spent substrate from Pleurotus ostreatus that contained barley straw and the mix barley straw/Mentha piperita L, respectively. In conclusion, the results suggest that it is possible to use indistinctly the spent substrate of Pleurotus ostreatus and Lentinula edodes, as well as the mix barley straw/Mentha piperita L as source of extracts with antibacterial activity.

BAMLET is a bioactive complex formed by the interaction between α-Lactoalbumin (α-LA) and oleic acid which exhibits cytotoxic activity against cancer cells. BAMLET is selectively cytotoxic to malignant cells while sparing the healthy ones. There are, however, no reports about its application in a food matrix. The objective of this work was to synthetize the BAMLET complex from oleic acid and bovine colostrum from the second and third milkings which naturally contain α-LA to prepare two functional spreadable cheeses. The complex was successfully formed and retained in the cheeses as verified through SDS-PAGE applied to the whey obtained. The spreadable cheese from the second milking had a higher protein content (13.56 ± 0.02%) and a higher yield (40%) than the product obtained from the third milking. Even though the cheeses did not show any significant differences (p > 0.05) in the inhibition of the angiotensin-converting enzyme 1, their inhibitory activities were good, as a 0.5 g portion of the cheese from the second milking was sufficient to inhibit 57.52 ± 9.17%, while the cheese from the third milking inhibited 51.48 ± 1.07% of the enzyme. The sensory analysis showed a good acceptance for both spreadable cheeses.

The quality and physicochemical properties of dough and noodles made from blends of chayotextle flour and wheat semolina were investigated. The results showed that the inclusion of chayotextle flour increased both the hardness and adhesiveness of the dough, and there was a 10% increase in cohesiveness and elasticity when using this particular flour. Regarding dough extensibility, no significant differences were found (p < 0.05) in the control, while the proximal chemical analysis on dough showed that T1 (16.28%) had a higher protein content compared to the control. These results indicate that the optimum mixture for the preparation of dough was obtained by using 10% chayotextle flour. It is concluded that incorporating appropriate amounts of this flour into wheat semolina during the production of dough maintains technological quality as well as texture and sensory perceptions.

The objective of this study was to use different parts of the Tithonia tubaeformis plant in feed for fattening rabbits and then observe the effects on carcass and meat quality. Forty-eight weaned rabbits (35 days of age) were randomly assigned to four groups (n = 12 by treatment). Animals were fed ad libitum a control diet as well as three experimental diets, with addition of Tithonia tubaeformis leaves, whole plant, and stems. Rabbits were slaughtered after 63 days of age without fasting. Results indicate that live weight (0.917), skin (0.79), feet (6.679), and lumbar circumference of the carcass (0.707) have higher positive correlations with hot carcass. There were no significant differences between treatments for all variables measured, except for kidneys and kidney fat. pH and color values were different among treatments. The results indicate that Tithonia tubaeformis leaves or the whole plant could be added to feed for growing rabbits.

El consumo de insectos alrededor del mundo es cada vez más aceptado en diferentes culturas, debido a que son de fácil cultivo, se reproducen sencillamente y no requieren de mucho mantenimiento, por lo que se están proponiendo como una fuente alternativa y viable de aporte nutricional, no solo para consumo de mascotas sino también para consumo humano, además de este gran beneficio nutricional, los insectos son utilizados como tratamientos alternativos en la medicina tradicional, para curar o prevenir algunas enfermedades, entre ellas el cáncer

Goat milk composition can be influenced by diet, such as adding exogenous enzymes into the feed to improve digestibility. The objective of this study was to evaluate milk composition and cheese goat yield when ruminants consumed an enzymatic extract obtained from spent Pleurotus ostreatus substrate. A one-way experimental design was used in this study. Enzymatic activity and milk composition were measured (fat, lactose, minerals, protein, total solids and non-fatty solids) while fresh cheese yield and their traits, such as color and texture, were also were determined. The enzymatic extract presented xylanase, laccases and cellulases activity (32227.72, 2822.33 and 69.03 IU MS g−1, respectively). Results indicate that the enzymatic extract increased the cheese yield (P

Tithonia tubaeformis se ha estudiado poco en general, hasta donde se tiene conocimiento no se ha empleado en la alimentacion de conejos. Es por ello con el objetivo de este estudio utilizar diferentes partes de la planta de Tithonia tubaeformis en la alimentacion de conejos con la finalidad de observar el efecto sobre los parametros productivos en animales de engorda. Se utilizaron 48 conejos de las razas Nueva Zelanda, California y Mariposa, distribuidos en 4 tratamientos. Se midieron parametros productivos durante la engorda, tambien se realizaron mediciones morfometricas y de rendimiento de la canal. Los resultados indican que no existen diferencias significativas (P>0.05) de todas las variables medidas, pero existe una tendencia a mejorar los parametros productivos de los conejos al incluir en su dieta hojas de Tithonia tubaeformis. Por ello se concluye que esta planta puede ser empleada en la alimentacion de conejos de engorda sin presentar efectos productivos adversos.

El presente trabajo se realizo con la finalidad de determinar el efecto de la inclusion de manzanilla y ruda en el alimento de conejos de engorda sobre la calidad de la canal y de la carne. Para ello se emplearon 24 conejos al destete y se engordaron por cuatro semanas hasta alcanzar un promedio de 63 d de edad. Los conejos fueron sacrificados y se evaluo la calidad de la canal y de la carne, para ello se tomaron medidas morfometricas, ademas de realizar la diseccion de la canal. Los resultados indican diferencias significativas (P

This study investigates the effect on performance, carcass and meat characteristics of increasing the forage level in the diet of fattening Tudanca young bulls using silage as the forage source as compared with a conventional ad libitum straw plus concentrate diet. Twenty two Tudanca young bulls were assigned to three different finishing diets: ad libitum grass silage plus ad libitum concentrate (GS-AC), ad libitum grass silage plus concentrate limited to a half of the intake of the ad libitum group (GS-LC), ad libitum barley straw plus ad libitum concentrate (Str-AC) and then slaughtered at around 11 months of age. GS-LC diet resulted in relation to GS-AC and Str-AC diets in lower (p

Rabbit breeding is an activity that is growing worldwide due to its easy handling, high reproduction rate and the possibility of generating profits from the sale of animals or the benefit of animal protein through self-consumption. The high feed costs in the production of rabbits through the use of commercial food, make that are looked for alternatives of feeding for this species, as it can be the "palo escrito" plant (Dalbergia palo-escrito sp). The leaves of this plant contain high amounts of protein, it is perhaps for this reason that this gender is part of their diet. The effect of replacing the proportion of alfalfa per "palo escrito" in the diet of rabbits for fattening on the quality of the carcass and the meat of rabbits was evaluated. The results showed that the use of "palo escrito" in the diet of rabbits is totally harmful, since, in the first week of treatment, all the animals died, even though some beneficial effect has been reported in some other animals. Regarding the use of alfalfa or maize in multinutritional diets, the rabbits treated with maize showed a significant difference in the productive parameters and in the quality of the channel with respect to those treated with alfalfa. It is necessary to continue studying the "palo escrito" because possibly its secondary metabolites may have the beneficial effect if they are included as additives. Palabras clave: Meat quality, rabbit production, Dalbergia palo-escrito.

La cunicultura es una actividad que esta creciendo a nivel mundial en los ultimos tiempos, debido a su facil manejo, la rapidez con la que se reproducen y la posibilidad de generar animales para su venta o autoconsumo. El mantener un sistema digestivo del conejo bajo condiciones apropiadas de pH, hace que el alimento consumido se pueda digerir mejor y los nutrientes esten disponibles para su absorcion, ademas de que el pH puede ser un factor desencadenante que propicie el crecimiento de microorganismos que puedan afectar la salud del conejo. Aqui evaluamos la calidad de la canal y de la carne de conejo, en animales tratados con vinagre y agua fermentada en agua de bebida, con la finalidad de mejorar el funcionamiento del sistema digestivo, para obtener mejores caracteristicas de la calidad de la canal y de la carne. Los resultados encontrados mostraron que no existen diferencias significativas si se utiliza vinagre o agua fermentada en la calidad de carne y de la canal en conejos, solo se observo diferencia significativa en el color, en el valor de L (P

La cunicultura es una actividad que esta creciendo a nivel mundial en los ultimos tiempos, debido a su facil manejo, la rapidez con la que se reproducen y la posibilidad de generar animales para su venta o autoconsumo. Uno de los principales problemas a los que se enfrenta esta actividad, es que no hay opciones farmacologicas para el tratamiento de enfermedades en dichos animales, por tal motivo, se han buscado estrategias alternativas para proteger y/o prevenir contra estas enfermedades, una de las opciones es el uso de plantas medicinales. Aqui evaluamos el efecto de la utilizacion de infusion de epazote en la engorda de conejos, sobre la produccion animal y rendimiento de la canal. Los resultados encontrados mostraron que el uso de 10 g de epazote administrados como infusion en la engorda de conejos, aumento los parametros productivos y permitio que no hubiera mortalidad durante las 4 semanas de tratamiento, por lo que seria importante evaluar su efecto sobre la calidad de la carne y los productos carnicos derivados de la misma. Palabras clave: produccion de conejo, rendimiento de la canal, Chenopodium ambrosioides

La utilizacion de enzimas fibroliticas exogenas comerciales (celulasas y xilanasas) ha sido ampliamente empleada en produccion animal, con la finalidad de complementar la actividad de las enzimas endogenas, para lograr un incremento en la respuesta de produccion de leche. En esta investigacion se pretende utilizar como alternativa el uso de enzimas exogenas obtenidas del sustrato gastado de Pleurotus ostreatus con el fin de evaluar los parametros productivos de cabras. Los resultados mostraron que la inclusion en la dieta de este extracto enzimatico, tuvo efecto sobre la ganancia diaria de peso, produccion de leche y consumo de alimento. Lo que sugiere que el extracto enzimatico obtenido del sustrato gastado de Pleurotus ostreatus, puede ser una alternativa para mejorar los parametros productivos de las cabras. Palabras clave: leche, extracto enzimatico, cabras.

The difference among animal species with which chorizo is made, resulting in changes in the techno-functional properties that affect the process and acceptance of product. Sausages made with meat from rabbit, pork and lamb sources were added with wheat fiber and dried at water activity of 0.94. The moisture content was not affected by the source, but it was reduced when fiber was added. The sausages without fiber showed a lower fat content than those samples with fiber. They can be considered stable at room temperature due to their acidity and drying degree. Regarding to the weight loss and diameter of the sausage parameters, there were no differences between source types, however, a reduction of diameter was observed with the addition of fiber. Sausages with lamb meat and fiber showed an increase in oxidation. Higher values of luminosity were obtained in pork sausages. The most preferred samples were the pork meat sausages with the presence of fiber.

Incorporation of two types of dietetic fiber (inulin and oligofructose) on fat reduced sausages was studied. Fat percent was reduced (30 to 15%). Shear stress was not affected by the incorporation of the dietetic fiber. Maximum shear force values were lower with inulin than with oligofructosacarides as fat replacer.

The recurrent use of antibiotics has given the guideline so that bacteria will develop resistance to drugs used in medicine, which is why recent investigations have been directed to evaluate natural sources such as plants or fungi, which can fight the bacteria. Here the antibacterial activity of spent substrate of Pleurotus ostreatus combined with medicinal plants was evaluated. We designed six mixtures (barley straw, barley straw/Chenopodium ambrosioides L., barley straw/Mentha piperita L., barley straw/Rosmarinus officinalis L., barley straw/Litsea glaucescens Kunth and barley straw/Tagetes lucid Cav) to be used as a substrate of cultivation of mushroom. These were recovered after the harvest. We obtained aqueous extracts from spent substrates and resuspended them to different concentrations (25, 50 and 100 mg mL-1). These were tested for antibacterial activity against Staphylococcus epidermidis, Bacillus subtilis and Escherichia coli; as a positive control we used azithromycin, cephalexin and dicloxacillin. The protocol was a completely randomized assay with a factorial arrangement design. The data were analyzed with PROC GLM, SAS. The spent substrate from Pleurotus ostreatus that contained Mentha piperita L. presented the largest zone of inhibition against Staphylococcus epidermidis (40.00 mm) which was similar to control antibiotics (40.00 mm). Second in toxicity was the spent substrate from barley straw extract (33.33 mm). In conclusion, the results suggest that it is possible to use the spent substrate of Pleurotus ostreatus as source of extracts with antibacterial activity, being the best option the combination of barley straw with Mentha piperita L.

141 p. Esta tesis estudia los compuestos volátiles de la carne de rumiante y el efecto que sobre los mismos tienen diversas condiciones de producción y cocinado. Para ello se realizaron cinco experimentos. El objetivo del primer experimento ha sido investigar la posible influencia de la penca del maguey sobre los componentes volátiles de la carne de ovino cocinada en contacto con la misma. El objetivo del segundo fue analizar el perfil volátil de la carne de alpaca con y sin olor a tola. El tercer experimento describe el contenido en los compuestos volátiles presentes en la grasa perirrenal de terneros tudancos criados mediante un sistema semi-extensivo o intensivo. El cuarto experimento describe el efecto de alimentar ovejas en lactación con distintos aceites vegetales (palma, soja, oliva y linaza) sobre los volátiles de la carne de los corderos lactantes. El objetivo del quinto experimento fue determinar si la inclusión de ácido carnósico en la dieta de corderos lactantes puede reducir la oxidación de lípidos de la carne

Water exists in foods in free and bound forms; only unbound water is available for microbial growth and biochemical reactions (Prior 1979; Troller 1980). Measurement of unbound water is termed water activity (A w ) and is defined as the ratio of partial vapor pressure of water in the air to the vapor pressure of water vapor in saturated air at the same temperature (Scott 1957). This measurement is numerically equal to the relative humidity at equilibrium expressed as a fraction. Techniques for measurement of A w have been reviewed by Prior (1979) and Troller and Christian (1978). In addition, two collaborative studies have compared the various methods (Labuza et al. 1976; Stoloff 1978). Bread is one of the oldest food products consumed by humans. There is clear evidence of its use by different civilizations since prehistoric times. Bread has been a popular product because of its nutritious properties, and this product uses common ingredients as salt, sugar, and yeast (Serna 1996). Bread is a basic food made with cereals, usually in the form of flour, and liquid means, usually water. One of the greatest differences in bread production is the addition of leavening. Bread can be identified by very different names according to its form, weight, color, texture, etc., and the way in which it is presented in different countries as well as in different localities. In Mexico, baking product consumption is high, where approximately 750 varieties of sweet bread exist (CANAIMPA 2007).

Nowadays, the uncontrolled use of antibiotics has created the problem of bacterial resistance to them, what has motivated the search for new alternatives of drug for the treatment of bacterial diseases. Here, we compare antimicrobial activity of spent substrate of mushroom Pleurotus ostreatus and Lentinula edodes, against Escherichia coli, Salmonella tiphymorium, Staphylococcus aureus and Micrococcus luteus. We designed two mixtures, barley straw to be used as a substrate of cultivation of mushroom Pleurotus ostreatus and oats or cedar for the cultivation of mushroom Lentinula edodes; and were obtained aqueous extracts from spent substrates; extracts were tested for antibacterial activity. The protocol was a completely randomized assay with a factorial arrangement design. The data were analyzed with PROC GLM, SAS. The results showed that in the case of Escherichia coli the greatest inhibition zone was of 12.66 mm at a concentration of 6 mg mL-1, with treatment of Lentinula edodes/Cedar; Salmonella tiphymorium showed a greatest inhibition zone of 31.10 mm to a concentration of 5.12 mg mL-1, with treatment of Pleurotus ostreatus/Barley straw; Staphylococcus aureus showed a greatest inhibition zone of 9.33 mm to a concentration of 100 mg mL-1, with the treatment of Lentinula edodes/Cedar and finaly, Micrococcus luteus showed a greatest inhibition zone of 15.00 mm to a concentration of 50 mg mL-1, with the treatment Lentinula edodes/Oats. In conclusion, the results suggest that it is possible to use indistinctly the spent substrate of Pleurotus ostreatus and Lentinula edodes as source of extracts with antibacterial activity.