Tecnología en Alimentos

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  • Ítem
    Análisis de la exposición alimentaria diaria probable de la población a los benzoatos y sorbatos en alimentos procesados consumidos en Costa Rica
    (2024-02-07) Castro Coronado, Ana Laura; Esquivel Rodríguez, Patricia
    Se analizó la exposición alimentaria de la población costarricense a benzoatos y sorbatos para evaluar de seguridad del uso de estos preservantes. Esto se realizó con base en la información reportada del gasto en la Encuesta Nacional de Ingresos y Gastos de los Hogares (ENIGH) del 2018 por el Instituto Nacional de Estadística y Censos, la cual se utilizó para calcular el consumo medio diario per cápita de cada alimento. Con estos datos se determinó la Ingesta Diaria Máxima Teórica (IDMT) y la Ingesta Diaria Estimada (IDE). La IDE para sorbatos fue de 4195,87, y la Ingesta Diaria Aceptable (IDA) para hombres costarricenses es de 1906 y para mujeres de 1658. Para benzoatos la IDE fue de 3777,85, y la IDA es de 381 y 332, respectivamente, para hombres y mujeres. Es decir que el consumo podría superar los límites establecidos para la población, según lo estimado con el análisis realizado a partir de la Encuesta Nacional de Ingresos y Gastos de los Hogares del 2018. El alto consumo de benzoatos está dado mayoritariamente por la ingesta de productos de panadería (31%), alimentos en conserva (27%) y bebidas (10%). Mientras que la exposición a los sorbatos está relacionada principalmente con el consumo de quesos maduros (16%), bebidas (14%) y alimentos en conserva (12%). Según el análisis de consumo por medio de la herramienta de Recordatorio de 24 horas, se determinó que la IDE de sorbatos es menor que la IDA para adultos de acuerdo con el reporte de ingesta de alimentos. Sin embargo, la de benzoatos sobrepasó las dosis aceptables, inclusive en un 100%. Posteriormente se realizó un análisis para determinar si el uso de estos preservantes en las muestras seleccionadas de alto consumo a nivel nacional es necesario según los parámetros fisicoquímicos de la matriz, tipo de tratamiento térmico aplicado, tipo de empaque y temperatura de almacenamiento, con el fin de analizar si es posible disminuir o evitar su adición a los productos. En este análisis se determinó que, en el jugo de naranja, las bebidas energéticas, la pulpa de fruta, la salsa de tomate tipo kétchup, los aderezos bajos en grasa, la mayonesa y la mermelada, se puede valorar mantener solo uno de los dos preservantes, siempre que se optimicen los procesos de producción. Además, se podría evaluar la posibilidad de prescindir del uso de benzoatos y sorbatos en los embutidos, siropes de kola, las barras de cereal, la cajeta y las tortillas. En estas últimas siempre que se emplee un método de refrigeración para su conservación. La calidad de la materia prima, el seguimiento de los procesos de producción de acuerdo con lo normado y un buen análisis de vida útil, son factores indispensables para garantizar la seguridad microbiológica de los alimentos, lo cual es parte de lo que se debe tomar en cuenta a la hora de realizar cambios en la formulación de los preservantes.
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    Distribución, estabilidad y asociación de la aflatoxina m1 con las principales proteínas de la leche de vaca, durante la manufactura y almacenamiento de queso fresco similar al queso Turrialba elaborado en Costa Rica
    (2023) Chavarría Molina, Guadalupe; Wong González, Eric
    Las micotoxinas son productos naturales originados por el metabolismo secundario de varios hongos toxigénicos que existen en la naturaleza. Las aflatoxinas B1 (AFB1), B2 (AFB2), G1 (AFG1) y G2 (AFG2) son un grupo de toxinas cancerígenas producidas principalmente por los hongos A.parasiticus y A. flavus. Se encuentran comúnmente en cultivos, granos, piensos y forrajes de los que se alimentan los rumiantes y por lo tanto, puede estar presentes en la leche. Una vez ingerido por los mamíferos a través de la dieta o la lactancia, AFB1 se oxida en el hígado para dar lugar a AFM1; un potencial carcinógenico que puede ser encontrado en leche, queso y otros productos lácteos. A pesar de que su estructura está compuesta por átomos de oxígeno y dobles enlaces, se considera que AFM1 es muy poco soluble en agua y es termoestable; por lo tanto, los procesos de fabricación convencionales no lo eliminan de la leche. Como consecuencia, se puede encontrar en el suero y en diferentes tipos de queso. En este trabajo se buscó elucidar la distribución y reparto de AFM1 en queso fresco y suero durante su manufactura, así como determinar el nivel de interacción de dicha toxina con varias proteínas de la leche, queso y suero. Adicionalmente, se analizó el comportamiento de asociación in vitro de la caseína, a-lactoalbúmina, B- lactoglobulina, albúmina sérica bovina, lactoferrina y una mezcla de estas con una concentración fija de AFM1 después del entrecruzamiento covalente. Se analizó también la afinidad de las fracciones de caseina (a s, k y B) con la AFM1. Finalmente se estudio la estabilidad de la AFM1 en queso fresco durante el almacenamiento en presencia de un cultivo protector de bacterias ácido lácticas. Los resultados demuestran que hasta 70% de los niveles de AFM1 presente en leche enriquecida con 0.5 y 1.5 ug L-1 fue liberada en el suero durante la manufactura de queso fresco mediante proceso estandarizado. Las proteínas del suero y leche con más moléculas de AFM1 unidas fueron α-lactalbúmina y caseína con 88% y 81% respectivamente. La fracción de caseina que mostró mayor afinidad a la AFM1 fue la as caseína que unió el 100% de la AFM1 .También se observó una disminución sustancial, de hasta 75%, de la concentración de AFM1 durante el almacenamiento del queso por 28 días que correlaciona inversamente con los conteos de bacterias acido lácticas (r= -0,825, p= 0,011) Este conocimiento puede servir como base para intervenciones en la industria láctea con la intención de aumentar la seguridad del queso y otros productos lácteos.
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    Evaluación del efecto del tiempo de fermentación y condiciones de secado de cinco subvariedades de cacao (Theobroma cacao L.) cultivadas en Upala, Costa Rica, sobre el perfil de ácidos orgánicos, compuestos volátiles y péptidos precursores de aromas claves para su calidad final
    (2024) Alvarado Marenco, Priscilla; Wexler, Lea
    En el presente estudio se evaluó el efecto de tres tiempos de fermentación (3, 5 y 6 días) y tres tipos de secado con aire caliente a 40 °C (circulación continua, flujo transversal a 1 m/s y flujo transversal a 2 m/s) sobre el perfil de ácidos orgánicos, compuestos volátiles y péptidos precursores de aromas clave, de cinco subvariedades de cacao orgánico cultivadas en Upala, Costa Rica. Tres de ellas son originarias del territorio upaleño (Umm, Ucs, Uea), una trasladada desde Talamanca (TU) y una corresponde a una mezcla de clones de alta productividad (CL). La fermentación a nivel piloto se realizó en cajones de madera con 25 kg de cacao en baba cada uno, en un equipo con condiciones de temperatura (40 – 55 °C) y humedad relativa (80 - 85 %) controladas a lo largo del proceso. Posteriormente se secaron hasta alcanzar una humedad de 7,0 – 7,5 %. Los resultados obtenidos evidenciaron que los ácidos cítrico, succínico, láctico, tartárico, glucónico y málico tienen diferencias significativas (p≤0,05) entre subvariedades, y que la talamanqueña producida en Upala tiene una mayor diversidad de ácidos orgánicos. Con respecto al tiempo de fermentación, coincidiendo con las distintas etapas de la fermentación, se observaron diferencias significativas en la concentración (mg/100 g) de los ácidos cítrico, láctico y acético del día 3 con respecto al día 5 y 6; por otra parte, para un mismo día de fermentación, no existe diferencia significativa en el contenido de ácidos orgánicos de las muestras de los tres tipos de secador. Se identificaron 96 compuestos volátiles diferentes, por medio de HS-SPME-GC-MS, siendo la subvariedad upaleña Ucs la que tuvo mayor cantidad de compuestos previamente asociados con aromas (n=37) y la subvariedad Uea la que tuvo menos (n=28). Los compuestos se clasificaron en diez familias químicas, la mayoría pertenecientes a alcoholes, ácidos carboxílicos y ésteres. En todas las muestras para los tres tiempos de fermentación se identificaron compuestos asociados con notas características de chocolate, entre ellos la trimetil y la tetrametil pirazina. Se encontraron 31 compuestos que no muestran diferencia significativa (p>0,05) para la interacción entre la subvariedad y el día de fermentación. Compuestos volátiles de las subvariedades fermentadas Ucs y TU, producidas en la misma finca, se separaron del resto, y parecen no mostrar diferencia entre el día 5 y el día 6 de fermentación. Por otra parte, el tipo de secado no afecta significativamente el perfil de compuestos volátiles. La separación electroforética por SDS-PAGE de los péptidos presentes mostró que no hay diferencia significativa en la cantidad de estos péptidos en función del tiempo de fermentación ni del tipo de secado. Con respecto a la subvariedad, la única que presenta una diferencia significativa es la subvariedad upaleña Umm, que tiene péptidos de mayor peso molecular. El análisis multifactorial confirmó que las subvariedades se agrupan en función del día de fermentación, a la vez, evidenció relación entre la cantidad de péptidos precursores de aromas, la presencia de ácidos orgánicos, principalmente ácido cítrico, y los compuestos volátiles, con las distintas fases de la fermentación. Para una misma subvariedad y un mismo día de fermentación, el tipo de secado no tuvo efecto en ninguna de las variables respuesta estudiadas; sin embargo, sí se identificaron diferencias entre el cacao del día 3 y el cacao con 5 y 6 días de fermentación. Los resultados obtenidos aportan una base científica importante para continuar estudiando los compuestos clave que definen el perfil aromático del cacao upaleño, de manera que se pueda establecer la viabilidad de disminuir los tiempos asociados a los procesos de fermentación y secado sin afectar las características distintivas que le otorgan a este cacao la denominación de fino y de aroma.
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    Aprovechamiento integral de la Mosca Soldado Negra: Bioconversión, sostenibilidad y desafíos emergentes
    (2023) Bermúdez Serrano, Ileana Maricruz; Sánchez Velásquez, Óscar Abel
    The black soldier fly (BSF) has garnered the attention of the scientific community due to its outstanding efficiency in transforming organic waste into raw materials that can be incorporated into the value chain. A bibliometric and bibliographic review was conducted to elucidate the pivotal role played by the bioconversion of organic matter in shaping sustainable circular economy systems. The analysis revealed that black soldier fly larvae (BSFL) have proven effective in the bioconversion of common waste, such as household and livestock waste, yielding valuable biomass. Despite these advancements, the exploration of new sources of organic matter persists to mitigate its environmental impact. Emerging technologies enable the efficient processing of BSFL biomass, yielding substitutes for environmentally unfriendly materials. Although the literature emphasizes the advantages of BSF in constructing circular economy models, obstacles such as limited legislation and insufficient incentives for producers, concerns about pathogens and contaminants, and low public acceptance of this species are identified. However, the growing trend in scientific interest suggests that BSF could play a central role in building sustainable societies in the future.
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    Phytochemical and mineral composition of fruits and seeds of wild-growing Bactris guineensis (L.) H.E. Moore palms from Costa Rica
    (2020-12) Erşan, Sevcan; Berning, Julia C.; Esquivel Rodríguez, Patricia; Jiménez García, Víctor; Carle, Reinhold; May, Bianca; Schweiggert, Ralf M.; Steingass, Christof Björn
    In the present study, nutritionally relevant constituents of wild-growing B. guineensis palm fruit from Costa Rica were assessed. In the edible exo- and mesocarp, 24 soluble free and six insoluble bound phenolic compounds were found. Anthocyanins, catechin mono- and oligomers, quercetin O-glycosides, in addition to apigenin- and luteolin C-glycosides were identified in the soluble free fraction, totalling to 17 and 398 mg/100 g of fresh weight (FW) in the meso- and exocarp, respectively. The insoluble-bound phenolic compounds exclusively comprised phenolics acids (9.4 and 39 mg/100 g of FW, respectively). Among 15 different carotenoids, (all-E)-β-carotene and (all-E)-lutein prevailed. Total carotenoid levels in meso- and exocarp amounted to 363 and 1728 μg/100 g of FW, respectively. Among tocochromanols, merely α-tocopherol was found in quantifiable concentrations (230 and 2401 μg/100 g of FW, respectively). In the kernel, total lipids represented 34.1% of the dry matter, mainly consisting of saturated fatty acids (90.0%). Hereby, lauric (56.3%) and myristic acid (23.0%) were the most abundant ones. Nutritionally relevant elements of the exocarp, mesocarp, and kernel were assessed by ICP-MS. In particular, the kernel was rich in magnesium and iron (68 and 2.65 mg/100 g of FW, respectively) and hence, a good nutritional source for these elements. Concluding, the present study is the first detailed report on the composition of the edible fractions of B. guineensis fruit, highlighting the nutritional, but also the hitherto unexploited industrial potential of this underutilised crop.
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    Marine phenolic compounds: Sources, commercial value, and biological activities
    (2023) Fallas Rodríguez, Pilar; Murillo González, Laura; Rodríguez Vallejos, Evelyn Tatiana; Pérez Carvajal, Ana Mercedes
    The commercial value of phenolic compounds has increased in recent years due to their inherent health-related benefits. Marine phenolics are found in diverse natural sources such as seawater, macro- and microalgae, cyanobacteria, seaweeds, seagrasses, and sponges. Seaweed or marine algae extracts containing phenolic compounds have been patented and commercialized. These extracts have been applied to enhance various products in several industries, such as food and beverages, cosmetics and personal care, pharmaceutical, agricultural, and horticulture. Marine phenolic-enriched products have been commercialized by claiming several biological activities like antidiabetic, antiobesity, antihyperlipidemic, anticholesterolemic, cardioprotective, antihypertensive, neuroprotective, antioxidant, antiaging, and photoprotective. Commercial products such as food supplements and cosmetics have been obtained mainly from phloroglucinol and phlorotannin extracts. This chapter reviews the commercial value, uses, and applications of the most relevant phenolic compounds from marine sources.
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    11'-α-Tocomonoenol is the major α-tocomonoenol isomer in cyanobacteria and microalgae from Costa Rica
    (2022) Montoya Arroyo, Alexander; Lehnert, Katja; Lux, Peter Erwin; Jiménez García, Víctor; Esquivel Rodríguez, Patricia; Silva Benavides, Ana Margarita; Vetter, Walter; Frank, Jan
    α-Tocomonoenols are vitamin E-derivatives with a single double-bond in the tocochromanol sidechain. Currently, two congeners are known: 11′-α-tocomonoenol and 12′-α-tocomonoenol, the later better known as “marine-derived tocopherol” (MDT). Information regarding their presence in photosynthetic aquatic organisms is scarce. We thus determined vitamin E congeners and derivatives in microalgae and cyanobacteria to assess their potential as sources of α-tocomonoenols. Tocochromanols were extracted from freeze-dried cyanobacteria (Arthrospira platensis) and microalgae (Nannochloropsis oceanica, Chlorella vulgaris and Tetraselmis sp.) and quantified by HPLC-FLD. α-Tocomonoenol was quantified in N. oceanica and Tetraselmis sp. where it was the second most abundant tocochromanol following α-tocopherol. LC-MSn and GC-MS confirmed that 11′-α-tocomonoenol and not MDT was the predominant α-tocomonoenol form in evaluated cyanobacteria and microalgae. No significant correlations were observed between tocomonoenol or vitamin E contents and fatty acid profiles. In conclusion, microalgae and particularly Tetraselmis sp. are novel sources of 11′-α-tocomonoenol, a tocochromanol not previously reported in aquatic photosynthetic organisms.
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    Effect of processing on biofunctionality of selected tropical fruit juices
    (2022) Esquivel Rodríguez, Patricia; Usaga Barrientos, Jessie; Schweiggert, Ralf M.; Steingass, Christof Björn; Jiménez García, Víctor
    This review compiles the current state of knowledge on the effects of processing using thermal and nonthermal technologies and fermentation on selected compounds in potentially health-promoting tropical fruit juices, specifically those of pineapple, pitaya, guava, and papaya. The most relevant functional compounds in pineapple fruit are phenolic compounds, carotenoids, and vitamin C. Pitaya fruit functional properties are mainly defined by the presence of betalains, heat-labile molecules with high antioxidant potential. The guava fruit is very-well-known because of its high ascorbic acid contents and, depending on the genetic background, also lycopene and anthocyanins. Finally, the relevance of the papaya fruit relies mostly on high carotenoid contents and their role as precursors of vitamin A and as antioxidants. For every case, the pertinent functional constituents are summarized followed by a description of the effect of conventional and emerging processing strategies on their retention. Fermentation is also mentioned as an option to improve biofunctionality in certain cases.
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    Characterisation of acylated anthocyanins from red cabbage, purple sweet potato, and Tradescantia pallida leaves as natural food colourants by HPLC-DAD-ESI(+)-QTOF-MS/MS and ESI(+)-MSn analysis
    (2023) Steingass, Christof Björn; Burkhardt, Jonas; Bäumer, Vicky; Kumar, Keshav; Mibus Schoppe, Heiko; Zinkernagel, Jana; Esquivel Rodríguez, Patricia; Jiménez García, Víctor; Schweiggert, Ralf M.
    Anthocyanins in red cabbage, sweet potato, and Tradescantia pallida leaves were characterised. A total of 18 non–, mono-, and diacylated cyanidins was identified in red cabbage by high performance liquid chromatography-diode array detection coupled to high-resolution and multi-stage mass spectrometry. Sweet potato leaves contained 16 different cyanidin- and peonidin glycosides being predominantly mono- and diacylated. In T. pallida leaves, the tetra-acylated anthocyanin tradescantin prevailed. The large proportion of acylated anthocyanins resulted in a superior thermal stability during heating of aqueous model solutions (pH 3.0) coloured with red cabbage and purple sweet potato extracts as compared to that of a commercial Hibiscus-based food dye. However, their stability was still outperformed by that of the most stable Tradescantia extract. Comparing vis spectra from pH 1–10, the latter had an additional, uncommon absorption maximum at approx. 585 nm at slightly acidic to neutral pH values, yielding intensely red to purple colours.
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    Comprehensive review on carotenoid composition: Transformations during processing and storage of foods
    (2023) Meléndez Martínez, Antonio J.; Esquivel Rodríguez, Patricia; Rodriguez Amaya, Delia B.
    Stimulated by their multifaceted functions and actions, carotenoids have been among the most investigated food components, producing a voluminous, complicated, and sometimes inconsistent literature. This review puts into context developments in the last decade to have a comprehensive current knowledge on these valuable food constituents. Carotenoid analysis continues to show the wide biodiversity of carotenogenic foods and the many factors that affect the composition. Because of their instability, subject to multiple influencing factors, retention of carotenoids during processing and storage of food has been a daunting task. Since thermal processing may result in substantial carotenoid losses, thermal processes that are much faster than the conventional methods and nonthermal processing have been introduced. The processing conditions of nonthermal processing should, however, be well established so that microbial and enzymatic inactivation is achieved while maintaining nutrients and bioactive compounds. Instead of losses, higher carotenoid levels and bioaccessibility are sometimes reported for both thermal and nonthermal processing, attributed to greater extractability of carotenoids during analysis and greater release from the food matrix during digestion. Carotenoids differ markedly in their susceptibility to degradation, the epoxycarotenoids being most degradable. Results are mixed, however, in relation to the comparative stability of hydroxycarotenoids and carotenes. E-Z isomerization at sterically unhindered double bonds is now well documented. There is also more information about oxidative degradation, although more work is needed on this topic. It consists of epoxidation, cleavage to apocarotenoids and finally fragmention to low mass compounds. Enzymatic and non-enzymatic cleavage of carotenoids forms important aroma compounds but can also produce off-flavor.
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    Antimicrobial activities of phenolic extracts of coffee mucilage
    (2023-06) Chaves Ulate, Evelyn Carolina; Rodríguez Sánchez, César Augusto; Arias Echandi, María Laura; Esquivel Rodríguez, Patricia
    The inhibition exerted by ethanolic extracts of coffee mucilage on the growth of bacteria was studied by microdilution in agar. The growth inhibition effect was evaluated for pathogenic or food spoilage related bacteria (Pseudomonas aeruginosa (ATCC 27853), Alcaligenes sp. (UCR277), Serratia sp. (UCR299), Micrococcus luteus (ATCC4698), Escherichia coli (ATCC35150), Staphylococcus aureus (ATCC25923), Bacillus cereus (ATCC14579), Salmonella enterica subsp. enterica (ATCC 13311) and Listeria monocytogenes (SLCC4013)) and for bacteria associated with human intestinal biota (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus rhamnosus, Lactiplantibacillus plantarum subsp. plantarum). The most effective growth inhibition was observed for B. cereus (ATCC14579). The content of chlorogenic acid and caffeine in the ethanolic extracts was quantified by HPLC/DAD. The chlorogenic acid content in the extracts ranged from 2.67 to 4.76 mg/ml, while the caffeine content ranged from 1.24 to 6.48 mg/ml. Although ethanolic extracts of coffee berry mucilage inhibited the growth of B. cereus, this inhibition does not seem to be related to the caffeine or chlorogenic acid contents.
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    Is the R-index method for eliciting preference measures from the 9-point hedonic scale fit for purpose?
    (2022-08-27) Jara Solís, Fiorela; Araya Quesada, Yorleny; O'Mahony, Michael; Cubero Castillo, Elba
    The traditional protocol for using the 9-point hedonic scale for measuring multiple preferences among a set of products, involves assigning numbers (1–9) to the scale’s verbal categories, which are erroneously treated as interval data. Means of these numbers for each product are treated by parametric statistics to yield an ordinal series of means, representing the degrees of liking as the effect sizes for the products in the set. Accordingly, for preference, products with a higher liking mean scores are deemed as being preferred to products with lower mean scores. This gives only the direction of the preferences among the products in the set but not their strengths. These have to be surmised from the means that were significantly different. Recently, an alternative protocol for the 9-point hedonic scale was developed, using the ranks of the scores on the 9-point scale. It used an R-index analysis of these ranks directly to yield preference probabilities for comparisons among products as its effect sizes. Besides appropriate effect sizes, attention was drawn to the absence of questionable statistical assumptions as well as superior ergonomics. Answering a call for further research and confirmation, this paper challenged these early results and was more demanding than the original. Using smaller numbers of products, the results of the R-index analysis shadowed those for the traditional analysis as expected. For these conditions, the only advantage for the R-index analysis was its ergonomics. As the number of products under assessment were increased, another advantage emerged; it was the elimination of artifactual ties. This was confirmed by the number of cases that were significant for the R-index analysis but not for the traditional analysis. All previous experiments were confirmed as were a set of conclusions, which were illustrated by feasible case studies. Together they indicated that the R-index analysis is definitely fit for purpose.
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    Effect of Palmito cheese processing on sensory characteristics and degree of liking
    (2023) Marín Fonseca, Andrea; Víquez Barrantes, Diana; Cordero García, Marcia
    Introduction. The production of regional food with local and cultural identity has become an attractive business for small-scale producers because it allows them to market their products highlighting local ingredients and traditional processing that reflects the know-how of each region. One example is Pasta filata cheese. Objective. To identify sensory characteristics and level of liking for Costa Rican Pasta filata cheeses (Palmito cheese). Materials and methods. The project was carried out at the facilities of the University of Costa Rica, during 2015. Nineteen samples of Costa Rican Palmito cheese were used, with fourteen of them being produced by artisanal producers and five by industrial producers. The methodology of Generic Quantitative Descriptive Analysis (QDA) was followed, with ten trained judges defining twenty-one attributes. Agglomerative Hierarchical Clustering (AHC) and Principal Component Analysis (PCA) were conducted to relate the samples to their attributes. Acceptance testing was performed with one hundred consumers. Consumer AHC and external preference mapping were applied to correlate the results of the liking with those of the QDA. Results. Significant differences (p<0,05) among samples were obtained in the QDA for all attributes. The samples were grouped into three clusters based on similarity attributes. The PCA showed one group, primarily consisting of traditional cheeses, clustered by attributes such as acid and salty flavor, firmness, moisture, and stringy appearance. Another group, corresponding to refrigerated, pasteurized, and unpasteurized cheeses, had a higher intensity of yellow color, greasy texture, softness, and less stringy appearance. A final group, composed of one sample, had a lettuce flavor. Conclusion. Through the external preference mapping, it was concluded that consumers like the majority of industrial Palmito cheeses, but they prefer traditional ones with characteristics such as stringy and creamy flavor.
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    Características fisicoquímicas y sensoriales del dulce de leche caprino con inclusión de amaretto
    (2023) Malavassi Conejo, Pamela; Chacón Villalobos, Alejandro; Víquez Barrantes, Diana; Cordero García, Marcia
    Introducción. A nivel mundial, los lácteos bovinos son prevalentes, por lo que existe la necesidad de estudios enfocados en leches menos tradicionales, como la caprina. Objetivo. Evaluar el efecto de dos niveles de inclusión de amaretto sobre las características fisicoquímicas y sensoriales de un dulce de leche caprino. Materiales y métodos. Entre enero y septiembre de 2017, en la Universidad de Costa Rica, se elaboraron dulces de leche con dos proporciones (6 % y 9 %) de amaretto (licor dulce), las cuales fueron seleccionadas con base en dos grupos focales.Se evaluó el pH, grados Brix, aw, textura, color, y agrado sensorial. Resultados. Los dulces de leche con inclusión de 6 % y 9 % de amaretto obtuvieron las siguientes características de manera respectiva: 71,8 y 70, 8 °Brix, pH= 6,8 y 6,9, aw= 0,8, dureza= 1,3 y 0,3, adhesividad= 0,75 y 0,6, elasticidad= 23,0 y 21,0, L*= 33,0 y 33,4, a*= 11,3 y 11,4, b*= 26,2, c*= 28,5 y 28,6, h*= 66,7 y 66,4, con un agrado promedio de 7,3 y 7,7, y una intensión promedio de compra de 6,9 y 7,2. El análisis de conglomerados generó tres grupos de personas: G1 = 25,5 % de agrado medio de 4,7 y 6,2 por las formulaciones al 6 % y 9 %, respectivamente; G2 = 19,6 % de agrado medio de 8,5 y 5,5 por las formulaciones al 6 % y 9 %, respectivamente; y G3 = 54,9 % de agrado medio de 8,2 y 9,1 por las formulaciones al 6 % y 9 %, respectivamente. Conclusiones. La inclusión de amaretto en el dulce de leche caprino resultó ser el producto con mejor perfil. No se observaron diferencias significativas entre los dos niveles de inclusión de licor. Los resultados sugieren que ambos productos tuvieron características técnicas y un agrado apropiados.
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    Effect of high intensity ultrasound on main bioactive compounds, antioxidant capacity and color in orange juice
    (2022) Brenes León, Jimena; Guevara Mojica, María Fernanda; Wong González, Eric; Cortés Herrera, Carolina; Usaga Barrientos, Jessie; Rojas Garbanzo, Carolina
    Ultrasound is a useful alternative to thermal processing that can be applied to many food products and juices to aid with enzymes and microorganism inactivation and to improve the efficiency of unit operations generally applied in the food industry. The aim of this study was to evaluate the effect of a high-intensity sonication treatment (frequency 20 kHz; intensity 39.4 W/cm2) applied for treatment times from 0 to 105 min on the content of polyphenols, vitamin C, organic acids, and carotenoids, and on the hydrophilic and lipophilic antioxidant capacity and color of orange juice. Treatments were performed in triplicate and data was statistically analyzed. Sonication time did not have a significant effect (P > 0.05) on total polyphenols, total vitamin C, organic acid, and carotenoid contents, lipophilic antioxidant capacity, or juice color. The hydrophilic antioxidant activity and the lutein content increased significantly (P < 0.05) with increased sonication time. These results may be useful as a baseline for the development of sonication treatments that could be used in combination with other traditional and emerging processing approaches to protect the most important bioactive compounds and quality properties of orange juice.
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    The effectiveness of treating irrigation water using ultraviolet radiation or sulphuric acid fertilizer for reducing generic Escherichia coli on fresh produce—a controlled intervention trial
    (2021) Beauvais, Wendy; Englishbey, April K.; Marconi, Cristina Marchesan; Cholula, Uriel; Belias, Alexandra M.; Wemette, Michelle; Usaga Barrientos, Jessie; Churey, John J.; Worobo, Randy W.; Enciso, Juan; Anciso, Juan R.; Nightingale, Kendra; Ivanek, Renata
    Aims The aims of this study were to: (i) estimate the effectiveness of ultraviolet radiation (UV) and sulphuric acid-based fertilizer (SA), at reducing levels of generic Escherichia coli in surface irrigation water and on produce and surface soil in open produce fields; and (ii) describe the population dynamics of generic E. coli in produce fields. Methods and Results Spinach and cantaloupe plots were randomly assigned to control, UV or SA treatment groups. Irrigation water was inoculated with Rifampicin-resistant E. coli prior to treatment. More than 75% of UV- and SA-treated tank water samples had counts below the detection limit, compared to a mean count of 3·3 Log10 CFU per ml before treatment. Levels of Rifampicin-resistant E. coli in soil and produce both increased and decreased over 10–15 days after irrigation, depending on the plot and time-period. Conclusions UV and SA treatments effectively reduce the levels of E. coli in surface irrigation water. Their effectiveness at reducing contamination on produce was dependent on environmental conditions. Applying wait-times after irrigation and prior to harvest is not a reliable means of mitigating against contaminated produce. Significance and Impact of the Study The results are of timely importance for the agricultural industry as new FSMA guidelines require producers to demonstrate a low microbial load in irrigation water or allow producers to apply a wait-time to mitigate the risk of contaminated produce.
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    Inactivation of Salmonella and Escherichia coli in surface agricultural water using a commercial UV processing unit
    (2022) Usaga Barrientos, Jessie; Beauvais, Wendy; Englishbey, April K.; Marchesan Marconi, Cristina; Cholula, Uriel; Belias, Alexandra M.; Wemette, Michelle; Churey, John J.; Worobo, Randy W.; Enciso, Juan; Anciso, Juan R.; Nightingale, Kendra; Ivanek, Renata
    Treatment of agricultural water aids in the prevention of foodborne disease outbreaks linked to contaminated fresh produce. UV light is a suitable alternative for treating drinking water but is not always effective for surface irrigation water due to interference caused by turbidity and high microbial loads. The effectiveness of UV treatment for reducing Escherichia coli and Salmonella in surface water used in agriculture was evaluated. Six pond water samples were collected on each of 16 sampling dates over a 3-year period. On each corresponding testing date, three samples were inoculated with Salmonella enterica serovars Hartford, Montevideo, and Gaminara and the other three samples were inoculated with E. coli ATCC 25922, targeting a concentration of 7 log CFU/mL. Inoculated water was UV treated with a commercially available juice processing UV device at a constant UV dose of 14.2 mJ/cm2 and a turbulent flow regime. The effects of date, initial bacterial counts, and water pH and turbidity on log reductions of both microorganisms were determined. Initial bacterial counts and test date significantly predicted microbial reduction (multivariate P < 0.001), but neither pH nor turbidity influenced microbial reductions (P > 0.05). UV treatment reduced both Salmonella and E. coli by a mean of >6 log CFU/mL.
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    Headspace control and antimicrobials: Inhibition strategies to prevent the growth of Alicyclobacillus acidoterrestris in orange juice
    (2022) Gamboa Moreno, Paola María; Worsfold Butler, Jessica Joy; Davidovich Young, Gabriela; Acosta Montoya, Óscar Gerardo; Usaga Barrientos, Jessie
    Alicyclobacillus acidoterrestris can cause spoilage in orange juice that leads to consumer rejection. Six different orange juices were physiochemically characterized (pH, total soluble solids, titratable acidity, total polyphenols and vitamin C). A bottle for each sampling point per juice was filled (headspace: 40% volume) and inoculated with 102 -103 CFU per ml of A. acidoterrestris ATCC® 49025™ (heat shocked before inoculation: 75°C, 20 min). Samples were stored for 21 days at 45 ± 1°C and plate counted periodically on acidified YSG agar (pH 3·7) incubated at 45 ± 1°C for 3 days. The effect of headspace (6% versus 40% volume) on A. acidoterrestris growth was also evaluated. The effect of nisin (0·006, 0·003, 0·0015, and 0·00075%), sodium benzoate (0·1%), potassium sorbate (0·1%) and a mix of benzoate and sorbate (0·05% each) on A. acidoterrestris was additionally addressed. Alicyclobacillus acidoterrestris reached up to 107 CFU per ml in five of the six juices in less than 1 week. Headspace significantly impacted (P < 0·05) A. acidoterrestris maximum population, which reached the critical value of 5 log CFU per ml at 40% headspace. All preservatives, regardless of concentration, showed a bacteriostatic effect during 22 days of storage with no significant differences amongst treatments (P > 0·05).
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    Análisis de posibles peligros en leche materna donada. Revisión
    (2023) Víquez Barrantes, Diana; Incer González, Ana Isabel; Acosta Montoya, Óscar Gerardo; Usaga Barrientos, Jessie
    La leche materna donada es un recurso de alto valor que puede ser utilizado para la alimentación de neonatos hospitalizados y a término, por tanto, garantizar su inocuidad es imperativo. Esta revisión de literatura reúne los principales peligros de naturaleza física, química y microbiológica identificados en leche materna, con la intención de proveer una referencia que los consolide de tal forma que la información pueda ser utilizada por bancos de leche humana, gobiernos y agencias regulatorias para establecer mecanismos para su prevención y control. Se realizó una revisión de literatura entre agosto del 2021 y octubre del 2022, utilizando buscadores y descriptores específicos para peligros de transmisión alimentaria en leche materna. Se incluyeron estudios publicados en español o en inglés. Se identificaron 31 agentes biológicos patógenos incluyendo bacterias, virus y parásitos. Como peligros químicos se reportaron medicamentos, drogas, cafeína, infusiones herbales, micotoxinas, alérgenos, especias, suplementos nutricionales, contaminantes ambientales y desinfectantes. Se alerta sobre la presencia potencial de plástico y vidrio de tamaño menor a 7 mm proveniente del ambiente de extracción y recipientes. La presencia de peligros microbiológicos y químicos en leche materna puede darse por transmisión vertical, temperaturas inadecuadas durante el almacenamiento y contaminación en el proceso. La presencia de peligros físicos se relaciona con la manipulación de los implementos en etapas posteriores a la extracción. Se requiere prestar atención a los hábitos de la madre para prevenir peligros químicos, así como más investigación relacionada con micotoxinas en leche materna
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    Modelling the effect of salt concentration on the fate of listeria monocytogenes isolated from Costa Rican fresh cheeses
    (2021-07) Posada Izquierdo, Guiomar D.; Mazón Villegas, Beatriz; Redondo Solano, Mauricio; Huete Soto, Alejandra; Víquez Barrantes, Diana; Valero, Antonio; Fallas Jiménez, Paula; García Gimeno, Rosa María
    “Turrialba cheese” is a Costa Rican fresh cheese highly appreciated due to its sensory characteristics and artisanal production. As a ready-to-eat dairy product, its formulation could support Listeria monocytogenes growth. L. monocytogenes was isolated from 14.06% of the samples and the pathogen was able to grow under all tested conditions. Due to the increasing demand for low-salt products, the objective of this study was to determine the effect of salt concentration on the growth of pathogen isolates obtained from local cheese. Products from retail outlets in Costa Rica were analyzed for L. monocytogenes. These isolates were used to determine growth at 4 C for different salt concentration (0.5–5.2%). Kinetic curves were built and primary and secondary models developed. Finally, a validation study was performed using literature data. The R2 and Standard Error of fit of primary models were ranked from 0.964–0.993, and 0.197–0.443, respectively. An inverse relationship was observed between growth rate and salt concentration. A secondary model was obtained, with R2 = 0.962. The model was validated, and all values were Bf > 1, thus providing fail-safe estimations. These data were added to the free and easy-to-use predictive microbiology software “microHibro” which is used by food producers and regulators to assist in decision-making.