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GC–MS profiling, descriptive sensory analysis, and consumer acceptance of Costa Rican papaya (Carica papaya L.) fruit purees
No full textVolatiles of papaya purees from four Costa Rican cultivars were analysed by solid-phase microextraction and gas chromatography-mass spectrometry. A total of 83 volatiles was assigned in the purees, of which 19 were detected for the first time as papaya constituents. As revealed by multivariate statistics, i.e., principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), the purees may be allocated to terpene- and lactone-rich (‘SH-5’), ester-containing (‘Criolla’), and intermediate chemotypes (‘Pococí’ and ‘Silvestre’). Descriptive sensory analysis and a consumer acceptance test were additionally performed. Floral, fruity, and honey-like notes were perceived at significantly higher intensities in ‘SH-5’ puree. The latter descriptors strongly correlated with volatiles discriminating ‘SH-5’ in the PCA and PLS-DA, respectively. Consumer acceptance of the papaya purees differed significantly. ‘Pococí’ and ‘SH-5’ purees appear to be suitable for improving the nutritional value of blended fruit juices without impairing their sensory quality.German Academic Exchange Service/[]/DAAD/AlemaniaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de Alimento
Fate of spoilage and pathogenic microorganisms in acidified cold-filled hot pepper sauces
No full textConsumption of spicy foods and hot sauces is currently a popular trend worldwide. Shelf-stable acidified sauces are commonly hot-filled to ensure commercial sterility, but cold-fill-hold processes might also be suitable if microbial safety and stability are ensured. For this study, model acidified hot pepper sauces were developed and characterized. The effects of sauce pH and of two different organic acids on the survival of Pichia manshurica and Lactobacillus curvatus isolated from contaminated commercial hot sauces and on pathogenic Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes were assessed. Full factorial designs with three levels for pH (3.2, 3.5, and 3.9) and two for organic acid (citric and acetic) were used to determine the effects of these factors and their interactions on the survival of the microorganisms. Commercially sterile sauces were independently inoculated and kept at ambient temperature. Microbial counts were determined at different sampling times, depending on the treatment evaluated. Sauces acidified to pH 3.2 with citric or acetic acid were inoculated with cocktails of five strains or serotypes of the three pertinent pathogens, and inactivation curves were determined. Trials were performed in triplicate. A greater than 5-log reduction of P. manshurica and L. curvatus was achieved in less than 6 h in sauces adjusted to pH 3.2 with acetic acid. Greater than 5-log reductions of pathogenic bacteria were achieved 0.5 h after inoculation in sauces acidified to pH 3.2 with acetic acid. In contrast, at least 48 h was required to guarantee the same inactivation for the most tolerant pathogen when citric acid was used. Thus, a cold-fill-hold process may be a suitable alternative for acidified hot pepper sauces. Based on survival of the microorganisms evaluated in this study, microbial safety and stability can be achieved by adjusting the pH to 3.2 or less by the addition of acetic acid.Universidad de Costa Rica/[735-B5-246]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de Alimento
Mamey sapote fruit and carotenoid formulations derived there of are dietary sources of vitamin A-A comparative randomized cross-over study
No full textMamey sapote is a fruit rich in specific keto-carotenoids, namely sapotexanthin and cryptocapsin. Their chemical structure suggests their provitamin A activity, although their absorption and conversion to vitamin A remained to be demonstrated in humans. Besides structure-related factors, the fruit matrix might also hamper absorption and conversion efficiency. Therefore, we monitored carotenoid and vitamin A levels in triacylglycerol-rich lipoprotein (TRL) fractions in plasma of human participants after consumption of fresh sapote and a carotenoid-rich “matrix-free” formulation derived thereof. A randomized 2-way cross-over study was conducted to compare the post-prandial bioavailability of 0.8 mg sapotexanthin and 1.2–1.5 mg cryptocapsin from the above-mentioned test meals. Seven blood samples were drawn over 9.5 h after test meal consumption. Carotenoids and retinoids were quantitated in TRL fractions using HPLC-DAD. Sapotexanthin was absorbed by all participants from all meals, being ca. 36% more bioavailable from the “matrix-free” formulation (AUCmedian = 73.4 nmol∙h/L) than from the fresh fruit (AUCmedian = 54.0 nmol∙h/L; p ≤ 0.001). Cryptocapsin was only absorbed by 4 of 13 participants. The appearance of retinyl esters was observed in all participants independent of the test meal. Although the fruit matrix hampered carotenoid in vivo-bioavailability from sapote, the fruit clearly represents a valuable source of vitamin A for humans.German Academic Exchange Service/[]/DAAD/AlemaniaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de AlimentosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigación en Nutrición Animal (CINA)UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicin
Procesos de fermentación láctica
No full textMuchos de los procesos tradicionales en alimentos, se llevan a cabo por medio de un proceso de fermentación que responde al crecimiento de microorganismos. Algunos de estos alimentos son: panes, cervezas, cidras, vinos, quesos y yogurt (Lee, 2004). Durante un proceso de fermentación, las características de los alimentos van cambiando gradualmente, producto de la acción de enzimas generadas por microorganismos tales como bacterias, mohos y levaduras. Esta acción puede desarrollarse en condiciones aerobias (presencia de oxígeno) o en condiciones anaerobias (ausencia de oxígeno).Universidad de Costa Rica/[735-A8-110]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA
Physicochemical characteristics and polyphenolic compounds of cultivated blackberries in Costa Rica
No full textBACKGROUND:Blackberry fruits have recently gained attention because of their considerable amounts of polyphenols. OBJECTIVE:The aim of this study is to compare the physicochemical composition and contents of the main polyphenolic compounds of nine tropical highland blackberry genotypes grown in Costa Rica, and to evaluate the effect of environmental conditions and farming practices on physicochemical composition of fruits of 'Wine red thorn', which is the most widely grown blackberry genotype in Costa Rica. METHODS: Nine blackberry genotypes were harvested at fully ripe stage. Environmental conditions (geographic location and harvest season) and farming practices (organic and conventional techniques) were evaluated to determine their effects on physicochemical composition and polyphenolic compounds of 'Wine red thorn' blackberries. Anthocyanins and ellagitannins contents were determined by HPLC-DAD. RESULTS:The tropical highland blackberries contained appreciable levels of polyphenols. Anthocyanin content ranged from 2.9±0.1 to 12±1¿g cyanidin-3-glucoside equivalents/kg dry weight (DW); ellagitannin content ranged from 9.3±0.8 to 47±3¿g ellagic acid equivalents/kg DW. The influence of environmental conditions and farming practices on physicochemical characteristics of 'Wine red thorn' blackberries was significant (p¿<¿0.05). Blackberries harvested during the dry season had higher contents of sugars and anthocyanins than blackberries harvested during the rainy season. Organic blackberries had higher levels of ellagitannins than conventionally grown fruits. CONCLUSIONS:These data prove that Costa Rican blackberries are a good source of polyphenolic compounds, especially ellagitannins. Environmental and farming conditions can be exploited to obtain high quality blackberry fruits.Universidad de Costa Rica/[735-A8-125]/UCR/Costa RicaUniversidad de Costa Rica/[735-A5-521]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigaciones Agronómicas (CIA
Untargeted metabolomic profiling of urine in Wistar rats reveals enhanced bioavailability of soy isoflavones post short-term consumption of noni (Morinda citrifolia) juice
No full textMicrofiltered noni (Morinda citrifolia) juice was given by cannulation to 6 Wistar rats for 13 days; the rats were also fed on a standard food formulation containing whole soy bean flour. Twenty-four hour urine was collected before and after the nutritional intervention and was analyzed by UPLC-DAD/ESI+-QTof/MS to perform an untargeted metabolomics study. A supervised multivariate OSC-PLS-DA analysis was performed to discriminate between urine samples. Among the top 10 most discriminant ions, 8 compounds were tentatively identified. Six were significantly increased after noni juice ingestion: the glucuronidate form of S-(-) equol, daidzein, 2 isomers of dihydroxyquinoline, naphthyl and hippuric acid. On the contrary, the urinary excretion of the oligosaccharides stachyose and raffinose, was significantly reduced. Still highly statistically significant, glucuronated genistein and glycetein were also elevated in urine after noni juice ingestion. Noni juice appeared to considerably enhance the bioavailability of soy isoflavone and modify the metabolism of soy oligosaccharides.Universidad de Costa Rica/[735-A2-502]/UCR/Costa RicaUniversidad de Costa Rica/[735-A6-912]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Productos Naturales (CIPRONA)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones Farmacéuticas (INIFAR
Consumers’ perception of olive oil-based dressings evaluated by complementary techniques: Focus group and word association
No full textAromatized olive oils or olive oil based dressings have gained interest from the food industry since they expand the flavors offered to consumers. The present work compared the results obtained from the Word Association (WA) technique with those obtained from a Focus Group (FG) about olive oil, extra virgin olive oil and olive oil-based dressings, and analyzed the advantages of performing a FG prior to data analysis of WA. The results of the FG analyzed prior to the application of the WA technique allowed a better interpretation and understanding of the words associated by the consumers with each WA stimulus. The WA technique clearly differentiated preparations prepared from olive oil with the oils themselves, mainly in terms of taste, texture and combinations allowed.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA
Coupling osmotic dehydration with heat treatment for green papaya impregnated with blackberry juice solution
No full textSlices (1.5 mm thick) of green papaya were impregnated through osmotic dehydration with a blackberry juice–sucrose solution to produce an intermediate moisture product. The effect of processing temperature (T) and sucrose-added molality (msucrose) on mass transfer during the operation was assessed, using a response surface methodology (RSM). The RSM was used to model water loss, sugar and anthocyanin gain during the process. Increasing sucrose molality resulted in increasing water loss and sugar gain, but decreasing anthocyanin gain. Water transfer therefore limits anthocyanin impregnation, but not sucrose incorporation. Afterwards, the impact of heat treatment at high temperatures was analysed, using numerical simulation. The conditions of the combined process, designed to achieve an anthocyanin-rich final product, are low sucrose-added molalities (sucrose molality 50 ºC) for osmotic dehydration, coupled with high-temperature, short-time (HTST) heat treatments for product stabilisation.European Commission/[FP6-0015279]/EU/BélgicaUniversidad de Costa Rica/[735-A2-502]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de Alimento
Solid-state fermentation as a sustainable method for coffee pulp treatment and production of an extract rich in chlorogenic acids
No full textIn this study, coffee pulp was used as carbon source in solid-state fermentation to produce a phenol-rich extract for industrial applications. Fermentations were carried out at laboratory (0.4 kg), semi-pilot (12 kg) and pilot (90 kg) scales in presence of 2.5 g kg−1 yeast strains and with three different coffee pulp materials. The extract stability was investigated using different stabilizing agents: SO2, ascorbic and acetic acids. Then, a study was conducted to determine the effect of ultrasound treatment on extraction yields. Results showed that higher concentrations of chlorogenic acids were obtained with fermentation without ultrasound treatment and by adding sulfite at 0.5 wt% at 8 h of fermentation. Despite of variations in coffee pulp composition, the process was validated at semi-pilot and pilot scales, providing an extract 400% richer in chlorogenic acids (600 mg kg of coffee pulp) and with lower sugar amounts to separate during the downstream processing.Universidad de Costa Rica/[735-A2-502]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA
Valuable compounds in coffee by-products
No full textCoffee is extensively consumed as one of the most popular beverages, but at the same time it is a major source of organic residues. When not adequately disposed or processed, these residues are a cause of environmental and health concerns. Beneficial properties have been attributed to coffee, not only due to its caffeine contents, but also due to the presence of valuable compounds such as chlorogenic acids. The role of coffee as a beverage in prevention of diseases has been widely discussed. Among other reasons, increasing interest in coffee by-products has been ascribed to their potential as functional ingredients for food, pharmaceutical, and cosmetic industries. Pointing out to the industrial uses, it is important to consider that coffee pulp, which results from the coffee berry processing, comprises almost 45% of the cherry, being a valuable material for several purposes. Major polyphenols described in coffee pulp are flavan-3-ols (monomers and procyanidins), hydroxycinnamic acids, flavonols, and anthocyanidins. Moreover, additional by-products of coffee processing, such as the mucilage and the fiber fractions, parchment, and silverskin, have also been studied. The aim of this chapter is to review recent information related to the utilization of coffee processing by-products, focusing mainly on the health beneficial properties, but also on other uses when appropriate.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de AlimentosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro para Investigaciones en Granos y Semillas (CIGRAS