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1.
Crit Rev Food Sci Nutr ; : 1-34, 2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35816149

RESUMEN

Over the last 30 years, thousands of articles have appeared examining the effects of soaking and germinating brown rice (BR). Variable germination conditions and methods have been employed to measure different health-beneficial parameters in a diverse germplasm of BR. Research results may therefore appear inconsistent with occasional anomalies, and it may be difficult to reach consensus concerning expected trends. Herein, we amassed a comprehensive review on germinated brown rice (GBR), attempting to codify 133 peer-reviewed articles regarding the effects on 164 chemical parameters related to health and nutrition in BR and in value-added food products. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA-2020) approach was used to direct the flow of the literature search. A pair-wise comparison t-test was performed to deliver an overall approach indicating when a given compound has been found to significantly increase or decrease through germination, which was grouped into GABA and polyamines, γ-Oryzanol and phytosterols, phenolic compounds, vitamins, proteins and amino acids, starchy carbohydrates, free sugars, lipids, minerals and phytic acid. This resource will stimulate interest in germinating rice and optimistically help increase both production and consumption of highly nutritious, health-beneficial rice with pigmented bran.

2.
Foods ; 11(2)2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35053952

RESUMEN

Brown rice is nutritionally superior to white rice, yet oil rancidity can be problematic during processing and storage regarding sensory attributes. Germinating brown rice is known to generally increase some health-promoting compounds. In response to increasing the consumption of plant-based beverages, we sprouted unstabilized brown rice, using green technologies and saccharification enzymes for value-added beverages. 'Rondo' paddy rice was dehulled, sorted and germinated, and beverages were produced and compared against non-germinated brown and white brewers rice beverages. The preliminary germinated brown rice beverage contained significantly higher concentrations of total lipids, diacylglycerols, triacylglycerols, free sterols, phytosterol esters and oryzanols than both non-germinated brown and white rice beverages. White rice beverages had significantly higher free fatty acids. Significant lipid losses occurred during sieving, yet novel germinated brown rice beverages contained appreciable levels of valuable health-beneficial lipids, which appeared to form natural emulsions. Further pilot plant investigations should be scaled-up for pasteurization and adjusted through emulsification to ameliorate sieving losses.

3.
Foods ; 9(8)2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32751212

RESUMEN

Plant-based beverage consumption is increasing markedly. Value-added dehulled rice (Oryza sativa) germination was investigated to improve beverage qualities. Germinating brown rice has been shown to increase health-promoting compounds. Utilizing green processing, wholesome constituents, including bran, vitamins, minerals, oils, fiber and proteins should should convey forward into germinated brown rice beverages. Rapid visco-analyzer (RVA) data and trends established that brown rice, preheated brown rice and germinated brown rice had higher pasting temperatures than white rice. As pasting temperature in similar samples may be related to gelatinization, RVA helped guide the free-flowing processing protocol using temperatures slightly above those previously reported for Rondo gelatinization. Particle size analysis and viscometric evaluations indicate that the developed sprouted brown rice beverage is on track to have properties close to commercial samples, even though the sprouted brown rice beverage developed has no additives, fortifications, added oils or salts. Phenolics and γ-aminobutyric acid increased slightly in germinated brown rice, however, increases were not maintained throughout most stages of processing. Significantly lower inorganic arsenic levels (113 ng/g) were found in germinated (sprouted) brown rice, compared to Rondo white and brown rice, which is far below the USA threshold level of 200 ng/g.

4.
Food Sci Nutr ; 8(5): 2445-2457, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32405401

RESUMEN

Rice-derived beverages offer a non-soy, lactose-free, cholesterol and gluten-free food source, which may offer well-balanced nutrition. Brown rice is nutritionally superior to white rice but oil oxidation and rancidity can be problematic regarding organoleptics during processing and storage. Using green technologies, which do not rely upon stabilization, brown rice was sprouted and processed with enzymes to produce preliminary value-added rice beverages. Paddy (rough) Rondo rice was dehulled using a pilot plant dehusker, sorted and cleaned into brown rice (BRR), rinsed, and germinated under various conditions (times and temperatures). Germinated brown rice (GBR) was then assessed (96.7 ± 0.8% germination and coleoptile length 2.24 ± 0.83 mm) prior to developing a method to soften, wet mill, sieve and gelatinize the matrix. Moderate macronutrient catabolism based on proximate analysis (e.g., 27.0%, 30.9% and 28.9% protein, oil and carbohydrate loss, respectively) and significantly decreased phytic acid (71.6%) from BRR â†’ GBR along with processing efficiency were used to establish a germination and processing protocol engaging the natural enzymatic hydrolysis of starch and other biochemical changes. Based on rapid visco analyzer pasting properties in heated BRR, GBR sieving results and observations of stored crude beverages, proteins and oils apparently remained soluble and were conveyed forward into an the enzyme-treated solubilized oligosaccharide matrix, which could be a natural emulsion. A method for germinating and processing brown rice, leading to a completely green process and "free-flowing" soluble matrix to deliver preliminary sprouted brown rice beverages is presented.

5.
Food Sci Nutr ; 8(2): 1237-1243, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32148829

RESUMEN

Produce growers using surface or well water to irrigate their crops may require an appropriate water treatment system in place to meet the water quality standard imposed by FSMA Produce Safety Rule. This study evaluated the potential of using ultraviolet (UV-C) treatment in reducing the microbial population in agricultural water. Waters with turbidity levels ranging from 10.93 to 23.32 Nephelometric Turbidity Units (NTU) were prepared by mixing pond water and well water. The waters were inoculated with a cocktail of generic Escherichia coli (ATCC 23716, 25922, and 11775) and then treated with UV-C light (20-60 mJ/cm2). All tested doses of the UV-C treatment reduced the E. coli levels significantly (p < .05) in the water samples with the turbidity levels up to 23.32 NTU. The decrease in the turbidity from 23.32 to 10.93 NTU increased the level of reduction by more than 2.15 log most probable number (MPN)/100 ml). UV-C treatment effectively reduces microbial load in agriculture water; however, turbidity of water may significantly affect the disinfection efficacy. The study also demonstrated that sprinkler system resulted in a higher level of contamination of cantaloupes compared with drip irrigation. The results indicated that UV-C treatment could be a promising strategy in reducing the produce safety risks associated with irrigation water.

6.
Foods ; 8(7)2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31340517

RESUMEN

A low-cost method utilizing rice co-products to concentrate and stabilize blueberry polyphenols was developed that decreased the arsenic (As) content in rice bran. After concentration at 10 g/L, brown rice flour displayed a higher total anthocyanin content in both blueberry juice (2.7 mg/g) and pomace extract (2.6 mg/g) when compared to white rice flour. Defatted rice bran enriched with blueberry juice (10 g/L) had the highest concentration of polyphenols (16.0 mg/g), and defatted bran enriched with pomace extract had the highest concentration of anthocyanins (5.32 mg/g). Enriched rice flour and bran contained higher levels of anthocyanins when using pomace extracts. Polyphenols and anthocyanins were found to be highly stable at 37 °C in rice flour and bran samples combined with pomace extract. Polyphenol enrichment also produced lower total and inorganic arsenic (i-As) levels in defatted rice bran. Inorganic arsenic (i-As) concentrations in defatted rice bran enriched with blueberry juice and pomace extracts were reduced by 20.5% and 51.6%, respectively. Overall, rice flour and bran that are enriched with polyphenols and anthocyanins from blueberry pomace extracts are shelf and color stable, had low sugar content, and represent unique health-promoting food ingredients.

7.
Food Chem ; 229: 553-564, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28372214

RESUMEN

Pilot plant ultrafiltration was used to mimic the dominant U.S. commercial pomegranate juice extraction method (hydraulic pressing whole fruit), to deliver a not-from-concentrate (NFC) juice that was high-temperature short-time pasteurized and stored at 4 and 25°C. Recovered were 46 compounds, of which 38 were routinely isolated and subjected to analysis of variance to assess these NFC juices. Herein, 18 of the 21 consensus pomegranate compounds were recovered. Ultrafiltration resulted in significant decreases for many compounds. Conversely, pasteurization resulted in compound increases. Highly significant decreases in 12 consensus compounds were observed during storage. Principal component analysis demonstrated clearly which compounds were tightly associated, and how storage samples behaved very similarly, independent of temperature. Based on these data and previous work we reported, this solid-phase microextraction (SPME) method delivered a robust 'Wonderful' volatile profile in NFC juices that is likely superior qualitatively and perhaps quantitatively to typical commercial offerings.


Asunto(s)
Frutas/química , Lythraceae/química , Compuestos Orgánicos Volátiles/análisis
8.
J Sci Food Agric ; 97(2): 469-478, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27060570

RESUMEN

BACKGROUND: High antioxidant content and keen marketing have increased blueberry demand and increased local production which in turn mandates new uses for abundant harvests. Pilot scale processes were employed to investigate the anthocyanidin profiles, qualitative volatile compositions, and sensorial attributes in not-from-concentrate (NFC) 'Tifblue' rabbiteye blueberry juices. RESULTS: Processing prior to pasteurization generally resulted in increased L* and hue angle color, while a* , b* , and C* decreased. After 4 months pasteurized storage, non-clarified juice (NCP) lost 73.8% of total volatiles compared with 70.9% in clarified juice (CJP). There was a total anthocyanidin decrease of 84.5% and 85.5% after 4 months storage in NCP and CJP, respectively. Storage itself resulted in only 14.2% and 7.2% anthocyanidin loss after pasteurization in NCP and CJP. Storage significantly affected nine flavor properties in juices; however, there were no significant differences in the blueberry, strawberry, purple grape, floral, sweet aroma, or sweet tastes between processed and stored juices. CONCLUSIONS: NFC pasteurized blueberry juices maintained desirable flavors even though highly significant volatile and anthocyanidin losses occurred through processing. Maintenance of color and flavor indicate that NFC juices could have an advantage over more abusive methods often used in commercial juice operations. © 2016 Society of Chemical Industry.


Asunto(s)
Antocianinas/análisis , Arándanos Azules (Planta)/química , Manipulación de Alimentos/métodos , Jugos de Frutas y Vegetales/análisis , Frutas/química , Pasteurización , Compuestos Orgánicos Volátiles/análisis , Color , Calidad de los Alimentos , Humanos , Odorantes , Fenoles/análisis , Especificidad de la Especie , Gusto
9.
Food Chem ; 190: 643-656, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26213022

RESUMEN

Consumption and production of superfruits has been increasing. Highly colored fruits often have bitter and astringent components that may make them undesirable, especially when processed. Many pomegranate volatile reports involved commercial samples, complicated isolation methods, or blending and concentrating that were from arils only, cultivars other than 'Wonderful', or mixed cultivars. Solid phase microextraction (SPME), polydimethylsiloxane stir bar sorptive extraction, and Tenax adsorption were performed with freshly pressed 'Wonderful' juices, commercial juices and concentrates. Using SPME, 36 compounds were isolated in whole pressed 'Wonderful' juices, including 18 of the 21 consensus compounds. In arils-only juices, 41 compounds were isolated by SPME, including 17 of the consensus volatiles. Dramatic variation existed in volatiles recovered in commercial juices and isolation of consensus compounds was sporadic. This article and summary of the literature serves to possibly deliver an improved volatile data set via a rapid method for fresh and partially processed (pressed) pomegranates.


Asunto(s)
Frutas/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Lythraceae/química , Compuestos Orgánicos Volátiles/química , Microextracción en Fase Sólida/métodos
10.
J Food Sci ; 80(4): S818-27, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25816898

RESUMEN

Six cultivars of southern highbush (SHB) and rabbiteye (RE) blueberry samples were harvested on 2 different dates. Each treatment combination was pressed 2 times for repeated measures. Fresh juice was characterized for 18 flavor/taste/feeling factor attributes by a descriptive flavor panel. Each sample was measured for sugars, acids, anthocyanidins, Folin-Ciocalteu, soluble solids (BRIX), titratable acidity (TA), and antioxidant capacity (ORACFL ). Flavors were correlated with the composition and physicochemical data. Blueberry flavor correlated with 3 parameters, and negatively correlated with 2. Strawberry correlated with oxalic acid and negatively correlated with sucrose and quinic acid. Sweet aroma correlated with oxalic and citric acid, but negatively correlated with sucrose, quinic, and total acids. Sweet taste correlated with 11 parameters, including the anthocyanidins; and negatively correlated with 3 parameters. Neither bitter nor astringent correlated with any of the antioxidant parameters, but both correlated with total acids. Sour correlated with total acids and TA, while negatively correlating with pH and BRIX:TA. Throat burn correlated with total acids and TA. Principal component analysis negatively related blueberry, sweet aroma, and sweet to sour, bitter, astringent, tongue tingle, and tongue numbness. The information in this component was related to pH, TA, and BRIX:TA ratio. Another principal component related the nonblueberry fruit flavors to BRIX. This PC, also divided the SHB berries from the RE. This work shows that the impact of juice composition on flavor is very complicated and that estimating flavor with physicochemical parameters is complicated by the composition of the juice.


Asunto(s)
Ácidos/análisis , Antocianinas/análisis , Arándanos Azules (Planta) , Frutas/química , Preparaciones de Plantas/química , Sacarosa/análisis , Gusto , Antioxidantes/análisis , Bebidas/análisis , Carbohidratos/análisis , Humanos , Concentración de Iones de Hidrógeno , Odorantes , Lengua
11.
J Sci Food Agric ; 93(4): 828-37, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22821412

RESUMEN

BACKGROUND: Orange-fleshed cantaloupe melons have intense aroma and flavor but are very perishable during storage life. Fresh-cut processing enhances ethylene-mediated quality losses. Post-cutting 1-methylcyclopene (1-MCP) application to fresh-cut cantaloupe was evaluated for its effects on quality attributes, phytochemical content and aroma volatiles. RESULTS: Fresh-cut cantaloupe (Cucumis melo var. cantalupensis 'Fiesta') cubes treated with 1.0 µL L(-1) of 1-MCP for 24 h at 5 °C, packaged in vented plastic clamshells and stored under normal atmosphere at 5 °C for 9 days, preserved their soluble solids, total phenolics, total carotenoids and ß-carotene contents, but significant softening occurred. A significant increase of non-acetate esters and a decrease of aldehydes occurred during storage. Most quality attributes of fresh-cut cantaloupe were unaffected by the treatment with 1-MCP. 1-MCP-treated fresh-cut cantaloupe accumulated higher levels of propyl acetate, 2-methylbutyl acetate, methyl butanoate, methyl 2-methyl butanoate, methyl hexanoate, 2-methylbutyl alcohol and phenethyl alcohol, and lower levels of benzyl alcohol and heptanal than untreated controls. CONCLUSION: Post-cutting treatment with 1-MCP affected nine of the flavor-important volatiles, particularly those derived from the amino acids isoleucine and phenylalanine, but had no practical effect on phytochemicals or other quality attributes.


Asunto(s)
Cucumis melo/metabolismo , Ciclopropanos , Conservación de Alimentos/métodos , Frutas/metabolismo , Odorantes , Gusto , Compuestos Orgánicos Volátiles/metabolismo , Aldehídos/metabolismo , Carotenoides/metabolismo , Dieta , Ésteres/metabolismo , Conservantes de Alimentos , Almacenamiento de Alimentos/métodos , Humanos , Fenoles/metabolismo
12.
Appl Environ Microbiol ; 77(12): 4008-16, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21498750

RESUMEN

Recent outbreaks linked to Salmonella-contaminated produce heightened the need to develop simple, rapid, and accurate detection methods, particularly those capable of determining cell viability. In this study, we examined a novel strategy for the rapid detection and quantification of viable salmonellae in produce by coupling a simple propidium monoazide sample treatment with loop-mediated isothermal amplification (PMA-LAMP). We first designed and optimized a LAMP assay targeting Salmonella. Second, the performance of PMA-LAMP for detecting and quantifying viable salmonellae was determined. Finally, the assay was evaluated in experimentally contaminated produce items (cantaloupe, spinach, and tomato). Under the optimized condition, PMA-LAMP consistently gave negative results for heat-killed Salmonella cells with concentrations up to 10(8) CFU/ml (or CFU/g in produce). The detection limits of PMA-LAMP were 3.4 to 34 viable Salmonella cells in pure culture and 6.1 × 10(3) to 6.1 × 10(4) CFU/g in spiked produce samples. In comparison, PMA-PCR was up to 100-fold less sensitive. The correlation between LAMP time threshold (T(T)) values and viable Salmonella cell numbers was high (R(2) = 0.949 to 0.993), with a quantification range (10(2) to 10(5) CFU/reaction in pure culture and 10(4) to 10(7) CFU/g in produce) comparable to that of PMA in combination with quantitative real-time PCR (PMA-qPCR). The complete PMA-LAMP assay took about 3 h to complete when testing produce samples. In conclusion, this rapid, accurate, and simple method to detect and quantify viable Salmonella cells in produce may present a useful tool for the produce industry to better control potential microbial hazards in produce.


Asunto(s)
Azidas/metabolismo , Técnicas Bacteriológicas/métodos , Frutas/microbiología , Técnicas de Amplificación de Ácido Nucleico/métodos , Propidio/análogos & derivados , Salmonella/aislamiento & purificación , Verduras/microbiología , Viabilidad Microbiana , Propidio/metabolismo , Salmonella/genética , Salmonella/fisiología , Sensibilidad y Especificidad , Factores de Tiempo
13.
J Food Sci ; 76(7): S415-22, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22417559

RESUMEN

UNLABELLED: Previous research examined sanitation treatments on cut cantaloupe tissue to deliver germicidal and food safety effects. However, an apparent compromise between volatile loss and treatment/sampling efficacy appeared. Subsequently, a physiological and volatile reassessment of thinly sliced tissue against cubes was performed in cantaloupe tissue. Thin sliced cantaloupe L* decreased 27.5%, 40.5%, and 52.9% in 3, 2, and 1 mm thickness, respectively, compared with cut cubes after 3 d. Overall color (C) decreased in freshly prepared cubes (2.4%) and slices (14.4%) that were washed in cold water. Surface area per unit volume (SA: vol) in slices was 4.1 times greater than typical cubes, as reflected by substantial water loss (20.4%, 9.5%, and 6.7% in 1, 2 and 3-mm slices, respectively) after 1 d at 5 °C. Rinsing cubes and thin-slices with 5 °C deionized water resulted in roughly 15% soluble solids loss. SEM indicated 65.4% reduced cell size in 1-d old thin slices, evidenced by excessive cell damage and desiccation compared with stored fresh-cut cubes. In thin-sliced tissue exposed 15 min to an open atmosphere (mimic sanitation treatments), total esters decreased 92.8% and 95.8%, respectively, after 1 and 3 d storage at 5 °C. Washing tissue provided a boundary layer that reduced short-term ester losses in slices and cubes. Excessive cutting, sanitation treatment regimes, and storage can radically alter the desirable volatile profile of cut cantaloupe. Reduction of tissue size to maximize food-safety sanitation efficacy or delivering items to a niche market will need substantial work to engineer equipment and develop protocols to insure that product quality and volatiles are not compromised. PRACTICAL APPLICATION: We have demonstrated that cutting method and sampling protocol are critically important when using volatiles as a means by which to assess or interpret stress response and ascribe fresh-cut quality. Reduction of tissue size to maximize food-safety sanitation efficacy (for example, thin slices) will need substantial work to engineer equipment and design protocols to insure product quality and volatile profiles are not compromised.


Asunto(s)
Cucumis melo , Manipulación de Alimentos/métodos , Frutas/química , Frutas/ultraestructura , Compuestos Orgánicos Volátiles/análisis , Color , Cromatografía de Gases y Espectrometría de Masas , Microscopía Electrónica de Rastreo , Control de Calidad , Agua
14.
Crit Rev Food Sci Nutr ; 50(5): 369-89, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20373184

RESUMEN

The color, flavor, texture, and the nutritional value of fresh-cut fruit and vegetable products are factors critical to consumer acceptance and the success of these products. In this chapter, desirable and undesirable quality attributes of fresh-cut fruit and vegetable products are reviewed. Both instrumental and sensory measurements for determining these critical quality attributes are discussed. The advantages and disadvantages of sensory and instrumental quality measurements are described. A review of typical unit operations involved in the production of fresh-cut products is presented. The effects of fresh-cut processing techniques and treatments on sensory quality, including the appearance, texture, flavor (taste and aroma) of vegetables, and fruits are detailed.


Asunto(s)
Frutas , Valor Nutritivo , Verduras , Color , Sensación
15.
J Food Prot ; 72(11): 2313-20, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19903394

RESUMEN

The incidence of foodborne outbreaks linked to fresh produce has increased in the United States. Particularly noteworthy was the 2006 Escherichia coli O157:H7 outbreak associated with prepackaged baby spinach. This study aimed to determine whether E. coli O157:H7 would be present in the aerial leaf tissue of a growing spinach plant when introduced at various plant maturities and different inoculum levels in a greenhouse setting. Spinach seeds of a commercial variety were sown in 8-in. (20.32-cm) pots. After seed germination, two levels (10(3) and 10(7) CFU/ml) of an E. coli O157:H7 green fluorescent protein-expressing strain were introduced into the plant growth media weekly for a total of five times. Inoculated spinach plants were examined weekly for the presence of E. coli O157:H7 on leaves and in surrounding growth media. Among 120 spinach plant samples examined for internal leaf contamination, only one yielded a positive result. Surface leaf contamination occurred occasionally and clustered between 3 and 5 weeks of age, but not among leaves younger than 3 weeks of age. On the other hand, when inoculated at the 10(7) CFU/ml level, the E. coli O157:H7 green fluorescent protein strain survived the entire cultivation period, although with gradually reduced levels. The experiments demonstrated that internalization of E. coli O157:H7 of growing spinach plant leaves under greenhouse conditions was a rare event, but surface contamination did occur, primarily when the plants reached 3 weeks of age. The study provided important data to further assess the association between spinach age and potential contamination of E. coli O157:H7.


Asunto(s)
Seguridad de Productos para el Consumidor , Escherichia coli O157/fisiología , Contaminación de Alimentos/análisis , Spinacia oleracea/microbiología , Recuento de Colonia Microbiana , Medios de Cultivo/química , Brotes de Enfermedades/prevención & control , Escherichia coli O157/crecimiento & desarrollo , Microbiología de Alimentos , Proteínas Fluorescentes Verdes , Humanos , Hojas de la Planta/microbiología , Plantones/microbiología , Spinacia oleracea/crecimiento & desarrollo
16.
J Food Sci ; 72(4): S272-81, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17995790

RESUMEN

Recent studies demonstrated that ultraviolet (UV) radiation enhanced terpenoids and decreased esters in thin-sliced cantaloupe. In preliminary studies treating fresh juices with UV, terpenoid compounds that normally were not isolated, or found in minute quantities, were elevated and only low molecular weight alcohols, ketones, and aldehydes decreased. Subsequently terpenoid induction/oxidation in UV-treated cut cantaloupe was reinvestigated. UV exposure increased the concentrations of terpenoids in cantaloupe tissue. However, UV exposure alone was not the sole factor responsible for enhanced terpenoids. UV-enhanced terpenoid production appears to be both cultivar- and maturity-dependent. Concomitant decreases in the ester content of UV-treated samples occurred using a previously published system. Yet, we established that almost identical ester losses occurred in thinly sliced laminar tissue receiving 60 min UV or air exposure in an open system. Tissue samples that were exposed to UV in a closed system often did not suffer correspondingly equal ester loss. Marked tissue warming (4.3 +/- 0.5 degrees C in 60 min) occurred during UV treatments in thin-sliced tissue. Ester loss from cantaloupe tissue was caused by the experimental procedure, but not by UV treatment per se. These findings are supported by the observation that UV is not responsible for chemical transformations to ester bonds, esterase, and lipase decrease in stored cut cantaloupe, and no lipid oxidation volatiles were observed in thin-sliced control tissue, while oxidized terpenoids were recovered. Information gathered indicates that improper cutting, handling, sanitation treatment, and storage can radically alter the desirable volatile aroma profile in cut cantaloupe, and potentially lead to decreased consumer acceptance.


Asunto(s)
Cucumis melo/metabolismo , Cucumis melo/efectos de la radiación , Ésteres/metabolismo , Irradiación de Alimentos/métodos , Terpenos/efectos de la radiación , Rayos Ultravioleta , Cucumis melo/microbiología , Manipulación de Alimentos/métodos , Conservación de Alimentos/métodos , Oxidación-Reducción , Terpenos/metabolismo
17.
J Agric Food Chem ; 55(23): 9503-13, 2007 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-17944532

RESUMEN

Changes in post-cutting volatiles, quality, and sensory attributes during fresh-cut storage (4 degrees C) of cantaloupe (Cucumis melo L. var. Reticulatus, Naudin, cv. 'Sol Real') harvested at four distinct maturities (1/4-, 1/2-, 3/4-, and full-slip) were investigated after 0, 2, 5, 7, 9, 12, and 14 days in a 2-year study. Increased fruity and sweet taste attributes were negatively correlated with percent acetates, aromatic acetates, and total aromatic compounds, and positively correlated with percentage non-acetate esters. Ethyl hexanoate was strongly positively correlated with fruity and sweet taste. Cucurbit, water-like, hardness, cohesiveness, and denseness were positively correlated with percentage acetates, aromatic acetates, and total aromatic compounds, and negatively correlated with percentage non-acetate esters. Several non-acetate esters such as ethyl 2-methyl propanoate, ethyl butanoate, ethyl 2-methyl butanoate, and ethyl hexanoate were negatively (often strongly) correlated with cucurbit. Hardness was positively and strongly correlated with aromatic acetates and all aromatic (benzyl) compounds. In summary, firmer and denser cubes contained more acetates and fewer non-acetate esters. The apparently negative or undesirable attributes cucurbit and water-like were associated with higher acetates and aromatic compounds. Overall, relatively strong (year x maturity x day) correlations among numerous physiological, volatile, and sensory measures were found in this study. Highly significant (stronger) correlations were found in a year x day analysis used to pair maturity means; however, year and interaction effects require prudence when interpreting that data. Nonetheless, both analyses delivered almost identical trends, and strong correlations occurred even though samples were randomized from numerous fruits, per maturity, per juice catcher container, over 2 years. Further interpretation and biochemical explanation are needed to rationalize why mainly only non-acetate esters were highly correlated with desirable sensory and quality parameters.


Asunto(s)
Cucumis melo/química , Conservación de Alimentos , Frutas/química , Odorantes/análisis , Sensación , Acetatos/análisis , Caproatos/análisis , Frutas/crecimiento & desarrollo , Control de Calidad , Olfato , Gusto , Volatilización
18.
J Agric Food Chem ; 54(20): 7789-93, 2006 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-17002453

RESUMEN

Seedless triploid watermelons have increased in popularity since the early 1990s, and the demand for seedless fruit is on the rise. Sweetness and sugars are crucial breeding focuses for fruit quality. Volatiles also play an important role; yet, we found no literature for seedless varieties and no reports using solid-phase microextraction (SPME) in watermelon. The objective of this experiment was to identify volatile and semivolatile compounds in five seedless watermelon varieties using carboxen divinylbenzene polydimethylsiloxane solid-phase microextraction (SPME) with gas chromatography-mass spectrometry (GC-MS). Fully ripe watermelon was squeezed through miracloth to produce rapid juice extracts for immediate headspace SPME GC-MS. Aldehydes, alcohols, ketones, and one furan (2-pentyl furan, a lipid oxidation product) were recovered. On the basis of total ion count peak area, the most abundant compounds in five varieties were 3-nonen-1-ol/(E,Z)-2,6-nonadienal (16.5-28.2%), (E)-2-nonenal (10.6-22.5%), and (Z)-6-nonenal (2.0-11.3%). Hexanal was most abundant (37.7%) in one variety (Petite Perfection) [corrected] The most abundant ketone was 6-methyl-5-hepten-2-one (2.7-7.7%). Some sensory attributes reported for these compounds are melon, citrus, cucumber, orange, rose, floral, guava, violet, vegetable, green, grassy, herbaceous, pungent, fatty, sweet, and waxy. Identifying and relating these compounds to sensory attributes will allow for future monitoring of the critical flavor compounds in seedless watermelon after processing and throughout fresh-cut storage.


Asunto(s)
Citrullus/química , Frutas/química , Alcoholes/análisis , Aldehídos/análisis , Furanos/análisis , Cromatografía de Gases y Espectrometría de Masas , Cetonas/análisis , Semillas , Volatilización
19.
J Agric Food Chem ; 53(22): 8679-87, 2005 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-16248571

RESUMEN

Cantaloupe cultivar variability from various U.S. regions and growing seasons within a given year was evaluated. As expected, there was often considerable quality and volatile variation among cultivars. Eight of 11 cultivars met the standard U.S. No. 1 requirement for degrees Brix (> or =9), and in most cultivars, degrees Brix declined during fresh-cut storage at 4 degrees C. Hunter L (loss of lightness color value) and a (decline of typical orange hue) colors also generally declined during storage in most cultivars. Volatile ester compounds generally decreased during fresh-cut storage or exhibited a transient increase before declining after 5-7 days of storage. The relative percentage of acetate esters declined during storage in all cultivars, and declines were accompanied by simultaneous non-acetate ester increases. Slight imbalances in compound concentrations may alter the overall perception of desirable, typical "cantaloupe" aroma/flavor during fresh-cut storage. Upsetting the unique aroma balance through storage may negatively affect flavor and the consumer's perception of desirable attributes, even though total volatile levels might not decrease substantially until after 5-7 days in storage. Subtle volatile and quality decreases are likely to be exacerbated with immature-harvested cantaloupe and are likely in out-of-season exports that have likewise been harvested at less mature stages. Altogether, this study indicates the difficulty in procuring cantaloupes of consistent quality from local producers, in a given year, for domestically grown fruit.


Asunto(s)
Cucumis melo/química , Conservación de Alimentos , Frutas/química , Control de Calidad , Acetatos/análisis , Cromatografía de Gases , Ésteres/análisis , Cromatografía de Gases y Espectrometría de Masas , Estaciones del Año , Factores de Tiempo , Volatilización
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