Potential of X-ray imaging to detect citrus granulation in different cultivars with progress in harvesting time

Granulation, a physiological disorder of citrus is manifested by shriveled juice sacs and internal dryness. Extractable juice in granulated tissue is drastically reduced as a consequence of gelatinization and secondary epidermis formation. Since, the defect cannot be detected externally it leads to consumer dissatisfaction and poor returns to farmers. Processing industry also faces huge economic loss due to reduction in the juice recovery from granulated fruit. In this context, here, we studied the possibility of developing an image processing algorithm through MATLAB software to detect granulation with advancement of maturity via X-ray micrographs. Fruit of eight citrus cultivars comprising of granulation susceptible and tolerant varieties harvested at four different intervals were exposed to X-rays. Voltage of 46 kV and current of 6.5 mA given to fruit for an exposure time of 320 mAs gave the best X-ray image contrasts. The developed algorithm could effectively distinguish the healthy and granulated fruit with an accuracy of 90% as validated by subsequent destructive analysis when estimated for four different harvesting dates. The imaging technique can be employed by the processors to determine the severity of granulation and to sort out fruit online which will help in saving economic losses.

Physicochemical, Thermal, Structural and Pasting Properties of Unconventional Starches from Ginger (Zingiber officinale) and White Yam (Dioscorea sp)

Abstract Ginger and white yam starches were investigated and compared with maize starch. Proximal composition, thermogravimetry, differential scanning calorimetry, microscopy, colourimetry, X-ray powder diffractometry and pasting profile were analysed. The unconventional starches presented higher protein and ash contents than the maize starch, that had the highest thermal stability. Higher gelatinisation temperatures were reported for ginger starch, and the enthalpy of the unconventional starches were similar. The maize starch presented the lowest gelatinisation values. For the corn starch the granules were polygonal and smaller than the unconventional starches, and oval shapes and larger diameters were found for the ginger and yam starches. The unconventional starches presented less brightness and a greater tendency to red and yellow. The maize and ginger starches had A-type diffraction patterns, while the white yam starch had a C-type pattern. The highest relative crystallinity was observed for the ginger starch and there were small differences between the yam and maize starches. Higher peak viscosity and final viscosity and lower pasting temperature were observed for the yam starch. Ginger starch showed the highest shear and stability of heating glue, so may be used in products processed under high temperatures; and yam starch can be used in acidic foods that require high viscosities.

Retrogradation of heat-gelatinized rice grain in sealed packaging: investigation of moisture relocation

Abstract The aggregation of water molecules inside heat-gelatinized rice grain due to retrogradation of the grain was investigated by textural change and scanning electron microscopy (SEM) analysis of cooked grains after storage at 11 °C in a sealed package. Relaxation tests using a disc-type tip showed an increase in hardness (strength) of the cooked grain as the degree of retrogradation increased with increasing storage time, measured by the α-amylase-iodine method. SEM analysis of the vacuum-dried cooked rice grain showed a gradual increase in crevices, which further developed into holes at the center of the granule with increasing storage time. The results suggest that the disruption of hydrogen bonds between water and starch molecules is the first step for the retrogradation of gelatinized rice grain stored in a hermetic environment to avoid drying, resulting in its increased hardness, followed by the aggregation of starch molecules with subsequent water extrusion.

Mecanismo de gelatinización del almidón nativo de banano exportable del Ecuador / Mecanismo de gelatinização do amido nativo de banana exportável do Equador / Gelatinization mechanism of native starch from exportable banana of Ecuador

El presente trabajo tuvo como objetivo fundamental estudiar el mecanismo de gelatinización del almidón nativo de banano de la especie Musa sapientum L. exportable del Ecuador. Se estudiaron las variedades Cavendish, Filipino, Valery y Orito, y a su vez, se estudió su potencial para ser añadido en alimentos que demanden características tecnológicas funcionales deseables como agentes espesantes, gelificantes y estabilizantes. También se determinó el tamaño, la forma de gránulos de almidón, temperatura de gelatinización y viscosidad máxima; obteniéndose los siguientes valores: de 25 a 35 μm; 77,7 a 80 °C y de 259 a 270 UB, respectivamente. Según los resultados obtenidos, el almidón nativo de banano de las variedades estudiadas, puede ser incorporado en la elaboración de alimentos que demanden las características mencionadas.

A presente pesquisa teve como principal objetivo estudar o mecanismo de gelatinização do amido nativo da banana exportável do Equador (Musa sapientum L). Foram estudadas as variedades de banana Cavendish, Filipino, Valery e Orito, também foi estudado seu potencial para ser adicionado em alimentos que requeiram características tecnológicas funcionais desejáveis como agentes espessantes, gelificantes e estabilizantes. Também foi determinado o tamanho, a forma dos grânulos de amido, temperatura de gelatinização e viscosidade máxima; foram obtidos os seguintes valores: 25 a 35 μm, 77,7 a 80 °C y 259 a 270 UB, respectivamente. Segundo os resultados obtidos, o amido nativo da banana das variedades estudadas, pode ser incorporado na elaboração de alimentos que demandem as características mencionadas.

The fundamental aim of this work was to research the mechanism of native starch gelatinization banana species Musa sapientum L, exportable Ecuador. Cavendish, Filipino, Valery and Orito, varieties were researched and in turn, we studied its potential to be added in foods that claim desirable functional technological features as thickening agents, gelling agents and stabilizers. The size, form starch granules, gelatinization temperature and maximum viscosity is also determined; obtaining the following values: 25 to 35 μm; 77.7 to 80 °C and 259 to 270 UB, respectively. According to the results, the native banana starch varieties researched can be incorporated into food processing demanding such features.

DIGESTIBILIDAD DE MATERIAS PRIMAS ENERGÉTICAS EXTRUSADAS EN LA ALIMENTACIÓN DE CODORNICES (Coturnix coturnix japonicus) / DIGESTIBILITY OF ENERGETIC RAW MATERIAL EXTRUDED IN QUAILS' FEEDING (Coturnix coturnix japonicas)

El calentamiento del almidón de los cereales durante el proceso de extrusión a temperaturas entre 60 y 80ºC, en presencia de agua hace que el gránulo se hinche y alcance la gelatinización, la cual tiene ventajas en cuanto al aumento de la digestibilidad de los nutrientes. Con el objetivo de determinar el coeficiente de digestibilidad de los nutrientes del almidón de maíz, el almidón de yuca, el sorgo y el arroz quebrado cuando son extrusados e incluidos en la dieta de codornices Coturnix coturnix japonicus, se utilizaron 175 codornices machos de 6 semanas de edad y peso promedio de 123±6,3 gramos, distribuidas en un diseño irrestrictamente al azar, con 5 tratamientos, 5 repeticiones por tratamiento y 7 animales por unidad experimental, y según el tratamiento se alimentaron con una dieta de referencia y cuatro dietas experimentales preparadas con 80% de la dieta referencia y 20% del ingrediente a evaluar. Después de un período de adaptación de 10 días, se dio inicio al período experimental con una duración de 10 días, tiempo durante el cual las codornices tuvieron agua y alimento ad libitum. Se realizó el análisis proximal de las dietas, de los alimentos y de las excretas; así mismo se determinaron sus valores de energía bruta por medio de una bomba calorimétrica adiabática; posteriormente se calcularon los coeficientes de digestibilidad total aparente y el valor de la energía metabolizable de los ingredientes. Los resultados fueron analizados por el ANOVA y la prueba de SNK (p<0,05) para establecer la diferencia estadística entre medias de tratamientos. En general todos los ingredientes presentaron altos coeficientes de digestibilidad de los nutrientes, pero, fueron el almidón de maíz y el almidón de yuca los que presentaron los mejores, al ser comparados con el sorgo y el arroz quebrado.

Heating starch from cereals during the extrusion process at temperatures between 60 and 80°C in presence of water makes the granule swell up and reach gelatinization, which has advantages regarding the digestibility of nutrients increase. With the aim to determine the coefficient of digestibility from corn starch, cassava starch, sorghum and broken rice nutrients when they are extruded and included in the diet of quails Coturnix coturnix japonicus, 175 male 6 weeks of age and an average weight of 123±6.3 g quails were used. The birds were distributed in a completely randomized design with 5 treatments, 5 repetitions per treatment and 7 animals per experimental unit and, depending on the treatment they were fed with a reference diet and four experimental diets prepared with 80% of the reference diet and 20% of the ingredient to be tested. After an adaptation period of 10 days, the experimental stage began in a period lasting 10 days during which quails were given water and food ad libitum. The proximal analysis of the diets, food and excreta was carried out; likewise their raw energy values were determined through an adiabatic calorimeter bomb. Later, the total apparent digestibility coefficient and value of energy of the ingredients that could be metabolized were calculated. The results were analyzed by ANOVA and Student Newman Keuls test (p<0.05) to establish the statistical difference between treatment means. In general all the ingredients had high nutrient digestibility coefficients, but corn starch and cassava starch presented the best when compared with sorghum and broken rice.

ISOLATION AND CHARACTERIZATION OF STARCH FROM MANGROVES Aegiceras corniculatum (L.) Blanco and Cynometra iripa Kostel.

The present investigation deals with the isolation and characterization of starch from mangroves Aegiceras corniculatum and Cynometra iripa. Aegiceras is one of the important mangrove genera, which is an indicator of fresh water influence. Cynometra iripa is critically endangered species from west coast of Maharashtra. The propagules of A. corniculatum are starchy, therefore the starch from these propagules was isolated and properties of starch were studied. From the fruits of Cynometra iripa starch was isolated. Isolated starch was employed to techniques such as scanning electron microscopy (SEM), gelatinization and X-ray diffraction. Starch granules are variable in size and shape. Starch granules of A. corniculatum are round, oval and lenticular in shape with an average size 5μm, while in C. iripa starch granules are round and oval in shape with an average size 7 μm. The gelatinization temperature range varies from 600C to 900C; while in C. iripa range varies from 500C to 1000C. The range of temperature in both the mangroves is comparatively higher than other starch sources.

Modificación fíiica del almidón de yuca y evalución de la susceptibilidad a laa hidrólisis enzimática por una alfa miilasa / Physial modificaation of cassava starh and evaluation of susceptibillity to enzyme hydrolysis by alpha amylase / Modificção físicca do amido de mandiocay avaliação do susceptibilidadee à hidrólise enzimática com uma alfa mmilase

Almidón de yuca comercial (variedad MTAI8) se sometió a modificación física por sinéresis, extrusión, gelatinización y secado por rodillos. Al almidón nativo y a los almidones modificados se les determinó su morfología, cristalinidad, distribución molecular y susceptibilidad a la hidrólisis enzimática con una alfa amilasa porcina pancreática. En los almidones modificados físicamente se incrementó el grado de hidrólisis, en comparación con el almidón nativo. Sin embargo no se observaron diferencias estadísticamente significativas en el grado de hidrólisis entre los almidones modificados. El patrón de difracción de rayos X tipo A, presentado por el almidón de yuca nativo y su propiedad birrefringente se alteraron por los pretratamientos, presentándose difractogramas de estructuras amorfas y pérdida de la cruz de malta en los almidones modificados. La microscopía electrónica de barrido (MEB) demostró alteración en la apariencia y estructura del gránulo nativo, dando lugar a partículas de formas irregulares con superficies fragmentadas y rugosas como resultado del proceso de modificación. La cromatografía de exclusión sobre sepharosa 6B confirmó la desaparición de la fracción de alto peso molecular presente en el almidón nativo, con el consecuente incremento de las fracciones de bajo peso molecular en los almidones modificados.

Cassava starch (MTAI 8 variety) was subjected to syneresis, gelatinization, extrusion and processing by drum dryers. The morphology, crystallinity, molecular weight distribution and susceptibility to enzyme hydrolysis by porcine pancreatic a-amylase were determined before and after the physical treatments. The physically modified starches increased the extent of a-amylolysis, compared to the native one. However, there were not significant differences in the degree of amylolisis between the treatments during the procedure. Both the X-ray pattern type-A, presentedinthecassavastarch, and its birrefringent property, observed in polarized light, were altered by the treatments causing amorphous structures and the loss of the Maltese cross. When the modified starches were observed n scann ng electron micrographs (SEM), an alteration in the appearance and structure of the native granule was shown, where particles with irregular shape and fragmented and wrinkled surfaces could be seen as a result of the modification process. The profile of the size exclusion chromatography on sepharose 6B showed two characteristic fractions of high and low molecular weight in the native starch, while in modified starches only one peak was obtained showing low molecular weight. The data showed that the treatments modified the physical structure of the starch granule, allowing more accessibility for the enzyme to the amorphous and crystalline regions of starch.

Amido de mandioca comercial (variedade MTAI 8) foi submetido a modificação física por sinérese, extrusão, gelatinização e secado por tambor. Foram determinados para o amido nativo e os amidos modificados a sua morfologia, cristalinidade, distribuição molecular y susceptibilidade à hidrólise enzimática com uma alfa amilase porcina pancreática. Nos amidos modificados fisicamente foi verificado um aumento do nível de hidrólise, em comparação com o amido nativo. Porém, não se observaram diferenças estatisticamente significativas no nível de hidrólise entre os almidões modificados. O padrão de difracção de raios-X tipo A apresentado pelo amido de mandioca nativo e a sua propriedade birrefringente, foram alterados pelos prétratamentos, apresentando-se difractogramas de estruturas amorfas y perda da cruz de malta nos almidões modificados. A microscopia electrónica de barrido (MEB) demonstrou alteração na aparência e estrutura do granulo nativo, dando lugar a partículas de formas irregulares com superfícies fragmentadas e rugosas como resultado do processo de modificação. A cromatografia de exclusão sobre sepharosa 6B corroborou a desaparição da fracção de alto peso molecular presente no amido nativo, com o consequente aumento das fracções de baixo peso molecular nos almidões modificados.

Efecto de la concentración de hidróxido de calcio y tiempo de cocción del grano de maíz (Zea mays L) nixtamalizado, sobre las características fisicoquímicas y reológicas del nixtamal / Effect of calcium hydroxide concentration and cooking time of corn grain (Zea mays L) nixtamalized, over physicochemical and rheological nixtamal characteristics

Se evaluó el efecto de la concentración de hidróxido de calcio (Ca(OH)2) y tiempo de cocción del grano de maíz sobre las propiedades fisicoquímicas y reológicas durante la nixtamalización tradicional. Se observó que a mayor concentración de Ca(OH)2 y mayor tiempo de cocción del grano, la temperatura de gelatinización aumentó significativamente. El maíz nixtamalizado con 2 g/100g de Ca(OH)2 y 60 min de tiempo de cocción, presentó mayor absorción de calcio, 0.152 g/100g, mostrando un aumento significativo respecto a la concentración inicial (500 g/100g). Todas las muestras presentaron un patrón de difracción de rayos X de almidón tipo A, con diferencias en la intensidad de la difracción. La viscosidad aparente del nixtamal disminuyó considerablemente al utilizar condiciones de procesamiento más altas. Se encontró que la capacidad de retención de agua aumentó con la temperatura.

The effect of calcium hydroxide (Ca(OH)2) concentration and cooking time on physicochemical and pasting properties of maize, during traditional nixtamalization was evaluated. It was observed that the higher the Ca(OH)2 concentration and cooking time the higher the gelatinization temperature. Grain samples treated with 2 g/100g of Ca(OH)2 and 60 min of cooking time presented higher calcium absorption (0.152 g/100g) showing a significant increment (500 g/100g). Results of X-ray diffraction showed that all the samples had X-ray diffraction pattern of starch type A, showing differences in the intensity of the diffraction as indicated by the percentage of cristallinity. The apparent viscosity of the nixtamal considerably decreased when the processes conditions were higher. Water retention capacity increased with temperature.

Estrutura dos grânulos de amido e sua relação com propriedades físico-químicas: [revisão] / Starch granules structure and its regards with physicochemical properties: [review]

Devido aos escassos trabalhos brasileiros sobre a estrutura dos grânulos de amido, o objetivo desta revisão foi demonstrar os avanços atuais na elucidação da arquitetura e da estrutura química desse polímero. Muitas pesquisas sobre a avaliação da relação existente entre a estrutura molecular do amido e seu comportamento em algumas propriedades físico-químicas sugerem que diversas características estruturais, tais como teor de amilose, distribuição de comprimento das cadeias de amilopectina e grau de cristalinidade no grânulo, estejam intimamente relacionadas a eventos associados à gelatinização e retrogradação, como inchamento do grânulo, lixiviação de amilose e/ou amilopectina, perda da estrutura radial (birrefringência), supra-molecular (cristalinidade) e molecular e recristalização. O foco principal desta revisão foi a compilação de estudos a fim de obter melhor entendimento da estrutura e das características dos componentes do amido e sua relação com propriedades físico-químicas, principalmente no que diz respeito à gelatinização e retrogradação, as quais apresentam grande importância nutricional e tecnológica.

Due to poor Brazilians work on the structure of starch granules, the purpose of this review was to demonstrate the advances in current understanding of architecture and chemical structure of this polymer. Many studies evaluating the relationship between the molecular structure of starch and its behavior in some physicochemical properties, suggest that several structural features, such as amylose content, amylopectin chain length distribution and the degree of crystallinity in the granule, are closely related to the events associated with gelatinization and retrogradation as starch granule swelling, amylose and/or amylopectin leaching, loss of radial structure (birefringence), supra-molecular (crystallinity) and molecular order, and recrystallization. The main focus of this review was to make a compiler of studies in order to gain better understanding of the granule structure and characteristics of starch components and physicochemical properties (gelatinization and retrogradation) that could play a significant role in improving the quality of different food products.

Gelatinized starch is more feasible for starch tolerance test / 中国药理学通报

Aim To study the effect of gelatinized starch on starch tolerance test.Methods Acarbose with gelatinized starch or ungelatinized starch was administered to ICR mice by gavage,and blood samples were collected at 30,60 and 120 minutes after treatment to measure blood glucose levels,whose rising percentage calculated at 30 min and AUC in every group.Results Compared with the ungelatinizedstarch group,blood glucose levels at 30 and 60 minutes after starch loading were significantly elevated in the gelatinized-starch group.Acarbose drastically flatted the elevation of blood glucose after gelatinized-starch load,but it had little effect on the ungelatinized-starch test.Conclusion It is more feasible to use gelatinized starch to carry out starch tolerance test than to use ungelatinized starch.