Theoretical Basis of Protocols for Seed Storage III. Optimum Moisture Contents for Pea Seeds Stored at Different Temperatures

Vertucci, Christina W.

doi:10.1006/anbo.1994.1151

Cited by 87 publications

(106 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Although the presence of glasses has been associated with increased storage stability of seeds and pollen, there is not much known about the relationship between molecular mobility and storage stability. Our data on molecular motion in pea axes and cattail pollen in relation to water content and temperature enable a comparison with storage behavior, which is also known to depend on water content and temperature (Vertucci et al, 1994;Buitink et al, 1998).…”

Section: Storage Stability In Relation To Molecular Mobility and Intrmentioning

confidence: 88%

“…The water content of optimum storage longevity was found to increase with decreasing temperatures of storage (45°C, 35°C, 25°C, 15°C, and 5°C). Water contents of optimum storage longevity for pea seeds stored in the light were derived from Vertucci et al (1994). With decreasing storage temperature (45°C, 35°C, 25°C, 15°C, 5°C, and Ϫ5°C), the water contents of optimum storage increased.…”

Section: Storage Stability In Relation To Molecular Mobility and Intrmentioning

confidence: 99%

See 1 more Smart Citation

Influence of Water Content and Temperature on Molecular Mobility and Intracellular Glasses in Seeds and Pollen

Buitink

Claessens

Hemminga³

et al. 1998

Plant Physiology

133

152

View full text Add to dashboard Cite

Although the occurrence of intracellular glasses in seeds and pollen has been established, physical properties such as rotational correlation times and viscosity have not been studied extensively. Using electron paramagnetic resonance spectroscopy, we examined changes in the molecular mobility of the hydrophilic nitroxide spin probe 3-carboxy-proxyl during melting of intracellular glasses in axes of pea (Pisum sativum L.) seeds and cattail (Typha latifolia L.) pollen. The rotational correlation time of the spin probe in intracellular glasses of both organisms was approximately 10 ؊3 s. Using the distance between the outer extrema of the electron paramagnetic resonance spectrum (2A zz ) as a measure of molecular mobility, we found a sharp increase in mobility at a definite temperature during heating. This temperature increased with decreasing water content of the samples. Differential scanning calorimetry data on these samples indicated that this sharp increase corresponded to melting of the glassy matrix. Molecular mobility was found to be inversely correlated with storage stability. With decreasing water content, the molecular mobility reached a minimum, and increased again at very low water content. Minimum mobility and maximum storage stability occurred at a similar water content. This correlation suggests that storage stability might be at least partially controlled by molecular mobility. At low temperatures, when storage longevity cannot be determined on a realistic time scale, 2A zz measurements can provide an estimate of the optimum storage conditions.

show abstract

Section: Storage Stability In Relation To Molecular Mobility and Intrmentioning

confidence: 88%

Section: Storage Stability In Relation To Molecular Mobility and Intrmentioning

confidence: 99%

Influence of Water Content and Temperature on Molecular Mobility and Intracellular Glasses in Seeds and Pollen

Buitink

Claessens

Hemminga³

et al. 1998

Plant Physiology

133

152

View full text Add to dashboard Cite

show abstract

“…Early models developed from storage experiments suggested that water and temperature were independent variables (Justice and Bass, 1978; Roberts and Ellis, 1989). However, theoretical considerations (Vertucci, 1992;Vertucci and Roos, 1993) and experimental data (Vertucci and Roos, 1993;Vertucci et al, 1994aVertucci et al, , 1994b have demonstrated that the effects of water and temperature on seed aging are interdependent. Conceptual models have been introduced to describe the interdependencies of WC and temperature on seed longevity.…”

mentioning

confidence: 99%

“…Research on aqueous glasses in relatively dry seeds has focused mainly on methods for detecting their presence in embryonic tissues of corn (defatted embryos, Williams and Leopold, 1989; intact axes, Bruni and Leopold, 1992a), soybean (Bruni and Leopold, 1992b), and red oak . The experimental evidence gathered from different techniques (reviewed by Williams, 1994) suggests that water in seed tissues with a WC >0.05 g/ g exhibits some of the thermodynamic and mechanical properties representative of a glassy state at <30"C. However, despite these studies, the evidence for a physiological role of intracellular glass in both storage stability and desiccation tolerance is still conjectural (Williams et al, 1993;Vertucci et al, 1994aVertucci et al, , 1994b. For example, the WC/temperature combinations that give a glass transition do not always correlate with the WC/ temperature combinations that induce the physiological changes associated with desiccation tolerance (Vertucci and Farrant, 1994) and seed aging (Vertucci, 1992;Vertucci and Roos, 1993;.…”

mentioning

confidence: 99%

A Calorimetric Study of the Glass Transition Behaviors in Axes of Bean Seeds with Relevance to Storage Stability

Leprince

Walters

1995

Plant Physiol.

View full text Add to dashboard Cite

Although the presence of intracellular aqueous glasses has been established in seeds, their physiological role in storage stability is s t i l l conjectural. Therefore, we examined, using differential scanning calorimetry, the thermal behavior of glass transitions in axes of bean (Phaseolus vulgaris 1.) with water contents (WC) between O and 1 g H,O/g dry weight (g/g) and temperatures between -120 and +120°C. Three types of thermal behaviors associated with the glass transition were observed. The appearance, the glass + liquid transition temperature, and the amount of energy released during these transitions were dependent on the tissue WC. No glass transitions were observed at WC lower than 0.03 and higher than 0.45 g/g. A brief exposure to 100°C altered the glass properties of tissues with WC between 0.03 and 0.08 g/g but did not affect the thermal behavior of glasses with higher WC, demonstrating that thermal history is important t o the intracellular glass behavior at lower WC. Correspondence of data from bean to models predicting the effects of glass components on the glass --z liquid transition temperature suggests that the intracellular glasses are composed of a highly complex sugar matrix, in which sugar and water molecules interact together and influence the glass properties. Our data provide evidente that additional glass properties must be characterized to understand the implications of a glassy state in storage stability of seeds.Water and temperature play a significant and fundamental role in determining the storage longevity of orthodox seeds. Early models developed from storage experiments suggested that water and temperature were independent variables (Justice and Bass, 1978; Roberts and Ellis, 1989). However, theoretical considerations (Vertucci, 1992;Vertucci and Roos, 1993) and experimental data (Vertucci and Roos, 1993;Vertucci et al., 1994aVertucci et al., , 1994b have demonstrated that the effects of water and temperature on seed aging are interdependent. Conceptual models have been introduced to describe the interdependencies of WC and temperature on seed longevity. They rely on the findings that the nature and kinetics of degradative reactions in seeds change according to the physical properties of water

show abstract

“…A diaphragm pump (Type: N022Sve, 220 V, 50 Hz, 0.08 kW, Dwyer Instruments Inc., USA) was used to move air into the fluidized bed and through the powder. Before the air was pumped into the fluidized bed, the temperature of the air was controlled by a water bath, which was kept at 25°C, and the humidity was controlled by bubbling the air through a bottle, which contained a saturated NaCl solution or a saturated CaCl 2 solution to get different air humidities (70-75% relative 346 Z. Liang, T. Langrish humidity for NaCl solution and 30-35% relative humidity for CaCl 2 solution) [8,15]. The line diagram in Figure 1 shows the apparatus that was used to treat skim milk powder.…”

Section: Methodsmentioning

confidence: 99%

Control of crystallization and caking of skim milk powder in fluidized beds: A preliminary study

Liang

Langrish

2010

Dairy Sci. Technol.

View full text Add to dashboard Cite

-A stirred fluidized bed has been used with the aim of crystallizing skim milk powder from spray drying without caking the powders. The skim milk powder was crystallized in a stirred fluidized bed, then a sorption box was used to characterize the stability and a standard flow tester for dairy powders was used to measure the flowability. The results showed that the samples from the fluidized bed did not adsorb as much water as the original samples, suggesting that the samples from the fluidized bed were more stable than the original samples. The results of the flowability tests showed that the samples from the stirred fluidized beds were significantly more free flowing than either the caked samples from the sorption box or the original samples. This preliminary study indicates that fluidized-bed processing is a promising method for crystallizing some dairy powders.lactose / crystallization / fluidization / sorption / flowability / dairy powderRésumé -Contrôle de la cristallisation et du mottage d'une poudre de lait écrémé en lits fluidisés. Étude préliminaire. Un lit fluidisé agité mécaniquement a été utilisé dans le but d'obtenir la cristallisation d'une poudre de lait écrémé après séchage par atomisation et d'éviter la prise en motte de la poudre. Après cristallisation de la poudre de lait écrémé en lit fluidisé agité, une boîte de sorption a été utilisée pour caractériser sa stabilité et l'écoulement a été mesuré dans un testeur classique pour les poudres laitières. Les résultats ont montré que les échantillons obtenus après passage sur lit fluidisé n'absorbaient pas autant d'eau que les échantillons originels, ce qui suggère une plus grande stabilité des échantillons obtenus par lit fluidisé. Les tests d'écoulement ont montré que les échantillons obtenus après passage sur lit fluidisé étaient significativement plus libres d'écoulement que les échantillons pris en motte de la boîte de sorption ou que les échantillons originels. Cette étude préliminaire indique que le traitement par lit fluidisé est une méthode prometteuse pour réaliser la cristallisation de certaines poudres laitières.lactose / cristallisation / fluidisation / sorption / écoulement / poudre laitière

show abstract

Theoretical Basis of Protocols for Seed Storage III. Optimum Moisture Contents for Pea Seeds Stored at Different Temperatures

Cited by 87 publications

References 27 publications

Influence of Water Content and Temperature on Molecular Mobility and Intracellular Glasses in Seeds and Pollen

Influence of Water Content and Temperature on Molecular Mobility and Intracellular Glasses in Seeds and Pollen

A Calorimetric Study of the Glass Transition Behaviors in Axes of Bean Seeds with Relevance to Storage Stability

Control of crystallization and caking of skim milk powder in fluidized beds: A preliminary study

Contact Info

Product

Resources

About