Thermal properties of cumin seed

Thermal Properties of Minor Millet Grains and Flours

Methods for the measurement of thermal conductivity and diffusivity of foodstuffs

Thespecific heat, thermal conductivity and thermal diffusivity of whole and ground guna seed and kernel were evaluated and their change with moisture content and temperature investigated. The specific heat of whole and ground seed increased from 1391.1 to 3020.13 and from 1459.14 to 3058.15 J kg -1 K -1 , respectively, as the moisture content and temperature increased from 4.7 to 25.35% (d.b.) and 307.12 to 368 K. The specific heat of whole and ground kernel also increased from 2135.15 to 4275.56 and from 2173.4 to 4340.06 J kg -1 K -1 , respectively, as the moisture content and temperature increased from 5.6 to 19.13% (d.b.) and 308 to 368 K. The thermal conductivity of whole seed and kernel increased from 0.0711 to 0.1282 and 0.087 to 0.126 W m -1 K -1 , respectively, as the moisture content and temperature increased. Thermal conductivity of ground seed and kernel increased also from 0.1 25 to 0.223 and 0.107 to 0.191 W m -1 K -1 , respectively, as the moisture content and temperature increased. The thermal diffusivity of whole seed and kernel decreased from 8.5 10 -8 to 9.311 10 -8 and 3.42 10 -8 to 4.397 10 -8 m 2 s -1 , respectively, as the moisture content and temperature increased. The thermal diffu- sivity of ground seed and kernel decreased from 3 10 -7 to 8.468 10 -8 and 1.768 10 -7 to 4.214 10 -8 m 2 s -1 , respectively, as the moisture

Thermal properties of guna seed

OF DISSERTATION HEAT AND MASS TRANSFER IN BALED SWITCHGRASS FOR STORAGE AND BIOCONVERSION APPLICATIONS The temperature and moisture content of biomass feedstocks both play a critical role in minimizing storage and transportation costs, achieving effective bioconversion, and developing relevant postharvest quality models. Hence, this study characterizes the heat and mass transfer occurring within baled switchgrass through the development of a mathematical model describing the relevant thermal and physical properties of this specific substrate. This mathematical model accounts for the effect of internal heat generation and temperature-induced free convection within the material in order to improve prediction accuracy. Inclusion of these terms is considered novel in terms of similar biomass models. Two disparate length scales, characterizing both the overall bale structure (global domain) and the individual stems (local domain), are considered with different physical processes occurring on each scale. Material and fluid properties were based on the results of hydraulic conductivity experiments, moisture measurements and thermal analyses that were performed using the constant head method, TDR-based sensors and dual thermal probes, respectively. The unique contributions made by each of these components are also discussed in terms of their particular application within various storage and bioconversion operations. Model validation was performed with rectangular bales of switchgrass (102 x 46 x 36 cm3) stored in an environmental chamber with and without partial insulation to control directional heat transfer. Bale temperatures generally exhibited the same trend as ambient air; although initial periods of microbial growth and heat generation were observed. Moisture content uniformly declined during storage, thereby contributing to minimal heat generation in the latter phases of storage. The mathematical model agreed closely with experimental data for low moisture content levels in terms of describing the temperature and moisture distribution within the material. The inclusion of internal heat generation was found to be necessary for improving the prediction accuracy of the model; particularly in the initial stage of storage. However, the effects of natural convection exhibited minimal contribution to the heat transfer as conduction was observed as the predominate mechanism occurring throughout storage. The results of this study and the newly developed model are expected to enable the maintenance of baled biomass quality during storage and/or high-solids bioconversion.

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Heat and mass transfer in baled switchgrass for storage and bioconversion applications

Measurement of thermal conductivity of paddy grains and its by-products

India is the largest world’s largest milk producer, with 22% of global production. The fermentation of milk is considered to be the oldest method to increase its shelf life. Fermented dairy food products with a diverse microbiota have been an important component of our diet. These food products, besides being well preserved, serve as significant sources of proteins, vitamins, minerals, and other nutrients. The key contributors to the milk fermentation are lactic acid bacteria (LAB), comprised of an ecologically diverse population of microorganisms. However, although relatively limited, several fungal species (yeasts and molds) of different orders have also been well established to play an active role in fermented foods. With attractive health benefits, fermented food industries have not only been able to attract a large number of consumers, but also have a major impact on the economic growth of their country. To meet the ever-growing consumer demands, modern fermentation technologies rely on defined starter cultures possessing desirable characteristics that help to ensure high consistency and commercial viability. Unlike the early dairy fermentations which were the result of spontaneous activity of the indigenous microbiota of the milk, molecular-based approaches have the potential to design novel starters, facilitate accurate species identification, and develop products with diverse and complex flavor profiles. In vitro and in vivo studies are also investigating the probiotic potential of fungal species and their therapeutic approach for the prevention and treatment of several health disorders. 

K.K. Dua

Papers

Measurement of thermal conductivity of paddy grains and its by-products

Recent trends in fungal dairy fermented foods