Variations in nutritional profile of honey produced by various species of genus Apis

The medicinal attributes of honey appears to overshadow its importance as a functional food. Consequently, several literatures are rife with ancient uses of honey as complementary and alternative medicine, with relevance to modern day health care, supported by evidence-based clinical data, with little attention given to honey’s nutritional functions. The moisture contents of honey extracted from University of Veterinary and Animal Sciences, Lahore honey bee farm was 12.19% while that of natural source was 9.03 ± 1.63%. Similarly, ash and protein contents of farmed honey recorded were 0.37% and 5.22%, respectively. Whereas ash and protein contents of natural honey were 1.70 ± 1.98% and 6.10 ± 0.79%. Likewise fat, dietary fiber and carbohydrates contents of farmed source documented were 0.14%, 1.99% and 62.26% respectively. Although fat, dietary fiber and carbohydrates contents of honey taken from natural resource were 0.54 ± 0.28%, 2.76 ± 1.07% and 55.32 ± 2.91% respectively. Glucose and fructose contents of honey taken out from honeybee farm were 27% and 34% but natural source were 22.50 ± 2.12% and 28.50 ± 3.54%. Glucose and fructose contents of honey taken out from honeybee farm were 27% and 34% but natural source were 22.50 ± 2.12% and 28.50 ± 3.54%. Similarly, sucrose and maltose contents of farmed honey were 2.5% and 12% while in natural honey were 1.35 ± 0.49% and 8.00 ± 1.41% respectively. The present study indicates that such as moisture, carbohydrates, sucrose and maltose contents were higher farmed honey as compared to the natural honey. In our recommendation natural honey is better than farmed honey.

RELATIONSHIP BETWEEN MOISTURE CONTENT AND FLAMMABILITY OF CERRADO SPECIES IN SOUTHERN TOCANTINS

This study aimed to analyze the relationship between moisture content and flammability of nine plant species from the Cerrado in southern Tocantins. The species studied were: Machaerium brasiliense, Qualea grandiflora, Luehea grandiflora, Campomanesia guaviroba, Astronium fraxinifolium, Curatella americana, Bauhinia forficata, Vatairea macrocarpa, and Anacardium Occidentale. The plants were analyzed at four moisture contents (M1, M2, M3, and M4). For each level, 50 samples (1 g ± 0.1 g) of each species were collected, and 50 repetitions of burning were performed. The parameters analyzed were: time to ignition (TI), frequency of ignition (FI), duration of combustion (DC), combustion index (CI), flammability value (FV), and height of flames (HF). Our results showed that moisture contents influence flammability in Cerrado plant species. The correlation coefficients between moisture and flammability parameters were r = 0.951 (TI), r = -0.962 (DC), r = -0.977 (HF), and r = -0.988 (FI).

Physical and morphological characteristics of edible coatings based on pectin and guava by-products applied to guava pieces

ABSTRACT: Edible coatings based on polysaccharides have been applied on pieces of fruits and vegetables before drying because of their potential to improve physical and nutritional characteristics of dehydrated plant foods. In the present study, physical and thermal properties of pectin-based films, with and without the incorporation of by-products obtained from the processing of red guava, were determined. These properties allow one to predict the likely behaviour of these films when used as edible coatings on guava pieces, during and after their dehydration. Thus the structural and morphological characteristics and the physical, thermal and sorption properties of the films and of the fruit pulp were determined, using scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and the static gravimetric method to determine the water-sorption curves. The addition of by-products provided crystallinity to the pectin film, attributed to their cellulose content, and hardly altered the water retention capacity of the pectin films. However, the pectin contributed to presenting a slightly higher sorption moisture at equilibrium, as compared to the guava pulp. The glass transition temperatures reported at extremely low moisture contents, both in the pulp and in the films with added by-products, indicated that at intermediate moisture contents, the fruit/film ensemble was in the rubbery state at room temperatures, providing softness to the dehydrated product. The images showed good integration of the edible films with the surface of the guava pieces.

Kinetics, modeling and colorimetry of celery leaves dehydration by direct and mixed solar drying

In celery, leaves, roots, and fruit contain a high value in medicinal properties and are used to prepare syrups, tinctures, infusions, or oils; however, its leaves are commonly discarded, wasting their nutritional and medicinal content. The dehydration of these leaves is a conservation option, increasing their shelf life. This study analyzes direct and mixed solar drying (SD and SM) kinetics and their effect on celery leaves. The moisture contents, drying rate, water activity, and colorimetry were obtained. Moreover, the fitting of experimental data to the mathematical models proposed in the literature. The moisture content stabilized at 150 min in the SM at the shortest time with a maximum drying rate of 0.1179 g∙water/g∙ dm∙min. The initial and final water activity was 0.98 and 0.412 in the SM and 0.403 in the SD. The SD better conserved the leaf color, with a total color change (ΔE) of 2.56, while the value obtained with the SM was 5.42. The experimental results of both technologies were better adjusted to the model Two exponential terms with an R² of 0.999. The results show that the solar drying of the celery leaves is feasible, and a quality product is obtained sustainably.

Investigation of the Influence of Moisture Content on Fatigue Behaviour of HPC by Using DMA and XRCT

High-performance concrete (HPC) is a topic of current research and construction projects, due to its outstanding compressive strength and durability. In particular, its behaviour under high-cycle fatigue loading is the focus of current investigations, to further pave the way to highly challenging long-lasting constructions; e.g., bridges or offshore buildings. In order to investigate the behaviour of HPC with different moisture contents in more detail, a mixture of silica sand and basalt aggregate with a maximum grain size of 8 mm was investigated with three different moisture contents. For this purpose, cyclic compressive fatigue tests at a loading frequency of 10 Hz and different maximum stress levels were performed. The main focus was the moisture influence on the number of cycles to failure and the development of concrete temperature and strain. In a further step, only the mortar matrix was investigated. For this purpose, the mixture was produced without basalt, and the moisture influence was investigated on smaller-sized test specimens using dynamic mechanical analysis (DMA) and X-ray computed tomography (XRCT). It was shown that the moisture content of HPC had a significant influence on the fatigue damage behaviour due to the number of cycles to failure decreasing significantly with increased moisture. In addition, there was also an influence on the temperature development, as well as on the strain development. It was shown that increasing moisture content was associated with an increase in strain development. XRCT scans, in the course of the damage phases, showed an increase in internal cracks, and made their size visible. With the help of DMA as a new research method in the field of concrete research, we were also able to measure damage development related to a decrease in sample stiffness. Both methods, XRCT and DMA, can be listed as nondestructive methods, and thus can complement the known destructive test methods, such as light microscopy.

Experimental Study of the Creep Disturbance Effect and Acoustic Emission Characteristics of Mudstone with Different Moisture Contents

It is important to have a clear understanding of the creep characteristics of water-rich soft rocks under a dynamic load and the evolution of cracks because soft rock roadways in deep mines are very sensitive to disturbances, and instability and damage can easily occur under the impact of disturbances such as mining and blasting. In this study, a self-developed disturbed creep test bench was used to conduct graded loading creep disturbance tests on mudstone specimens with different moisture contents. The results show that an increase in the moisture content leads to a significant increase in the creep failure strain of mudstone, and the accelerated creep rate is greatly accelerated. Moreover, as the moisture content increases, the type of mudstone creep disturbance failure gradually changes from accelerated creep failure to disturbance failure. By analyzing the acoustic emission (AE) characteristics of the mudstone creep disturbance tests, it was found that the increase in the moisture content greatly weakens the AE count and the accumulated energy. In each stage of disturbance, the AE signals jumped, and the stability was restored at the end of the disturbance. As the load increased, the specimen entered the accelerated creep stage, the AE signal increased exponentially, and the internal cracks expanded rapidly until failure occurred. It is of great significance to carry out creep disturbance experiments and to analyze the evolution of the internal cracks in specimens with different moisture contents to maintain the long-term stability of deep soft rocks.

The Effect of Crop Residue Percentages and Their Chopped Size on Soil Compactibility

The advancement of technology and increasing use of mechanization in agriculture, as well as increasing size of agricultural machinery for farm capacity improvement, have led to soil compaction. In developed countries, various reports of the soil compaction impacts on the reduction of agricultural products have been provided. In developing countries, soil compaction represents a less-known issue and a its destructive nature in agriculture has not been sufficiently addressed. Furthermore, in developed countries, the soil is rich in organic matter due to conservation tillage; however, in Iran, conservation tillage is not possible to perform because of traditional agriculture and using old agricultural machinery. Therefore, plant residues are either removed from fields, or burned. However, sufficient content of organic matter in field can contribute to soil compaction mitigation. The aim of this study was to investigate the effect of percentage of crop residues and their size on soil compaction at different soil moisture contents. For these purposes, five different soil moisture contents (8, 10, 12, 14 and 16% based on dry soil weight) and 4 residue rates at 3 fragmentation sizes were observed in terms of soil compaction. At all different soil moisture contents and residue sizes, with increasing percentage of added straw to the soil, the soil displacement increased. Moreover, as the straw size increased, the initial displacement during compression decreased, e.g., the maximum displacements for straw percentage of 12% and soil moisture of 8% were 64, 62 and 60 mm considering the straw sizes of 1, 2.5 and 5 cm, respectively. With high residue percentage, the final soil density and soil compaction were lower due to the low specific density of straw relative to soil. Furthermore, with high percentage of straw, more deformations and displacements were occurred in the mixture due to large deformation of straws. The density changes of soil-straw mixture were more significant at high residue percentages.