Sensory and chemical evaluation of laboratory ensiled hybrid Napier grass prepared using Lactobacillus plantarum and propionic acid as additives

The present study was undertaken to evaluate silage made from hybrid Napier grass (Pennisetum purpureum) ensiled in the laboratory using various additives with regard to sensory as well as chemical characteristics. Four different silages were prepared viz., grass ensiled without additives (GS) as control, and grass silage with Lactobacillus plantarum at 1 x 105 CFU per gram of fresh forage (GSL), grass silage with propionic acid at the rate 0.45 kg per ton of fodder (GSA), and grass silage with combination of Lactobacillus plantarum (1 x 105 CFU per gram of fresh forage) and propionic acid (0.45 kg per ton of fodder) (GSLA) in triplicates. One from each triplicate was opened on 21, 30 and 45 days of ensiling and was evaluated for sensory (colour, aroma, presence or absence of extraneous matter) and chemical (pH, lactic acid, proximate analysis and fibre fractions) characteristics. From the overall results, it could be concluded that hybrid Napier grass, ensiled for 21 days using L. plantarum was effective in preserving its nutritive value

Effect of differential heat treatments on antibacterial activity of fermented goat milk

The present study was conducted to evaluate the effect of three different temperatures on the antibacterial potential of fermented goat milk.Goat milk is one of the naturalfoods to complete perfection.Bioactive peptides, the specific protein fragments that have a positive impact on body functions, can be produced during milk fermentation. Thanks to the starter cultures’ proteolytic activity.Fresh pooled goat milk sample collected was divided into four lots. One set was used for raw milk analysis and the remaining three were subjected to heat treatment at three different timetemperature combinations namely;72°C for 15 sec, 85°C for 10 min, and 121° C for 15 min. These samples were cooled immediately to 42ºC, inoculated with 0.04 % DVS yogurt culture,incubated at 42º C for 4 hrs, and then stored at 5±2°C for 21 days for storage studies. The analysis was carried out at 7-day intervals. An agar well diffusion assay was performed to assess the inhibitory activity ofWater-soluble peptide extracts (WSPE) of these samples against Bacillus cereus ATCC 10876, Escherichia coli NCIM 2685, Salmonella enterica ATCC 6017, and Staphylococcus aureus ATCC 25923. The milk that was heated to 85°C for 10 min before fermentation showed the highest antibacterial activity against E.coli during the 7th and 14th day of storage, withthe zone of inhibition measuredat 17±0.433mm and 21±0.55mm respectively.Thus, it can be concluded that milk heated at 85°C for 10 min had better antibacterial activity than the other two treatments

Study on hydrogen assisted cracking susceptibility of HSLA steel by implant test

DMR-249A is an indigenously developed high strength low alloy steel for Indian ship building industry for making ship-hull and is extensively used in the construction of war ships and submarines. Welding electrodes conforming to SFA 5.5 AWS E8018 C1 has been indigenously developed for welding of this steel using shielded metal arc welding process. In the present study, susceptibility to hydrogen assisted cracking of DMR-249A steel welds made using this electrode has been assessed using implant test. Implant tests were conducted using this electrode at two different levels of diffusible hydrogen, measured using gas chromatography technique. It is observed that both the steel and the welding consumable are not susceptible to hydrogen assisted cracking even with a high diffusible hydrogen level of 9 mL/100g of weld metal. In implant tests, specimen did not fracture even after loading to stress levels higher than the yield strength of the base metal. The good resistance of this steel and the welding consumable, even with high levels of diffusible hydrogen, is attributed to absence of a susceptible microstructure in both the weld metal and heat affected zone. Hence, this study shows that, in the absence of a susceptible microstructure, hydrogen assisted cracking is unlikely to occur even if hydrogen level is high. It also confirms that in welding of DMR-249A with indigenously developed E8018 C1 electrode, hydrogen assisted cracking is not a concern and no preheating is required to avoid it during welding

TECHNICAL NOTE: EFFECT OF FIRE RETARDANT TREATMENT ON MECHANICAL PROPERTIES OF MEDIUM-DENSITY COIR COMPOSITE BOARDS

Composite boards manufactured from natural fibers such as coir can be a useful substitute for wood and plywood. They can also be chemically treated to improve its fire-resistant capabilities. To be rendered useful as a construction material, the chemical treatment has to impart fire resistance without affecting its structural properties. This article investigates the effect of fire-retardant (FR) treatment on mechanical and physical properties of medium-density coir fiberboards when treated with a waterborne solution containing boron compounds using the method of hot and cold bath treatment. Physical properties such as density, MC, and thermal conductivity were determined to compare the performance of treated samples against untreated samples. Investigation of mechanical properties such as tensile strength, bending strength, tensile modulus, and flexural modulus were also carried out using a combination of tensile, bending, and compression tests. The results obtained were encouraging, and it was observed that the coir fiberboards after FR treatment retained much of their properties and in many cases, even improved marginally.