Effect of ripening temperature on the texture of cow milk Kashkaval cheese

Texture development during ripening of cow milk Kashkaval cheese at different temperatures (9±1 °С, 11±1 °С and 13±1 °С) was studied. Texture parameters representing cheese hardness, cohesiveness, springiness, adhesiveness, gumminess and chewiness were determined by texture profile analysis. It was found that hardness, gumminess and adhesiveness of all studied samples increased, while springiness and cohesiveness decreased during ripening. An increase of chewiness values during the first stages of ripening was observed, followed by a decrease to the 60th day. It was found that ripening time, as well as ripening temperature had a significant effect on the changes in Kashakaval texture parameters. Cheese samples ripened at higher temperatures had lower values for hardness, cohesiveness, gumminess and chewiness. Ripening temperature had no significant effect on the changes in springiness and adhesiveness of the studied samples. The results obtained showed that by an appropriate combination of the two factors, ripening time and temperature, the changes in the Kashkaval cheese texture can be controlled, which is important for the quality of the final product

Postharvest quality and safety of fresh-cut melon fruits coated with water soluble chitosan films

The research presents the effect of novel edible coatings based on low molecular weight chitosan on some properties of fresh-cut melon fruits – weight loss, total soluble solids, total acidity, mechanical strength and bacteria growth. Three different compositions were used as coatings – pure chitosan, chitosan and Ca lactate and alginate/chitosan multilayers. It was shown that the additional alginate layer substantially improves the protective properties of pure chitosan coating, resulting in preservation of cell structure. Negligible negative effect on the antibacterial activity of pure chitosan is demonstrated

An Osmotic Model of the Growing Pollen Tube

Pollen tube growth is central to the sexual reproduction of plants and is a longstanding model for cellular tip growth. For rapid tip growth, cell wall deposition and hardening must balance the rate of osmotic water uptake, and this involves the control of turgor pressure. Pressure contributes directly to both the driving force for water entry and tip expansion causing thinning of wall material. Understanding tip growth requires an analysis of the coordination of these processes and their regulation. Here we develop a quantitative physiological model which includes water entry by osmosis, the incorporation of cell wall material and the spreading of that material as a film at the tip. Parameters of the model have been determined from the literature and from measurements, by light, confocal and electron microscopy, together with results from experiments made on dye entry and plasmolysis in Lilium longiflorum. The model yields values of variables such as osmotic and turgor pressure, growth rates and wall thickness. The model and its predictive capacity were tested by comparing programmed simulations with experimental observations following perturbations of the growth medium. The model explains the role of turgor pressure and its observed constancy during oscillations; the stability of wall thickness under different conditions, without which the cell would burst; and some surprising properties such as the need for restricting osmotic permeability to a constant area near the tip, which was experimentally confirmed. To achieve both constancy of pressure and wall thickness under the range of conditions observed in steady-state growth the model reveals the need for a sensor that detects the driving potential for water entry and controls the deposition rate of wall material at the tip

Research of the elasticity of transplant - growing substrates after watering

It gets more and more popular to grow transplants in different trays for the field vegetable growing. The best transplant-growing substrates in the world are made of peat. The peat is applied to provide an optimal supply of plants with water and air. To improve the water regulation and the structure of the mixtures there are often mineral matters used in different amounts. By measuring the physical properties of soil mixtures based on peat, the flexibility can be measured by Stable Micro System type table penetrometer. Our measuring confirmed the increase of bulk and flexibility of different kinds of peat by watering

Sensory and instrumental texture analysis of Bulgarian commercial pates

Abstract. The aim of this study was to characterize the textural differences between Bulgarian commercial pates with different ingredients and to adapt the used methods for later application in texture analysis of sterilized meat products. Texture parameters were studied by sensory and instrumental methods. The sensory panel was stated from students in similar age and was asked to fulfill a questionnaire about their likening the poultry pates bought from the commercial network. Nine points sensory scales were used, about appearance, colour, spreadability by knife to bread, flavor, consistency, taste, aftertaste and overall likening. The panelists were asked to rank the pates based on their colour, spreadability and consistency. Instrumental texture parameters – texture profile and spreadability work, were analyzed by Stable Micro Systems texture analyzer in Texture Profile Analysis (TPA) and compression methods. For further analysis of spreadability, the probes were scanned by flatbed scanner before and after compression and their area ratio was measured by image analysis method. The results of sensory analysis show that, the pate with duck meat received the highest liking based on the overall liking, followed by pate with turkey meat and pate from chicken meat and liver and the lowest liked was the pate with goose meat. Based on the sensory spreadability and consistency the hardest was the pate with goose meat followed by pate with turkey meat and pate from chicken meat and liver and the softest was the pate with duck meat. The results from instrumental spreadability and hardness showed positive correlations with the results of the sensory analysis