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Open access

Agnieszka Wójtowicz

Abstract

The aim of the research was to determine the selected properties of packaging materials applicable for vacuum and modified atmosphere packaging. Six samples of multilayer films with different composition were tested to evaluate the thickness, basic weight, density and the mechanical properties in elongation and puncture tests. Zwick/Roell apparatus equipped with elongation jaws and a puncture pin was used in the experiments. The tensile modulus, tensile strength, elongation at tensile strength, stress at break and work at break were investigated with the elongation test, whereas the breaking force, puncture work and extension at break were evaluated with the puncture test. The obtained results allow conclusion that the thickness and basic weight of the packaging films used in the vacuum system was higher comparing with the MAP system. Analyzing the results of the elongation modulus and stress at break it was reported that the materials used for food packaging in the MAP system were characterized with better properties, whereas elongation at the tensile strength was higher for films applied in the vacuum system, except for a film with a metalized layer. The highest resistance for puncture was evaluated for OPET/PE film used in MAP packaging. The extension at break under the puncture test was higher for films dedicated for vacuum packaging suggesting their better resistance for the mechanical damage by a thin pin. Several correlations between physical and mechanical properties of multilayer films were found.

Open access

Agnieszka Wróblewska and Grzegorz Wójtowicz

Bis(3-methyl-1-propene) ether and 3-(3-methyl-1-propene)-3-methyl-1,2-epoxypropane ether synthesis during the epoxidation of 1-butene-3-ol with hydrogen peroxide over the TS-2 catalyst

The influence of technological parameters on the transformation of 1-butene-3-ol (1B3O) to bis(3-methyl-1-propene) ether (2×1B3O ether) and 3-(3-methyl-1-propene)-3-methyl-1,2-epoxypropane ether (1B3Ox1,2EB3O ether) over the TS-2 catalyst was presented. The reaction was performed in a glass reactor at atmospheric pressure and in methanol medium (protic solvent). The optimum conditions of 2×1B3O ether and 1B3Ox1,2EB3O ether obtaining were established by the mathematical method of experiments design (rotatable-uniform design) and after the analyses of the layer drawings.

Open access

Agnieszka Wójtowicz and Leszek Mościcki

Effect of Wheat Bran Addition and Screw Speed on Microstructure and Textural Characteristics of Common Wheat Precooked Pasta-Like Products.

The present paper describes the wheat bran addition on microstructure, texture, colour and sensory characteristics of enriched precooked pasta-like products. Precooked pasta-like products were processed on a single screw extrusion-cooker TS-45 with L:D=16:1, shaped on the circular open die. Screw speed during the extrusion-cooking ranged from 60 to 120 rpm. Wheat bran were added in the amount from 5 to 25% of common wheat flour mass. The microstructure showed unmodified bran fractions at low screw speed, in turn higher rpm disrupted wheat bran cell walls. Hardness of dry pasta-like products, evaluated with the cutting test, was diminishing with a higher bran content in the recipe and was increasing with rpm applied. The firmness of hydrated products was decreasing with increasing bran addition (20 and 25% of bran in the recipe), whilst processing at low rpm caused poor quality of pasta-like products with great adhesiveness and stickiness. The higher bran content affected also the lower sensory notes. Colour measurement showed lower L* values for both raw and hydrated products with higher bran addition.

Open access

Agnieszka Ptak, Ewa Demczuk-Włodarczyk and Dorota Wójtowicz

Streszczenie

Profesjonalna opieka nad dzieckiem z przepukliną oponowo-rdzeniową jest powszechnie znana, niemniej jednak w Polsce nie stosuje się poprawy jakości życia poprzez terapię zajęciową. W Zakładzie Opiekuńczo-Leczniczym dla Dzieci w Jaszkotlu stosowana jest pionierska koncepcja terapii zajęciowej wzorowana na rozwiązaniach Occupational Therapy w USA [1]. Celem pracy jest przedstawienie wpływu indywidualnie opracowanego planu terapii zajęciowej na rozwój społeczny pięcioletniego dziecka z przepukliną oponowo-rdzeniową przebywającego w ośrodku w Jaszkotlu. Praca przedstawia planowany i celowy sposób prowadzenia terapii zajęciowej (TZ) dziecka, sposób monitorowania postępów terapeutycznych, jak również modyfikowania i programowania celów bliższych procesu terapeutycznego. Regułą nadrzędną programowania TZ jest uwzględnianie aktualnych możliwości i potrzeb pacjenta. Metodą wykorzystaną do oceny efektów terapii jest inwentarz PPAC H.C. Gunzburga w adaptacji Witkowskiego. Podsumowanie: prawidłowo zaprogramowany system pomocy dziecku w ramach terapii zajęciowej, spójnie uwzględniający osobę, środowisko i zajęcie (Person - Environment - Occupation PEO), umożliwia poprawę rozwoju społecznego, a tym samym wpływa na poprawę jakości życia.

Open access

Agnieszka Wójtowicz, Anna Kolasa and Leszek Mościcki

Abstract

The influence of buckwheat addition on physical properties, texture, colour and sensory characteristics of extruded corn snacks are presented in this paper. Snacks were prepared with a single screw extrusion-cooker TS-45 with L:D=12:1, shaped on the circular open die 3 mm, screw speed during processing was set to 120 rpm. Buckwheat flour was added in the amount from 10 to 50% of corn grits mass. Selected physical properties, cutting force and texture with Kramer cell were evaluated. The sensory characteristics and acceptability of buckwheat enriched snacks were evaluated. The expansion ratio lowered, whilst bulk density and durability increased with a higher level of buckwheat addition. Fracturability and hardness lowered with higher buckwheat amount in the recipe. Colour measurements showed lower L* and higher b* values with higher buckwheat addition. Higher buckwheat amount influenced lower sensory notes of snacks.

Open access

Abdallah Bouasla, Agnieszka Wójtowicz, Stanisław Juśko and Mohammed Nasreddine Zidoune

Abstract

The objective of the study was to determine the effect of extrusioncooking conditions (moisture content and screw speed) and recipe formulation on process efficiency and energy consumption during the extrusion-cooking of gluten-free rice-legumes products, shaped for spaghetti-type pasta. Process efficiency (Q) was determined through measurement of the pasta weight and energy consumption was determined using specific mechanical energy consumption (SME). According to the obtained results, screw speed had a great significant impact on Q and SME values which increased as screw speed increased. Moisture content of raw materials had also a significant effect on Q and SME mainly at low screw speed applied. The process efficiency increased with the increase of raw materials moisture content while reverse observations were noted for the energy consumption. On the contrary, variations of recipe formulations did not affect the measured parameters.

Open access

Arkadiusz Matysiak, Agnieszka Wójtowicz and Tomasz Oniszczuk

Abstract

The aim of the research was to determine the effect of extrusion conditions (various moisture content of raw materials and screw rotation speed), as well as the effect of recipe composition on the process efficiency and the energy consumption during treatment of potato and multigrain products. The efficiency of the extrusion process (Q) was determined by the mass of the product obtained at a given time for all prepared raw material mixtures and the process parameters used, while the specific mechanical energy demand was determined using the SME index. The obtained results allow to conclude that the level of raw materials moisture content had a greater impact on the efficiency and energy consumption of the extrusion process than the variable screw speed during the treatment. The efficiency of the process increased with the increasing moisture of the tested compositions, while a decrease in the requirements of SME was observed. The use of differentiated raw material compositions also influenced the Q and SME values determined during the tests.

Open access

Agnieszka Wójtowicz, Marta Zalewska-Korona, Ewa Jabłońska-Ryś, Krystyna Skalicka-Woźniak and Anna Oniszczuk

Abstract

The paper discusses the influence of the addition of freeze-dried tomatoes on the chemical composition and selected physical properties of extruded corn snacks. Corn grits were replaced with dried tomatoes in the amount from 5 to 30% of corn mass. The total lycopene and phenolic content, the scavenging ability and the ferric reducing antioxidant power were determined along with the content of neochlorogenic, chlorogenic, p-coumaric acids and rutin. Also evaluated were selected physical properties, colour and the sensory profile of corn snacks enriched with tomatoes. A greater tomato addition increased the volume of bioactive compounds, especially the total phenolic content. Snacks enriched with tomato exhibited a lower expansion ratio, water absorption and solubility indices, lightness and sensory characteristics but higher density, hardness and redness than corn snacks. Powdered tomato seems to be a functional additive with the high content of biologically-active compounds, and the enriched snacks displayed good physical properties if the tomato level did not exceed 20%. A higher amount of the additive significantly lowered the expansion as well as increased the hardness of snacks. Still, the corn products with 25 and 30% of powdered tomato were more valuable due to their much higher level of bioactive components compared with the regular corn snacks.

Open access

Dorota Kasprzak, Barbara Jodlowska-Jedrych, Katarzyna Borowska and Agnieszka Wojtowicz

Abstract

Lepidium meyenii, commonly known as Maca, is a Peruvian plant that grows high in the Andes, in areas over 4,000 meters above sea level. Its composition contains almost all of the essential amino acids and twenty of the essential fatty acids needed by man, as well as many vitamins, minerals and several sterols and glucosinolates. The specific and unique unsaturated acids and amides found only in this plant are the macaenes and macamides. Most valuable ingredients are contained within the hypocotyls. Maca comes in three forms, based on its root colour, yellow, red and black. Although used individually, consumption recommendations are usually for a mix of all three. Since Inca times, it has been considered as super food.

Although now mostly used in the form of a supplement, ongoing research does not exclude future applications of Maca as medicine. It is attributed to have an effect on male fertility (adding energy and vitality), and in regulating hormone secretion. In animal studies, Maca has been shown to have antioxidant, neuroprotective effects and antiviral activity. Moreover, it has been demonstrated to alleviate the effects of depression. In addition, there are reports that Maca reduces the development of cancer and osteoporosis, improves memory, facilitates concentration and alleviates the symptoms of menopause. The obtained results, however, require further analysis to confirm its effect. Currently, there is little information on toxicity, so there is a need for specialized research in this area, and on-going research concerns the most effective variety and form of preparation of Maca for administration to achieve best effects. The potential of Maca as medicine exists. The increasing pan-continental popularity of Maca has created the need for a better understanding of its action mechanisms.

Open access

Mateusz P. Kister, Katarzyna Borowska, Karolina A. Kister, Agnieszka Wojtowicz and Barbara Jodlowska-Jedrych

Abstract

Betel quid is one of the most commonly used psychoactive substances in the world, especially among Asian communities, just after caffeine, nicotine and alcohol. The mixture that is chewed usually contains betel leaves, areca nut and slaked lime, nonetheless, its ingredients and the preparation manner tend to vary. Areca nut contains four main alkaloids - arecoline, arecaidyne, guvacine and guvacoline that are responsible for its psychoactive effects. The act of betel chewing might have a negative impact on an overall health and can cause pathological lesions or diseases to develop and/or progress, both directly and indirectly. Also, it may happen that the negative impact of betel chewing on one system might have indirect harmful influence on another. Still an association has been drawn between betel chewing and the presence of metabolic diseases, cancers and proteinuria, as well as cardiovascular disorders - including hypertension, chronic renal failure, diabetics type II and obesity. Likewise, it is a known risk factor in the development of oral and esophagus cancer. Moreover, a correlation between betel chewing and smoking exists in that betel chewing might theoretically hinder the abandonment of tobacco smoking. Tissues of oral cavity and the upper part of digestive system are additionally exposed to the mechanical injuries caused by the areca nut. Therefore, they tend to be the most prone to be pathologically affected by betel quid chewing.