Quantificação de TBHQ (terc butil hidroquinona) e avaliação da estabilidade oxidativa em óleos de girassol comerciais

Sunflower oil is one of the vegetable oils most susceptible to oxidative reaction. Therefore the presence of natural (tocopherol) and/or synthetic (TBHQ) antioxidants is a prerequisite to secure the stability of this oil during its shelf life, especially with the increased use of PET packaging. On determining the total tocopherol content in 10 samples of deodorized sunflower oils, high losses in total tocopherol during deodorization were identified. In order to facilitate researche involving oxidative stability of vegetable oils, a method for isolated quantification of TBHQ using the isocratic elution system was developed.

Contaminantes voláteis provenientes de embalagens plásticas: desenvolvimento e validação de métodos analíticos

Plastic packaging materials intended for use in food packaging is an area of great interest from the scientific and economic point of view due to the irreversible internationalization and globalization process of food products. Nevertheless, a debate related to food safety aspects has emerged within the scientific community. Therefore, the development of analytical methods that allow identifying and quantifying chemical substances of toxicological potential in the packaging is considered essential. This article focuses on the main analytical methods, including validation parameters, as well as extraction and quantification techniques for determination of volatile organic compounds from food packaging materials.

Alteração do caráter hidrofílico de filmes de quitosana por tratamento de plasma de HMDS

Alteration in hydrophilicity feature of chitosan films by hexamethyldisilazane (HMDS) cold-plasma treatment is evaluated. All treated films were colorless and transparent with no apparent textural changes. The effect on surfaces was characterized through contact angle measurements, degree of swelling and water vapor permeation. A significant reduction in all of the hydrophilicity parameters was observed. It is assumed that the HMDS treatment forms nonpolar silicone type structures. The goal is to investigate the formation of a stable hydrophobic barrier in order to increase the chitosan films usefulness in packaging applications.

Validação de método analítico para determinar a migração de ε-caprolactama das embalagens para alimentos gordurosos

ε-Caprolactam (CAP) is a monomer of nylon 6 used as food packaging for bologna sausage, turkey blanquettes, fowl breast, pâtés and ham luncheon meat. After polymerization a part of the monomer can remain in the packaging and migrate into the food. The aim of this work was develop and validate a single laboratory method to determine CAP in ethanol 95% that simulates fatty food characteristics. Thus, linear range was 2 to 32 mg/L of CAP, detection and quantification limits were 0.83 and 1.63 mg/L, respectively. Repeatability showed Hor Rat values lower than 2 while recovery range was 97.5 to 106.5%. The method was considered adequate for purpose.

Filmes de amidos de mandioca modificados para recobrimento e conservação de uvas

In this article, films were produced with six types of cassava's starch mixed with gelatin and plasticized with sorbitol. These films were used in covering of grapes 'Benitaka' (Vitis vinifera L.) as biodegradable packaging. The acetylated starch film showed the best results in solubility, thickness and homogeneity, besides the less water loss the fruit, resulting in better coverage, increasing the shelf life fruits in 12 days. These results demonstrate the great potential of using films in food conservation, adding value to agricultural activity and helping to reduce non-biodegradable plastics in the environment.

Determinação de compostos carbonilados e carboxilados em derivados de petróleo

Although metals and nitrogen/sulfur compounds have been the main concern of the petroleum industry, issues concerning the harmful effects on catalysts poisoning and product contamination by other contaminants such as oxygen-containing compounds have been raised. Trace amounts of carbonyl and carboxyl compounds in petroleum products can lead to catalyst poisoning. Additionally, oxygenates may be present in final polyethylene and polypropylene resins, affecting the quality of food packaging. In this work, we reviewed potential analytical approaches for oxygenates determination in petroleum products and report the features of each potential technique.

O sistema globalmente harmonizado de classificação e rotulagem de produtos químicos (GHS): uma introdução para sua aplicação em laboratórios de ensino e pesquisa acadêmica

The present article provides an overview of the Globally Harmonised System of Classification, Labelling and Packaging of Chemicals (GHS) and its implementation in Brazil. Although Classification and Packaging is beyond the scope of the responsibility of academic chemists, labelling of chemicals used in academic laboratories will be required by the competent authorities to ensure the safety of students and staff. Therefore, academic teachers and researchers responsible should be familiarised with the GHS principles outlined here and at least be able to label, by applying these principles, mixtures of substances previously classified by the competent authorities.

Compósitos biodegradáveis de amido de mandioca e resíduos da agroindústria

The objectives of this work were to produce biodegradable composites using starch and different agro-industrial wastes (coconut fiber, soy bran and sugarcane bagasse) using a baking process, and to study the effects of these components on the resultant composite properties. The addition of different residues yielded trays with different properties. Samples manufactured with soy bran showed the highest density and water uptake at relative humidities ≥ 60%. The addition of sugarcane bagasse resulted in less dense and resistant samples whereas coconut fiber composites showed the highest breaking stress. The samples fabricated in this study represent an alternative packaging option for foods with low water content.

Produtos químicos perigosos utilizados em laboratórios de ensino: proposta e exemplos para indicação de seus perigos no rótulo

Typically hundreds of different chemical products stored in small flasks which cannot accommodate labels large enough to bear all information required by the Globally Harmonised System of Classification, Labelling and Packaging of Chemicals (GHS) are used in academic laboratories. To overcome this restriction Brazilian legislation permits communication of the dangers of chemical products to trained laboratory workers/students by alternative means. Here we describe an alternative label system, developed by the German Social Accident Insurance (DGUV), which allows hazard communication to trained workers/students via a labelling system, using pictograms and highly condensed hazard statements to alert about dangerous chemical products.

Nanocompósito de polpa de mamão e nanopartículas de quitosana para aplicação em embalagens

Nanocomposite materials have been incorporated into biopolymers, (e.g. hydroxypropyl methylcellulose), to improve their physical and chemical properties and enable them to be applied in food packaging, especially for their biodegradable and renewable properties. With this addition, fruit puree has been incorporated into the films to confer nutritional properties besides color and flavor. Chitosan is of interest in the packaging field since it is a biodegradable, bioabsorbable, antimicrobial agent. Furthermore, chitosan nanoparticles have been widely explored for their interesting properties and potential applications in food packaging. This work was divided into two stages: (1) chitosan nanoparticle synthesis; (2) addition of nanoparticles into HPMC and papaya puree films. Addition of chitosan nanoparticles to HPMC and papaya puree films improved film properties: mechanical, thermal and water vapor barrier. We have developed a novel nanomaterial with great potential for application in packaging to prolong the shelf life of food.

BIOFILMS BASED ON CANIHUA FLOUR (Chenopodium Pallidicaule): DESIGN AND CHARACTERIZATION

This work aims to (1) produce and characterize the flour obtained from two varieties of canihua, cupi and illpa-inia, and (2) evaluate the ability of these flours to form biofilms. The flours produced contain proteins, starches, lipids, organic substances containing phenol groups, and high percentages of unsaturated fatty acids. Films produced from the illpa variety presented lower water vapor permeability and larger Young’s modulus values than the films formed from the cupi variety. Both films were yellowish and displayed a high light blocking ability (as compared with polyethylene films), which can be attributed to the presence of phenolic compounds. Furthermore, they showed lesser solubility and water permeability than other polysaccharide films, which may be the result of the higher protein (12%–13.8%) and lipid (11%) contents in canihua flours, as well as the formation of a larger number of S–S bonds. On the other hand, these films presented a single vitreous transition temperature at low temperatures (< 0 °C), crystallization of the A and Vh types, and an additional diffraction peak at 2 = 7.5º, ascribed to the presence of essential fatty acids in canihua flour. Canihua flour can form films with adequate properties and shows promise for potential applications in food packaging, because it acts as a good barrier to incident ultraviolet light.

MICROESTRUTURA E PROPRIEDADES DE FILMES DE AMIDO-ÁLCOOL POLIVINÍLICO-ALGINATO ADICIONADOS DE ÓLEOS ESSENCIAIS DE COPAÍBA E CAPIM LIMÃO

AbstractFilms obtained by blends between starch and other polymers and films developed with the addition of an oil can show higher water vapor barriers and improved mechanical properties. Films with starch/PVOH/alginate were obtained by adding copaiba and lemongrass essential oils (EOs). Films without oil served as the control. The microstructure, water vapor permeability (PVA), mechanical properties, and antifungal activity were determined for the films. The effects of the addition of the EOs on the properties of the films were dependent of the concentration and type of oil. The films with 0.5% lemongrass EO were similar to the control films. These films showed a 2.02 × 10-12 g s-1Pa m-1 PVA, 11.43 MPa tensile stress, 13.23% elongation, and 247.95 MPa/mm resistance at perforation. The addition of 1% of copaiba EO increased the PVA from 0.5 × 10-12 to 12.1 × 10-12 g s-1 Pa m-1 and the diffusion coefficient from 0.17 × 10-8 to 7.15 × 10-8m2/day. Films with quantities of EOs displayed fissures and micropores; the control films developed micropores with smaller diameters than films with EOs. The addition of EOs did not change the resulting infrared spectrum of the films. The films with oil displayed a diminished development of the Fusarium sp. culture, and the film without EOs did not display notable differences in the development of the culture. The starch/PVOH/alginate films with 0.5% lemongrass EO were the most suited for the development of a packaging active system.

Elintarvikekelpoisten painovärien vertailu offsetpainatuksessa

Tässä diplomityössä tutkittiin kolmen eri painovärivalmistajan elintarvikekelpoisia arkkioffsetpainovärisarjoja ja verrattiin niitä keskenään. Tavoitteena oli löytää optimaalinen elintarvikekartonkipakkausten painamiseen soveltuva arkkioffsetpainoväri. Työn kirjallisessa osassa selvitettiin yleisesti offsetpainatusprosessia, painovärien koostumusta ja elintarvikekelpoisten painovärien eroavaisuutta verrattuna perinteisiin offsetpainoväreihin. Kirjallisuusosassa tuotiin esille myös niitä tekijöitä, joilla elintarvikekelpoisuus määritellään. Näistä yksi tärkeä osa-alue on migraatio-ongelmat, joka on lainsäädännön kannalta ajankohtainen. Kokeellista osaa varten koepainovärejä painettiin taivekartongille arkkioffsetpainokoneella. Painetuista arkeista tehtiin mittauksia, joissa käytettiin densitometrisia, kolorimetrisia, kromatografisia ja aistinvaraisia menetelmiä. Näillä pyrittiin tuomaan esille eroavaisuuksia tutkittavana olleiden painovärien välille. Koeajojen ja mittausten perusteella analysoitiin painatuksen laatua, painettavuutta, painovärien elintarvikekelpoisuutta ja kestävyyttä. Työn tulosten perusteella ei voida suoraan osoittaa, että jokin painovärisarja olisi toimivampi kuin toinen. Yksi johtopäätös olikin, että painovärien koostumusta ja painatusprosessia on mahdollista modifioida monella tavalla, jolloin voidaan parantaa joitakin painovärin ominaisuuksia. Yleisesti kokeet osoittivat, että perinteinen aistinvarainen tapa testata painovärin elintarvikekelpoisuutta on hyvin subjektiivinen ja antaa arveluttavia tuloksia. Koetuloksista oli kuitenkin havaittavissa, että uuden sukupolven vähemmän migraatiota aiheuttavat painovärit ovat elintarvikekelpoisempia kuin aikaisempien kehitysasteiden painovärisarjat.

Kartonkimateriaalien muotoutuvuus vuokien valmistuksessa

Diplomityön tavoitteena oli tutkia erilaisten elintarvikekartonkien muotoutuvuutta prässäämällä valmistettujen vuokien valmistuksessa. Kirjallisuusosassa käsiteltiin mm. kartongin muotoutuvuuteen vaikuttavia ominaisuuksia sekä lämpötilan ja kosteuden vaikutusta muotoutuvuuteen. Lisäksi kirjallisuusosassa käytiin läpi vuokien valmistusprosessi, jossa vuoka-aihiot valmistetaan stanssaamalla ja vuoat prässäämällä. Lopuksi on esitetty vuokien valmistuksessa kartongin muotoutuvuuteen vaikuttavia ajoparametrejä. Kokeellisessa osassa valmistettiin prässäämällä vuokia erilaisista kartonkimateriaaleista. Jokaiselle materiaalille etsittiin sopivat ajoparametrit erilaisissa kosteuspitoisuuksissa ja vertailtiin niiden muotoutuvuutta. Työ sisälsi myös kaksi laminointikoeajoa, jonka tuloksena saatuja materiaaleja verrattiin referenssi vuokakartonkiin. Vuokien todettiin muotoutuvan parhaiten kosteuden ollessa 7 – 9,4 % välillä. Työssä erottui kartongit, jotka muotoutuivat muita paremmin sekä kartongit, jotka muotoutuivat muita huonommin. Näiden muotoutuvuutta pyrittiin selvittämään mitattujen paperiteknisten ominaisuuksien avulla, mutta selvää yksittäistä selittävää ominaisuutta ei löytynyt. Parhaiten muotoutuvuutta kuvasivat kartonkien kuitukoostumukset. Laminoitujen rakenteiden todettiin muotoutuvan vuokakartonkia paremmin. Tähän vaikuttivat laminaattien korkeammat lujuus- ja venymäarvot.

Jätehuoltosuunnitelman laatiminen elektroniikka-alan yritykselle

Sähkö- ja elektroniikka-alan yritykset eivät yleensä kuormita merkittävästi ympäristöä, sillä teollisuudenalan suurimmat ympäristövaikutukset aiheutuvat alihankkijoiden ja komponenttivalmistajien toiminnasta. Yritysten oma toiminta perustuu pitkälti tuotekehitykseen ja tuotteiden loppukokoonpanoon valmiista komponenteista. Syntynyt jäte on tyypillisesti pääosin pakkausjätettä, metalleja, kaatopaikkajätettä ja vähäisessä määrin myös ongelmajätettä. Vähäisen ympäristökuormituksen johdosta yrityksiltä ei yleensä vaadita ympäristölupaa. Diplomityössä laadittiin jätehuoltosuunnitelma elektroniikka-alan yritykselle. Työ suoritettiin Kemppi Oy:n toimeksiannosta Lahdessa. Jätehuoltosuunnitelman noudattaminen parantaa yrityksen julkisuuskuvaa ja tuo kustannussäästöjä. Toimivan suunnitelman laatiminen vaatii kuitenkin aikaa ja muita resursseja. Jätehuollon toimivuus on tarkistettava säännöllisesti, etenkin silloin kun yrityksen toiminnan painopiste muuttuu. Käytännön osuudessa kartoitettiin edellisvuosien jätemäärät ja yrityksen jätehuollon tila. Jätehuoltosuunnitelman laatimiselle oli selkeä tarve, koska jätehuolto perustui osin kirjoittamattomiin sääntöihin ja vanhoihin tottumuksiin. Syntypaikkalajittelua tehostettiin lisäämällä jäteastioita ja -pisteitä jätteiden syntypaikoille. Lajittelua parannettiin myös laatimalla selkeät ohjeet ja kouluttamalla työntekijöitä.