Thesis (M.Soc.Sc.)--University of Hong Kong, 1990. / Also available in print.

Thesis (Ph.D.)--RAND Graduate School, 2007. / Title taken from PDF title screen (viewed October 18, 2007). Includes bibliographical references.

Thesis (Ph.D.)--York University, 2003. Graduate Programme in Administration. / Typescript. Includes bibliographical references (180-193). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ99259

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references. Also available in electronic version.

Authenticity issues and fraudulent practices regarding animal products are affecting consumer confidence. Verifying the description, composition, processing or origin of foods can be challenging. To explore British and Kurdish consumers’ perceptions of kebab meat products, focus groups and questionnaire surveys were applied. About 40% of participants in the UK tend to purchase fewer processed meats after the European horsemeat scandal. Issues raised by participants indicated their concerns about the declaration of species, meat content, and other ingredients incorporated in kebab and other meat products. Lack of consumer trust has been linked to authenticity issues. Reactions towards the addition of fat-replacing inulin were positive by more than half of respondents. A further study aimed to investigate the effect of commercial inulin (CI) and Jerusalem artichoke (JA) tubers as fat replacers on the eating quality and overall acceptability of kebabs. Inulin flour prepared from JA by a simple protocol presented advantages with about 10% higher cooking yield and overall acceptability when compared with CI. Levels of inulin as low as 0.5% were detected in meat products using enzymatic assay, which could be relevant to detect additives and enforce labelling requirements. The authenticity (origin and species) was investigated in fish samples from commercial markets in Erbil, Kurdistan Region of Iraq (KRI). The declared fish species was checked using DNA barcoding with Cytochrome b region. A 10 % rate of mislabelling occurred only for wild common carp (Cyprinus carpio), with 9 out of 12 discovered to be the related species goldfish (Carassius auratus), which was deemed to be accidental rather than deliberate fraud. Such occurrences were from street markets and fishmongers, while none were from supermarkets. Wild and farmed common carp samples were not discriminated by DNA barcoding. Further fingerprinting using compositional profile and nearinfrared spectroscopy (NIRS) together with chemometric analysis aimed to predict composition and discriminate between wild and farmed common carp and species identity. NIRS-predictions of composition and some macrominerals of fish have a strong correlation with the references. NIRS with chemometric analysis is promising, but were not satisfactorily accurate for micro-minerals. Even with no clear solution from principal component analysis (PCA), NIRS-PCA may contribute to discriminating sample groups, but not for authentication when used alone. Having reliable techniques for authentication of food of animal origin may discourage deliberate replacement in retail, wholesale and international trade, and may contribute to reductions in food mislabelling, therefore protecting consumers from fraudulent practices.

O leite é um alimento sujeito à fraudes. As mais frequentes são a adição de água, reconstituintes, conservantes e neutralizantes. Apesar da legislação determinar a pesquisa diária dessas substâncias, a avaliação do leite pelas indústrias geralmente é realizada apenas por análises físico-químicas genéricas como densidade e crioscopia. Contudo, essas fraudes muitas vezes são calculadas para impedir sua identificação por provas de rotina não específicas. O objetivo desse trabalho foi pesquisar a ocorrência de fraudes, resíduos de antibióticos e irregularidades físico-químicas e microbiológicas em leite pasteurizado, bem como avaliar a capacidade de detecção de adulterações e a suficiência das provas oficiais específicas e inespecíficas na identificação da adição de reconstituintes, conservantes e neutralizantes. Foram avaliadas 100 amostras de leite pasteurizado, produzido no Paraná, para a presença de reconstituintes, conservantes, neutralizantes e antibióticos e demais parâmetros físico-químicos e microbiológicos determinados pela legislação. Em outro experimento, a capacidade de detecção das provas oficiais para pesquisa de sacarose, cloretos, amido, formaldeído, cloro, hipoclorito, peróxido de hidrogênio e neutralizantes da acidez foi avaliada utilizando-se de amostras adulteradas em laboratório. Foram avaliados adicionalmente testes não oficiais para avaliar a presença de inibidores do crescimento microbiano e o efeito inibidor de algumas substâncias conservantes e neutralizantes sobre a microbiota do leite cru. Os resultados mostraram que das 100 amostras de leite pasteurizado, 51% apresentaram problemas, das quais 25% estavam fora dos padrões nas análises físico-químicas e 10% nas análises microbiológicas, 14% apresentaram resíduos de antibióticos e a adição de reconstituintes foi detectada em 13% das amostras. Observou-se que a avaliação do leite apenas por análises físico-químicas de rotina, como densidade e crioscopia não é suficiente para identificar fraudes por adição de água e reconstituintes. As provas para a pesquisa específica de substâncias reconstituintes apresentaram boa capacidade de detecção, assim como a prova para pesquisa de formaldeído. A adição de sacarose em amostras adulteradas no laboratório elevou a porcentagem de lactose detectada por equipamentos que utilizam infravermelho e ultrassom, demonstrando que estes equipamentos não quantificam especificamente a lactose. Quanto às amostras adicionadas de conservantes e neutralizantes no laboratório, a prova inespecífica da cultura de iogurte foi capaz de detectar a inibição de crescimento nas amostras adicionadas de formaldeído, peróxido de hidrogênio, hipoclorito e hidróxido de sódio, apresentando resultados próximos aos das provas oficiais para a pesquisa dessas substâncias. A adição de formaldeído, peróxido de hidrogênio e hipoclorito promoveu reduções significativas nas contagens de micro-organismos aeróbios mesófilos no leite cru adulterado no laboratório. o entanto, não foi possível detectar peróxido de hidrogênio e compostos clorados após 24 horas de refrigeração, provavelmente em consequência da degradação e /ou inativação dessas substâncias no leite. A prova para a pesquisa de neutralizantes da acidez detecta a substância apenas quando a alcalinização é excessiva. A neutralização equilibrada do ácido lático resulta na anulação da capacidade de detecção da prova. A pesquisa de inibidores microbianos, neutralizantes e reconstituintes é obrigatória apenas para leite cru, porém, a presença de grande parcela de amostras positivas para reconstituintes e antimicrobianos no leite pasteurizado demonstra falhas no controle de qualidade e pode indicar a prática de adulteração do leite também pela indústria. / Milk is one of the major targets for fraud. The most frequent are addition of water, restoratives, preservatives and neutralizers. Although legislation determines the daily survey of these substances by specific tests, milk evaluation by industries is usually performed only by generic physicochemical tests as density and freezing point. However, these adulterations are often calculated to prevent their identification by these routine non specific tests. The aim of this study was to investigate the occurrence of fraud, antibiotic residues and irregularities in physico-chemical and microbiological parameters in pasteurized milk produced in northern Paraná, as well as to evaluate the ability of adulteration detection by official tests to identify the addition of restoratives, preservatives and neutralizers in milk. An assessement was performed in 100 pasteurized milk samples to evaluate the presence of restoratives, preservatives, antibiotics and neutralizers and other physico-chemical and microbiological tests determined by legislation. In a second experiment, the detection ability of official tests for the research of sucrose, chloride, starch, formaldehyde, chlorine, hypochlorite, hydrogen peroxide and neutralizers was evaluated using samples adultered in laboratory. Additionally, unofficial tests to evaluate the presence of inhibitors of microbial growth and the inhibitory effect of some preservative and neutralizers substances on the biota of raw milk were performed. Results show that of the 100 samples of pasteurized milk evaluated, 51% had problems, from which 25% were outside parameters for physicochemical analyzes, 10% for microbiological analyzes, 14% were positive for the presence of antibiotic and in 13% adulteration by restoratives were detected. It was observed that milk evaluation only by physico-chemical routine analyzes, such as density and cryoscopy is not sufficient to identify fraud by water and restoratives addition. Specific tets for restoratives detection exhibit good detection potentials, as well as the test for formaldehyde. . The addition of sugar altered quantification of lactose detected by equipments tha use infrared and ultrasound, demonstrating that these do not detect lactose exclusively. Regarding samples added with preservatives and neutralizers substances in laboratory, the yogurt culture test was able to detect microbial grouth inhibition in samples added with formaldehyde, hydrogen peroxide, hypochlorite and sodium hydroxide. Presenting resluts similar to the official tests. The addition of formaldehyde, hydrogen peroxide and hypochlorite promoted significant reductions in the counts of mesophilic aerobic micro-organisms in raw milk adulterated in laboratory. However it was not possible to detect hydrogen peroxide and clhorated compounds after 24 hours of refrigeration, maybe due to its rapid degradation and / or inactivation of these substances in milk. Neutralizing substances detection can only dectect this substances when alcalinization is excessive. The balanced neutralization of latic acid results on the anulment of detection ability of the test. The research of preservatives, neutralizers and restoratives is not required for pasteurized milk, only for raw milk. The presence of large numbers of samples positive for these substances demonstrates flaws in quality control of raw milk or occurrence of milk adulteration by the industry itself.

Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-06-28T12:20:13Z No. of bitstreams: 1 NataliaCM_DISSERT.pdf: 509724 bytes, checksum: 9edc7be828cda1f52ff39d0c626e3000 (MD5) / Made available in DSpace on 2017-06-28T12:20:13Z (GMT). No. of bitstreams: 1 NataliaCM_DISSERT.pdf: 509724 bytes, checksum: 9edc7be828cda1f52ff39d0c626e3000 (MD5) Previous issue date: 2017-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Artisanal cheeses participate in the socio-cultural identity of people and deserve recognition. Like many artisanally produced cheeses, it is common to produce coalho and butter cheeses from raw milk. For this reason, it is essential that the raw material from dairies is of good quality to minimize risks to consumers. Thus, this study aimed to evaluate the quality of milk in artisanal cheese factories in Rio Grande do Norte, Brazil. Fifty samples of milk in nine artisanal cheese factories were collected from areas that stand out in dairy production in the state. These samples underwent microbiological (viable strict and facultative mesophilic bacteria, total and thermotolerant coliforms, Salmonella sp., and Staphylococcus aureus) and physical-chemical analysis (titratable acidity in Dornic degrees, density, cryoscopy, stability to alizarol, and percentages of protein, lactose, and fat contents), and antibiotic residue and recurrent fraud in milk were conducted. All samples exceeded the limit established by law for mesophilic bacteria counting; Salmonella spp. was found in one sample. Given this contamination, the acidity of 76% of the samples was higher than allowed by the legislation. Regarding fat and protein parameters, 14% and 10% of the samples were below the required values by the legislation, respectively. Furthermore, there was fraud by adding water in 24% of samples. Chlorides were found in 16% and antimicrobial residues in 46% of samples. Therefore, the quality of the milk used in informal artisanal cheese making in the state of Rio Grande do Norte is poor and may pose a risk to consumers, with the loss of quality of coalho and butter cheeses / Os queijos artesanais participam da identidade sociocultural do povo e merecem valorização. Como muitos queijos produzidos de forma artesanal, é comum a fabricação dos queijos de coalho e de manteiga com leite cru. Por isso, é fundamental que a matéria-prima das queijarias apresente boa qualidade, a fim de minimizar riscos aos consumidores. Dessa forma, objetivou-se avaliar a qualidade do leite em queijarias artesanais do Rio Grande do Norte, Brasil. Foram coletadas cinquenta amostras de leite de nove queijarias informais de regiões que se destacam como bacias leiteiras no Estado. As amostras foram submetidas às análises microbiológicas (microrganismos mesófilos estritos e facultativos viáveis, coliformes totais, termotolerantes, Salmonella spp. e Staphylococcus aureus), físico-químicas (acidez titulável em graus Dornic, densidade, índice crioscópico, estabilidade ao alizarol, porcentagens de proteína, lactose e gordura), residuais e pesquisa de fraudes recorrentes em leite. Todas as amostras ultrapassaram o limite estabelecido pela legislação para contagem de microrganismos mesófilos; houve presença de Salmonella spp. em uma amostra. Dada esta contaminação, a acidez de 76% das amostras estava acima do permitido pela legislação. Quanto aos parâmetros de gordura e proteína, 14% e 10% das amostras estavam abaixo dos valores exigidos pela legislação, respectivamente. Além disso, houve fraude por adição de água em 24% das amostras. Foram encontrados cloretos em 16% e resíduos de antimicrobianos em 46% das amostras. Portanto, a qualidade do leite usado na fabricação informal de queijo artesanal no estado do Rio Grande do Norte é pobre, podendo representar um risco para o consumidor, com o comprometimento da qualidade dos queijos de coalho e de manteiga / 2017-06-28

Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-06-28T13:32:56Z No. of bitstreams: 1 LyzandraLAL_DISSERT.pdf: 1553694 bytes, checksum: 3b2dce61aa34ba06fdc0df889642bc15 (MD5) / Made available in DSpace on 2017-06-28T13:32:56Z (GMT). No. of bitstreams: 1 LyzandraLAL_DISSERT.pdf: 1553694 bytes, checksum: 3b2dce61aa34ba06fdc0df889642bc15 (MD5) Previous issue date: 2017-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Considering the abusive use of humectant agents in frozen seafood processing, and a possible relationship between the pH parameter and the phosphate food grade additive, the objective of the present study was to evaluate if there is a correlation between the pH of the tuna meat and different concentrations and time of contact of food additive phosphate. The tuna fillets (average of 225 g) were immersed in cold solutions (5°C) of sodium tripolyphosphate (STPP) and phosphates blend (concentrations) at concentrations of 3, 5 and 10% (fillet:solution ratio of 1: 1; w:v) at 30, 60 and 120 minutes. Water was used as the control group. After immersion, the samples were drained, weighed (yield calculation), frozen in ultrafreezer (-35ºC for 24 h) and stored (-35ºC) for 15 days. After this period, the samples were thawed (5°C, 24 hours), drained for 5 minutes, and weighed (yield calculation). After thawing, samples were grilled (200°C for 3 minutes on each side) and weighed (yield calculation). Samples were withdrawn after each step (immersion, thawing and cooking) and submitted to pH, phosphate (P2O5) moisture and protein analysis. The yield (gain and loss weight) was determined by the weight of the samples before and after the treatments (immersion, thawing and cooking). All food additives used in the present study (STPP and Blend) demonstrated their efficacy in water retention after immersion, thawing and cooking. There was a gradual increase in moisture content (after immersion in solutions of STPP and Blend), and a consequent increase in moisture/protein ratio suggesting a new parameter to be considered as indicative use of humectant agents in seafood. There was a gradual increase in pH and residual phosphate (P2O5) in all treatments, and still remained below the limits established by national (pH) and international (P2O5) legislation. A linear correlation was observed between pH and P2O5 values, which may become a parameter to be considered as indicative use of humectant agents (phosphates) in seafood. From the results of experiments, we suggest a critical review on the current issue, and those possible changes can be evaluated in the official parameters as indicators of abusive use of the phosphate additive in seafood and to combat economic fraud in the frozen products. It should be emphasized that these suggestions should be the focus of the collaborative study for its validation / Considerando o uso abusivo de agentes umectantes no processamento de pescado congelado, e uma possível relação entre o parâmetro pH e o aditivo fosfato, o objetivo do presente estudo foi avaliar se existe correlação entre o pH da carne do atum e diferentes concentrações e tempo de contato com o aditivo alimentar fosfato. Os filés de atum (média de 225 g) foram imersos em soluções refrigeradas (5°C) de tripolifosfato de sódio (TPF) e mistura de fosfato (blend) nas concentrações 3, 5 e 10% (proporção filé:solução de 1:1; p:v), por 30, 60 e 120 minutos. Como grupo controle utilizou-se água. Após a imersão, as amostras foram drenadas, pesadas (cálculo de rendimento), congeladas em ultrafreezer (-35ºC por 24 h) e armazenadas (-35ºC) por 15 dias. Após esse período, as amostras foram descongeladas (5°C, 24 horas), drenadas por 5 minutos, pesadas (cálculo de rendimento). Após o descongelamento, as amostras foram grelhadas (200ºC por 3 minutos em cada lado) e pesadas (cálculo do rendimento). Amostras foram retiradas após cada etapa (imersão, descongelamento e cocção) e submetidas às análises de pH, fosfato (P2O5), umidade e proteína. O rendimento (ganho/perda de peso) foi determinado pelo peso das amostras antes e após os tratamentos (imersão, descongelamento e cocção). Todos os aditivos alimentares utilizados no presente estudo (TPF e Blend) demonstraram sua eficácia na retenção de água após imersão, descongelamento e cocção. Observou-se um aumento gradual dos teores de umidade (após imersão em soluções de TPF e Blend), e consequente aumento na relação umidade/proteína que sugere um novo parâmetro a ser considerado como indicativo uso de agentes umectantes no pescado. Observou-se um aumento gradual do pH e do fosfato residual (P2O5) em todos os tratamentos, e ainda permaneceram abaixo dos limites estabelecidos pela legislação nacional (pH) e internacional (P2O5). Observou-se correlação linear entre os valores de pH e fosfato (P2O5) o qual pode se tornar um parâmetro a ser considerado como indicativo uso de agentes umectantes (fosfato) no pescado. A partir dos resultados dos experimentos, sugerimos uma revisão crítica sobre o tema, e que possíveis mudanças possam ser avaliadas nos parâmetros oficiais como indicadores de uso abusivo do aditivo fosfato em pescado e combater uma fraude econômica nos produtos congelados. Ressalta-se que essas sugestões devem ser o foco do estudo colaborativo para sua validação / 2017-06-28

Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-08-31T22:37:45Z No. of bitstreams: 1 LucasOSR_DISSERT.pdf: 2617988 bytes, checksum: 74015a9ee8413de24f14987804728470 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-09-06T15:19:40Z (GMT) No. of bitstreams: 1 LucasOSR_DISSERT.pdf: 2617988 bytes, checksum: 74015a9ee8413de24f14987804728470 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-09-06T15:22:42Z (GMT) No. of bitstreams: 1 LucasOSR_DISSERT.pdf: 2617988 bytes, checksum: 74015a9ee8413de24f14987804728470 (MD5) / Made available in DSpace on 2017-09-06T15:22:49Z (GMT). No. of bitstreams: 1 LucasOSR_DISSERT.pdf: 2617988 bytes, checksum: 74015a9ee8413de24f14987804728470 (MD5) Previous issue date: 2015-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Due to the high perishability of seafood, one of the main industry concerns is to improve conservation technologies, reaching a final product of good quality. Among the various methods used, it highlights the glazing process after freezing, which provides greater stability and shelf life for the product. On the other hand, some abuses have been reported regarding the water excess in glazed products, characterized as economic fraud. In this context, the aim of this study was toevaluate the effectiveness of official methods to quantify the glazing percentage in frozenwhite Pacific shrimp (Litopenaeus vannamei) samples, with different glazing percentages. Based on the obtained resultsasuggestion ofa new simpler and more efficient methodologyis a goal. Samples of peeled shrimp were subjected to glazing process (15%, 30%, 40%, 50% and 60%). The glazingpercentage was quantified based on methodologies of INMETRO, MAPA, CODEX, AOAC/NIST and through the proposal suggested in thiswork. The official methods were inefficient in quantifying the glazing percentage, especially with regard to samples containing high glazing percentages. The methodology proposed results were closer to the values of the glazing percentage of frozen shrimpsamples, confirming that the methodology can be an alternative to be used by the inspectors, after collaborative study validation of the methodology / Devido à alta perecibilidade do pescado, uma das principais preocupações da indústria é aperfeiçoar as tecnologias de conservação, alcançando um produto final de boa qualidade. Dentre os vários métodos utilizados se destaca o glaciamento após o congelamento, que proporciona maior estabilidade e vida de prateleira ao produto. Em contrapartida alguns abusos têm sido relatados no tocante ao excesso de água nos produtos glaciados, caracterizando-se como fraude econômica. Nesse contexto, o objetivo do presente estudo foi avaliar a eficiência dos métodos oficiais para quantificação do percentual de glaciamento em amostras de camarão branco do pacífico(Litopenaeus vannamei)congelado, com base nos resultados obtidos sugerir uma nova metodologia simples e mais eficiente.Amostras de camarão descascado foram submetidas a processo de glaciamento (15%, 30%, 40%, 50%, e 60%).O percentual de glaciamento foi quantificado com base nas metodologias do INMETRO, MAPA, CODEX, AOAC/NIST e através da proposta sugerida no trabalho.As metodologias oficiais foram ineficientes na quantificação do percentual de glaciamento, principalmente no que tange às amostras contendo altos percentuais de glaciamento. Os resultados da metodologia proposta se aproximaram mais aos valores do percentual de glaciamento das amostras de camarão congelado, confirmando que a metodologia pode ser uma alternativa a ser utilizada pelos órgãos fiscalizadores, após estudo colaborativo de validação da metodologia / 2017-08-31

>Magister Scientiae - MSc / The recent years have seen an increase in the number of users accessing online services using communication devices such as computers, mobile phones and cards based credentials such as credit cards. This has prompted most governments and business organizations to change the way they do business and manage their identity information. The coming of the online services has however made most Internet users vulnerable to identity fraud and theft. This has resulted in a subsequent increase in the number of reported cases of identity theft and fraud, which is on the increase and costing the global industry excessive amounts. Today with more powerful and effective technologies such as artificial intelligence, wireless communication, mobile storage devices and biometrics, it should be possible to come up with a more effective multi-modal authentication system to help reduce the cases of identity fraud and theft. A multi-modal digital identity management system is proposed as a solution for managing digital identity information in an effort to reduce the cases of identity fraud and theft seen on most online services today. The proposed system thus uses technologies such as artificial intelligence and biometrics on the current unsecured networks to maintain the security and privacy of users and service providers in a transparent, reliable and efficient way. In order to be authenticated in the proposed multi-modal authentication system, a user is required to submit more than one credential attribute. An artificial intelligent technology is used to implement a technique of information fusion to combine the user’s credential attributes for optimum recognition. The information fusion engine is then used to implement the required multi-modal authentication system.