Neste trabalho avaliou-se o comportamento reológico dos 11 molhos comerciais para salada, tratados pelo processo de irradiação por raios gama, nas doses: 3 kGy e 5 kGy. Essa avaliação foi realizada por meio de reogramas traçados por medidas de viscosidade e tensão de cisalhamento por taxa de cisalhamento. Parâmetros matemáticos, obtidos destas medidas, também contribuiram para a conclusão do comportamento apresentado e do melhor modelo matemático aplicável a cada molho. As medidas foram realizadas em um viscosímetro de Brookfield modelo LVDV III. O banho térmico Neslab foi empregado para manter a tempertura ambiente durante toda a análise. Realizou-se o protocolo de estudo em duas fases. Na fase 1, a avaliação ocorreu logo após as amostras terem sido irradiadas, as quais se encontravam próximas a suas datas de fabricação. Na fase 2 as amostras foram reavalidas após um período de armazenamento, próximo a data de expiração de suas validades. Paralelamente realizou-se medida de pH para avaliar sua estabilidade diante dos tratamentos e análises sensoriais, de dois dos onze molhos estudados, a fim de verificar a aceitação desses diante da irradiação. O comportamento pseudoplástico foi confirmado para todos os molhos através do modelo matemático, da lei da potência, que melhor se aplica a este, nas duas fases das análises. A irradiação, nas doses absorvidas estudadas, não influênciou nesse comportamento. Os resultados da análise sensorial indicaram boa aceitação dos molhos irradiados, pelos provadores. / This study evaluated the rheological behavior of 11 salad dressings ready to eat, processed by gamma irradiation, at doses: 3 kGy and 5 kGy. This assessment was made by rheograms traced by measurements of viscosity and shear stress by shear rate. Mathematical parameters obtained from these measures also contributed to the conclusion of the behavior exhibited and for choosing the best mathematical model applicable to them. The measurements were performed on a Brookfield viscometer Model LVDV - III. The Neslab thermal bath was used to maintain ambient temperature during the whole analysis. This study protocol was done in two stages. In step 1, the evaluation was performed soon after the samples have been irradiated when these were close to their dates of manufacture. In phase 2 the samples were reassessed after a period of storage, near the expiration date of their validity. Simultaneously pH measurement was performed to evaluate their stability in the face of treatment and sensory analyzes of two salad dressings were studied, in order to verify the acceptance of these when submitted to irradiation. The shear-thinning behavior was confirmed for all dressings through the mathematical model, the power law, that best model apply to this, in both phases. The irradiation at the absorbed doses studied did not influence this behavior. The results of sensory evaluation indicated good acceptance of irradiated sauces for the tasters.

Neste trabalho avaliou-se o comportamento reológico dos 11 molhos comerciais para salada, tratados pelo processo de irradiação por raios gama, nas doses: 3 kGy e 5 kGy. Essa avaliação foi realizada por meio de reogramas traçados por medidas de viscosidade e tensão de cisalhamento por taxa de cisalhamento. Parâmetros matemáticos, obtidos destas medidas, também contribuiram para a conclusão do comportamento apresentado e do melhor modelo matemático aplicável a cada molho. As medidas foram realizadas em um viscosímetro de Brookfield modelo LVDV III. O banho térmico Neslab foi empregado para manter a tempertura ambiente durante toda a análise. Realizou-se o protocolo de estudo em duas fases. Na fase 1, a avaliação ocorreu logo após as amostras terem sido irradiadas, as quais se encontravam próximas a suas datas de fabricação. Na fase 2 as amostras foram reavalidas após um período de armazenamento, próximo a data de expiração de suas validades. Paralelamente realizou-se medida de pH para avaliar sua estabilidade diante dos tratamentos e análises sensoriais, de dois dos onze molhos estudados, a fim de verificar a aceitação desses diante da irradiação. O comportamento pseudoplástico foi confirmado para todos os molhos através do modelo matemático, da lei da potência, que melhor se aplica a este, nas duas fases das análises. A irradiação, nas doses absorvidas estudadas, não influênciou nesse comportamento. Os resultados da análise sensorial indicaram boa aceitação dos molhos irradiados, pelos provadores. / This study evaluated the rheological behavior of 11 salad dressings ready to eat, processed by gamma irradiation, at doses: 3 kGy and 5 kGy. This assessment was made by rheograms traced by measurements of viscosity and shear stress by shear rate. Mathematical parameters obtained from these measures also contributed to the conclusion of the behavior exhibited and for choosing the best mathematical model applicable to them. The measurements were performed on a Brookfield viscometer Model LVDV - III. The Neslab thermal bath was used to maintain ambient temperature during the whole analysis. This study protocol was done in two stages. In step 1, the evaluation was performed soon after the samples have been irradiated when these were close to their dates of manufacture. In phase 2 the samples were reassessed after a period of storage, near the expiration date of their validity. Simultaneously pH measurement was performed to evaluate their stability in the face of treatment and sensory analyzes of two salad dressings were studied, in order to verify the acceptance of these when submitted to irradiation. The shear-thinning behavior was confirmed for all dressings through the mathematical model, the power law, that best model apply to this, in both phases. The irradiation at the absorbed doses studied did not influence this behavior. The results of sensory evaluation indicated good acceptance of irradiated sauces for the tasters.

The effects of starter cultures on short- to medium-chain free fatty acid contents am sensory attributes of different batches of summer sausages were determined. The summer sausages were from range ram mutton, and formulated after grinding to contain 23% fat. Commercial starter cultures from different sources, including Micrococcus varians or Micrococcus species and Lactobacillus plantarum, commercial microbial lipase, an indigenous Micrococcus isolate or encapsulated lactic acid were used to prepare the summer sausages. Three batches were made, each batch receiving six different treatments. Three consumer panels evaluated the sausages for acceptability and a trained screened panel evaluated the products using the flavor profile test. Encapsulated lactic acid treatment significantly improved the sensory acceptability of the sausages. Presence of mutton flavor was not detected in indigenous Micrococcus isolate and L. plantarum treatment. Gas chromatography was used to quantify all short- to medium-chain fatty acids from the sausages. Common fatty acids, C6 through C12, were identified by retention data. Increased C6 and C8 levels due to addition of lipase were associated with increase in mutton and rancidity flavors of the product. The relationships among the level of major fatty acids and the sensory parameters were mostly negative.

Magistrinio darbo pavadinimas „Išrūgų sūrių gamybos ypatumų įtaka jų biologinei vertei“. Darbo vadovas: prof., dr. Dalia Sekmokienė. Lietuvos sveikatos mokslų universitetas, Veterinarijos akademija, Maisto saugos ir kokybės katedra. Tiriamasis darbas atliktas 2011 – 2014 metais. Magistro darbo apimtis: 54 puslapiai, 6 lentelės, 30 paveikslų, 2 priedai, 65 literatūros šaltiniai. Darbo tikslas: Atlikti išrūginių sūrių gamybos, kokybės, vartojimo ypatumų analizę. Tyrimo uždaviniai: 1. Literatūros apie išrūgų panaudojimą maisto pramonėje, jų poveikį sveikatai bei išrūgų sūrių technologijų bei asortimento apžvalga. 2. Išrūgų sūrių gamyba panaudojant aromatinėmis, antimikrobinėmis bei antioksidacinėmis savybėmis pasižyminčius augalus ar jų ekstraktus. 3. Atlikti pagamintų sūrių sudėties bei juslinę analizes. 4. Išanalizuoti, kaip pateikiama informacija Ricotta sūrių etiketėse pagal HN 119:2002 reikalavimus 5. Atlikti vartotojų apklausą apie išrūgų sūrių vartojimą. Darbo metu atrinkome labiausiai skoninėmis bei sveikatinančiomis savybėmis pasižyminčius augalus (ybiškę, medaus krūmą, saulėgrąžas, garšvą, krapus, petražoles) ir su jais pagaminome išrūgų sūrius.Išrūgų sūrių juslinis įvertinimas atliktas trimis būdais: juslinių savybių įvertinimas, aprašomosios – profilinės analizės sudarymas ir juslinio priimtinumo įvertinimas. Vertinant Ricotta išrūgų sūrius tyrimai parodė, kad skoniu, kvapu, išvaizda ir labai geru priimtinumu išsiskyrė Ricotta sūris su medaus krūmo arbata... [toliau žr. visą tekstą] / Title of master’s work – „The influence of whey cheese production pecularities on it‘s biological value“. Research advisor: prof., dr. Dalia Sekmokienė. Lithuanian University of Health Sciences, Veterinary Academy, Department of Food Safety and Quality. Veterinary Food Safety. Research work was carried out in 2011 – 2014. Paperwork volume – 54 pages, presented 6 tables, 30 pictures, 2 supplements, 65 used references in the list of references. Aim of the thesis: perform the analysis of whey cheese production, quality and consumption characteristics. Objectives of the study: 1. Review of the literature on the use of whey in the food industry and their impact on health, whey cheese technology and assortment. 2. Whey cheese production using plants and their extracts which are known to have aromatic, antimicrobial and antioxidant properties. 3. Perform the prepared cheese composition and sensory analysis. 4. Analyze how the information is presented on Ricotta cheese labels in compliance with HN 119:2002 requirements. 5. Conduct a consumer survey on the use of whey cheese. During the study the plants with the most flavouring and health providing features (gumbo, honey bush, sunflowers, goutweed, dill, parsley) were selected and used when producing whey cheese. Whey cheese sensory evaluation was carried out in the three ways: evaluation of sensory properties, a descriptive - profiled analysis, and evaluation of sensory acceptability. When evaluating the whey cheese, the study... [to full text]

Orientador: Lireny Aparecida Guaraldo Gonçalves / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-10T22:48:51Z (GMT). No. of bitstreams: 1 Becker-Almeida_DeniseFabianaSilvestre_D.pdf: 1952309 bytes, checksum: 3a74a72f3ab9269e8d8a904f486fb372 (MD5) Previous issue date: 2008 / Resumo: Os ácidos graxos trans (AGT) presentes na dieta são oriundos principalmente das gorduras parcialmente hidrogenadas e em menor quantidade dos óleos refinados, da carne e do leite de animais ruminantes. Estudos comprovam que o consumo de AGT ocasiona o aumento da lipoproteína de baixa densidade (LDL) em grau similar ao causado pelos ácidos graxos saturados e a diminuição da lipoproteína de alta densidade (HDL). Mediante a necessidade de substituir gorduras contendo AGT em alimentos por gorduras sem trans este trabalho teve como objetivo produzir e avaliar gorduras interesterificadas quimicamente partindo-se de misturas binárias contendo óleos líquidos de algodão e de soja com óleo de palma totalmente hidrogenado (PTH). Misturas com diferentes teores destas matérias-primas foram avaliadas quanto às propriedades físico-químicas, características microscópicas dos cristais e tendência de cristalização, antes e após a reação química. Frações de algodão/PTH e soja/PTH foram testadas em escala de bancada e reproduzidas em escala piloto até desodorização para aplicação alimentícia. O conteúdo de gordura sólida, a composição triacilglicerólica, o comportamento de fusão e cristalização, bem como a consistência instrumental foram os parâmetros que permitiram a seleção das frações para aplicação. A gordura de algodão/PTH (65/35 p/p) foi aplicada em bolo tipo inglês e a gordura de soja/PTH (65/35 p/p) na produção de margarina de mesa (80% de lipídios). Os produtos desenvolvidos com as gorduras low trans foram comparados com produtos elaborados com gordura parcialmente hidrogenada. As margarinas tiveram aplicação mais apropriada como shortenings e foram utilizadas na elaboração de bolo. As propriedades reológicas e a avaliação sensorial dos bolos foram comparadas e permitiram considerar que a consistência, o volume e o sabor dos bolos preparados com as gorduras low trans foram os atributos menos apreciados pelos consumidores. A substituição da gordura parcialmente hidrogenada por gorduras low trans promoveu a obtenção de produtos com diferença significativa (p£ 0,05) em relação à aceitação e não garantiu a mesma qualidade estabelecida pelos consumidores. Alterações na formulação, nas condições de processo e o uso de aditivos específicos são necessários para atender a demanda e as novas exigências do mercado / Abstract: Trans fatty acids (TFA) present in diet come mainly from the partially hydrogenated fats and a lower amount from the refined oils, meat and ruminant animals¿ milk. Some studies show that TFA consumption leads to an increase in low-density lipoprotein (LDL) as much as that caused by saturated fatty acids and decrease in high-density lipoprotein (HDL). Hence, this study aimed to produce and evaluate chemically interesterified fats based on binary blends containing cottonseed and soybean oils with fully hydrogenated palm oil (FHPO). Mixtures with different contents of these raw materials were evaluated before and after chemical reaction, regarding to their physical-chemical properties, microscopic characteristics and tendency to crystallization. Fractions of cottonseed/FHPO and soybean/FHPO were tested in laboratory and reproduced in pilot scale until desodorization for food application. The solid fat content, triacylglycerol composition, melting and crystallization behaviors and instrumental consistency were the parameters studied for selecting fractions for application. The cottonseed/FHPO fat (65/35 w/w) was used in plain cake and the soybean/FHPO fat (65/35 w/w) in table margarine (80% lipids). Low trans products were compared to the ones with partially hydrogenated fat. Margarines showed better properties for cake preparation since they were suitable shortenings. Rheological properties and sensory evaluation of the cakes were also compared and allowed to consider that the product consistency, volume and flavor of the cakes made with low trans fats were the attributes less appreciated by consumers. The replacement of partially hydrogenated fat by low trans fats led to achieve significant different products (p£ 0,05), but did not ensure the same quality established by consumers. Changes in formulation, in process conditions and the use of specific additives are necessary to attend the market demand and its new requirements / Doutorado / Doutor em Tecnologia de Alimentos

Les pyranoanthocyanes sont des pigments présents dans les vins rouges qui évoluent considérablement pendant la vinification et l’élevage. Ils contribuent à la stabilité de la couleur au cours du vieillissement. Ce sont aussi de bons marqueurs de l’oxydation d’un vin rouge. Cependant, leur impact sensoriel est encore mal connu. L’objectif de cette thèse est de mettre en évidence un possible impact gustatif des pyranoanthocyanes. Pour répondre à cette problématique, une stratégie de caractérisation, de purification et de quantification a été élaborée. La chromatographie de partage centrifuge (CPC) a été utilisée comme technique chromatographique principale pour fractionner des échantillons de vin rouge micro-oxygénés. Huit fractions de composition différente ont été collectées. La première fraction est composée essentiellement de pigments coumaroylés, la seconde fraction principalement de flavanol-pyranoanthocyanes. Les pigments de ces deux fractions ont été purifiés par CLHP préparative puis semi-préparative. L’analyse de la structure par résonnance magnétique nucléaire a permis la caractérisation de quatre nouveaux pigments. La quantification des différentes familles de pigments dans des vins micro-oxygénés ou avec des modalités variables de dioxyde de soufre a été réalisée par UCLHP-DAD-ESI-QToF. Les résultats ont montré une évolution de la contribution des familles de pigments en corrélation avec l’oxygène. En particulier, la corrélation de la concentration en hydroxyphényl-pyranoanthocyanes avec l’oxygène et le SO2 a été pour la première fois mise en évidence. Les quatre nouveaux pigments ont été quantifiés dans tous les vins étudiés. Ils ont montré le même schéma d’évolution que leurs familles de pigments respectives. Ce sont donc de bons marqueurs de l’oxydation d’un vin rouge. Les pigments des deux premières fractions issues de la CPC ont été solubilisés dans une solution modèle de vin et utilisés pour l’analyse sensorielle. La fraction 1 ne nous a pas permis de conclure quant à un possible impact sensoriel. Un test triangulaire construit autour de six concentrations croissantes a été mis en place pour la caractérisation de la fraction 2. Les dégustateurs ont perçu un impact sensoriel en bouche et décrivent de l’amertume et une sensation de rondeur. C’est un premier résultat significatif en faveur de la compréhension et de l’amélioration de la connaissance de l’impact gustatif des pyranoanthocyanes dans les vins rouges. / Pyranoanthocyanins are pigments occurring in red wines. They considerably evolve during winemaking and aging. They contribute to wine color stability during aging. They are also great markers of oxidation. However, data about their sensory impact are still scarce. In order to answer this dilemma, characterization, purification and quantification strategies have been developed. Centrifugal partition chromatography (CPC) has been used as the main chromatographic technique for micro-oxygenated red wine fractionation. Eight fractions with variable composition have been collected. The first fraction is mainly composed of coumaroylated pigments, and the second fraction mainly composed of pyranoanthocyanins-flavanols. Pigments from these fractions have been purified using preparative and semi-preparative HPLC. Nuclear magnetic resonance for structural analysis allowed characterizing four new pigments. The concentration of several groups of pigments has been evaluated in micro-oxygenated red wines of red wines with variable modalities of Sulphur dioxide, using UPLC-DAD-ESI-QToF. The results showed a correlation between the contribution of pigments and oxygen. More specifically, the correlation between the concentration in hydroxyphenyl-pyranoanthocyanins and oxygen and Sulphur dioxide has been highlighted for the first time. The four new pigments have been quantified in all wine samples. They showed the same trend than their respective groups of pigments. They can therefore be considered as good markers of oxidation.Pigments from the two first CPC fractions have been solubilized in a wine-like medium and used for sensory analysis. Fraction 1 did not allow concluding a possible sensory impact. A triangle test has been built using six increasing concentrations to evaluate the impact of fraction 2. The wine-tasters have perceived in-mouth impact and described bitterness and roundness. This is a very first significant result in favor of understanding and improving knowledge about gustative impact of pyranoanthocyanins in red wines.

Dans le vin rouge, les composés phénoliques sont souvent associés à la qualité du produit. Parmi eux, les anthocyanes sont responsables de la couleur du vin rouge et chaque cépage possède un génome spécifique déterminant le profil anthocyanique de chacun. Les pratiques culturales peuvent influencer l’accumulation de ces molécules dans la baie de raisin, tandis que les différentes techniques fermentaires peuvent modifier leur extraction. Les flavanols monomères, oligomères et polymères des pépins et des pellicules contribuent à l’amertume et l’astringence des vins. Pendant la vinification et l’élevage, ceux-ci réagissent avec les anthocyanes modifiant les propriétés du vin. De nombreuses publications concernant les caractéristiques sensorielles des flavanols ont été réalisées, alors que la contribution sensorielle des anthocyanes est encore mal connue. Cette thèse se décompose en deux parties. La première partie s’intéresse à l’étude de l’utilisation d’ozone gazeux comme technique pré-fermentaire sur les cépages rouges Nebbiolo et Barbera après récolte et pendant le passerillage. L’ozone est une technique innovante pour la réduction des contaminations microbiennes et la réduction du dioxyde de soufre. L’influence de cette technique sur les parois cellulaire des pellicules, sur l’extraction, la concentration en flavanols et en anthocyanes pendant la macération a été évaluée. L’étude montre que l’ozone possède un impact sur la macération des raisins, induisant une extraction plus importante des anthocyanes dans le Nebbiolo. En revanche, l’ozone n’influence ni les anthocyanes moléculaires, ni le profil variétal de chaque cépage. Pendant le passerillage, l’inverse a été étudié. L’extraction des anthocyanes dans le Nebbiolo est diminuée. A l’inverse, bien que moins d’anthocyanes soient retrouvées dans le raisin de Barbera, le traitement ne possède aucun impact sur l’extraction de celles-ci. Concernant les flavanols, l’extraction est moins influencée par le traitement à l’ozone. Des différences ont été retrouvées dans le cépage Nebbiolo. Les flavonols sont plus concentrés après le traitement avec l’ozone sur les raisins post-récolte, alors qu’ils diminuent pendant le passerillage. La modification causée sur la paroi cellulaire par l’ozone ainsi que la dureté des pellicules pourraient prédire l’extraction des anthocyanes et des flavanols, grâce à des analyses multi-variées. En conséquence, le traitement avec l’ozone doit être adapté en fonction du cépage et du produit final désiré. Dans la deuxième partie, les anthocyanes des raisins ont été extraites à partir des raisins et ces extraits ont été fractionnés en trois fractions, glucoside, acetyl-glucoside et cinnamoyl-glucoside, par Chromatographie de Partage Centrifuge (CPC) et CLHP (Chromatographie Liquide Haute Performance) préparative. L’évaluation de l’astringence a été réalisée par des analyses de précipitation protéique avec une protéine modèle BSA (Bovine Serum Albumin) et des protéines salivaires, les anthocyanes réagissant avec ces dernières. Les analyses sensorielles et l’évaluation de l’astringence ont été combinées. La concentration en anthocyane diminue après le traitement avec les protéines salivaires, dans l’extrait total et dans les fractions, en particulier les cinnamoyl-glucosides apparaissent comme les plus réactives avec les protéines salivaires. Les seuils de perception gustatifs ont été calculés avec la méthode “Best estimate threshold” dans le vin modèle. Les fractions acétyl-glucosides et cinnamoyl-glucosides, suivies de la fraction glucoside, possèdent des seuils de perception plus bas aux concentrations retrouvées dans les vins. Les descripteurs associés à ces fractions sont l’amertume et l’astringence. Ces résultats démontreraient que les anthocyanes apportent une contribution sensorielle dans la perception du vin en bouche, corrélée à l’acétylation des molécules. / In red wine, phenolic compounds are generally associated with the quality of products. Among them, anthocyanins extracted from skins are responsible for wine colour. The grapevine genomes determine the anthocyanins profiles, but several factors in the vineyard can influence their accumulation, as well as post-harvest techniques can modify their extraction during winemaking. Monomeric, oligomeric and polymeric flavanols from skins and seeds contribute to astringency and bitterness of wine and during winemaking and ageing complexes formation with anthocyanins modifies wine characteristics. Several publications are available to understand flavanols sensory characteristics, whereas anthocyanins role has not consensus in scientific literature. This PhD thesis is composed by two parts. The first part deal with the evaluation of the use of gaseous ozone as post-harvest technique in red wine grapes Nebbiolo and Barbera used on both fresh grape and during withering. Ozone treatment is an innovative technology proved to avoid mycobiota spoilage and preserving from the use of sulphur dioxide. Its influence on flavanol and anthocyanin contents and extractabilities during maceration was evaluated, considering skin cell wall modification. In fresh grape, ozone influenced skin maceration for both the varieties, leading to a higher anthocyanin extraction in Nebbiolo grapes and lower in Barbera. Ozone did not influence the final individual anthocyanin extractability, respecting the varietal anthocyanin fingerprint. During dehydration, opposite trend was found: in Nebbiolo reported no change in the content of total anthocyanins just after ozone-assisted dehydration, but their extraction yield was lower. On the contrary, although lower contents of anthocyanins were found in Barbera grapes no differences in final extractability was found. Regarding oligomeric and polymeric flavanols, their extractability was less affected by the ozone treatment. Only in Nebbiolo, both oligomeric and polymeric flavanol extraction was increased in fresh grape, whereas it is slightly decrease during dehydration. The ozone-induced modification of skin cell wall composition together with skin hardness parameters fitted well in multivariate models to predict anthocyanins, oligomeric flavanols and polymeric flavanols extraction. Therefore, the ozone treatment should be adapted depending on the variety and on the target wine. In the second part, grape anthocyanins were isolated depending on the acylation patterns, i.e. glucoside, acetyl-glucoside, and cinnamoyl-glucoside by a combination of centrifugal partition chromatography (CPC) and preparative-HPLC. Protein precipitation analyses to assess astringency and sensorial analysis were carried out. Anthocyanins reacted with both bovine serum albumine and salivary proteins, in different extent, since higher interaction between anthocyanins and salivary proteins was found with a significative reduction of total extract and fractions glucoside, acetyl-glucoside, and cinnamoyl-glucoside. The latter in particular is the more reactive to salivary proteins. Sensorial analysis was carried out as detection threshold test. Best estimated threshold (BET) of anthocyanins were resulted in wine-range scale, in particular acetyl-glucoside and cinnamoyl-glucoside BET are lower of glucoside threshold, and descriptors reported were astringency and bitterness. These results show that anthocyanins can be detected as in-mouth properties contributors, and the magnitude of their involvement is related to anthocyanins acylation.

Akamu is a lactic acid bacteria fermented cereal-based food that complements infant diets in most African countries. Uncontrolled fermentation increases the variability in quality and safety of akamu. This study was aimed at the controlled fermentation of akamu with selected lactic acid bacteria (LAB), investigation of the probiotic potential of the LAB and the effect of variation in production method on the product quality and sensory properties. PCR-DGGE analysis of traditional akamu samples revealed LAB community dominated by Lactobacillus fermentum, L. plantarum, L. delbrueckii subsp. bulgaricus and L. helveticus. Isolated yeasts were Candida tropicalis, C. albicans, Clavispora lusitaniae and Saccharomyces paradoxus. The isolated Lactobacillus plantarum strains (NGL5 and NGL7) fermented irradiated ground maize slurries and produced significant levels of lactic acid (>73 mmol L-1) and low pH ≤3.63 displaying inhibitory activity against Salmonella enterica serovar Enteritidis NCTC 5188, Escherichia coli 1077 (NCTC 11560), Bacillus cereus NCIMB 11925, Staphylococcus aureus NCTC 3750 and Listeria monocytogenes NCTC 7973 in MRS agar and E. coli 1077 in maize slurry fermentation. Viability of both strains of L. plantarum at pH 2 after 3 h was reduced from ≥8.26±0.05 to ≤4.94±0.49 Log10 CFU mL-1 while incubation in 0.3% bile allowed growth to 5.73±0.13 and 7.93±0.12 Log10 CFU mL-1 after 6 h for NGL5 and NGL7 respectively. Auto-aggregation of the L. plantarum strains at 37oC (≥25 after 5 h) correlated with adhesion to hydrocarbons (<15, 26, 33 and 64% for Hexane, Hexadecane, Ethyl acetate and Chloroform respectively). The strains failed to exhibit gelatinase or haemolytic activity but adhered to porcine mucin (OD403 nm ≥0.63 with viability ≥6.52 Log10 CFU mL-1) and Caco-2 cells (≥5.13 Log10 CFU mL-1). The ash, mineral (Ca, K, Mg, Na, S and Zn), IDF, SDFP and TDF content of the L. plantarum fermented ground maize slurries were significantly (p≤0.05) higher than that of the traditional akamu but the peak and final viscosities (139.5 and 68.5 cP respectively) were significantly (p≤0.05) the least. The aroma, appearance, colour, flavour and texture of the resultant porridges were liked moderately by 75% of the assessors. This study demonstrated that fermentation with the L. plantarum strains would contribute towards product safety and the L. plantarum strains possessed some probiotic potential that could be beneficial to the consumers particularly in those developing countries were the main staple foods are fermented cereals.

Ce travail de thèse porte sur le choix, l’appréciation et la consommation des légumes chez les enfants de 8 à 11 ans en situation naturelle de repas scolaire. Dans une première étape, nous nous sommes focalisés sur les sujets (i.e. enfants) en étudiant leurs connaissances lexicales et perceptives des légumes. Ainsi, nous avons mis en évidence que la carotte, la tomate et la salade sont les trois légumes les plus familiers chez l’enfant. Les connaissances lexicales des légumes évoluent avec l’âge et sont plus importantes chez les enfants ruraux que chez les urbains. Nous n’avons pas observé de lien entre les connaissances perceptives des enfants et leur âge, leur genre, leur lieu de vie ou encore leur possession d’un potager à la maison. Deux objets ont été sélectionnés à l’issue de la première étape : un légume très connu et apprécié -la carotte ; un légume moins connu et moins apprécié -le brocoli. Dans une seconde étape, nous avons étudié l’influence de la forme et du temps de cuisson de ces deux légumes sur le comportement alimentaire des enfants. Les résultats indiquent que la carotte est plus choisie, appréciée et consommée sous une forme familière et peu cuite. Les enfants préfèrent visuellement les fleurettes de brocoli de petite taille aux fleurettes de grosse taille. Le temps de cuisson n’a pas modifié l’appréciation et la consommation des brocolis. La troisième étape a porté sur une variable situationnelle : les intitulés de plats. Nous avons, d’une part, analysé les préférences des enfants pour des intitulés de plats, et d’autre part, étudié l’influence de deux types d’intitulés sur le choix et la consommation de nouvelles recettes de carotte et de brocoli. L’ajout d’un intitulé de plat précisant le nom du légume s’est révélé être un moyen efficace pour augmenter la probabilité de choix d’une nouvelle recette de légumes présentée conjointement à une recette familière. L’intitulé n’a pas eu d’influence, lorsque la nouvelle recette a été présentée conjointement à une alternative plus appréciée (i.e. le riz). Ces travaux soulignent l’importance de la familiarité de l’enfant avec le légume et avec sa forme culinaire : les enfants choisissent, apprécient et consomment plus un légume familier et sous une forme culinaire familière. De plus, les résultats ont montré que l’intitulé du plat participe au choix des enfants et soulignent l’importance des facteurs situationnels dans le comportement alimentaire. / This PhD project aims at understanding better choice, liking and consumption of vegetables in 8- to -11-years children in natural situation of a school meal. In a first step, we focused on subjects (i.e. children) and studied their visual and perceptual knowledge of vegetables. We showed that carrots, tomatoes and lettuce were the three most familiar vegetables in children. Lexical knowledge of vegetables increases with age and is more important in rural children than urban ones. We did not observe a link between perceptual knowledge and children’s characteristics (i.e. age, gender, living environment or the possession of a vegetable garden at home). In a second step, we manipulated the shape and the duration of cooking for two objects (i.e. vegetables) selected at the end of the first step (i.e. a well-known and appreciated vegetable: carrots; a less known and less appreciated vegetable: broccoli). We studied the influence of these factors on children’s food behavior. Results showed that arrows are more frequently chosen, appreciated and consumed with a familiar shape and when less cooked. Visually, children preferred the broccoli presented in small florets rather than the big ones. The duration of cooking did not influence choices, liking and consumption of broccoli. The third step dealt with the influence of a situational variable: food labels. Firstly, we examined children’s preferences for several food labels, and secondly we studied the influence of these labels on children’s choice and consumption of two new recipes of carrots and broccoli. Adding a food label referring to the name of the vegetable was an effective mean to increase the probability that children would choose a new vegetable dish provided that no other more appreciated alternative was presented simultaneously. This research underlined the importance of children’s familiarity with the vegetable and its culinary form in their acceptance: children choose, appreciate and consume much more a familiar vegetable with a familiar culinary form. Also, the results showed that the food label participate to children food choice and underlined the importance of situational factors in food behavior.

Lietuvoje prieskoninės arbatos tampa populiaresnės, dėl prieskonių ir žolių vis labiau atskleidžiamų teigiamų savybių žmogaus sveikatai. Tačiau jų pasirinkimas yra dar nedidelis. Tyrimo tikslas buvo sukurti kelias prieskoninių arbatų kompozicijas ir įvertinti jų juslines savybes bei antimikrobinį poveikį. Buvo sukurtos keturios arbatų kompozicijos: „Virškinimo arbata“, „Rytinė arbata“, „Vakarinė arbata“ ir „Afrodiziakas“. Arbatų kompozicijos buvo maišomos namų sąlygomis. Juslinės savybės vertintos taikant juslinės aprašomosios analizės metodus. Specialiai apmokyta 6 vertintojų grupė atrinko pagrindines arbatų kompozicijų savybes. Antimikrobinės arbatų kompozicijų savybės buvo įvertintos difuzijos į agarą metodu prieš Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium. Atlikta arbatų kompozicijų juslinė analizė parodė, kad skirtingos sudėties arbatos mėginiai skyrėsi instrumentiniu metodu įvertintos spalvos charakteristikomis. Juslinės skonio ir kvapo savybės priklausė nuo arbatos sudėties, ir nors visų arbatos mėginių skonis ir kvapas buvo gana intensyvūs, sodrūs, tačiau atskiri jaučiami skoniai ir kvapai priklausė nuo arbatos sudėties. Preliminarus priimtinumo vertinimas parodė, kad „Afrodiziako“ arbatos skonis ir kvapas vertintas kaip mažiau priimtini nei kitų arbatos mėginių, gal būt, todėl, kad jos skonis, kvapas bei pojūtis burnoje labiau priminė buljoną nei arbatą, o tai daugeliui vartotojų yra neįprasta. Priimtino vartotojams... [toliau žr. visą tekstą] / Spice tea is becoming more popular in Lithuania regarding spices and herbs growing disclosed positive characteristics to human health. However, their selection is still limited. The goal of the research was to create a few teas compositions of spices and evaluate the organoleptic characteristics and antimicrobial effect. There were created four tea compositions, "Digestive Tea", "Morning Tea", "Evening Tea" and "Aphrodisiac". Tea compositions were home-made. Organoleptic characteristics were tested using descriptive sensory analysis methods. Specially trained 6 assessors group has sorted main characteristics of the tea compositions. Antimicrobial compositions of tea were evaluated by the agar diffusion method against Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium. Analysed teas sensory compositions showed that differences were found in tea compositions characteristics based on instrumental colour analysis instrumental method. Sensory flavour and aroma characteristics were based on the tea composition, despite all tea samples – flavour and fragrance were quite intense, however separately felt flavours and fragrances were based on, composition of tea. Preliminary assessment of the acceptability showed that the "Aphrodisiac" tea flavour and aroma selected as less acceptable than other tea samples, perhaps because of its taste, aroma and mouth feel were more like as broth than tea, which is unusual for most of the users. To consumers... [to full text]