Bücher von Sajid Maqsood

This book provides a comprehensive overview of recent developments to valorize fish waste as a source of useful products. In the first few chapters, an introductory section unearths global fish waste production, its detrimental effects and its role in the circular economy. The next section of the book discusses recent applications of fish waste and by-products utilization for the production of useful products such as fertilizers, biogas, biodiesel, fish sauce, enzymes and many more. This book will serve as an important source of recent research developments and applications of fish waste generated at different stages of fish processing. This book will also act as an important reference to the research group conducting research on fish and fish by-product utilization and valorization.

A deterioração causada pelas reacções químicas e microorganismos são a principal causa de perdas de qualidade do peixe e dos produtos da pesca durante o manuseamento, processamento e armazenamento. O desenvolvimento de odores rançosos e sabores desagradáveis, alterações de cor e textura, bem como a diminuição do valor nutricional do peixe, podem ser evitados através de aditivos naturais selectivos. Devido aos potenciais perigos para a saúde dos aditivos sintéticos actualmente utilizados, os aditivos naturais, especialmente os compostos polifenólicos, têm sido intensamente pesquisados como as alternativas seguras. Os polifenóis (PP) são os antioxidantes naturais predominantes em frutas, vegetais, bebidas (chá, vinho, sumos), plantas, algas e algumas ervas aromáticas e mostram a actividade antioxidante e antimicrobiana em diferentes peixes e produtos de peixe. A utilização de compostos polifenólicos também parece ser uma boa alternativa para o agente sulfito de retardamento da melanose em crustáceos. Os compostos fenólicos como auxiliar de processamento para a modificação textural de peixe picado e surimi também tem sido implementados com sucesso. Ficou provado que são os aditivos potenciais para evitar a deterioração da qualidade ou para melhorar a qualidade do peixe e dos produtos da pesca.

Il deterioramento causato da reazioni chimiche e microrganismi è la causa principale della perdita di qualità del pesce e dei prodotti ittici durante la manipolazione, la lavorazione e la conservazione. Lo sviluppo di odori rancidi e di sapori sgradevoli, le alterazioni del colore e della consistenza e la riduzione del valore nutrizionale del pesce possono essere evitati con additivi naturali selettivi. A causa dei potenziali rischi per la salute degli additivi sintetici attualmente utilizzati, gli additivi naturali, in particolare i composti polifenolici, sono stati intensamente ricercati come alternative sicure. I polifenoli (PP) sono antiossidanti naturali presenti in frutta, verdura, bevande (tè, vino, succhi), piante, alghe e alcune erbe e mostrano attività antiossidante e antimicrobica in diversi pesci e prodotti ittici. L'uso di composti polifenolici sembra anche essere una buona alternativa agli agenti solforanti per ritardare la melanosi nei crostacei. I composti fenolici sono stati utilizzati con successo anche come coadiuvanti tecnologici per modificare la struttura del macinato di pesce e del surimi. Si sono dimostrati potenziali additivi per prevenire il deterioramento della qualità o per migliorare la qualità del pesce e dei prodotti ittici.

El deterioro causado por las reacciones químicas y los microorganismos es la principal causa de pérdida de calidad del pescado y los productos pesqueros durante su manipulación, procesamiento y almacenamiento. El desarrollo de olores rancios y sabores desagradables, los cambios de color y textura, así como la disminución del valor nutricional del pescado pueden evitarse mediante aditivos naturales selectivos. Debido a los peligros potenciales para la salud de los aditivos sintéticos que se utilizan actualmente, los aditivos naturales, especialmente los compuestos polifenólicos, se han buscado intensamente como alternativas seguras. Los polifenoles (PP) son los antioxidantes naturales que prevalecen en las frutas, las verduras, las bebidas (té, vino, zumos), las plantas, las algas y algunas hierbas, y muestran la actividad antioxidante y antimicrobiana en diferentes pescados y productos de la pesca. El uso de compuestos polifenólicos también parece ser una buena alternativa al agente sulfitante para retardar la melanosis en los crustáceos. También se ha aplicado con éxito el uso de compuestos fenólicos como ayuda para la modificación de la textura de la carne picada de pescado y el surimi. Se ha demostrado que son los aditivos potenciales para prevenir el deterioro de la calidad o para mejorar la calidad del pescado y de los productos pesqueros.

Der durch chemische Reaktionen und Mikroorganismen verursachte Verderb ist die Hauptursache für Qualitätsverluste bei Fisch und Fischprodukten während der Handhabung, Verarbeitung und Lagerung. Die Entwicklung von ranzigem Geruch und unangenehmem Geschmack, die Veränderung von Farbe und Textur sowie die Verringerung des Nährwerts von Fisch können durch selektive natürliche Zusatzstoffe verhindert werden. Aufgrund der potenziellen Gesundheitsgefahren der derzeit verwendeten synthetischen Zusatzstoffe wurde intensiv nach natürlichen Zusatzstoffen, insbesondere Polyphenolverbindungen, als sichere Alternativen gesucht. Polyphenole (PP) sind natürliche Antioxidantien, die in Obst, Gemüse, Getränken (Tee, Wein, Säften), Pflanzen, Algen und einigen Kräutern vorkommen und in verschiedenen Fischen und Fischprodukten antioxidative und antimikrobielle Wirkung zeigen. Die Verwendung von polyphenolischen Verbindungen scheint auch eine gute Alternative zu Sulfitierungsmitteln zu sein, um die Melanose bei Krustentieren zu verzögern. Phenolische Verbindungen wurden auch erfolgreich als Verarbeitungshilfsmittel zur Veränderung der Textur von Fischhackfleisch und Surimi eingesetzt. Sie haben sich als potenzielle Zusatzstoffe erwiesen, um eine Qualitätsverschlechterung zu verhindern oder die Qualität von Fisch und Fischprodukten zu verbessern.

La détérioration causée par les réactions chimiques et les micro-organismes est la principale cause de perte de qualité du poisson et des produits de la pêche pendant la manipulation, la transformation et le stockage. Le développement d'odeurs rances et de saveurs désagréables, les changements de couleur et de texture ainsi que la diminution de la valeur nutritionnelle du poisson peuvent être évités par des additifs naturels sélectifs. En raison des risques potentiels pour la santé des additifs synthétiques actuellement utilisés, les additifs naturels, en particulier les composés polyphénoliques, ont fait l'objet de recherches intensives en tant qu'alternatives sûres. Les polyphénols (PP) sont des antioxydants naturels présents dans les fruits, les légumes, les boissons (thé, vin, jus), les plantes, les algues et certaines herbes et présentent une activité antioxydante et antimicrobienne dans différents poissons et produits de la pêche. L'utilisation de composés polyphénoliques semble également être une bonne alternative à l'agent sulfitant pour retarder la mélanose chez les crustacés. Les composés phénoliques ont également été utilisés avec succès comme auxiliaires de fabrication pour modifier la texture du hachis de poisson et du surimi. Ils se sont avérés être des additifs potentiels pour prévenir la détérioration de la qualité ou pour améliorer la qualité du poisson et des produits à base de poisson.

This book describes several emerging non-thermal processing techniques that can be specially employed for the dairy processing industry. The book narrates the benefits of using pulsed light, cold plasma, high pressure and ultrasonic during processing of various dairy products.

Lipid oxidation is one of the key problems associated with the loss of quality of seafood. In the seafood industry, lipid oxidation is a serious problem, not only because it produce rancid odors and flavors, decreases shelf life and alter texture and appearance of foods, but also because it can decrease the nutritional quality and safety of seafood. It is the process by which oxygen reacts with unsaturated lipids present in the foodstuff. In the presence of an initiator, polyunsaturated fatty acids can become oxidized and form alkyl radicals. When exposed to oxygen, the alkyl radicals rapidly form peroxyl radicals and these radicals can react with more lipids to produce hydroperoxides. As a lipid hydroperoxide decomposes, it forms numerous volatile compounds such as hexanal and propanal, which impact the sensory quality of foods. Lipid oxidation in seafood can be mediated by enzymes like lipoxygenase, cycloxygenase and haem protein like haemoglobin and myoglobin. Oxidation of lipids is accentuated in the immediate post-slaughter period, during handling, processing, storage and cooking. This process leads to discoloration, off-odor and off-flavor development.

Spoilage caused by the chemical reactions and microorganisms are principal cause of quality losses of fish and fish products during handling, processing and storage. Development of rancid odours and unpleasant flavours, changes of colour and texture as well as lowering nutritional value in fish can be prevented by selective natural additives. Due to the potential health hazards of synthetic additives currently used, natural additives, especially polyphenolic compounds have been intensively searched as the safe alternatives. Polyphenols (PP) are the natural antioxidants prevalent in fruits, vegetables, beverages (tea, wine, juices), plants, seaweeds and some herbs and show the antioxidative and antimicrobial activity in different fish and fish products. The use of polyphenolic compounds also appears to be a good alternative for sulphiting agent for retardation of melanosis in crustaceans. Phenolic compounds as the processing aid for textural modification of fish mince and surimi has also been successfully implemented. They have been proved to be the potential additives to prevent the quality deterioration or to improve the quality of fish and fish products.