ABSTRACT
BACKGROUND: Microencapsulated yeasts are a novel alternative as a delivery matrix for microbiological starters. This technology aims to protect the active compounds from adverse environmental conditions and prolong their useful life and could also improve the conditions of the starters for cocoa fermentation. The present study established the effective dose to apply the microencapsulated yeast Pichia kudriavzevii as a microbiological starter of fermentation and biotechnological strategy for promoting the biochemical dynamics and sensory expression of the cocoa variety CCN-51. For this, 0.5%, 1%, 2%, and 3% of microencapsulated P. kudriavzevii yeast insolated from the artisanal fermentation process of cocoa was added to the cocoa mass to be fermented and studied on a laboratory scale. RESULTS: The partial least squares regression of fermentation was related in four quartiles, comprising the hedonic judgments of the sensory evaluation with the biochemical traits of the cocoa liquor, finding a high correlation between the physicochemical variables total phenols, percentage of insufficiently fermented grains, and percentage of total acidity, with a level of bitterness and defects found in liquors with the addition of 0.5% of microencapsulated starter. The treatments with the addition of 2% and 3% of the inoculum showed a high correlation between the variables pH, total anthocyanins, cocoa, fruity and floral aromas, sweet taste, and general aroma perception. CONCLUSION: The higher presence of volatile compounds such as 2,3-butanediol associated with cocoa aroma and 1-phenyl-2-ethanol and acetophenone associated with aromatic descriptors of fruity and floral series allowed establishment in 2% of microencapsulated P. kudriavzevii yeast, comprising the effective dose for promoting the biochemical dynamics of laboratory-scale fermentation and the development of cocoa, as well as the fruity and floral aromas of cocoa CCN-51 liquor. The microencapsulation is suitable for cocoa starters. © 2023 Society of Chemical Industry.
Subject(s)
Cacao , Cacao/chemistry , Fermentation , Saccharomyces cerevisiae/metabolism , Anthocyanins/metabolism , GenotypeABSTRACT
Resumen En los últimos años se ha reconocido el potencial de las bacterias ácido lácticas (BAL) como agentes bioconservantes de productos cárnicos, incluido el pescado, al reducir el deterioro microbiológico y químico. El objetivo de este trabajo fue determinar el efecto bioconservante de dos cepas de BAL y el tiempo de impregnación en la calidad microbiológica y química de filetes de tilapia. Se evaluaron dos tiempos de impregnación (1h y 2h) y las BAL Lactobacillus plantarum JCM 1149 y Lactobacillus acidophilus ATCC4356. Los filetes bioconservados (FB) se almacenaron a 5°C y se evaluaron los cambios en el recuento de BAL, mesófilos, psicrófilos y coliformes totales durante 30 días. Los recuentos en los FB fueron de 5.94 de Log UFC/g. de BAL, y <2.7 log UFC/g de coliformes y psicrófilos. Los filetes control presentaron recuentos de 1.2 log UFC/g de BAL mientras los coliformes totales y psicrófilos superaron el límite permitido para consumo humano luego de 10 días. Luego de 10 días. El tratamiento que mantuvo la calidad microbiológica y química de los FB por más tiempo fue L. plantarum con inmersión de una hora. Las BAL estudiadas mostraron un efecto inhibitorio de la microflora deteriorante del pescado y una reducción en la formación de nitrógeno volátil, siendo un método viable para la conservación del pescado.
Abstract In recent years, it has recognized the potential of lactic acid bacteria (LAB) as biopreservatives agents for meat products, including fish, by reducing the microbiological and chemical spoilage. The aim of this study was to determine the effect of two strains biopreservative LAB and impregnation time on the microbiological and chemical quality of tilapia fillets. Two impregnation time (1h and 2h) and two LAB (Lactobacillus plantarum JCM 1149 and Lactobacillus acidophilus ATCC4356 were evaluated. The biopreserved fillets (BF) were stored at 5 ° C and the changes of the LAB count, mesophilic, psychrophilic and total coliforms., were evaluated for 30 days. The microbiological analysis show for the BF 5.94 log CFU / g. of LAB and <2.7 log CFU / g of coliform and psychrophilic bacteria. The control Fillets showed 1.2 log CFU / g of LAB while the psychrophile and total coliforms exceeded the allowed limit for human consumption after 10 days. The treatment kept the microbiological and chemical quality of the BF longer was L. plantarum with one hour of impregnation. The LAB studied showed an inhibitory effect of the spoilage microflora of fish and a reduction in the formation of volatile nitrogen compounds, being a viable fish preservation method.
Resumo Nos últimos anos tem se reconhecido o potencial das bactérias ácido lácticas (BAL) como agentes bioconservantes de pro dutos carnicos, incluído o peixe ao diminuir o deterioro microbiológico e químico. O propósito deste estudo foi determinar o efeito bioconservante de duas cepas de BAL e a avaliação do tempo de impregnação requerido para obter uma boa qua lidade microbiológica e química de filetes de tilapia. Foram avaliados dois tempos de impregnação (1h e 2h) com as BAL Lactobacillus plantarum JMC 1149 e Lactobacillus acidophilus ATCC4356. Os filetes biopreservados (FB) foram estocados a 5oC e valoradas as modificações na contagem de microorganismos BAL, mesófilos, psicrófilos, coliformes totais durante 30 dias. As contagens microbianas nos FB foram de 5.94 de log UFC/g e <2.7 log UFC/g de coliformes e psicrofilos. Os filetes controle apresentaram valores de 1.2 log UFC/g de BAL, não entanto os coliformes totais e psicrófilos superaram o limite permitido para consumo humano após 10 dias de estocagem. O tratamento que manteve a qualidade microbiológica e química dos FB por maior tempo foi de imersão com Lactobacillus plantarum por uma hora. As BAL estudadas amostraram um efeito inibitório da microflora deteriorante dos peixes e uma redução na formação de nitrogênio volátil se apresentan do como um método viável para a preservação de filete de peixe
ABSTRACT
Filamentous fungi are microorganisms widely known for their diverse biochemical features. Fungi can efficiently invade a wide variety of substrates under operational conditions producing numerous bioproducts of interest, such as enzymes, organic acids, aromatic compounds and colorants. An additional interesting characteristic of some fungi is their safety classification for different uses, which guarantees that the bioproducts obtained from them do not contain any toxic component deleterious to humans. Rhizopus oryzae is among this group of fungi and is classified as a GRAS filamentous fungus, commonly used for production of some oriental traditional foods. It is mainly recognized as a good producer of lactic acid; however, its potential for other biotechnological processes is under study. This review analyzes and discusses the current scientific and technical contributions which may maximize the potential of R. oryzae as a producer of different compounds of industrial interest.
