Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Assunto da revista
País de afiliação
Intervalo de ano de publicação
1.
Molecules ; 25(3)2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012956

RESUMO

Bark of Norway spruce and Scots pine trees contain large amounts of condensed tannins. Tannins extracted with hot water could be used in different applications as they possess antioxidative and antimicrobial activities. The use of bark tannins as e.g., food preservatives calls for increases in our knowledge of their antioxidative activities when applied in foodstuffs. To assess the ability of bark tannins to prevent lipid oxidation, hot water extracts were evaluated in a liposome model. Isolated tannins were also applied in dry-cured, salty meat snacks either as liquid extracts or in dry-powder form. Consumer acceptance of the snacks was tested by a sensory evaluation panel where outlook, odor, taste, and structure of the snacks were evaluated and compared to a commercial product without tannin ingredients. Our results show that conifer bark tannin-rich extracts have high capacity to prevent lipid oxidation in the liposome model. The efficacies of pine and spruce bark extracts were ten to hundred folds higher, respectively, than those of phenolic berry extracts. The bark extracts did not significantly influence the odor or taste of the meat snacks. The findings indicate that bark extracts may be used as sustainable food ingredients. However, more research is needed to verify their safety.


Assuntos
Odorantes , Casca de Planta/química , Taninos/química , Traqueófitas/química , Antioxidantes/química , Antioxidantes/farmacologia , Aditivos Alimentares/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Estrutura Molecular , Odorantes/análise , Oxirredução/efeitos dos fármacos , Compostos Fitoquímicos , Extratos Vegetais/química , Extratos Vegetais/farmacologia
2.
Molecules ; 25(18)2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32932686

RESUMO

Developing shoots, i.e., sprouts, and older needles of Norway spruce (Picea abies (L.) Karst.) have traditionally been used for medicinal purposes due to the high content of vitamins and antioxidants. Currently, sprouts are available as, for example, superfood and supplements. However, end-product quality and nutritive value may decline in the value-chain from raw material sourcing to processing and storage. We studied (1) impacts of different drying and extraction methods on nutritional composition and antioxidative properties of sprouts and needles, (2) differences between sprouts and needles in nutritional composition and microbiological quality, and (3) production scale quality of the sprouts. Additionally, (4) sprout powder was applied in products (ice-cream and sorbet) and consumer acceptance was evaluated. According to our results, older needles have higher content of dry matter, energy, and calcium, but lower microbial quality than sprouts. Sprouts showed a higher concentration of vitamin C, magnesium, potassium, and phosphorus than older needles. Freeze-drying was the best drying method preserving the quality of both sprouts and needles, e.g., vitamin C content. The antioxidative activity of the sprout extracts were lower than that of needles. Ethanol-water extraction resulted in a higher content of active compounds in the extract than water extraction. Sensory evaluation of food products revealed that on average, 76% of consumers considered sprout-containing products very good or good, and a creamy product was preferred over a water-based sorbet.


Assuntos
Análise de Alimentos/métodos , Indústria Alimentícia/métodos , Picea/química , Brotos de Planta/química , Antioxidantes/farmacologia , Ácido Ascórbico/química , Finlândia , Manipulação de Alimentos/métodos , Magnésio/química , Noruega , Fósforo/química , Picea/microbiologia , Folhas de Planta/química , Potássio/química , Pós , Vitaminas
3.
J Dairy Sci ; 102(10): 8825-8838, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421879

RESUMO

We examined the effects of 2 grass silage-based diets differing in forage:concentrate (FC) ratio and those of a red clover silage-based diet on intake, milk production, ruminal fatty acid (FA) biohydrogenation, milk FA composition, and milk fat globule (MFG) size distribution. Ten multiparous Nordic Red cows received the following treatments: grass silage-based diets containing high (70:30, HG) or low (30:70, LG) FC ratio or a red clover silage-based diet with an FC ratio of 50:50 (RC) on a dry matter basis. Determinations of MFG were performed from fresh milk samples without addition of EDTA so the results of fat globules >1 µm in diameter are emphasized instead of the entire globule population. Lower FC ratio in grass silage-based diets increased milk production with no effect on daily fat yield, leading to 13% lower milk fat concentration. The effect of FC ratio on MFG size was moderate. It did not affect the volume-weighted diameter in grass silage-based diets, although LG lowered the volume-surface diameter of MFG in the size class >1 µm compared with HG. Compared with HG, feeding LG moderately decreased the biohydrogenation of 18:2n-6, leading to a higher level of polyunsaturated fatty acids in milk fat. Feeding RC lowered milk fat concentration and daily milk fat yield compared with grass silage-based diets. The volume-weighted diameter of MFG in the size class >1 µm was smaller in RC milk compared with grass silage-based diets. Feeding RC increased the flow of 18:3n-3 at the omasum by 2.4-fold and decreased the apparent ruminal 18:3n-3 biohydrogenation compared with grass silage-based diets despite similar intake of 18:3n-3. It also resulted in the lowest amount of saturated FA and the highest amounts of cis-9 18:1, 18:3n-3, and polyunsaturated FA in milk. In conclusion, LG decreased milk fat content and induced minor changes in MFG size distribution compared with HG, whereas RC lowered milk fat production, altered milk FA composition to nutritionally more beneficial direction, and led to smaller MFG compared with grass silage-based diets.


Assuntos
Ração Animal , Dieta/veterinária , Ácidos Graxos/análise , Glicolipídeos/química , Glicoproteínas/química , Leite/química , Silagem , Animais , Bovinos , Ácidos Graxos Insaturados/farmacologia , Feminino , Lactação , Gotículas Lipídicas , Poaceae , Silagem/análise , Trifolium
4.
FEMS Microbiol Lett ; 321(1): 10-3, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21539599

RESUMO

Propionic acid bacteria (PAB) are important as starter cultures for the dairy industry in the manufacture of Swiss-type cheeses, in which they are involved in the formation of eyes and are responsible for the typical flavour and aroma. These characteristics are mainly due to the classical propionic acid fermentation, but also the conversion of aspartate to fumarate and ammonia by the enzyme aspartase and the subsequent reduction of fumarate to succinate, which occur in dairy Propionibacterium freudenreichii ssp. shermanii and ssp. freudenreichii starter strains. Additionally, the metabolism of free amino acids may be partly responsible for secondary fermentation and the subsequent split defects in cheese matrix. Here a method for aspartase activity was established and a number of dairy propionibacteria belonging to P. freudenreichii ssp. shermanii and freudenreichii were screened for this enzyme activity. A wide range of aspartase activity could be found in PAB isolates originating from cheese. The majority, i.e. 70% of the 100 isolates tested, showed very low levels of aspartate activity.


Assuntos
Aspartato Amônia-Liase/metabolismo , Propionibacterium/enzimologia , Queijo/análise , Queijo/microbiologia , Ensaios Enzimáticos , Microbiologia de Alimentos , Reprodutibilidade dos Testes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA