RESUMO
The main objective of the study was to determine the effects of different fermentation parameters on kefir quality. Kefir samples were produced using kefir grains or natural kefir starter culture, and fermentation was carried out under normal or modified atmosphere (10% CO(2)) conditions. The microbiological (lactobacilli, lactococci, Lactobacillus acidophilus, Bifidobacterium spp., and yeasts), chemical (pH, lactic acid, total solids, protein, ethanol, exopolysaccharide contents), rheological, and sensory properties of kefir samples were investigated during a 21-d storage period. The use of different fermentation parameters or the choice of grain versus natural kefir starter culture did not significantly affect the content of microorganisms. Lactobacilli, lactococci, and yeast contents of kefir samples varied between 9.21 and 9.28, 9.23 and 9.29, and 4.71 and 5.53 log cfu/mL, respectively, on d 1 of storage. Contents of L. acidophilus and Bifidobacterium spp. were between 5.78 and 6.43 and between 3.19 and 6.14 log cfu/mL, respectively, during 21 d of storage. During the storage period, pH, lactic acid (%), total solids (%), protein (%), acetaldehyde, and ethanol contents of kefir samples ranged from 4.29 to 4.53, from 0.81 to 0.95%, from 7.81 to 8.21%, from 3.09 to 3.48%, from 3.8 to 23.6 mg/L, and from 76.5 to 5,147 mg/L, respectively. The exopolysaccharide contents of the samples decreased during 21 d of cold storage; the samples fermented under modified atmosphere had relatively higher exopolysaccharide contents, indicating higher potential therapeutic properties. The kefir samples exhibited non-Newtonian pseudoplastic flow behavior according to the power law model. According to the sensory results, kefir produced from natural kefir starter culture under CO(2) atmosphere had the highest overall evaluation score at d 1.
Assuntos
Produtos Fermentados do Leite/normas , Fermentação , Animais , Bifidobacterium/metabolismo , Bovinos , Produtos Fermentados do Leite/microbiologia , Qualidade dos Alimentos , Tecnologia de Alimentos/métodos , Tecnologia de Alimentos/normas , Concentração de Íons de Hidrogênio , Lactobacillus/metabolismo , Lactobacillus acidophilus/metabolismo , ReologiaRESUMO
This study was aimed to produce of hawthorn vinegar to increase the usage area and consumability of the hawthorn fruit and benefit from its functional properties, and to reveal some bioactive compounds, occurred during vinegar production, the functional properties and the volatile compounds (VC). The results showed that the gallic acid was a prominent phenolic substance in both wine and vinegar, followed by the chlorogenic acid. The prominent VACs of the hawthorn vinegar were acetic acid, phenylacetic acid, acetoin, then, respectively, pentanoic acid, benzoic acid, (E)-isoeugenol, 2-cyclohexenone, propanoic acid, chavicol, and diethyl succinate. Within this study, hawthorn vinegar was produced as a new product that had a favorable volatile aroma compound profile and phenolic compounds with high bioactivity. Hawthorn vinegar that shown as an alternative way for the use of hawthorn fruit, its of whose functional and aromatic aspect was first revealed in detail. PRACTICAL APPLICATIONS: Hawthorn is a seasonal fruit, which has potential to be economically important. It has rich bioactive compounds known to have a positive effect on health. However, organoleptic properties (astringent, grainy texture, etc.) of fresh hawthorn fruit are not be mostly liked among most of the consumers. This situation prevents benefiting from the positive effect of hawthorn fruit. For this reason, in this study, it was aimed to produce the hawthorn vinegar, which economically more valuable and also, more functional than fresh hawthorn fruit. According to the results of the present study, organoleptic, functional, and economic values of the hawthorn fruit were improved with the hawthorn vinegar produced in result of the fermentation process. So, it has been considered that this study is beneficial for consumers, scientist or food industry professionals as it guides to transform a low-economic food product to highly economic and functional food product.
Assuntos
Crataegus , Vinho , Ácido Acético , Frutas/química , Odorantes , Vinho/análiseRESUMO
Kefir is a unique cultured dairy product due to combined lactic acid and alcoholic fermentation of lactose in milk. Kefir is produced by microbial activity of "kefir grains" which have a relatively stable and specific balance of lactic acid bacteria and yeast. Due to the claimed health benefits of kefir which include reduction of lactose intolerance symptoms, stimulation of the immune system, lowering cholesterol, and antimutagenic and anticarcinogenic properties, kefir has become an important functional dairy food and consequently, research on kefir has increased in the past decade. In the following review, recent studies on the functional properties of kefir are reviewed.
Assuntos
Produtos Fermentados do Leite/microbiologia , Produtos Fermentados do Leite/fisiologia , Microbiologia de Alimentos , Lactobacillaceae/crescimento & desenvolvimento , Adjuvantes Imunológicos , Antibiose , Anticarcinógenos , Anticolesterolemiantes , Alimentos Orgânicos , HumanosRESUMO
In this study, it was aimed to determine the bioactive compounds and volatile aroma compounds of the sour cherry vinegar, and to investigate the usability of concentrated juice instead of the fresh fruit juice in vinegar production. And, two sour cherry vinegars were produced using juices prepareted fresh fruit (FSCJ) and concentrate juice (CSCJ), analyzed for functional and organoleptic aspects. The finding shown that both vinegars produced have rich functional compounds (gallic and chlorogenic acids) and volatile aroma compounds, and sour cherry is ideal for vinegar production. However, the vinegar produced using the CSCJ was more prominent, according to aromatic aspect. These aroma compounds were 3-methyl-1-butanol and eugenol, phenethyl alcohol, 2-phenethyl acetate, acetic, isobutyric, isovaleric, hexanoic and octanoic acids. Within this study, a new way for sour cherry usage, independently of the season were proposed. And, aromatic and functional aspects of sour cherry vinegar were revealed for the first time.
Assuntos
Ácido Acético/análise , Antioxidantes/química , Sucos de Frutas e Vegetais/análise , Prunus avium/química , Compostos Orgânicos Voláteis/química , Frutas/química , Frutas/metabolismo , Concentração de Íons de Hidrogênio , Fenóis/química , Prunus avium/metabolismo , Refratometria , EspectrofotometriaRESUMO
Kefir is a probiotic and fermented dairy product authentically produced from kefir grains. Kefir grain, as a natural starter culture, contains numerous lactic acid bacteria, acetic acid bacteria and yeasts within a polysaccharide structure. True kefir is a miraculous food in terms of its favorable contributions to human health. However, kefir starter cultures used in industrial kefir productions contain very few lactic acid bacteria and yeasts. These starter cultures do not contain characteristic kefir bacteria, such as Lactobacillus kefiranofaciens, Lactobacillus kefiri, and Lactobacillus parakefiri. The objective of this study was to compare the intestinal microorganisms of BALB/c mice fed kefir produced from natural kefir grains and kefir produced from starter culture. The mice in kefir groups were fed an oral dose of 0.3â¯mL kefir/day for 15â¯days, and the control group did not receive kefir. The feces were collected in metabolic cages, and the lactic acid bacteria, yeasts-fungi, and Lactobacillus acidophilus and Bifidobacterium species were determined. Additionally, PCR analysis based on yeast-fungus 23S rRNA was carried out, and serial analysis was performed with an ABI 3100 Genetic Analyzer. Serum total antioxidant status (TAS), serum total oxidant status (TOS) levels, malondialdehyde (MDA) levels and myeloperoxidase (MPO) levels were determined. The mean lactic acid bacteria (LAB) contents of the feces samples obtained from the mice fed kefir samples produced from kefir grains and starter culture were 9.08 log cfu/g and 7.32 log cfu/g on the 15th day, respectively. Mold was found in both the starter kefir group and in the control group (range, 1.91-2.02 log cfu/g). The mold was identified as Trichoderma koningii, a potential human pathogen and carcinogen. It was very impressive that mold was not observed in the feces samples of the mice fed the kefir produced from kefir grains. The highest TAS value was determined in the serum samples of mice fed kefir produced using kefir grains. MPO values in the small intestines of mice fed kefir produced using starter culture were higher than those in the CK group that was associated with possible inflammation. This study might lead to new studies focused on the antifungal effects of kefir and on the importance of using kefir grains in the production of kefir.
Assuntos
Antioxidantes/metabolismo , Produtos Fermentados do Leite/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Kefir , Probióticos/farmacologia , Animais , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Bactérias/isolamento & purificação , Fezes/microbiologia , Fungos/efeitos dos fármacos , Fungos/isolamento & purificação , Lactobacillales/efeitos dos fármacos , Lactobacillales/isolamento & purificação , Lactobacillus/isolamento & purificação , Masculino , Malondialdeído/sangue , Camundongos , Camundongos Endogâmicos BALB C , Peroxidase/sangue , RNA Ribossômico 23S/genética , Trichoderma/efeitos dos fármacos , Trichoderma/isolamento & purificação , Leveduras/efeitos dos fármacosRESUMO
Red delicious apples were used to produce natural apple cider with and without inclusion of maceration. Traditional surface and industrial submersion methods were then applied to make vinegar from apple ciders. Apple cider vinegar samples produced with inclusion of maceration in the surface method had the highest total phenolic content, chlorogenic acid, ORAC, and TEAC levels. Cholesterol and apple vinegar samples were administered using oral gavage to all groups of rats except the control group. Apple cider vinegars, regardless of the production method, decreased triglyceride and VLDL levels in all groups when compared to animals on high-cholesterol diets without vinegar supplementation. Apple cider vinegars increased total cholesterol and HDL and LDL cholesterol levels and decreased liver function tests when compared to animals on a high-cholesterol diet without vinegar supplementation. A high-cholesterol diet resulted in hepatic steatosis. VSBM and VSB groups significantly decreased steatosis.