Effect of NaCl and ripening time on spore germination by measuring the hydrogen production of Clostridium tyrobutyricum UC7086 in a hard cheese model

Thirty-three Lactobacillus strains were tested as adjuncts in a cheese model system. Eighteen strains originated from cheese (nine Lactobacillus spp. and nine Lb. paracasei/casei) and 15 from human intestinal mucosa (11 Lb. rhamnosus; three Lb. paracasei; one Lb. plantarum). Model cheeses weighing 120 g were made of cheese grains from full-scale production of washed curd semi-hard cheese (Herrgård). The model system was reproducible and similar to full-scale production with respect to moisture, salt content, pH and microbial flora. The model cheeses were sampled for aerobic and anaerobic plate count and viable counts of Lactobacillus and Lactococcus. The presence of adjuncts in the model cheeses was confirmed by typing isolates with Randomly Amplified Polymorphic DNA (RAPD). The sensory properties of model cheeses were described. In a first trial 23 of the 33 adjuncts were re-isolated from the corresponding model cheeses after 9 or 13 weeks. Adjuncts of Lb. paracasei were re-isolated more frequently than adjuncts of Lb. rhamnosus. Nine strains were selected, on the basis of their ability to grow and be a dominating part of the microflora of model cheese with interesting sensory properties. These strains were further studied together with two commercial cultures. The sensory influences on model cheeses of six of the adjuncts were confirmed, and flavour scores were in the range of 2.9–7.1 for model cheeses with different adjuncts while the control had a flavour score of 5.6 (0–10 scale). Survival and growth of seven out of the nine strains correlated with the results of the first trial. Growth and influence on flavour of four adjunct cultures were confirmed in experimental cheese manufactured in a 400-l open vat.

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Fermentative hydrogen production from Jerusalem artichoke by Clostridium tyrobutyricum expressing exo-inulinase gene

Scientific Reports ◽

10.1038/s41598-017-07207-7 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 7

Author(s):

Ling Jiang ◽

Qian Wu ◽

Qing Xu ◽

Liying Zhu ◽

He Huang

Keyword(s):

Hydrogen Production ◽

Jerusalem Artichoke ◽

Clostridium Tyrobutyricum ◽

Fermentative Hydrogen Production ◽

Inulinase Gene ◽

Fermentative Hydrogen

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Statistical optimization of key process variables for enhanced hydrogen production by newly isolated Clostridium tyrobutyricum JM1

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2008.05.012 ◽

2008 ◽

Vol 33 (19) ◽

pp. 5176-5183 ◽

Cited By ~ 30

Author(s):

Ji Hye Jo ◽

Dae Sung Lee ◽

Donghee Park ◽

Jong Moon Park

Keyword(s):

Hydrogen Production ◽

Statistical Optimization ◽

Clostridium Tyrobutyricum ◽

Process Variables

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Use of an Exogenous Carboxypeptidase to Accelerate Proteolysis in Reggianito Cheese

Czech Journal of Food Sciences ◽

10.17221/567/2015-cjfs ◽

2016 ◽

Vol 34 (No. 5) ◽

pp. 445-455

Author(s):

Ceruti Roberto J ◽

Pirola María B ◽

Ramos Elisabet ◽

Robert Laura ◽

Rubiolo Amelia C ◽

...

Keyword(s):

Principal Component Analysis ◽

Amino Acid ◽

Nitrogen Content ◽

Principal Component ◽

Clear Effect ◽

Ripening Time ◽

Exogenous Enzymes ◽

Amino Acid Concentrations ◽

Reggianito Cheese ◽

Hard Cheese

The effect of an exogenous commercial carboxypeptidase on the proteolysis of Reggianito cheese was evaluated. Cheeses were manufactured using 4 concentrations of enzyme: 0, 5, 10, and 20 g/100 l milk. Cheese samples were analysed at 0, 60, 90, 120, 150, 180, and 210 days of ripening. Nitrogen content values increased during ripening, but no clear effect due to the enzyme addition was observed. A profound degradation of β-casein was observed during the first 2 months of ripening in cheeses with the highest rates of enzyme addition. An increase of amino acid concentrations was clearly observed in some cheeses manufactured with exogenous enzymes compared with control cheeses at the same ripening time. However, the principal component analysis showed that experimental cheeses had a slight increase in the rate of formation and/or degradation of proteolysis products. Our results represent an important contribution to select new alternatives for enzyme addition during the manufacture of hard cheese.

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Evaluation of autochthonous cultures to improve the cheese flavor: A case study in hard cheese model

Food Science and Technology International ◽

10.1177/1082013219881512 ◽

2019 ◽

Vol 26 (2) ◽

pp. 173-184 ◽

Cited By ~ 2

Author(s):

Facundo Cuffia ◽

Carina V Bergamini ◽

Érica R Hynes ◽

Irma V Wolf ◽

María C Perotti

Keyword(s):

Volatile Compounds ◽

Selection Criterion ◽

Decanoic Acid ◽

Isoamyl Acetate ◽

Cooperative Effects ◽

Ethanoic Acid ◽

Cheese Flavor ◽

Cheese Model ◽

Hard Cheese

The characterization of autochthonous cultures based on their contribution to cheese flavor is an additional selection criterion for their use in cheese making. The objective of the present work was to assess the ability of three strains of mesophilic lactobacilli: Lactobacillus casei 72 (Lc72), L. paracasei 90 (Lp90), and L. plantarum 91 (Lp91), one strain of thermophilic lactobacillus: L. helveticus 209 (Lh209), and the thermophilic–mesophilic combinations, to grow and produce aroma compounds in a hard cheese model. Microbiological counts, pH, and the profiles of carbohydrates, organic acids, and volatile compounds were analyzed during incubation for 14 days at 37 ℃. The population of mesophilic lactobacilli reached levels around 8.0 log CFU ml−1 at three days, but then decreased until ∼7.0 log CFU ml−1 toward 14 days. Thermophilic lactobacillus population reached and maintained levels around 7.7 log CFU ml−1 during incubation. Carbohydrates were absent in the hard cheese model, and so no change in the pH values and in the levels of lactic acid was detected. Mesophilic lactobacilli, inoculated individually or in association with Lh209, metabolized the citric acid and produced ethanoic acid. The profiles of volatile compounds of mesophilic lactobacilli (characterized mainly by butan-2-one, 3-hydroxybutan-2-one, 3-methylbutan-1-ol, hexan-1-ol, 2-phenylethanol, and ethanoic acid) were different from the profile of thermophilic lactobacillus Lh209 (characterized mainly by heptan-2-one, ethyl acetate, isoamyl hexanoate, pentan-1-ol, decanoic acid, and 2- and 3-methylbutanal). Cooperative effects in the production of compounds related to cheese flavor, such as 3-hydroxybutan-2-one, ethyl butanoate, ethanol, pentan-2-ol, hexan-1-ol, benzeneacetaldehyde, 2-phenylethanol, and heptanoic acid, were largely evidenced between Lh209 and Lp91; in a lesser extent, cooperative effects were also found for Lh209+Lp90 for the following compounds: 3-hydroxybutan-2-one, isoamyl acetate, and ethanoic acid. Of the mesophilic lactobacilli strains evaluated, Lp91 and Lp90 would be interesting candidates for its use as adjunct cultures in hard cheeses to improve and diversify the flavor.

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