Rheology of spreadable goat cheese made with autochthonous lactic cultures differing in their ability to produce exopolysaccharides

The aim of this study was to compare the rheology of spreadable cheeses elaborated with autochthonous lactic starter cultures without the addition of exopolysaccharide-producing strain in the same starter with exopolysaccharide-producing strain. From a rheological standpoint, both samples were characterized as weak viscoelastic gels and pseudoplastic products. It was concluded that cheese made with exopolysaccharide-producing strain showed smaller G', G", and η* values over the range of frequencies studied and smaller critic stress values than the cheese without exopolysaccharide-producing strain. The results obtained indicate that cheeses without exopolysaccharide-producing strain need to be added with any texture enhancer product.

Chromatographic determination of fatty acids profiles in regionally-produced Portuguese goat cheese along curing

The biochemistry of cheese ripening involves mechanisms such as glycolysis, proteolysis and lipolysis. Fatty acids are released by the action of lipases from different sources, milk, rennet, bacteria, moulds included as secondary starters, and other exogenous lipases, during lipolysis [1]. The composition of the lipid fraction contributes positively to the flavour of cheese, for being precursors of more complex aroma compounds responsible for the characteristic “goaty flavour” of goat cheeses [2]. Goat milk is recognized by its easier digestibility, alkalinity, buffering capacity and certain therapeutic values in medicine and human nutrition [3]. A high total content of fatty acids is strongly linked to a rancid and tart off flavour in goat milk and may be considered undesirable in most cheese varieties [4]. In this sense, the purpose of the present study was to examine the composition and changes in fatty acids and saponification value of goat cheese during curing period (2, 7 and 12 months). Goat cheese was made in industrial unit of Cachão - Mirandela (Trás-os- Montes) with raw milk Serrana goats’ race, salt and rennet from animal origin. During the first two months, the samples were stored in a ripening chamber (9.5-11 °C and RH 75-85%). From the second month to one year, the samples were stored in a preservation chamber (10.5-12 °C and RH 75-85%). The fatty acids profile of the inner part of the cheese was analyzed by gas-chromatography coupled to flame ionization detection (GC-FID). The degree of saponification was determined both in the crust and inside the cheese by HCl titration of ethanol KOH solution of the samples. Twenty-six fatty acids (FA) were identified and quantified in the inner part of the cheese (total fat was 45-46 g/100 g during the curing period). Saturated fatty acids (SFA) did not change up to 7 months of curing, increasing only after 12 months, being palmitic (C16:0), stearic (C18:0), myristic (C14:0) and capric (C10:0) acids the most abundant FA in this class. Monounsaturated fatty acids (MUFA) decreased only after 12 months, and oleic acid (C18:1) was the predominant FA. In polyunsaturated fatty acids (PUFA) class, the most abundant were linoleic (C18:2) and linolenic (C18:3) acids, and followed the same tendency of MUFA. This is corroborated by an increase in the degree of saponification, either in the crust as in the inner part of the cheese, after 12 months of curing, probably related with the saturation of the fatty acids [3]. Extra-long curing can be done in cheeses produced with goat milk up to seven months of storage without changing the total fat and individual FA content.

Projecte de legalització d'una activitat dedicada a l'explotació ramadera i a la formatgeria artesanal

La integració en una mateixa activitat d'una explotació ramadera ecològica basada en el bestiar cabrú de llet i d'una formatgeria artesanal basada en varietats autòctones de formatge de cabra, permet ocupar un nínxol de mercat encara poc explotat actualment a Catalunya. D'igual manera, la dificultat que tenen actualment molts dels formatgers artesans del país per trobar llet de cabra en quantitats suficients i amb unes mínimes garanties higiènico-sanitàries dificulten l'avanç d'un sector amb molt bones perspectives de futur com és el de la formatgeria artesanal i justifica la necessitat de crear noves explotacions (o reconvertir-ne de ja existents) orientant-les de ple vers l'aprofitament lleter del bestiar cabrú, que és actualment molt reduït en l'àmbit Català. A més d'això, les actuals exigències en el camp del benestar animal així com en el camp de la qualitat i de la seguretat alimentaria, exigeixen a les explotacions ramaderes i a les indústries alimentàries el compliment d'una sèrie de requisits, tan de disseny dels locals i de les instal•lacions, com de control de les activitats i dels productes elaborats, que garanteixin en tot moment la seva correcte gestió i funcionament en aquestes matèries. L'objectiu d'aquest projecte, doncs, és la legalització d'una activitat, que anomenarem “Mas Peirot, S.L.”, dedicada a l'explotació ramadera ecològica de bestiar cabrú de llet i a la formatgeria artesanal de formatge de cabra. És important mencionar que tot i tractar-se d'un projecte de legalització d'una activitat,, també s'hi han contemplat aspectes i detalls relacionats amb l'execució de la mateixa, al tractar-se d'unes obres d'una certa complexitat i considerant que així es tracten amb més detall i rigorositat les actuacions projectades. En concret, en aquest projecte es planifiquen les operacions de rehabilitació de dues naus ramaderes actualment en desús, per tal que puguin destinar-se a l'explotació ramadera de bestiar cabrú i a la formatgeria artesanal, projectant-se així mateix totes les instal•lacions necessàries per tal que a les mencionades naus s'hi puguin desenvolupar les activitats citades. Com a conclusions més importants d'aquest projecte podem dir que amb un cens de 100 caps de bestiar cabrú és possible obtenir una producció mitjana de llet de 32.500 litres anuals, que es corresponen a un volum total de 3.823 quilograms de formatge a l'any (de les tipologies Formatge Garrotxa i Formatge de cabra amb oli, ambdues varietats tradicionals catalanes) obtenint un benefici de 21.389,47 Euros/any durant els primers 15 anys i un benefici de 33.386,39 Euros/any a partir del 16è any, cosa que permetrà recuperar la inversió inicial de 172.716,76 Euros que valen les naus i instal•lacions projectades, en un termini de 8 anys i permetrà, com s'ha dit, ocupar un nínxol de mercat encara poc explotat per la indústria agroalimentària a Catalunya.

Projecte de legalització d'una activitat dedicada a l'explotació ramadera i a la formatgeria artesanal

La integració en una mateixa activitat d'una explotació ramadera ecològica basada en el bestiar cabrú de llet i d'una formatgeria artesanal basada en varietats autòctones de formatge de cabra, permet ocupar un nínxol de mercat encara poc explotat actualment a Catalunya. D'igual manera, la dificultat que tenen actualment molts dels formatgers artesans del país per trobar llet de cabra en quantitats suficients i amb unes mínimes garanties higiènico-sanitàries dificulten l'avanç d'un sector amb molt bones perspectives de futur com és el de la formatgeria artesanal i justifica la necessitat de crear noves explotacions (o reconvertir-ne de ja existents) orientant-les de ple vers l'aprofitament lleter del bestiar cabrú, que és actualment molt reduït en l'àmbit Català. A més d'això, les actuals exigències en el camp del benestar animal així com en el camp de la qualitat i de la seguretat alimentaria, exigeixen a les explotacions ramaderes i a les indústries alimentàries el compliment d'una sèrie de requisits, tan de disseny dels locals i de les instal•lacions, com de control de les activitats i dels productes elaborats, que garanteixin en tot moment la seva correcte gestió i funcionament en aquestes matèries. L'objectiu d'aquest projecte, doncs, és la legalització d'una activitat, que anomenarem “Mas Peirot, S.L.”, dedicada a l'explotació ramadera ecològica de bestiar cabrú de llet i a la formatgeria artesanal de formatge de cabra. És important mencionar que tot i tractar-se d'un projecte de legalització d'una activitat,, també s'hi han contemplat aspectes i detalls relacionats amb l'execució de la mateixa, al tractar-se d'unes obres d'una certa complexitat i considerant que així es tracten amb més detall i rigorositat les actuacions projectades. En concret, en aquest projecte es planifiquen les operacions de rehabilitació de dues naus ramaderes actualment en desús, per tal que puguin destinar-se a l'explotació ramadera de bestiar cabrú i a la formatgeria artesanal, projectant-se així mateix totes les instal•lacions necessàries per tal que a les mencionades naus s'hi puguin desenvolupar les activitats citades. Com a conclusions més importants d'aquest projecte podem dir que amb un cens de 100 caps de bestiar cabrú és possible obtenir una producció mitjana de llet de 32.500 litres anuals, que es corresponen a un volum total de 3.823 quilograms de formatge a l'any (de les tipologies Formatge Garrotxa i Formatge de cabra amb oli, ambdues varietats tradicionals catalanes) obtenint un benefici de 21.389,47 Euros/any durant els primers 15 anys i un benefici de 33.386,39 Euros/any a partir del 16è any, cosa que permetrà recuperar la inversió inicial de 172.716,76 Euros que valen les naus i instal•lacions projectades, en un termini de 8 anys i permetrà, com s'ha dit, ocupar un nínxol de mercat encara poc explotat per la indústria agroalimentària a Catalunya.

Rendimento e qualidade do queijo tipo Minas Frescal de cabras alimentadas com raspa de mandioca e alfalfa

Pós-graduação em Zootecnia - FMVZ

Identificação de Staphylococcus spp. em amostras de queijos elaborados com leite de cabra.

2015

Optimization of the HS-SPME-GC/MS technique for the analysis of volatile compounds in caprine Coalho cheese using response surface methodology

Abstract Caprine Coalho cheese presents great potential for a typical protected designation of origin, considering that this traditional Brazilian cheese presents a slightly salty and acid flavor, combined with a unique texture. This study optimized the HS-SPME-GC-MS methodology for volatile analysis of Coalho cheese, which can be used as a tool to help in the identification of the distinctive aroma profile of this cheese. The conditions of equilibrium time, extraction temperature and time were optimized using the statistical tool factorial experimental design 23, and applying the desirability function. After the evaluation, it was concluded that the optimum extraction conditions comprised equilibrium and extraction time of 20 and 40 minutes, respectively; and ideal extraction temperature of 45 °C. The optimum extraction of volatile compounds in goat Coalho cheese captured 32 volatile compounds: 5 alcohols, 5 esters, 3 ketones, 6 acids, 3 aldehydes, 3 terpenes, and 7 hydrocarbons.

Probiotic caprine Coalho cheese naturally enriched in conjugated linoleic acid as a vehicle for Lactobacillus acidophilus and beneficial fatty acids

To obtain a probiotic caprine Coalho cheese naturally enriched in conjugated linoleic acid (CLA), goats' diet was supplemented with soybean oil to produce CLA-enhanced milk, and Lactobacillus acidophilus La5 was incorporated into cheeses. CLA concentration and probiotic viability were evaluated during 60 days. Four pilot-scale cheese-making trials were manufactured, in triplicates. Cheeses T1 and T2 were produced with control milk, and T3 and T4 with CLA-enhanced milk. L. acidophilus was added to cheeses T2 and T4 during processing. The CLA content (isomer C18:2 cis-9, trans-11) in T3 and T4 was 246% to 291% higher than in T1 and T2 (P < 0.01). Populations of L. acidophilus were around 7.5 log cfu g(-1) in T2 and T4 during the study, and the highest CLA content in T4 did not influence the probiotic viability (P > 0.01). The CLA-enriched probiotic caprine Coalho cheese obtained is proposed as a vehicle for beneficial microorganisms and fatty acids. (C) 2012 Elsevier Ltd. All rights reserved.

Composition, functional properties and sensory characteristics of Mozzarella cheese manufactured from different somatic cell counts in milk

In the present study, composition, functional properties and sensory characteristics of Mozzarella cheese produced from milk with somatic cell counts (SCC) at low (<200,000 cells/mL), intermediate (≈400,000 cells/mL) and high (>800,000 cells/mL) levels were investigated. Three batches of cheese were produced for each SCC category. The cheeses were vacuum packed in plastic bags and analysed after 2, 9, 16, 23 and 30 days of storage at 4ºC. SCC level did not affect the moisture, fat, total protein and ash content, mesophilic and psychrotrophic bacteria, and sensory parameters of Mozzarella cheese. However, meltability increased in cheese manufactured from high SCC milk. Results indicated that raw milk used to produce Mozzarella cheese should not contain high SCC (>800,000 cells/mL) in order to avoid changes in the functional properties of the Mozzarella cheese.

Minas-type fresh cheese developed from buffalo milk with addition of L. acidophilus

Effective incorporation of a probiotic into foods requires the culture to remain viable all along processing and storage, without adverse alterations to sensory characteristics. The objective of this work was developing Minas-type fresh cheese with probiotic properties from buffalo milk. Four batches of Minas-type fresh cheese were prepared using buffalo milk: batch T1 in which neither culture nor lactic acid added; batch T3 in which only lactic acid added; batches T2 and T4 , both added of Lactobacillus acidophilus LAC 4, but T4 was also acidified. Resulting cheeses were evaluated for probiotic culture stability, texture profile, sensory acceptance, and changes in pH. The T4 probiotic cheese presented hardness, gumminess, and chewiness significantly lower than the other treatments. However, values for springiness and cohesiveness did not differ between all cheeses, and no sensory differences (p > 0.05) were found between treatments for texture, taste, and overall acceptance. The addition of probiotic to the acidified cheese (T4) yielded best aroma. The populations of L. acidophilus were greater than 10(6) CFU g-1 after 28 days of storage all products. Minas-type fresh cheese from buffalo milk is a suitable food for the delivery of L. acidophilus, since the culture remained viable during the shelf life of the products and did not negative affect analysed parameters.

Optimal fermentation conditions for maximizing the ethanol production by Kluyveromyces fragilis from cheese whey powder

Cheese whey powder (CWP) is an attractive raw material for ethanol production since it is a dried and concentrated form of CW and contains lactose in addition to nitrogen, phosphate and other essential nutrients. In the present work, deproteinized CWP was utilized as fermentation medium for ethanol production by Kluyveromyces fragilis. The individual and combined effects of initial lactose concentration (50-150 kg m(-3)), temperature (25-35 degrees C) and inoculum concentration (1-3 kg m(-3)) were investigated through a 2(3) full-factorial central composite design, and the optimal conditions for maximizing the ethanol production were determined. According to the statistical analysis, in the studied range of values, only the initial lactose concentration had a significant effect on ethanol production, resulting in higher product formation as the initial substrate concentration was increased. Assays with initial lactose concentration varying from 150 to 250 kg m(-3) were thus performed and revealed that the use of 200 kg m(-3) initial lactose concentration, inoculum concentration of 1 kg m(-3) and temperature of 35 degrees C were the best conditions for maximizing the ethanol production from CWP solution. Under these conditions, 80.95 kg m(-3) of ethanol was obtained after 44 h of fermentation. (C) 2011 Elsevier Ltd. All rights reserved.

Chemical composition and sensory analysis of cheese whey-based beverages using kefir grains as starter culture

P>The aim of the present work was to evaluate the use of the kefir grains as a starter culture for tradicional milk kefir beverage and for cheese whey-based beverages production. Fermentation was performed by inoculating kefir grains in milk (ML), cheese whey (CW) and deproteinised cheese whey (DCW). Erlenmeyers containing kefir grains and different substrates were statically incubated for 72 h at 25 degrees C. Lactose, ethanol, lactic acid, acetic acid, acetaldehyde, ethyl acetate, isoamyl alcohol, isobutanol, 1-propanol, isopentyl alcohol and 1-hexanol were identified and quantified by high-performance liquid chromatography and GC-FID. The results showed that kefir grains were able to utilise lactose in 60 h from ML and 72 h from CW and DCW and produce similar amounts of ethanol (similar to 12 g L-1), lactic acid (similar to 6 g L-1) and acetic acid (similar to 1.5 g L-1) to those obtained during milk fermentation. Based on the chemical characteristics and acceptance in the sensory analysis, the kefir grains showed potential to be used for developing cheese whey-based beverages.

Viability of Lactobacillus acidophilus La-5 added solely or in co-culture with a yoghurt starter culture and implications on physico-chemical and related properties of Minas fresh cheese during storage

The effect of a probiotic culture of Lactobacillus acidophilus (La-5), added solely or in co-culture with a starter culture of Streptococcus thermophilus, on texture, proteolysis and related properties of Minas fresh cheese during storage at 5 degrees C was investigated. Three cheese-making trials were prepared and produced with no addition of cultures (T1 - control), supplemented with La-5 (T2), and with La-5 + S. thermophilus (T3). Viable counts of La-5 remained above 6.00 log cfu g(-1) during the whole storage for T2, reaching 7.00 log cfu g(-1) on the 14th day. For T3, the counts of La-5 remained above 6.00 log cfu g(-1) after 7 days of storage. Due to the presence of S. thermophilus, T3 presented the highest proteolytic index increase and titratable acidity values. Nevertheless, these results and S. thermophilus addition had no influence on viability of La-5 which presented satisfactory populations for a probiotic food. Moreover, the use of a yoghurt culture for the production of Minas fresh cheese T3 supplemented with La-5 resulted in a good quality product, with a small rate of post-acidification, indicating that traditional yoghurt culture could be employed in co-culture with La-5 to improve the quality of this cheese. (C) 2008 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.

Influence of Lactobacillus paracasei and inulin on instrumental texture and sensory evaluation of fresh cream cheese

The influence of the addition of a potential probiotic culture of Lactobacillus paracasei and of the prebiotic fiber inulin on the texture profile and on the sensory evaluation of probiotic and synbiotic fresh cream-cheeses was monitored. Three cheese-making trials were prepared in quintuplicate, all supplemented with a Streptococcus thermophilus starter culture (T1, T2 and T3). L. paracasei subsp. paracasei was added to T1 and T2, and inulin, to T2. The instrumental texture profile was determined after 1, 7, 14 and 21 days of storage of the cheeses. Sensory evaluation was performed after 7 days of storage. The presence of Lactobacillus paracasei in cheeses T1 and T2 and of inulin in cheeses T2 did not alter the texture profile significantly. Cheeses T1 were the least preferred in the sensory evaluation and differed signifcantly from T2 and T3, due to acidic taste, according to panelists. On the other hand, T2 was the most preferred one, though not significantly different from T3. The addition of the prebiotic ingredient inulin to fresh cream cheese processed with a potentially probiotic Lactobacillus paracasei strain resulted in a product with appropriate features and with aggregated functional properties.

Acidification rates of probiotic bacteria in Minas frescal cheese whey

The acidification rates of Lactobacillus delbrueckii subsp. bulgarieus (Lb), Lactobacillus acidophilus (La), Lactobacillus rhamnosus (Lr), and Bifidobacterium animalis subsp. lactis (Bl) in co-culture with Streptococcus thermophilus (St) were studied in Minas frescal cheese whey. Effects of the co-culture composition and the final pH values on the kinetic parameters of acidification, post-acidification and counts of health promoting micro-organisms were also studied. Fermentation time to reach pH 4.5 was longer when St-Lr co-culture was used, while St-Lb had the shortest fermentation time when compared with the other co-culture combinations. All products showed development of acidity during the storage period and lowest values had been observed employing St-Bl co-culture. The technological interest of using M. frescal cheese whey for the production of a probiotic lactic beverage is discussed in this article. (C) 2007 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.