Development of Kefir beverages: Standardization of process parameters

Abstract The purpose of this study was to investigate the microbiological (number of viable lactic acid bacteria and bifidobacteria), physicochemical (dry matter, protein and fat contents, titratable acidity, and pH), and sensory characteristics (appearance of coagulum, taste and aroma, structure at cutting, color, and consistency at shattering) of probiotic Bulgarian yoghurts obtained by ultrafiltration of goat’s milk. These yoghurts were obtained using volume reduction ratios of 2 and 3 with the probiotic starters MZ2f, MZ2f + Bifidobacterium bifidum BB – 87, and MZ2f + Lactobacillus acidophilus LAB – 8. The increase in the level of the concentration by ultrafiltration led to an increase in the dry matter, protein and fat contents of the yoghurts, in the number of lactic acid bacteria and titratable acidity, and to a decrease in the pH. The twofold concentration by ultrafiltration resulted in a higher number of lactic acid bacteria in comparison with yoghurts made without ultrafiltration, and with better sensory characteristics compared to yoghurts without and with threefold ultrafiltration. The higher number of viable cells and better sensory characteristics were obtained for yoghurts with MZ2f + Bifidobacterium bifidum BB – 87 and MZ2f + Lactobacillus acidophilus LAB – 8 in comparison with MZ2f alone.

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Effect of the application of probiotic strains of Enterococcus faecium on the physicochemical and sensory characteristics of coalho cheese

Semina Ciências Agrárias ◽

10.5433/1679-0359.2021v42n1p167 ◽

2021 ◽

Vol 42 (1) ◽

pp. 167-178

Author(s):

Tatiane de Oliveira Xavier Machado ◽

◽

Roberta Verônica dos Santos Carvalho Mesquita ◽

Vanicleia Oliveira da Sillva ◽

Micaele Bagagi Araújo ◽

...

Keyword(s):

Lactic Acid ◽

Organic Acid ◽

Enterococcus Faecium ◽

Microbiological Quality ◽

Titratable Acidity ◽

Sensory Characteristics ◽

Cow Milk ◽

Probiotic Properties ◽

Organic Acid Profile ◽

Probiotic Strains

Coalho cheese is a typical Northeastern Brazilian food whose production and consumption has expanded considerably to other regions of the country. Despite its cultural and socioeconomic relevance, coalho cheese still has a negative reputation due to problems in its physicochemical and microbiological quality standards, especially when it is produced artisanally. For this reason, many researchers have been looking for alternatives to improve the quality and the notoriety of this product, such as the application of probiotic strains to inhibit pathogens. However, in addition to the research related to the desired probiotic properties and the safety of strains for food application, it is important to know the possible changes in the food matrix caused by this intervention. In this context, the aim of this study was to evaluate the effect of the incorporation of probiotic strains of Enterococcus faecium on the physicochemical and sensory characteristics of coalho cheese. The cheeses were made with pasteurized cow milk and probiotic strains of E. faecium were added during production. Cheeses were also made without adding the strains, and considered as control cheeses. The final products were evaluated for moisture, pH, titratable acidity, total carbohydrates, proteins, lipids, ash, color, organic acid profile, and sensory attributes. In addition, viable lactic acid bacteria were also assessed. Coalho cheeses containing E. faecium showed higher titratable acidity and lower pH. In addition, there was a reduction in the carbohydrate content, which was attributed to lactose degradation. The organic acid profile also varied, as highlighted by the increase in the concentration of lactic acid by a factor of 3.5, and by the absence of citric acid as a possible result of the metabolism of E. faecium in the production of aromatic compounds. There was no variation in the color or sensory acceptance of the cheeses. Therefore, the application of probiotic strains of E. faecium in coalho cheese production changes some physicochemical characteristics while maintaining essential properties, such as the color and sensory acceptability of the final product.

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Effects of Lactic Acid Fermentation on the Retention of Β-Carotene Content in Orange Fleshed Sweet Potatoes

International Journal of Food Studies ◽

10.7455/ijfs/3.1.2014.a2 ◽

2014 ◽

Vol 3 (1) ◽

Cited By ~ 10

Author(s):

Benard O. Oloo ◽

A. A. Shitandi ◽

S. Mahungu ◽

J. B. Malinga ◽

Rose B. Ogata

Keyword(s):

Lactic Acid ◽

Sweet Potato ◽

Titratable Acidity ◽

Lactic Acid Fermentation ◽

Process Conditions ◽

Sweet Potatoes ◽

Acid Fermentation ◽

Carotene Content ◽

Fermentation Time ◽

Β Carotene

This study aimed to establish the effects of lactic fermentation on the levels of β-carotene in selected orange fleshed sweet potato (OFSP) varieties from Kenya. Furthermore,it sought to demonstrate fermentation as a potential process for making new products from sweet potato with enhanced nutraceutical attributes. The varieties (Zapallo, Nyathiodiewo and SPK004/06) were fermented with Lactobacillus plantarum MTCC 1407 at 25 ± 2°C for 48 h and kept for 28 days to make lacto-pickles. During fermentation both analytical [pH, titratable acidity (TA), lactic acid (LA), starch, total sugar, reducing sugar (g/kg roots), texture (N/m2), β-carotene (mg/kg roots)] and sensory (texture, taste, flavour and after taste) attributes of sweet potato lacto-juice were evaluated. Process conditions were optimized by varying brine levels, with fermentation time. A UV-visible spectrophotometer was used to identify and quantify β-carotene. Any significant variations (p < 0.05) in analytical attributes between the fermented and unfermented samples (pH, LA, TA and β-carotene concentration) of lacto-pickles, prepared from the potato roots, were assessed. The study reported a final composition of 156.49mg/kg, 0.53mg/kg, 0.3N/m2, 1.3g/kg, 5.86g/kg, 0.5g/kg and 5.86g/kg for β-carotene, Ascorbic acid, texture; Starch, total sugars, LA and TA respectively, and a pH of 3.27. The fermented products were subjected to flavour profiling by a panel. The product sensory scores were 1.5 to 2.5 on a 5 point hedonic scale, ranging from dislike slightly to like much. The products with brine levels at 4 and 6% were most preferred. The retention of β-carotene was 93.97%. This demonstrated lactic acid fermentation as a better method for processing OFSP as the main nutritional attributes are retained. The final product was resistant to spoilage microorganisms after 28 days of fermentation. Further preservation could be obtained by addition of sodium metabisulphite. In conclusion, Lactic acid fermentation using L. plantarum is a novel method of producing Lacto pickles from Zapallo OFSP, with 93.97% β-carotene retention and adequate shelf life.

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Effect of Lactobacillus rhamnosus on Physicochemical Properties of Fermented Plant-Based Raw Materials

Foods ◽

10.3390/foods9091182 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1182 ◽

Cited By ~ 2

Author(s):

Carmen Masiá ◽

Poul Erik Jensen ◽

Patrizia Buldo

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Physicochemical Properties ◽

Food Industry ◽

Raw Materials ◽

Lactobacillus Rhamnosus ◽

Titratable Acidity ◽

Fermentation Time ◽

Trained Panel ◽

Volatile Organic

Texture and flavor are currently the main challenges in the development of plant-based dairy alternatives. To overcome them, the potential of microorganisms for fermentation of plant-based raw materials is generating great interest in the food industry. This study examines the effect of Lactobacillus rhamnosus, LGG® (LGG® is a trademark of Chr. Hansen A/S) on the physicochemical properties of fermented soy, oat, and coconut. LGG® was combined with different lactic acid bacteria (LAB) strains and Bifidobacterium, BB-12® (BB-12® is a trademark of Chr. Hansen A/S). Acidification, titratable acidity, and growth of LGG® and BB-12® were evaluated. Oscillation and flow tests were performed to analyze the rheological properties of fermented samples. Acids, carbohydrates, and volatile organic compounds in fermented samples were identified, and a sensory evaluation with a trained panel was conducted. LGG® reduced fermentation time in all three bases. LGG® and BB-12® grew in all fermented raw materials above 107 CFU/g. LGG® had no significant effect on rheological behavior of the samples. Acetoin levels increased and acetaldehyde content decreased in the presence of LGG® in all three bases. Diacetyl levels increased in fermented oat and coconut samples when LGG® was combined with YOFLEX® YF-L01 and NU-TRISH® BY-01 (YOFLEX® and NU-TRISH® are trademarks of Chr. Hansen A/S). In all fermented oat samples, LGG® significantly enhanced fermented flavor notes, such as sourness, lemon, and fruity taste, which in turn led to reduced perception of the attributes related to the base. In fermented coconut samples, gel firmness perception was significantly improved in the presence of LGG®. These findings suggest supplementation of LAB cultures with LGG® to improve fermentation time and sensory perception of fermented plant-based products.

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Evaluation of Yoghurts with Thyme, Thyme Essential Oil and Salt

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun201866020365 ◽

2018 ◽

Vol 66 (2) ◽

pp. 365-369

Author(s):

Viera Ducková ◽

Miroslav Kročko ◽

Vladimíra Kňazovická ◽

Margita Čanigová

Keyword(s):

Lactic Acid ◽

Essential Oil ◽

Bitter Taste ◽

Control Sample ◽

Titratable Acidity ◽

Coliform Bacteria ◽

Thymus Vulgaris ◽

Fermentation Time ◽

Ph Values ◽

Thyme Essential Oil

The aim of this work was production and evaluation of yoghurts with different addition of thyme (Thymus vulgaris), thyme essential oil (EO) and salt. It was produced: control yoghurt, yoghurt with 0.45 % of salt and 0.25 % of thyme, yoghurt with 0.90 % of salt and 0.50 % of thyme, yoghurt with 0.45 % of salt and 0.004 % of thyme EO, yoghurt with 0.90 % of salt and 0.008 % of thyme EO. The time of yoghurt fermentation was extended from the previous 3.5 hours (control sample) to 5 hours for samples with thyme or even up to 7 hours for samples with thyme EO. The fermentation time also depended on the concentration of the used substances. The average titratable acidity of yoghurts fluctuated from 46.52 °SH to 49.51 °SH at day after the production and from 51.57 °SH to 55.75 °SH after 7 days of storage. Average pH values of yoghurts fluctuated from pH 4.77 to pH 4.81 at day after production and from pH 4.48 to pH 4.63 after storage. In all samples of yoghurts were not detected coliform bacteria (< 10 CFU.g-1). The yeasts were appeared rarely (101 CFU.g-1), and their numbers were increased during cold storage (102 up to 103 CFU.g-1). Moulds appeared rarely (101 CFU.g-1). The number of lactic acid bacteria reached required minimum value of 107 CFU.g-1. Samples of yoghurts reached characteristic yoghurt and thyme aroma. The intensity of sour, salty and thyme taste, determined by sensory evaluation was in experimental samples of yoghurts at different level. A higher concentration of thyme and thyme EO gave to yoghurts a bitter taste. The dense consistency of the yoghurts was decreased with the increased addition of thyme and thyme EO. According to results, we recommend the recipe of yogurt with 0.45 % of salt and 0.25 % of thyme or 0.004 % of thyme EO.

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Microbial load, physico-chemical properties, and organic acid profile of a naturally fermented carabeef, Pindang damulag, as affected by fermentation time

Food Research ◽

10.26656/fr.2017.4(2).275 ◽

2018 ◽

Vol 4 (2) ◽

pp. 312-319

Author(s):

M.A.S. Esteban ◽

L.E. Mopera ◽

M.C.R. Oliveros ◽

E.I. Dizon

Keyword(s):

Lactic Acid ◽

Organic Acid ◽

Chemical Properties ◽

Titratable Acidity ◽

Soluble Solids ◽

Fermentation Time ◽

Physico Chemical ◽

Production And Consumption ◽

Organic Acid Profile ◽

Acid Producing Bacteria

Pindang damulag or fermented carabeef is a native traditional food from Pampanga, Philippines. It is produced by mixing thin slices of carabeef with curing ingredients, then storing the mixture in an anaerobic condition, and left through the action of naturally growing lactic acid bacteria (LAB) via fermentation for 1 week at room temperature. However, the practice of production and consumption of pindang damulag is slowly dying and there are only very limited scientific studies on pindang damulag. Therefore, the study aimed to identify the LAB present and determine its contribution to the microbial diversity, physico-chemical properties, and organic acid profile of pindang damulag during natural fermentation. During fermentation, standard serial dilution and plating show that all targeted groups of microorganisms (fungi, common bacteria, coliforms, acid producing bacteria and LAB) grew significantly until the 3rd day. After day 3, only acid producing bacteria and LAB grew significantly. There was also a significant decrease in total soluble solids (TSS) from day 0 to day 3 (30.31 – 28.17°Brix), while titratable acidity (TA) and pH were found to be statistically constant (3.5% at pH 5.97 – 3.6% at pH 5.9). Moreover, significant decrease in TSS (24.89, 22.76, and 20.53°Brix) and pH (5.60, 4.93, and 4.53) were observed, while TA increased significantly (4.5, 5.6, 6.6%) during days 5, 7, and 9. After the culture dependent phenotypic and genotypic tests using 27F and 1492R primer pairs, LAB isolates were found to be homologous to Enterococcus faecium and Weisella paramesenteroides. The former exhibited proteolytic activity on pindang damulag which broke down the protein chains with approximate MW of 20.1KDalton as observed in the acrylamide gel from SDS-PAGE. The other LAB was known to be a heterofermentative LAB, which reflected on the predominance of other organic acids such as citric acid (448.70 mg/100 g), acetic acid (1724 mg/100 g) other than the lactic acid (4440 mg/100 g) alone, using RP-HPLC. Therefore, LAB was found to have a major role in the food safety, food quality and overall profile of pindang damulag.

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Effects of Lactic Acid Fermentation on the Retention of Β-Carotene Content in Orange Fleshed Sweet Potatoes

International Journal of Food Studies ◽

10.7455/ijfs.v3i1.187 ◽

2014 ◽

Vol 3 (1) ◽

Author(s):

Benard O. Oloo ◽

A. A. Shitandi ◽

S. Mahungu ◽

J. B. Malinga ◽

Rose B. Ogata

Keyword(s):

Lactic Acid ◽

Sweet Potato ◽

Titratable Acidity ◽

Lactic Acid Fermentation ◽

Process Conditions ◽

Sweet Potatoes ◽

Acid Fermentation ◽

Carotene Content ◽

Fermentation Time ◽

Β Carotene

This study aimed to establish the effects of lactic fermentation on the levels of β-carotene in selected orange fleshed sweet potato (OFSP) varieties from Kenya. Furthermore,it sought to demonstrate fermentation as a potential process for making new products from sweet potato with enhanced nutraceutical attributes. The varieties (Zapallo, Nyathiodiewo and SPK004/06) were fermented with Lactobacillus plantarum MTCC 1407 at 25 ± 2°C for 48 h and kept for 28 days to make lacto-pickles. During fermentation both analytical [pH, titratable acidity (TA), lactic acid (LA), starch, total sugar, reducing sugar (g/kg roots), texture (N/m2), β-carotene (mg/kg roots)] and sensory (texture, taste, flavour and after taste) attributes of sweet potato lacto-juice were evaluated. Process conditions were optimized by varying brine levels, with fermentation time. A UV-visible spectrophotometer was used to identify and quantify β-carotene. Any significant variations (p < 0.05) in analytical attributes between the fermented and unfermented samples (pH, LA, TA and β-carotene concentration) of lacto-pickles, prepared from the potato roots, were assessed. The study reported a final composition of 156.49mg/kg, 0.53mg/kg, 0.3N/m2, 1.3g/kg, 5.86g/kg, 0.5g/kg and 5.86g/kg for β-carotene, Ascorbic acid, texture; Starch, total sugars, LA and TA respectively, and a pH of 3.27. The fermented products were subjected to flavour profiling by a panel. The product sensory scores were 1.5 to 2.5 on a 5 point hedonic scale, ranging from dislike slightly to like much. The products with brine levels at 4 and 6% were most preferred. The retention of β-carotene was 93.97%. This demonstrated lactic acid fermentation as a better method for processing OFSP as the main nutritional attributes are retained. The final product was resistant to spoilage microorganisms after 28 days of fermentation. Further preservation could be obtained by addition of sodium metabisulphite. In conclusion, Lactic acid fermentation using L. plantarum is a novel method of producing Lacto pickles from Zapallo OFSP, with 93.97% β-carotene retention and adequate shelf life.

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Frozen yogurt from sheep milk

Revista CERES ◽

10.1590/0034-737x201663050003 ◽

2016 ◽

Vol 63 (5) ◽

pp. 605-613 ◽

Cited By ~ 3

Author(s):

Elisangela de Abreu ◽

Jamile Zeni ◽

Clarice Steffens ◽

Juliana Steffens

Keyword(s):

Lactic Acid ◽

Experimental Design ◽

Lactic Acid Bacteria ◽

Sensory Analysis ◽

Central Point ◽

Sensory Characteristics ◽

Instrumental Analysis ◽

Fecal Coliforms ◽

Sheep Milk ◽

Frozen Yogurt

ABSTRACT The aim of this work was to develop frozen yogurt formulations from powdered yogurt of sheep milk, through an experimental design of 2², with a triplicate at the central point. The variables studied were emulsifier/stabilizer (0.50%, 0.75%, and 1.00%) and powder for cream (2.75%, 3.00% and 3.25%). The parameters evaluated were sensory characteristics, texture, and microbiological counts. The results showed that the formulations had counts of S. aureus and fecal coliforms at 45 °C, lactic acid bacteria and Salmonella sp within the limits established by legislation. Instrumental analysis of texture-related parameters (firmness, cohesiveness, adhesiveness, and consistency) of the formulations with different concentrations of emulsifier/stabilizer and cream powder showed no significant differences (p > 0.05). In sensory analysis, Formulations 3 and 4 with lower concentrations of emulsifier/stabilizer scored the highest values, thus indicating good acceptability.

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The sensory characteristics of berry-flavoured kefir

Czech Journal of Food Sciences ◽

10.17221/3290-cjfs ◽

2011 ◽

Vol 24 (No. 1) ◽

pp. 26-32 ◽

Cited By ~ 6

Author(s):

L. YILMAZ ◽

T. ÖZCAN YILSAY ◽

A. AKPINAR BAYIZIT

Keyword(s):

Sensory Analysis ◽

Storage Time ◽

Titratable Acidity ◽

Sensory Characteristics ◽

Refrigerated Storage ◽

Alcohol Content ◽

Overall Acceptability ◽

Kefir Grains ◽

Mouth Feel

Certain physicochemical and sensory characteristics of the flavoured kefir drink were studied during refrigerated storage. Kefir drink batches were prepared using 2% addition of kefir grains, incubation for 18 h and subsequent filtration. The batches were then flavoured with blackberry, raspberry and strawberry aromas in the concentrations of 0.05, 0.10 and 0.15%, respectively. The samples were taken for analysis on 1st, 4th, 7th, and 10th days of storage at 4 ± 1°C. The sensory analysis of the flavoured kefir samples revealed the best acceptability level on the 4th day of storage. Nevertheless, the samples were acceptable all throughout the storage. The percentage of the aroma addition significantly influenced the odour, flavour, texture, and mouth-feel, and the overall acceptability ratings. The higher percentage of the added aroma the more sensed, however, the lowest aroma addition was preferable. The pHs of the flavoured kefir drinks decreased throughout the storage time whereas, the titratable acidity, alcohol content and CO2 values increased.

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Evaluation of Microbial and Nutritional Quality of Fermented Dried Roasted Thick Porridge (Mkarango)

Asian Food Science Journal ◽

10.9734/afsj/2019/v8i329993 ◽

2019 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

E. C. Cheruiyot ◽

S. K. Mbugua ◽

M. W. Okoth ◽

O. G. Abong ◽

D. M. Kaindi

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Nutritional Quality ◽

Titratable Acidity ◽

Lactobacillus Brevis ◽

Sensory Characteristics ◽

Maize Flour ◽

Fermentation Products ◽

Ph Values

Most of the products of maize flour fermentation in Kenya undergo wild fermentation in a natural process. One of these is locally roasted maize flour commonly known by its local name Mkarango which is popular in the Western region of Kenya where it is used in different ways. Mkarango is mostly made through wild fermentation which is known to pose health risks as it is unhygienic and time-consuming, with the quality of the resultant product being inconsistent. The aim of this study was to evaluate the population of lactic acid bacteria, and sensory characteristics of dried roasted thick porridge (mkarango). Six different mkarango products made with addition of Lactobacillus plantarum and Lactobacillus brevis in different ratios were studied for microbial quality, mineral element content and sensory characteristics. Titratable acidity and pH properties of the products were also determined. These were done following recommended standards. After 24 hours of fermentation, products with Yeast+ L. plantarum+ L. brevis (1:2) and Milk+ L. plantarum+ L. brevis (1:2) had the highest pH values (5.12) while products with Milk+ L. plantarum+ L. brevis (2:1) had the lowest pH values (4.8). Yeast, molds, and Lactic Acid Bacteria had the highest in all the samples tested while Enterobacteriaceae the least. The overall acceptability of the product of the product prepared from Milk + L. plantarum + L. brevis (2:1) had the final score of 4.7 on the 5-point hedonic scale. The results of the trace elements zinc and iron ranged from 2.7 mg/100 g to 3.9 mg/100 g and 2.7 mg/100 g to 16.9 mg/100 g on the product respectively. Fermentation creates an environment that is conducive for the population of lactic acid bacteria. This results in increased volume of lactic acid that is responsible for improved nutritional quality of Mkarango.

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