scholarly journals The influence of incubation temperature and starter culture type on physical properties of ayran

Author(s):  
Firuze Emilia Ergin

In this study, the effects of the incubation temperature and type of starter culture on the physical properties, including graininess and visual roughness, of ayran were determined. Ayran samples were produced from milk inoculated with two different starter cultures (Yo-Mix 410, Yo-Mix 883) and incubated at temperatures of 37 or 45°C, and then stored at 4°C for 15 days. As incubation temperature decreased the number and perimeter of grains and syneresis decreased and the amount of exopolysaccharide (EPS) increased in ayran samples. The high amount of EPS resulted in low syneresis value, the number and perimeter of grains and visual roughness in ayran samples. The apparent viscosity and consistency coefficient values of ayran samples produced from milk incubated at 37°C were higher than those from milk incubated at 45°C. The Power law model was found more satisfactory to describe flow behaviour of all ayran samples. The rheological properties of ayran samples changed with measurement temperature. As the measurement temperature increased from 5°C to 15°C, the apparent viscosity and consistency coefficient values of ayran samples were significantly decreased. The activation energy values for apparent viscosity of ayran samples varied depending on the incubation temperature, type of starter culture and storage period.

2006 ◽  
Vol 12 (6) ◽  
pp. 467-476 ◽  
Author(s):  
Ö. Gün ◽  
N. D. Işsikli

The effects of fat and non fat dry matter (NFDM) concentration and storage time on the physical properties and acidity of yoghurts made using commercial probiotic cultures (ABY and ABT-1) were investigated by using response surface methodology. All yoghurts made with ABY and ABT-1 cultures exhibited shear thinning behaviour. The power low model was used to describe the shear thinning behaviour of yoghurt samples. The flow behaviour index ( n) and the consistency coefficient ( m) were determined. NFDM levels in milk strongly affected syneresis, apparent viscosity at a constant speed of 100rpm, flow behaviour index and the consistency coefficient. Titratable acidity and pH were mainly affected by the storage time. Under all conditions examined, yoghurt made with ABT-1 culture had higher apparent viscosity, consistency coefficient and pH value than those of the yoghurt made using ABY culture.


1988 ◽  
Vol 51 (5) ◽  
pp. 386-390 ◽  
Author(s):  
Y. A. EL-SAMRAGY ◽  
E. O. FAYED ◽  
A. A. ALY ◽  
A. E. A. HAGRASS

The traditional yogurt starter, i.e. Staphylococcus thermophilus and Lactobacillus bulgaricus, has always been used to bring about the lactic acid fermentation during manufacture of concentrated yogurt known in Egypt as “Labneh”. Different combinations of some strains of Enterococcus faecalis, isolated from Laban Rayeb (a type of fermented milk), in combination with a certain strain of Lactobacillus bulgaricus were used to produce a Labneh-like product. Chemical, microbiological and organoleptic properties of the Labneh-like product were assessed and compared to the characteristics of Labneh processed traditionally by two different dairy plants in Egypt. All treatments showed similar changes during storage at 5 ± 1°C for 28 d. Total solids, fat, titratable acidity and pH values coincided with those of Labneh. Some components increased until the seventh day, i.e. acetaldehyde and diacetyl, while other features, such as the ratio of soluble nitrogen/total nitrogen and tyrosine, increased until the fourteenth day of storage. Thereafter, no marked variations occurred. However, a decrease in tryptophan content of all products occurred during the storage period. Total viable count and count of lactic acid bacteria of Labneh-like product as well as Labneh increased until the end of the second week of storage and then decreased. Coliforms, yeasts and molds and psychrotrophic bacteria were detected in some fresh and stored samples. The starter culture which consisted of 1.5% Enterococcus faecalis 19 and 1.5% Enterococcus faecalis 22 was used successfully to manufacture a Labneh-like product with high acceptability when fresh or refrigerated at 5 ± 1°C.


2013 ◽  
Vol 115 (8) ◽  
pp. 1169-1186 ◽  
Author(s):  
Muhammad Saeed ◽  
Faqir Muhammad Anjum ◽  
Moazzam Rafiq Khan ◽  
Muhammad Issa Khan ◽  
Muhammad Nadeem

PurposeWhey products have conventionally been professed as a means of reducing ingredient costs. The authentic benefits of adding whey products are the enhanced worth resulting from flavor, texture and nutritional improvements as well as nutraceutical or health‐enhancing payback. Therefore, the present study aims to isolate and characterize suitable starter cultures for the production of wheyghurt drink.Design/methodology/approachKeeping in view all the benefits of yoghurt technology this study was planned to isolate the starter cultures and optimize the conditions for the production of wheyghurt drink. The starter cultures (Lactobacillus delbruceckii ssp. Bulgaricus and Streptococcus thermophilus) were isolated from the yoghurt and further characterized on the basis of their morphological and biochemical characteristics. The wheyghurt drink prepared from starter cultures with varying starter culture concentrations (1, 1.5, 2 and 2.5 percent) was analyzed for the physicochemical and sensory characteristics to explore the potential of wheyghurt drink.FindingsDuring storage, color, flavor, taste and overall acceptability were affected significantly. But the interaction between treatments and storage was found non‐significant to all the sensory parameters. At zero day maximum score (7.40) for overall acceptability was recorded for T3 and minimum score (5.60) was awarded to T4. After five, ten and 15 days of storage, judges observed a slight decline in overall acceptability in all wheyghurt drink samples. Hence it was concluded that wheyghurt drink sample T3 obtained maximum scores regarding the organoleptic evaluation and remained the best.Practical implicationsThe key to growth is a continuous evaluation and modification of the product to match consumer expectations. Currently there are many apparent benefits that result from incorporating selected whey products into yogurt formulas. The starter cultures for the production of fermented whey products are not presently produced in Pakistan and are imported for industrial use. The use of LAB as starter culture may help to improve the quality and shelf life of the whey products.Originality/valueThe research is useful for food manufacturers in order to develop functional food products for consumers. Understanding consumer needs and preferences is critical to successful product development and enhancing marketing values of a product. Nutritionally improved foods, such as wheyghurt over the conventional counterpart, will be highly successful in the marketplace. Consumers will prefer such kinds of foods because they are more conscious about their health and such foods provide them with what they desire, i.e. health benefits with good nutrition.


2016 ◽  
Vol 6 (1) ◽  
pp. 34-38
Author(s):  
Happy Nursyam ◽  
Widjanarko S B ◽  
Sukoso Sukoso

Lactic acid bacteria (LAB) consist of four genera, namely Lactobacillus, Leuco-nostoc, Pediococcus, and Streptococcus. Pediococcus and Lactobacillus are used as starter cultures in the processing of fermented food products such as sour milk, shrimp paste and fermented sausage. . The use of starter culture is intended to speed up the fermentation process as well as inhibiting the growth of other pathogenic bacteria. Common LAB are gram-positive, do not have spores, cocci or bacilli, and produce lactic acid from the fermenta-tion of carbohydrates. Antimicrobial components produced by LAB can inhibit the growth of pathogenic bacteria in fermented products, for example Pediocin produced by P. acidilactici and Lactasin by L. casei. Fermented meat products may possibly be contaminated by Listeria monocytogenes if the implementation is not hygienic. In fermented sausage processing, commonly used preservatives are: NaCl, NaNO2, NaNO3, liquid smoke, pH, and lactic acid. The purpose of this study was to determine the survival of Pediococcus acidilactici, Lactobacillus casei, and Listeria monocytogenes in some kind of curing with different concentrations. The method used is descriptive, where data are shown as mean ± STD. The results showed that P. acidilactici, L. ca-sei, and L.monocytogenes can survive at a rate of NaCl 0-3%; NaNO2 0-100 ppm; NaNO3 0-200 ppm; liquid smoke 0-4%; pH 3 - 5.6; and the incubation temperature of 5-50 °C.


2016 ◽  
Vol 34 (No. 5) ◽  
pp. 391-396 ◽  
Author(s):  
Paszczyk Beata ◽  
Brandt Waldemar ◽  
Łuczyńska Joanna

The effect of the applied starter cultures and storage time of fermented milk drinks on the content of cis-9, trans-11 octadecadienoic acid (CLA), as well as trans isomers of C18:1 and C18:2 acids were evaluated. The analysed fermented milk drinks were produced by the thermostat method and with three different starter cultures. Analyses were carried out for freshly produced fermented milk drinks and for stored drinks (analyses after 6, 13, and 21 days of storage). The study demonstrated that the type of applied starter culture and storage time affected the content of CLA and of trans isomers of C18:1 acid in fermented milk drinks. Among the starter cultures applied, only the Ceska-star Y508 culture caused a significant increase in CLA content in the stored fermented milk drinks. The mean content of CLA in fresh drinks reached to 3.60 mg/g fat. The significantly higher CLA contents (3.85 and 3.89 mg/g fat) were found in drinks after 6 and 13 days of storage, respectively. The content of trans isomers of C18:1 acid in fresh products was 15.92 mg/g fat. In drinks analysed after 6 days of storage it was 17.14 mg/g fat.


1999 ◽  
Vol 62 (7) ◽  
pp. 808-810 ◽  
Author(s):  
MARISA S. GARRO ◽  
GRACIELA F. de VALDEZ ◽  
GUILLERMO OLIVER ◽  
GRACIELA S. de GIORI

The refrigerated shelf life of soymilk fermented with single cultures of Lactobacillus fermentum, L. casei, Streptococcus salivarius subsp. thermophilus, and Bifidobacterium longum was evaluated. During storage at 4°C for 28 days, the stability of the microflora differed markedly among the starter cultures. After 28 days, the average numbers of S. salivarius subsp. thermophilus decreased by two log cycles to 6.0 × 107 CFU/ml, whereas those of L. casei increased gradually by more than two log cycles to 4.6 × 109 CFU/ml. Numbers of B. longum and L. fermentum remained moderately high (8.7 × 108 CFU/ml and 3.7 × 108 CFU/ml, respectively) even after 28 days of storage. S. salivarius subsp. thermophilus and L. casei continued to metabolize sucrose during the storage period, but the pattern of consumption was different among the strains. The other starter cultures did not seem to have significant activity (P > 0.05) on the residual sugars. In most cases, L(+)-lactate predominated.


1939 ◽  
Vol 10 (1) ◽  
pp. 120-132 ◽  
Author(s):  
H. R. Whitehead ◽  
G. J. E. Hunter

Single-strain cultures of streptococci used as “starters” in Cheddar cheese manufacture in New Zealand frequently suffered failure due to the apparently spontaneous appearance of bacteriophage. The trouble was cured at the Institute experimental factory by increasing the inoculum used in the starter culture from about 0·2% to 1·0–1·6%. The culture then showed a regular activity in the cheese vat from day to day for long periods of time. Field trials during the past two years have indicated that single strain cultures can be maintained for long periods also in commercial factories if the correct technique is practised.The theory is postulated that the effect of heavy inoculation in eliminating the spontaneous appearance of bacteriophage is due to the more rapid growth of the streptococci when they are transferred to each new batch of milk, i.e. to the shortening of the lag period. Bacteriophage tends to appear whenever the lag period is prolonged as a result of light inoculation, low incubation temperature, and aeration or ageing of the milk medium. Until more is known of the nature of phage it is not possible to suggest why a prolonged lag period in the initiation of growth should favour the appearance of phage.Under commercial conditions failures of starters occur from time to time due to faulty technique which permits the entry into cultures of extraneous phage. The source of the contamination is most probably the whey from cheese vats, since it has been shown that phage commonly occurs in the whey even in vats where acid develops quite normally within the the cheese curd. A recent case of failure, which appears to be due to some milk abnormality, indicates that there are some milk supplies in which the heavy inoculation technique described in this paper is not completely effective in preventing the appearance of bacteriophage.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Florencia Frau ◽  
Graciela Font de Valdez ◽  
Nora Pece

The local cheese factories currently use bovine commercial starter cultures, and the spreadable cheese process is not standardized. A detailed understanding of the effect of pasteurization temperature, starter culture, and incubation temperature must allow producers to optimize the process, increase cheese yield, and improve the quality of the final product. The main objective of the study was to describe the preparation method of spreadable goat cheese and investigate the effects of specific processing conditions (pasteurization temperature, starter culture, and incubation temperature) on the composition, yield, rheology, and sensory characteristics of the final product. Results showed the impact of pasteurization temperature, starter culture, and incubation temperature on spreadable goat cheese. The results indicated that it is possible to improve cheese yield, rheological properties, and sensory analysis when milk is pasteurized at 75°C for 30 minutes; cheese yield can also be improved by lowering incubation temperature to 37°C. Cheeses made with autochthonous starter culture showed better sensory characteristics and higher pH compared to the cheeses made with commercial culture.


2021 ◽  
Author(s):  
Monika Stojanova ◽  
◽  
Olga Najdenovska ◽  
Dragutin Đukic ◽  
◽  
...  

The aim of this paper is to monitor the influence of two starter cultures on the microbiological stability of Macedonian traditional sausage. The research covered three variants: Control variant; Variant 2: with addition of starter culture CS-300; Variant 3: with addition of starter cultures CS-300 and BLC-78. The total bacteria count and Lactobacillus sp. in all three variants decreases compared to the initial value. There is no presence of Escherichia coli and Enterobacteriaceae.Starter culture CS-300 is recommended, while better stability of the microflora is achieved during the storage period, as well as a good quality. At the same time, the use of nitrite salt is eliminated, which results in getting a safe product.


2014 ◽  
Vol 1010-1012 ◽  
pp. 1789-1792
Author(s):  
De Bao Wang ◽  
Li Hua Zhao ◽  
Fan Yang ◽  
Mei Jun Li ◽  
Ri Na Su ◽  
...  

These sausages were manufactured with mutton and tail fat by starter culture. The microbiological of fermented mutton sausages were evaluated to determine their quality characteristics during ripening and storage. Two groups of fermented sausages manufacture using the same technology were named control group (CO) and starter culture group (SC). In this study, Lactic acid bacteria counts in sausages made with combinations of starter cultures increased to 8 logcfu/g. The total bacteria counts in the SC were lower (P < 0.05) than in the control (CO) after drying and storage time. During ripening, total bacterial counts in the SC were 7logcfu/g, which was significantly lower (p<0.05) than in the CO. The Micrococci-staphylococci counts of the SC were 6 logcfu/g and significantly lower (P < 0.05) than of the CO during ripening.


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