Effect of season on microbial and chemical characteristics of milk and yoghurt from sheep

2014 ◽  
Vol 54 (8) ◽  
pp. 1091 ◽  
Author(s):  
Razzagh Mahmoudi ◽  
Reza Norian ◽  
Mohammad Reza Pajohi-Alamoti ◽  
Javad Aliakbarlu

The quality and hygienic status of milk are of importance for both dairy industries and consumers. In the present study, the effect of season on the quality and microbial properties of sheep milk and yoghurt produced from sheep milk were surveyed. In total, 30 sheep-milk samples were collected from January to August 2011, and yoghurt was produced from these samples. The fat content, titratable acidity and pH showed changes across the year. Seasonal variation was found to have a significant (P < 0.05) effect on nitrogen components, particularly crude protein, non-casein protein and non-protein nitrogen contents, fat content, pH and titratable acidity. Sensory analysis showed that the quality of yoghurt samples produced in winter was higher than that of yoghurt produced in summer (P < 0.05). This work showed the effect of season on chemical and sensory properties of sheep milk and yoghurt in Qazvin, Iran.

Author(s):  
Fausat Adeola Abdulrahman ◽  
Emiade Sanmi

The study aims at determining the physicochemical, proximate composition and the total viable count of Staphylococcus aureus in ‘Nono’ and yoghurt samples in Kaduna, Nigeria.Three hundred and eighty-four (384) fermented milk samples (Nono and yoghurt) were obtained from different selling points and were evaluated for the occurrence of S. aureus. The physicochemical and proximate analyses (pH, total titratable acidity, moisture content, ash content, protein content, and fat content) were determined. The results of the analyses showed that Nono had pH range of 3.56-3.61, total titratable acidity: 0.71-1.72, moisture content: 82.23-83.87%, ash content: 0.30-0.31%, crude protein content: 1.50-1.61%, crude fat content: 0.35-0.38 %. For yoghurt, the pH ranged from 3.76 -3.82, total titratable acidity: 1.10 -1.15, moisture content: 77.76-80.06%, ash content: 0.68- 0.70%, crude protein content: 3.40-3.45% and crude fat content: 1.76-1.79% from all the study areas. One hundred and four of the total samples were contaminated with S. aureus. Out of the 104 isolates of S. aureus that were isolated and identified, 88 were coagulase positive S.aureus. The Microgen Staph ID kit (Oxoid) was used to further confirm the characteristics of the 60 isolates of the coagulase positive S. aureus. The kit confirmed 43 isolates as S. aureus, the results indicated the presence of S. aureus in the milk samples which is of public health importance, as this can contribute to food-borne intoxication which can lead to food poisoning. There is a need for proper pasteurisation of raw milk to help eradicate S. aureus infection before human consumption.


2001 ◽  
Vol 2 (2) ◽  
pp. 22-25
Author(s):  
Yusdar Zakaria

ABSTRACT.  A study of pyisical properties and quality of yogurt with Lactobacillus bulgaricus as a starter has been doon. Objectives of this study is to know how many percent starter of L. bulgaricus in yogurt to decrease suscepetibility to syneresis and to increase quality of yogurt. Yogurt was analyzed for susceptibility to syineresis, titratable acidity and content of crude protein and crude fat. Syinerisis of yogurt was evaluated according to centrifugal methods of Halwarkar and Kalab. The result of the study showed that yogurt with 2.5-10 % L. bulgaricus as a starter are not have any effect of susceptibility to synerisis and content of crude fat, but centripuged at 250-1000 rpm. Had significantly different (0.01) on susceptibility to synerisis. On the other hand the increasing of centrifuge rotation, increase susceptibility to synerisis. The starter of 5-10% L. bulgaricus used in yogurt able to increase titratable acidity and content of crude protein. The yogurt prepared by 10% L. bulgaricus had the highest score (3.88%) of crude protein, although there is no significant differences with yogurt using 7.5% L. bulgaricus.


Author(s):  
A. C. Honorato ◽  
C. B. R. Dias ◽  
E. B. Souza ◽  
I. R. B. Carvalho ◽  
K. S. M. Sousa

<p>Este trabalho teve como objetivo avaliar os parâmetros físico-químicos de polpas de fruta produzidas e comercializadas na cidade de Petrolina-PE, tendo como referência a Instrução Normativa nº 1, de 7 jan. 2000, do Ministério da Agricultura que define as características físicas e químicas estabelecendo limites mínimos e máximos específicos para cada polpa de fruta. Foram avaliadas duas marcas (1 e 2) de polpas de abacaxi, cacau, caju, graviola, maracujá e umbu, analisadas quanto aos parâmetros de pH, sólidos solúveis totais (SST), acidez total titulável (ATT), ácido ascórbico, relação SST/ATT e sólidos totais. Os resultados permitem inferir que a marca 2 apresentou qualidade superior na maioria dos parâmetros avaliados quando comparado com a marca 1. Entretanto para alguns sabores de polpa as duas marcas não atenderam os valores padrões. Entre as polpas o único sabor que apresentou os padrões exigidos foi a polpa de caju em ambas as marcas, e a que apresentou resultado de pior qualidade diante dos padrões foi a polpa de maracujá principalmente da marca 1. Dessa forma constata-se que há grandes variações entre as marcas, e entre alguns parâmetros, o que compromete a qualidade das polpas, prejudicando assim o consumidor.</p><p align="center"><strong><em>Physicochemical parameters of fruit pulps produced in Petrolina – PE</em></strong></p><p><strong>Abstract</strong><strong>: </strong>This study aimed to evaluate the physicochemical parameters of fruit pulps produced and marketed in the city of Petrolina-PE, with reference to the Instruction Nº 1 of 7 January 2000 of the Ministry of Agriculture, which defines the physical and chemical characteristics setting minimum and maximum limits specific to each fruit pulp. We evaluated two brands (1 and 2) of pineapple, cocoa, cashew, soursop, passion and umbu fruit pulp, analyzed for pH, total soluble solids (TSS), total titratable acidity (TTA), ascorbic acid, TSS / TTA and total solids parameters. Results show that the brand 2 showed superior in most evaluated parameters when compared to the brand 1. However, for some pulp flavors of both brands did not reached the standards values. Among the pulps, the only flavor that presented the required standards was the cashew pulp in both brands, and presented the results of lower quality on the standards was the passion fruit pulp mainly brand 1. Thus, it appears that there are great variations between brands and between some parameters, which compromises the quality of the pulp, thus impairing the consumer.</p>


Author(s):  
А.Ю. Червяков ◽  
Е.В. Тюкина ◽  
Д.В. Бочкарёв ◽  
Н.В. Смолин ◽  
А.Н. Никольский ◽  
...  

Исследования влияния системного применения гербицидов при ресурсосберегающей обработке почвы на качественные показатели зерна кукурузы проведены на землях ОАО «Агросоюз» Рузаевского района Республики Мордовия в 2014–2016 годах. Установлено, что обработка посевов гербицидом «Дублон» (1,2 л/га) и баковой смесью «Дублон Голд» (0,07 кг/га) + «Балерина» (0,25 л/га) способствовала повышению содержания сырого протеина в зерне до 93,67 и 94,97 г/кг соответственно. Анализ содержания жира в зерне кукурузы выявил, что наибольшим оно было в контрольном варианте. Внесение препаратов «Дублон», «Дублон Супер», «Дублон Голд» и их сочетаний с «Балериной» статистически достоверно снижало концентрацию жира. Используемые пестициды достоверного влияния на увеличение содержания крахмала в зерне кукурузы не оказывали. Содержание клетчатки снижалось: при использовании препаратов «Дублон Супер», «Дублон Голд» и «Дублон» + «Балерина» её уровень был ниже контроля на 5–10%. В результате увеличения урожайности зерна кукурузы за счёт высокой эффективности гербицидов во всех вариантах опыта возрастал сбор протеина с 0,51 до 0,75 т/га. В исследованиях также установлено, что в вариантах с применением баковых смесей гербицидов «Дублон + «Балерина» и «Дублон Голд» + «Балерина» по сравнению с контролем валовой сбор крахмала, сахара, сырого жира был наивысшим. Между содержанием в зерне кукурузы сырого протеина, клетчатки, сырого жира, сахара и крахмала наблюдалась достоверная слабая положительная зависимость. Гербициды группы «Дублон» повышали концентрацию сахара до 32,6–33,3 г/кг. В результате повышенного содержания жира в зерне кукурузы уровень валовой энергии был наивысшим в контрольном варианте — 19,37 МДж/кг. При внесении гербицидов она снижалась вследствие повышения доли белка в органическом веществе зерна кукурузы. The investigation was carried out at the OAO “Agrosoyuz” (the Ruzaevskiy district, Republic of Mordovia) in 2014–2016. The effect of herbicide application was tested on maize under minimum tillage. Plant treatment with “Dublon” (1.2 l ha-1) as well as the mixture of “Dublon Gold” (0.07 kg ha-1) and “Balerina” (0.25 l ha-1) increased crude protein in grain up to 93.67 and 94.97 g/kg, respectively. The highest fat content was observed in the control. Application of “Dublon”, “Dublon Super”, “Dublon Gold” and their mixtures with “Balerina” significantly reduced fat accumulation. The preparations had no significant impact on starch formation. “Dublon Super”, “Dublon Gold” and “Dublon” + “Balerina” reduced fiber content by 5–10%. As a result of herbicide use grain productivity increased, and protein yield raised from 0.51 to 0.75 l ha-1. Mixtures of “Dublon” + “Balerina” as well as “Dublon Gold” + “Balerina” provided the highest gross yields of starch, sugar, and crude fat. Significant positive correlation was observed among crude protein, fiber, fat, sugars and starch. The “Dublon” herbicides positively affected sugar concentration up to 32.6–33.3 g/kg. Due to higher fat content gross energy yield was the highest in the control — 19.37 MJ/kg. Herbicide treatment reduced gross energy due to the higher protein content in grain organic matter.


1996 ◽  
Vol 59 (9) ◽  
pp. 984-987 ◽  
Author(s):  
A. N. MUTUKUMIRA ◽  
S. B. FERESU ◽  
J. A. NARVHUS ◽  
R. K. ABRAHAMSEN

Chemical and microbiological analyses were carried out on 10 samples of raw milk collected over 6 months from the Nharira/Lancashire Milk Collection Center. The milk center is run by smallholder farmers. The purpose of the study was to evaluate the quality of the raw milk delivered to the milk collection center. The average chemical characteristics of the milk were (%): titratable acidity expressed as lactic acid, 0.21; total protein, 3.19; fat, 3.52; total solids, 11.76; and solids not fat, 8.25; the pH varied from 6.15 to 6.65. There were large variations in the microbiological composition of the raw milk with total aerobic counts ranging from 6.2 × 103 to 7.8 × 107 CFU/ml, coli forms from 3.2 × 102 to 2.3 × 105, and lactic acid bacteria from less than 1 × 103 to 2.9 × 106 CFU/ml. Yeasts and molds were less than 100 CFU/ml in 7 of the 10 samples analyzed.


2008 ◽  
Vol 53 (No. 2) ◽  
pp. 55-63 ◽  
Author(s):  
J. Kuchtík ◽  
K. Šustová ◽  
T. Urban ◽  
D. Zapletal

The evaluation of the effect of the stage of lactation on milk composition, its properties and the quality of rennet curdling was carried out over the period of three successive years using milk samples (<I>n</I> = 162) obtained from a total of 27 ewes of the East Friesian (EF) breed, reared on a small sheep farm in Juřinka in the region of Wallachia. The stage of lactation had a highly significant effect on the contents of all milk components. However, only the contents of total solids (TS), solids non-fat (SNF), fat (F), protein (P) and casein (CN) gradually increased with the advancement of lactation. The stage of lactation also had a highly significant effect both on all the properties of milk and the rennet curdling quality (RCQ). All phenotypic correlations between the particular contents of TS, SNF, F, P, CN and urea nitrogen (UN) were positive and high (<I>P</I> ≤ 0.001). On the other hand, all phenotypic correlations between milk yield and particular contents of TS, SNF, F, P, CN and UN were negative and high (<I>P</I> ≤ 0.001). The majority of phenotypic correlations between rennet clotting time (RCT) and the other particular parameters was insignificant. However, the phenotypic correlations between lactose (L) and RCT and between pH and RCT were positive and high (<I>P</I> ≤ 0.001) whereas the phenotypic correlation between titratable acidity (TA) and RCT was negative and high (<I>P</I> ≤ 0.001). The majority of phenotypic correlations between the rennet curdling quality (RCQ) and the other particular parameters was insignificant. Nevertheless, the phenotypic correlations between pH and RCQ and between RCT and RCQ were positive and high (<I>P</I> ≤ 0.001) whereas the phenotypic correlation between TA and RCQ was negative and high (<I>P</I> ≤ 0.001).


2017 ◽  
Vol 8 (1) ◽  
pp. 93
Author(s):  
Francisco Sidene Oliveira Silva ◽  
Eduardo Castro Pereira ◽  
Vander Mendonça ◽  
Francisco Mickael De Medeiros Câmara ◽  
Gustavo Alves Pereira ◽  
...  

Aiming to evaluate the postharvest quality of ‘Roxo de Valinhos’ fig fruits grown in semi-arid conditions, this experiment was carried out in November, 2014, where fig fruit variety ‘Roxo de Valinhos’ were harvested from plants located at the didactic orchard of the Federal Rural University of Semi-Arid (UFERSA), Mossoró-RN, Brazil. Fruits were randomly harvested from 30 fig plants, spaced 2 m x 1.5 m, with 2 years old, according to three the fruit development stages (50%, 75% and 100% mature). The fruits were analyzed in Postharvest Physiology Laboratory, where the physical and chemical characteristics were evaluated, using 10 fruits for each stage. The evaluated characteristics were: weight, length, diameter, firmness, soluble solids, pH, titratable acidity and vitamin C. For the physical characteristics, fruits 100% mature presented the best results for weight, length and diameter, except for firmness which in fruits 50% mature presented the best results. For the chemical characteristics, only the soluble solid variable was signiicant and fruits 100% mature showed the best result, in this way, the fig tree ‘Roxo de Valinhos’ achieved the postharvest fruit quality and is viable for the semiarid region of the Rio Grande Norte State.


2016 ◽  
Vol 45 (2) ◽  
pp. 73-78 ◽  
Author(s):  
MS Uddin ◽  
MR Habib ◽  
MA Islam ◽  
S Afrin ◽  
MH Rashid

The present study was conducted to know the chemical qualities and adulteration of fresh raw milk collected from local markets (Bhangnamari bazaar, Sutiakhali bazaar, Vabokhali bazaar, Shombhuganj bazaar and Mymensingh sadar bazaar) of Mymensingh sadar, Bangladesh. Milk samples were analyzed for chemical parameters (contents of acidity, total solids, solids-not-fat, fat, protein and ash) and adulteration (presence of formalin, sugar or starch). Also, lactometer reading was recorded to monitor the specific gravity of the collected milk samples. Result showed that the specific gravity of milk from different sources differed non-significantly. The total solids, fat and protein contents of all the samples were in normal range except the milk fat content collected from Shombhuganj bazaar (32.66±4.04 g/Kg) and Mymensingh sadar bazaar (30.66±4.51 g/Kg) which had less (p<0.01) than the minimum legal standard of milk fat (35.00 g/Kg). The solids-not-fat content of the milk samples collected from Bhangnamari bazaar (72.93±8.78 g/Kg) and Vabokhali bazaar (79.33±6.81 g/Kg) were less than that from Mymensingh sadar bazaar (95.67±11.72 g/Kg). Developed acidity was detected in the samples from Bhangnamari bazaar (0.180±0.03), Sutiakhali bazaar (0.187±0.04%) and Mymensingh sadar bazaar (0.180±0.02%), while other samples were found to the fresh (0.150-0.157%). All of the adulteration tests showed negative results. The results suggested that though there were some fluctuations in quality among the bazaars regarding the standard of parameters, the raw milk samples were of acceptable quality.Bang. J. Anim. Sci. 2016. 45 (2): 73-78


2018 ◽  
Vol 5 ◽  
pp. 7-10
Author(s):  
Astha Parajuli ◽  
Prasiddhi Rimal ◽  
Rujisha Maharjan ◽  
Richa Chaudhary ◽  
Shashi Bhusan Chaturwedi

Objectives: This study was carried out to evaluate physiochemical, adulteration and microbial quality of milk sold in Kathmandu Valley. Methods: The study was carried out in Microbiology Laboratory of DAV College. The total of 20 milk samples randomly collected from different places of the valley including 10 pasteurized milk sample and 10 were raw milk sample, were processed for Physiochemical and Microbiological analysis. Result: The laboratory analysis revealed that the pasteurized samples has less mesophilic count as well as coliform count than raw milk samples. About 55% milk samples showed neutralizer test positive and 10% of milk samples were found to be positive for sugar test. However, none of the samples were found to contain starch as an adulterant. The average fat content of milk samples of Kathmandu Valley was 3%. Fat percent was significantly different among different sources of sampling points. The highest milk fat content value was recorded at Pulchowk (3.7%). The average SNF of Kathmandu Valley was 7% in which the pasteurized sample had the highest average SNF (7.3%) and the raw milk had lowest average SNF (6.8%). Conclusion: The significant variation in the physiochemical properties and microbial properties of the milk samples showed that people should be conscious about the consumption of market milk.  


2020 ◽  
Vol 8 (2) ◽  
pp. 820
Author(s):  
Luis Carlos Vinhas Itavo ◽  
Camila Celeste Brandão Ferreira Itavo ◽  
Alexandre Menezes Dias ◽  
Gumercindo Loriano Franco ◽  
Maria Da Graça Morais ◽  
...  

Dry season reduces the quantity and quality of forage available for cattle. To guarantee the quantity, deferred grazing is a good alternative, however supplementation is necessary to complement the nutritional quality of the diet. Therefore, this work evaluated the inclusion of nutritional additives (virginiamycin and salinomycin) in supplements provide to Nellore steers during growth phase on deferred pasture during the dry season. One hundred and twenty castrated steers with averaging weight 280.40 (±19.59) kg were distributed into groups with 20 animals each in six paddocks with 20 hectares each of Brachiaria brizantha cv. MG4 deferred by 60 days. The total experimental period was 120 days, with rotating groups in paddocks each 15 days. The treatments consisted in a protein-energy-mineral supplement, with 30% crude protein (CP), 40% total digestible nutrient (TDN) containing three different non-protein nitrogen (NPN) sources and with or without nutritional additive. The treatment containing virginiamycin showed better performance (P <0.05) than the treatments with salinomycin and without additive (negative control). The revenue from treatment with virginiamycin (US$ 97.28) was 7.6% and 9.8% higher than of the treatments without additive (US$ 90.41) and with salinomycin (US$ 88.63) respectively. Virginiamycin used in nitrogen supplements during the growing phase of Nellore steers on deferred pasture maintains performance in dry season and increases net margin per animal.


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