scholarly journals Effect of Source of Heat and Storage Period on Physicochemical and Microbiological Characteristics of Goat Milk

Author(s):  
Abdalla Mohamed Osman Mohamed ◽  
◽  
Elsayed Zubida Elsayed Abdalla ◽  
Nour Abdelazim Ahmed Mohamed ◽  
◽  
...  
2019 ◽  
Vol 86 (3) ◽  
pp. 361-367 ◽  
Author(s):  
Evangelia Zoidou ◽  
Sofia Theodorou ◽  
Ekaterini Moschopoulou ◽  
Lambros Sakkas ◽  
Georgios Theodorou ◽  
...  

AbstractThis research paper addresses the hypothesis that the fortification of goat milk base with whey protein concentrate (WPC) could affect both the textural and the biofunctional properties of set-style yoghurt. The effect of fortification of goat milk base with two different WPCs on thermophilic bacteria counts, proteolysis, physical and biofunctional properties of set-style yoghurts was studied at specific sampling points throughout a 4-week storage period. Fortification and storage did not influence thermophilic counts. Physical properties were affected significantly (P < 0.05) by the composition of the protein and the mineral fraction of the WPC but not by the storage. ACE-inhibitory activity was moderate in accordance to low lactobacilli counts and lack of proteolysis. DPPH-radical scavenging activity, Fe2+-chelating activity and superoxide scavenging activity were high. At 28 d an anti-inflammatory effect was observed, which was not affected by WPC addition.


Mljekarstvo ◽  
2020 ◽  
Vol 71 (1) ◽  
pp. 60-68
Author(s):  
Gizem Şendoğan ◽  

In this study, the content of hippuric and benzoic acid of goat milk kefir produced with commercial lyophilized kefir cultures and kefir grain was investigated. 9 commercial kefir culture and 1 kefir grain were used in production of goat milk kefir. Based on the obtained results, hippuric acid was not found in kefir samples during the storage period, whereas goat milk samples contained hippuric acid (14.8 mg/kg). Benzoic acid levels of kefir samples ranged from 8.5 to 26.6 mg/kg during the 28-day storage period. The highest Lactobacillus and Lactococcus counts were observed in kefir sample produced with kefir grain while this sample was one of the sample containing the lowest (11.2 mg/kg) benzoic acid levels. In conclusion, the research results showed that starter kefir cultures and microbiota used in kefir production and storage period had a significant effect on the formation of benzoic acid levels (p<0.05).


1982 ◽  
Vol 45 (6) ◽  
pp. 527-532 ◽  
Author(s):  
C. A. ROTHENBERG ◽  
B. W. BERRY ◽  
J. L. OBLINGER

Effects of various handling, packaging, temperature-abuse and storage conditions were determined on the microbiological characteristics of beef livers and tongues. These organs were evaluated: (a) initially following slaughter, (b) immediately following the frozen storage period of 2–4 weeks at −29°C and (c) following a simulated shipping-temperature abuse of 24 h at 22–28°C followed by 13 days of storage at −1 ± 0.5°C. Initial counts (log/cm2) of coliforms, coagulase-positive Staphylococcus aureus and Clostridium perfringens ranged from 0.19–1.37. Generally, neither freezing nor temperature-abuse had a significant effect on these microorganisms. Vacuum-packaged beef tongues and livers, generally, had lower bacterial counts than did either naked or polyvinyl chloride film-wrapped products. Generally, it was observed that abusive storage temperatures, in conjunction with the naked and film-wrapped packaging systems, appear to present potential microbial spoilage problems when compared with vacuum packaging.


Membranes ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 301
Author(s):  
Xingjia Li ◽  
Zhi Shi ◽  
Xiuli Zhang ◽  
Xiangjian Meng ◽  
Zhiqiang Huang ◽  
...  

The effect of testing temperature and storage period on the polarization fatigue properties of poly (vinylidene fluoride-trifluoroethylene) (P(VDF–TrFE)) ultrathin film devices were investigated. The experimental results show that, even after stored in air for 150 days, the relative remanent polarization (Pr/Pr(0)) of P(VDF–TrFE) of ultrathin films can keep at a relatively high level of 0.80 at 25 °C and 0.70 at 60 °C. To account for this result, a hydrogen fluoride (HF) formation inhibition mechanism was proposed, which correlated the testing temperature and the storage period with the microstructure of P(VDF–TrFE) molecular chain. Moreover, a theoretical model was constructed to describe the polarization fatigue evolution of P(VDF–TrFE) samples.


Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2339
Author(s):  
So-Yul Yun ◽  
Jee-Young Imm

Age gelation is a major quality defect in ultra-high-temperature (UHT) pasteurized milk during extended storage. Changes in plasmin (PL)-induced sedimentation were investigated during storage (23 °C and 37 °C, four weeks) of UHT skim milk treated with PL (2.5, 10, and 15 U/L). The increase in particle size and broadening of the particle size distribution of samples during storage were dependent on the PL concentration, storage period, and storage temperature. Sediment analysis indicated that elevated storage temperature accelerated protein sedimentation. The initial PL concentration was positively correlated with the amount of protein sediment in samples stored at 23 °C for four weeks (r = 0.615; p < 0.01), whereas this correlation was negative in samples stored at 37 °C for the same time (r = −0.358; p < 0.01) due to extensive proteolysis. SDS-PAGE revealed that whey proteins remained soluble over storage at 23 °C for four weeks, but they mostly disappeared from the soluble phase of PL-added samples after two weeks’ storage at 37 °C. Transmission electron micrographs of PL-containing UHT skim milk during storage at different temperatures supported the trend of sediment analysis well. Based on the Fourier transform infrared spectra of UHT skim milk stored at 23 °C for three weeks, PL-induced particle size enlargement was due to protein aggregation and the formation of intermolecular β-sheet structures, which contributed to casein destabilization, leading to sediment formation.


2020 ◽  
Vol 43 (5) ◽  
pp. 126131 ◽  
Author(s):  
Paula de Almeida Carvalho-Estrada ◽  
Juliana Fernandes ◽  
Érica Benjamim da Silva ◽  
Polyana Tizioto ◽  
Solidete de Fátima Paziani ◽  
...  

2021 ◽  
Vol 34 (1) ◽  
Author(s):  
V. A. Obatolu ◽  
E. A. Adebowale ◽  
F. Omidokun ◽  
E. O. Farinde

This paper compared the chemical (Proximate and mineral), acidity, microbial count and organoleptic properties of yoghurt samples produced from Nigeria locally bred goat and cow milk with commercially retail yoghurt during 14days of refrigerated storage. Yoghurt production was conducted by inoculation of the milk samples at 43oC for 6hrs with 2% of streptococcus thermophillus and lactobacillus bulgarus active culture. The total ash content of yoghurt ranges from 0.23g/100g in the commercial yoghurt sample to 0.84g/100g in yoghurt from goat  milk which is considered significantly higher than that observed for yoghurt from cow milk. The commercially retail yoghurt had a significantly higher (P < 0.05) total solid matter than yoghurt from goat and cow milk. Calcium and phosphorus contents were significantly (P < 0.05) lowest in the commercial yoghurt (0.28%) to a significant higher value of 0.28% in goat milk. A statisitically significant drop in pH values was observed in the commercial yoghurt sample after one and two week storage compared to yoghurt from goat and cow milk. High lactic acid bacteria were observed in yoghurt from cow milk with lactococci group being higher than the lactobacilli group throughout the storage period. The yeast count range from a significant low (P < 05) value of 2.22 cfu/ml-1 in commercial yoghurt sample to 3.22 and 3.24 in goat and cow milk respectively on day zero of storage. By the 7days of storage, the commercially retail yoghurt was significant (P < 0.05) least desirable with respect to colour, taste and overall acceptability while there was no significant difference in the consistency of all the yoghurt samples.


Author(s):  
Muhammad Akhlaq ◽  
Shinawar Waseem Ali ◽  
Ayesha Murtaza ◽  
Muhammad Arshad Javed ◽  
Aftab Ahmad Khan ◽  
...  

2015 ◽  
Vol 39 (3) ◽  
pp. 276-282
Author(s):  
Hêmina Carla Vilela ◽  
Patrícia de Fátima Pereira Goulart ◽  
Kamila Rezende Dázio de Souza ◽  
Ana Carolina Vilas Boas ◽  
Jane Silva Roda ◽  
...  

The arracacha is an alternative of fresh-cut product; however it can be easily degraded after the processing techniques. The objective of this work was to evaluate the useful life of fresh-cut arracacha submitted to two types of cuts and storage, as well as to evaluate the activity of antioxidant enzymes. The roots were selected, sanitized and submitted to two cut types: cubed and grated. Then they were evaluated at 3 times: 0, 3 and 7 days. The cutting in cubes provided higher quality and lower SOD, CAT and APX activity. However, the grated product presented higher PG activity and lower PPO activity. The microbiological safety and the nutritional value were maintained in both cuts during the whole storage period. The useful life, regarding the physicochemical, nutritional and microbiological aspects, can be established at 7 days under refrigeration for fresh-cut arracacha.


Sign in / Sign up

Export Citation Format

Share Document