To improve the gel properties of liquid whole egg by short-term lactic acid bacteria fermentation

During a 15-month period, samples of commercially pasteurised liquid whole egg (LWE) were tested for the presence of spoilage microflora. The total bacterial counts were 2.2 ± 0.6 log CFU/g and total lactic acid bacteria (LAB) counts were 1.9 ± 0.6 log CFU/g. Enterobacteriaceae were detected in 2 samples. Out of the tested samples, 45 LAB were isolated and identified, with 30 strains identified as Enterococcus faecium, 12 as Enterococcus faecalis, and 3 as Lactobacillus paracasei subsp. paracasei. All strains, except 6 strains of E. faecium, possessed lipolytic activity. All the E. faecalis strains and one strain of E. faecium showed a high proteolytic activity, while moderate proteolytic activity was shown by 3 lactobacilli strains. Minimum inhibitory concentration (MIC) of nisin and Micocin X was measured against groups of isolated strains, and ranged from 10.4 µg/ml to 41.7 µg/ml for nisin and from 0.2 mg/ml to 1.6 mg/ml for Micocin X. The LWEs supplemented with 6.25 mg/l of nisin or with 500 mg/ml of Micocin X were pasteurised at 65°C for 2.5 minutes. The shelf life of LWE with the addition of nisin or Micocin X stored under refrigerator conditions was extended by a minimum of 5 weeks.

Download Full-text

Effects of short-term fermentation with lactic acid bacteria on egg white: Characterization, rheological and foaming activities

Food Hydrocolloids ◽

10.1016/j.foodhyd.2019.105507 ◽

2020 ◽

Vol 101 ◽

pp. 105507 ◽

Cited By ~ 2

Author(s):

Yawen Jiang ◽

Jie Jia ◽

Dandan Xiong ◽

Xueming Xu ◽

Yanjun Yang ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Egg White ◽

Short Term

Download Full-text

A Relation between Exopolysaccharide from Lactic Acid Bacteria and Properties of Fermentation Induced Soybean Protein Gels

Polymers ◽

10.3390/polym14010090 ◽

2021 ◽

Vol 14 (1) ◽

pp. 90

Author(s):

Xiaoyu Yang ◽

Jiao Feng ◽

Qianqian Zhu ◽

Rui Hong ◽

Liang Li

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Water Distribution ◽

Soybean Protein ◽

Production Capacity ◽

Gel Properties ◽

Texture Profile ◽

Protein Gel ◽

Protein Gels ◽

Α Helix

Exopolysaccharide (EPS) producing lactic acid bacteria (LAB) is considered to be an effective texture improver. The effect of LAB strains (different EPS production capacity) on physicochemical properties (texture profile, water distribution, rheological properties, and microstructure), protein conformation, and chemical forces of soybean protein gel was investigated. Correlations between EPS yield and gel properties were established. Large masses of EPS were isolated from L. casei fermentation gel (L. casei-G, 677.01 ± 19.82 mg/kg). Gel with the highest hardness (319.74 ± 9.98 g) and water holding capacity (WHC, 87.74 ± 2.00%) was also formed with L. casei. The conversion of β-sheet to α-helix, the increased hydrophobic interaction and ionic bond helped to form an ordered gel network. The yield was positively correlated with hardness, WHC, A22, viscoelasticity, and viscosity, but negatively correlated with A23 (p < 0.05). The macromolecular properties of EPS (especially the yield) and its incompatibility with proteins could be explained as the main reason for improving gel properties. In conclusion, the EPS producing LAB, especially L. casei used in our study, is the best ordinary coagulate replacement in soybean-based products.

Download Full-text

Clustering of Streptococcus thermophilus Strains to Establish a Relation between Exopolysaccharide Characteristics and Gel Properties of Acidified Milk

Foods ◽

10.3390/foods8050146 ◽

2019 ◽

Vol 8 (5) ◽

pp. 146 ◽

Cited By ~ 8

Author(s):

Georg Surber ◽

Susann Mende ◽

Doris Jaros ◽

Harald Rohm

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Streptococcus Thermophilus ◽

Starter Cultures ◽

Extracellular Polysaccharides ◽

Gel Properties ◽

Fermentation Time ◽

Thread Length ◽

Acid Gel ◽

Fermented Dairy

In situ produced extracellular polysaccharides (EPS) from lactic acid bacteria are generally known to affect the texture of fermented dairy products; however, the interplay between EPS and product properties is still poorly understood. The aim of this study was to establish a relationship between concentration and properties of EPS, and gel formation of milk analysed by noninvasive Multispeckle Diffusing Wave Spectroscopy. Twenty Streptococcus thermophilus strains were classified with respect to EPS concentration (8–126 mg GE/kg) and ropiness (thread length: 15–80 mm). Five groups identified by cluster analysis demonstrate the high strain-to-strain variability even within one species of lactic acid bacteria. Results from acidification and gelation experiments averaged per cluster indicate that fermentation time and gel stiffness is higher for strains that produce ropy EPS. A further increase in gel stiffness was detected for strains that also produced cell-bound EPS, which underlines the importance of both ropy and cell-bound EPS for improving acid gel properties. The results may be helpful for a proper selection of EPS-producing starter cultures.

Download Full-text