Isolation and characterisation of exopolysaccharide-producing Weissella and Lactobacillus and their application as adjunct cultures in Cheddar cheese

This study characterised exopolysaccharide-producing lactic acid bacteria and examined their potential for use in Cheddar cheese manufacture. Two strains were chosen for incorporation as adjunct cultures in Cheddar cheese manufacture: namely, the homopolysaccharide-producers Weissella cibaria MG1 and Lactobacillus reuteri cc2. These strains both produce dextrans with molecular masses ranging from 10⁵ to 10⁷ Da. Both strains were used in the production of miniature Cheddar cheeses that employed a conventional commercial cheese starter culture Lactococcus lactis R604. A cheese was also included that used purified dextran as an ingredient. The W. cibaria strain survived in cheese with levels increasing by 1.5 log cycles over the ripening period. All experimental cheeses (adjunct or exopolysaccharide ingredient) had higher moisture levels compared with the control cheese made using starter alone. Inclusion of the adjunct strains had no detectable negative effects on cheeses in terms of proteolysis.     

Implementation of HACCP system in China: A survey of food enterprises involved

The paper reports the results of the study on HACCP implementation in China based on analyzing the findings of a survey on 27 food enterprises involved. The results indicate that large- and medium-sized food enterprises dominate over the implementation of HACCP system in China. The product types produced by food enterprises in China that implement HACCP system are those with a hold in international market. China’s food enterprises take the implementation of HACCP system as a strategy to gain market competition advantage. The top incentives for China’s food enterprises implementing HACCP system are that HACCP system can provide them more chances to access to new markets, improve product quality and increase market share, showing that the major incentives of HACCP implementation in China are market-oriented.     

Growth and survival of bifidobacteria and lactic acid bacteria during the fermentation and storage of cultured soymilk drinks

The behaviours of the bifidobacteria B. infantis CCRC 14633 and B. longum B6 and of the lactic acid bacteria Lactobacillus acidophilus CCRC 14079, L. bulgaricus CCRC 14009 and Streptococcus thermophilus CCRC 14085 during the fermentation and storage of cultured soymilk drinks were investigated. Soymilk was found to support the simultaneous growth of the bifidobacteria and L. acidophilus or S. thermophilus, but B. infantis and B. longum both had a deleterious effect on the growth of L. bulgaricus in soymilk. Values for pH, ranging from 6·13 to 4·19, and titratable acidity ranging from 0·09% to 0·25% were noted in soymilk after 48 h of fermentation with various combinations of bifidobacteria and lactic acid bacteria. The viable populations of bifidobacteria and lactic acid bacteria decreased rapidly in the fermented soymilk drinks held at 25°C. When sucrose was added, the reduction in numbers were more pronounced, especially for bifidobacteria. However, the numbers of bifidobacteria and lactic acid bacteria showed no marked change in drinks with or without sucrose during storage for 10 days at 5°C.     

Comparison of thermal and non-thermal extraction methods on free and bound phenolics in pomegranate peel

Pomegranate peel is a valuable byproduct for phenolic extraction. However, comprehensive analysis on novel extraction methods is lacking. In this study, free and bound phenolics, extracted by thermal (heating) and non-thermal methods (conventional solvent, high pressure, and ultrasound), were systematically compared by UHPLC-QTOF-MS and UPLC-QQQ-MS. The total content of free phenolics, approximately 10 times to that of bound phenolics, showed no significant difference across different extraction methods. The highest yield of bound phenolics was obtained by heating and high-pressure methods and the composition was closely dependent on the degree of alkaline hydrolysis. Many of bound phenolics obtained by thermal extraction were small molecules. Meanwhile, a greater proportion of larger compounds were obtained by high-pressure extraction, indicating that high pressure was gentler than thermal extraction. Genistin, nicotiflorin and myricetin-3-galactoside were first reported in pomegranate peel. This study provides a solid foundation for purposeful extraction of phenolics from pomegranate peels for industry.