NIZO Improves Flavour Formation with New Genomics Tools

Correlation of whole genome transcriptome data obtained under different fermentative conditions to stress phenotypes is expected to reveal additional genes involved in robustness.

Aug 18 2011 --- With recently developed technology, NIZO food research can select and optimize lactic acid bacteria for flavour formation but also robustness to withstand industrial processing and gastrointestinal conditions. These technologies build on tools generated within precompetitive networks such as TI food and Nutrition (TIFN) and the Kluyver Centre for Genomics of Industrial Fermentation (KC), and are directly  applied  for and with industry at NIZO food research.

Full genome sequences of industrially relevant bacteria can nowadays be routinely determined and specific differential characteristics of these strains can be correlated to the absence/presence of genes. Alternatively, one strain can be differentially cultured and full-genome transcriptome profiles can be correlated to industrially relevant characteristics. These technologies have been made possible by applying tools developed by NIZO and academic partners within the framework of KC and TIFN.

This strategy has so far led to the discovery of genes important for the probiotic effect and the gastrointestinal survival of the probiotic organism Lactobacillus plantarum. Remarkably, differential fermentation resulted in distinct gastrointestinal survival characteristics varying by as much as 10,000,000-fold, pinpointing the importance of optimized fermentation conditions for maximal functionality. Similarly, genes important for flavor formation and robustness against industrial processing of the cheese starter culture Lactococcus lactis were identified.  During production, industrial processing and storage, it is essential that starter cultures remain viable and active. Spray drying is one of the methods used in industry to dry starter cultures and during this process L. lactis encounters heat and oxidative stress. Using a gene-trait matching strategy, a specific set of genetic loci could be correlated to both observed stress survival phenotypes. Additionally, correlation of whole genome transcriptome data obtained under different fermentative conditions to stress phenotypes is expected to reveal additional genes involved in robustness.

According to NIZO expert Peter Bron, scientific director of the lactic acid bacteria programme within KC and senior scientist in TIFN, the translation of tools developed in these collaborative programmes to practical solutions for industry at NIZO illustrates the success and industrial relevance of these programmes. “In a recent review of the KC the panel expressed their confidence in our ability to “deliver on the scientific promises, of which some indeed already have been turned into reality [unquote]”.

The collaborative programme allows industry to optimize their culture conditions for maximized performance of currently used cultures, and paves the way for simple selection of enhanced food bacteria with improved characteristics by high throughput screening of culture collections.