metabolomicdiscoveries_flavour_profiler_mangoMango is an exotic fruit, which grows mainly in warmer climates and is shipped to export markets around the world. Mangos often need to be harvested early to arrive in ripeness stage in the supermarket. The fruit has therefore little time on the plant to develop flavor. Also, the skin color of a mango is no indication of ripeness and flavor. Therefore the consumer has to test the firmness of each mango. This is undesirable for both consumer and the quality of the fruit.

To understand mango flavor and its correlation with ripeness, Metabolomic Discoveries has used its Flavor Profiler™ platform to screen for flavor components contributing to ripe and unripe mangos. The ultimate goal of this study is to define metabolites measurable on the skin of a mango to develop a simple test indication for ripeness and as such flavor.

A consumer panel scored the taste and degree of ripeness of 18 mangos. The Flavor Profiler™ platform was employed to screen for the metabolic composition and to develop a mathematical model linking taste and ripeness with the metabolic profiles. The built model shows that unripe can clearly be separated from ripe mangos (Figure 1).

Furthermore, taste metabolites differentiating good from bad taste can be clearly separated. When this model is fed with new mango samples, it allows to predict with a chance of over 80% their ripeness and taste (Figure 2).

Further in depth analysis of the data and studying the basis of the predictive model reveal that mainly sugar and sugar conjugates contribute to a ripe and flavorful mango experience, while organic acids and amino acids determine a rather unripe and negative taste experience.

CONCLUSION
Mango flavor can be linked to a set of metabolites and clearly linked to the degree of ripeness. With this knowledge it is only a little step to develop a consumer and mango friendly ripeness and flavor test.

MD_leaflet_flavour_figure_1           MD_leaflet_flavour_figure2

Figure 1. Ripeness and Taste Model                                                  Figure 2: Taste prediction model. 0, bad taste; 5 excellent taste.

Stable Isotope Labelling

Stable isotopes are a useful tool to track biomolecules in vivo and identify routes of those compounds. Stable isotopes are advantageous over radioactive isotopes as they are not harmful, can be handled without extensive safety measures and occur also naturally. Our comprehensive
metabolomics platform allows us to track all potential routes the labelled molecules takes and thus facilitates the identification and optimization of biosynthetic pathways.

Stable isotopes are a useful tool to track biomolecules in vivo and identify routes of those compounds. Stable isotopes are advantageous over radioactive isotopes as they are not harmful, can be handled without extensive safety measures and occur also naturally. Our comprehensive metabolomics platform allows us to track all potential routes the labelled molecules takes and thus facilitates the identification and optimization of biosynthetic pathways (Figure 1).

MD_mzpattern_stableisotopes

Figure 1. Mass spectral pattern of a 13C labelled molecule versus an unlabelled molecule.

Pathway Discovery

Metabolic pathways are diverse and highly complex. Every organism has evolved their own survival mechanisms. These mechanisms often include the synthesis of small molecules to attract, repel, harm, kill or feed other organisms. To drive biosynthesis to the desired product the pathway and interconnectivity needs to be understood.

In a case of industrial aroma production we pinned down the major biosynthetic route and the responsible genes of phenylethanol (Rose aroma) biosynthesis. Phenylethanol is derived from phenylalanine, though the exact pathway was unknown. 13C-labelled Phenylalanine was brought into the system to identify the routes leading to phenylethanol.

MD_MFE_3D

Figure 2. Molecular Enrichment of 13C in identified metabolites.

 

By use of various analytical and molecular tools. The major route of Phenylethanol biosynthesis could be identified. The first step is a decarboxylation leading to phenethylamine in a consecutive reaction a deamination reaction occurs leading to phenacetaldehyde. The last reaction is catalysed by a reductase and leads to phenylethanol (Figure 3).

MD_PEtOH_Pathway

Figure 3. Major biosynthetic pathway of phenylethanol.

Metabolite classes covered for aroma:
Aldehydes
Alcohols
Amines
Aromatics
Esters
Ketones
Lactones
Terpenes
Thiols
Metabolite classes covered for taste: 
Sugars
Organic acids
Amino acids
Polyols/Sugar alcohols
Sugar phosphates
Sweetners
Bitter compounds