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Fig. 2a Potato Attribute from Methionine

Results Targeted Analysis

Fig. 2a and 2b. Human sensory (rapid attribute profiling). Matrix has asignificant effect on odour attribute formation. Isoleucine increases malt likeattribute in water ≥ model ≥ liver. Methionine increases potato like attribute in water

> model = liver. n = 12, mean and 95% C.I., letters are Tukey groups (p<0.05).

Odour Formation in Meat and Model Systems Following Flavour Precursor Addition

Proprietary information: Not to be reproduced or distributed without the express consent of Mars Inc. ©Mars 2016

Introduction

Flavour Precursors (FPs) are added to food, before thermal processing togenerate flavours in finished product. Common FPs include amino acids andreducing sugars

Many publications use simple model systems, such as, water to understand odourformation from FPs. But, is water representative of a complex food system?

The odour attribute and odorants in canned liver (with water 25% wt.) weredetermined using the Sensomics approach (Fig. 1)

Fig. 1 (Table 1). Odorants in canned liver were determined by Sensomics.

This work investigates the difference in odour attribute, odorants and volatileorganic compounds (VOCs) generated using FPs when added to canned liverand two model systems: water and a free amino acid reducing sugar model,based on raw liver analysis.

1WALTHAM Centre for Pet Nutrition, Mars Petcare, Waltham-on-the-Wolds, Leicestershire, UK.

2Anatune, Wellbrook Court, Cambridge, Cambridgeshire, UK.

Lewis L. Jones1, James B. Addison1, Nathan Hawkins2, Kathy Ridgway2

Methodology

To increase potato attribute, methionine was used to generate methional. To add a

malt attribute, isoleucine was used to generate 2-methylbutanal.

The two FPs and controls (blank and reducing sugar only) were added to the 3

systems: liver, water and a free amino acid reducing sugar model, based on

raw liver analysis.

Analysis of the sample by: (i) human sensory; (ii) targeted analysis (amino acids

and odorants); (iii) non-targeted analysis using GC-qMS, and GC-Q/ToFMS.

.

Odorant OAV

Dimethyldisulfide 1

Hexanal 1

2-Acetyl-2-thiazoline 8

2-Acetylthiazole 3

Dimethylsulfide 226

Furaneol™ 407

Methional 778

Butanoic acid 5

Acetic acid 6

00.5

11.5

22.5

3Cooked potato

Cracker/popcorn

Fatty

Malt vinegarRoast Meat

Sour milk

Sweetcorn

OAV<1 Recombinant Original material

Summary

• Matrix has a great effect on the formation of odour attributes, odorants andvolatiles when applying flavour precursors.

• The free amino acid reducing sugar model, for understanding odour formation in

real systems, is slightly better than simple water system, but is not great.

• Consumption of isoleucine in each matrix relates to 2-methylbutanal formation,which leads to increased malt attribute. This is not the case for methionine.

• For methionine addition to liver, the observed greater consumption ofmethionine, leads to a larger number of VOCs present (as shown by non-targeted volatile analysis), not a greater increase in methional and potatoattribute (as shown by targeted analysis of odorants and amino acids, and

human sensory analysis).

Results Targeted Analysis (continued)

Fig 4a and 4b. Consumption of amino acid. Matrix has a significant effect onthe consumption of amino acids through processing. Consumption ofisoleucine relates to 2-methylbutanal formation, which leads to an increase in maltattribute. This is not the case for methionine. n = 4, mean and 95% C. I., letters areTukey groups (p<0.05).

• Why is there a greater consumption of methionine in liver samples?

• What additional compounds are formed from methionine?

Results 2 Non-targeted Analysis

Fig 5a & 5b. PCA on all data (molecular features). Groups are based on matrix.

For GC-qMS (5a) there are separate groupings for liver samples and liversamples with added methionine. For GC-Q/ToFMS (5b) there are separate

groupings for water samples and water samples with added methionine.

Key: liver , model , water , blank , control , isoleucine , methionine .

• What causes liver sample groupings?

• Liver with methionine samples have more molecular features!

Fig 7. Tentatively identified compounds that are unique to the liver sample withadded methionine. A hypothesis is that methionine reacts with chemicalcompounds present only in the liver matrix. Key: Identified by GC-qMS and GC-Q/ToFMS blue, identified by GC-Q/ToFMS only black.

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Fig. 2b Malt Attribute from Isoleucine

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Fig 3b. 2-Methylbutanal from Isoleucine

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Water Model Liver Water Model Liver Water Model Liver Water Model Liver Water Model Liver

Methional Methanethiol Dimethyldisulfide Dimethyltrisulfide Dimethylsulfide

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Fig 3a. Odorants from Methionine

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Fig 4b. Consumption f Isoleucine

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Fig 4a. Consumption of Methionine

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Fig 3a and 3b. Formation of keyodorants relates to odour attributeformation. Matrix has a significanteffect on odorant formation.Isoleucine increases 2-methylbutanal inwater > model > liver. Methionineincreases targeted odorants in water >model > liver.n = 8, mean and 95% C.I., letters areTukey groups for each odorant(p<0.05).

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Fig 6. PCA of GC-Q/ToMS data (liversamples only) shows groups basedon amino acid. There are separategroupings for liver samples and liver

samples with added methionine.Key: blank , control , isoleucine ,

methionine .

A

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PC 2

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Fig. 5a Fig. 5b

PC 3

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Recombinant Liver n=12