PROCESS FOR HEAT-TREATING ONIONS

Abstract

The present invention relates to a process for the production of heat-treated onions composition. In particularly the invention relates to a process for the production of heat-treated onions composition under vacuum between 100 to 750 mbar and wherein the moisture content of the heat-treated onions composition is below 80 wt % (based on total composition).

Claims

1. A process for the production of heat-treated onions composition comprising the steps of a) peeling and dicing onion; b) mixing the peeled and diced onion with oil; c) heating the mix from step b) between a temperature range of 55-99? C. for 15 to 240 min reducing moisture content of the mix; d) cooling wherein the heating of the mix is done under vacuum between 100 to 750 mbar and wherein the moisture content of the heat-treated onions composition after step d) is below 80 wt % (based on total composition).

2. A process for the production of heat-treated onions composition as claimed in claim 1, wherein in step b) 80 to 95 wt % (by weight of the total composition) of the peeled and diced onion are mixed with 5 to 20 wt % (by weight of the total composition) of oil.

3. A process for the production of heat-treated onions composition as claimed in claim 1, wherein the heating is done via double jacketed steam.

4. A process for the production of heat-treated onions composition as claimed in claim 1, wherein the heating is done at a temperature range of 55 to 95? C. for 20 to 120 min.

5. A process for the production of heat-treated onions composition as claimed in claim 1, wherein the vacuum is between 180 to 710 mbar.

6. A process for the production of a heat-treated onions composition as claimed in claim 1, wherein the oil is sunflower oil.

7. A process for the production of a heat-treated onions composition as claimed in claim 1, wherein the sunflower oil comprises the fatty acids C16:0 in the range of 1 to 25 wt % (based on weight of total fat) and C18:1 in the range of 60 to 90 wt % (based on weight of total fat) and C18:2 in the range of 0.1 to 20 wt % (based on weight of total fat).

8. A process for the production of a heat-treated onions composition as claimed in claim 1, wherein heat-treated onions composition does not comprise starch and/or flour.

9. A process for the production of a heat-treated onions composition as claimed in claim 1, wherein the moisture content of the heat-treated onions composition after step d) is between 7 to 75 wt % (based on total composition).

10. A heat-treated onion composition comprising a combination of 5 to 100 mg/kg of cis/trans-methyl-1-propenyl disulphide and cis/trans-methyl-1-propenyl trisulphide and (cis,cis)/(cis,trans)/(trans,trans)-di-1-propenyl trisulphide (by total weight of the composition).

11. A heat-treated onion composition as claimed in claim 10 comprising at least 3.0 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and at least 1.3 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and at least 0.2 mg/kg (cis,cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition).

12. A heat-treated onion composition as claimed in claim 10, wherein the composition comprising at least 10.0 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and at least 2.5 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and at least 0.4 mg/kg (cis,cis)/(cis,trans)/(trans,trans)-di-1-propenyl trisulphide (by total weight of the composition).

13. A heat-treated onion composition as claimed in claim 10, wherein the composition comprising between 10.0 to 65 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and between 2.5 to 20 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and between 0.4 to 2.5 mg/kg (cis,cis)/(cis,trans)/(trans,trans)-di-1-propenyl trisulphide (by total weight of the composition).

14. (canceled)

Description

DETAILED DESCRIPTION OF THE INVENTION

[0012] In a preferred aspect the present invention pertains to a process for the production of heat-treated onions composition comprising the steps of: [0013] a) peeling and dicing onions; [0014] b) mixing the peeled and diced onion with oil; [0015] c) heating the mix from step b) between a temperature range of 55-99? C. for 15 to 240 min reducing moisture content of the mix; [0016] d) cooling;
wherein the heating of the mix is done under vacuum between 100 to 750 mbar and wherein the moisture content of the heat-treated onions composition after step d) is below 80 wt % (based on total composition).

[0017] In a preferred aspect the present invention pertains to a process for the production of heat-treated onions composition comprising the steps of: [0018] a) peeling and dicing onions; [0019] b) mixing 80 to 95 wt % (by weight of the total composition) of the peeled and diced onion with 5 to 20 wt % (by weight of the total composition) of oil; [0020] c) heating the mix from step b) between a temperature range of 55-99? C. for 15 to 240 min reducing moisture content of the mix; [0021] d) cooling;
wherein the heating of the mix is done under vacuum between 100 to 750 mbar and wherein the moisture content of the heat-treated onions composition after step d) is below 80 wt % (based on total composition).

[0022] In a preferred aspect the present invention pertains to a process for the production of heat-treated onions composition comprising the steps of: [0023] a) peeling and dicing onions; [0024] b) mixing 85 to 93 wt % (by weight of the total composition) of the peeled and diced onion with 7 to 15 wt % (by weight of the total composition) of oil; [0025] c) heating the mix from step b) between a temperature range of 55-99? C. for 15 to 240 min reducing moisture content of the mix; [0026] d) cooling;
wherein the heating of the mix is done under vacuum between 100 to 750 mbar and wherein the moisture content of the heat-treated onions composition after step d) is below 80 wt % (based on total composition).

[0027] In a preferred aspect the present invention pertains to a process for the production of heat-treated onions composition comprising the steps of: [0028] a) peeling and dicing onions; [0029] b) mixing 85 to 93 wt % (by weight of the total composition) of the peeled and diced onion with 7 to 15 wt % (by weight of the total composition) of oil; [0030] c) heating the mix from step b) between a temperature range of 60-95? C. for 15 to 240 min reducing moisture content of the mix; [0031] d) cooling;
wherein the heating of the mix is done under vacuum between 100 to 750 mbar and wherein the moisture content of the heat-treated onions composition after step d) is below 80 wt % (based on total composition).

[0032] In a preferred aspect the present invention pertains to a process for the production of heat-treated onions composition comprising the steps of: [0033] a) peeling and dicing onions; [0034] b) mixing 85 to 93 wt % (by weight of the total composition) of the peeled and diced onion with 7 to 15 wt % (by weight of the total composition) of oil; [0035] c) heating the mix from step b) between a temperature range of 55-99? C. for 15 to 240 min reducing moisture content of the mix; [0036] d) cooling;
wherein the heating of the mix is done under vacuum between 100 to 750 mbar and wherein the moisture content of the heat-treated onions composition after step d) is below 80 wt % (based on total composition) and wherein the oil comprises the fatty acids C16:0 in the range of 1 to 25 wt % (based on weight of total fat) and C18:1 in the range of 60 to 90 wt % (based on weight of total fat) and C18:2 in the range of 0.1 to 20 wt % (based on weight of total fat).

[0037] In a second aspect the invention relates to a heat-treated onion composition comprising a combination of 5 to 100 mg/kg of cis/trans-methyl-1-propenyl disulphide and cis/trans-methyl-1-propenyl trisulphide and (cis,cis)/(cis,trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition), preferably between 7 to 80 mg/kg of the combination consisting of cis/trans-methyl-1-propenyl disulphide and cis/trans-methyl-1-propenyl trisulphide and (cis,cis)/(cis,trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition).

[0038] In a preferred aspect the invention relates to a heat-treated onion composition comprising at least 3.0 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and at least 1.3 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and at least 0.2 mg/kg (cis, cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition).

[0039] In a preferred aspect the invention relates to a heat-treated onion composition comprising between 10.0 to 65 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and between 2.5 to 20 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and between 0.4 to 2.5 mg/kg (cis, cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition).

[0040] In a preferred aspect of the invention, there is provided a product obtainable by the process of the invention. All combinations should be considered.

[0041] The term onion as used herein, unless indicated otherwise, refers to onion bulb. It refers to a non-dehydrated onion. In an embodiment the heat-treated onions composition comprises between 75 to 99 wt % of peeled and sliced onions (by weight of the total composition), preferable between 80 to 99 wt %, preferable between 80 to 96 wt %, preferable between 85 to 99 wt %, preferable between 85 to 96 wt %, preferable between 85 to 93 wt % (by weight of the total composition).

[0042] The term oil of the present invention has a solid fat content (SFC) at 20? C. below 12 wt %, preferably has a solid fat content (SFC) at 20? C. between 0 to 12 wt %, preferably has a solid fat content (SFC) at 20? C. between 0 to 10 wt %, preferably has a solid fat content (SFC) at 20? C. between 0 to 8 wt %, preferably has a solid fat content (SFC) at 20? C. between 0 to 6 wt %. The oil or fat of the present invention has a solid fat content (SFC) at 20? C. below 6 wt %. Oil is liquid at a temperature of 25? C., preferably at a room temperature of 20? C. Sunflower oil has a solid fat content (SFC) at 20? ? C. of 0. Olive oil has a solid fat content (SFC) at 20? C. of 0. In a preferred embodiment the oil is selected from the group consisting of sunflower oil, rapeseed oil, cotton seed oil, peanut oil, soy oil, olive oil, algal oil, safflower oil, corn oil, rice bran oil, sesame oil, hazelnut oil, avocado oil, almond oil, walnut oil or a combination thereof; more preferably sunflower oil or rapeseed oil or a combination thereof; most preferably sunflower oil. The term sunflower oil comprises standard sunflower oil or high-oleic sunflower oil or a combination thereof. In a further embodiment, the heat-treated onion comprises oil in an amount between 5 to 20% (by weight of the total composition), preferably between 6 to 18%, preferably between 7 to 17%, preferably between 7 to 15%, preferably 8 to 15%, preferably 8 to 13% (by weight of the total composition).

[0043] In a further embodiment the term oil according to this invention comprises the fatty acids C16:0 in the range of 1 to 25 wt % (based on weight of total fat) and C18:1 in the range of 60 to 90 wt % (based on weight of total fat) and C18:2 in the range of 0.1 to 20 wt % (based on weight of total fat) is a high oleic sunflower oil. In an embodiment the oil comprises C16:0. C16:0 is palmitic acid. In a further embodiment C16:0 is in the range of 1 to 25 wt % (based on weight of total fat), preferably C16:0 is in the range of 1 to 20 wt % (based on weight of total fat), preferably C16:0 is in the range of 1 to 15 wt % (based on weight of total fat), preferably C16:0 is in the range of 1 to 10 wt % (based on weight of total fat), more preferably C16:0 is in the range of 2 to 7 wt % (based on weight of total fat). In an embodiment the oil comprises C18:1. C18:1 is oleic acid. In a further embodiment C18:1 is in the range of 60 to 90 wt % (based on weight of total fat), preferably C18:1 is in the range of 65 to 90 wt % (based on weight of total fat), preferably C18:1 is in the range of 70 to 90 wt % (based on weight of total fat), preferably C18:1 is in the range of 75 to 90 wt % (based on weight of total fat), more preferably C18:1 is in the range of 80 to 90 wt % (based on weight of total fat). In an embodiment the oil comprises C18:2. C18:2 is linoleic acid. In a further embodiment C18:2 is in the range of 0.1 to 20 wt % (based on weight of total fat), preferably C18:1 is in the range of 0.1 to 15 wt % (based on weight of total fat), preferably C18:1 is in the range of 0.1 to 10 wt % (based on weight of total fat), preferably C18:1 is in the range of 0.5 to 10 wt % (based on weight of total fat), more preferably C18:1 is in the range of 0.5 to 5 wt % (based on weight of total fat). In an embodiment the oil of this invention has a melting point of ?1 to +5? C. and relative density of 0.91. It is preferred that the oil is liquid at room temperature (20? C.) to avoid unnecessary heating during storage and transfer of oil into the process, higher storage temperature of oil would already lead to oxidation of oil.

[0044] Heat-treating is a process wherein moisture from onion is removed to a desired level and raw taste is eliminated and characteristic fried onion flavor is generated in the end product. The heat-treatment with oil is done between a temperature range of 55-99? C. for 15 to 240 min, preferably between a temperature range of 55 to 95? C. for 15 to 240 min, preferably between a temperature range of 60 to 95? C. for 15 to 240 min, 55-99? C. for 20 to 180 min, preferably between a temperature range of 55 to 95? C. for 20 to 120 min, preferably between a temperature range of 60 to 95? C. for 25 to 100 min, preferably a temperature range of 60 to 95? C. for 25 to 100 min between 30 to 80 min. The heating of the mix is done under vacuum between 100 to 750 mbar, preferably between 180 to 710 mbar, preferably between 100 to 500 mbar, preferably between 100 to 300 mbar.

[0045] Cooling means that the temperature of the heat-treated onion is reduced. It is desirable to have the heat-treated onion at temperature between 20 to 30? C., more preferably between 20 to 25? C.

[0046] In an embodiment the moisture content of the heat-treated onions composition after step d) is below 80 wt % (based on total composition), preferably below 75 wt %, preferably below 72 wt %, preferably below 70 wt %, preferably below 60 wt %, preferably below 50 wt %, preferably between 7 to 80 wt %, preferably between 7 to 75 wt %, preferably between 7 to 72 wt %, preferably between 7 to 70 wt %, preferably between 7 to 60 wt %, preferably between 7 to 50 wt % (based on total composition).

[0047] In an embodiment the process for the production of heat-treated onions composition does not comprise starch and/or flour. In an embodiment the process for the production of heat-treated onions composition is free from starch and/or flour.

[0048] In a second aspect the present invention pertains to a heat-treated onion composition comprising a combination of 5 to 100 mg/kg of cis/trans-methyl-1-propenyl disulphide and cis/trans-methyl-1-propenyl trisulphide and (cis,cis)/(cis, trans)/(trans,trans)-di-1-propenyl trisulphide (by total weight of the composition), preferably between 7 to 100 mg/kg of the combination consisting of cis/trans-methyl-1-propenyl disulphide and cis/trans-methyl-1-propenyl trisulphide and (cis,cis)/(cis,trans)/(trans,trans)-di-1-propenyl trisulphide (by total weight of the composition), preferably between 10 to 100 mg/kg of the combination consisting of cis/trans-methyl-1-propenyl disulphide and cis/trans-methyl-1-propenyl trisulphide and (cis, cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition), preferably between 10 to 80 mg/kg of the combination consisting of cis/trans-methyl-1-propenyl disulphide and cis/trans-methyl-1-propenyl trisulphide and (cis, cis)/(cis, trans)/(trans,trans)-di-1-propenyl trisulphide (by total weight of the composition).

[0049] In a preferred aspect the invention relates to a heat-treated onion composition comprising at least 3.0 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and at least 1.3 mg/kg cis/trans-methyl-1-propenyl trisulphide (cis, cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition) and at least 0.2 mg/kg (cis,cis)/(cis, trans)/(trans,trans)-di-1-propenyl trisulphide (by total weight of the composition), preferably at least 6.5 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and at least 2.0 mg/kg (cis,cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition) and at least 0.4 mg/kg (cis,cis)/(cis, trans)/(trans,trans)-di-1-propenyl trisulphide (by total weight of the composition), preferably at least 10.0 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and at least 2.5 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and at least 0.5 mg/kg (cis, cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition).

[0050] In a preferred aspect the invention relates to a heat-treated onion composition comprising between 3.0 to 100 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and between 2.5 to 20 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and between 0.4 to 2.5 mg/kg (cis, cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition), preferably between 6.5 to 100 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and between 2.5 to 25 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and between 0.4 to 3.0 mg/kg (cis,cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition), preferably between 10.0 to 65 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and between 2.5 to 20 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and between 0.5 to 2.5 mg/kg (cis, cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition).

[0051] Those skilled in the art will understand that they can freely combine all features of the present invention disclosed herein. In particular, features described for different embodiments of the present invention may be combined. Where known equivalents exist to specific features, such equivalents are incorporated as if specifically referred to in this specification.

EXAMPLES

Example 1: Process

[0052] Onions are peeled and diced into size of 10?10 mm. This mix of diced fresh onions are fed into Stephan mixer (V-MC 401 STEPHAN Vacutherm) with oil.

[0053] When the onion and oil mix is in the vessel, the lid is closed and the pressure is decreased with a vacuum pump. The heating is applied via double jacketed steam.

[0054] Quantification of volatile sulfide compounds was achieved via headspace solid-phase microextraction combined with gas chromatography-triple quadrupole-mass spectrometry (HS-SPME-GC-MS/MS). Approximately 1 g of homogenized onion sample was weighed in a glass vial and 5 mL of 20% aqueous sodium chloride solution was added before closing the vial. For analysis the samples were incubated for 10 min at 65? C. and then the SPME fiber (2 cm; 50/30 mm DVB/CAR on PDMS, Supelco) was exposed to the headspace above the sample for 30 min at the same temperature while shaking for both steps. Afterwards the fiber was placed into the injector at 220? C. for desorption. The used column for GC was a DB 5MS UI (30 m?0.25 mm?0.25 ?m, Agilent) with the temperature program starting at 40? C. (3 min hold) and a heat ramp to 300? C. at 15? C./min (5 min hold) with a helium carrier gas flow of 1.5 mL/min. The MS/MS detection was run in Multiple-reaction monitoring (MRM) mode using electron ionization (EI) at 70 eV ionization energy with source temperature at 230? C. and quadrupole temperatures at 150? C. The transfer line from GC to the detector was kept at 250? C. Two MRM transitions were used for each analyte. One was applied for quantification (Quantifier) and the other one to confirm the identity of the specific compound (Qualifier) by comparing Quantifier/Qualifier area ratios to beforehand determined values. Quantification was done using the internal standard (IS) method with diallyl disulfide as the IS

Examples 2-5

[0055] Comparison example 2 is done according to example 1, but without closing the lid and applying a vacuum (open vessel). Comp. example 3 and examples 4-5 are prepared corresponding to example 1.

TABLE-US-00001 Comp. Comp. Ex 2 Ex 3 Ex 4 Ex. 5 Amount of Onion 90% 90% 90% 90% Type of oil sunflower sunflower sunflower HOSO oil oil oil Amount of oil 10% 10% 10% 10% Pressure [mbar] atmo- 800 700 700 spheric Temperature of 100 85 75 75 onion-oil-mix [? C.] Time [min] 50 40 35 35 cis/trans-methyl-1- 0.311 1.202 3.473 3.601 propenyl disulphide [mg/kg] cis/trans-methyl-1- 0.019 1.077 1.599 1.730 propenyl trisulphide [mg/kg] (cis, cis)/(cis, 0.0004 0.183 0.307 0.397 trans)/(trans, trans)- di-1-propenyl trisulphide [mg/kg] Moisture content 70 70 70 70 Sensory data Saut?ed Translucent Saut?ed Saut?ed onions onions onions onions cooked boiled Clear Clear taste, local onion difference difference browning taste, vs comp. vs comp. slight ex. 1. More ex. 1. browning overall More intense, overall more fried intense, onion and more fried sweet onion note, soft note, soft texture, texture, lighter lighter homo- color genous color *Sensory data More than 2 More than 2 Less than Less than Off note eval- on scale of on scale of 5 2 on 1 on uation by panel 5 (probably (probably scale of 5 scale of 5 after 9 months due to lipid due to lipid oxidation oxidation compounds) compounds) *0No off note, 5Very high off notes (Flavor and Aroma); 20 panellists tested.

[0056] It is shown that by using a process of the invention for heat-treating onions by applying a vacuum below 800 mbar, certain aroma compounds are increased resulting in a better fried onion note. Comp. Ex. 3 corresponds JP2004267128 disclosing an onion heat-treatment using a vacuum of 800 mbar. The heat-treating onions composition of examples 4 and 5 comprising at least 3.0 mg/kg cis/trans-methyl-1-propenyl disulphide (by total weight of the composition) and at least 1.3 mg/kg cis/trans-methyl-1-propenyl trisulphide (by total weight of the composition) and at least 0.2 mg/kg (cis,cis)/(cis, trans)/(trans, trans)-di-1-propenyl trisulphide (by total weight of the composition), which result in the better fried onion taste compared to comparison examples 2 and 3. Using HOSO (high-oleic sunflower oil) result in a better shelf-life taste of the product.

Examples 6 to 8

[0057] The following examples are prepared corresponding to example 1.

TABLE-US-00002 Ex 6 Ex 7 Ex 8 Amount of Onion 90% 90% 85% Type of oil sunflower sunflower sunflower oil oil oil Amount of oil 10% 10% 15% Pressure [mbar] 200 200 200 Temperature of onion-oil-mix 80 85 85 [? C.] Time [min] 75 83 83 cis/trans-methyl-1-propenyl 13.220 51.699 48.876 disulphide [mg/kg] cis/trans-methyl-1-propenyl 3.372 13.569 14.467 trisulphide [mg/kg] (cis,cis)/(cis, trans)/(trans,trans)- 0.756 1.769 1.931 di-1-propenyl trisulphide [mg/kg] Moisture content 45 15 12 Sensory data caramelized roasted roasted onions onions onions sweet, smokey, smokey, caramelized roasted little more onion, fried onion, roasted onion, soft harder onion taste texture, texture, compared caramel darker to ex 6, color color harder texture, darker color, oily

[0058] It is shown that for caramelized or roasted onions the flavor compounds are further increased for heat-treated onions composition under vacuum.

Example 9

[0059] An onion soup has been prepared using 500 g of caramelized onions according to example 6 and 11 bouillon broth (soup A). In addition, a second onion soup has been prepared by using 500 g of onions according to example 1 and 11 bouillon broth (soup B). Both onion soups have been cooked for 5 min.

[0060] 6 internal experienced panelists were used to rate the taste of soup A and soup B. All 6 panelists rated soup A as being much more intense compared to soup B.

Example 10

[0061] A Bolognese sauce has been prepared by frying 1 kg minced meat (beef) adding salt and black pepper and 1.5l tomato sauce. The obtained non-final sauce has been divided in two equal portions. To one portion 300 gr of a 50/50 mix of onions according to example 6 and example 7 are added and further cooked for 10 min (Bolognese A). To the other portion 300 gr of onions according to example 1 are added and also cooked for 10 min (Bolognese B). 6 internal experienced panelists were used to rate the taste of Bolognese A and Bolognese B. All 6 panelists rated Bolognese A as having a more round and sweeter taste, which was more appreciated compared to Bolognese B.

Comp. Example 11: Sous Vide Cooking

[0062] Onions are peeled and diced into size of 10?10 mm. This mix of diced fresh onions are fed into a plastic bag with oil and vacuum sealed.

TABLE-US-00003 Comp. Ex 11 Sous vide Amount of Onion 90% Type of oil sunflower oil Amount of oil 10% Temperature of onion-oil-mix [? C.] 100 Time [min] 1440 cis/trans-methyl-1-propenyl disulphide [mg/kg] 2.004 cis/trans-methyl-1-propenyl trisulphide [mg/kg] 1.103 (cis, cis)/(cis, trans)/(trans, trans)-di-1- 0.101 propenyl trisulphide [mg/kg] Moisture content [wt %] 84 Sensory data Brown onions with slight caramel note and boiled onion aroma, animalic

[0063] It is shown that by using sous vide technology to cook onions, certain aroma compounds are not as much increased and not resulting in a better fried onion note compared using a process of the invention. In addition, the final moisture content of the sous vide product is 84 wt % as the water can't be evaporated due to the sealed plastic bag.