Field of the invention

The present invention relates to retorted, ready to use, food compositions including meat, fish or their derivatives, and their methods of production.

Background of the invention

Ready to use food compositions are known and available in a range of formats, such as stocks, gravies, broths, bouillons, consommes and sauces. There is particular consumer demand for ready to use food compositions that include meat, fish or their derivatives. Although ready to use food compositions can vary in their fat content, there is consumer demand for food compositions with a fat content of less than 5% by weight. Ready to use food compositions have increased consumer convenience, as they merely require heating prior to consumption. This is in contrast to concentrated food products, which require dilution before use. As such, all ready to use food compositions generally have a higher water content than concentrated food products. As a result of this high water content, such food compositions are not inherently stable to microbiological spoilage. Ready to use stocks, gravies, broths, bouillons and consommes have a particularly high water content, typically at least 80% by weight. This is higher than that of products such as ready to use sauces, which can have a water content as low as 30% by weight.

Microbiological spoilage may be alleviated by providing the ready to use food composition as a chilled or frozen product. However, chilled products lack convenience due to their short shelf life and the need to keep them chilled. Similarly, frozen products are also less convenient due to the need to thaw them before heating prior to consumption. Ambient ready to use food compositions, i.e. food compositions that may be stably stored at ambient temperatures, are therefore more convenient for the consumer, but require sterilisation by heat treatment to kill any microorganisms present, such as the anaerobic organism Clostridium Botulinum.

This sterilisation may be achieved by ultra-high-temperature (UHT) processing, whereby the food composition is heated at above 135 °C for a short period of time, typically less than 30 seconds or even less than 10 seconds. Alternatively, sterilisation may be achieved by a retorting process, whereby the food composition is sealed within a retortable package, and heated at ~\ 00°C - 130°C for at least 2 minutes at a pressure of at least 100 kPa above atmospheric pressure. However, retorted meat or fish based compositions with a particularly high water content, such as stocks, gravies, broths, bouillons and consommes, have poor taste and aroma. This bitter processed taste and aroma is detectable after the retorted ready to use product is heated by the consumer prior to consumption. Although this undesirable bitter taste may in some contexts be masked using other flavours, this can lead to a product where the resulting overall flavour is not that typically expected by consumers. Although rapidly processed UHT products do not experience the same bitter taste problem, the use of UHT involves a certain manufacturing capability that some food manufacturers will not possess. For example, UHT processing requires specialist sterilised equipment.

Certain methods of suppressing unwanted flavours and aromas are known. For example, EP1600496 and EP0983727 disclose the use of trehalose based compounds to suppress unwanted flavours and aromas in a range of products across food, cosmetic and drug industries. However, these documents do not address the specific problem that arises from the use of a retorting process to sterilise food. Further, these documents are not concerned with ready to use meat or fish containing food compositions with a particularly high water content of at least 80%.

Summary of the invention

It has been found that, when at least one polyol compound as defined herein is included in a meat or fish containing food composition prior to retorting, the unwanted bitter taste and aroma is suppressed in the final retorted product. The final retorted product is also an ambient ready to use food composition and so has increased consumer convenience, and is stable to microbiological spoilage.

In a first aspect, the present invention provides a retortable food composition comprising meat, fish, or derivatives thereof; at least 80 wt% water; less than 5 wt% fat; and at least one polyol of the following structure:

wherein L is either a direct bond or CH ₂ ; R ¹ and R ² are each independently selected from H, or a C C ₆ alkyl group, wherein the C C ₆ alkyl group is optionally substituted with one or more substituents; and wherein the food composition is sealed within a retortable package.

When the retortable food composition according to the first aspect of the invention is retorted, the resulting retorted food composition has improved flavour and reduced unwanted bitterness. Without wishing to be bound by theory, it is thought that the sterilisation of meat or fish containing food compositions by retorting causes breakdown of food compounds to form volatile compounds, such as aldehyde compounds, which cause unpleasant organoleptic properties when the product is eventually heated by the consumer. The polyol compounds disclosed herein, when included in the food composition prior to retorting, act as a suppressant to the unwanted volatile compounds, improving the taste and also smell of the food composition once it has been retorted. This suppression of bitter flavours is not observed if the polyol compounds disclosed herein are added to the food composition after the retorting process is complete. Without wishing to be bound by theory, it is thought that two -OH groups along the open chain fragment of the polyol compounds disclosed herein react with the aldehyde group of the volatile compounds produced during retortion, thereby reducing or eliminating the concentration of these volatile compounds in the final retorted ready to use food composition. As such, the suppression of unwanted bitterness is achieved in the final retorted product whilst maintaining the typical flavour expected by the consumer of the ready to use product in question. This is in contrast to methods where the volatile compounds remain present in the final product, and the bitterness resulting from such compounds is merely masked by addition of other flavourings (such as alcohol, for example) thereby having an adverse effect on the final overall flavour of the product.

The present invention has specific applicability for retorted ready to use food products with at least 80% water and less than 5% fat, such as stocks, gravies, broths, bouillons, consommes. The bitter processed taste in prior art food compositions with at least 80% water and less than 5% fat is particularly prevalent. It is thought that this is due to the lighter and more delicate flavour of these comparatively low fat content, particularly high water content products, allowing the bitter taste to be readily detectible by the consumer. This is in contrast to ready to use food compositions such as sauces, which have a lower water content as low as 30%, and therefore a stronger flavour, such that any bitter taste is not detectable by the consumer. Similarly, a fat content of more than 5% typically masks the unwanted bitterness, such that any bitter taste is not detectable by the consumer. The present invention also has specific applicability for meat and fish containing compositions, as the unwanted bitter taste is not observed in retorted ready to use compositions that do not include meat, fish or their derivatives.

In a second aspect, the present invention provides a process of retorting a food composition comprising the steps of:

providing the retortable food composition as defined in the first aspect of the invention, and

heating the retortable food composition at a temperature of 100-130 ^e C for at least 2 minutes at a pressure of at least 100 kPa above atmospheric pressure.

In a third aspect the present invention provides a retorted food composition obtained by the process according to the second aspect of the invention.

In a fourth aspect the present invention provides the use of at least one polyol compound as defined herein to suppress bitterness in a food composition, said food composition comprising meat, fish, or derivatives thereof, at least 80 wt% water, and less than 5 wt% fat.

Description of the preferred embodiments

As used herein, the term "ready to use" in relation to a food composition refers to a food composition that does not require dilution prior to consumption.

As used herein, the term "retortable food composition" refers to a food composition that is capable of being subjected to a retorting process. Meanwhile, the term "retorted food composition" refers to a food composition that has already been subjected to a retorting process.

A retortable food composition is typically rendered capable of being subjected to a retorting process by being sealed within a retortable package. As used herein, the term "retortable package" refers to a package that is able to withstand the temperature and pressure of a retorting process, and capable of forming an airtight seal around the food composition. Retortable packages are well-known and the skilled person will be familiar with their construction. As will be appreciated by the skilled person, the precise construction of a retortable package will vary depending on the specifics of the food product in question, but all retortable packages are of a construction capable of withstanding a retorting process. The retortable package may take the form of a pouch, a can, a pot, a tray, a bottle, a jar, a tub or a tottle. Preferably, the retortable package is a pouch or a can. More preferably, the retortable package is a pouch.

A pouch is typically a flexible package, which therefore offers a greater array of storage options and good consumer convenience. The pouch preferably comprises at least one plastic material. In particular, the at least one plastic material is polyester, polyethylene, polypropylene, nylon or combinations thereof. The pouch may also comprise at least one metal material, wherein the metal material is preferably aluminium.

The retortable pouch may also be a laminate pouch. The term "laminate pouch" refers to a pouch constructed from multiple layers. A retortable laminate pouch is typically constructed from a series of metal and plastic layers. The plastic layers of the laminate typically include polyester, polyethylene, polypropylene, and nylon. The metal layers of the laminate typically include aluminium.

Any suitable retorting process conditions may be used in the context of the present invention. The skilled person will be aware that retorting is a food processing method used for a pouch, can, pot, tray, bottle, jar, tub or tottle, where the food composition is first sealed within the retortable package, and then heated at high temperature and pressure to sterilize the food composition. In practice, suitable temperature and pressure conditions are used to retort the food composition such that the degree of sterilisation complies with generally acknowledged commercial food safety requirements. Typically, the retortable food composition is heated at a temperature of 100-130 ^e C for at least 2 minutes at a pressure of at least 100 kPa above atmospheric pressure, preferably at a pressure of 100-240 kPa above atmospheric pressure. Preferably, the food composition is heated for a time period of at least 6 minutes. More preferably, the food composition is heated for a time period of 10-30 minutes. The resulting product preferably has an ambient shelf life of at least a year, which means that it may be stably stored at ambient temperature for at least a year. The packaged food composition is heated within a pressurized vessel known as a retort. Certain specifications, concerning both time and temperature are adhered to and repeated, batch after batch, to obtain a series of sterile products of uniform quality. Typically, the retorting process is achieved by using steam, raining, spray water or full water immersion with overpressure from compressed air. Microwave heating may also be used in a retorting process.

The retortable food compositions of the present invention, and the retorted food compositions of the present invention, include meat, or fish, or derivatives thereof. Meat or fish and their derivatives includes meat flesh or fish flesh, meat fats or fish fats (meat fats are sometimes referred to in the art as meat "dripping"), meat juices or fish juices, and meat bone extracts or fish bone extracts. As the skilled person will appreciate, the term "fish or derivatives thereof" does not include shellfish or derivatives of shellfish.

Preferably, the retortable food composition and the retorted food composition of the present invention includes meat or derivatives thereof. The term "meat" takes its usual definition in the art and refers to that of mammals or poultry. Preferably, the food compositions of the present invention comprise beef, chicken, lamb, pork, turkey, or derivatives thereof. It is especially preferred that the food compositions of the present invention comprise beef, chicken, or derivatives thereof, as particularly good suppression of bitterness is achieved in the context of such compositions. Furthermore, products which contain meat juices or bone extracts are also particularly improved by the invention.

The meat or fish component of the food composition may be added to the composition in the form of a chef made stock. Recipes for chef's stocks vary widely, but as an example 1 .5 kg of either meat or fish may be simmered with vegetables in three litres of water for twelve hours, then cooled, and filtered.

The retortable food composition and the retorted food composition of the present invention have a water content of at least 80 wt%. Preferably, the retortable food composition and/or the retorted food composition have a water content of at least 82 wt%, 84 wt% or 86 wt%. More preferably, the retortable food composition and/or the retorted food composition have a water content of at least 88 wt%, more preferably at least 90 wt%. As will be understood by the skilled person, the wt% refers to the % by weight based on the total weight of the food composition itself, i.e. the total weight of the food composition not including the weight of the retortable package. The retortable food composition and the retorted food composition of the present invention have a fat content of less than 5 wt%. The fat content refers to the total fat content of the food composition. The fat content therefore includes any fat present as a result of components such as the meat, fish, or derivatives thereof, and any fat added separately to the meat, fish, or derivatives thereof. The fat content is typically measured by the "international association for cereal science and technology" (ICC) standard method of acid hydrolysis. Preferably, the retortable food composition and/or the retorted food composition have a fat content of less than 4 wt%, more preferably less than 3 wt%. Most preferably, the retortable food composition and/or the retorted food composition have a fat content of less than 2 wt%, more preferably less than 1 .5 wt%. In some embodiments, the retortable food composition and/or the retorted food composition have a fat content of at least 0.01 wt%. In other embodiments, the retortable food composition and/or the retorted food composition have a fat content of 0 wt%. As will be understood by the skilled person, the wt% refers to the % by weight based on the total weight of the food composition itself, i.e. the total weight of the food composition not including the weight of the retortable package.

Preferably, the food composition of the present invention is a stock, gravy, broth, bouillon or consomme. Depending on the composition in question, colourings, flavourings, herbs, seasonings and thickeners such as starches may also be included as appropriate. For example, a gravy is distinguished from a stock by virtue of the presence of a thickener such as starch, preferably maize starch. The term "maize starch" includes both unmodified maize starch and modified maize starch. Modified maize starch is maize starch which has been chemically modified (e.g. modified by enzymatic treatment) or physically modified (e.g. modified by heat treatment). A stock is distinguished from a broth as a stock includes meat bone extracts or fish bone extracts, whilst a broth includes meat flesh extracts or fish flesh extracts. A bouillon is of a similar composition to a stock, but with a greater concentration of flavourings. Meanwhile, a consomme food composition is such that it appears to be clear, rather than opaque, to the consumer.

Preferably, the food composition is such that the principal flavour detected by the consumer is that arising from the meat, fish, or derivatives thereof. Examples of such compositions include a stock, gravy, broth or bouillon. The principal flavour of such compositions is in contrast to that of food compositions such as sauces, where meat, fish, or derivatives thereof may be present, but do not necessarily contribute to the principal flavour detected by the consumer.

Preferably, the food composition is free from cream, milk, and whey. The terms cream, milk, and whey, each take their usual definition in the art.

More preferably, the food composition of the present invention is a gravy or a stock.

The retortable food compositions of the present invention include at least one polyol of the following structure:

As used herein, the term "alkyl" refers to a straight or branched saturated or unsaturated alkyl group. Preferably, the alkyl group is a saturated alkyl group. More preferably, the alkyl group is a straight alkyl group. As used herein, the term "(C _a - C _b )alkyl" wherein a and b are integers refers to a straight or branched chain alkyl having from a to b carbon atoms. Thus, by way of example, a C C ₆ alkyl group refers to a group having from 1 to 6 carbon atoms, and so includes methyl, ethyl, n- propyl, isopropyl, n- butyl, isobutyl, sec-butyl, t-butyl, n-pentyl and n-hexyl.

As used herein, the term "optionally substituted" as applied to any moiety means that moiety is optionally substituted with at least one substituent. When the moiety is substituted with two or more substituents, said substituents may be the same or different.

The at least one polyol has L as either a direct bond or CH ₂ . Preferably, L is a direct bond.

R ¹ and R ² may be the same or different and are each independently selected from H, or a C C ₆ alkyl group, wherein the C C ₆ alkyl group is optionally substituted with one or more substituents. Preferably, R ¹ is a C C ₆ alkyl group, wherein the C C ₆ alkyl group is substituted by one or more optional substituents, and R ² is H. Preferably, the optionally substituted C C ₆ alkyl group is optionally substituted C C ₄ alkyl. More preferably, the optionally substituted C C ₆ alkyl group is an optionally substituted methyl or ethyl. Shorter alkyl chain lengths such as these are preferred as the resulting polyols give particularly effective suppression of bitter flavours. Without wishing to be bound by theory, it is thought that shorter alkyl chain lengths such as methyl or ethyl introduce reduced steric hindrance in comparison to larger alkyl chain lengths, and this reduction in steric hindrance results in more effective reaction with the unwanted bitter volatile compounds during the retorting process.

Preferably, the optional substituent is independently selected from -OH, - COOH, -O-glycosyl, -OC(0)CrC ₂ o alkyl, abietyl, dehydroabietyl, palustryl, pimaricyl, isopimaricyl, communicyl, or -OC C ₆ alkyl, wherein the C C ₆ alkyl group of the - OC C ₆ alkyl substituent is optionally substituted with one or more further substituents. The further optional substituents, when present on the C C ₆ alkyl group of the -OC C ₆ alkyl substituent, may be any of the optional substituents disclosed herein.

The term "-O-glycosyl" takes its usual definition in the art, and so refers to a cyclic monosaccharide group or oligosaccharide group bonded to the C C ₆ alkyl group via a glycosidic bond. Preferably, the O-glycosyl substituent, when present, is a monosaccharide group bonded to the C C ₆ alkyl group via a glycosidic bond.

The term "monosaccharide" takes its usual definition in the art and refers to a cyclic monosaccharide and can include glucose (also referred to in the art as dextrose), fructose (also referred to in the art as levulose) or galactose. Preferably, the monosaccharide is glucose. The term "oligosaccharide" takes its usual definition in the art and refers to a polymer including between two and ten polymerised cyclic monosaccharides, wherein each monosaccharide is bonded to its neighbouring monosaccharide(s) by a glycosidic bond. Preferably, the oligosaccharide group, when present, is a disaccharide or a trisaccharide. Preferably, the oligosaccharide comprises at least one glucose monosaccharide, more preferably the oligosaccharide group comprises only glucose monosaccharides.

The term "abietyl" refers to an abietic acid bonded to the C C ₆ alkyl group via an ester bond. Similarly, "dehydroabietyl", refers to dehydroabietic acid bonded to the C C ₆ alkyl group via an ester bond; "palustryl" refers to palustric acid bonded to the C C ₆ alkyl group via an ester bond; "pimaricyl" refers to pimaric acid bonded to the C C ₆ alkyl group via an ester bond; "isopimaricyl" refers to isopimaric acid bonded to the C C ₆ alkyl group via an ester bond; "communicyl" refers to communic acid bonded to the C C ₆ alkyl group via an ester bond. As will be appreciated by the skilled person, such substituents are present in the glycerol esters of wood rosin.

Preferably, the following substituents, when present, are located at the terminus of the C C ₆ alkyl chain: O-glycosyl, -OC(0)CrC ₂ o alkyl, abietyl, dehydroabietyl, palustryl, pimaricyl, isopimaricyl, communicyl, or -OC C ₆ alkyl, wherein the C C ₆ alkyl group of the -OC C ₆ alkyl substituent is optionally substituted with one or more further substituents. More preferably, there is at most one of these substituents present on the C C ₆ alkyi group. Having at most one of these substituents present and/or having the location of such substituents at the terminus of the C C ₆ alkyi chain reduces the amount of steric hindrance imparted on the polyol compounds.

The -OC(0)Ci-C ₂ o alkyi substituent, when present, is preferably -OC(O)Ci ₀ - C ₂ o alkyi, more preferably -OC(0)Ci ₅ -C ₂ o alkyi.

Preferably, the optional substituent is independently selected from -OH, - OC(0)Ci-C ₂ o alkyi, or -O-glycosyl, wherein the O-glycosyl is a monosaccharide group bonded to the C C ₆ alkyi group via a glycosidic bond.

In a particularly preferred embodiment, the C C ₆ alkyi group is substituted with one or more -OH groups. This results in particularly effective suppression of bitter flavours. Without wishing to be bound by theory, it is thought that substitution of the C C ₆ alkyi group with -OH groups provides additional reaction sites for the polyol compounds to react with the unwanted volatile compounds during retortion, resulting in particularly reduced concentration of unwanted volatile compounds in the retorted product. Preferably, the C C ₆ alkyi group is substituted with between one and five -OH groups.

The -OC C ₆ alkyi substituent, when present, is preferably -OC C ₃ alkyi. For example, the -OC C ₆ alkyi substituent, when present, is preferably -O-methyl, -O- ethyl, or -O-propyl.

The -OC C ₆ alkyi substituent, when present, is optionally substituted on its C C ₆ alkyi chain with one or more further substituents. These further optional substituents may be any of the optional substituents disclosed herein. Preferably, the optional substituent on the C C ₆ alkyi group of the -OC C ₆ alkyi substituent is independently selected from -OH, -OC(0)CrC ₂ o alkyi, or -OC C ₆ alkyi, more preferably -OH or -OC C ₆ alkyi.

When the -OC C ₆ alkyi substituent is substituted with a further -OC C ₆ alkyi, which is in turn itself substituted with a further -OC C ₆ alkyi, the resulting at least one polyol may take the form of a polymerised polyol structure, for example, polyglycerol.

In a particularly preferred embodiment, the at least one polyol is selected from the group consisting of glycerol, propylene glycol, glycerol monostearate, erythritol, xylitol, sorbitol, mannitol, isomalt, maltitol or combinations thereof. Even more preferably, the at least one polyol is selected from the group consisting of glycerol, glycerol monostearate, sorbitol, erythritol, isomalt, xylitol, maltitol. These polyol compounds are preferred as they contain an optimal combination of -OH sites capable of reacting with unwanted volatile compounds, and reduced steric hindrance. It is particularly preferred that the at least one polyol is glycerol. Glycerol produces particularly effective suppression of bitter flavours. Furthermore, glycerol is low cost, non-laxative and has good consumer acceptability and is therefore especially suitable in the context of food compositions.

In another preferred embodiment, the at least one polyol is selected from the group consisting of glycerol, propylene glycol, glycerol monostearate, xylitol, mannitol, isomalt, or combinations thereof.

The at least one polyol compounds defined herein have not previously been included in food compositions comprising meat, fish, or derivatives thereof; at least 80 wt% water and less than 5 wt% fat. The polyol compounds defined herein may generally function as a humectant, solvent or a sweetener, and these functions are either not needed, or are typically fulfilled by other ingredients, in the context of the specific food compositions disclosed herein. Specifically, there is no need for the ingredients to function as humectants or solvents in the context of the specific food compositions disclosed herein. Further, prior to the present invention, sweetness would typically be imparted on the specific food compositions disclosed herein by way of alternative sweeteners such as sucrose.

It should be emphasised that the at least one polyol must be present in the food composition prior to retorting. The at least one polyol can be added to the remaining ingredients of the retortable food composition at any point prior to the retorting process, but it is particularly preferred to incorporate it as the final addition just before the product is filled into pouches so that its effect during the retorting process is maximised.

Preferably, the at least one polyol is present in the retortable food composition in an amount of at least 0.1 wt%, preferably at least 0.25 wt%, as this gives effective reduction in bitter flavours. More preferably, the at least one polyol is present in the retortable food composition in an amount of at least 0.3 wt%, most preferably at least 0.5 wt%. When the polyol is present in an amount of at least 0.5 wt%, especially improved reduction in bitter flavours is achieved. In terms of the maximum amounts of polyol, the at least one polyol is preferably present within the retortable food composition in an amount of less than 3 wt%. Inclusion of the polyol above 3 wt% in the retortable food composition provides effective reduction in bitterness, but also results in residual sweetness in the final retorted product, which is less desirable to consumers in the context of the food compositions disclosed herein. More preferably, the at least one polyol is preferably present within the retortable food composition in an amount of less than 2 wt%, even more preferably less than 1 wt%. As will be understood by the skilled person, the wt% refers to the % by weight based on the total weight of the food composition itself, i.e. the total weight of the food composition not including the weight of the retortable package. The optimum amount of the at least one polyol within the retortable food composition depends on the specific food product in question.

As will be understood by the skilled person, the at least one polyol will be suitable for inclusion in a food composition and so will be edible and safe in the concentrations as indicated by the relevant authorities.

The present invention will now be demonstrated according to the following examples. All the numbers in the following tables are % by weight based on the weight of the total composition, not including the weight of the package.

Example 1 : Beef stock with glycerol added prior to retorting

A range of stocks were made using the recipes listed in the above table. Each stock composition was sealed in a retortable pouch, and then retorted. A panel of tasters reported a reduction in bitterness for the products where glycerol was included prior to retorting, in comparison to the products with no glycerol present prior to retorting. Where 0.25% and 0.5% glycerol was present prior to retorting, the bitterness was especially reduced. The panel also reported an improvement in the flavour with stronger beef and savoury notes at these levels. At 1 % and 2% glycerol, there was some initial sweetness, but this did not last long term, and the final aftertaste was that of pleasant beef notes. The stock samples were tasted at a temperature of at least 80 °C as this ensured detection of any undesirable volatiles present. Example 2: Beef stock with glycerol added after retorting

The stock with the same composition of example 1 , except with no added glycerol, was sealed in retortable pouch, then retorted, cooled and subsequently blended with 0.5% of glycerol. When the product was reheated to 80°C, a group of tasters found there was no elimination of bitter flavours. Specifically, there was a sour taste present, and a sweet taste that attempted to mask, rather than eliminate, the underlying bitterness.

By comparing the results of example 2 with example 1 , it can be seen that glycerol added to compositions prior to the retorting process (example 1 ) actively eliminates unwanted bitter flavours, whilst glycerol added post-retortion (example 2) simply masks, rather than eliminates, these bitter flavours.

Example 3: Beef gravy with glycerol added prior to retorting Water 91 .08 90.83 90.58 90.08

Modified maize

4.27 4.27 4.27 4.27

starch

Beef 0.8 0.8 0.8 0.8

Sugar 0.56 0.56 0.56 0.56

Salt 0.68 0.68 0.68 0.68

Flavourings 2.61 2.61 2.61 2.61

Glycerol 0.0 0.25 0.5 1 .0

A range of beef gravies were made using the recipes listed in the above table. Each gravy composition was sealed in a retortable pouch, then retorted. The compositions were then blind tasted by a trained sensory panel with eleven panellists. The panellists were served 59ml of sample, with 3 digit codes to make their assessment. Water and water biscuits were used as palate cleansers before and between each serving. All of the gravy samples were assessed at a temperature of at least 80 °C as this ensured detection of any undesirable volatiles present. Panellists were given 4 training sessions before entering scores individually. The aim of this training was to align all the panellists so that the maximum of difference between samples was recorded and to generate a vocabulary list with definitions to describe the sensory characteristics.

Panellists scored each attribute on an unstructured 0-100 line scale where 0 is no perception of the attribute, and 100 is the maximum possible perception of the attribute. As such, higher scores do not necessarily mean the product is better. Rather, it means the product displayed a higher level of the given attribute. For gravy, a lower bitter or "burnt" score, and a higher "roast" score, is preferable. The panellists used the "burnt" attributes, i.e. "burnt aroma, "burnt flavour", and "burnt aftertaste" to describe the unpleasant processed bitter flavour resulting from unwanted volatiles. The panellists performed 3 repetitions of the blind tastings. Averaged sensory scores from the panellists are given in the table below.

Added glycerol 0% 0.25% 0.5% 1 %

Roast aroma 1 3 7 5 Roast flavour 16 16 24 13

Thickness

(mouthfeel) 26 30 35 28

Burnt aroma 19 18 7 4

Burnt flavour 15 13 0 2

Burnt aftertaste 9 10 2 2

Sweet flavour 22 29 37 47

Sweet aftertaste 14 17 18 20

The compositions where glycerol was added prior to retorting had reduced "burnt" tastes i.e. reduced bitterness, in comparison to compositions with no glycerol added prior to retorting. Particularly reduced bitterness, and good levels of roast aroma, roast flavour and mouthfeel thickness were found at 0.5% added glycerol. At 1 % added glycerol, bitterness was still reduced, but there was some residual sweetness.

Example 4: Unretorted chicken stock with glycerol

A panel of six tasters assessed unretorted chicken stocks made using the recipes listed in the below table, after they had been reheated to 80 °C, and agreed unanimously that there was no significant difference in bitterness. This demonstrates that the retorting process produces unwanted bitter tasting compounds. Further, the compositions in the below table were of comparable sweetness.

Water 96.43 95.93

Chicken 0.39 0.39

Sugar 0.1 1 0.1 1

Salt 0.72 0.72

Potato starch 0.1 1 0.1 1

Wheat flour 0.96 0.96

Maltodextrin 0.68 0.68

Flavourings 0.59 0.59

Colours 0.01 0.01

Glycerol 0.0 0.5 Example 5: Beef stock with glycerol added prior to retorting

Beef stocks were made using the recipes listed in the below table. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

The stock with 0.5% glycerol included prior to retorting gave a reduction in bitterness in comparison to the stock with no glycerol present prior to retorting. The stock with 0.5% glycerol also gave a much rounder and enhanced flavour with stronger meaty flavours.

Example 6: Beef gravy with glycerol added prior to retorting

Beef gravies were made using the recipes listed in the below table. Each gravy was sealed within a retortable pouch, then retorted. The gravies were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

Water 86.79 86.29

Modified maize

starch 3.33 3.33

Beef 5.00 5.00

Rapeseed oil 1 .85 1 .85

Garlic 0.80 0.80

Flavourings 2.23 2.23 Glycerol 0.0 0.5

The gravy with 0.5% glycerol included prior to retorting gave a reduction in bitterness in comparison to the gravy with no glycerol present prior to retorting. The gravy with 0.5% glycerol also gave a much rounder and enhanced flavour with stronger meaty flavours.

Example 7: Chicken gravy with glycerol added prior to retorting

Chicken gravies were made using the recipes listed in the below table. Each gravy was sealed within a retortable pouch, then retorted. The gravies were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

The gravy with 0.5% glycerol included prior to retorting gave a reduction in bitterness in comparison to the gravy with no glycerol present prior to retorting. The gravy with 0.5% glycerol also gave a much rounder and enhanced flavour with stronger meaty flavours.

Example 8: Chicken gravy with glycerol added prior to retorting

Chicken gravies were made using the recipes listed in the below table. Each gravy was sealed within a retortable pouch, then retorted. The gravies were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

Water 91 .04 90.54 Modified maize starch 4.27 4.27

Chicken 0.4 0.4

Sunflower oil 0.4 0.4

Sugar 0.56 0.56

Salt 0.68 0.68

Herbs and vegetable

pieces 0.65 0.65

Flavourings 2.00 2.00

Glycerol 0.0 0.5

The gravy with 0.5% glycerol included prior to retorting gave a reduction in bitterness in comparison to the gravy with no glycerol present prior to retorting. The gravy with 0.5% glycerol also gave a much rounder and enhanced flavour with stronger meaty flavours.

Example 9: Beef stock with glycerol monostearate (GMS) added prior to retorting Beef stocks were made using the recipes listed in the below table. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

Both of the above stocks with GMS included prior to retorting gave a reduction in bitterness in comparison to the stock with no GMS present prior to retorting.

When using GMS, the product seemed to have white lumps of "fat" evident in the cold product. At 0.5 wt% GMS, these lumps dissolved when the product was reheated for consumption. At 0.94% of GMS, tasters found there was an improvement in flavour, but results indicated that the appearance was less desirable to consumers, as the white lumps of fat did not dissolve when heated to 80 °C. Example 10: Beef stock with glycerol added prior to retorting

Beef stocks were made using the recipes listed in the below table. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

The stock with 0.12% glycerol included prior to retorting gave a reduction in bitterness in comparison to the stock with no glycerol present prior to retorting. This reduction in bitterness was reported as being less than that of the 0.5% glycerol product. Example 1 1 : Beef stock with sorbitol added prior to retorting

Beef stocks were made using the recipes listed in the below table. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences. The samples were assessed by a panel of six tasters at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

Water 95.14 94.64

Beef 0.84 0.84

Sugar 0.58 0.58

Salt 0.71 0.71

Flavourings 2.73 2.73

Sorbitol 0.0 0.5 The stock with 0.5% sorbitol included prior to retorting gave a reduction in bitterness in comparison to the stock with no glycerol present prior to retorting. The stock with 0.5% glycerol also had stronger meaty flavours. Example 12: Unretorted beef stock with sorbitol added prior to retorting

A panel six tasters assessed unretorted beef stocks made using the recipes listed in the below table, after they had been reheated to 80 °C, and agreed unanimously that there was no significant difference in bitterness. This demonstrates that the retorting process produces unwanted bitter tasting compounds. Further, the compositions in the below table were of comparable sweetness..

Example 13: Retorted beef containing chef made stock with glycerol added prior to retorting

Three chef made stocks were prepared, with 0%, 0.5%, and 1 % glycerol respectively. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

The chef made stock with 0% glycerol, when retorted, had an unpleasant bitter processed taste. The stocks with 0.5% and 1 % glycerol included prior to retorting gave a reduction in bitterness in comparison to the stock with no glycerol present prior to retorting. The stocks with 0.5% and 1 % glycerol also gave a pleasant taste, and a desirable mouthfeel.

Example 14: Retorted beef containing chef made stock with sorbitol added prior to retorting Two chef made stocks were prepared, with 0% and 0.5%, sorbitol respectively. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences by a panel of six tasters. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

The chef made stock with 0% sorbitol, when retorted, had an unpleasant bitter processed taste. The stocks with 0.5% sorbitol included prior to retorting gave a reduction in bitterness in comparison to the stock with no sorbitol present prior to retorting. The stocks with 0.5% sorbitol also gave a pleasant taste, and a desirable mouthfeel.

Example 15: Unretorted beef containing chef made stock with added sorbitol

Two chef made stocks were prepared, with 0% and 0.5%, sorbitol respectively. These stocks were not retorted, and these unretorted stocks were then assessed by a panel of six tasters after they had been reheated to 80 °C. The taste of the unretorted chef made stock with 0.5% sorbitol was actually rated as significantly worse by five out of six tasters.

Example 16: Beef stock with erythritol added prior to retorting

Beef stocks were made using the recipes listed in the below table. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

The stock with 0.5% erythritol included prior to retorting gave a reduction bitterness in comparison to the stock with no erythritol present prior to retorting. Further in contrast to other polyols that were tested, erythritol gave a stronger savoury and yeast flavour notes than pure beef flavour notes.

Example 17: Unretorted beef stock with added erythritol

A panel of tasters assessed unretorted beef stocks made using the recipes listed in the below table, after they had been reheated to 80 °C, and agreed unanimously that there was no significant difference in bitterness. This demonstrates that the retorting process produces unwanted bitter tasting compounds. Further, the compositions in the below table were of comparable sweetness.

Example 18: Beef stock with isomalt added prior to retorting

Beef stocks were made using the recipes listed in the below table. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

The stock with 0.5% isomalt included prior to retorting gave a reduction in bitterness in comparison to the stock with no isomalt present prior to retorting. The specific flavour profile of the stock with 0.5% isomalt had an initial sweetness followed by a salty flavour, with a short-lasting beef aftertaste.

Example 19: Unretorted beef stock with added isomalt

A panel of tasters assessed unretorted beef stocks made using the recipes listed in the above table, after they had been reheated to 80 °C, and agreed unanimously that there was no significant difference in bitterness. This demonstrates that the retorting process produces unwanted bitter tasting compounds. Further, the compositions in the above table were of comparable sweetness.

Example 20: Beef stock with xylitol added prior to retorting

Beef stocks were made using the recipes listed in the below table. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

The stocks with 0.5% xylitol and 1 % xylitol included prior to retorting gave a reduction in bitterness in comparison to the stock with no xylitol present prior to retorting. The stock with 0.5% xylitol gave the most effective reduction in bitterness. Further, the stock with 0.5 wt% xylitol had a strong beef aftertaste. The 1 % xylitol stock tasted the sweetest of the three samples, but still maintained a good flavour profile.

Example 21 : Unretorted beef stock with added xylitol

A panel of tasters assessed unretorted beef stocks made using the recipes listed in the below table, after they had been reheated to 80 °C, and agreed unanimously that there was no significant difference in bitterness. This demonstrates that the retorting process produces unwanted bitter tasting compounds. Further, the compositions in the below table were of comparable sweetness.

Example 22: Beef stock with maltitol added prior to retorting

Beef stocks were made using the recipes listed in the below table. Each stock was sealed within a retortable pouch, then retorted. The stocks were then assessed for flavour differences. The samples were assessed at a temperature of at least 80 °C to ensure the detection of any undesirable volatiles present.

The stock with 0.5% maltitol included prior to retorting gave a reduction in bitterness in comparison to the stock with no maltitol present prior to retorting. However, the tasters reported that the reduction in bitterness was not as improved as compositions with glycerol included prior to retorting.