CONCENTRATED FOOD PRODUCT AND METHOD FOR PREPARING SAME

Abstract

The present invention relates to methods for preparing a powdered food product and powdered food products obtainable by the methods. There are also disclosed methods for preparing a food stock and food stocks obtainable by the methods, as well as methods for preparing a food broth, food broths obtainable by the methods, and a device for preparing such food broths. The methods and products obtainable by the methods find utility in the culinary field of preparing stocks and broths.

Claims

1. A method for preparing a powdered food product, the method comprising the steps of: (a) cooking a food source by baking, roasting, frying, grilling, barbecuing, smoking, steaming, braising, or any combination each thereof; (b) dehydrating the cooked food source; and (c) reducing the particle size of the dehydrated food source.

2. A method according to claim 1, wherein the cooking step comprises heating the food source to at least 150 C.

3. A method according to claim 1, wherein the food source is a meat source and the meat source comprises meat and bones.

4. A method according to claim 1, wherein the dehydrating step comprises dehydrating the food source to a moisture content of less than 25% relative dry weight of the cooked food source.

5. A method according to claim 1, wherein the dehydrating step comprises dehydrating the food source to a water activity (a.sub.w) of less than 0.9.

6. A method according to claim 1, wherein the reducing step comprises reducing the particle size of the dehydrated food source to a particle size of less than 10 mm.

7. A method according to claim 1, wherein the method further comprises the steps of separating the meat from the cooked food source; dehydrating the cooked meat; and reducing the particle size of the dehydrated meat.

8. A method according to claim 1, wherein the method further comprises the steps of separating the bones from the cooked food source; dehydrating the cooked bones; and reducing the particle size of the dehydrated bones.

9. A method for preparing a food stock, the method comprising the steps of: (a) providing a powdered food product directly obtained from a method according to claim 1; and (b) adding fat to the powdered food product.

10. A method according to claim 9, wherein the fat is added in an amount of at least 10% (w/w) of the powdered food product.

11. A method according to claim 9, wherein the fat is added in an amount of at least 100% (w/w) of the powdered food product.

12. A method according to claim 9, wherein the method comprises the additional step of reducing the particle size of the powdered food product and added fat to a particle size of 30-120 microns (m).

13. A method for preparing a food broth, the method comprising the steps of: (a) providing a powdered food product directly obtained from a method according to claim 1; (b) providing a solvent; and (c) infusing the powdered food product in the solvent.

14. A device for preparing a food broth, the device comprising: (a) a powdered food product directly obtained from a method according to claim; and (b) a porous membrane encapsulating the powdered food product.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0214] Embodiments of the present invention will now be described with reference to the accompanying drawings in which:

[0215] FIG. 1 is a graph illustrating the effect of the dehydrating step of a method according to a first aspect of the present invention;

[0216] FIG. 2 is a photograph depicting a device according to a seventh aspect of the present invention;

[0217] FIG. 3 is a photograph depicting preparing a food broth according to a fifth aspect of the present invention; and

[0218] FIGS. 4A and 4B are each a graph illustrating the effect of the dehydrating step of a method according to a first aspect of the present invention.

EXAMPLES

[0219] Embodiments of the present invention will now be described with reference to the following non-limiting examples:

Example 1

[0220] Preparing a Powdered Food Product

[0221] All culinary ingredients were commercially sourced from traditional (high street) grocery stores or supermarkets, unless otherwise indicated.

[0222] 1.4 kg of raw chicken carcass (back and chest cavity) was commercially sourced and placed in an oven tray and roasted in an oven (Rational CombiMaster Plus, Model CMP 61, 11.0 kW) for 40 minutes at 180 C. The cooked bones were removed and minced through a 6 millimetre mincer plate (Trespade, 22 EL Plus, 1.0 kW). The minced cooked bones were seasoned with 11.5 g of a seasoning mixture per 1 kg bones and returned to the oven. The seasoning mixture comprised 2 g onion, 1.5 g garlic powder, 1 g thyme, 1 g organum, 1 g white pepper, and 5 g salt. The seasoned bones were further cooked for a further 30 minutes at 140 C. and yielded 0.5 kg of dehydrated bones. The dehydrated bones were transferred to a kitchen bowl chopper (RobotCoupe, R4 1500, 4.5 L) and reduced in particle size until the powdered food product had a particle size of less than 3 mm, as measured using a particle size analyser (Grindometer-Elcometer 2020M002 202013120075) in accordance with the manufacturer's instructions. In short, the particle size analyser and a scraper were heated to a temperature between 40-45 C. in an incubator, after washing, and a small sample of the test material was poured into a test channel of the particle size analyser. The scraper blade was scraped at a steady rate down the length of the test channel with sufficient downward pressure to clean the level surface of a gauge at the test channel but leaving the test channel filled with material to be tested. The particle size is determined by observing the point along the gauge where the material first shows a predominantly speckled appearance and noting graduation marks between which the number of particles, in a band 3 mm wide across the test channel, is in the order of 5-10. The higher graduation figure is noted as particle size. The powdered food product is stored in a cool, dry environment, in an airtight container.

[0223] In a comparative test, 1.4 kg of raw chicken carcass (back and chest cavity) was commercially sourced as above and placed in an oven tray and roasted in an industrial double-door roasting oven (Double D RevoRack) for 90 minutes at 200 C. The cooked bones were removed and minced through a 6 millimetre mincer plate as above. The minced cooked bones were seasoned as above and placed into an oven (Rational CombiMaster Plus, Model CMP 61, 11.0 kW) for a further 30 minutes at 140 C., yieldeding 0.5 kg of dehydrated bones. The dried bones were transferred to a kitchen bowl chopper and reduced in particle size as above.

[0224] The moisture content and water activity of the powdered food product of the invention were each assessed using a moisture analyser (Mettler Toledo, HG63 Halogen) in accordance with the manufacturer's instructions. In short, an empty sample pan was placed in the sample pan handler of the sample chamber, ensuring the tongue of the pan handler fits in the slot of the draft shield element, and the balance installed in the moisture analyzer is set to zero. A small sample of the test material was placed in the sample pan, and the moisture analyser dried and measured the moisture content of the sample.

[0225] The drying curve of FIG. 1 illustrates the effect of dehydrating the cooked food source, which facilitates the step of reducing the particle size of the dehydrated food source, which would otherwise be difficult due to the high moisture content. Without being bound by theory, it is thought that the rate at which the dehydrating step proceeds is less consequential to the method than the moisture content of the food source, which should preferably be less than 25% (relative dry weight of the cooked food source).

[0226] To assess microbiological stability, a 50 g sample of the powdered food product of the invention was stored at typical ambient conditions (25 C., 40% RH), and monitored by an independent lab according to SANS 18593:2004 for microbiological growth of total viable organisms (plate count). After 8 weeks at this temperature and relative humidity, no growth was observed (<10 cfu/g).

Example 2

[0227] Preparing a Food Stock

[0228] A powdered food product was prepared as described in Example 1. 0.4 kg of the powdered food product was mixed with 0.4 kg of rendered chicken fat and dissolved in a 1 L stainless steel vessel using a laboratory dissolver (Dispermill Vango 100-ATP Engineering) at 6 m/s for 30 minutes. The dissolver adaptor was then replaced with a basket mill attachment (Vango 100 Micromill), and the mixture was milled at 2500 rpm (7.8 m/s) for 5 hours, or until a particle size of less than 30 m was attained. The resultant food stock was stored in cool, dry conditions in an air-tight container.

[0229] To assess microbiological stability, a 50 g sample of the food stock of the invention was placed in an incubator (Shel Lab, General Purpose Incubator) at 38 C., 40% RH, and monitored by an independent lab according to SANS 18593:2004 for microbiological growth of total viable organisms (plate count). After 8 weeks at this temperature and relative humidity, no growth was observed (<10 cfu/g).

[0230] The moisture content and water activity were assessed as described above and were determined to be 0.65% and 0.30 respectively.

[0231] The food stock of the invention can be used to prepare a pressed stock cube using the following mixture, which was combined in a stainless steel vessel, warmed to 60 C. in a conventional oven, and pressed into a cube using a hand held moulding tool:

TABLE-US-00001 TABLE 1 Raw Material Quantity (g) Food Stock 20.7 Sage 0.1 Rosemary 0.4 Thyme 0.1 Turmeric powder 0.1 Garlic powder 1.5 Onion powder 1.0 Pepper, white 0.1 Celery powder 0.3 Parsley flakes 0.1 Paprika OR 0.1 Salt 63.4 Yeast Extract 4.8 Emulsifier 2.1 Sugar 5.2 Total 100.0

Example 3

[0232] Preparing a Food Broth and a Device for Preparing Same

[0233] A powdered food product was prepared as described in Example 1, and which can be used to produce a food broth for either direct consumption or for culinary purposes (for example as the base of stews, soups, sauces, etc,) by the addition of boiling water. Because the powdered bones are still of a size that cannot be consumed directly, a device was used to retain the bones during the infusing step. A porous material, such as that used for teabags, is suitable for aqueous extraction with boiling water, and was commercially sourced. 15 g of the following mixture was placed in a 99 cm tetrahedral-shaped bag made from the porous material and sealed using a bar heat sealer, and stored in a cool, dry environment.

TABLE-US-00002 TABLE 2 Raw Material Quantity (g) Powdered food product 62.3 Sage 0.1 Rosemary powder 0.6 Thyme powder 0.2 Turmeric powder 0.1 Garlic powder 2.0 Onion powder 1.3 White pepper powder 0.1 Celery powder 0.4 Parsley flakes 0.1 Paprika oleoresin 0.03 Salt 16.5 Yeast Extract 8.4 Sugar 7.9 Total 100.0

[0234] The bag was placed in a glass measuring jug, and 400 ml of boiling water was added. The powdered food product was allowed to infuse into the water over a period of 5 minutes. The bag was removed and the food broth was used as required.

[0235] As a comparative test, 7.2 g of the mixture defined in Table 2 was placed in a in a quadrilateral-shaped bag made from the porous material and placed in a foil sachet. 4.0 g of instant wheat noodles and 0.75 g of dried chives were added to the sachet. The sachet was sealed using a bar heat sealer and stored in a cool, dry environment. The entire contents of the sachet were emptied into a cup containing 200 ml of boiling water. The powdered food product was allowed to infuse over a 5 minute period, after which the quadrilateral-shaped bag was removed and the food broth was consumed immediately.

Example 4

[0236] Yield from Powdered Food Product and Food Stock of the Invention

[0237] In order to determine the effective strength of the food broth and food stock obtainable from the methods of the invention, as a comparative test, a traditional broth/stock was prepared by an executive chef using 1.0 kg of chicken bones and 3 L of water added to a commercially available pressure cooker and simmered on a stove-top for 5 hours.

[0238] These three stocks were compared using a trained panel of R&D scientists. The traditional broth/stock was was used as a reference standard, and the amount of powdered food product and food stock was increased incrementally under subjective tasting by the trained panel of R&D scientists until the strength of flavour of the three stocks was determined to be the same.

[0239] 5.0 g of the powdered food product of the invention was added to 200 ml of boiling water and allowed to infuse for 5 minutes.

[0240] 1.0 g of the food stock of the invention was added to 200 ml of boiling water and allowed to dissolve for 5 minutes.

[0241] Based on these amounts, it was determined the amount of bones that are required to produce 5.0 g of the powdered food product of the invention and 1.0 g of the food stock of the invention; and thus the amount of bones that are required to achieve a 200 ml stock having the same strength of flavour.

TABLE-US-00003 TABLE 3 Stock Dosage Chicken bone equivalent* Chicken stock 200 ml, as-is 66 g (chef made, without reduction) Powdered food product 5.0 g/200 ml 5.0 g Food stock 1.0 g/200 ml 0.5 g *The amount of meat bone required to produce the indicated amount of meat stock.

Example 5

[0242] Direct Comparison of a Food Stock of the Invention with Market Equivalents

[0243] In order to evaluate the food stock of the invention against traditional market products, two stock cube formulations were developed, each of which is based on the market-leading products in all respects, except the source of chicken flavour. This was done for two different markets, namely the South African and Irish markets. In short, a pressed stock cube was prepared from a food stock of the present invention as described in Example 2, based on the ingredients of the traditional market products, but using the food stock of the invention in place of the source of chicken flavour in the traditional market products

[0244] The pressed stock cubes were each dissolved in water (10 g per 500 ml) and were assessed by consumer panels (22 independent consumers in the South African panel and 18 consumers in the Irish panel), on the basis of; preference (ranking), acceptability (score out of 10), authenticity (score out of 100%) and perception of product value (score out of 100%).

[0245] The following results were obtained:

TABLE-US-00004 TABLE 4 Market Market Sample Leading Sample Leading Product Product Product Product (South Africa) (South Africa) (Ireland) (Ireland) Preference Preferred Preferred Acceptability 6.9 4.6 8.2 6.2 Flavour 68% 32% 65% 35% Authenticity Perception of 55% 9% 60% 30% product value

Example 6

[0246] Comparing a Pwdered Food Product

[0247] To compare the powdered food product of the present invention with a known similar food product, a direct comparative test was conducted. All culinary ingredients were commercially sourced from traditional (high street) grocery stores or supermarkets, unless otherwise indicated.

[0248] For the powdered food product of the present invention, a powdered food product was prepared in accordance with Example 1.

[0249] The chart in FIG. 4A shows the drying curve for the powdered food product of the present invention over the course of the three drying steps (without the intervals standing at ambient temperature).

[0250] For the known similar food product, 50 g of fresh celery, 50 g of fresh onion, and 50 g of fresh carrot were each commercially sourced, placed in a kitchen bowl chopper (RobotCoupe, R4 1500, 4.5 L), and the ingredients were chopped using a blade attachment for 5 min. 500 g of raw chicken breast meat was commercially sourced, placed in the kitchen bowl chopper with the chopped ingredients and further chopped using a blade attachment for 10 min until a paste was formed. 50 g of chicken extract powder (a dried extract made from chicken meat i.e. a powdered chicken broth was commercially sourced, placed in the kitchen bowl chopper with the ingredient paste and further chopped using a blade attachment for 2 min until a fine paste was formed. The fine paste mixture was stuffed into a water proof sausage casing (Crown National), autoclaved at 95 C. for 30 min, and stored at 4 C. in a conventional double sliding door refrigerator (Just Refrigeration Products Model MPM1140SDE) overnight to form a solid mass. Then, the casing was removed and the solid mass was placed in an air drying oven (EchoTherm Benchtop Incubator) at 70 C. for 12 hours. The moisture content was measured at frequent intervals as described above. After 12 hours at 70 C., the solid mass was allowed to stand at ambient temperature (25 C.) for 12 hours. The solid mass was placed in the air drying oven at 60 C. for 12 hours. The moisture content was measured at frequent intervals. After 12 hours at 60 C., the solid mass was allowed to stand at ambient temperature (25 C.) for 12 hours. The solid mass was sliced thinly (ca 1 mm) and dried at 60 C. for 4 hours.

[0251] The chart in FIG. 4B shows the drying curve for the known similar food product sausage over the course of the three drying steps (without the intervals standing at ambient temperature).

Example 7

[0252] Direct Comparison of a Food Stock of the Invention with Market Equivalents

[0253] In order to evaluate the food stock of the invention against traditional market products, two stock cube formulations (Sample Products 1 and 2) were developed, each of which is based on the market-leading products in all respects, except the source of chicken flavour. In short, a pressed stock cube was prepared from a food stock of the present invention as described in Example 2 based on the ingredients in Table 5 below and using the food stock of the invention in place of the source of chicken flavour in the traditional market products.

TABLE-US-00005 TABLE 5 Sample Product Sample Product Ingredients 1 (% w/w) 2 (% w/w) Powdered food product of Example 1 20.00 Food broth of Example 3 10.00 Vegetable fat (mp 48) 12.00 14.50 Turmeric powder 0.63 0.63 Celery powder 0.63 0.63 White pepper powder 0.25 0.25 Salt 40.70 40.70 Potato starch 5.29 12.79 Sugar 5.00 5.00 Yeast extract 13.00 13.00 Onion Flavouring 2.50 2.50 100.00 100.00

[0254] Three pressed stock cubes were each dissolved in water (10 g per 450 ml) to form a food broth.

[0255] Additionally, a traditional soup was prepared from the formed food broth, the soup comprising 500 ml of the food broth, 100 g of chicken breast sliced very thin, 1 teaspoon light soy sauce, teaspoon freshly grated ginger, teaspoon freshly grated garlic, 1 teaspoon sesame oil, 1 tablespoon corn flour, 60 ml water, and salt and pepper to taste. In short, the formed food broth and chicken were placed in a saucepan (1 Litre) and brought to the boil over high heat. The heat was reduced to low and simmered for 5 minutes or until the chicken was cooked through. The chicken was transferred to a heatproof bowl, set aside for 5 minutes to cool slightly, and finely shredded. The soy sauce, garlic and ginger were added to the consomme mixture. The cornflour was placed in a small bowl and the water was gradually stirred in until smooth and combined. The cornflour mixture was gradually stirred into the consomme mixture, which was then cooked, stirring occasionally, for 2 minutes or until consomme thickened slightly and cooked for 2 minutes or until hot. The sesame oil was added and seasoned with salt and pepper.

[0256] Each of the food broth and soup were assessed by consumer panels (24 Regular Chicken Stock Consumers), on the basis of; preference, intensity of aroma and taste, taste like real chicken, and overall appeal (word matrix); each on a scale of 1-10.

[0257] The following results were obtained:

TABLE-US-00006 TABLE 5 Sample Product Sample Product Market Leading 1 2 Product Aroma Intensity 3.9 3.1 3.2 Assessed in a Food Broth Aroma Intensity 4.5 3.6 2.9 Assessed in a Soup Taste Intensity 4.5 8.4 3.3 Assessed in a Food Broth Taste Intensity 5.2 5.4 3.2 Assessed in a Soup Chicken Taste 3.6 3.3 2.4 Assessed in a Food Broth Chicken Taste 5.2 5.0 2.8 Assessed in a Soup Preference 14/23 (60.9%) 4/23 (17.4%) 5/23 (21.7%) (Food Broth) Preference 7/23 (30.4%) 15/23 (65.2%) 1/23 (4.3%) (Soup)

[0258] Accordingly, the present invention provides methods for preparing a powdered food product and food stocks for use in the culinary field, and which display improved properties compared to traditionally prepared broths/stocks in terms of microbiological shelf-life and yield. The food stocks of the present invention display improved microbiological shelf-life properties compared to traditional meat stocks. The food stocks of the present invention, incubated at 38 C. for 8 weeks, showed no sign of microbiological growth, whereas traditional meat stocks need to be frozen to achieve this shelf-life. It is also evident that both the powdered food product and food stock of the present invention are much higher yielding based on the amount of meat bone required to produce a standard volume of traditional meat stock.