Description:FIELD OF THE INVENTION

The present invention relates to a solid curing agent comprising Swiss chard; sodium chloride and at least one excipient. The present invention particularly relates to a stable solid curing agent in powdered or granular form comprising Swiss chard juice concentrate and sodium chloride with at least one excipient.

The present invention also relates to a process for preparing a solid curing agent comprising a Swiss chard juice concentrate; sodium chloride and at least one excipient. The present invention particularly relates to the process for preparing the stable solid curing agent in powdered or granular form comprising Swiss chard juice concentrate and sodium chloride with at least one excipient.

BACKGROUND OF THE INVENTION
The preservation of meat and meat products has been practiced in a variety of ways, such as by smoking, treatment with salt or nitrite, or combinations thereof. Curing meat products is an ancient strategy to preserve muscle foods for long periods. Nowadays, cured meat products are widely produced using nitrate and nitrite salts. Bacteria or other organisms that can convert the nitrate to nitrite are then added to the mixture of the meat or meat product to be cured and the nitrate-containing substance to ferment the nitrate to nitrite. The presence of nitrite gives the meat a distinct colour and flavour, in addition to preventing the growth of harmful microorganisms. Advancements in this field have resulted in readily available nitrite containing liquid concentrates from various plant materials such as celery, beet, cabbage, radish, onion and chicory leaf. However, a disadvantage is that liquid agents are difficult to use, transport.

There are various patent and non-patent literature available for meat curing has been discussed.

US2021092952A1 discloses a process of producing an antimicrobial powder, the process comprising the steps of combining a hygroscopic ingredient and a low molecular weight antimicrobial organic acid in an aqueous solution to obtain a liquid slurry composition and drying the liquid slurry composition to produce an antimicrobial powder.

US2014242217A1 relates to an isolated and natural curing agent comprising a plant-based nitrite and an organism, the plant-based nitrite being derived from a plant material comprising at least about 50 ppm nitrate, the organism inactivated, wherein the organism was capable of converting nitrate to nitrite before the inactivation, and wherein the curing agent being capable of curing a meat or meat product.

KR20200075232A relates to an additive using natural materials for meat product application to replace synthetic nitrite, wherein the additive is a fermentation broth comprising red Swiss chard fermentation broth, maltodextrin, and 20 to 90mL/L of nitrite, wherein the fermentation broth comprises a fermented powder of red Swiss chard pulverized by a spray drying process.

Literature titled Beta vulgaris as a Natural Nitrate Source for Meat Products: A Review discloses the main nitrate sources among Beta vulgaris varieties and the strategic use of their liquid and powder extracts in the production of cured meat products. [Beta vulgaris as a Natural Nitrate Source for Meat Products: A Review; Paulo E. S. Munekata, Mirian Pateiro et al; Journal -Foods Vol 10 (9); 4 September 2021.]

The curing processes described in the prior art present several problems such as number of processing steps involved, process of converting nitrate to nitrite require microbial organisms and additional processing time, thus slowing the overall process. Also, the Swiss chard juice concentrate is unstable and nitrite content present therein degrades on storage or when kept at room temperature. Thus, there is a need in the art for a commercially viable product and process for preserving or curing meat and meat products which eliminates the few problems outlined above.

The inventors of the present invention have successfully addressed the existing drawbacks and formulated a solid curing agent containing plant-based nitrite derived from a concentrated liquid juice particularly a Swiss chard juice concentrate. The inventors of the present invention have developed a solid stable salt composition comprising a Swiss chard juice concentrate combined with an inert carrier like sodium chloride and at least one excipient. The composition of the present invention has been able to overcome the stability issue of Swiss chard juice concentrate by formulating a solid composition having not only longer shelf life; but also acts as a taste modifier due to presence of salt in the composition. The salt composition of the present invention is formulated using easy and commercially viable processing steps which help prepare a stable solid composition which not only cures meat or meat products but also adds to the taste of the food product. The salt composition of the present invention is stable on storage, exhibits excellent solid stability, longer shelf life and is easy to pack and store.

To summarize, the inventors of the present invention formulated a stable solid curing agent in powdered or granular form comprising Swiss chard juice concentrate, sodium chloride and at least one excipient having excellent stability and longer shelf life. The composition of the present invention is also easy to pack, store and use for curing meat or other food products.

OBJECTIVE OF THE INVENTION

An objective of the invention is to design and develop stable solid salt composition comprising Swiss chard.
Yet another objective of the present invention is to provide a stable solid salt composition comprising a Swiss chard juice concentrate with stable nitrite content.
Yet another objective of the present invention is to provide the powder/granular composition having excellent solid-state stability, longer shelf life, which is easy to package, storage and convenient for end use.

SUMMARY OF THE INVENTION
The present invention relates to a solid salt composition comprising a plant-based nitrite derived from a liquid juice concentrate obtained from plant material selected from Swiss chard. The present invention particularly relates to a stable solid curing agent in powdered or granular form comprising Swiss chard juice concentrate, sodium chloride with at least one excipient.

The present invention relates to the process for preparing the stable solid curing agent in powdered or granular form comprising Swiss chard juice concentrate and sodium chloride with at least one excipient. The process involved in preparing the stable solid curing agent includes:
• Providing a Swiss chard juice concentrate, sodium chloride and adding excipients to facilitate the formation of a free-flowing final product.
• Loading of the liquid concentrate obtained from the plant material Swiss chard with sodium chloride solution and suitable excipients such as calcium silicate, hydroxypropyl methyl cellulose (HPMC), modified starch, calcium oxide and magnesium stearate using suitable unit operations like blending, spray granulation, fluid bed processing/granulation and spray drying or a combination of these processes.
• Drying the final product to a desired moisture content using a suitable process
• Cooling the product to room temperature before packing in airtight container

DESCRIPTION OF THE DRAWINGS:

For a more complete understanding of the invention, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawings and described by way of embodiments of the invention.

Figure 1: Typical process flow chart depicting the broad manufacturing flow of stable solid curing granular/powdered agent.

Figure 2: Observation for Swiss chard salt product in open pack at 25oC/75%RH storage condition

DETAILED DESCRIPTION OF THE INVENTION

In describing the embodiment of the invention, specific terminology is chosen for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected, and it is to be understood that such specific terms include all technical equivalents that operate in a similar manner to accomplish a similar purpose. As used herein, reference to an element by the indefinite article “a” or “an” does not exclude the possibility that more than one of the elements is present, unless the context clearly requires that there is one and only one of the elements. The disclosure of numerical ranges should be understood as referring to each discrete point within the range, inclusive of endpoints, unless otherwise noted. The term “about” as used in the disclosure of numerical ranges indicates that deviation from the stated value is acceptable to the extent that the deviation is the result of measurement variability and/or yields a product of the same or similar properties.

As used herein, and unless otherwise indicated, the term “liquid juice concentrate obtained from a plant material” as used herein refers to an aqueous liquid juice concentrate that may be in a concentrated or dilute form comprising the curing agent preferably nitrite and may have a solid content varying from about 40% to 65% w/w, obtained from the plant material of Swiss chard. The Swiss chard juice concentrate as used in the present invention is procured as dark green/brown liquid from Bavaria Corporation International, Florida (US).

The term “granulation” refers to a process of converting the powder into granules employing suitable process or a combination of processes with the aid of commonly used equipment like a rotary mixer granulator, blender, coater, spray granulation, spray drying or a combination thereof.

According to an embodiment, the present invention relates to a solid composition comprising a plant-based nitrite derived from a liquid juice concentrate obtained from plant material selected from the group consisting of celery, beet, cabbage, Swiss chard, cucumber, eggplant, mushroom, lettuce, squash, zucchini, mixed salad greens, carrot, artichoke, green beans, lima beans, broccoli, cauliflower, collard greens, corn, mustard, okra, onion, Chinese pea pods, black eyed peas, green peas, potatoes, turnips, radishes, and combinations thereof.

According to an embodiment, the present invention relates to a solid curing agent comprising a Swiss chard juice concentrate; sodium chloride and at least one excipient.

According to an embodiment, the present invention particularly relates to the stable solid curing agent in powdered or granular salt form comprising Swiss chard juice concentrate and sodium chloride with at least one excipient.

According to another embodiment, the present invention particularly relates to the stable solid composition in powdered or granular form comprising Swiss chard juice concentrate and sodium chloride with atleast one excipient which is suitably used as a preservative in e.g., processing and curing of meat product. The composition of the present invention is used to preserve or cure meat or meat products and also has other applications in the food industry.

According to an embodiment, the concentration of Swiss chard juice concentrate present in the solid composition of the present invention may range from 40% to 65%w/w of the composition. According to a further embodiment, the concentration of Swiss chard juice concentrate present in the solid composition of the present invention may range from 45% to 65%w/w of the composition.

According to an embodiment, the content of sodium nitrite in the composition of the present invention may vary between 15000 to 25000 ppm.
As per the preferred embodiment of the present invention, the content of sodium nitrite in the Swiss chard composition may vary between 19000 to 24000 ppm.

According to important embodiment of the present invention, the stable solid curing agent of the present invention includes sodium chloride.
According to a further embodiment, the concentration of sodium chloride present in the solid composition of the present invention may range from 30% to 50%w/w of the composition. According to a further embodiment, the concentration of sodium chloride present in the solid composition of the present invention is about 35% to 50%w/w of the total composition.
Sodium chloride when added to the liquid Swiss chard juice concentrate enhances the taste of food made out of preserved and cured meat, thus sodium chloride salt apart from preserving meat also acts as a taste modifier.

According to an embodiment, at least one excipient in the solid curing agent composition of the present invention includes calcium silicate, cellulose polymer such as hydroxypropyl methyl cellulose, modified starch, calcium oxide, magnesium stearate or combination thereof. According to an embodiment, at least one excipient in the solid curing agent composition of the present invention particularly may include calcium silicate. The excipients used in the stable curing agent composition of the present invention are commercially manufactured and sourced through various suppliers. The excipients employed in the present invention are commonly used in various processes in pharmaceutical, nutraceutical or food industry, as processing aids, to facilitate the preparation of products, formulations or compositions.

According to another embodiment, the excipients are present in the range of 1% to 10% by weight of the composition, particularly in the range of 1% to 6% by the weight of the composition.

According to an embodiment, the particle size of the solid curing agent composition of the present invention is in the range of 50 to 1000 micron.
According to another embodiment, the particle size of the solid curing agent composition of the present invention particularly is in the range of 100 to 700 micron.

According to an embodiment, the bulk density of the solid curing agent composition of the present invention is in the range of 0.20 to 0.80 g/ml. According to another embodiment, the bulk density of the solid curing agent composition of the present invention is particularly in the range 0.40 to 0.50 g/ml.

According to an embodiment, the present invention relates to a process for preparation of the stable solid curing agent in powdered or granular form comprising Swiss chard juice concentrate and sodium chloride with at least one excipient.

The process for preparation may include the following steps:
Swiss chard juice concentrate may be passed through suitable sieve. Sodium chloride may be dissolved in water under continuous stirring to prepare a solution of sodium chloride.
Filtered liquid Swiss chard juice concentrate may be added to sodium chloride solution under stirring, following to which further excipients such as calcium silicate may be added to the system to get the slurry.
The slurry may be subjected to spray drying at specific temperature conditions till a loss on drying (LOD) value of 3-5% is achieved.
The product may be subjected to water granulation using a planetary mixer or blender and dried using till a loss on drying (LOD) value of 2-5% is achieved to get granules.
The excipient such as calcium silicate may be added as a processing aid to this granulated mass and the mixture is allowed to cool to room temperature and the finished product may be packed in airtight container away from moisture.

The inventors of the present invention found that the composition of the present invention comprising of Swiss chard juice concentrate with sodium chloride and at least one excipient is stable, exhibits longer shelf life and is easy to pack and store. The inventors of the present invention were successful in overcoming the stability issue of Swiss chard juice concentrate by formulating a solid composition having not only a longer shelf life but also acts as a taste modifier due to presence of salt in the composition. The composition of the present invention is also easy to pack and store for curing meat or other food products.

Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosed embodiments. The following examples should be considered as exemplary only, with a true scope and spirit of the present disclosure being indicated by the claims.

Preparatory Examples:
The invention using a process as depicted in Fig 1 is further illustrated by the following non-limiting examples.

Example 1: Preparation of Curing agent containing Swiss chard (Nitrite content 21,090 ppm)
Ingredients Quantity (%w/w)
Swiss chard juice concentrate 54.32
Sodium chloride 42.25
Hydroxypropyl methyl cellulose (HPMC) 2.28
Calcium silicate 1.15

The manufacturing process described in general in Figure 1 was broadly followed with very minor modifications if needed to arrive at a product which was granular, and free flowing. Hydroxypropyl cellulose was added during the step of slurry preparation and the mixture was subjected to spray drying process.
The composition is light to dark brown colour product having particle size in the range of 100 to 600 microns and bulk density of about 0.41 g/ml. The product is granular and free flowing.

Analysis of the nitrite content in samples: AOAC Official Method 935.48, AOAC Official Method 993.03 are the methods that were used to analyse the nitrite content in the samples. Since the curing effect is mediated through the nitrite content in Swiss chard, the inventors analysed the nitrite content in the finished product which is the stable solid composition of Swiss chard juice concentrate and results obtained are given in examples 1 to 8 of the present invention.

Example 2: Preparation of Curing agent containing Swiss Chard (Nitrite content 21,043 ppm)
Ingredients Quantity (%w/w)
Swiss chard juice Concentrate 54.32
Sodium chloride 41.97
Modified starch 1.71
Calcium silicate 2

The manufacturing process described in general in Figure 1 was broadly followed with very minor modifications if needed to arrive at a product which was granular, and free flowing.
Modified starch was added during the step of slurry preparation and the mixture was subjected to spray drying process.
The composition is light to dark brown colour product having particle size in the range of 200 to 600 microns and having bulk density of about 0.44 g/ml.

Example 3: Preparation of Curing agent containing Swiss chard (Nitrite content 23,046 ppm)

Ingredients Quantity (%w/w) on Drying
Swiss chard juice concentrate 56.53
Sodium chloride 38.47
HPMC 2
Calcium silicate 3

The manufacturing process described in general in Figure 1 was broadly followed with very minor modifications if needed to arrive at a product which was granular, and free flowing.
Modified starch was added during the step of slurry preparation and the mixture was subjected to spray drying process.
The composition is light to dark brown colour product having particle size in the range of 100 to 700microns and having bulk density of about 0.40g/ml.

Example 4: Preparation of Curing agent containing Swiss chard (Nitrite content 21,100 ppm)
Ingredients Quantity (%w/w)
Swiss Chard juice Concentrate 56
Sodium chloride 42
Calcium silicate 2

The manufacturing process described in general in Figure 1 was broadly followed with very minor modifications if needed to arrive at a product which was granular, and free flowing.
The composition is light to dark brown colour product having particle size in the range of 200-700microns and having bulk density of about 0.42 g/ml.

Example 5: Preparation of Curing agent containing Swiss chard (Nitrite content 19,109 ppm)

Ingredients Quantity (%w/w)
Swiss Chard juice Concentrate 50
Sodium chloride 48
Calcium silicate 2

The manufacturing process described in general in Figure 1 was broadly followed with very minor modifications if needed to arrive at a product which was granular, and free flowing. The composition is light to dark brown colour product having particle size in the range of 150 to 600microns and bulk density of about 0.42 g/ml.

Example 6: Preparation of Curing agent containing Swiss chard (nitrite content 21,917 ppm)

Ingredients Quantity (%w/w)
Swiss chard juice concentrate 58.13
Sodium chloride 38.87
HPMC 0.50
Calcium oxide 0.50
Calcium silicate 2

The manufacturing process described in general in Figure 1 was broadly followed with very minor modifications if needed to arrive at a product which was granular, and free flowing.
Hydroxypropyl methyl cellulose (HPMC) and calcium oxide were added during the step of slurry preparation and the mixture was subjected to spray drying process.
The composition is light to dark brown colour product having particle size in the range of 200-700microns and having bulk density of about 0.41 g/ml.

Example 7: Preparation of Curing agent containing Swiss Chard (nitrite content 21,334 ppm)

Ingredients Quantity (%w/w)
Swiss Chard juice Concentrate 58
Sodium chloride 38.5
HPMC 0.50
Calcium oxide 0.33
Calcium silicate 2
Magnesium stearate 0.67

The manufacturing process described in general in Figure 1 was broadly followed with very minor modifications if needed to arrive at a product which was granular, and free flowing.
Hydroxypropyl methyl cellulose (HPMC) and calcium oxide were added during the step of slurry preparation and the mixture was subjected to spray drying process; while magnesium stearate was added towards the end of the process, before packaging the product.
The composition is light to dark brown colour product having particle size in the range of 100 to 700microns and bulk density of about 0.45 g/mL.

Example 8: Preparation of Curing agent containing Swiss chard (nitrite content 23,371 ppm)

Ingredients Quantity (%w/w)
Swiss chard juice concentrate 62.04
Sodium chloride 35.96
Calcium silicate 2

The manufacturing process described in general in Figure 1 was broadly followed with very minor modifications if needed to arrive at a product which was granular, and free flowing. The composition is light to dark brown colour product having particle size in the range of 200 to 600microns and bulk density of about 0.48mg/ml.

Example 9: Stability study for the curing agent containing Swiss chard
Stress study was conducted using composition of the present invention as specified in Example 8. The composition was packed in double LDPE bag in tri laminated pouch with 1 gm desiccant added in-between the two bags. The study indicated stability of the product against the stress condition and the results are mentioned in Table 1.

Table 1: Result of accelerated studies in packed conditions
Curing agent containing Swiss chard (Example 8) observations 40°C/75% RH- Non modified atmospheric packing 40°C/75% RH- packing with Oxygen gas.
Avg. Sodium nitrite (ppm) % LOD pH Avg. Sodium nitrite % LOD pH
Initial observations 23371.9 2.76 9.88 23371.9 2.76 9.88
14 Days observations 23561.1 3.78 9.98 22434.9 3.63 9.8
21 Days observations 21930.3 2.25 10.36 22777.3 2.89 9.98
28 Days observations 22930.8 3.89 9.57 23056 3.02 10.12
35 Days observations 23996.2 3.09 9.52 23812 2.91 9.85

Other stress condition test observations.

Swiss Chard Salt Powder (Example 8) observations Avg. Sodium nitrite (ppm) % LOD pH
Air fluidization-85°C/15 min 24199.1 1.84 10.12
Microwave heating- 80°C/till pungent yellowish gas evolves 22023.7 2.06 10.82
Hot air Oven Heating (70°C/3hr) 22200.5 2.12 10.03

Based on the observations of stability as shown in Table 1 and Figure 2, it was seen that the product does not absorb any moisture when exposed to the conditions of higher inherent moisture level and percent relative humidity. The nitrite content was also found to be stable during the study, indicating important advantage of the solid formulation of the present invention. The composition was also found to be stable at room temperature when packed in airtight container. There was no discoloration or liquefaction of the product, which was packed in airtight container.
Furthermore, it was noted that the nitrite content is the main cause of instability of formulations containing liquid Swiss chard which is also stable when formulated in solid form with sodium chloride.
In addition, irrespective of the variations that occur during storage and transportation, use of the product remains stable.
Since the composition is stable, the uniform dispersion in water comprising the curing agent can be used directly as a curing agent by spraying the filtrate directly onto meat products or use of the filtrate directly in the food depending on the desired concentration.

Stability Study Result: Stability study was conducted on composition of the present invention as mentioned in Example 8 at accelerated and intermediate conditions for a period of one month which is as mentioned in Table 2.
Table 2: Stability study of sample from Example 8 at accelerated and intermediate conditions
Condition Month Sodium Nitrite (ppm) Appearance Odour pH %LOD
Initial 0 23371.9 Light to dark brown colour free flowing granular powder. Characteristic 9.88 2.76
40°C/75%RH accelerated condition 1 23561.0 Light to dark brown colour free flowing granular powder. Characteristic 9.57 3.63
40°C/75%RH accelerated condition 2 23818.4 Light to dark brown colour free flowing granular powder. Characteristic 9.56 2.34
40°C/75%RH accelerated condition 3 24235.7 Light to dark brown colour free flowing granular powder. Characteristic 9.69 3.10
30 °C/75%RH
Control condition 1 23109.1 Light to dark brown colour free flowing granular powder. Characteristic 10.68 3.19
30 °C/75%RH
Control condition 2 24776.7 Light to dark brown colour free flowing granular powder. Characteristic 9.81 3.07

The study as mentioned in Table 2 indicated that the product is stable for period of three month at accelerated and intermediate conditions. Further it was observed that the composition and the process of the present invention helps to extend the shelf life of the product up to 2 years.

Technical Advancements:
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of:
• Easy to store, use & handle the product for longer time.
• Liquid Swiss chard juice concentrate is perishable commodity that become unusable in a day. However, new process helps to extend its shelf life up to 2 years. Shelf life of liquid Swiss chard as a preservative & aromatic compound increases many folds.
• Curing agent of the present invention enhances the taste of meat product after cooking.
, Claims:We claim,

1. A solid composition comprising a Swiss chard juice concentrate, sodium chloride and at least one excipient.
2. The solid composition as claimed in claim 1, wherein the nitrite content is between 15000 to 25000 ppm.
3. The solid composition as claimed in claim 1, wherein Swiss chard juice concentrate is present in the concentration of 40% to 65% by weight of the composition.
4. The solid composition as claimed in claim 1, wherein sodium chloride is present in the concentration of 30% to 50% by weight of the composition.
5. The solid composition as claimed in claim 1, wherein at least one excipient is selected from calcium silicate, hydroxypropyl methyl cellulose, modified starch, calcium oxide and magnesium stearate.
6. The solid composition as claimed in claim 1, wherein at least one excipient is present in the concentration of 1% to 10% by weight of the composition.
7. The solid composition as claimed in claim 1, wherein the bulk density of the composition is 0.40 g/ml to 0.45 g/ml.
8. The solid composition as claimed in claim 1, wherein the particle size of the composition ranges from 100 to 700 microns.
9. The solid composition as claimed in claim 1, wherein the composition is stable and exhibits longer shelf life.
10. The solid composition as claimed in claim 1, wherein the process for preparation of the composition includes:
Step a: Adding filtered liquid Swiss chard juice concentrate to sodium chloride solution under stirring and further adding at least one excipient to the mixture.
Step b: Drying the slurry using suitable equipment such as spray dryer.
Step c: Optional granulation of the dried power at a suitable speed and time.
Step d: Drying the granules.
Step e: Addition of at least one excipient as a processing aid to the granulated mass as a lubricant and packaging the product in airtight container away from moisture.