NL2017441B1

NL2017441B1 - Process for the preparation of a fodder compositioncomprising a fermented cereal substrate, a device forpreparing said substrate

Info

Publication number: NL2017441B1
Application number: NL2017441A
Authority: NL
Inventors: Petrus Wilhelmus Bens Rudolf; Hendrik Veldhorst Gerrit
Original assignee: De Heus Voeders B V
Priority date: 2015-09-09
Filing date: 2016-09-09
Publication date: 2017-04-03
Also published as: BE1023433B1; BE1023433A1

Abstract

The present invention relates to a process for the preparation of a fodder composition for mammals, in particular pigs, wherein the fodder composition comprises a fermented cereal substrate. Furthermore, the invention relates to a device for preparing said fermented cereal substrate. The invention also relates to said fodder composition and to said fermented cereal substrate.

Description

PROCESS FOR THE PREPARATION OF A FODDER COMPOSITION COMPRISING A FERMENTED CEREAL SUBSTRATE, A DEVICE FOR PREPARING SAID SUBSTRATE

TECHNICAL FIELD OF THE INVENTION

BACKGROUND OF THE INVENTION

Using crops as feed for livestock industry is under debate. The use of crops such as maize, wheat and soy as feed touches socio-economic and environmental issues. First, these crops are suitable for human consumption, themselves. Therewith, the use of crops as feed ingredient competes with human food supply. Second, concerns raise regarding the use of agricultural land solely for producing feed ingredients instead of crops for human food production. Third, energy conversion from crop to meat when crops are fed to e.g. pigs is rather unfavorable compared to energy conversion when crops are consumed directly by human.

An alternative to the use of crops as feed is the application of byproducts of the agro-industry and the food production industry, e.g. food waste, in the production of animal feed, or fodder. One of the various benefits of recycling byproducts such as e.g. food waste, crop residues and the like for making animal feed in livestock industry is the (re-)use of valuable ingredients and the use of the calories contained in the recyclable byproducts. Cost reduction is another benefit of recycling byproducts. Regularly, for example feeding crops to pigs is more expensive than feeding a fodder obtained by processing byproducts. Turning e.g. food waste into feed for pigs in fact turns food waste into a valuable feed co-product, useful as a constituent of a nutritious pig diet. Thus, the use of recycled byproducts for feed is an effective method of improving feed self-sufficiency and in addition also reduces the environmental burden from these byproducts.

Typical sources of food waste applicable for use in the production of fodder are products and residues of the human food, winery and brewing industries, such as for example waste from candy manufacturing, drink and food manufacturing, such as surplus bread from bakeries, whey from dairies, vegetable processing wastes and waste from (processing of) potatoes.

An important aspect of applying various sources of byproducts in production of fodder is the beneficial low pH of these food wastes. For several food wastes, the pH is typically below 4.5. This way, growth of deleterious microbes is suppressed. Animals such as pigs appreciate the taste and consumption of such low-pH feed contributes to the overall health status of the animal. Furthermore, the low pH facilitates digestion.

However, the success of the application of byproducts such as food waste in feeding livestock is challenged in several ways. First, the demand by livestock industry for byproducts is increasing, whereas the supply is decreasing, amongst others by increased efficacy of the agro-industry and the food industry. Moreover, sources of byproducts that remain available for producing fodder typically tend to have a pH which is above 4.5 which increases the risk for the growth of contaminating microbes. Overgrowth by such microbes bears a health risk for the animals fed with liquid feed compositions prepared from such byproducts, and in addition, such contaminated liquid feed composition is less tasty, thereby severely influencing the appetite of the animal. Third, a steady supply to farmers of byproducts such as food waste, having a constant quality and a constant composition, is hard to achieve due to influence of the climate, time of the year, changes in e.g. industrial food production processes, etc.

Therefore, livestock industry, and in particular pig farming industry, is in need of a more constant supply of a fodder composition comprising byproducts from agroindustry and food production industry, which fodder composition has a more constant nutritive value and quality, and which fodder composition bears a decreased risk for contamination due to growth of unwanted microbes.

SUMMARY OF THE INVENTION A first aspect of the present invention is a process for the preparation of a fodder composition for mammals, in particular pigs, comprising the steps of: a) providing an incubation vessel and loading it with water of 35°C to 39°C, culture medium ingredients and lactic acid bacteria and culturing the lactic acid bacteria in said incubation vessel, such that a starter culture of lactic acid bacteria is obtained; b) providing a fermentation vessel and rinsing it with water of 75°C tolOO°C and mixing in said vessel water with a cereal substrate; c) keeping the mixture of step b) for 30 minutes to 5 hours at 55°C to 65 °C, such that at least a partial gelatinization of the starch present in the cereal substrate takes place; d) after step c) adding cold water to the fermentation vessel, such that the cereal substrate obtained in step c) is cooled to 36°C to 40°C; e) mixing the cooled cereal substrate obtained in step d) with the starter culture of step a) and letting the lactic acid bacteria ferment said cereal substrate for 5 to 15 hours at a temperature of 30°C to 40°C, such that a fermented cereal substrate is obtained having a pH of 3 to 4; and f) mixing the fermented cereal substrate with a liquid feed composition, such that a fodder composition is obtained comprising 20 to 25% by weight dry matter, a pH of 4.5 or lower and a ratio of acetic acid to lactic acid of 1:5 to 1:40.

It has now surprisingly been found that with the process of the present invention the ratio between acetic acid and lactic acid in the fermented cereal substrate becomes very favorable regarding the taste of the fodder composition. Furthermore, it has now been found that the process according to the invention provides a fermented cereal substrate that has strong buffering capacity, keeping the pH of the fodder composition at 4.5 or lower, when mixed with liquid feed compositions with a pH of above 4.5. Moreover, with the process according to the present invention the risk of growth or overgrowth of the lactic acid bacteria by unwanted microbes, such as pathogenic bacteria is avoided.

These achievements are advantageous because now it is possible to select from a wide range of liquid feed compositions, with varying pH and differing in the amounts and types of ingredients, for the preparation of a fodder composition consistently having a pH of 4.5 or lower.

More particularly, preparation of a fodder composition having a pH of 4.5 or lower has now due to the strong buffer capacity of the fermented cereal substrate become less dependent on the source of applied liquid feed composition. Thus, a wider range of liquid feed compositions are now suitable for the preparation of a fodder composition with a desirable pH of 4.5 or lower and with a favorable acetic acid to lactic acid ratio. Due to the invention, liquid feed compositions with varying constituents or with a varying ratio of constituents from batch to batch, are well applicable for the preparation of a fodder composition comprising the fermented cereal substrate of the invention. A second aspect of the present invention is a fodder composition or fermented cereal substrate obtainable by the process of the invention. A third aspect of the present invention relates to a device for preparing a fermented cereal substrate, which device comprises: - an incubation vessel comprising means arranged for preparing a starter culture from lactic acid bacteria, water and culture medium ingredients; - a storage container for a cereal substrate; - a fermentation vessel comprising means arranged for fermenting the cereal substrate with the starter culture, wherein the fermentation vessel comprises means for supplying cold water and heated water into the fermentation vessel and wherein the incubation vessel and the storage container each comprise an outlet which is connected to an inlet of the fermentation vessel for supplying the cereal substrate and starter culture to the fermentation vessel.

DEFINITIONS

The term “cleaned” as used herein has its conventional meaning. When cleaned is used in the context of a cleaned vessel, it means that the vessel is essentially free of bacteria, fungi and other microbes. When cleaned is used in the context of cleaned cereal, it means that the cereal is treated for the purpose of obtaining cereal essentially free of contaminants such as bacteria, sand, mud, silicium oxide, mycotoxins, chaff and fungi.

The term “fermentation” as used herein has its conventional meaning and fermentation in the context of the invention refers to the culturing of a bacterium strain using culture medium as a source of nutrition, or using cereal as a source of nutrition.

The term “cereal” as used herein has its conventional meaning, and in the context of the invention cereal refers to plants that provide cereal grains and at least refers to for example wheat, barley, soy, rice, bam, oat, maize, dumm, einkom, spelt. In the context of the present invention cereal may refer to a single cereal grain, or may refer to a mixture of two or more cereal grains, in any ratio.

The term “cold water” as used herein has its conventional meaning and in the context of the invention refers to water with a temperature which is lower than 37°C, such as for example water at room temperature or water with a temperature of approximately 4°C to 24°C.

The term “controlling temperature” as used herein has its conventional meaning and in the context of the invention refers to a process in which change of temperature of water or change of temperature of the content of a fermentation vessel or an incubation vessel is measured, and the passage of heat energy into or out of the water container containing the water or into or out of the fermentation vessel or the incubation vessel is adjusted to achieve a desired average temperature.

The term “pig” as used herein has its conventional meaning and in the context of the invention refers to any pig from a piglet a few weeks of age weighing about 5 kg up to a mature pig weighing at least 120 kg, and refers also to pregnant sows and farrowing sows.

The term “fodder” as used herein has its conventional meaning and in the context of the invention refers to animal feed, more specifically feed for pigs.

The term “fodder composition” as used herein has its conventional meaning and in the context of the invention refers to any composition suitable for use as a (liquid) feed for an animal.

The term “processing” as used herein has its conventional meaning and in the context of the invention refers to the steps of a process applied to a good for the purpose of preparing the good for a certain use. In the context of the current invention, processing in ‘processing food waste’, or ‘processed food waste’, refers to making the food waste applicable for use as a liquid feed composition for, for example, pigs.

The term “byproduct” as used herein has its conventional meaning and in the context of the invention refers to any product discarded as waste in processes of agroindustry or (human) food production industry, which product, or which product after processing comprises nutritious value.

The term “food waste” as used herein has its conventional meaning and in the context of the invention refers to any edible material or residue that is generated in the production, processing, transportation, distribution, etc., or consumption of food.

The term “lactic acid bacterium” as used herein has its conventional meaning and in the context of the invention refers to any bacterium able to produce lactic acid.

In the context of the invention, lactic acid bacterium particularly refers to all genera belonging to the order Lactobacillales.

The term “gelatinization” as used herein has its conventional meaning and in the context of the invention particularly refers to gelatinization of starch. With starch gelatinization, intermolecular bonds between starch molecules are broken down under influence of the presence of heat and water. This way, starch gelatinization results in irreversibly dissolution of starch granules.

The term “liquid” in the context of “liquid food composition” and “liquid feed composition” as used herein has its conventional meaning and in the context of the invention particularly refers to an amount of water of at least 65% by weight in a composition according to the invention.

The term “sterile” as used herein has its conventional meaning and in the context of the invention particularly refers to essentially removing any form of life from any container, vessel, etc., prior to the use of said container, vessel, etc., for culturing or storage of lactic acid bacteria, cereal substrate, fodder composition, etc. In the context of the present invention, the incubation vessel and the fermentation vessel are for example sterilized by rinsing with warm water, prior to the preparation of a lactic acid bacteria starter culture in the incubation vessel and prior to the fermentation of cereal substrate using lactic acid bacteria in the fermentation vessel.

DETAILED DESCRIPTION OF THE INVENTION A first aspect of the present invention is a process for the preparation of a fodder composition for mammals, in particular pigs, comprising the steps of: a) providing an incubation vessel and loading it with water of 35°C to 39°C, culture medium ingredients and lactic acid bacteria and culturing the lactic acid bacteria in said incubation vessel, such that a starter culture of lactic acid bacteria is obtained; b) providing a fermentation vessel and rinsing it with water of 75 °C tolOO°C and mixing in said vessel water with a cereal substrate; c) keeping the mixture of step b) for 30 minutes to 5 hours at 55°C to 65 °C, such that at least a partial gelatinization of the starch present in the cereal substrate takes place; d) after step c) adding cold water to the fermentation vessel, such that the cereal substrate obtained in step c) is cooled to 36°C to 40°C; e) mixing the cooled cereal substrate obtained in step d) with the starter culture of step a) and letting the lactic acid bacteria ferment said cereal substrate for 5 to 15 hours at a temperature of 30°C to 40°C, such that a fermented cereal substrate is obtained having a pH of 3 to 4; and f) mixing the fermented cereal substrate with a liquid feed composition, such that a fodder composition is obtained comprising 20 to 25% by weight dry matter, a pH of 4.5 or lower and a ratio of acetic acid to lactic acid of 1:5 to 1:40.

In the process of the invention, lactic acid is produced by lactic acid bacteria under conditions that suppress the growth or even overgrowth of contaminating microbes; and improve the degradability of the carbohydrates in the cereals, in order to support growth of lactic acid bacteria and thereby support the lactic acid production. This way, the lactic acid is produced to a high amount and in a relative short time.

Without wishing to be bound by any theory, it is assumed that rinsing the fermentation vessel in step b) of the process according to the invention with water of 75°C tol00°C will dramatically reduce the number of unwanted microbes.

Subsequently heating of the water and the cereal substrate in the rinsed fermentation vessel, in step c) of the process according to the invention, for at least 30 minutes at at least 55°C, treats the water and cereal substrate in a way sufficient to suppress growth in step e) of the process, of any microbes that could accidentally be contaminating the water and cereal substrate. Typically, in step c) of the process according to the invention, the water and the cereal substrate are heated for 30-60 minutes at 55°C-65°C. Preferably, the water and the cereal substrate are heated for about 30 minutes at about 60°C in step c) of the process according to the invention.

This way, in step e) of the process according to the invention, predominantly, and preferably only the lactic acid bacteria in the starter culture obtained by step a) of the process are involved in the fermentation of the cereal substrate. The process according to the invention is essentially free of contaminating microbes, thereby facilitating lactic acid production and suppressing formation of unwanted contaminants such as excess acetic acid.

The fermentation of the cereal substrate by predominantly, or most preferably exclusively by lactic acid bacteria, therewith at least suppressing and most preferably excluding growth of contaminating microbes, is further facilitated by rinsing the incubation vessel of step a) of the process according to the invention with water of 75°C to 100°C, preferably at about 80°C, prior to step a) of the process. Rinsing with such warm water will essentially sterilize the incubation vessel prior to step a) of the process according to the invention. Growth of contaminating microbes is most preferably further suppressed by rinsing all surfaces which contact lactic acid bacteria in the process according to the invention, including vessels, connectors, tubings, etc., with water of 75°C to 100°C, preferably at about 80°C, prior to contacting said surfaces with the lactic acid bacteria applied in the process of the invention.

One embodiment of the invention is the process according to the invention, wherein in step e) the lactic acid bacteria ferment the cereal substrate for about 14 hours to 15 hours. It is also part of the invention that in the process according to the invention, in step e) the lactic acid bacteria ferment the cereal substrate for at least 14 hours to 24 hours, preferably between 14 hours and 24 hours. It is also part of the invention that in the process according to the invention, in step e) the lactic acid bacteria ferment the cereal substrate for about 24 hours, or for about 48 hours.

One embodiment of the invention is the process according to the invention, wherein in the fermented cereal substrate at the end of step e) the ratio between acetic acid and lactic acid ranges from 1:7 to 1:13.

Olstorpe et al. (Journal of Applied Microbiology, Volume 108, 2010, pp.129-138) incubated a rehydrated lyophilized lactic acid bacteria starter culture with various cereal feed mixtures, at 20°C. Fermentation lasted for five days and longer. Bacteria and yeast already present in the cereal feed mixture at the start of the incubation grew during the incubation and were abundantly present after the incubation with the starter culture.

International patent application WO 2008/006382 describes a process for the provision of a fermented feed product. In the process, a (by-)product from e.g. an industrial process, is first fermented by addition of lactic acid bacteria to the (byproduct. Subsequently, the fermented (by-)product comprising lactic acid bacteria is applied to a feed product, for fermentation of the feed product.

One embodiment of the invention is the process according to the invention, wherein in step d) the cold water is water with a temperature which is lower than 37°C, preferably water at room temperature, more preferably water with a temperature of between 4°C and 24°C, most preferably about 8°C. One embodiment of the invention is the process according to the invention, wherein in step d) the cold water is water with a temperature of about 8°C.

In one embodiment of the invention, a so called cleaned cereal composition is applied as a cereal substrate in step b) of the process. Applying a cleaned cereal composition has the benefit of even further directing the fermentation of cereal substrate in the process according to the invention towards lactic acid producing activity of lactic acid bacteria only. Thereby, (chance of) growth of any contaminating microbe occasionally present in the fermentation vessel during step e) of the process is further suppressed or even excluded. This way, batch-to-batch stability of the fodder composition obtained in step f) of the process according to the invention is improved due to the essentially mono-culturing of lactic acid bacteria, and overall quality of the fermented cereal substrate is improved due to a more constant and high content of lactic acid, and a beneficial acetic acid to lactic acid ratio. Of course, if cereal substrate is essentially free of microbes, applying cleaned cereal composition as the cereal substrate in step b) of the process of the invention, has essentially no effect on the culturing of lactic acid bacteria in step e) of the process of the invention, when compared to applying said cereal substrate which is essentially free of microbes and that is not cleaned before mixing with water in step b) of the process of the invention, according to the invention. In particular, this is true when the cereal substrate is essentially free of microbes that potentially grow in e.g. step e) of the process of the invention, and/or that have the potential to overgrowth the lactic acid bacteria. Thus, applyi ng cereal substrate which is essentially free of contaminants such as bacteria, sand, mud, silicium oxide, mycotoxins, chaff and fungi in step b) of the process of the invention, provides for essentially the same fermented cereal substrate in step e) of the process of the invention, compared to when said cereal substrate is cleaned before application in the method of the invention.

One embodiment of the invention is the process according to the invention, wherein the cereal substrate provided in step b) is cleaned cereal composition, which is cereal substrate that is treated for the purpose of obtaining cereal essentially free of contaminants. The cleaned cereal composition is a cereal substrate that is treated for the purpose of obtaining cereal essentially free of contaminants such as bacteria, sand, mud, silicium oxide, mycotoxins, chaff and fungi.

To further diminish the probability of growth of contaminating microbes other than the lactic acid bacteria according to the invention, in one embodiment of the invention the cleaned cereal composition is a cereal composition that is essentially freed from e.g. bacteria, sand, mud, silicium oxide (silica oxide), mycotoxins, chaff and fungi.

According to the invention, the cleaned cereal composition applied in the process of the invention consists of a single type of cereal, or comprises two or more types of cereal. Typically, the cleaned cereal composition according to the invention comprises at least barley, wheat, com, rice, wheat bran, and their (by)products, and any combination thereof. According to the invention, the cereal substrate applied in the process of the invention consists of a single type of cereal, or comprises two or more types of cereal. Typically, the cereal substrate according to the invention comprises at least barley, wheat, com, rice, wheat bran, and their (byproducts, and any combination thereof. In one embodiment, the cleaned cereal composition of the invention preferably further comprises one or more of the additives selected from vitamins, minerals, acids, proteins and lactoses. In one embodiment, the cereal substrate of the invention preferably further comprises one or more of the additives selected from vitamins, minerals, acids, proteins and lactoses. Alternatively, or additively, one or more of the additives selected from vitamins, minerals, acids, proteins are added to the fodder composition obtained in step I) of the process according to the invention. Of course, any other food additive is suitably added to the fodder composition if desired, as part of the invention.

In one embodiment of the invention, a cleaned cereal composition according to the invention is provided as crushed cereal granules. Such crushed cereal granules are obtained by crushing of milled cereal that was previously pelleted at a temperature of about 60°C to 80°C, preferably at 65°C to 80°C. Pelleting at such a temperature contributes to the sterilization of the cereal, thereby suppressing or even prohibiting the growth of any microbe accidentally contaminating the cereal during the fermentation in step e) of the process according to the invention. Furthermore, pelleting at a temperature of about 60°C to 80°C, preferably at 65°C or higher facilitates at least a partial gelatinization of the starch present in the cereal substrate. Without wishing to be bound by any theory, it is assumed that formation of lactic acid from gelatinized starch by lactic acid bacteria is more sufficient compared to fermentation of non-gelatinized starch in the cereal granules.

One embodiment of the invention is the process for the preparation of a fodder composition for mammals, in particular pigs, according to the invention, comprising the steps of: a) providing an incubation vessel and loading it with water of 35°C to 39°C, culture medium ingredients and lactic acid bacteria and culturing the lactic acid bacteria in said incubation vessel, such that a starter culture of lactic acid bacteria is obtained; b) providing a fermentation vessel and rinsing it with water of 75°C tolOO°C and mixing in said vessel water with a cereal substrate; c) keeping the mixture of step b) for 30 minutes to 5 hours at 55°C to 65 °C, such that at least a partial gelatinization of the starch present in the cereal substrate takes place; d) after step c) adding cold water to the fermentation vessel, such that the cereal substrate obtained in step c) is cooled to 36°C to 40°C; e) mixing the cooled cereal substrate obtained in step d) with the starter culture of step a) and letting the lactic acid bacteria ferment said cereal substrate for 5 to 15 hours at a temperature of 30°C to 40°C, such that a fermented cereal substrate is obtained having a pH of 3 to 4; and f) mixing the fermented cereal substrate with a liquid feed composition, such that a fodder composition is obtained comprising 20 to 25% by weight dry matter, a pH of 4.5 or lower and a ratio of acetic acid to lactic acid of 1:5 to 1:40, wherein the cereal substrate in step b) is a cleaned cereal composition.

One embodiment of the invention is the process for the preparation of a fodder composition for mammals, in particular pigs, according to the invention, wherein the cereal substrate in step b) is a cleaned cereal composition consisting of crushed cereal granules.

One embodiment of the invention is the process for the preparation of a fodder composition for mammals, in particular pigs, according to the invention, wherein the cereal substrate in step b) is a cleaned cereal composition consisting of crushed cereal granules which are obtained by crushing of milled cereal that was previously pelleted at a temperature of about 60°C to 80°C, preferably at 65°C to 80°C.

It has now surprisingly been found that the ratio between acetic acid and lactic acid in the fermented cereal substrate is very favorable regarding the taste of the fodder composition obtained by the process of the invention. Furthermore, it has now surprisingly been found that the process according to the invention provides a fermented cereal substrate that has strong buffering capacity, keeping the pH of the fodder composition at 4.5 or lower, when mixed with liquid feed compositions with a pH of above 4.5.

These two achievements are advantageous because now it is possible to select from a wide range of liquid feed compositions, with varying pH and differing in the amounts and types of ingredients, for the preparation of a fodder composition consistently having a pH of 4.5 or lower.

More particularly, preparation of a fodder composition having a pH of 4.5 or lower has now become less dependent on the source of applied liquid feed composition. Thus, a wider range of liquid feed compositions are now suitable for the preparation of a fodder composition with a desirable pH of 4.5 or lower and with a favorable acetic acid to lactic acid ratio. Due to the invention, liquid feed compositions with varying constituents or with a varying ratio of constituents from batch to batch, are all equally well applicable for the preparation of a fodder composition comprising the fermented cereal substrate of the invention.

Further improved batch-to-batch stability of the fodder composition prepared by the process according to the invention is achieved by applying a solid composition of lactic acid bacteria and culture medium ingredients, preferably a solid freeze dried composition, in step a) of the process according to the invention. According to the invention, in such a solid composition the type and amounts of culture medium ingredients are well-balanced for preparing the starter culture in step a) of the process according to the invention. Applying such an optimized solid composition of lactic acid bacteria and culture medium ingredients, preferably a solid freeze dried composition, provides a starter culture of constant quality comprising about the same number of lactic acid bacteria from batch to batch in about the same culturing time.

One of the various benefits of the process according to the invention is the acceleration of the fermentation of cereals in step e) of the process, when compared to conventional fermentation processes. By reducing the preparation time of the fodder composition by accelerating the fermentation step e) of the process according to the invention, it has now become possible to prepare the fodder composition at the day the fodder composition is fed, e.g. to pigs. An important drawback of conventionally prepared fodder compositions is that they require an acidification step once kept in a feeding system comprising e.g. lines filled with the fodder composition. This, in order to suppress growth of undesired microbes in the conventionally prepared fodder composition in e.g. the lines during the period in between feedings of pigs. Due to the various benefits of the current invention, this undesirable acidification step with the fodder composition in between feedings is not required anymore, since the pH of the fodder composition according to the invention is below 4.5, thereby beneficially hampering growth of undesired microbes. Preferably, the duration of the process according to the invention is about 12-16 hours, most preferably about 14 hours. Avoiding storage of fodder composition prevents growth of e.g. (pathogenic) yeast and molts in the fodder composition, thereby preventing e.g. degradation of lactic acid, an increase in acetic acid content and/or an increase of the pH.

In conventional fermentation processes, typically a bacterial starter culture or a yeast starter culture is applied which has been prepared several hours to days before the start of the fermentation step, and which is prepared in a separate process, most often at a separate location than the pig farm, requiring transportation and (prolonged) storage of the bacterial starter culture. By preparing a fresh starter culture of lactic acid bacteria in step a) of the process according to the invention, just prior to mixing the freshly obtained starter culture with the cereal substrate in step e) of the process according to the invention, subsequent fermentation of the cereal substrate is accelerated. Fermentation of the cereal substrate by the lactic acid bacteria starter culture is further accelerated and facilitated by including an accelerator in the starter culture at the start of the culturing. Said accelerator improves growth of the lactic acid bacteria in the starter culture, and said accelerator comprises flour of one or more cereals. Thus, according to the invention, in step a) the lactic acid bacteria are cultured for about 1 to 10 hours, preferably for about 4 to 7 hours, more preferably for about 5 to 6 hours, for the preparation of a freshly derived starter culture. Also according to the invention, in step a) about 1.5E11 to 2.5E11 lactic acid bacteria, preferably about 2E11 lactic acid bacteria, are mixed with the cereal substrate in the incubation vessel. Typically, in step a) the incubation vessel is loaded with about 15 liter water and about 4 kg of lactic acid bacteria and culture medium ingredients comprising the accelerator. The lactic acid bacteria that is subsequently mixed in step e) with the cereal substrate in the fermentation vessel is the freshly obtained starter culture obtained with step a) of the process according to the invention. Typically, the starter culture obtained with step a) is added to about 1.200 kg cereal substrate in step e) of the process according to the invention.

Furthermore, according to the invention, in step e) of the process according to the invention the cereal substrate is fermented for about 5 to 24 hours, preferably for about 13 to 17 hours, most preferably for about 15 hours. Typically, in the process according to the invention, in step a) the lactic acid bacteria are cultured for about 5 to 6 hours, for the preparation of a freshly derived starter culture, and in step e) the cereal substrate is fermented for about 15 hours. Typically, in the process according to the invention, the fodder composition in step f) is provided in about 20 hours from the start of step a) of the process.

Genera that comprise the lactic acid bacteria are Lactobacillus, Leuconostoc, Pediococcus, Lactococcus, and Streptococcus, Aerococcus, Camobacterium, Enterococcus, Oenococcus, Teragenococcus, Vagococcus, and Weisella; these genera belong to the order Lactobacillales. Lactic acid bacteria suitable for application in the process for the preparation of a fodder composition according to the invention are numerous.

Specially suitable lactic acid bacteria for the purpose of the invention are lactic acid bacteria of the genus Enterococcus, Lactobacillus, Pediococcus or Lactococcus, or combinations thereof. Typically, one or more lactic acid bacteria are selected from the group consisting of Enterococcus spp., Lactobacillus spp., Lactococcus spp., Pediococcus spp., Enterococcus faecium, Lactobacillus rhamnosus, Lactobacillus paracasei, Lactobacillus plantarum, Pediococcus acidililactili, Pediococcus pentosaceus, Lactobacillales, Lactobacillus spp., Pediococcus spp., Enterococcus spp., Lactococcus spp., Pediococcus pentosaceus, Pendiococcus acidilactici, Lactobacillus plantarum, Lactobacillus rhamnosus, Enterococcus faecium, Enterococcus faecium, Lactobacillus rhamnosus, Enterococcus faeciumMCIMB30122, Lactobacillus rhamnosus NCIMB30121, Pediococcus pentosaceus HTS (LMG P-22549), Pendiococcus acidilactici NCIMB 30086, Lactobacillus plantarum LSI (NCIMB 30083).

Preferably, in the process according to the invention, the lactic acid bacteria are chosen from the group consisting of Lactobacillus paracasei, Lactobacillus plantarum, Pediococcus pentosaceus, Pediococcus acidilactici and Lactobacillus rhamnosus.

One embodiment of the invention is the process according to the invention, wherein the fermented cereal substrate provided in step e) of the process has a pH of between about 3.3 and 4.0. Preferably, the pH of the fermented cereal substrate is about 3.4, 3.5, 3.6, 3.7, 3.8 or 3.9. One embodiment of the invention is the process according to the invention, wherein the fermented cereal substrate provided in step e) of the process has a pH of between 3.5 and 3.8. A second aspect of the present invention relates to a fodder composition or fermented cereal substrate obtainable by the process of the invention.

One aspect of the present invention relates to a fodder composition obtainable by the process of the invention.

One aspect of the present invention relates to a fermented cereal substrate obtainable by the process of the invention. A fodder composition obtainable by the process of the invention differs from known fodder compositions in that it has an improved batch-to-batch pH stability in that the pH of each subsequently prepared fodder composition is about the same as the pH of the preceding fodder composition obtained by the process of the invention.

About the same pH in the context of the invention has its conventional meaning and in the context of the invention refers to a pH plus or minus 0.7, preferably plus or minus 0.5, more preferably plus or minus 0.2. As said before, the pH of a fodder composition obtained by the process of the invention is 4.5 or less. Preferably, the pH of a fodder composition obtained by the process of the invention ranges from pH 4 to pH 4.5, more preferably the pH of the fodder composition is about pH 4.25. A fodder composition with a pH above 4 is particularly tasty for the pig, whereas the pig’s appetite is hampered when fodder composition with a pH below 4 is fed. In a fodder composition with a pH below 4.5, undesired growth of occasionally present undesired microbes is suppressed. Therewith, quality and safety of the fodder composition according to the invention is better secured.

One embodiment of the invention is the fodder composition according to the invention, wherein the pH of the fodder composition is 4.5 or lower, preferably between 4.0 and 4.5, more preferably about 4.25.

Furthermore, a fodder composition obtained by the process of the invention differs from known fodder compositions in that it has an improved acetic acid to lactic acid ratio. According to a preferred embodiment of the invention, the ratio between acetic acid and lactic acid ranges from 1:5 to 1:40, preferably said ratio ranges from 1:7 to 1:30, preferably 1:7 to 1:20, more preferably 1:9 to 1:15. Preferably, the ratio between acetic acid and lactic acid ranges from 1:10 to 1:12. One embodiment of the invention is the fodder composition according to the invention, wherein the ratio between acetic acid and lactic acid ranges from 1:7 to 1:13.

Such acetic acid to lactic acid ratios in the fodder composition according to the invention improve the quality of the fodder composition in that the tastefulness is improved thereby stimulating appetite of the mammals, in particular pigs, fed with the fodder composition. The beneficial acetic acid to lactic acid ratio according to the invention is achieved by culturing lactic acid bacteria under the more sterile conditions of the process for the preparation of a fodder composition according to the invention. Growth of acetic acid producing microbes such as e.g. yeast, moulds, fungi is suppressed and at least outcompeted by the growth of the lactic acid bacteria cultured in step a) of the process according to the invention. Production of lactic acid is improved in step e) of the process according to the invention, by applying freshly cultured starter culture of lactic acid bacteria in a sterile mixture of water and cereal substrate, preferably a cleaned cereal composition.

The fodder composition according to the invention typically has a dry matter content of about 20-35 weight %, preferably about 21-27 weight %, more preferably about 24 weight %, in which said dry matter comprises 15-60 weight % fermented cereal substrate on a dry matter basis, preferably about 20-50 weight %, more preferably about 30 weight % on a dry matter basis. The fodder composition according to the invention typically comprises 18-30% by weight dry matter, preferably 21 -27%, more preferably 23-25% by weight dry matter, and most preferably about 24% by weight dry matter.

One embodiment of the invention is the process according to the invention, wherein the fodder composition in step f) typically has a dry matter content of about 20-35 weight %, preferably about 21-27 weight %, more preferably about 24 weight %.

One embodiment of the invention is the process according to the invention, wherein the fodder composition in step f) typically has a dry matter content of 18-30 weight %, preferably about 21-27 weight %, more preferably about 23-25 weight %, and most preferably about 24 weight %.

The buffer strength of the fermented cereal substrate according to the invention, as well as the pH of said substrate and the nutritious value of said substrate, make the fermented cereal substrate particularly suitable for the preparation of the fodder composition according to the invention. As said before, batch to batch variation in the liquid feed composition, which is mixed with the fermented cereal substrate in step f) of the process according to the invention, does not hamper the preparation of the fodder composition according to the invention. Variation in pH of the liquid feed composition is tolerated in the process according to the invention due to the buffer strength of the fermented cereal substrate, providing fodder composition with a constant pH at or below 4.5. By adjusting the amount of fermented cereal substrate that is mixed with the liquid feed composition, the desired pH of about 4.25 is achieved. Similarly, the nutritious value of the fodder composition according to the invention is adjusted to a desired level, by adjusting the amount of fermented cereal substrate that is mixed with a selected liquid feed composition. This way, the fodder composition of the invention is easily adjusted for optimized consumption by the target mammal fed with the fodder composition. For example, the amount of fermented cereal substrate mixed with a selected liquid feed composition is chosen in order to obtain a fodder composition according to the invention that has a nutritious value optimized for e.g. sows (during gestation), piglets, mature pigs. Similarly, due to the various beneficial aspects of the fermented cereal substrate of the invention, the dry matter content of the fodder composition according to the invention is now easily adjusted towards a selected value, even with varying dry matter contents of subsequent batches of a liquid feed composition.

In the process according to the invention, preferably, in step a) on a weight basis 1 part of culture medium ingredients and lactic acid bacterium and accelerator, comprising about 1.5E11 to 2.5E11 lactic acid bacteria, and about 3,75 parts of water are loaded into the incubation vessel, and wherein in step e) on said weight basis about 3 parts water and about 2 parts cereal substrate are loaded into the fermentation vessel, and wherein in step 1) prior to mixing the fermented cereal substrate with a liquid feed composition, on said weight basis about 3 parts cold water is loaded into the fermentation vessel. Typically, about 2-5 kg, preferably about 4 kg of solid culture medium ingredients and lactic acid bacterium and about 10-20 kg, preferably about 15 kg of water are loaded into the incubation vessel in step a) of the process according to the invention. Typically, about 1200-2000 kg water and about 800-1300 cereal substrate are loaded into the fermentation vessel in step e) of the process according to the invention. In a preferred embodiment of the invention, about 4 kg of culture medium ingredients and lactic acid bacterium, and about 15 kg of water are loaded into the incubation vessel in step a) of the process according to the invention; in step e) about 1640 kg warm water and about 1030 kg cereal substrate are loaded into the fermentation vessel; and in step 1), prior to mixing the fermented cereal substrate with a liquid feed composition, about 1560 kg cold water is loaded into the fermentation vessel.

Of course, amounts of warm water, cereal substrate and cold water are adjusted within certain limits to a ratio that provides the fermented cereal substrate with a desired content of dry matter for the purpose at hand.

The fodder composition obtainable by the process according to the present invention is thus suitable for feeding mammals, and preferably the fodder composition obtainable by the process of the invention is a pig feed. A third aspect of the present invention relates to a device for preparing a fermented cereal substrate, which device comprises: - an incubation vessel comprising means arranged for preparing a starter culture from lactic acid bacteria, water and culture medium ingredients; - a storage container for a cereal substrate; - a fermentation vessel comprising means arranged for fermenting the cereal substrate with the starter culture, wherein the fermentation vessel comprises means for supplying cold water and heated water into the fermentation vessel and wherein the incubation vessel and the storage container each comprise an outlet which is connected to an inlet of the fermentation vessel for supplying the cereal substrate and starter culture to the fermentation vessel.

Such a device for preparing a fermented cereal substrate according to the invention differs from current devices in that the incubation vessel is an integrated part of the device further comprising the storage container and the fermentation vessel. With this configuration of the device according to the invention, the incubation vessel is very suitable for preparing a lactic acid bacteria starter culture shortly, that is to say less than 6 hours, preferably about 3-5 hours, more preferably about 4 hour, before the start of the fermentation of a cereal substrate in the fermentation vessel using a lactic acid bacteria starter culture. Furthermore, with such configuration of the device according to the invention, the incubation vessel and the fermentation vessel are easily rinsed with heated water and thereby sterilized, before lactic acid bacteria starter culture is prepared in the incubation vessel and before cereal substrate is fermented by lactic acid bacteria in the fermentation vessel. Thus, the device according to the invention now makes it possible to prepare a fermented cereal substrate under sterile conditions. The device for preparing a fermented cereal substrate according to the invention allows for improved controlling of the preparation of the fodder composition according to the invention. Allowing preparation of a lactic acid bacteria starter culture shortly before fermentation of cereal substrate, as well as providing means for preparing a fermented cereal substrate according to the invention under essentially sterile conditions, significantly contributes to the desired preparation of a well-defined fodder composition according to the invention with a high batch-to-batch stability regarding pH and nutritious value.

In one embodiment, the device according to the invention further comprises a container for storage of cold water and/or a container for storage of heated water, provided with an outlet connected to the means for supplying cold water and heated water into the fermentation vessel. Of course, according to the invention, preferably the container for storage of heated water further comprises means for heating the water.

Preferably, the device according to invention comprises a weighing unit for weighing the content of the incubation vessel, the cold water and the heated water, the content of the storage container for cereal and the content of the fermentation vessel.

Preferably, the device according to the invention also comprises a means for controlling temperature in the incubation vessel and in the fermentation vessel.

In one embodiment of the invention, the device according to the invention further comprises means for supplying heated water comprising a second outlet connected to an inlet of the incubation vessel, for supplying heated water to said incubation vessel. This way, the device according to the invention is provided with means to rinse the incubation vessel with heated water prior to step a) of the process according to the invention. The incubation vessel is essentially cleared from any (contaminating) microbes that could be present in said vessel, before loading the vessel with water, culture medium ingredients and lactic acid bacteria and culturing the lactic acid bacteria in said incubation vessel.

At the end of the process for the preparation of the fodder composition according to the invention, the fodder composition is either fed directly to the mammals, e.g. pigs, or is completely or in part stored before being fed. For practical reasons, in one embodiment of the invention, fodder composition prepared with the device according to the invention is thus stored for a short time, e.g. 30 minutes to 1-3 hours, before being fed to e.g. pigs. Thus, it is part of the invention that the device according to the invention comprises a second storage container, connected to an outlet of the fermentation vessel, which second storage container is arranged for storing fodder composition according to the invention. Storing the fodder composition in said storage container allows for the start of a new process for the preparation of the fodder composition according to the invention, using the device according to the invention.

Additively or to the alternative, at the end of step e) of the process for the preparation of the fodder composition according to the invention, the fermented cereal substrate is completely or in part stored before subjected to step f) of the process according to the invention. For practical reasons, in one embodiment of the invention, fermented cereal substrate prepared in step e) with the device according to the invention is thus stored for a short time, e.g. 30 minutes to 1-3 hours, before being mixed with a liquid feed composition in step f) in the process according to the invention. Thus, it is part of the invention that the device according to the invention comprises an additional storage container, connected to an outlet of the fermentation vessel, which additional storage container is arranged for storing fermented cereal substrate according to the invention. Storing the fermented cereal substrate in said storage container allows for the start of a new process for the preparation of the fodder composition according to the invention, using the device according to the invention.

In a preferred embodiment of the invention, the fermented cereal substrate of the invention is mixed with a liquid feed composition in step f) of the process according to the invention, shortly, e.g. 1-30 minutes, before the fodder composition obtained by said mixing is fed to e.g. pigs.

Thus, it is part of the invention that the device according to the invention comprises a second storage container, connected to an outlet of the fermentation vessel, which second storage container is arranged for storing a liquid feed composition. This way, the device is optimally suitable for the preparation of freshly mixed fermented cereal substrate and liquid feed composition, thereby further diminishing the risk for undesired growth of microbes in the fodder composition of the invention.

The invention is, without limitation, further specified by the Examples provided below.

EXAMPLE

General experimental method for preparing fermented pelletized cereals and cereal (by)products

Step 1 Preparation of lactobacillus culture in a separate container.

Dry Starter culture of lactic acid bacterium lactobacillus (stock piled in 25 kg bags (1)) is stored in a separate container (2) and dosed in the lactobacillus preculture tank (4) with a jackscrew (3) (See Figure). Weighing of the starter culture (1) is with a load cell. For culturing lactobacillus 1 kg of Optistart starter culture (lactobacillus culture and growth medium) is brought in 2 liter of water of 37,5 °C. The mixture of starter culture and water is incubated for 4-5 hours under interval, gentle stirring. Temperature is controlled and kept between 36-39 °C.

Step 2 Preparing pelletized cereals and cereal(by)products (Optimix).

The mixing tank (6) is first flushed with hot water (>70 C°) (7b), which enters the mixing tank (6) via an inlet (7a) from a hot watertank (7). The hot water is kept in the mixing tank (6) after flushing. The pelletized cereals and cereal(by)products (Optimix) (8) is dosed from the Optimix container (9) via a jackscrew (10) in the hot water up to a mixture with 32-35% by weight dry matter originating from the Optimix. The hot water-Optimix mixture is kept at a temperature of above approximately 60 °C for 30 minutes, to sterilize the hot water-Optimix mixture. Cold water (1 lb) is added from a cold watertank (11) via an inlet (1 la) to the sterilized hot water-Optimix mixture up to a temperature of the mixture is achieved of 37-39 °C. The dry matter content of the water-Optimix mixture is brought to approximately 25% by weight. The water-Optimix mixture is continuously mixed with mixer (12) during addition of cold water in order to homogenize the water-Optimix mixture.

Step 3 Starting fermentation for preparing a fermented cereal substrate

The pre-prepared lactobacillus culture is added to the water-Optimix mixture in the mixing tank (6) via inlet (4a) to start the fermentation of the water-Optimix mixture, for preparation of fermented pelletized cereals and cereal (by)producrs, “Combiferm” (13).

Preferably, the lactobacillus culture is entering the mixing tank (6) using free flow, under continuous stirring.

The mixture of water-Optimix with lactobacillus culture is either kept in the mixing tank (6) during fermentation to Combiferm, or this mixture is transported to a fermentation silo (not shown) using a pump (14) for subsequent fermentation to Combiferm. The water-Optimix with lactobacillus culture ferments for at least 14-24 hours, before Combiferm is formed and further mixed with other (byproducts, and fed to the pigs. When Combiferm is produced in the mixing tank (6), after fermentation the Combiferm is pumped to a second storage container (not shown), connected to the outlet (14) of the mixing tank (6) (fermentation vessel), which second storage container is arranged for storing a liquid feed composition. The pH of the fermented mixture Combiferm is 3.5-3.8. The ratio Lactic Acid to Acetic Acid in the Combiferm (i.e. pelletized cereals and cereal (byproducts, Optimix, after fermentation) is approximately 10 : 1.

Experimental data

For 2650 pigs, daily doses of Combiferm were prepared. The pigs were fed 1.95 kg feed per day, comprising 20% by weight Combiferm based on the dry matter of the feed. The 2650 pigs were fed 4547 kg dry matter of total feed per day, comprising the 20% by weight Combifirm based on the dry matter. In total, 4230 kg Combiferm was fed to the pigs per day.

Combiferm was prepared with a final dry matter content of 22% after fermentation of the Optimix pelletized cereals and cereal (by)products with the lactobacillus preculture. The Optimix had a dry matter content of 88% by weight.

In Step 2 of the production of Combiferm (see above and Figure), First, 1641 kg hot water at 88°C is brought in the mixing tank (6), for sterilization purposes. Then, 1034 kg of cereals and cereal (byproducts Optimix at 10°C is brought into the mixing tank (6) and mixed with the hot water. These 1034 kg Optimix comprised 909 kg dry matter (88% by weight). The temperature after mixing is 58°C. Water at 88°C is added in order to keep the water-Optimix mixture at a temperature of above approximately 60°C. During the sterilization step, the dry matter content was 34% by weight. After sterilization, the temperature is brought to 39.6°C by adding 1555 kg cold water at 8°C, while mixing. The start of the fermentation process upon addition under mixing of the lactobacillus preculture was approximately 37°C. Fermentation was prolonged for up to 48 hours. At time intervals 24 h and 48 h after the start of the fermentation, the ratio between acetic acid and lactic acid was determined (Table).

Five of these Optimix batches were prepared separately at different days, according to the protocol above.

Description of the Figure

Figure: Device for preparing a fermented cereal substrate, which device comprises: - an incubation vessel (preculture tank (4)) comprising means arranged for preparing a starter culture from lactic acid bacteria (container (2), jackscrew (3), mixer (5)), water and culture medium ingredients (1); - a storage container for a cereal substrate (9); - a fermentation vessel (mixing tank (6)) comprising means (mixer (12)) arranged for fermenting the cereal substrate with the starter culture, wherein the fermentation vessel comprises means (cold water tank (11), inlet (11a); hot water tank (7), inlet (7a)) for supplying cold water (1 lb) and heated water (hot water (7b)) into the fermentation vessel and wherein the incubation vessel (4) and the storage container (9) each comprise an outlet which is connected to an inlet of the fermentation vessel (inlet (4a), jackscrew (10)) for supplying the cereal substrate (8) and starter culture to the fermentation vessel (6).

Claims

AMENDED CONCLUSIONS

A method for the preparation of a feed composition for mammals, in particular pigs, comprising the steps of: a) providing an incubator and loading it with water from 35 ° C to 39 ° C, culture medium ingredients and lactic acid bacteria and culturing the lactic acid bacteria in the relevant incubation vessel, so that a starter culture of lactic acid bacteria is obtained; b) providing a fermentation vessel and rinsing it with water from 75 ° C to 100 ° C and mixing water and a grain substrate in the vessel; c) keeping the mixture from step b) at 55 to 65 ° C for 30 minutes to 5 hours, so that at least a partial gelatinization of the starch present in the cereal substrate takes place; d) after step c) adding cold water with a temperature lower than 37 ° C to the fermentation vessel, so that the grain substrate obtained in step c) is cooled to 36 ° C to 40 ° C; e) mixing the cooled cereal substrate obtained in step d) with the starting culture of step a) and allowing the lactic acid bacteria to ferment the respective cereal substrate for 5 to 15 hours at a temperature of 30 ° C to 40 ° C, so that a fermented grain substrate is obtained with a pH of 3 to 4; and f) mixing the fermented grain substrate with a liquid feed composition to obtain a feed composition comprising 20 to 25 weight percent dry matter, a pH of 4.5 or lower and a ratio of acetic acid to lactic acid from 1: 5 to 1:40, wherein the cereal substrate is a cleaned grain composition, wherein the grain is substantially free of contaminants such as bacteria, sand, sludge, silica, mycotoxins, chaff, and fungi.

A method according to claim 1, wherein prior to step a), the respective incubation vessel is flushed with water from 75 ° C to 100 ° C, preferably at about 80 ° C.

The method according to claims 1 or 2, wherein the cleaned cereal composition comprises barley, wheat, maize, rice, bran, and their (by) products, and any combination thereof.

The method of any one of the preceding claims, wherein the cleaned cereal composition is provided as crumbled cereal grains.

A method according to any one of the preceding claims, wherein in step a) the lactic acid bacteria and the culture medium ingredients are provided as a solid composition, preferably a freeze-dried composition.

The method according to any of the preceding claims, wherein in step e) the grain substrate is fermented for 5 to 24 hours, preferably for about 13 to 17 hours.

A method according to any one of the preceding claims, wherein the lactic acid bacteria are selected from the group consisting of Lactobacillus paracasei, Lactobacillus plantarum, Pediococcus pentosaceus, Pediococcus acidilactici and Lactobacillus rhamnosus.

A feed composition obtainable by the method according to any one of claims 1-7.

A fermented grain substrate obtainable by the method according to any of claims 1-7.

The feed composition of claim 8, wherein the pH of the feed composition is in the range of 4 to 4.5, more preferably the pH is about 4.25.

A feed composition according to claim 8 or 10, wherein the ratio between acetic acid and lactic acid is in the range of 1: 7 to 1:30, preferably from 1: 7 to 1:20, more preferably from 1: 9 to 1: 15.

A feed composition according to any one of claims 8, 10, 11, wherein the feed composition comprises 21-25 percent by weight of dry matter, preferably 23-25% by weight of dry matter.

A device for preparing a fermented grain substrate, which device comprises: an incubation vessel comprising means adapted to prepare a starter culture of lactic acid bacteria, water and culture medium ingredients; a storage container for a grain substrate; a fermentation vessel comprising means adapted to ferment the cereal substrate with the starter culture, wherein the fermentation vessel comprises means for supplying cold water and heated water into the fermentation vessel and wherein the incubation vessel and the storage container each comprise an outlet which is coupled to a inlet of the fermentation vessel to feed the grain substrate and the starter culture to the fermentation vessel.

Device as claimed in claim 13, wherein the device comprises a second storage container, coupled to an outlet of the fermentation vessel, which second storage container is adapted for storage of a liquid feed composition.