PRESERVATION OF WATER-SOLUBLE VITAMINS

Abstract

The present invention relates to a method including heat treatment of a composition including chitin and water-soluble vitamins and/or derivatives thereof. The invention also relates to a granule which can be obtained by the method according to the invention, a granule comprising chitin and water-soluble vitamins and/or derivatives thereof, and the use of said granules in human food or animal feed, more particularly in fish feed. Finally, the invention relates to the use of chitin to protect water-soluble vitamins during heat treatment.

Claims

1. Process comprising a heat treatment of a composition at a temperature greater than or equal to 90 C., in which the composition comprises at least 0.8% by weight chitin and at least 0.005% by weight water-soluble vitamins and/or derivatives thereof, relative to the total weight of the composition.

2. Process according to claim 1, in which the composition comprises at least 0.05% by weight group B and group C vitamins and/or derivatives thereof, relative to the total weight of the composition.

3. Process according to claim 1, in which the composition comprises at least 0.004% by weight vitamins B6 and/or B9 and/or derivatives thereof, relative to the total weight of the composition.

4. Process according to claim 1, in which the composition comprises at least 1.5% by weight chitin relative to the total weight of the composition.

5. Process according to claim 1, in which the temperature is greater than or equal to 100 C.

6. Process according to claim 1, in which the heat treatment is carried out under pressure.

7. Process according to claim 1, in which the process is a granulation.

8. Process according to claim 1, in which the process is an extrusion.

9. Granule capable of being obtained by a process comprising a heat treatment of a composition at a temperature greater than or equal to 90 C., in which the composition comprises at least 0.8% by weight chitin and at least 0.005% by weight water-soluble vitamins and/or derivatives thereof, relative to the total weight of the composition, wherein said process is an extrusion in combination with a granulation.

10. Granule comprising at least 0.6% chitin and at least 0.004% by weight water-soluble vitamins, relative to the total weight of the granule and having an apparent density after drying comprised between 400 and 650 g/L.

11. Use of chitin for protecting water-soluble vitamins during a heat treatment at a temperature greater than or equal to 90 C.

12. Process according to claim 1, in which the chitin results from the introduction of an insect, crustacean, squid and/or fungi meal.

13. Use of a granule according to claim 9, in human food or animal feed.

14. Granule according to claim 10, in which the chitin results from the introduction of an insect, crustacean, squid, and/or fungi meal.

15. Use according to claim 11, in which the chitin results from the introduction of an insect, crustacean, squid, and/or fungi meal.

Description

[0121] The invention will be better understood in the light of the following examples, given by way of illustration, with reference to:

[0122] FIG. 1, which comprises three diagrams representing the quantities of vitamins A (FIG. 1A), B6 (FIG. 1B) and B9 (FIG. 1C) in granules obtained according to the process according to the invention, and in granules obtained according to a comparative process;

[0123] FIG. 2, which is a diagram representing the percentage loss of vitamin A, B6 and B9 with the process according to the invention and with the comparative process;

[0124] FIG. 3, which is a diagram representing the mass density of granules obtained according to the process according to the invention, and granules obtained according to a comparative process.

EXAMPLE 1

Process According to the Invention and Comparative Process

1. Material and Methods

1.1. Material

[0125] Ingredients for Preparing the Compositions to be Granulated

[0126] Insect Meal

[0127] A mechanically defatted insect meal is obtained by treatment of Tenebrio molitor larvae. The composition of this meal is presented in Table 1 below.

TABLE-US-00001 TABLE 1 Composition of the insect meal used in Example 1 Unit Insect meal Moisture %* 5.3 Protein %* 67.1 Fat %* 13.6 Fibre %* 1.6 Ash %* 3.2 Chitin %* 8.0 Energy MJ/kg 23.7 *The % s are expressed in dry weight relative to the total weight of meal.

[0128] Other Ingredients [0129] Fishmeal LT70 (Peruvian fishmeal LT70: 71% crude proteins (CP), 11% crude lipids (CL), EXALMAR, Peru) [0130] Krill meal (2 to 4% chitin) (Krill meal: 61% CP, 19% CL, Aker BioMarine Antarctic AS, Norway) [0131] Squid meal (Super Prime without viscera: 82% CP, 3.5% CL, Sopropeche, France) [0132] Soy protein concentrate (Soycomil P: 62% CP, 0.7% CL, ADM, Netherlands) [0133] Wheat gluten (VITEN: 84.7% CP, 1.3% CL, ROQUETTE, France) [0134] Maize gluten (Maize gluten meal: 61% CP, 6% CL, COPAM, Portugal) [0135] Soy meal 48 [0136] Whole pea [0137] Fish oil [0138] Rapeseed oil [0139] Pre-mix of vitamins and minerals (PREMIX Lda, Portugal) [0140] Soy lecithin [0141] Guar gum [0142] Antioxidant [0143] Sodium propionate [0144] Monocalcium phosphate [0145] DL-methionine

[0146] Machine for Heat Treatment

[0147] The heat treatment is carried out with a twin screw extruder (CLEXTRAL BC45, France) with a screw diameter of 55.5 mm and a maximum flow rate of the order of 90-100 kg/h. The extruder has been equipped with a round die of size 1 mm and a high-speed cutter for cutting the products to the defined granule size.

[0148] Other Equipment

[0149] Mixing is carried out in a twin propeller mixer (model 500L, TGC Extrusion, France).

[0150] Grinding is carried out in a micro-pulverizing hammer mill (model SH1, Hosokawa-Alpine, Germany).

[0151] Drying is carried out using a vibrating fluidized bed dryer (model DR100, TGC Extrusion, France).

[0152] Coating is carried out in a coater (model PG-10VCLAB, Dinnisen, Netherlands).

1.2. Methods

[0153] Preparation of the Compositions

[0154] Three compositions Y7.5, Y15 and Y25 were formulated, comprising respectively 7.5%, 15% and 25% by dry weight insect meal with respect to the total weight of the composition. These three compositions were utilized in the processes according to the invention. Two other compositions CTRL and Y5 were also formulated for utilization in comparative processes.

[0155] Certain adjustments were made to the formulation of the compositions in order to maintain the isonitrogenous conditions (crude protein, 48.5% by dry weight with respect to the total weight of dry matter (DM)), isolipidic conditions (22.7% by dry weight with respect to the total weight of the DM) and isoenergetic conditions (raw energy, 23.2 MJ/kg of DM).

[0156] All the ingredients (with the exception of the fish and rapeseed oils) were weighed and mixed in the twin propeller mixer according to the different formulations.

[0157] The different mixtures obtained were ground in the micro-pulverizing hammer mill in order to obtain the compositions CTRL, Y5, Y7.5, Y15 and Y20, in the form of powder, the particles of which are smaller than 250 microns in size.

[0158] 60 kg of each composition were prepared.

[0159] The formulations of the compositions are summarized in Table 2 below.

TABLE-US-00002 TABLE 2 Summary of the compositions prepared. Ingredients in %*: CTRL Y5 Y7.5 Y15 Y25 Fishmeal LT70 25.00 20.00 17.50 10.00 0.00 Krill meal 3.00 3.00 3.00 3.00 3.00 Squid meal 5.00 5.00 5.00 5.00 5.00 Insect meal 5.00 7.50 15.00 25.00 Soy protein concentrate 14.00 14.00 14.00 14.00 14.00 Wheat gluten 9.05 9.25 9.40 9.65 10.10 Maize gluten 8.20 8.20 8.20 8.20 8.20 Soy meal 48 7.50 7.50 7.50 7.50 7.50 Whole pea 6.15 5.75 5.40 4.75 3.70 Fish oil 11.50 11.50 11.50 11.50 11.50 Rapeseed oil 6.00 5.80 5.70 5.40 5.00 Pre-mix of vitamins and minerals 1.50 1.50 1.50 1.50 1.50 Soy lecithin 1.00 1.00 1.00 1.00 1.00 Guar gum 0.20 0.20 0.20 0.20 0.20 Antioxidant 0.20 0.20 0.20 0.20 0.20 Sodium propionate 0.10 0.10 0.10 0.10 0.10 Monocalcium phosphate 1.30 1.70 2.00 2.60 3.50 DL-methionine 0.30 0.30 0.30 0.40 0.50 Dry matter (DM), %* 93.4 0.0 93.1 0.0 93 0.1 95.0 0.0 93.2 0.0 Crude protein, % DM** 48.5 0.0 48.5 0.1 48.5 0.0 48.5 0.0 48.5 0.1 Crude fats, % DM** 22.7 0.2 22.7 0.1 22.6 0.2 22.7 0.2 22.7 0.2 Ash, % DM** 9.4 0.0 8.8 0.0 8.7 0.1 8.1 0.0 7.4 0.0 Chitin, % DM** 0.06 0.46 0.66 1.26 2.06 Raw energy, MJ/kg of DM 23.2 0.2 23.2 0.0 23.2 0.0 23.2 0.1 23.2 0.1 Total 100 100 100 100 100 Total without oils (fish and rapeseed) 82.5 82.7 82.8 83.1 83.5 Chitin, % DM without oils (fish and 0.07 0.56 0.80 1.52 2.47 rapeseed) *% dry matter relative to the total weight of the composition **% in dry weight relative to the total weight of the dry matter

[0160] The pre-mix of vitamins and minerals mentioned in Table 2 comprises: [0161] 0.3% by weight vitamin B1 (thiamin), [0162] 0.3% by weight vitamin B2 (riboflavin), [0163] 0.2% by weight vitamin B6 (pyridoxin), [0164] 0.001% by weight provitamin of vitamin B12 (cyanocobalamin), [0165] 2% by weight vitamin B3 (nicotinic acid or niacin), [0166] 0.15% by weight vitamin B9 (folic acid), [0167] 2% vitamin C (ascorbic acid), [0168] 0.03% by weight vitamin B8 (biotin or vitamin H), and [0169] 1% by weight provitamin of vitamin B5 (calcium pantothenate),
the percentages by weight being indicated relative to the total weight of the pre-mix of vitamins and minerals.

[0170] The compositions CTRL, Y5, Y7.5, Y15 and Y25 thus comprise approximately 0.11% % by weight water-soluble vitamins and/or derivatives thereof, of which 0.006% by weight vitamins B6 and B9, relative to the total weight without oils (fish and rapeseed) of the composition.

[0171] Determination of the Quantity of Chitin

[0172] Dietary fibres from insect meal are essentially composed of chitin, the latter was therefore assayed according to the AOAC 991.43 method. The values thus obtained are consequently slightly overestimated.

[0173] Heat Treatment of the Compositions

[0174] The compositions CTRL, Y5, Y7.5, Y15 and Y25 were then extruded with a granule size of 3.0 mm.

[0175] Heat Treatment

[0176] The temperature of the heat treatment carried out during the extrusion is indicated in Table 3 below, for each composition.

[0177] Throughout the extrusion of the different compositions, the operating parameters were recorded and made it possible to calculate the specific mechanical energy (SME), in Watt-hour/kg (Wh/kg).

TABLE-US-00003 TABLE 3 Conditions for the extrusion and SME in Example 1. Temp. Temp. Supply Screw Water Drum 1 Drum 2 rate speed level Amperage SME Diet ( C.) ( C.) (kg/h) (rpm) (0-10) (A) (Wh/kg) CTRL 32-33 120-123 87 234 7.0 15 66.0 Y5 32-33 120-122 90 240 7.0 15 65.5 Y7.5 32-33 119-121 90 245 7.0 14 62.4 Y15 32-33 119-122 93 252 6.5 13 57.7 Y25 32-33 120-123 95 257 6.0 13 57.6

[0178] By Drum 1 is meant a preconditioner, where the mixture originating from the twin screw mixer is brought up to temperature.

[0179] By Drum 2 is meant a conditioner: this is the heat treatment and pressure increase step which takes place in the extruder.

[0180] The water level is an indication of the water added during heating with steam and consequently the quantity added can vary according to the ingredients. It is adjusted by drying on completion of the process.

[0181] The SME was calculated as follows:

[00001]$\mathrm{SME}.Math..Math.\left(\mathrm{Wh}.Math.\text{/}.Math.\mathrm{kg}\right)=\frac{UI\cos .Math..Math..Math.\frac{\mathrm{ESS}.Math..Math.\mathrm{SS}}{\mathrm{Max}.Math..Math.\mathrm{SS}}}{\mathrm{Qs}}$

[0182] Where:

[0183] U: operating voltage of the motor (U=460 V).

[0184] I: current supplying the motor (A).

[0185] cos : theoretical yield of the motor of the extruder (cos =0.95).

[0186] ESS SS: test speed (rpm) of the screws in rotation.

[0187] Max SS: maximum speed (267 rpm) of the screws in rotation.

[0188] Qs: inlet flow rate of the composition (kg/h).

[0189] Drying

[0190] Following the extrusion, the extrudates CTRL, Y5, Y7.5, Y15 and Y25 were dried in the vibrating fluidized bed dryer.

[0191] Coating

[0192] After cooling the granules Y7.5, Y15 and Y25, the fish and rapeseed oils described in Table 2 were added by coating under vacuum, using a coater.

2. Conclusion

[0193] During the extrusion process, increasing doses of insect meal require a reduction in the water added and an increase in the supply rates of the mix and the screw speed, leading to a reduction in the specific mechanical energy (SME).

EXAMPLE 2

Evaluation of the Water-Soluble Vitamins in Granules Obtained According to the Process According to the Invention and According to Comparative Processes

[0194] In order to determine the effect on the preservation of the water-soluble vitamins, samples of the compositions CTRL, Y5, Y7.5, Y15 and Y25 before extrusion, of the extrudates CTRL, Y5, Y7.5, Y15 and Y25 (before drying) and of dried granules CTRL, Y5, Y7.5, Y15 and Y25 (without coating/covering) were sampled for analysis of the vitamin A, B6 and B9 content.

1. Material and Methods

[0195] The quantity of vitamin B6 was determined according to the standard NF EN 14164.

[0196] The quantity of vitamin B9 was determined by HPLC-type or UPLC-type liquid chromatography with UV, RI (refraction index) or MS/MS (tandem mass spectrometry) detection.

[0197] The results of these analyses are presented in Table 4 below.

TABLE-US-00004 TABLE 4 Quantities of vitamins A, B6 and B9 at various stages of the granulation process Composition Dry granule before extrusion Extrudate (without coating) Vitamin A (IU/kg) CTRL 29750 1219 28300 1395 28808 1303 Y5 31395 1445 29382 325 30463 648 Y7.5 30625 601 31183 550 30129 800 Y15 31331 761 29857 1762 30287 1150 Y25 30210 1454 28290 1018 29699 752 Vitamin B6 (mg/kg*) CTRL 23.3 0.6 21.7 0.1 20.7 0.9 Y5 24.1 0.6 22.1 0.1 21.3 0.9 Y7.5 24.8 0.5 23.5 0.4 22.6 0.4 Y15 26.3 0.7 27.5 0.6 25.5 0.6 Y25 26.4 0.0 27.6 1.8 26.8 1.0 Vitamin B9 (mg/kg*) CTRL 16.7 0.7 8.3 0.4 13.9 0.8 Y5 16.1 1.0 10.6 1.4 17.2 0.7 Y7.5 16.8 1.3 12.0 1.7 16.8 1.5 Y15 17.7 0.2 13.4 0.7 17.0 0.1 Y25 16.6 1.2 13.6 1.0 17.2 0.2 *Weight indicated in mg/kg of composition

[0198] The results from Table 4 are shown in FIG. 1.

[0199] FIG. 2 shows the percentage of loss of vitamins A, B6 and B9 during the granulation process for each composition CTRL, Y5, Y7.5, Y15 and Y25.

[0200] The results show that: [0201] The losses of vitamin A (liposoluble) during the granulation were low (2-3%) and the vitamin A was scarcely affected by the presence of chitin. [0202] In a CTRL diet, the losses of vitamins B6 and B9 (water-soluble) during the extrusion varied from 11 to 12%. However, the inclusion of meal containing 15 and 25% chitin tended to significantly reduce the losses during treatment of these two vitamins. This effect of preservation of the water-soluble vitamins can therefore be observed as soon as a chitin content greater than or equal to 0.8% is reached in the composition undergoing the heat treatment, preferably greater than or equal to 1.5%.

EXAMPLE 3

Evaluation of the Quality Criteria of the Granules

1. Material and Methods

[0203] The quality of the granules CTRL, Y5, Y7.5, Y15 and Y25 as prepared in Example 1 was evaluated.

1.1. Moisture Content

[0204] The moisture content of the extrudate (on the outlet of the extruder and before drying) and of the granules (once dried) was measured, by determining the loss of weight after drying of 10 grams of sample (carried out in triplicate) at 105 C. over 24 h.

1.2. Water Activity

[0205] The water activity (aw) represents the vapour pressure of a product divided by the vapour pressure of a pure water at the same temperature. The water activity is commonly used as a criterion for characterizing the duration of preservation of the products, as below certain levels, it inhibits the growth of bacteria and moulds. The water activity was measured on feed samples in triplicate (2.5 g) using AquaLab LITE (DECAGON, USA).

1.3. Apparent Density

[0206] The apparent density of the extruded feed was determined, in triplicate, by filling a pre-weighed plastic volumetric beaker (known volume 1 L) with granules. The excess granules at the top of the plastic beaker were gently scraped off level with the rim. Care was taken to avoid tapping the sample. The plastic beaker was weighed and the apparent density expressed by mass of the sample (g) per volume unit (L).

1.4. Statistical Treatment of the Data

[0207] The data were analyzed by one-way ANOVA. If appropriate, the averages were compared using the Newman-Keuls test. Statistical significance was tested at P<0.05. All the statistical tests were carried out using the SPSS (v21, IBM, USA) software.

2. Results

[0208] The results relating to the quality of the different granules are presented in Table 5 below and in FIG. 3.

TABLE-US-00005 TABLE 5 Apparent density, moisture content and water activity of the experimental feeds Apparent Moisture on density after the outlet of Moisture after Water activity Diet drying g/L the extruder % drying % after drying CTRL 622 5 .sup.e 21.8 0.3 6.7 0.1 0.528 0.006 Y5 582 4 .sup.d 22.2 0.6 6.9 0.1 0.532 0.017 Y7.5 569 2 .sup.c 22.2 0.6 6.7 0.1 0.535 0.009 Y15 521 3 .sup.b 21.8 0.6 6.6 0.2 0.532 0.003 Y25 485 4 .sup.a 21.6 0.9 6.8 0.1 0.531 0.004 The values are averages standard deviation (n = 3). Different letters in superscript in a column indicate a significant difference (P < 0.05).

3. Conclusion

[0209] The apparent density of the extruded granules varied considerably, from 622 to 485 g/L. A significant reduction in the apparent density (P<0,05) was closely associated with the increase in growing doses of the insect meal.

[0210] Whatever the level of inclusion, the insect meal did not affect the moisture content (measured both before and after drying) and the water activity of the extruded feeds.

[0211] It is interesting to note that, for the purpose of maintaining isonitrogenous and isolipidic conditions between the diets, apart from the direct replacement of fish meal with insect meal, the diets rich in insect meal have a slight increase in wheat gluten (from 9.05% in CTRL to 10.10% in Y25) and a reduction in whole peas (from 6.15% in CTRL to 3.70% in Y25). Both wheat gluten and starch originating from whole peas are elements known to affect the expansion and the physical structure of the granules.

EXAMPLE 4

Impact of Chitin on Fish Growth

[0212] The CTRL diet described in Example 1 was formulated with convenient ingredients in order to meet the known nutritional needs of juvenile rainbow trouts. This CTRL diet is composed 25% of fishmeal, 8% of other protein sources of marine origin (squid meal and krill meal), while the remaining protein sources were a concentrate of soy protein, wheat gluten and maize gluten. On the basis of this formulation, the four diets Y5, Y7.5, Y15 and Y25, also described in Example 1, in which the fishmeal was replaced with the insect meal in respective contents of 20, 30, 60 and 100%, were formulated.

1. Material and Methods

1.1. Material

[0213] The Diets

[0214] The 5 diets are constituted by granules having the compositions CTRL, Y5, Y7.5, Y15 and Y25 respectively, as prepared in Example 1.

[0215] The levels of squid and krill meal were kept constant among all the diets, in order to guarantee a high palatability. Minor adjustments were made to the formulation of the diets tested in order to maintain the isonitrogenous conditions (crude protein, 48.5% DM), isolipidic conditions (22.7% DM) and isoenergetic conditions (raw energy, 23.2 MJ/kg of DM).

[0216] The levels of supplementation with methionine and monocalcium phosphate in the diets tested were adjusted in order to correspond to those found in the CTRL feed.

[0217] Throughout the duration of the test, the experimental feeds were stored at ambient temperature, but in a cool, well-ventilated place.

[0218] The Fish

[0219] Triplicate groups of 35 rainbow trouts (Oncorhynchus mykiss), with an initial body weight (IBW) of 5.010.1 g were fed with one of the five experimental diets for 90 days. The fish grew in circular, glass-fibre tanks (volume: 250 L) supplied with a continuous flow of freshwater, at temperatures comprised between 14.10.3 C. and levels of dissolved oxygen above 7.4 mg/L (FIG. 1). The fish were subjected to summer conditions with natural photoperiod changes (May-July). The fish were hand-fed to apparent satiety, three times a day (9:00, 14:00 and 18:00) during the week and twice a day at week-ends (10:00 and 16:00), taking the greatest care to avoid wasting the feed. The feed distributed was quantified throughout the study. Anaesthetized fish were weighed individually at the start and at the end of the study and the group was weighed on day 28 and on day 60. At the start, 15 fish from the same initial stock were sampled and stored at 20 C. for subsequent analysis of the whole body composition. After 90 days of experimental feeding, 6 fish from each tank were sampled for the same purpose.

1.2. Methods

[0220] Criterion for Evaluating Growth and the Use of the Nutrients

[0221] IBW (g): Initial body weight.

[0222] FBW (g): Final body weight.

[0223] Specific growth rate, SGR (%/day): (Ln FBW Ln IBW)100/days.

[0224] Feed conversion ratio, FCR: gross feed ration/weight gain.

[0225] Voluntary feed intake, VFI (% BW/day): (gross feed ration/(IBW+FBW)/2/days)100.

[0226] Protein efficiency ratio (PER): wet weight gain/crude protein intake.

[0227] Statistical Analysis

[0228] The data are presented by the average of three repetitions+standard deviation. The data were subjected to one-factor analysis of variance. Before ANOVA, the values expressed in % were subjected to an arcsine square root transformation. The statistical significance was tested at a probability level of 0.05. All the statistical tests were carried out using IBM SPSS V21 software.

2. Results

[0229] Growth Performance

[0230] The data on the growth performances, feed conversion and protein efficiency of the rainbow trout fed with the experimental diets for 90 days are reported in Table 6. No deaths occurred during the test.

TABLE-US-00006 TABLE 6 Growth performances on day 90 Diet CTRL Y5 Y7.5 Y15 Y25 IBW (g): 5.0 0.1.sup. 4.9 0.1.sup. 5.0 0.1.sup. 5.1 0.1.sup. 5.1 0.1.sup. FBW (g): 42.9 1.3 .sup.a 45.2 1.0 .sup.b 49.0 0.6 .sup.c 51. 0 1.4 .sup.c 55.9 1.0 .sup.d SGR, %/d 2.39 0.06 .sup.a 2.47 0.02 .sup.b 2.54 0.03 .sup.b 2.56 0.05 .sup.b 2.67 0.04 .sup.c FCR 0.93 0.02 .sup.b 0.83 0.03 .sup.a 0.80 0.02 .sup.a 0.79 0.04 .sup.a 0.79 0.02 .sup.a Feed intake, % ABW/d 1.63 0.04 .sup.b 1.48 0.05 .sup.a 1.45 0.04 .sup.a 1.44 0.07 .sup.a 1.47 0.05 .sup.a PER 2.38 0.06 .sup.a 2.68 0.10 .sup.b 2.76 0.06 .sup.b 2.80 0.15 .sup.b 2.74 0.08 .sup.b The values are the averages standard deviation (n = 3). The values within a row with different superscripts differ significantly (P < 0.05).

[0231] Incorporation of increasing doses of insect meal (and therefore of increasing doses of chitin) with a concomitant reduction of fishmeal were progressively linked to a significant increase in the bodyweight of the fish. Furthermore, in comparison with the CTRL treatment, all the diets of insect meals led to a significant reduction in the feed intake and a significant increase in the PER (P<0.05). The introduction of chitin into the granules according to the invention therefore has no drawbacks as regards the nutritional intake delivered to the animal.