Technical design and equipment: Key to improving feed quality and nutrition

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					                               September | October 2010
         Feature title: Technical design and equipment:
          Key to improving feed quality and nutrition
          International Aquafeed is published five times a year by Perendale Publishers Ltd of the United Kingdom.
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The International magazine for the aquaculture feed industry
 F: Equipment                                                                                                                                                                                                                                                                                                       F: Equipment

                                                                                                                                                               adjusted or the materials should be added                                        duction of premix feed
                                                                                                                                                               after pelleting.                                                              3: In case of change of for-
                                                                                                                                                                   As the core process of feed production,                                      mula, the mixer should
                                                                                                                                                               batching accuracy has a direct impact on                                         be thoroughly cleaned to
                                                                                                                                                               feed composition and nutrition absorption                                        avoid cross contamination
                                                                                                                                                               of the animals. As a result, the feed nutrition                               4: Premix should be sepa-
                                                                                                                                                               can be balanced only with appropriate                                            rated from major mixing
                                                                                                                                                               batching system.                                                                 process in order to pre-
                                                                                                                                                                   The batching process has a important                                         vent cross contamination
                                                                                                                                                               effect on batching accuracy and composi-                                      5: The transportation distance
    Technical design and equipment                                                                                                                             tion. The major technical improvements lie                                       and height of materials
                                                                                                                                                               in following aspects:                                                            after batching should be as

    Key to improving feed                                                                                                                                        1: The batching scale must be checked
                                                                                                                                                                    regularly so as to ensure measure-
                                                                                                                                                                    ment accuracy of batching equipment
                                                                                                                                                                                                                                                short as possible and no
                                                                                                                                                                                                                                                conveying equipment like
                                                                                                                                                                                                                                                pneumatic device should be


    quality and nutrition                                                                                                                                        2: The formula should be right and the
                                                                                                                                                                    raw materials can be replaced
                                                                                                                                                                 3: The materials should be fed at proper
                                                                                                                                                                                                                                                adopted as it would cause
                                                                                                                                                                                                                                                separation of materials

                                                                                                                                                                    speed                                                                   Impact of pelleting
     by Shao Jianxin, Engineer, ZCME, China                                                                                                                      4: The control system should be correct                                    on feed nutrition
                                                                                                                                                                 5: The batching equipment must be                                            1. Pellet quality control: pellet




W
                                                                                                                                                                    operated in correct way                                                      quality is the precondition of feed nutri-                 must be unsaturated steam, free from con-
                   hy do some feed facto-                      With the same level of raw material and       after repeated grind would decrease 40              6: The batching equipment should                                                tion which must be strictly manipulated.                   densed water so as to ensure enough ‘pasting’
                   ries earn profits while                formula, the quality of feed only depends          percent.                                               be clean so as to avoid cross                                                The conditioning quality is the primary                    of starch and prevent machine blockage due
                   others don’t? Why do                   on process technology and equipment                    The key point of grain size control                contamination                                                                control point of pellet quality which                      to too much moisture. The steam must go
                   feed of some factories                 performance.                                       technology is to grind each raw material            7: The batching process especially the                                          includes temperature, time, water and                      through a water trap and a pressure reducing
sell well? The reason behind is technical                      As the digest system of chicken, pig, fish,   to the best size suitable for digestion so as          use of medicine should be carefully                                          ‘pasting degree’ of starch. A second-                      valve before entering the conditioner.
design and equipment selection.                           shrimp and pet varies, feed of different size      to ensure the batch feed can acquire best              recorded                                                                     ary control
                                                          and degree of ripeness are demanded. It            raising efficiency and economic profit. It is         No-error computer control technology                                          point covers
    Choosing skilled feed engineering con-                is one of the important methods for the            mandatory to study the best digestion size        is adopted to manipulate batching accuracy.                                       powder
structors and comprehensive solutions                     modern feed companies to improve prod-             of each raw material for different animals as         Micro additives can be premixed and                                           rate, cooling
                                                                                                                                                                                                                                                                                                       The event that
                                                                                                                                                                                                                                                                                                       GROWiNG iS
providers are also vital for the success of               uct quality by upgrading process technology.       shown in Table 1.                                 batched and high accurate batching system                                         tempera-
a company.
    The factors affecting feed quality can be
                                                               Impact of grain size on feed nutrition
                                                               Generally, grain size should take con-
                                                                                                                 Pulverization and micro-pulverization
                                                                                                             must be applied for aquatics feed.
                                                                                                                                                               can be adopted.                                                                   ture, mois-
                                                                                                                                                                                                                                                 ture, blade-
                                                                                                                                                                                                                                                                                                        will energize
                                                                                                                                                                                                                                                                                                          your BUSINESS
                                                                                                                                                                                                                                                                                                        beautiful
summed up in three aspects, namely:                       sideration of many factors like feeding                Research has shown that carp feed ratio       Impact of mixing                                                                  even degree
  • The quality of raw material                           method, process costs, capacity and growing        could raise 5-10 percent if the screen of         conformity on nutrition                                                           and water
  • The feed formula                                      characteristics of animals.                        grinder has been reduced from 1.5mm,                  Conformity is vital for feed quality as it                                    durability
  • The process technology                                     Its empirical value should be no more         1.2mm to 1.0mm, 0.8mm, 0.6mm. As a                will determine whether the animal can get                                         of the feed.
                                                                              than 1/3 of the diameter       result, grain size has a markable influence       full nutrition from the feed. The air balance                                     To       meet                  VI INTERNATIONAL
                                                                                                                                                                                                                                                                                  AQUACULTURE
Table 1: International best grinding particle size                            of pellet.                     on variation of nutrition.                        between mixing bin and mixer also has an                                          the above
                                                                                                                                                                                                                                                                                     EXHIBITION
                                                                                  Appropriate grain size         Grain with excessive small or big diam-       impact on nutrition.                                                              require-
                                                         Best size
                                                                              can improve digestion          eter could break into layers which would              Too big finish product bins and pellet                                        ments man-
                                                     recommended
        Animal              Raise stage                    (µm)               rate of the nutritious         affect the digestion rate of feed nutrition. It   bins and too long transportation lines will                                       ufacturers
                                                                              element. Research has          is only by selecting proper technical design,     destroy conformity of feed and reduce the                                         need proper
                                                                              shown that if the even         professional company and equipment can            conversion rate of the animal.                                                    steam supply
                       Ablactation 0~14d                   300                size of corn feed for sow      good quality feed be made.                            It is critical to choose the right mixer,                                     and control
             Pork      Ablactation 14~35d                  400                is reduced from 1200um                                                           mixing period and feeding method in order                                         systems,
           Grice                                       ≤500�Corn�             to 400um, its digestion        Impact of batch on                                to ensure conformity and nutrition. The                                           conditioning,
   Fattening pig                                     500~600�Corn�
                                                                              rate could be raised by        feed nutrition                                    control of mixing conformity covers mixing                                        pelleting,
                                                                              14 percent, dry materi-           Formula is a major impact factor for feed      feed, concentrated feed, additives, premix                                        cooling and                                                                              October 20th to 23rd
             Sow                                     500~600�Corn�            als in manure could be         nutrition and pellet quality. Formula with        feed and liquid feed.                                                             screening                                                                                Puerto Montt - Chile
   Growing pig               15~30kg                    323(batch)                                                                                                                                                                                                                                                                         www.aqua-sur.cl
                                                                              reduced by 21 percent          high content of grain like corn and soybean           The technical improvements in batching                                        equipment
        Dorking                                      700~900�Corn�            and the nitrogen would         cannot produce high quality pellet feed due       process have the following aspects:                                               with         all
                                                                              be lowered by 31 percent.      to the lack of natural bond.                        1: Proper mixer must be selected to                                             control
                                                           900
                                                                                  Over grind could lead         Addition of highly cohesive wheat can               ensure conformity                                                            parameters
                                                                                                                                                                                                                                                                               Last available stands: book now!
      Beef cattle                                  1~1.5cm�straw�corn stalk�                                                                                                                                                                                                   María Paz / mpfernandez@aqua.cl / +56-2 756 5402 / +56-9 9547 7589
                                                                              to more consumption of         improve pellet quality.                             2: The materials should be added in cor-                                        scientifically




                                                                                                                                                                                                                                                                        FRANCE / 00 33 2 97 40 42 09
                                                       2~7cm�corn
                                                                              energy, less capacity and         It is necessary to combine each element             rect order with big materials added                                          adjusted.
                                                        stock�hay�                                                                                                                                                                                                                    Our hydrolysates have a superior concentration of Natural Active Nutrients
                                                                                                                                                                                                                                                                                                                                                 TM


                                                                              destroy of nutrition of        in the formula and keep fat to lowest                  at first and small ones added later. All                                    The steam                SponSorS                                                                 organizerS
                                                                                                                                                                                                                                                                                        Thanks to their biological action on fish and shrimp growth mechanisms,
             Fish                                    ≤0.5mm�batch�                                                                                                                                                                                                                       they boost your feed performance and help you substituting fish meal.
                                                                              feed. The research data        limit. In case of large proportion of adding           materials should be added in proper                                     fed into con-
          Shrimp                                        150~175               proves that VA of pellet       materials, the condition process should be             amount and order especially for pro-
                                                                                                                                                                                     12 | InternatIonal AquAFeed | September-october 2010   ditioning units                                    contact@aquativ-diana.com - www.aquativ-diana.com


                                                                                                                                                                                                                                                                            IAF10-05.indd 13                                                               07/09/2010 14:55




                                                 32 | InternatIonal AquAFeed | September-october 2010                                                                                                                                September-october 2010 | InternatIonal AquAFeed | 33
     F: Equipment                                                                                                                                                                                                                                                                 F: Equipment
                                                                                                                                                                                                                                                                                      F: Binders
Table 2: Anti-nutritional factors of common raw materials of feed
Anti-                                                                                                                   ing of feed with vitamins is as         Table 1: Composition of test dietsfor specific
                                                                                                                                                                   material of specific size                       of security, Results and nutrition of
                                                                                                                                                                                                                                  sanitation                            of anti-nutrition factory and keep vita-
                                                                                                                        following: temperature ≥90°C,                 animals.Ingredientdenaturation hasDiet PBP feed,UF is necessary h i n g
                                                                                                                                                                                 Protein                   little          it                            Table 2: Leaching rate enzymes uptake of test diets
                                                                                                                                                                                                                                    L e a c to equip residue-           mins; and water preparation cannot only
nutritional                                                                                                                                                                                  Diet WG                Diet
factors          Distribution            Inhibit function                                                               moisture≥15%, time ≥60 seconds.               influence on amino acid but improves         free conveyor and bins, apply scientific Sample
                                                                                                                                                                                                                                 rate and water                                  Diet effect Diet PBP
                                                                                                                                                                                                                                                                        erase toxicWG of feed but also provide
                                                                                                                                                                                                                                                                                                             Diet UF
                                                                                                                        As a result, it is necessary to               its absorption rate greatly so that                         of cleaning and
                                                                                                                                                                                                                   technology uptake - Analysis sequencing.             a health function.
                                                                                                                                                                              Corn gluten       11            11      12,5
     Protease            Pea seed, beet            Restrain activity of trypsin and pepsin, facilitate secrete of       choose formulation with sound                 protein can be highly utilised.              Heat treatment technology should be
                                                                                                                                                                                                                                 for leaching rates                         Getting rid of anti-nutrition factors in
                                                                                                                        thermal stability. A good pellet                        Fish meal       20
                                                                                                                                                                  6. The impact of post-cooking: after        20       20
                                                                                                                                                                                                                   applied which includes cooking atWater uptake materials has 105,13% vital in selec-
                                                                                                                                                                                                                                 and water uptake            high       raw 107,63%            become        89,89%
     inhibitor              broomcorn                                                                  pancreas
                   Rapeseed, cabbage,
                                                                                                                        conditioner, correct air admission                                      31
                                                                                                                                                                      conditioning,flour ‘paste’ degree and
                                                                                                                                                                              Wheat the                       31       31        were done high-pressure rate of process technology and equipment.
                                                                                                                                                                                                                   temperature, extrusion, at               Leaching    tion      7,75%         8,29%         6,75%
   Glucoside                   Kale, etc           Prohibit growth, increase cardiolipin and reduce appetite            and mixing methods are also the               water durability of pellet should be
                                                                                                                                                                             Pro-Bind Plus        -            2   treatment and ultraviolet irradiation, etc.
                                                                                                                                                                                                                         -       the       labora-                      Feed quality and nutrition can be only
                                                 Impair intestinal wall, lose more endogenous protein, inhibit
                                                                                                                        vital factors for pelleting process.          improved, however, some thermal              With the comprehensive application of ibility as verifiable in Lemos et al. technol-
                                                                                                                                                                                                                                 tory of CreveTec.                      be guaranteed using professional (2009).
                                                                                                                                                                           Wheat gluten          2              -        -
        Lectin                Pea seed                                                                    growth        3. Feed enzymes: pellet proc-                 alert vitamins are destroyed. As a           the above technology, the finish pellet Feed and equipment. With the development
                                                                                                                                                                                                                                 Leaching was done during one           ogy samples with PPD (Predicted Protein
                                                                                                                                                                     Urea-formaldehyde
                                                                                                                        ess also affects feed enzyme and              result, it is better to use- formulations -      0,5
                                                                                                                                                                                                                                 hour satisfactory quality and Digestibility) from 90.7 to of professional
                                                                                                                                                                                                                   feed can obtain in fresh water.                      of nutrition, technicians 92.0% may be
                    Pea seed and cake,
                                                                                                                        other microbials.                                         Other *       7,5
                                                                                                                                                                      with sound thermal stability or apply   7,5      7,5
                                                                                                                                                                                                                   nutrition.       As could be expected                company of high to better methods to
                                                                                                                                                                                                                                                                      consideredcan work out very high protein
       Tannin                        etc                         Weaken absorption of protein, carbohydrates
                                                                                                                        Enzyme and microbial are bio-                       improved coating technology so
                                                                                                                                                                      the Crude protein       37,74         38,01    38,05       from previous results, the           digestibility anti-nutrition factors and make
                                                                                                                                                                                                                                                                        eliminate diets.
                                                injures gastric mucous membrane, destroy metabolization of
    Gossypol       Cottonseed and cake                                                         protein and iron         logical products, the activity of             as to Crude lipid nutrition values 8,66
                                                                                                                                                                                preserve       8,61            of  Impact of technical process
                                                                                                                                                                                                                      8,63       inclusion of ureumformal-              more contribution in improving feed quality
                                                                                                                        which are usually damaged under               the feed as much as possible; which                        dehyde reduces in feed can Growth trial
                                                                                                                                                                                                                        The anti-nutrition factors   the water          and nutrition.
                                          Interfere biological effectiveness of mineral elements, form protein                                                               Crude fibers      2,92          2,91     2,94
  Phytic acid                 Pea seed                                                                  complex         the comprehensive function of                 is mostly used in the production of                        uptake that
                                                                                                                                                                                                                   cause disease of pigs andinpets and retard
                                                                                                                                                                                                                                                 turn reduces              Experimental system - Shrimp were put
                                                                                                                                                                              Ash content      6,44          6,48     6,47
                                                                                                                        high temperature, humidity and                aquatics feed or special aquatics feed       the growth the leaching rate. The values
                                                                                                                                                                                                                                  process. As they are closely in 12 nets of 150 liters each. The nets were
   Saponine                    Soybean                         Destroy absorption of nutrition, reduce appetite                                                  * Canola, Soybeanexample. oil, Soybean lecithin,
                                                                                                                        pressure. It is reported that the             for shrimp for meal, Fish                    related with for the three diets are within
                                                                                                                                                                                                                                  process technology, nutrition- submerged in a bigger tank, which is con-
        Lignin                  Pasture                        Destroy absorption of nutrition, reduce appetite                                                  premix                                                                                                    More inforMation:
                                                                                                                        activity of phytase drops by 87.5         7. Impact of storage and transportation:                       standards.
                                                                                                                                                                                                                   ists have developed many methods to elimi- nected to a biofloc reactor. Water quality
     Alkaloid                   Pasture                                         Reduce appetite, inhibit growth         percent at temperatures of over               cross contamination usually takes            nate anti-nutrition factors.                       is maintained through bioflocs and is the
                                                                                                                                                                                                                                                                           ZCME
                                           Facilitate pasting of materials inside enteron, weaken absorption            80�.                                          place during storage and transporta-
                                                                                                                                                               binders or natural binders on the digest-          Digestibility                                            Floor all nets. There were four replicates
                                                                                                                                                                                                                        However, the nutrition elements same in 25th, Friendship Building No.159
          NSP               Grain feed                                                                of nutrition                                                                                                                                                         Zhao Jia Bang Rd Shanghai
                                                                                                                        So the utilisation rate of N.P. will            of the feeds in transportation
                                                                                                                                                               ibilitytion. Residue growth of shrimp vehi-              feed would lose feed were analysed
                                                                                                                                                                                                                   in The three samples of at the same time. for each diet.
                                                                                                                                                                                                                                                                           PC:200032
                                                                                                                        be affected. The microbe addi-                cles, bins, buffer hoppers and process       Extrusion digestibility with the pH stat
                                                                                                                                                                                                                  for in vitroand expansion at high tempera-               PR China
       Meanwhile, the flow rate of steam must             High temperature conditioner with short                  tives in the feed is especially reactive    Material and Methods contami-
                                                                                                                                                                      equipment could cause cross                  ture can improve by Lemos et and limit Shrimp21 64188282
                                                                                                                                                                                                                  method, as described feed quality al (2009).             Tel:+86
   be matched to the feeding rate. As a result,       time (60-160 seconds) can kill bacteria.                     to high temperature so that its activity        Diets - Three different diets were are
                                                                                                                                                                      nation. Harmful microbe and pests for-       lost of nutrition; anoxia sterilisation could
                                                                                                                                                                                                                  DH values were used to predict protein                   Each net 64163299
                                                                                                                                                                                                                                                                           Fax:+86 21 was stocked with 25 shrimp
   steam with proper characteristics is a                 Many conditioners of this type have been                 will be lost completely if the pellet              also source of Feeds were pelleted
                                                                                                                                                               mulated (see table). cross contamination. on        kill bacteria effectively models relating
                                                                                                                                                                                                                  digestibility by separateand keep vitamins; (Litopenaeus vannamei) of 12-13g each.
   precondition of pellet quality.                    developed in several countries. The durabil-                 temperature exceeds 85�. It is better             To meet increasingly high demand ingredients or could eliminate vivo digest-
                                                                                                                                                               a 2mm die.                                          fermentation diet DH to in toxic effect They were acclimatised in the nets during
       Technical improvements of steam pres-          ity of feed at high temperature should also                  to coat enzyme after pelleting or
   sure and flow rate covers following aspects        be considered during conditioning.                           to use enzymes with better thermal
   to ensure high quality of feed:                      1: Materials with bad durability under                     stability.
     1: Control the conditioning of meals,                 high temperature and poor ‘strength’                 4. Impact on anti-nutrition factors:
        including the adding of steam and oil,             should avoid conditioning at high                       part of anti-nutrition factors and
        and check the quality of steam and
        keep a good record of it
                                                           temperature. Instead, they should be
                                                           coated later so as to ensure pellet
                                                                                                                   harmful substances will be killed
                                                                                                                   during the conditioning of pellet.
                                                                                                                                                                                              fr
                                                                                                                                                                                   Contact us bout
     2: Control the product from the pellet
        mill and keep record of it
                                                           quality.
                                                        2. The impact on vitamins: it is vulner-
                                                                                                                   Anoxia sterilisation before pelleting
                                                                                                                   can kill various bacteria effectively
                                                                                                                                                                                               o
                                                                                                                                                                                   more info apowder
                                                                                                                                                                                  Hemoglobin
     3: Control the cooling time, moisture                 able to increase conditioning time                      and improve feed quality. It has been
        and temperature of feed in accord-                 and raise temperature as the vitamins                   a key research subject for profes-
        ance with the room temperature and                 with poor thermal stability would be                    sional technicians.
        moisture                                           easily lost during the pelleting process.               Animals have different reactions to the
     4: Control the fat coated on the surface              Vitamins like A, E, C, thiamine hydro-                  same anti-nutrition factors as its spe-
        of feed                                            chloride, etc will be killed rapidly                    cies and age vary. The anti-nutrition
     5: Check the hardness of pelleted feed                as the temperature and conditioning                     factors can be divided into positive
        and keep good records                              time is raised.                                         inhibitors for carbohydrate, miner-
       Conditioning process is vital for pellet         The critical condition for condition-                      als and prolease, etc. The pelleting
   quality. The mixed materials with                                                                                          process adopts conditioning,
   high content of grain usually stay                                                                                         high temperature extrusion
   for at least 40-60 seconds in the                                                                                          methods to weaken the anti-
   conditioner.
                                                                                                                                                                        SO NATURAL
                                                                                                                              nutrition factors as listed in
       Meanwhile, the temperature                                                                                             Table 2 to maximum limit.
   inside the conditioner should be                                                                                           5. Impact of pellet on starch
   kept between 85-98� to improve                                                                                             and protein: the starch would             Natural ingredients for aqua feed                         • Pro-Bind Plus, a nutritional, gelatin based pellet binder,
                                                                                                                                                                        Whether you’re looking for a natural EU                     especially for pelleted (shrimp) feed.
   ‘pasting’ of starch. Materials with                                                                                        become ‘pasted’ and protein
                                                                                                                                                                        and USDA approved pellet binder for your                  • Blood meal, a fish meal alternative, especially for
   high fibers must stay for shorter                                                                                          would be denaturated after
                                                                                                                                                                        production of stable pellets or nature’s best               carnivorous fish species.
   time in the conditioner. In case of                                                                                        conditioning so that the ani-             alternatives for fish meal, you can contact                • Muco-Pro®, high contents of natural proteins,
   addition of liquids like molasses,                                                                                         mal can digest and aborb the              Sonac. Sonac produces valuable and essential                amino acids and peptides.
   the materials should stay longer in                                                                                        starch and protein better.                ingredients for the production of aqua feed.              • Hemoglobin Powder, high protein content and good
   conditioner (maximum 30 minutes)                                                                                           However, it is the technical                                                                          digestibility, for better feed conversion
   so that it would absorb molasses                                                                                           issue of a professional com-                                                                                                                                       www.sonac.biz
   fully.                                                                                                                     pany to determine the raw


                                                    10 | | InternatIonal AquAFeed | September-october 2010
                                                     34 InternatIonal AquAFeed | September-october 2010                                                                                                          September-october 2010 | | InternatIonal AquAFeed | 35
                                                                                                                                                                                                                  September-october 2010 InternatIonal AquAFeed | 11
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                                         VO L U M E 1 3 I S S U E 5 2 0 1 0
                                                                                                                           •	 See	the	full	issue
                                                      Influence of natural and
                                                              artificial binders
                                                     - in feeds for Litopenaeus vannamei
                                                                                                                           •	   Visit	the	International	Aquafeed	website
                                                                  on digestibility & growth


                                                                              Ecobiol Aqua
                                                     - the effective single strain probiotic
                                                                                                                           •	   Contact	the	International	Aquafeed	Team
                                                        A general overview
                                                      aquaculture in the EU

                                         Abalone feed development
                                                    in South Africa                                                        •	   Subscribe	to	International	Aquafeed
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DOCUMENT INFO
Description: Why do some feed factories earn profits while others don’t? Why do feed of some factories sell well? The reason behind is technical design and equipment selection.