影響水產(chǎn)飼料水中穩(wěn)定性的四大因素

來源： 赤峰和美嘉科技有限公司  點擊：12次 發(fā)布時間：2016-9-19

水產(chǎn)顆粒飼料的水中穩(wěn)定性是指飼料入水浸泡一定時間后，保持組成成分不被溶解和不散失的性能。一般以單位時間內(nèi)飼料在水中的散失量與飼料質(zhì)量之比來表示，也可用飼料在水中不潰散的最少時間來表示。通常要求魚飼料的散失率小于20％(浸泡30min)。影響水產(chǎn)飼料水中穩(wěn)定性的因素有：

一、粘合劑

 粘合劑是魚用飼料中起粘合成型作用的添加劑，大致可分為天然物質(zhì)和化學合成物質(zhì)。前者按成份可分為糖類（淀粉、小麥粉、玉米粉等），和動物膠類（骨膠、皮膠、魚漿等）；后者有羧甲基纖維素，聚丙烯酸鈉等。在使用飼料生產(chǎn)過程中，添加適量的粘合劑可以提高飼料水中穩(wěn)定性，粘合劑的粘合強度除與本身的性質(zhì)有關(guān)外，還與飼料種類、加工條件等因素有關(guān)。

二、粉碎粒度

 粉碎細度對于魚用飼料顆粒水中穩(wěn)定性影響很大，原料粉碎粒度過大，其相應(yīng)的表面積減少，導致原料表面上的淀粉在制粒調(diào)制過程中不能完全糊化，影響粘結(jié)作用，浸水后水分易浸入飼料顆粒而發(fā)生潰散。一般魚用配合飼料的原料經(jīng)粉碎后應(yīng)通過40目標準篩，60目標準篩篩上物≤20%，而對蝦飼料原料要求能通過60目標準篩。

三、調(diào)質(zhì)

 飼料成型的關(guān)鍵在調(diào)質(zhì)。調(diào)質(zhì)是通過高溫、高壓的蒸汽作用于飼料，使淀粉糊化，蛋白質(zhì)變性，增加其粘結(jié)性和可塑性，保證飼料結(jié)構(gòu)細密，具有適當?shù)挠捕龋�水中穩(wěn)定性好。為了起到調(diào)質(zhì)的效果，除了掌握好調(diào)質(zhì)時間，調(diào)質(zhì)溫度外，還應(yīng)選用飽和蒸汽，并保持穩(wěn)定、恒壓，避免使用濕熱蒸汽。對于粗蛋白≥30%的水產(chǎn)飼料，適宜的蒸汽壓力為0.3-0.4MPa，調(diào)質(zhì)溫度80-95℃。

四、環(huán)模

 環(huán)模壓縮比（深徑/孔徑）的大小對魚飼料水中穩(wěn)定性也有一定影響，壓縮比大的環(huán)模壓制出來的飼料顆粒硬度大，結(jié)構(gòu)緊，飼料耐水時間長，反之則短，正常環(huán)模壓縮比為14-17，對蝦料17-20。

The English version

Aquatic particles feed water stability refers to the feed into the water after soaking time, maintain the performance of the components were not dissolve and is not lost. General feed per unit time in the water loss quantity and the quality of feed ratios, are also available to feed in the water not pieces to represent the minimum time. Usually require fish feed the loss rate of less than 20% (soak 30 min). Factors affecting the stability of the aquatic feed water are:

A, adhesives

Adhesive is bonded molding role in fish feed additives, can be roughly divided into natural substances and chemical substances. The former can be divided by ingredients, sugar, starch, wheat flour, corn flour, etc.), and animal glue, bone glue, hide glue, fish paste, etc.); The latter has a carboxymethyl cellulose, sodium polyacrylate, etc. In the process of the use of feed production, adding the right amount of binder can improve the stability of feed water, adhesive bonding strength in addition to the concerned with nature of itself, is also related to such factors as the type, feed and processing conditions.

Second, the crushing granularity

Grinding fineness for fish feed particles has great influence on the water stability, raw material grinding particle size is too large, the corresponding surface area to reduce, lead to the raw material on the surface of the starch in the process of granulating modulation is not fully gelatinization, binding effect, after flooding water immersion feed particles easily and happen to pieces. General fish with compound feed raw material after crushed by 40 goals screen, 60 goals must sieve sieve content 20% or less, and shrimp feed raw material requirements through 60 goals screen.

Third, quenched and tempered

The key on feed molding. Conditioning is applied to feed through high temperature and high pressure steam, the starch gelatinization, protein denaturation, increase the cohesiveness and plasticity, guarantee the fine feed structure, have moderate strength, water stability is good. In order to help the effect, in addition to mastering the tempering time, tempering temperature, also should choose saturated steam, and maintain a stable, constant pressure, avoid damp and hot steam. For aquatic feed crude protein 30% or higher, suitable for steam pressure of 0.3 to 0.3 MPa, tempering temperature 80-95 ℃.

Four, ring die

Ring die compression ratio (deep diameter/size) size also has a certain influence on the stability of fish feed water, large ring mould compression ratio of feed grain hardness, tight structure, feed water resistant time is long, short, conversely normal ring die compression ratio for 14 to 17, prawn 17-20.