The hottest survey dairy products and packaging II

Overview of dairy products and packaging (II)

sterile packaging materials for sterile packaging materials, the following properties are generally required

1. Thermal stability: there is no chemical or physical change during aseptic heat treatment

2. Chemical resistance and UV resistance: the organic structure of the material will not change after the adjustment of the hardness tester during the aseptic treatment with chemical agents or ultraviolet rays

3. Thermoforming stability: during aseptic treatment or 1000 system heat treatment, the shape of the container will not change significantly

4. Gas resistance: on the one hand, it can block the infiltration of oxygen in the external air; On the other hand, it can keep the inert gas filled into the container from seeping out

5. Moisture resistance: prevent the penetration of moisture to maintain the moisture content of the product

6. Toughness and rigidity: with appropriate toughness and rigidity, it is convenient for mechanized filling and sealing

7. Lightproof: block the penetration of light

8. Hygiene: the material should be non-toxic, meet food hygiene standards, and easy to sterilize

9. Economy: rich sources and low cost

materials used in different packaging forms

1 Aseptic brick

aseptic brick is made of paper, aluminum and plastic composite laminates, with a thickness of about 0.35mm. The typical structure is Tetra Pak: PE/paperboard/adhesive layer/Al/PE/PE; Kangmei bag: PE/white cardboard/PE/Al/adhesive layer/PE. The inner layer is used to heat seal and contain food. The aluminum foil provides the best oxygen, water and light resistance. The bonding layer connects the aluminum foil with the paperboard. The paperboard provides rigidity and printability. The outer layer of these materials has been widely used to protect PE ink and paperboard

2. Sterile pillow

sterile pillow is also a multi-layer paper, aluminum and plastic composite material, which is close to brick bag, but the paperboard material is different. Its structure is: PE/paper

/adhesive layer/Al/adhesive layer/PE. The paper is a printing layer, which can be flexographic printing or offset printing, and has good barrier and light resistance

3. Roof pack

roof type packaging materials, one is PE/paperboard/adhesive resin/aluminum foil/adhesive resin/PE, which has a shelf life similar to brick pack; The second is the fresh layer of PE/paperboard/PE three-layer structure. Usually, the roof package generally refers to three-layer composite materials

4. Aseptic cup

aseptic cup is represented by ECKA cup (NAS). The aseptic packaging materials of ECKA cup (NAS) are divided into three parts: cup material, cover material and commercial standard material. Its structure and production process requirements are relatively complex. The packaging materials used in the aseptic packaging system of NAS plastic cups are called neutral

aseptic packaging materials, or NAS sheets for short. Its structure is: PP/PE/EVA/EVOH/hips; PP／PE／EVA／PVDC／HIPS； PP／PE／EVA／PS／PVDC／HIPS。 PP layer is aseptic protective layer, PE layer is sealing layer and waterproof layer, EVA is adhesive layer, PVDC and EVOH are barrier layers. The structure of aseptic cup cover material is Al/PE/EVA/PP, Al/PE/EVA/PET. PP and pet are protective layers, PE film is porous film, and Al foil can uncover the beverage hole. The trademark material structure of sterile cup is Al/PE/paper/hot melt adhesive structure

5. Aclin bag

aclin bag material is single-layer structure, and the material is 70% ca-co3 + 30% PP, PE. It is a kind of packaging material with good environmental protection and barrier

6. Fenbao, Baili Bao

Fenbao and Baili Bao can use a variety of composite packaging materials, the first is aluminum-plastic composite film, the second is three-layer black-and-white film (PE + white mother/PE + white mother/PE + black mother), and the third is PE + white mother/adhesive resin/EVOH/adhesive resin/PE + black mother. The shelf life of materials with different structures varies greatly

7. Soft plastic bag

in addition to the common three-layer and five layer coextrusion film materials, there are the following materials:

① single layer plastic film: the structure is LDPE + LLDPE + white mother blown film

② PVDC coating film: the structure is PVDC/three-layer coextrusion film

③ PE aluminized film: the structure is printed layer/PE/PE/vmpe. ④ Dry composite membrane: its structure is BOPP/PE, and its structure is not commonly used

it is mainly composed of "ghost fishing gear" 8 Paper cup

the paper cup is composed of a cup body and a cover material. The structure of the cup body is PE/paper/PE, and the structure of the cup cover is PET/Al/LDPE

9. Plastic cup

plastic cup materials are mainly PP and PS. PP cup has smooth surface and good temperature resistance, and PS cup has good stiffness and low temperature resistance

10. Plastic bottles and barrels

plastic bottles are made of HDPE, PP and pet, and plastic barrels are generally made of hPPE

aseptic packaging system

aseptic packaging of dairy products basically consists of three parts: first, pre sterilization of dairy products; Second, the sterilization of packaging materials or containers; The third is the sterility of filling and sealing environment

the process of aseptic packaging is: Dairy sterilization → packaging material molding → sterilization → aseptic packaging → aseptic products

1 Liquid milk sterilization

low temperature long-time sterilization: 63 ℃, 30 minutes

high temperature short-time sterilization: 80 ℃ - 85 ℃, 1 the structural deflection value is greatly reduced by 0-15 seconds

ultra high temperature instantaneous sterilization: 135 ℃ - 140 ℃, 3-4 seconds

the first two kinds of sterilization are also called pasteurization