This document specifies the grading, specifications, packaging, storage and transportation requirements for fresh Agaricus bisporus.
This standard applies to white fresh Agaricus bisporus produced in factory environments, including both root-bearing mushrooms and trimmed mushrooms.
2 Normative references
The contents of the following documents contribute to this document through normative reference. For referenced documents with dates, only those specific versions apply; for undated referenced documents, their latest versions (including all amendments) are applicable.
GB 2760 National Food Safety Standard: Standards for the Use of Food Additives
GB 4806.7 National Food Safety Standard: Plastics and Plastic Products Intended to Come into Contact with Food
GB/T 23190 Agaricus bisporus
NY/T 658 General Rules for Packaging of Green Foods
3 Terms and Definitions
No terms or definitions need to be defined in this document.
4 Grading
4.1 Basic Requirements
According to the provisions and allowable errors for each grade, fresh Agaricus bisporus in the same packaging should meet the following requirements:
a) No unusual odors or tastes;
b) Free from moldiness, rotting, insect damage;
c) During harvesting and packaging, root-bearing mushrooms should not have large chunks of soil at their bases; trimmed mushrooms should have their stems cut cleanly without soil attached;
d) Free from insects, hair, animal excrement, metal particles, etc.;
e) Physical and chemical requirements and hygiene standards comply with GB/T 23190;
f) Preservatives, anti-corrosives, additives used in packaging, preservation, storage, and transportation should meet GB 2760.
4.2 Grading Division
Under the condition of meeting basic requirements, fresh Agaricus bisporus is classified into Grade I, II, and III, as specified in Table 1.
Table 1: Grades
| Appearance and Morphology | Quality Impacting Surface Characteristics |
|---------------------------------|-------------------------------------------|
| Grade I | White or creamy white. The body shape is round, full. Cap is circular or nearly circular; stem is cylindrical. Membrane tightly enclosed, no spots, undamaged. |
| Grade II | White or creamy white. Body somewhat round and plump; cap near-circular; stem near-cylindrical. Membrane slightly thin with some spotting, slight deformation, minor abrasions. |
| Grade III | White or creamy white. Basic mushroom morphology. Light brown or light gray coloration; spots present; deformities noted; hollow or cracked stems; membrane nearly ruptured; mechanical damage. |
4.3 Allowable Deviations
By weight:
Grade I allows up to 5% of products not meeting this grade’s criteria but conforming to Grade II;
Grade II allows up to 8% of products not meeting its criteria but conforming to Grade III;
Products in Grade III should meet basic requirements.
5 Specifications
5.1 Specification Division
Fresh Agaricus bisporus is classified based on the diameter of their caps into four sizes, as specified in Tables 2 and 3 for root-bearing mushrooms and trimmed mushrooms respectively.
Table 2: Root-Bearing Mushrooms
| Cap Diameter (cm) | Stem Length (cm) |
|-------------------------|------------------|
| Small | 2.1-3.0 | ≤2.0 |
| Medium | 3.1-4.0 | ≤2.5 |
| Large | 4.1-5.0 | ≤3.0 |
| Extra-Large | 5.1-6.0 | ≤3.5 |
Table 3: Trimmed Mushrooms
| Cap Diameter (cm) | Stem Length (cm) |
|-------------------------|------------------|
| Small | 2.1-3.0 | ≤1.0 |
| Medium | 3.1-4.0 | ≤1.5 |
| Large | 4.1-5.0 | ≤2.0 |
| Extra-Large | 5.1-6.0 | ≤2.5 |
5.2 Allowable Deviations
Grade I allows up to 5% of products falling into the next size category;
Grade II allows up to 8%;
For Grade III, products should meet basic requirements.
6 Packaging
Packaging materials must comply with GB 4806.7.
7 Storage and Transportation
7.1 Pre-Cooling
7.1.1 Vacuum Cooling
Stacking method is used for cooling equipment; each batch should not exceed 80% of the device capacity. Pre-cooling time is within 30 minutes, aiming to lower mushroom body center temperature below 4°C.
7.1.2 Cold Storage Pre-Cooling
Pre-cold temperatures range from 0°C to 3°C; single entry volume is between 10% and 30%. Cooling time does not exceed 24 hours, with a target of reaching pre-cooling temperature.
7.2 Storage
Packaged Agaricus bisporus should be stored in refrigerated warehouses at 1°C to 4°C; storage period shouldn't exceed 5 days.
7.3 Transportation
Transportation should use cold-chain methods with temperatures between 1°C and 8°C. Duration of transportation should not exceed 24 hours.