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The grade for blueberries is Canada No. 1.

Compulsory Inspection

Interprovincial Trade

All blueberries grown in Newfoundland are subject to a compulsory inspection. A release permit could be issued on lots leaving this province. Blueberries grown in New Brunswick, Prince Edward Island and in Nova Scotia and packed in containers having a capacity of 6 litres or less are subject to a compulsory inspection.



Only blueberries grown in Newfoundland are subject to an export compulsory inspection.


The following general inspection exceptions do not apply to blueberries shipped from the provinces of New Brunswick, Prince Edward Island and Nova Scotia and from the above mentioned states:

  • blueberries donated to any organization that qualifies as a registered charity under the Income Tax Act;
  • blueberries carried on any vessel, train, motor vehicle, aircraft, or other means of transport for use as food for the crew or passengers thereof; and
  • shipments of the blueberries consisting of not more than 15 containers.

Method of inspection

Temperature: The temperature of blueberries is difficult to obtain. It is therefore necessary to penetrate the thermometer deep enough into the centre of the container in order that the line mark is inserted into the produce.

The temperature may vary from one container to another and even inside the one container. It is necessary to take the temperature of numerous samples within the lot and even more desirable to take more than one temperature in the same container. Record a temperature range on the certificate, but show the individual temperatures on the details.

Sampling: When sampling trays of blueberries, sample as many trays as is required by the sampling plan from all areas of the load. Keep in mind that this is a minimum rate. Trays of 12 pints require that you inspect 2 pints at random from each tray.

When inspecting pints or quarts of blueberries, examine the entire contents of each sample. When inspecting baskets, take a one-quart sample from each and examine the entire contents. It is difficult to take such a sample without affecting the condition of the product. The recommended procedure is to empty the berries into another basket while setting aside a few ounces at a time; enough to result in a quart sample.

Determining Percentages: All percentages of defects for blueberries are calculated by weight.

It is necessary for inspectors to frequently check the weight of one pint or one quart. In fact, blueberry weights may vary with the crop season, with the sugar content or with the growing region.

The weight of each sample should be entered on the detail sheet in pounds and tenths of a pound while defects for each sample should be entered on the detail sheet by count.

The percentage is determined by evaluating the number of blueberries for each one-tenth (1/10) of a pound. Inspectors should frequently check the number of blueberries in one-tenth (1/10) of a pound with a scale. Usually it takes twice as many white, immature blueberries to weigh the same as well colored mature blueberries.

Foreign material should be accumulated separately throughout the inspection and weighed altogether at the end of the inspection.

Note: The quantities of each defect should be entered by count for each sample. A conversion should be made of the totals of each defect into pounds and tenths of a pound and then into percentages. The foreign material which includes green berries, must be gathered during the entire inspection and weighed at the end and then entered as a total weight. (See above example.)

Example of Calculation:

80 Blueberries = 1/10 lb.
39 blueberries = x
x = 39 ÷ (80 x 10)
= 39 ÷ 800
= .048

and 11.2 lb. = 100%
0.048 lb. = x
x = (.048 x 100%) ÷ 11.2
= 4.8% ÷ 11.2
= 0.428%
= less than 1/2%

Fairly Uniform Size: Blueberries must be fairly uniform in size. This means that variation in size is not sufficient to materially affect the general appearance of the lot. There must be many small berries present to materially affect the appearance (extra large blueberries do not affect the appearance). Without many extra small blueberries present, the lot would always be considered as fairly uniform in size. A measure of leniency is permissible when inspecting for size.

Well Form: You will rarely find misshapen berries, but if the characteristic shape is not there, this defect should be scored as misshapen.

Well Colored: The acceptable characteristic colors of blueberries might be bluish-purple, purple, or bluish-black. A red berry does not meet the color requirement.

To be well colored, 90% of the berries must have the acceptable characteristic color of blueberries when mature. The inspector must score the white or red berries for each container and add them on his detail sheet, but he should mention "poorly colored "berries on the face of his certificate only if the percentage exceeds 10%.

Under the item color use the term well colored or use a general term with well colored followed by a percentage of poorly colored if exceeding 10%,

Example: Mostly well colored, average 20% poorly colored.

A bloom is a white frosty film on the surface of the blueberry and is advantageous but not compulsory. The surface of the berry must have a uniform color. If part of it is discolored, it should be scored as poorly colored.

If the applicant requests that lack of uniformity of color be shown on the certificate, the inspector is permitted to show it under the item color only if more than 10% of the blueberries are poorly colored. Otherwise, it should be shown under the Condition heading with the mention: (not affecting grade).

Note: Green berries are not poorly colored berries but as per our regulations they are considered foreign material. They should be gathered during the entire inspection to be weighed with the other foreign material at the end of the inspection.

Foreign Material: The following are considered foreign material: green berries, leaves, stems, dirt, others.

Insects and Insect Larva:According to the regulations, blueberries must be apparently free from insects and insect larva. This means that the inspector shall do a visual inspection of the lot based on the same inspection procedures described in other parts of this manual.

  • If blueberries are found with insects or insect larva, this will be considered as defects. All defective blueberries will be reported and scored under the three percent general tolerance. If less than three percent defects are found, then the certificate can be issued.
  • If blueberry maggot is found in a lot which otherwise meets the general grade requirements, hold the certificate and refer this lot to Plant Health for further instructions.

Insect Injury: Any berry affected by an insect bite or insect injury is considered as damaged and should be scored against the general tolerance.

Firmness: The requirements of the grade are that blueberries be well formed, sound and free from defects that materially affect their appearance. We will consider a shriveled or soft berry a defect.

Soft: Blueberries which are over mature may be deformed or flattened in a container from the weight of fruit above them indicating they are soft or will remain flattened after light pressure is applied between the fingers which also indicates softness.

Shriveling: Do not score a wilted blueberry as a defect except if the skin is wrinkled.

Decay and Mould: The main condition defect in blueberries is decay. It should always be reported. Do not mix up split or crushed blueberries with decayed berries. Decay implies breakdown of tissues.

At destination, it is sometimes not possible to separate split or crushed blueberries from decayed berries. Under these circumstances, it is permissible to group them together as per the following: Crushed, leaking and/or decayed berries average ...%.

Mould often accompanies decayed blueberries. Mould should always be reported on the face of the certificate in general terms to indicate the portion affected within a container and the location of the affected containers within the car or lot.

Example: Blueberries firm and ripe. At front of vehicle, few trays show 1 to 5 pints, mostly 2 to 3 partially affected on top with white mould. Average 2% decay.

Crushed:  Blueberries with broken skins are scored as crushed berries. When the tissues are discolored without any breakdown, the blueberries should still be scored as crushed, and not as decay. If they are leaking, this should be reported.

Example: Crushed berries average 2% mostly in a leaking condition causing a few other berries to be wet and sticky.

Wet and Sticky: You should score as wet and sticky only those blueberries which are affected by the juice of the leaking blueberries. A wet blueberry caused by condensation or dew is still considered as dry and should not be scored. This is a normal condition. Wet and sticky blueberries are scored against the general tolerance of 3%.

Freezing Injury - Blueberries are a product that can be easily frozen for conservation but fresh blueberries affected by freezing can hardly be preserved and lose their commercial value.

Blueberries affected by freezing lose their firmness and will have a dull appearance. The skin will yield easily to slight pressure and the berries are subject to decay. If no breakdown of tissues occurs, they must be scored as soft and dull in appearance. This defect also applies against the 3% general tolerance.

Any noted breakdown of tissues should be scored as decay. Evidence of ice crystals should be reported.


Blueberry tolerances are applies by weight:

Decay ...................................1%
Foreign material .....................1% / 3% Total
Grade defects ........................3%

Special Tolerance:

Poorly Coloured Berries 10%