Stem and Leaf Control in IQF Blackcurrant Specifications

Name the product and the material

Blackcurrants in a blue liner. The product form and the agreed examination basis should accompany a cleanliness result.

Identify the ingredient as blackcurrants, Ribes nigrum, and describe the supplied form. Whole loose berries, deliberately retained clusters and crushed material present different inspection problems. A report for one form cannot automatically establish the condition of another. State the intended application and where any further cleaning, screening or processing is expected to occur.

The USDA standard for currants for processing, effective September 2016, illustrates why scope matters. Its U.S. No. 1 description concerns currants that have not been separated from their stems. Its grading provisions use a bunch basis, with a separate weight treatment for loose berries. This voluntary standard is not automatically a specification for commercially de-stemmed IQF blackcurrants; its defect tolerances should not be copied into that purchase requirement.

Published commercial documents also use different structures. Foodnet’s January 2020 blackcurrant specification gives stems and leaves separate mass-based rows. Foodcom’s blackcurrant product page describes stalks and plant debris using counts against a product mass. These are examples of individual suppliers’ descriptions, not common industry allowances or XMG commitments. Their different units are a reason to request a comparable inspection basis.

Do not make “extraneous vegetable matter,” often shortened to EVM, the only definition in the agreement. One document may use it for material from the blackcurrant plant; another may split own-plant material, other plant material and non-plant objects into separate groups. Read the actual definitions rather than assuming that the same abbreviation means the same thing everywhere.

The category names should support the intended decision. Own-plant stems and leaves can be commercial cleanliness defects, but botanical origin is not a general safety clearance. An unidentified object should retain its own identity and review status until assessed. It should not disappear into a small total EVM percentage simply because the aggregate number looks favourable.

Keep fruit-condition defects separate where the specification requires them. Split berries, damaged fruit and clumps may affect the application, but they are different observations from a loose stem. Combining them into one unexplained “defect percentage” makes it difficult to identify which requirement failed or what follow-up would address it.

Separate attached stalks, loose stems and leaves

Blackcurrants on the plant show supporting stalks, berry ends and leaves. This botanical context helps distinguish the structures named in a specification.

Blackcurrants grow with supporting stalks and foliage. The RHS growing guide calls a bunch a strig and describes removing berries from stems after harvesting suitable bunches. That botanical context helps explain the material names; it does not prescribe the cleaning process for a frozen-food factory.

Agree a working definition of an attached stalk: for example, a stalk still physically connected to a berry at the time of examination. Record that state before pulling it off. If an inspector first removes every stalk and then counts only loose material, the report loses the distinction the buyer may need. The same item must not silently become two findings because its condition was changed during inspection.

A loose stem is a detached piece observed among the product. The specification should say whether small stalks and larger woody pieces belong in one category or separate categories, and how any size boundary is applied. Define what happens at the boundary itself. “Short” and “long” can support a conversation, but they do not produce a reproducible classification without a shared reference.

Leaves need their own counting convention. Does a leaf fragment count as one item, or does the method assess recovered leaf mass? If one leaf has already broken into several separate pieces, do not reconstruct an imagined original leaf count unless the agreed method specifically requires and supports that approach. Describe the pieces that were actually observed.

The Kwantlen Polytechnic University plant database describes blackcurrants as having a persistent calyx. Retained flower-end material is therefore not simply another name for the supporting stalk. Include a clear photograph and state how that feature is treated in the buyer’s specification. Its botanical name alone neither makes it a contractual defect nor settles its acceptance.

The following categories are an illustrative working structure for discussion. They need agreement for the actual product and method.

Choose units that answer the specification

Conceptual count-versus-mass comparison. The three illustrated stalks are not an inspection result or sample-size recommendation, and the blank balance supplies no measured mass.

A piece count and a mass percentage answer different questions. Count records how many defined items were found; mass records how much the defined recovered material weighs relative to a stated quantity. Numerous fine stalks and one heavier stem can produce very different count and mass relationships. There is no reliable conversion between the two without the relevant measurements.

Projuice’s January 2021 blackcurrant specification illustrates the need to read each row: its physical-characteristic table uses both piece counts and mass percentages, with different examination quantities. The useful lesson is to retain the definition, unit and denominator together. Neither that document’s categories nor its numerical allowances should become a default for another order.

Consider a hypothetical calculation, not an acceptance example. Five loose stems are found in an examined 2.000 kg sample. The observed count is five; the normalised result is 2.5 pieces per kilogram. Reporting 2.5 does not mean half a stem was observed. Keep the raw count and examined mass alongside the normalised value so another reviewer can reproduce the arithmetic.

Attached stalks create a second question: what is being weighed? In another fictional 2,000 g sample, the berries carrying stalks weigh 24 g in total. If the method defines the defect as affected fruit, that observation is 1.2% of sample mass. If the stalks are then separately removed and weigh 0.4 g, their stalk-only mass is 0.02% of the same original sample mass. Both calculations can be arithmetically correct while describing different things.

Do not choose whichever of those values looks smaller and label it “stems.” Name the numerator: affected berry mass, recovered stalk mass or number of affected berries. Also record whether loose stems are included in that numerator. The buyer needs the agreed result, not a mathematically valid answer to an unasked question.

Define the sample condition used for weighing. As-received frozen mass, a prepared sample and drained product can have different bases. If the method calls for thawing, draining or separation, record that preparation and the denominator it requires. Do not silently divide a recovered dry-looking item mass by a different product basis from the one in the specification.

For small recovered masses, use equipment and handling appropriate to the required measurement. Record the balance resolution, tare treatment and any difficulty recovering wet material cleanly. A displayed zero is not proof that no material exists below the equipment’s useful resolution. Preserve the observation and obtain technical clarification when the required precision exceeds what the method can support.

Examine the sample before altering it

Illustrative sample-handling concept, not photographs of a measured transfer. Keep the selected contents in the examination, including recovered plant material; no sample quantity or preparation protocol is prescribed.

The receiving inspection should start from the sample selected under the agreed plan. Identify its lot, selected packages, collection locations, collection time and handling. A neatly arranged handful taken for a sales photograph has a different purpose from a receiving sample. Calling both of them “the sample” conceals an important difference.

Do not pick out visible stems, brush away leaves or rinse the fruit before recording the cleanliness observations, unless that treatment is explicitly part of the agreed examination method. Such preparation can change both the recovered material and the product mass. A cleaned sample may be useful for an application trial, but it cannot stand in for the unaltered receiving observation.

When transferring the selected product to an examination surface, keep track of everything that belongs to that portion. Material can remain in folds of the liner or cling to a bag. Record how the transfer was performed and any unrecovered material or handling loss. A method intended to assess the contents needs to explain the treatment of those retained pieces rather than overlooking them.

Spread and inspect the product in a way suitable for the agreed examination. Record any preparation needed to make attached material visible, including whether berries remained frozen or were thawed under defined conditions. The article’s illustrations do not specify a temperature or duration for this step. The responsible technical team should establish the method and relevant handling controls.

Keep package-level observations when they may affect interpretation. A total count can hide a concentration in one selected pack. The pattern does not prove a cause, but it can guide questions about packing time, material distribution or a cleaning step. Retain the individual findings even if the agreed report also requires a combined result.

Distinguish planned sampling from investigative collection. A package selected because someone saw a stem is useful evidence of that observation; it is not interchangeable with a package selected without that trigger. Preserve both records and their purposes. An apparently favourable average should not erase a separately identified object requiring assessment.

At the end of the examination, state the quantity actually inspected. If only part of a delivered sample was used, do not report its full labelled weight as examined. A no-finding result should describe the selected material and method; it does not establish that every berry in the commercial lot is free from the defined items.

Use photographs to agree borderline findings

Illustrative classification examples with no common scale or acceptance boundary. Actual reference photographs and definitions should show how attached stalks, loose stems and leaf material are recorded.

Photographs are most useful when they resolve a particular classification question. Show an attached stalk while it is still attached, a loose stem as recovered and leaf material in its observed condition. Keep a wider contextual image as well as a close view where needed. A close-up alone may hide whether the item belonged to the sample or was introduced during handling.

For any size-based category, use a suitable readable scale and record the measurement method. A photograph resized for a presentation is not itself a fixed-size reference. Preserve the original image and its sample identity, and explain whether the required dimension was measured directly or from an appropriate calibrated image. Do not infer an exact length from a casual photograph.

Use the same named examples when aligning two inspectors. Ask each to classify them independently, then review disagreements against the written definitions. If one person treats attached stalks as affected berries and the other records only stalk mass, better photographs alone will not solve the problem. The measurement instruction must change or become clearer.

Include borderline observations in the discussion. A short attached stalk, a broken stem, a folded leaf piece and uncertain flower-end material can reveal ambiguities that a perfect reference berry does not. Keep uncertain identity separate from a confirmed category. Do not force every brown or green mark into a defect class merely to complete the table.

A photo guide can show classification examples without making them acceptance limits. Label illustrative diagrams as such, and label actual reference images with the relevant identity and scope. If a buyer approves a photograph, record what that approval means: category identification, visual appearance or another specified purpose. It does not automatically approve all material outside the frame.

Version the photo guide with the written specification. When a definition changes, identify which examples need review and which lots or orders the change affects. Keeping an old image beside a newly worded clause can recreate the same disagreement during receiving inspection. Both sides should be able to identify the instruction actually used for the reported result.

Write an acceptance clause that can be used

The final clause needs more than a material name followed by a number. Identify the product form, each category, its limit and unit, the sample-selection and examination method, the calculation rule and the action required for an unresolved or nonconforming finding. Include any applicable market requirements separately from commercial cleanliness allowances.

For attached stalks, specify whether the acceptance calculation uses affected berries, stalk pieces or recovered stalk mass. For loose stems, identify any size categories and how pieces at the boundary are assigned. For leaves, state how fragments are counted or weighed. If more than one measurement is required, name the result that controls each decision.

Describe what a stated absence requirement means operationally. It needs a defined category, examined quantity, method and decision rule. It should not be transformed into an unsupported guarantee about every unit in the lot. Likewise, a supplier’s published wording that refers to a sample is not enough to reconstruct the full plan without further information.

Agree the treatment of uncertain and potentially hazardous material before routine receiving work. The responsible team may need identification, retained evidence and a separate assessment. A contractual allowance for leaves should not be used to accept an unidentified non-plant object. Keep the observation, product status and required follow-up connected.

For a beverage or jam application, request evidence for any proposed downstream removal step. A screen description or a statement that the fruit will be processed does not establish the removal of every attached stalk or flexible leaf piece. Confirm the actual application, equipment and evidence needed to assess that proposal. Do not replace the receiving requirement with an unverified assumption about later processing.

The finished report should identify the specification and photo-guide versions, actual sample basis, category results and decision. If the parties agree a change after reviewing a finding, retain the original result and document the new decision separately. This keeps a useful account of the supplied material and prevents a revised label from disguising what was originally observed.

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