200 kg Surplus Tomatoes with Two Days to Spoilage
A vegetable supplier delivers 200 kg of ripe tomatoes to your small catering unit on Friday afternoon. The tomatoes are at peak ripeness and the supplier will not accept returns. You have two days before significant spoilage, three staff, a chest freezer at -18°C, a six-tray dehydrator, a pH meter, vacuum bags, a gas hob and 20 L of white vinegar. There is no blast freezer. Your customers are hotels that expect consistent colour and flavour, and one buyer has asked for sun-dried tomatoes in oil. The unit's food safety plan requires a documented CCP for any dried or oil-packed product and allergen labelling for sulphites. You have 200 kg, not 20 kg, and cannot buy more equipment.
1. Allocate the 200 kg among at least three preservation methods and justify the split using quality, safety and capacity. Include a decision on the oil-packed request.
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A practical split is:
- 100 kg frozen: Wash, remove stems, halve or chop, pack in 2 kg vacuum bags and freeze at -18°C. Freezing is the fastest way to move volume and preserves colour better than slow drying. It will soften texture, so use it for sauces, stews and soups, not garnish.
- 60 kg dehydrated: Slice uniformly, load six trays without crowding, and dry at 57–60°C until leathery, not brittle. This gives a premium product for hotel buyers. Capacity is the limit, so one or two batches is realistic.
- 30 kg processed into acidified tomato sauce or paste: Cook down with vinegar to pH below 4.6, hot-fill into clean jars, and refrigerate. This uses the hob and gives a shelf-stable acid product if the pH is verified.
- 10 kg fresh: Use within two days for current service.
The oil-packed request should be declined unless the product is acidified to pH 4.6 or below, properly dried, packed with oil and kept refrigerated. Oil packing of inadequately acidified tomatoes creates a botulism risk because the oil excludes oxygen. If the buyer cannot guarantee refrigerated storage, offer the acidified sauce or plain dried tomatoes instead.
2. Specify the critical control points and limits for the dehydrated tomatoes and for the oil-packed product if you agree to make it.
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For dehydrated tomatoes:
- CCP 1 - Drying time/temperature: 57–60°C for the required time, with tray rotation. The operational limit is a final texture and moisture/water activity target agreed in the food safety plan; do not rely on time alone. Verify by checking the heaviest pieces and recording tray position.
- CCP 2 - Post-drying protection: Cool in a clean, dry area away from raw food; pack immediately into clean, dry containers. Reject any batch with condensation or mould.
- Allergen control: If sulphites are used, record the concentration and label. Many buyers reject sulphites, so using them should be a commercial decision.
For oil-packed tomatoes, add:
- CCP - Acidification: Every batch must be checked with a calibrated pH meter and reach pH 4.6 or below before packing. Record the reading.
- CCP - Heat treatment and storage: Use a documented heat process, then keep the product refrigerated. Oil-packed products must not be stored at ambient temperature unless the process has been validated.
- Verification: Retain a sample, check pH meter calibration, and review records weekly.
3. Calculate the approximate yield and label requirements, and explain one quality defect you would expect from the freezer method.
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Tomatoes are roughly 94–95% water, so drying removes most of the weight. A realistic dried yield is about 5–8 kg from 60 kg fresh, depending on variety and final moisture. If the unit aims for a leathery product at about 15–20% moisture, 7 kg is a reasonable planning figure. The acidified sauce will yield less than the 30 kg input because water is cooked off; expect about 15–18 kg of sauce.
Labels should include: product name; ingredients in descending order; net weight; date of production and best-before date; storage instructions; batch code; and the unit's name and address. If sulphites are used above the labelling threshold, declare them clearly. Oil-packed jars must say keep refrigerated, and acidified sauce should state the same once opened.
One expected freezer defect is texture collapse: ice crystals rupture cell walls, so the thawed tomatoes release water and become soft. That is acceptable in sauce but not for a salad garnish. To limit it, freeze quickly in thin layers or use vacuum bags, and thaw in the refrigerator, not at room temperature.