How to verify meat yield claims for low-temperature cooking

The fact that the meat is heavier after roasting does not alone prove that this cooking method reduces losses. What restaurants need to compare is how much weight of similar ingredients can be safely sold according to established specifications after a complete process. Stopping the weighing at the moment it comes out of the oven, or weighing the juice, marinade and meat pieces together, may result in a ratio that is beautiful but cannot be used for stocking.

When Alto-Shaam introduced the cooking holding oven, it cited reduced meat shrinkage as a selling point of the equipment. [1] This raises a question worthy of verification for buyers, but it is not the result that Fengzhida equipment or any store has achieved. The following discussion of a store-proven design that can be recalculated does not recommend an unverified low-temperature program or predict which device will win.

Let’s first explain what kind of weight we are weighing.

It is recommended to separate the four nodes. The weight of the purchased raw materials is recorded as A, and the packaging has been removed but has not yet been trimmed; the net weight after trimming and pre-agreed processing and ready to be put into the equipment is recorded as B; the weight of the out-of-machine meat pieces obtained according to the agreed resting and draining methods is recorded as C; the salable weight after being insulated, cut and completed with safety and delivery determination is recorded as D. Each symbol corresponds to a real weighing and cannot be estimated by relying on the previous step.

The pre-processing yield is B divided by A; the cooking weight retention rate is C divided by B; the salable retention rate after leaving the machine is D divided by C; the total yield from purchase to salable is D divided by A. Four items are multiplied by 100% to express percentage. If "cooking shrinkage" is used, this article defines it as the difference between B minus C divided by B. This is only the proportion of net weight loss within the agreed weighing boundaries, and is not equal to the proportion of water loss in muscle tissue alone.

Pickling makes this definition sensitive. If one group absorbs more marinade, B itself increases, and the subsequent weight cannot all be attributed to the heating method. When comparing, the raw material parts, thawing status, trimming specifications and pickling operations should be unified, and the added liquid, remaining liquid and processing time should be recorded. When studying the marinating plan itself, list it as an independent variable. You cannot change the marinade and oven at the same time, and attribute the change only to the equipment.

Whether the juice is available for sale must also be agreed in advance. When weighing out of the pan, the free liquid in the tray should not be included in the weight of the meat; if the juice is used as a sauce, it must be measured as a separate output after applicable safety and use judgments. It can have value in a cost analysis, but it cannot creep into "meat yield" or another reviewer will get a different answer.

How to read a hypothetical weighing account

The following numbers are for demonstration calculations only and are not customer testing. Suppose two groups purchase 10 kilograms of meat each. After trimming according to the same standards, 9 kilograms of meat each enter the machine without adding additional liquid. The current process produces 6.8 kilograms of processed meat, and the candidate process produces 7.2 kilograms. After the insulation and cutting are completed, the current process can sell 6.3 kilograms, and the candidate process can sell 6.6 kilograms.

The cooking shrinkage rate of the current process is 2.2 divided by nine, which is about 24.4 percent; the candidate process is 1.8 divided by nine, which is equal to 20 percent. The difference between the two is about 4.4 percentage points, rather than simply written as "a decrease of 4.4%." The total salable yields were 63% and 66% respectively, and the actual salable difference was 0.3 kilograms. The 0.4 kilogram difference when the machine was shipped was not fully retained at the point of sale.

Let’s look at the mass balance. The current group starts from ten kilograms, trimming removes one kilogram, the net reduction is 2.2 kilograms during the cooking stage, the net reduction is 0.5 kilograms after leaving the machine, and finally 6.3 kilograms, the total is still ten kilograms. The corresponding candidate set is ten equals one plus one point eight plus zero point six plus six point six. The "net reduction" here includes evaporation and losses that are not measured separately and cannot be passed off as the weight of waste that has been collected.

If the weighing account cannot be closed, first look for missing nodes, double entries, container tares, or transcription errors. Don't fill in "evaporation" backwards just to make the equation work. The unexplained differences can be listed separately as unallocated differences; when the differences are large enough to affect the comparison between the two groups, this test can only be used for troubleshooting methods and cannot be used to draw conclusions about the quality of the equipment.

Arrange comparisons into experiments that can be carried out in the kitchen

The person in charge of the experiment first locks in a specific dish and delivery status, and then the weighing personnel randomly assign raw materials of the same batch and similar specifications to two groups. Record individual weights, not just total group weights, so you can find that a certain group happens to get more chunks of meat. If it must be run across days, the sequence can be arranged alternately on multiple dates, and the raw material batches and dates can be recorded to avoid taking the raw material differences on a certain day as a process rule.

Use a scale with the same suitable range for weighing, and first check the equipment status and tare operation. Number the receiving tray, fix the resting time and draining method, and return to the original food processing process immediately after weighing. Weighing hot, waiting for long periods of time, or handling repeatedly will alter readings and may disrupt food handling conditions; weighing arrangements must comply with confirmed health and safety procedures and do not prolong exposure just to get a number.

The record sheet should be re-calculated by someone who is not present. Each node writes gross weight, tare weight and net weight at the same time, indicating the weighing time, scale identification information and operator; retain the original value and reason when modifying the numbers. A summary table that only says "This time the yield is higher" cannot reveal whether the remaining juice at the bottom of the plate was counted twice, nor can it be judged whether the tasting sample has been removed between the two weighings. The sampling weight should be stated from the corresponding node, and do not wait until the end to make up the information based on impressions.

The difference should also be compared with the size of the measurement uncertainty. If the indexing, repeated weighing fluctuations or drain differences are shown to be close to the difference between the two groups, retaining more decimals will not increase the credibility. You can first check the consistency of the weighing method without affecting food processing, and use appropriate measuring tools if necessary. It is an acceptable result without clear advantages and disadvantages, and accidental changes in the last digit of the reading cannot be written as a stable advantage.

The current group and the candidate group do not necessarily use the same heating time because the processes being compared are inherently different. But both sides have to meet their own proven safety requirements, as well as target maturity and delivery quality of the same menu. If the candidate group is heavier simply because it is less cooked, this is not an efficiency advantage. Records should be kept of equipment setup, actual loading, door opening, malfunctions and human intervention to facilitate interpretation of abnormal batches.

Blind codes can reduce the bias caused by evaluators knowing the name of the device, but the order of use cannot be reversed. The person in charge of food safety first checks the raw materials, processing procedures and necessary measurements to confirm that the samples are in edible conditions, and then organizes sensory evaluation. Unreleased samples are not allowed to be tasted; normal appearance and smell cannot replace safety judgment. The World Health Organization lists thorough cooking and storage at safe temperatures as basic principles of food safety. [2]

When the results are not pretty, it is even more important to keep the original records

Samples that fail to meet sensory requirements, are shredded, exceed the holding conditions, or are subject to interruption will be recorded. You can list their reasons separately, but you can't just pick out the successful batches and calculate the average yield. For a whole batch that cannot be sold, the actual salable quantity should be recorded truthfully; if the measurement record is damaged and the weight cannot be judged, it will be marked as missing instead of filling in directly with zero or the group average.

Some of the differences come from handling rather than equipment. For example, the candidate process requires a more accurate loading thickness, and the first overload results in failure; this not only indicates the failure of this run, but also indicates the implementation conditions. The retest should state what adjustments were made and retain the first run. Treating a revised successful outcome as if it had never failed underestimates the management requirements of the new process.

After several rounds of results come out, first look at the salable weight and fluctuations of each batch, and then discuss the purchase cost. The yield advantage only makes sense in economic evaluation when the corresponding dishes continue to occur, the delivery quality is consistent, and the additional labor and energy have been taken into account. The extra 300 grams at one time cannot be multiplied by the entire meat purchase for the whole year. Suitability should be re-examined when changes occur in different parts, bone-in ratios, supplier handling methods and holding times.

The final conclusion that is useful to the purchaser should be a limited and specific sentence: under the listed raw materials, loading, processing and delivery conditions, which batches meet the requirements, what is the salable yield distribution, and what anomalies have not yet been explained. Such a result may support continuing the trial, or it may deny the reason for purchasing; both answers are more valuable than writing a "loss saving" in advance.

References

• Alto-Shaam What is a Cook and Hold Oven
• World Health Organization Five keys to safer food manual