| Course | NS305 Food Safety |
|---|---|
| Unit | Unit 4 |
| Paper type | Temperature log analysis |
| Length | About 870 words, 6 pages double-spaced |
| Format | APA 7 student paper |
| School | Purdue University Global |
| Program | BS in Nutrition Science |
| Updated | October 2026 |
Free sample paper for NS305 Unit 4
Four Hours the Record Cannot Explain: A Unit 4 Temperature Log Analysis of One Week in a Cafe's Two Coolers
[Student Name]
Purdue University Global
NS305: Food Safety
Unit 4 Temperature Log Analysis
[Instructor Name]
[Date]
Wabash Street Cafe, its coolers, staff and readings are composite; the Food Code provisions, restaurant cooling study and refrigerator survey cited are real.
To, From, Subject
To: Dana Ruiz, General Manager. From: NS305 student, shift lead. Subject: Cold-holding log, Monday through Sunday, sandwich-line reach-in and walk-in cooler.
The Log on One Page
The log covers two units, the sandwich-line reach-in and the walk-in, checked four times a day at 6:40 a.m., 10:40 a.m., 2:40 p.m. and 6:40 p.m., for fifty-six readings. The attached chart plots both units against a line at 41°F, the Food Code limit for cold holding (U.S. Food and Drug Administration [FDA], 2022). Fifty-five readings sit at or below the line. One sits above it. Findings follow in order of the harm each could cause.
Finding 1: Thursday, 2:40 p.m., 46°F
The sandwich-line reach-in read 39°F at 10:40 a.m. and 46°F at 2:40 p.m. The corrective action column is blank. At 6:40 p.m. it read 40°F, so something was done, but the log does not say what, and it does not say what happened to the food.
The food was last known to be at a safe temperature at 10:40. It was known to be unsafe at 2:40. Somewhere in those four hours it crossed 41°F, and it may have stayed above the line until well after 2:40. The record cannot tell us whether the turkey, ham and cut tomatoes in that unit spent twenty minutes or more than four hours above 41°F.
Because the log shows when the food was last safe but not when it became unsafe, the only defensible assumption is the worst one, that the food was warm for the whole gap, and on that assumption it should have been discarded.
The Food Code allows ready-to-eat food to be held without temperature control for up to four hours, but only under a written time-as-control procedure in which the food is marked and discarded on schedule (FDA, 2022). The cafe has no such procedure for the sandwich line, so the four-hour allowance does not apply. Staff on Thursday recall that a full hotel pan of warm roasted turkey went into the reach-in at about 1:30 to cool. A restaurant cooling study found that many kitchens cool food in deep or covered containers inside units that are also holding cold food, which can warm everything around it (Brown et al., 2012). That is the likely cause. Cooling belongs in the walk-in, in shallow pans, uncovered until cold.
Finding 2: Drift Inside the Limit
The walk-in read 36°F on Monday morning and 40°F by Sunday evening, rising almost every day. Every reading is legal. The trend is not. A walk-in that gains half a degree a day will cross 41°F next week. The likely causes are a door gasket torn near the hinge, found on inspection, and a heavier delivery on Thursday that packed product against the evaporator fan. Action: replace the gasket and keep a hand's width clear in front of the fan.
Finding 3: Entries Too Tidy to Trust
Every 6:40 a.m. reading on the reach-in is exactly 38°F, all seven days, in the same pen. Real readings wobble. Seven identical numbers more likely mean the opener writes a typical value without taking a reading. If that is so, the morning column is worth nothing, and Finding 1 might not be the only excursion. A survey of household refrigerators found that only 11 percent of respondents owned a thermometer for their refrigerator, and those who had used one kept safer temperatures (Kosa et al., 2007); a log works only when the thermometer is actually read.
Finding 4: Air Against Product
Both units are checked with a dial thermometer hanging in the air. Air temperature swings each time the door opens and recovers in minutes; food changes more slowly. A probe reading in a sentinel container, a cup of water or a pan of sliced tomatoes, is closer to what the food experiences. Restaurants that do not calibrate thermometers were common in the cooling study (Brown et al., 2012), and neither of ours has a calibration date.
Recommendations: A Form That Forces an Answer
1. Replace the log with a form whose corrective action column cannot be left blank for any reading above 41°F, with boxes for "food discarded," "food moved" and "time last at 41°F."
2. Take each reading with a calibrated probe in the sentinel container, and record the probe's calibration date weekly.
3. Cool cooked food only in the walk-in, in shallow uncovered pans.
4. Replace the walk-in door gasket this week and recheck the trend.
5. Have the shift lead initial the 6:40 a.m. entries for one month, and compare them with a random spot check.
Limits
One week is a small sample. Staff memory of Thursday is a week old. The analysis cannot recover what was done with the food, and it cannot prove the morning entries were invented, only that they are unlikely to be real.
References
Brown, L. G., Ripley, D., Blade, H., Reimann, D., Everstine, K., Nicholas, D., Egan, J., Koktavy, N., & Quilliam, D. N. (2012). Restaurant food cooling practices. Journal of Food Protection, 75(12), 2172-2178. https://doi.org/10.4315/0362-028X.JFP-12-256
Kosa, K. M., Cates, S. C., Karns, S., Godwin, S. L., & Chambers, D. (2007). Consumer home refrigeration practices: Results of a web-based survey. Journal of Food Protection, 70(7), 1640-1649. https://doi.org/10.4315/0362-028X-70.7.1640
U.S. Food and Drug Administration. (2022). Food Code 2022. U.S. Department of Health and Human Services. https://www.fda.gov/food/fda-food-code/food-code-2022
What the NS305 Unit 4 assignment asks for
The Unit 4 assignment gives students a temperature log, or asks them to collect one, and expects an analysis of what it shows. Prompts usually ask which readings are out of range, what they mean for the food and what should change. Present the log in a form a reader can scan, such as a grid or chart. Order findings by the harm each could cause, not by date. For any out-of-range reading, work out how long the food may have been above the limit. Cite the Food Code limit for cold or hot holding. Look for patterns as well as violations, including drift, gaps and suspicious entries. End with recommendations tied to each finding. Most submissions fit on two to four memo pages.
Inside the NS305 Unit 4 example
The memo is addressed to the general manager and covers seven days for two coolers. A short section describes fifty-six readings plotted against a 41°F line. The first finding is the Thursday reading of 46°F, last known safe at 10:40 that morning. The highlighted sentence explains why the worst case must be assumed. A paragraph on time-as-control explains why the four-hour allowance does not apply without a written procedure. A warm pan of turkey loaded at 1:30 is named as the likely cause. Further findings cover the walk-in's upward drift, seven identical morning entries and thermometers hanging in air. Five numbered recommendations follow, including a form with a mandatory corrective action column. A limits section admits that one week and staff memory cannot settle every question.
Reading the NS305 Unit 4 grading rubric
Unit 4 log analyses are usually graded on accurate reading of the data, correct use of the Food Code limits and the quality of the recommendations. Identifying the out-of-range value is expected; working out how long the food was at risk earns more. Points go to recognizing patterns, such as drift or entries that never vary. Each recommendation should answer a named finding. A clear visual of the log helps the reader. Correct citations and memo format are also assessed. Analyses that only list violations without explaining their meaning often score lower. Explaining why the food should be discarded, with reasoning, is often decisive. Spotting entries that look invented is a common mark of careful reading.
NS305 Unit 4 help: mistakes that cost points
Log analyses often stop at the one reading above 41°F and never ask how long the food was warm. Another weakness is listing every entry in order, which buries the important finding. Some writers miss the trend in readings that stay legal but keep rising. Identical entries are usually accepted without question. Air temperatures are often treated as food temperatures. Recommendations tend to repeat the rule instead of changing the form or the process. Some memos recommend discard without showing why. If you have the log but are unsure what it proves, start from the last reading known to be safe. Our writers can draft the memo from that reading, with the recommendations tied to it.
Get an NS305 Unit 4 example written to your instructions
No two NS305 sections hand out the same Unit 4 week of readings. Upload yours, whether a spreadsheet, a photographed form or a grid inside the instructions, along with the rubric, and a free first custom sample reads those exact numbers within 24-48 hours. It finds the entry that decides what happens to the food and says what the record cannot prove. The paper above is an original model document written by our desk, not a submitted student paper and not an official Purdue University Global document.
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NS305 Unit 4 questions, answered
What if the assigned log has no out-of-range readings?
Then the analysis turns to what the log can and cannot prove. Gaps between checks, readings that never vary, missing initials and air temperatures standing in for food temperatures are all findings, and so is a trend moving toward a limit. A log that looks perfect is often the most interesting one to analyze, because perfection in hand-recorded data is itself unusual.
Which temperature limits should the analysis cite?
The current FDA Food Code sets cold holding at 41F or below and hot holding at 135F or above, and your state may have adopted a particular edition. Name the edition in use and the provision number, and check whether the prompt names a different standard. Where editions or jurisdictions differ, say which limit the analysis applies and why it was chosen.
Should the analysis recommend throwing food away?
When the evidence supports it, yes, and the reasoning should be visible rather than asserted. A discard recommendation turns on how long food may have been above the limit, which the log often cannot show. Where the duration is unknown, the conservative reading treats the food as out of control for the whole interval. State the uncertainty and the cautious choice together.
Where can I find a free NS305 Unit 4 sample paper?
This page has a complete Unit 4 memo analyzing a week of cooler readings, with a 46°F excursion, a drifting walk-in and five recommendations.
How long can cold food be above 41°F before it must be thrown out?
Under a written time-as-control procedure, ready-to-eat food can be held without temperature control for up to four hours and then discarded. Without such a procedure, food found above 41°F for an unknown time should usually be discarded.