L-cystine
L-cystine carries a source-backed screening score of 3/5 and appears in 19 indexed US food products.
Source-backed answer
L-cystine appears in 19 catalogued products. CSPI has no rating attached in this snapshot. Its FDA SAFFA status is “Approved.” Those source labels describe the ingredient; they do not establish whether a particular product, dose, allergy, or diet is safe.
- 19
- catalogued products
- #9,730
- usage rank of 247,206
- 12
- named brands represented
- 65%
- average depth down ingredient lists
Catalog prevalence comes from Open Food Facts ingredient lists. FDA SAFFA and CSPI Chemical Cuisine labels are shown only when the source record contains them.
L-cystine sits in the busiest tenth of the catalog (#9,730 / 247,206)
- Usage rank
- #9,730
- of 247,206 ingredients that appear in at least one catalogued product, tied with 368 others that also appear in exactly 19 products.
- Typical depth in an ingredient list
- 65%
- Averaged label depth puts L-cystine in the lower half of the list (65% of list length, mean slot 29.2). Compound ingredients and OCR noise mean this cannot stand in for quantity.
Ranks use Open Food Facts ingredient rows on this site’s refresh cycle. 247,206 ingredients with ≥1 product appearance enter the ranking. Prevalence and list depth are catalog facts, not toxicology.
Reading this ingredient record
Separate this ingredient from its product neighborhood
This is a mixed product neighborhood: 9 of 19 records have some flagged component, while the rest do not. Compare Charro beans; Chicken Bacon Ranch Wrap; Compleat Pediatric Standard Vanilla to see how surrounding formulations change; do not assign their 80–100 score range to L-cystine itself. The ingredient most often sits in the lower half of the list, and Baby-formula supplies the most useful like-for-like starting point for a label review.
9 of 19 linked records have some flagged component
All 19 NOVA-classified records cluster most heavily in Group 4, while the first-category labels split across several shelves. That makes the 80–100 score spread more informative than the average alone: investigate the low end, identify the actual flagged row, and compare it with a similar unflagged formulation before drawing a conclusion.
Next check: pair one flagged product with a similar unflagged product from the same shelf category.
Function
DOUGH STRENGTHENER, FLAVOR ENHANCER, FLAVORING AGENT OR ADJUVANT, NUTRIENT SUPPLEMENT
How do the sampled products compare?
Each point is one of the 16 sampled products listed below: its overall safety score against how many separately flagged ingredients its label carries. Bubble size is the number of ingredient rows the label actually resolved to.
Safety score vs. flagged-ingredient count for products containing L-cystine
Products Containing L-cystine
16 busy labels from the 19 indexed products that list L-cystine:
High-volume peers for L-cystine
High-volume peers for L-cystine: 19 products, mean screening score 95.8/100. Axes below stay distinct so count-neighbors do not duplicate score-neighbors.
Similar mean product score
Nearest other ingredients by mean product screening score (floored at ≥50 scored products), distinct from the count row.
Using the L-cystine evidence
Use the 19-product footprint and source labels as a starting point, then inspect the records most relevant to your question.
- Review the sampled product records that list L-cystine to see how the ingredient appears in actual labels. Open product sample
- Browse another ingredient record and keep the same FDA/CSPI and prevalence fields in view. Compare a peer
- Read how PlainFoodSafe joins source records before treating a screening label as a personal food or health conclusion. Open methodology
This page describes published source classifications and product-label coverage. It is not dietary, allergy, or medical advice.
L-cystine — common follow-ups
Does L-cystine carry its own safety label in this catalog? ▼
This is a mixed neighborhood: some linked products carry a separate flag while others do not. L-cystine itself carries and FDA SAFFA status "Approved" where the source record supplies them. Compare like-for-like products before treating the average screening score as an ingredient verdict.
Which product shelves show up most often with L-cystine? ▼
L-cystine ranks in the top decile by product count (#9,730 of 247,206), appearing in 19 indexed products led by Baby-formula. The sample list below is a slice of that footprint, not the full universe.
What does L-cystine do in food? ▼
L-cystine is recorded as a dough strengthener, flavor enhancer, flavoring agent or adjuvant, nutrient supplement in source technical-effect fields.
Regulatory status: FDA SAFFA (L-cystine). Safety ratings: CSPI Chemical Cuisine; product presence: Open Food Facts via PlainFoodSafe (September 2026). Figures are computed from those sources, no editor-typed counts. Methodology · State regulations.