L-cysteine Monohydrochloride

L-cysteine Monohydrochloride carries a safety score of 3/5 and appears in 108 indexed US food products.

Safety score 60.0%

3/5 from FDA SAFFA + CSPI Chemical Cuisine

How common is vs other flagged additives?

Number of indexed products containing each of the most common flagged additives — L-cysteine Monohydrochloride highlighted.

Indexed products containing each flagged additive. Source: Open Food Facts ingredient lists × FDA SAFFA × CSPI Chemical Cuisine.

Caramel Coloring22612Red 4021595Yellow 518987Carrageenan17853Blue 116643Yellow 613560Sucralose10490L-cysteine Monohydrochloride108
Indexed products containing each flagged additive. Source: Open Food Facts ingredient lists × FDA SAFFA × CSPI Chemical Cuisine.
FDA Status
GRAS
Safety Score
3/5

Function

DOUGH STRENGTHENER, FLAVOR ENHANCER, FLAVORING AGENT OR ADJUVANT, FLOUR TREATING AGENT, LEAVENING AGENT, NUTRIENT SUPPLEMENT

Safety Assessment

L-cysteine Monohydrochloride has a moderate safety profile (3/5). While approved for use, some studies or consumer advocacy groups have raised questions about certain aspects of this ingredient. Consumers who prefer caution may wish to limit intake.

What the Data Says About

L-cysteine Monohydrochloride currently appears in 108 products across the OpenFoodFacts catalog we index, which gives a concrete measure of its footprint on US grocery shelves. Our internal safety score of 3/5 synthesizes FDA Substances Added to Food (SAFFA) regulatory status — currently "GRAS" — with the Center for Science in the Public Interest (CSPI) Chemical Cuisine classification. These two frameworks capture different questions: regulators ask whether exposure at typical intake is acceptable, while consumer-advocacy groups examine cumulative dietary load and vulnerable-population risk.

In food manufacturing, L-cysteine Monohydrochloride functions as a dough strengthener, flavor enhancer, flavoring agent or adjuvant, flour treating agent, leavening agent, nutrient supplement. That technical role explains why it recurs across many product categories — formulators select specific additives for stability, shelf life, color, or texture performance, and substitution is rarely a one-for-one swap when regulations or consumer preferences shift. Inspection and outbreak data often trace back to breakdown in the control of exactly these kinds of functional ingredients, either through contaminated batches, undisclosed substitutions, or labeling errors that trigger FDA-initiated recalls.

No specific concern flags are attached to L-cysteine Monohydrochloride in our current data snapshot beyond the regulatory and CSPI classifications above. That does not rule out individual sensitivity reactions, and anyone managing allergies, elimination diets, or chronic conditions should verify with a qualified healthcare professional before relying on population-level ratings.

Safety Profile at a Glance

Regulatory and safety classifications for L-cysteine Monohydrochloride
Source Classification Year
FDA SAFFA GRAS 2024
CSPI Chemical Cuisine Not rated 2024
PlainFoodSafe Score 3/5 2026
Product footprint 108 products OpenFoodFacts

FDA SAFFA database, CSPI Chemical Cuisine ratings, OpenFoodFacts product index. See methodology.

Products Containing

Showing 50 of 108 products

Authentic 8 Flour Tortillas
Unknown
100/100
Bell's, traditional stuffing
Bell's
100/100
Breakfast burrito
Unknown
95/100
Buddies chicken breast nuggets
Unknown
100/100
Burrito style 9" authentic flour tortillas
Unknown
100/100
Casa Mamita Chicken & Cheese Taquitos
Aldi
100/100
Celeste, pizza, mushroom
Celeste
95/100
chi chis 100 calorie fajita style
Unknown
100/100
Chicken & Cheese Mini Taquitos
Meijer
100/100
Chicken breast nuggets
Yummy
100/100
Chicken breast nuggets
Maxi
100/100
Chicken Breast Patties
Yummy
95/100
Chicken frozen taquitos
Unknown
100/100
Chicken Taquitos
Great Value
100/100
Classic white gourmet pub rolls
Unknown
85/100
Cohen's, 10 Seasoned Beef Kreplach
Cohen's Food Llc
100/100
Country white bread
S. Rosen's, Alpha Baking Co. Inc.
85/100
Creme Puffs
Entenmann's
50/100
Crispy poutine bites
Unknown
95/100
Delux Pizza
Celeste
50/100
Dino nuggets dinosaur-shaped chicken breast patty fritters with rib meat
Unknown
100/100
Dinosaur chicken nuggets
Unknown
100/100
Dinosaur-shaped chicken breast patty fritters with rib meat
Unknown
100/100
Dinosaur-shaped chicken breast patty fritters with rib meat
Dino
100/100
Dinosaur-shaped chicken breast patty fritters with rib meat
Unknown
100/100
Everything french bread
Unknown
85/100
Everything Italian Bread
Marketside
85/100
Fajita flour tortillas
Herdez
100/100
Fajita style 8 tortillas
Unknown
100/100
Fajita style 8" authentic flour tortillas
Unknown
100/100
Fajita style 8" authentic whole wheat tortillas
Unknown
100/100
Fajita Style Flour Tortillas
Spartan
100/100
Fajita Style Multi-Grain Tortillas
Chi-Chi's
100/100
Fajita Style Tortillas
Chi-Chi's, Hormel Foods Llc
100/100
Fajita Style Tortillas Flour
Chi-Chi's
100/100
Fajita Style Whole Wheat Tortillas
Spartan
100/100
Flaky Individually Wrapped Pastries
Sara Lee
50/100
Flour tortilla chicken & cheese tacquitos
Jose Ole
100/100
Flour Tortillas
Meijer
100/100
Flour tortillas
Unknown
100/100
Flour tortillas
Unknown
100/100
Flour Tortillas
Weis
100/100
Flour tortillas
Unknown
100/100
Flour tortillas
Unknown
100/100
Flour tortillas
Unknown
100/100
Flour tortillas
Unknown
100/100
Flour tortillas soft taco
Unknown
100/100
French Bread
Marketside
85/100
French Bread
Marketside
85/100
Fresh foods market, tortelloni with italian sausage
Fresh Foods Market
85/100

Frequently Asked Questions

Is L-cysteine Monohydrochloride safe to eat?

L-cysteine Monohydrochloride has a safety score of 3/5. FDA status: GRAS. Always check with a healthcare provider if you have specific dietary concerns.

What products contain L-cysteine Monohydrochloride?

L-cysteine Monohydrochloride is found in 108 products in our database, spanning various food categories and brands.

What does L-cysteine Monohydrochloride do in food?

L-cysteine Monohydrochloride is used as a dough strengthener, flavor enhancer, flavoring agent or adjuvant, flour treating agent, leavening agent, nutrient supplement in food products.

Where does this ingredient safety data come from?

Safety data comes from the FDA's SAFFA (Substances Added to Food) database, CSPI (Center for Science in the Public Interest) ratings, and the OpenFoodFacts product database. Product counts reflect items cataloged in OpenFoodFacts.