CommercialToolry

Learning About Celery Stick: Grades, Material Standards, and Industrial Applications

Types of Celery Sticks: Forms, Uses & Benefits

Celery sticks come in various forms, each tailored to different culinary applications, dietary preferences, and convenience needs. While all types originate from the same crisp, nutrient-rich Apium graveolens plant, their preparation—whether whole, sliced, or creatively shaped—can significantly affect texture, flavor absorption, and usability in recipes.

Understanding the different types of celery sticks helps home cooks, meal preppers, and professional chefs make informed choices for snacks, salads, soups, and gourmet dishes. Below is a detailed breakdown of the most common forms available today.

Fresh Celery Sticks

The classic, go-to form of celery—crisp, juicy, and full of natural flavor.

Advantages
  • Maximum crunch and freshness
  • Highest nutritional retention (vitamins K, C, potassium)
  • Versatile for snacking, dipping, or chopping
  • Long shelf life when stored properly
Limitations
  • Requires washing and cutting if not prepped
  • Outer stalks can be fibrous
  • Takes up more storage space

Best for: Snacking with peanut butter, crudité platters, base for chicken salad

Thinly Sliced Celery Sticks

Celery cut into fine rounds or half-moons for easy integration into cooked or mixed dishes.

Advantages
  • Blends seamlessly into soups, stews, and casseroles
  • Even texture distribution in recipes
  • Common in pre-cut meal prep kits
  • Quick to cook and absorb flavors
Limitations
  • Loses crunch faster than whole sticks
  • Shorter shelf life once cut
  • Less ideal for dipping or finger foods

Best for: Broth-based soups, tuna/chicken salad, stir-fries, stuffing

Celery Hearts

The tender inner stalks of the celery bunch, prized for their delicate texture and milder taste.

Advantages
  • Softer, less fibrous texture
  • Milder, slightly sweeter flavor
  • Perfect for raw applications like salads
  • Often pre-washed and ready to use
Limitations
  • More expensive than whole celery
  • Smaller quantity per package
  • Less crunch compared to outer stalks

Best for: Waldorf salad, green salads, canapés, and refined dishes where texture matters

Cut Celery Sticks

Pre-cut, ready-to-eat celery pieces, typically bite-sized or snack-ready.

Advantages
  • Ultimate convenience for on-the-go eating
  • Common in school lunches, office snacks, and party trays
  • Available in snack packs with dips (e.g., ranch, hummus)
  • Saves prep time in commercial kitchens
Limitations
  • Higher cost per ounce
  • Packaging increases environmental impact
  • May lose crispness faster

Best for: Lunchboxes, catering, healthy vending, quick snacks

Celery Ribbons

Thin, flat strips created by peeling stalks with a vegetable peeler—ideal for modern and elegant presentations.

Advantages
  • Unique, restaurant-quality presentation
  • Excellent for marinating and absorbing dressings
  • Softer bite while retaining freshness
  • Perfect for grain bowls, slaws, and wraps
Limitations
  • Time-consuming to prepare at home
  • Less structural integrity for dipping
  • Limited availability in stores

Best for: Gourmet salads, grain bowls, infused dishes, and decorative garnishes

Type Texture Best Use Convenience Nutritional Value
Fresh Celery Sticks Crisp, crunchy Snacking, salads, dips Medium Excellent
Thinly Sliced Softens when cooked Soups, stews, salads High (if pre-cut) Good
Celery Hearts Tender, mild Salads, refined dishes High Very Good
Cut Celery Sticks Crisp, ready-to-eat Snacking, meal prep Very High Good
Celery Ribbons Delicate, flexible Gourmet dishes, garnishes Low (unless pre-made) Good

Pro Tip: To keep cut celery sticks crisp, store them in a container of cold water in the refrigerator. Change the water every day to maintain freshness for up to a week.

Culinary Insight: For maximum flavor absorption in salads or marinades, use celery ribbons or thinly sliced celery and let them sit in the dressing for 10–15 minutes before serving.

Features of Celery Sticks: A Nutritional and Sensory Breakdown

Celery sticks are far more than just a crunchy snack—they are a powerhouse of hydration, nutrition, and functional benefits. Revered for their refreshing bite and culinary flexibility, celery is a staple in raw diets, soups, stir-fries, and juicing regimens. Below is a detailed exploration of the key features that make celery a standout vegetable in both health and gastronomy.

1. Crunchy Texture – Nature’s Hydrating Crisp

The signature crunch of celery is one of its most beloved qualities. This crispness stems from its exceptionally high water content—approximately 95%—which gives it a juicy, refreshing quality perfect for quenching thirst and satisfying hunger. The structural integrity comes from its fibrous vascular bundles, which resist initial biting force before yielding with a clean snap.

This texture not only enhances sensory enjoyment but also plays a functional role: the act of chewing celery increases saliva production, aiding digestion and oral health. Its satisfying crunch makes it ideal for raw consumption, pairing with dips like peanut butter or hummus, or adding textural contrast to salads, wraps, and vegetable platters.

2. Mild Flavor – The Perfect Culinary Canvas

Celery has a subtly earthy, slightly peppery, and mildly salty taste that doesn’t dominate other ingredients. This neutral flavor profile makes it a versatile component in both raw and cooked dishes. It serves as a foundational ingredient in mirepoix (with onions and carrots), forming the aromatic base of countless soups, stews, and sauces.

Because it doesn’t overpower, celery can be seasoned in various ways—stuffed with cheese, coated in nut butter, or marinated in dressings—making it a favorite for healthy snacking and creative meal prep. Its natural saltiness also makes it a useful low-sodium flavor enhancer in diets requiring reduced salt intake.

3. Low Calorie – A Weight-Conscious Snack Hero

With only about 10 calories per medium stalk, celery is a go-to choice for those managing weight or seeking nutrient-dense, low-energy foods. Often cited as a “negative-calorie” food (though this is debated), celery requires more energy to chew and digest than it provides, contributing to satiety without caloric excess.

Its combination of high water and fiber content helps promote fullness, reducing the likelihood of overeating. This makes celery an excellent addition to weight-loss diets, intermittent fasting routines, or as a replacement for higher-calorie snacks like chips or crackers.

4. High in Fiber – Support for Digestive Wellness

Celery is a good source of dietary fiber, particularly insoluble fiber, which adds bulk to stool and supports regular bowel movements. A single cup of chopped celery provides about 1.6 grams of fiber, contributing to daily recommendations (25–38 grams).

The fibrous strands in celery stimulate thorough chewing, which slows eating and supports mindful consumption. Once ingested, the fiber aids in maintaining gut motility, preventing constipation, and nurturing a healthy gut microbiome. Regular intake may also help regulate blood sugar levels by slowing glucose absorption.

5. Nutrient-Rich – Packed with Vitamins and Antioxidants

Despite its low calorie count, celery is surprisingly rich in essential nutrients. Key vitamins and minerals include:

Nutrient Amount per 1 Cup (100g) Health Benefits
Vitamin K 30–40% of RDI Supports blood clotting and bone health
Vitamin C 5–10% of RDI Boosts immune function and acts as an antioxidant
Potassium 8–10% of RDI Regulates blood pressure and supports heart function
Folate (Vitamin B9) 5% of RDI Essential for cell division and DNA synthesis
Phthalides (Antioxidants) Naturally occurring May help lower blood pressure and reduce inflammation

Celery also contains flavonoids and polyphenolic compounds that combat oxidative stress and may reduce the risk of chronic diseases such as heart disease and certain cancers. These antioxidants help neutralize free radicals, protecting cells from damage and supporting long-term wellness.

Health Benefits Summary

  • Hydration Support: 95% water content helps maintain fluid balance.
  • Digestive Health: Fiber promotes regularity and gut motility.
  • Heart Health: Potassium and phthalides may help regulate blood pressure.
  • Anti-Inflammatory: Antioxidants reduce oxidative stress and inflammation.
  • Weight Management: Low-calorie, high-satiety snack option.

Culinary Uses & Tips

  • Snacking: Pair with nut butter, cream cheese, or yogurt dips.
  • Cooking: Add to soups, stir-fries, and stocks for flavor and texture.
  • Juicing: Combine with cucumber, apple, and lemon for a detoxifying drink.
  • Meal Prep: Pre-cut and store in water to maintain crispness.
  • Kid-Friendly: Use as a vehicle for healthy spreads and toppings.

Tip: To preserve freshness and crunch, store celery sticks in a container of water in the refrigerator. This rehydrates the stalks and keeps them crisp for up to a week. Avoid leaving celery at room temperature for extended periods, as it quickly loses moisture and becomes limp.

Celery Stick Applications Across Industries

Celery sticks are far more than just a crunchy snack—they are a versatile, nutrient-rich vegetable with widespread applications across multiple industries. From food service to health and wellness, celery sticks are valued for their refreshing texture, low calorie content, and natural health benefits. Their crispness and mild flavor make them ideal for culinary use, while their nutritional profile supports dietary and functional applications in modern food systems.

Food Service Industry

Celery sticks are a staple in restaurants, cafes, and bars, where they are served as part of appetizers, crudité platters, or paired with dips like blue cheese, ranch, or hummus. Their satisfying crunch and neutral taste complement a wide range of flavors, making them a popular addition to soups (such as chicken noodle), salads, and stir-fries.

  • Used as a base for appetizers like "ants on a log" (celery with peanut butter and raisins)
  • Commonly included in mirepoix—a flavor base for stocks and sauces—alongside onions and carrots
  • Featured in gourmet dishes for texture contrast and visual appeal

Key insight: Chefs appreciate celery for its ability to enhance both flavor and mouthfeel without overpowering a dish.

Snack Food Industry

In the snack food sector, celery sticks are marketed as a healthy, low-calorie alternative to processed snacks. Pre-cut and packaged celery is often sold alongside single-serve dips, capitalizing on the growing consumer demand for convenient, nutritious options.

  • Available in resealable packs for portion control and freshness
  • Frequently bundled with nut butters or yogurt-based dips for on-the-go nutrition
  • Popular among school lunch programs and workplace wellness initiatives

Market trend: The ready-to-eat vegetable segment is growing, with celery as a top choice due to its natural appeal and minimal processing.

Health and Wellness Industry

Nutritionists, dietitians, and fitness professionals frequently recommend celery sticks as part of balanced diets. With only about 10 calories per stalk and high water and fiber content, they support hydration, digestion, and weight management.

  • Rich in antioxidants like apigenin and luteolin, which may reduce inflammation
  • Contains potassium and vitamin K, supporting heart and bone health
  • Low glycemic index makes it suitable for diabetic meal plans

Wellness tip: Often included in detox diets and clean-eating regimens due to its natural diuretic properties.

Grocery Retail Industry

Retailers offer celery sticks in various formats to meet consumer convenience needs. Whole celery heads are available in the fresh produce section, while pre-cut, washed, and packaged sticks are found in the ready-to-eat or snack aisles.

  • Pre-cut options reduce preparation time for busy shoppers
  • Vacuum-sealed packaging extends shelf life and maintains crispness
  • Often grouped with other snack vegetables like carrots and bell peppers

Retail strategy: Bundling celery with dips or as part of "veggie snack boxes" increases perceived value and sales.

Juice and Beverage Industry

Celery has gained significant popularity in the juice and beverage industry, especially in the form of cold-pressed celery juice. Marketed for its hydrating, alkalizing, and anti-inflammatory properties, it's a common offering in health food stores, juice bars, and wellness cafes.

  • Used in green juices and smoothies to balance stronger flavors like kale or wheatgrass
  • Valued for its high electrolyte content, making it ideal for post-workout recovery drinks
  • Featured in functional beverages targeting gut health and detoxification

Consumer trend: A single 16oz celery juice shot can retail for $7–$10 in premium juice bars, reflecting its status as a "superfood" beverage.

Catering and Events Industry

In catering, celery sticks are a go-to ingredient for creating attractive, healthy, and inclusive food options. They are commonly featured on vegetable platters, hors d'oeuvres spreads, and buffet stations at weddings, corporate events, and conferences.

  • Used in elegant canapés with goat cheese, smoked salmon, or herbed cream cheese
  • Helps fulfill dietary requirements for vegan, gluten-free, and low-carb guests
  • Provides color and texture contrast in mixed vegetable arrangements

Catering advantage: Easy to prepare in bulk and stays fresh when stored properly, reducing last-minute prep stress.

Professional Insight: When sourcing celery sticks for commercial use, consider organic options to meet the growing consumer demand for pesticide-free produce. Additionally, partnering with local farms can ensure freshness and support sustainability goals—key selling points in today’s health-conscious market.

Industry Primary Use Key Benefits Consumer Appeal
Food Service Appetizers, salads, soups Flavor enhancement, texture, versatility High – valued for freshness and crunch
Snack Food Ready-to-eat packaged snacks Low calorie, convenient, healthy Very high – especially among health-focused consumers
Health & Wellness Dietary recommendations, detox plans Hydration, fiber, anti-inflammatory properties Extremely high – linked to wellness trends
Grocery Retail Whole or pre-cut produce Accessibility, freshness, ease of use High – driven by convenience culture
Juice & Beverage Celery juice, smoothies, functional drinks Hydration, electrolytes, low sugar Surging – especially in urban and wellness markets
Catering & Events Veggie platters, hors d'oeuvres Visual appeal, dietary inclusivity High – ideal for diverse guest lists

Additional Considerations

  • Sustainability: Celery is often grown with high water usage; sourcing from sustainable farms improves environmental impact.
  • Storage Tips: Keep celery in airtight containers with a damp cloth to maintain crispness for up to two weeks.
  • Food Safety: Always wash thoroughly or choose pre-washed options to reduce risk of contamination from soil or pesticides.
  • Innovation: Dehydrated celery sticks and celery-based snack chips are emerging as shelf-stable alternatives.
  • Allergen Note: While rare, celery is a recognized allergen in some regions (e.g., EU), requiring labeling in commercial food production.

How To Choose the Best Celery Sticks: A Complete Buyer’s Guide

Selecting high-quality celery—whether whole stalks or pre-cut sticks—is essential for both flavor and nutrition. Celery is a versatile vegetable used in salads, soups, snacks, and juices, so choosing fresh, crisp, and flavorful stalks can significantly enhance your meals. This comprehensive guide walks you through the key factors to consider when purchasing celery, helping you make informed decisions that balance freshness, convenience, cost, and health considerations.

Important Note: Celery is one of the most pesticide-contaminated vegetables according to the Environmental Working Group’s "Dirty Dozen" list. If possible, opt for organic varieties or be sure to wash conventional celery thoroughly before consumption.

Key Factors When Choosing Celery Sticks

  • Freshness

    Always prioritize freshness when selecting celery. For whole stalks, look for firm, tightly packed ribs with a vibrant green hue. The stalks should snap crisply when bent—this indicates optimal moisture content and freshness. Avoid any bunches with limp, rubbery, or hollow stalks, as these are signs of age or poor storage. Pay special attention to the base and leaf tips: dry, brown, or cracked ends suggest the celery is past its prime.

    For pre-cut celery sticks, inspect the packaging carefully. Check the expiration or "best by" date and ensure the container is sealed and free of excess liquid. Slimy textures, cloudy moisture, or yellowing edges are clear signs of spoilage. Fresh-cut celery should appear bright, hydrated, and uniformly cut without browning or oxidation on the cut surfaces.

  • Organic vs. Conventional

    The choice between organic and conventional celery depends on your priorities regarding health, budget, and environmental impact. Organic celery is grown without synthetic pesticides, herbicides, or fertilizers, making it a preferred option for health-conscious consumers and families with young children. Because celery has a porous stalk that can absorb chemicals, organic options may reduce exposure to pesticide residues.

    Conventional celery is typically more affordable and widely available. However, due to its high pesticide residue levels, it's crucial to wash it thoroughly under running water. For even better results, soak it in a mixture of water and vinegar (3:1 ratio) for 10–15 minutes, then rinse and dry. Peeling the outer ridges can also help remove surface contaminants.

  • Flavor and Texture

    The taste and texture of celery vary based on stalk size and growing conditions. Smaller, slender stalks tend to be more tender and have a milder, less fibrous flavor—ideal for raw eating, salads, or children’s snacks. Larger, thicker stalks are more robust and slightly bitter but work well in cooking applications like soups, stews, and stir-fries where they soften and infuse flavor.

    To assess flavor potential, give the bunch a gentle sniff. Fresh celery should have a clean, slightly peppery, green aroma. A dull or musty smell may indicate aging or poor storage. Also, examine the leaves (if attached): bright green, perky leaves are a strong indicator of freshness and enhanced flavor.

  • Price and Value Comparison

    When comparing whole celery stalks to pre-cut sticks, consider both cost and convenience. Whole stalks are generally more economical—often costing up to 50% less per pound than their pre-cut counterparts. They also offer greater versatility, as you can use different parts (leaves, ribs, base) in various recipes.

    Pre-cut celery sticks, while more expensive, save significant prep time and are perfect for quick snacks, lunchboxes, or entertaining. They’re especially convenient for people with limited time or kitchen tools. However, the added processing and packaging contribute to higher prices and reduced shelf life, so evaluate whether the convenience justifies the cost for your needs.

  • Storage and Shelf Life

    Proper storage plays a major role in maintaining celery freshness. Whole stalks can last up to two weeks in the refrigerator when stored correctly. For best results, wrap the entire bunch in aluminum foil or place it in a reusable produce bag. This allows ethylene gas to escape while retaining moisture, preventing limpness.

    Pre-cut celery sticks come in sealed containers and should remain refrigerated at all times. Once opened, consume within 3–5 days for optimal texture and safety. To extend the life of cut celery at home, store it in a container filled with water—this keeps it crisp and hydrated. Change the water every day to prevent bacterial growth.

Selection Factor Whole Celery Stalks Pre-Cut Celery Sticks Pro Tips
Freshness Indicators Firm ribs, bright green color, crisp snap, intact leaves No slime, no discoloration, sealed packaging, clear liquid Smell the base—fresh celery has a clean, green scent
Organic Consideration Highly recommended due to pesticide absorption Check for USDA Organic label on packaging Wash thoroughly or use vinegar soak for conventional celery
Flavor & Use Milder in small stalks; great raw or cooked Convenient for snacking, dips, quick meals Use outer ribs in stocks; inner ribs for salads
Cost Efficiency More affordable per pound; full stalk utilization Premium price for convenience and prep time saved Buy whole and pre-cut at home to save money
Storage Life Up to 14 days when wrapped in foil 3–7 days after opening; follow package date Store cut pieces in water to maintain crunch

Expert Tip: To revive slightly limp celery, cut off the ends and soak the stalks in ice water for 30–60 minutes. This rehydrates the cells and restores crispness, making old celery taste nearly fresh again!

Additional Selection Tips

  • Choose celery with leaves still attached—they’re edible and packed with flavor and nutrients.
  • Avoid celery with visible cracks or splits in the stalks, as they deteriorate faster.
  • If buying in bulk, inspect each bunch individually—supermarkets sometimes mix fresh and older stock.
  • Consider growing your own celery if you use it frequently—it’s challenging but rewarding and ensures peak freshness.
  • Check for sustainability labels or locally grown options to support eco-friendly farming practices.

Choosing the right celery sticks doesn’t have to be complicated. By focusing on freshness, understanding the trade-offs between organic and conventional, and considering how you plan to use and store it, you can make a smart, health-conscious decision every time. Whether you prefer the economy of whole stalks or the ease of pre-cut convenience, a little knowledge goes a long way in maximizing flavor, nutrition, and value.

Frequently Asked Questions About Celery and Health

Q1: Is Celery Stick Good for Weight Loss?

Yes, celery sticks are an excellent choice for individuals aiming to lose or manage their weight. With only about 6–10 calories per medium stalk, celery is one of the lowest-calorie solid foods available. Its high water content (around 95%) and rich dietary fiber contribute significantly to satiety—helping you feel full longer without consuming excess calories.

  • Low Energy Density: Foods like celery that are high in water and fiber but low in calories help reduce overall calorie intake, supporting sustainable weight loss.
  • Natural Appetite Control: Chewing celery stimulates saliva production and digestion, which can reduce cravings and prevent overeating during meals.
  • Healthy Snack Alternative: Replacing high-calorie snacks with celery sticks (e.g., paired with hummus or nut butter in moderation) supports long-term weight management goals.

Including celery in a balanced diet not only aids weight control but also contributes to hydration and digestive health—key components of overall wellness.

Q2: Is It Good to Eat a Celery Stick Every Day?

Yes, consuming celery daily can be a beneficial habit for most people, thanks to its impressive nutrient profile and positive impact on multiple body systems. Regular intake supports several aspects of health due to its rich content of essential vitamins, minerals, and plant compounds.

  • Vitamin K (30–40% DV per cup): Crucial for blood clotting and bone metabolism, helping maintain strong bones and reduce fracture risk.
  • Potassium: Supports healthy blood pressure levels by counteracting the effects of sodium and promoting proper muscle and nerve function.
  • Vitamin C (about 5–10% DV): Acts as an antioxidant, boosting immune function and supporting skin health through collagen production.
  • Antioxidants (like apigenin and luteolin): These phytonutrients have anti-inflammatory and potential anticancer properties, contributing to long-term disease prevention.
  • Digestive Support: The insoluble fiber in celery adds bulk to stool, promoting regular bowel movements and supporting a healthy gut microbiome.

When included as part of a varied diet, daily celery consumption can enhance heart health, support immunity, and promote digestive wellness without adverse effects for most individuals.

Q3: Who Should Avoid Eating Celery?

While celery is safe and healthy for most people, certain individuals should exercise caution or avoid it altogether due to specific health concerns:

  • Celery Allergy or Oral Allergy Syndrome (OAS): Some people, especially those allergic to birch pollen, may experience OAS when eating raw celery. Symptoms include itching, tingling, or swelling of the lips, mouth, or throat shortly after consumption. In rare cases, this can progress to more severe allergic reactions.
  • Low-Sodium Diets: Although celery is naturally low in sodium compared to processed foods, it contains more sodium than most vegetables (about 30–50 mg per stalk). For individuals on strict sodium restrictions (e.g., those with heart failure or kidney disease), even natural sources may need monitoring.
  • Digestive Sensitivities: Consuming large amounts of raw celery may cause bloating, gas, or gastrointestinal discomfort in sensitive individuals due to its high fiber and mannitol content (a natural sugar alcohol).
  • Blood-Thinning Medications: Because celery is rich in Vitamin K—a key factor in blood clotting—those on anticoagulants like warfarin should maintain consistent intake rather than suddenly increasing or decreasing consumption to avoid interfering with medication efficacy.

If you have any of these conditions, consult your healthcare provider before making celery a regular part of your diet.

Q4: How Many Celery Sticks Can One Eat a Day?

There is no official recommended daily limit for celery consumption, but moderation is key to avoiding potential side effects. For most adults, consuming 1 to 2 cups of chopped celery (approximately 2 to 4 medium stalks) per day is considered safe and nutritionally beneficial.

This amount provides valuable nutrients without overwhelming the digestive system or significantly impacting sodium or Vitamin K levels. However, some wellness trends promote drinking large quantities of celery juice daily—sometimes equivalent to 16+ stalks—which may pose risks:

  • Digestive Upset: Excessive fiber intake can lead to bloating, cramping, or diarrhea in some individuals.
  • Nutrient Imbalance: Relying heavily on celery juice may displace other essential nutrients from the diet if used as a meal replacement without proper planning.
  • Potential Toxin Exposure: Celery ranks relatively high on the Environmental Working Group’s “Dirty Dozen” list due to pesticide residues. Eating large volumes increases exposure risk unless organic or thoroughly washed.

For personalized guidance—especially if using celery for therapeutic purposes or managing a medical condition—consult a registered dietitian or healthcare professional.

Q5: Is It Better to Eat Celery Raw or Juiced?

Both raw celery and celery juice offer health benefits, but they differ significantly in nutritional composition and effects on the body. The best choice depends on your health goals and digestive tolerance.

Aspect Raw Celery Celery Juice
Fiber Content High (1.6g per cup) – supports digestion, gut health, and satiety. Nearly none – fiber is removed during juicing, reducing digestive benefits.
Calorie Level Very low (~16 calories per cup). Slightly higher concentration (~40–50 calories per 16 oz glass).
Nutrient Absorption Slower release due to fiber; steady nutrient uptake. Faster absorption; nutrients enter bloodstream quickly.
Hydration Excellent – high water content promotes fluid balance. Superior – concentrated liquid form enhances hydration.
Digestive Impact Supports regularity and microbiome health. May soothe the gut lining for some; however, lacks prebiotic fiber.
Best For Weight management, fiber intake, snacking, dental health. Quick hydration, detox routines, sensitive digestion (if tolerated).

Bottom Line: Raw celery is generally the healthier option for most people due to its full-spectrum nutrition and fiber content. Celery juice may benefit those seeking rapid hydration or following specific therapeutic protocols, but it should not replace whole vegetables in the diet. For optimal results, consider incorporating both forms in moderation as part of a balanced eating pattern.