Yarns developed from alternative fiber sources are becoming more available as their popularity grows. Let’s compare some production techniques, characteristics and uses of these yarns from uncommon plant and animal sources.
Rayon and bast fibers
Rayon is fiber made from the synthetic process of turning a plant’s fiber into cellulose “soup” then extruding the mixture into filaments that can be spun into yarn. Rayon was initially made mostly from eucalyptus but any plant fiber (soy, bamboo, banana) can be made into Rayon. Tencel, Viscose, Modal and Lyocell are alternate names for Rayon, all referring to yarns made from variations of the cellulose-soup and extrusion process.
Rayon, or plant-based yarns, can be an excellent choice for people who are allergic to animal proteins or react to animal-based yarns. They are often described as antibacterial. Information from test labs and from several fiber manufacturers is contradictory, so our team is waiting for more evidence before providing antibacterial information.
Bast fibers are long fibers from the stems of certain plants. They are softened and then spun into yarn. Banana fiber, as well as more-common linen, hemp and jute fibers, is usually handled like a bast fiber instead of going through the rayon process.
Milk Yarn
Milk yarn, made from protein that’s collected from waste milk, is not Rayon because it is from an animal source. The soup-and-extrusion process is similar, but milk yarn characteristics are more like wool than cotton. It is often crimped during processing to emulate wool fiber even more closely.
Originally developed in Italy in 1935, milk yarn has commonly been blended with other fibers and has been called “Milk Wool” and “Milk Cotton”. Manufacturers are continuing to develop production methods for pure milk fiber. The newest process has been certified green under the Oeko-Tex Standard 100, meaning that the manufacturing process is environmentally benign.
Characteristics of milk yarn
- Soft and warm, produced with a crimp making it even more wool-like
- Glossy, drapey, strong, durable, and wrinkle-free
- Takes color well
- Machine washable although more fragile when wet and can be prone to mildew if left damp
- Absorbs and wicks moisture, breathes well.
- Poor memory/elasticity, so knitted work might “grow” or expand in length as the weight of the fiber pulls the work
How to use milk yarn
- Soft, smooth, strong and washable properties make milk yarn ideal for baby clothes and items like blankets, bibs, toys and carrier covers
- The drapey, colorful and soft characteristics are great for scarves and flowing apparel
- The soft and smooth finish is nice for apparel worn close to the skin like socks, sleepwear, or undergarments
More resources about milk yarn
- Bellatrista Milk Yarn
- Handwoven Yarn Lab: Milk Fiber
Banana Yarn
Produced from the stem of the banana plant, fibers are scraped from the bark and then put through a softening process. The fibers are sorted by density resulting in soft and fine or thick and coarse yarns. Banana is considered eco-friendly as the source plant is renewable (grows quickly), needs few resources to be produced, has very little waste and is completely biodegradable.
Characteristics of banana yarn
- Strong and durable, banana fiber is commonly used in paper, currency, rope and cables
- Stiff at first, products soften with use. Banana yarn is not stretchable
- Silky, soft and lightweight with a comfortable hand that is compared to silk and has been called “banana silk”
- Breathable
- Good wicking from the quick absorption and release of water
- Machine washable but wrinkles in dryer
How to use banana yarn
- The coarser fibers combined with good absorbency make great towels, washcloths, and facial scrubs
- Strong and durable household items like rugs and cushions
- Finer fibers make soft, silky and strong scarves, cowls, blankets
- It makes lightweight, cool and wickable summer apparel
More resources about banana yarn
Soy Yarn
Soy protein fiber is a byproduct of the soyfood and tofu industry. In its natural state, soy protein fiber is a light yellow color like raw silk. It takes dye well, especially acid dyes, and is available in a wide range of colors with excellent colorfastness and resistance to sunlight.
Soy is soft and lustrous and stronger than wool and cotton. It’s processed at a high heat so won’t shrink in the wash. It dries quickly and breathes and wicks moisture well, making it comfortable in the summer.
Characteristics of soy yarn
- Strong, soft, silky, lustrous and drapey
- Takes dye well and has good colorfastness
- Breathes well and wicks moisture
- Soy yarn is stretchy and, like silk, can be slippery to handle
How to use soy yarn
- Strong and stretchy, soy yarn makes great socks and baby gear
- Lightweight, drapey summer garments
- Loungewear and fabric worn close to the skin
- Bedding
More resources about soy yarn
Bamboo Yarn
Bamboo cellulose is derived from bamboo grass to make bamboo yarn. This fiber is considered renewable and eco-friendly. It is easy to dye and takes natural dyes well so the toxicity of synthetic dyes can be avoided.
Bamboo loses strength when wet so fabric with a weak structure may need to be handwashed. It is heavier than cotton or wool and delivers less yardage per ounce, making it wise for you to purchase it by yardage, not weight. Although bamboo is inelastic, its weight may cause wet products to stretch when hung to dry. This may be countered by shrinkage when it’s washed. Bamboo can be (and often is) combined with other fibers, especially natural fibers.
Characteristics of bamboo yarn
- Soft, strong, drapey, and lightweight with a lustrous sheen
- Can be weak when wet, may need to be treated like a delicate
- Smooth fiber can be slippery to handle and not very cohesive in finished fabric
- Heavy fabric can stretch in long projects
- Absorbent with great wicking properties
- Shrinks when washed as much as 10% in hot water
How to use bamboo yarn
- Summer tops, tees, lightweight cardigans and summery wraps
- Blended with easy-care fiber like cotton makes it a great choice for kids and baby garments and accessories
- Weakness when wet makes bamboo a poor choice for washcloths or other scrubbing products
- Inelasticity makes it a poor choice for socks or garments that need to stretch
More resources about bamboo yarn
- Bellatrista Bamboo Yarn
- Maurice Brassard Bambou
- Silk City Bamboo
- Spruce Crafts: Knitting with bamboo yarn
Milk, banana, bamboo and soy sold here
Fiber Rhythm offers a limited selection of milk, banana, bamboo and soy yarns from Bellatrista as well as 100% bamboo yarn from Silk City Fibers and from Maurice Brassard. We would love to hear what you think – have you tried any of the alternate fibers? If yes, how did you use it and how did it perform? If you haven’t tried these, are you interested in yarns made from alternative sources? What size, colors, or other characteristics would you look for in the yarn? Our team hopes you will participate in our journey to explore more of these fibers.