Sprouts and Needles of Norway Spruce (Picea abies (L.) Karst.) as Nordic Specialty—Consumer Acceptance, Stability of Nutrients, and Bioactivities during Storage

Abstract

Developing shoots, i.e., sprouts, and older needles of Norway spruce (Picea abies (L.) Karst.) have traditionally been used for medicinal purposes due to the high content of vitamins and antioxidants. Currently, sprouts are available as, for example, superfood and supplements. However, end-product quality and nutritive value may decline in the value-chain from raw material sourcing to processing and storage. We studied (1) impacts of different drying and extraction methods on nutritional composition and antioxidative properties of sprouts and needles, (2) differences between sprouts and needles in nutritional composition and microbiological quality, and (3) production scale quality of the sprouts. Additionally, (4) sprout powder was applied in products (ice-cream and sorbet) and consumer acceptance was evaluated. According to our results, older needles have higher content of dry matter, energy, and calcium, but lower microbial quality than sprouts. Sprouts showed a higher concentration of vitamin C, magnesium, potassium, and phosphorus than older needles. Freeze-drying was the best drying method preserving the quality of both sprouts and needles, e.g., vitamin C content. The antioxidative activity of the sprout extracts were lower than that of needles. Ethanol-water extraction resulted in a higher content of active compounds in the extract than water extraction. Sensory evaluation of food products revealed that on average, 76% of consumers considered sprout-containing products very good or good, and a creamy product was preferred over a water-based sorbet.

Compositional analysis of essential oil and solvent extracts of Norway spruce sprouts by ultrahigh‐resolution mass spectrometry

“…Nevertheless, spruce sprouts offer a considerable business opportunity to the forest owners. An extensive review on the properties and the use of spruce sprouts has been recently published by Jyske et al 24 …”

“…Despite the rich chemistry of spruce sprouts, only a very few studies on their chemical composition have been reported to date 3,24–27 . A deeper understanding on the chemical makeup of spruce sprouts is required to evaluate their potential in different pharmaceutical, nutraceutical or technochemical applications.…”

“…21 Developing needles of spruce, also known as spruce sprouts or buds, are an interesting, yet limitedly available natural resource. 22 Spruce sprouts are highly enriched with vitamin C and other antioxidants, 23,24 and thus they are harvested during the late spring/ early summer to be used as a dietary supplement or to make different culinary products. 24 The harvesting season of spruce sprouts is only a couple of weeks around mid-May to early June.…”

“…22 Spruce sprouts are highly enriched with vitamin C and other antioxidants, 23,24 and thus they are harvested during the late spring/ early summer to be used as a dietary supplement or to make different culinary products. 24 The harvesting season of spruce sprouts is only a couple of weeks around mid-May to early June. Nevertheless, spruce sprouts offer a considerable business opportunity to the forest owners.…”

“…Nevertheless, spruce sprouts offer a considerable business opportunity to the forest owners. An extensive review on the properties and the use of spruce sprouts has been recently published by Jyske et al 24 Despite the rich chemistry of spruce sprouts, only a very few studies on their chemical composition have been reported to date. 3,[24][25][26][27] A deeper understanding on the chemical makeup of spruce sprouts is required to evaluate their potential in different pharmaceutical, nutraceutical or technochemical applications.…”