Data on terpene content in pre-rolled cone paper infused with terpene-containing flavours based on the formation of a partially soluble precipitate

The high volatility of the terpenes contained in flavour-containing terpene (FCT) products causes the loss of these contents during product storage; thus, measuring the loss of FCT content during storage is important to estimate the final content. This work provides data on the reduction in FCT content of infused pre-rolled paper cones after 1 to 7 days of storage. Determination of FCT content was based on the formation of a reddish-brown precipitate resulting from the reaction of terpene moiety in FCT with sulphuric acid. Then, the absorbance of the precipitate was analysed using the UV-Vis Spectrophotometric method at a visible wavelength of 538 nm. A calibration standard curve was prepared concerning the concentration of the original FCT sample and used to determine the FCT content in infused pre-rolled paper. The FCT content on the first day of storage decreased and increased again after seven days of storage due to condensation. The data on the FCT content reduction as the effect of additive added was also evaluated.


a b s t r a c t
The high volatility of the terpenes contained in flavourcontaining terpene (FCT) products causes the loss of these contents during product storage; thus, measuring the loss of FCT content during storage is important to estimate the final content.This work provides data on the reduction in FCT content of infused pre-rolled paper cones after 1 to 7 days of storage.Determination of FCT content was based on the formation of a reddish-brown precipitate resulting from the reaction of terpene moiety in FCT with sulphuric acid.Then, the absorbance of the precipitate was analysed using the UV-Vis Spectrophotometric method at a visible wavelength of 538 nm.A calibration standard curve was prepared concerning the concentration of the original FCT sample and used to determine the FCT content in infused pre-rolled paper.The FCT content on the first day of storage decreased and increased again after seven days of storage due to condensation.The data on the FCT content reduction as the effect of additive added was also evaluated. ©

Value of the Data
• This paper presents a simple, robust, and highly practicable method for estimating the amount of terpene-containing product based on the formation of a reddish brown precipitate that has a linear response using spectrophotometric measurement at 538 nm.• The data on FCT decrement as the effect of operating conditions would provide insight for the industrial sector into selecting the appropriate method for storing the terpene-infused pre-rolled cone products.• It is anticipated that the data's practicability and applicability will serve as merits for commercialization.

Background
Terpenes have attracted the attention of the industry, especially in cannabis-related industries.The combination of terpenes and cannabinoids produces a psychoactive effect (entourage effect) [ 1 ], which helps reduce anxiety [ 2 ], depression, and inflammation [ 3 ].Infusion in prerolled cones is a convenient and popular method for consuming terpenes, and it offers a timesaving, consistent, portable, and customizable way to enjoy cannabis.Various terpene-infused pre-rolled cone products with various infusion and packaging methods have been marketed.Given their high volatility, terpene degradation in pre-rolled cones is the most challenging problem in product marketing.The terpene content in pre-rolled cones may be reduced when marketed.To date, no method has been reported for estimating the terpene content in infused cones, which makes determining terpene efficacy unclear.A simple and robust method for estimating terpene content in pre-rolled cones has been demonstrated here.This procedure was developed using the Salkowski test to detect terpenoids [3][4][5].The terpenes in the rolled cones are ex-tracted using chloroform and then precipitated using sulphuric acid.The terpene content was then estimated using a spectrophotometric procedure at a wavelength of 538 nm.

Data Description
This paper shows the data on the amount of terpene loss from the infused pre-rolled cones by comparing the amount of FCT infused initially and after 7 days' storage.Estimation of FCT content was carried out based on the formed reddish brown precipitate after employing the measurement procedure by Ghorai et al. [ 6 , 7 ]; the formed precipitate is shown in Fig. 1a .The prepared standard calibration curve corresponding to the percent volume (%v) FCT is provided in Fig. 1b .The obtained data point in the standard curve are well-correlated to the linear model which follows eq. 1, with coefficient of determination ( R 2 ) value of 0.985.y = 0 .0108x + 0 .0245 (1) where y is the absorbance at 538 nm, and x is the FCT content (%v).The obtained linear curve fitting equation is employed to estimate the FCT content in the infused cone paper.

Data on FCT decrement as the effect of tube sealing
The effect of using a plastic (polypropylene) screw cap and rubber cap on a glass tube on the FCT content after 7 days is shown in Fig. 2 .The FCT content was reduced to 7.93 %v from initially 25 %v after 1 day stored, and the content was slightly increased to 9.51 %v.Meanwhile, 22.66 %v of FCT can be maintained after 7 days of being stored in a tube closed with a plastic cap.The use of rubber caps results in low FCT content after 7 days stored as the rubber absorbs the evaporated FCT; using plastic caps can dramatically reduce this issue.

Data on FCT decrement as the effect of added additives
Fig. 3 shows the reduced FCT content in cone paper after incubation for a certain period without any added additives.After 1 day of incubation, the FCT content was reduced to 9.88 %v   from an initial content of 25 %v.The FCT was evaporated from the cone paper during the incubation, resulting in the loss of FCT content.Interestingly, a sharp increase of FCT content in the cone paper was detected after the second day of incubation, and the FCT content kept decreasing until the seventh day of incubation.Our findings highlighted an interesting phenomenon that can be correlated to the condensation of the evaporated FCT.Terpene is soluble in ethanol (EtOH) [ 8 ]; thus, adding EtOH in infusing FCT may help enhance its absorption into the cone paper.The reduction of FCT content with the addition of EtOH is shown in Fig. 4 .The FCT content was reduced after the first day of incubation.A similar phenomenon to the previous result was also observed, where the FCT content increased on the second incubation day.The FCT content was simultaneously decreased up to the seventh day of incubation.
The effect of polypropylene glycol (PPG) addition in the FCT content of the infused cone paper is shown in Fig. 5 .It can be noted that a very high FCT content reduction occurred after the first day of incubation, which can be due to the effect of competition between the PPG and the FCT to be absorbed in the cone paper.Interestingly, the FCT content increased gradually at prolonged incubation time.This phenomenon could be correlated to the role of the absorbed PPG in aiding the fixating of the FCT into the cone paper.PPG is known to have adhesive properties [ 9 ]; thus, it adheres to the surface of cone paper after being heated during infusion.
Fig. 6 shows the effect of EtOH and PPG addition in decreasing FCT content during the incubation period.The combination of EtOH and PPG shows a synergistic effect in maintaining high FCT content after 7 days of incubation, with a final FCT content of 22.65 %v.This synergistic effect can be attributed to the role of EtOH in promoting the diffusion rate of both PPG and FCT into the cone paper and the role of PPG in preventing the saturation of the cone paper by moisture.

Data on FCT decrement from the infused glue
Fig. 7 shows the amount of FCT reduced from the glue mixture after being incubated for 1 day and 7 days.The FCT content was reduced from 10 %v to 2.60 %v after 1 day of incubation and further reduced to 1.01 %v after 7 days of incubation.
The specifications of the pre-rolled cone papers used in this paper are detailed in Table 1 .
All of the chemicals and apparatus used in this study were the same as those intended for large scale production.

FCT standard curve preparation
The FCT standard curve was prepared by adopting the method of Ghorai et al. (2012), with slight modifications.The FCT was pipetted into a reaction tube at various amounts, as shown in Table 2 .Then, ethanol was added to make up the total volume of 200 μL.Subsequently, 1.5 mL of 100 μL of H 2 SO 4 was added into the solution of FCT in chloroform, and the mixture was incubated for 1 h at room temperature with dark conditions.After incubation, the reddish-brown precipitation was formed, and the clear upper layer solution was gently decanted.Subsequently, 2.8 mL of methanol was added to dissolve the precipitation.The absorbance of the sample was measured with a wavelength of 538 nm to determine the FCT content.

Limitations
This study is subjected for practical purposes in estimating the terpene content in the form of FCT.All of the terpene measurements were expressed as the percent volume of FCT.

Fig. 2 .
Fig.2.FCT content decrement as the effect of tube cap type (rubber cap vs. plastic cap) after 1 day and 7 days of storage.

Fig. 3 .
Fig. 3. Detected FCT content after 7 days of incubation at room temperature.The final FCT content after 7 days of incubation is 4.74 %v.

Fig. 4 .
Fig. 4. Detected FCT content after 7 days of incubation at room temperature with EtOH additive.The final FCT content after 7 days of incubation is 5.30 %v.

Fig. 5 .
Fig. 5. Detected FCT content after 7 days of incubation at room temperature with PPG additive.The final FCT content after 7 days of incubation is 10.71 %v.

Fig. 6 .
Fig. 6.Detected FCT content after 7 days of incubation at room temperature, with EtOH and PPG additive.The final FCT content after 7 days of incubation is 22.65 %v.
2024 The Authors.Published by Elsevier Inc.This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

Table 1
Specification of pre-rolled cone paper.