Single-Gelator Structuring of Hemp Oil Using Agarose: Comparative Assembly, Electronic Nose Profiling, and Functional Performance of Hydroleogels Versus Oleogels in Shortbread Cookies
1Department of Biotechnology and Food Analysis, Wrocław University of Economics and Business, Komandorska 118/120, 53-345 Wrocław, Poland; oliwia.paron@ue.wroc.pl
2Adaptive Food Systems Accelerator–Science Centre, Wrocław University of Economics and Business, Komandorska 118/120, 53-345 Wrocław, Poland
*Correspondence: joanna.harasym@ue.wroc.plAbstract
This study demonstrates an innovative single-gelator approach using agarose (1% and 2% w/w) to structure cold-pressed hemp oil into functional fat replacers for shortbread cookies, achieving a 40% reduction in saturated fatty acids compared to butter. Comprehensive characterization revealed that hydroleogels exhibited superior crispiness (45.67 ± 3.86 N for 2% agarose hydroleogel—HOG 2%) but problematic water activity (0.39–0.61), approaching microbial growth thresholds. Conversely, oleogels showed lower crispiness (2.27–3.43 N) but optimal moisture control (aw = 0.12–0.16) and superior color stability during 10-day storage. Electronic nose analysis using 10 metal oxide sensors revealed that oleogel systems preserved characteristic aroma profiles significantly better than hydroleogels, with 2% agarose oleogel (OG 2%) showing 34% less aroma decay than pure hemp oil. The 2% agarose oleogel demonstrated optimal performance with minimal baking loss (5.87 ± 0.20%), excellent structural integrity, and stable volatile compound retention over storage. Morphological analysis showed that hemp oil cookies achieved the highest specific volume (2.22 ± 0.07 cm3/g), while structured systems ranged from 1.12 to 1.31 cm3/g. This work establishes agarose as a versatile single gelator for hemp oil structuring and validates electronic nose technology for the objective quality assessment of fat-replaced bakery products, advancing healthier food design through molecular approaches.
1. Introduction
The growing demand for healthier baked goods has accelerated research into saturated fat reduction strategies, particularly through lipid structuring technologies. Emulsion-filled gels (EFGs)—biphasic systems featuring oil droplets immobilized in gelled aqueous phases—have emerged as effective fat mimetics in shortbread cookies. Studies demonstrate that inulin-based EFGs with extra virgin olive oil (EVOO) can replace up to 50% of butter while enabling “reduced saturated fat” claims (≥30% reduction) under EU regulations (Regulation EC No 1924/2006) [1,2]. For instance, 40–50% EFG substitution reduces saturated fat by 37.5–54.2 g/100 g, significantly improving nutritional profiles without compromising oxidative stability during storage [3].
Oleogels represent another promising approach, structuring liquid oils (e.g., hemp seed oil) into solid-like networks using gelators like waxes or monoglycerides. These systems mimic the rheological properties of traditional fats while enhancing polyunsaturated fatty acid (PUFA) content [4,5]. Recent innovations combine oleogels with hydrogels to form bigels, which offer synergistic advantages: improved mechanical stability, controlled water/oil interactions, and potential for bioactive compound delivery [6]. Biphasic gelation (bigel) technology has emerged as a novel strategy for structuring liquid oils into solid-like fats without relying on high SFA. Bigels combine oleogelation (OG) and hydrogelation (HG) to entrap both oil and water phases within a three-dimensional network [7]. These systems exhibit solid-like mechanical properties comparable to commercial fats but feature improved SFA:UFA profiles due to the liquid oil component [8,9]. Critically, bigels synergize the advantages of their individual phases: the OG imparts mechanical strength while the HG enhances resistance to permanent deformation [10,11,12]. Recent work by Nutter et al. [12] developed plant-based bigels using rice bran wax (RBW)/soybean oil OG and an alginate/κ-carrageenan HG. These bigels demonstrated rheological properties akin to bakery fats, offering a clean-label (emulsifier-free), plant-based alternative high in PUFA.
Despite these advances, the performance of plant-based oleogels, especially those leveraging nutrient-dense oils like cold-pressed hemp oil, remains underexplored in baked goods. Hemp oil is rich in ω-3/6 PUFAs and antioxidants, making it ideal for developing functional cookies with enhanced lipid quality and potential health benefits [13].
A critical challenge in fat replacement is preserving sensory attributes. EFG studies reveal that exceeding 50% butter substitution alters texture and volatile profiles: higher EFG levels increase hardness (due to gluten development from elevated water availability) and darken color (via inulin-mediated Maillard reactions) [1]. Total butter replacement (100%) with EFGs drastically reduces fracture stress and buttery flavor compounds (e.g., methyl ketones), lowering consumer acceptance [3]. Similarly, volatile profiles shift toward lipid oxidation products (e.g., hexanal) when butter is fully replaced [3]. These results confirm the need to balance nutritional improvements with microstructure and flavor preservation, a gap this study addresses using hemp-based gels. Despite advances in bigel design, few studies have evaluated their performance as solid fat replacers in food matrices [9,14], with minimal research on shortbread products [8]. Existing studies often focus on model systems or partial fat replacement, leaving gaps in understanding how bigels behave in high-fat (≥30% w/w), low-moisture applications like shortbread.
Hemp seed oil emerges as an ideal candidate for structured lipid systems due to its balanced ω-6/ω-3 polyunsaturated fatty acid (PUFA) ratio and high antioxidant content. When incorporated into oleogels or bigels, it not only reduces saturated fats but also introduces potential health benefits, including anti-inflammatory and cardiovascular protective effects [13]. However, successful integration into baked goods requires addressing challenges in product quality. Studies reveal that high replacement levels (>50%) of butter with bigels in shortbread cookies increase hardness (up to 43.33 N) and baking loss (up to 19.34%) while reducing spreadability and lightness (ΔE > 3) due to moisture retention and restricted fat melting [15]. These changes correlate with heightened gluten network formation and limited dough flow during baking, a trade-off that necessitates careful formulation balancing.
This study aims to develop and characterize shortbread cookies in which traditional fats are replaced with hemp-seed-oil-based oleogels and hydroleogels (hydroleogels are hybrid emulgels consisting only of water, oil, and polymer oleogelators). The research focuses on the physicochemical properties, texture, color, water activity, and volatile compound profiles assessment of the cookies immediately after baking and after ten days of storage, specifically evaluating agarose-structured hemp oil systems (both HOG and OG) as full (100%) butter replacers in shortbread.
The replacement of traditional dairy fats in baked goods represents a significant challenge in food technology, particularly regarding the preservation of characteristic volatile compounds that define product quality and consumer acceptance. This study employed PEN3 electronic nose technology to comprehensively analyze volatile emission patterns from shortbread cookies formulated with butter, cold-pressed hemp oil, and novel gel-based fat replacement systems. The experiment assessed six distinct formulations that differ in fat type: traditional butter as the control, pure hemp oil, hydroleogels containing 1% and 2% agarose (HOG 1%, HOG 2%), and corresponding oleogels (OG 1%, OG 2%) prepared through hydroleogel freeze-drying and shearing.
2. Results and Discussion
2.5. Volatiles Release from Different Fat Matrices
The exploitation of an electronic nose provides an objective assessment of the volatile compounds responsible for the aroma profile of cookies formulated with different fat types. Figure 2 presents the sensor responses for cookies at two time points: immediately after baking (day 0) and after 10 days of storage.
Butter-based cookies exhibited stable sensor responses over the storage period, indicating a consistent aroma profile. Notably, W7 (sulfur-organic compounds) showed high responses (3.42 ± 0.08 on day 0 and 3.41 ± 0.01 on day 10), suggesting the presence of sulfur-containing volatiles contributing to the characteristic buttery aroma. Hemp-oil-based cookies demonstrated significant changes in sensor responses over time. W2 (broad-range) showed a high initial response (4.79 ± 1.27 on day 0), which decreased substantially after 10 days (2.16 ± 0.19), indicating a loss of certain volatile compounds during storage. Additionally, W7 responses decreased from 13.57 ± 2.58 to 6.93 ± 1.14, suggesting a reduction in sulfur-containing volatiles.
Hydroleogel-based cookies (HOG 1% and HOG 2%) displayed relatively stable sensor responses over the storage period. For instance, HOG 1% showed W7 responses of 2.55 ± 0.10 on day 0 and 3.56 ± 0.11 on day 10, indicating a slight increase in sulfur-organic compounds. Sensor 6 (broad-methane) responses remained consistent, suggesting stability in aliphatic hydrocarbon content [24]. Oleogel-based cookies (OG 1% and OG 2%) exhibited moderate changes in sensor responses. OG 2% showed a decrease in W2 response from 3.47 ± 1.11 to 2.58 ± 0.48 over 10 days, indicating a reduction in certain volatile compounds. W7 responses also decreased from 10.10 ± 2.15 to 6.61 ± 1.78, suggesting a decline in sulfur-containing volatiles.
The analysis of variance (Table 6) revealed that the type of fat used in cookie formulations influenced the sensor responses across all sensors (p < 0.05). Storage time had a significant effect on sensors 2, 7, and 9, indicating changes in specific volatile compounds over time. The interaction between fat type and storage time was also notable for sensors 1–3 and 7–10, suggesting that the impact of storage on aroma profile varies depending on the fat type used.
The PEN3 sensor array data reveals distinct differences in volatile organic compound (VOC) formation among fat replacement systems, reflecting crucial alterations in thermally induced biochemical pathways and volatile releases dependent on structure [25,26]. Butter-based cookies exhibited characteristically high responses in W1C (aromatics) and W7 (sulfur compounds), reflecting dairy-specific Maillard reactions between milk proteins and reducing sugars that generate benzaldehyde derivatives and sulfur-containing volatiles like methanethiol [27,28,29,30].
This molecular pathway involves lysine/arginine residues forming Amadori rearrangement products that undergo cyclization and dehydration [28,29,30]. In contrast, W3C (ammonia/amines) responses confirmed the absence of protein-derived volatile precursors in plant-based systems, as the thermal deamination of asparagine/glutamine residues cannot occur without dairy proteins [31,32].
Hemp oil systems showed fundamentally different profiles, with pure oil (O) displaying intense initial responses in W5S (nitrogen oxides/reactive gases) and W7, indicating the rapid lipid oxidation of PUFAs generating hexanal and reactive aldehydes [31]. The 49% decrease in W7 response (13.57→6.93) over storage signals the progressive degradation of desirable nutty notes into stale aromas.
Structured systems modified this degradation: OG 2% demonstrated superior oxidative stability with smaller W7 reductions (10.10→6.61), preserving terpenes captured by W2W (sulfides), while HOGs maintained stable but distinct profiles with elevated W5C (aliphatic hydrocarbons) responses, indicating the hydrogel entrapment of lipid-derived volatiles.
Agarose’s molecular entrapment efficacy was evidenced by systematically reduced volatile release with increasing concentration. Hydrogen bonding between agarose chains creates a 3D network restricting diffusion [33], with denser 2% matrices showing enhanced retention. Critically, W1C responses confirmed that all plant-based systems lacked dairy-type Maillard aromatics, regardless of matrix modification—an irreplaceable sensory limitation. The convergence of hydroleogel and oleogel profiles at equivalent concentrations (e.g., HOG 1% vs. OG 1% W5C: 1.34 vs. 0.95) indicates that preserved polymer architecture post-lyophilization governs volatile mobility more than hydration state.
Butter’s stable fingerprint correlates with consistent “rich, creamy” notes [34], while pure hemp oil’s volatile decay manifests as a progression from initial “herbal” to “rancid”. HOGs’ stability suggests muted aroma development due to aqueous-phase entrapment, whereas OG 2% best preserves the intended “nutty” hemp character during shelf life. This is corroborated by OG 2%’s minimal changes in W3S (alkanes), indicating the effective encapsulation of oxidation-sensitive PUFAs.
The e-nose conclusively identifies OG 2% as maintaining the most stable hemp-like volatile fingerprint during storage, with 34% less aroma decay than pure hemp oil. HOGs preserve a different (water-moderated) profile, while butter remains sensorially distinct due to irreplaceable dairy protein volatiles. This stability differential reflects inherent antioxidant properties in dairy systems versus the oxidative susceptibility of plant-based PUFAs [35], with agarose structuring significantly mitigating degradation in OG 2%.
The optimal volatile release from 1% agarose systems reflects balanced polymer network porosity, while denser 2% matrices may over-restrict diffusion. These findings establish electronic nose technology as a powerful tool for quantifying butter replacement effectiveness, achieving >90% classification accuracy as demonstrated by Rivai and Aulia [36], with hydroleogels showing particular promise for aroma preservation [21,37,38].
3. Materials and Methods
3.1. Raw Materials
The raw materials used for the preparation of shortbread cookies included butter with 82% fat content (Mleczna Dolina, Sulechów, Poland) and cold-pressed hemp seed oil (BioNaturalis, Lublin, Poland). The choice of cold-pressed hemp seed oil was guided by its favorable functional and nutritional properties. Hemp seed oil is rich in polyunsaturated fatty acids, particularly essential omega-6 and omega-3 fatty acids in a beneficial 3:1–5:1 ratio [39]. This fatty acid profile supports improved texture and moisture retention in baked goods when compared to traditional fats. Moreover, studies have shown that emulsions or oleogels based on hemp seed oil can effectively substitute for conventional fats in cookies while maintaining desirable rheological and sensory qualities [13]. Nutritionally, hemp oil contains phytosterols and tocopherols, which are associated with cholesterol-lowering and antioxidant effects, thus enhancing the health profile of the final product. Together, these characteristics made cold-pressed hemp seed oil an ideal choice for formulating shortbread cookies with improved nutritional value, appealing texture, and functional stability [40]. As dry ingredients, type 480 wheat flour (Szymanowska, Polskie Młyny, Poland) and icing sugar were applied. Icing sugar was prepared by mechanically grinding refined white sugar (Cukier Polski S.A.,Toruń, Poland).
Agarose (PRONA basic LE, PRONA GmbH, Legden, Germany) was used as the sole structuring agent for both hydroleogels and oleogels. Agarose is a natural, linear polysaccharide extracted from red seaweeds such as Gelidium and Gracilaria. It is composed of alternating units of β-D-galactose and 3,6-anhydro-α-L-galactose (agarobiose), which together form the repeating disaccharide units of its backbone. Agarose is the primary gelling component of agar and is responsible for its unique gel-forming properties at low concentrations. The gelation of agarose occurs through the formation of double helices stabilized by hydrogen bonds, which then aggregate into a three-dimensional network upon cooling. This thermoreversible gelation mechanism produces transparent and firm gels with tunable rheological properties depending on the concentration, temperature, and molecular weight [41]. Due to its non-toxic and biocompatible nature, agarose is widely used in biomedical and food applications. In food systems, it serves as a clean-label structure-forming agent, enabling the development of hydrogel or oleogel systems with desirable texture and stability. Moreover, compared to agar, agarose contains fewer charged groups (such as sulphates), which contributes to stronger gelation and lower syneresis under comparable conditions [42].
All materials were purchased from local Polish retail distributors. Butter was used as the reference fat in the control cookie formulation, while the hemp oil and its structured forms were tested as alternative fat sources.
3.2. Preparation of Hydroleogels and Oleogels
Agarose hydrogels were prepared at two concentrations: 1% and 2% (w/w). Appropriate amounts of agarose (PRONA basic LE) were weighed into laboratory flasks and dissolved in distilled water. These concentrations were selected based on both practical considerations and manufacturer recommendations, which suggest using agarose up to 2% w/w. The choice was also inspired by previous work by K. Banaś [17], who used 1% and 3% concentrations of agar. However, agarose forms significantly stiffer gels at the same concentrations, and preliminary tests showed that 3% agarose resulted in a very rigid structure unsuitable for food applications. Therefore, 1% and 2% concentrations were selected as optimal to ensure oil entrapment while maintaining a stable yet soft and food-compatible texture. The mixtures were sterilized using an autoclave (Microjet autoclave, BiotoolSwiss GmbH, Switzerland) to ensure full solubilization and microbial safety. After autoclaving, the 1% agarose solution was cooled to 45 °C and the 2% solution to 55 °C, respectively. In parallel, cold-pressed hemp seed oil was heated to the same target temperatures: 45 °C for the 1% system and 55 °C for the 2% system. Once both phases reached the desired temperature, the aqueous agarose solution was added to the oil phase in a 1:1 (w/w) ratio. The mixture was homogenized for 1 min at 10,000 rpm using a high-speed mechanical homogenizer (Yellow line DI 18 Basic, IKA®-Werke GmbH & Co. KG, Königswinter, Germany) to obtain a uniform emulsion. The resulting hydroleogels were left to cool and solidify at room temperature.
To obtain oleogels, the hydroleogels were subjected to a freeze-drying process. Samples were frozen at −70 °C and subsequently lyophilized for 23 h (lyophilizer Alpha 1-4 LSCplus, Martin Christ Gefriertrocknungsanlagen GmbH, Osterode am Harz, Germany). The freeze-dried materials were mechanically ground and redispersed by homogenization for 1 min at 10,000 rpm using the same homogenizer, yielding structured oleogels.
4. Conclusions
This study confirms that structuring cold-pressed hemp oil using agarose as the sole gelator is not only feasible but also effective for producing high-quality shortbread cookies. Hydroleogels and oleogels based on agarose proved to be capable fat replacers, delivering improved nutritional profiles while maintaining key technological and sensory properties. Among the tested variants, OG 2% showed the best overall performance in terms of texture, morphology, aroma stability, and water activity. PEN3 electronic nose analysis provides comprehensive insights into the volatile behavior of alternative fat systems in shortbread cookie applications. The fundamental differences between dairy and plant-based systems, particularly regarding protein-derived volatiles, represent inherent challenges that cannot be fully addressed through matrix engineering alone. However, gel-based systems demonstrate significant potential for enhancing volatile complexity compared to pure hemp oil while providing processing advantages and improved functionality. The convergence of hydroleogel and oleogel volatile profiles at equivalent agarose concentrations simplifies formulation decisions, while the systematic concentration effects provide predictable optimization pathways. These findings demonstrate that successful fat replacement requires understanding molecular-level interactions between lipid matrices, protein components, and polysaccharide networks. The inability to replicate dairy-specific Maillard reaction products through matrix modification highlights the molecular specificity of protein-derived volatile formation pathways. Future developments in fat replacement technology must address these molecular limitations through targeted protein incorporation or enzymatic flavor enhancement strategies. The use of agarose as a natural, safe, and functional gelator presents an attractive strategy for formulating plant-based bakery products with reduced saturated fat content. Future research should explore the further optimization of agarose concentration and evaluate its potential in other food applications.
Acknowledgments
The authors thank Patryk Słota for help.
Institutional Review Board Statement
Not applicable.
Data Availability Statement
All data are included in the article.
Conflicts of Interest
The authors declare no conflicts of interest.
| Fat type | T [min] | Hardness [N] | Cohesiveness | Springiness | Gumminess [N] | Resilience |
|---|---|---|---|---|---|---|
| B | 5 | 37.30 ± 1.92 e,B | 0.09 ± 0.01 a,A | 0.37 ± 0.15 c,B | 3.47 ± 0.55 d,B | 1.86 ± 0.16 bc,B |
| 15 | 16.33 ± 0.81 e,A | 0.14 ± 0.00 a,B | 0.09 ± 0.01 c,A | 2.21 ± 0.08 d,A | 0.17 ± 0.01 bc,A | |
| O | 5 | 3.87 ± 0.95 a,B | 0.06 ± 0.01 a,A | 0.26 ± 0.04 b,B | 0.21 ± 0.03 a,B | 0.65 ± 0.29 ab,B |
| 15 | 3.12 ± 0.81 a,A | 0.04 ± 0.01 a,B | 0.16 ± 0.02 b,A | 0.14 ± 0.05 a,A | 0.39 ± 0.04 ab,A | |
| HOG 1% | 5 | 5.65 ± 0.51 ab,B | 0.27 ± 0.00 b,A | 0.35 ± 0.03 d,B | 1.54 ± 0.12 c,B | 0.29 ± 0.02 a,B |
| 15 | 3.25 ± 0.78 ab,A | 0.34 ± 0.12 b,B | 0.37 ± 0.02 d,A | 1.05 ± 0.08 c,A | 0.29 ± 0.06 a,A | |
| HOG 2% | 5 | 8.35 ± 1.61 c,B | 0.23 ± 0.02 b,A | 0.32 ± 0.04 d,B | 1.86 ± 0.27 c,B | 0.27 ± 0.04 a,B |
| 15 | 4.22 ± 0.03 c,A | 0.27 ± 0.01 b,B | 0.34 ± 0.00 d,A | 1.13 ± 0.07 c,A | 0.27 ± 0.03 a,A | |
| OG 1% | 5 | 6.22 ± 0.36 bc,B | 0.09 ± 0.01 a,A | 0.09 ± 0.01 a,B | 0.55 ± 0.05 b,B | 0.30 ± 0.03 a,B |
| 15 | 5.92 ± 0.12 bc,A | 0.10 ± 0.00 a,B | 0.10 ± 0.01 a,A | 0.57 ± 0.01 b,A | 0.28 ± 0.10 a,A | |
| OG 2% | 5 | 9.08 ± 0.48 d,B | 0.07 ± 0.00 a,A | 0.17 ± 0.01 ab,B | 0.65 ± 0.05 b,B | 1.07 ± 0.82 d,B |
| 15 | 7.72 ± 0.44 d,A | 0.08 ± 0.00 a,B | 0.16 ± 0.01 ab,A | 0.58 ± 0.05 b,A | 1.67 ± 0.39 d,A | |
| Fat type | *** | *** | *** | *** | *** | |
| Time | *** | * | *** | *** | * | |
| Fat type × Time | *** | ns | *** | *** | *** | |
| Different Types of Fats | ||||||
| Fat type | B | O | HOG 1% | HOG 2% | OG 1% | OG 2% |
| L* | 92.58 ± 0.17 c | 44.79 ± 0.97 a | 54.75 ± 3.53 b | 55.68 ± 1.58 b | 56.81 ± 1.70 b | 53.89 ± 0.20 b |
| a* | −4.04 ± 0.02 b | −5.29 ± 0.39 ab | −1.30 ± 0.14 c | −1.38 ± 0.10 c | −5.99 ± 1.22 a | −4.74 ± 0.79 ab |
| b* | 21.75 ± 0.42 a | 21.26 ± 0.67 a | 26.85 ± 1.74 ab | 27.43 ± 1.24 ab | 45.70 ± 6.61 c | 37.43 ± 9.97 bc |
| C | 24.57 ± 0.42 a | 38.17 ± 0.92 cd | 41.31 ± 4.87 d | 39.42 ± 0.86 d | 34.03 ± 1.23 bc | 32.40 ± 0.86 b |
| h | 99.13 ± 0.17 b | 99.83 ± 0.74 b | 100.25 ± 0.62 b | 100.15 ± 1.27 b | 96.50 ± 0.54 a | 96.65 ± 1.15 a |
| Raw dough prepared with different fat types | ||||||
| Fat type | B | O | HOG 1% | HOG 2% | OG 1% | OG 2% |
| L* | 80.45 ± 2.04 d | 47.24 ± 0.77 a | 57.23 ± 1.41 c | 53.69 ± 0.23 b | 53.57 ± 0.84 b | 55.76 ± 0.89 bc |
| a* | −0.67 ± 0.15 d | 2.53 ± 0.45 e | −3.53 ± 0.11 b | −3.05 ± 0.07 c | −4.20 ± 0.08 a | −3.88 ± 0.09 ab |
| b* | 22.81 ± 0.28 b | 17.13 ± 0.35 a | 24.87 ± 0.95 c | 23.10 ± 0.37 b | 23.29 ± 0.46 b | 24.49 ± 0.39 c |
| C | 27.47 ± 0.16 a | 26.35 ± 0.39 a | 38.24 ± 1.40 c | 36.10 ± 0.86 b | 36.75 ± 0.63 bc | 38.22 ± 0.48 c |
| h | 91.40 ± 0.29 b | 83.38 ± 1.33 a | 96.08 ± 0.22 c | 95.70 ± 0.22 c | 97.75 ± 0.13 d | 96.75 ± 0.10 cd |
| Fat Type | Time | L* | a* | b* | C | h |
|---|---|---|---|---|---|---|
| B | 0 | 58.62 ± 0.76 c,A | 6.19 ± 0.26 d | 21.21 ± 0.16 b | 30.92 ± 0.19 d,B | 77.18 ± 0.57 a,A |
| 10 | 61.08 ± 1.03 c,B | 5.27 ± 0.34 d | 21.17 ± 0.24 b | 29.87 ± 0.41 d,A | 78.83 ± 0.74 a,B | |
| O | 0 | 47.24 ± 0.77 b,A | 2.53 ± 0.45 b | 17.13 ± 0.35 a | 26.35 ± 0.39 a,B | 83.38 ± 1.33 c,A |
| 10 | 48.96 ± 0.89 b,B | 2.62 ± 0.26 b | 18.40 ± 0.28 a | 28.27 ± 0.89 a,A | 83.70 ± 0.45 c,B | |
| HOG 1% | 0 | 60.57 ± 1.85 d,A | −1.09 ± 0.59 a | 23.52 ± 0.30 b | 33.86 ± 0.95 cd,B | 92.00 ± 1.15 e,A |
| 10 | 62.25 ± 1.19 d,B | −0.44 ± 0.31 a | 19.50 ± 0.08 b | 26.10 ± 0.31 cd,A | 91.03 ± 0.74 e,B | |
| HOG 2% | 0 | 60.81 ± 0.82 d,A | −0.96 ± 0.37 a | 23.22 ± 0.23 b | 33.16 ± 0.61 d,B | 91.80 ± 0.74 e,A |
| 10 | 63.57 ± 1.43 d,B | −0.49 ± 0.42 a | 20.20 ± 1.48 b | 27.00 ± 2.13 d,A | 91.15 ± 1.10 e,B | |
| OG 1% | 0 | 46.55 ± 1.22 b,A | 2.52 ± 0.65 b | 18.05 ± 0.67 a | 28.48 ± 0.84 bc,B | 83.85 ± 1.80 d,A |
| 10 | 48.62 ± 0.43 b,B | 1.63 ± 0.21 b | 18.86 ± 0.22 a | 29.22 ± 0.28 bc,A | 86.20 ± 0.56 d,B | |
| OG 2% | 0 | 45.15 ± 0.49 a,A | 3.61 ± 0.26 c | 15.86 ± 3.62 a | 28.41 ± 0.15 ab,B | 81.15 ± 0.65 b,A |
| 10 | 46.17 ± 0.16 a,B | 3.32 ± 0.03 c | 17.88 ± 0.10 a | 28.36 ± 0.15 ab,A | 81.90 ± 0.08 b,B | |
| fat type | *** | *** | *** | *** | *** | |
| time | *** | ns | ns | *** | * | |
| fat type × time | ns | *** | *** | *** | *** | |
| Fat Type | Time | Crispiness [N] | Change in Crispiness in Time [N] | Water Activity |
|---|---|---|---|---|
| B | 0 | 16.52 ± 1.14 c,B | 4.55 ± 1.54 ab | 0.16 ± 0.01 b,A |
| 10 | 11.97 ± 0.40 c,A | 0.18 ± 0.01 b,B | ||
| O | 0 | 7.67 ± 1.23 b,B | 0.63 ± 1.86 a | 0.06 ± 0.00 a,A |
| 10 | 7.03 ± 1.55 b,A | 0.08 ± 0.01 a,AB | ||
| HOG 1% | 0 | 35.07 ± 3.84 d,B | −1.03 ± 4.69 a | 0.61 ± 0.02 d,A |
| 10 | 36.10 ± 2.21 d,A | 0.53 ± 0.01 d,B | ||
| HOG 2% | 0 | 45.67 ± 3.86 e,B | 11.27 ± 7.70 b | 0.39 ± 0.07 c,A |
| 10 | 34.40 ± 4.33 e,A | 0.47 ± 0.01 c,B | ||
| OG 1% | 0 | 3.43 ± 0.77 ab,B | −0.50 ± 1.15 a | 0.12 ± 0.01 b,A |
| 10 | 3.93 ± 0.78 ab,A | 0.15 ± 0.01 b,B | ||
| OG 2% | 0 | 2.27 ± 0.28 a,B | 0.45 ± 0.61 a | 0.13 ± 0.01 b,A |
| 10 | 1.82 ± 0.76 a,A | 0.16 ± 0.01 b,B | ||
| Fat type | *** | - | *** | |
| Time | *** | - | * | |
| Fat type × Time | *** | - | *** | |
| Appearance | ||||||
|---|---|---|---|---|---|---|
| Fat Type | B | O | HOG 1% | HOG 2% | OG 1% | OG 2% |
| Specific volume [cm3/g] | 1.51 ± 0.09 b | 2.22 ± 0.07 c | 1.13 ± 0.10 a | 1.31 ± 0.06 ab | 1.12 ± 0.05 a | 1.23 ± 0.09 a |
|
Spreadability
[%] | 2.83 ± 0.64 c | 2.83 ± 0.64 c | −1.85 ± 0.68 a | −1.59 ± 0.27 a | −1.00 ± 0.57 ab | −0.47 ± 0.29 b |
|
Total baking loss
[%] | 9.00 ± 0.34 c | 8.03 ± 1.07 c | 14.82 ± 0.74 d | 15.71 ± 0.67 d | 4.07 ± 2.04 a | 5.87 ± 0.20 b |
| Day 0 | |||||||
|---|---|---|---|---|---|---|---|
| Fat Type | Butter | Oil | HOG 1% | HOG 2% | OG 1% | OG 2% | |
| Sensors [G0/G] | (1) | 0.99 ± 0.01 c | 0.96 ± 0.00 b | 0.94 ± 0.01 a | 0.95 ± 0.01 a | 0.98 ± 0.00 b | 0.95 ± 0.01 a |
| (2) | 1.76 ± 0.09 a,B | 4.79 ± 1.27 c,B | 1.74 ± 0.04 ab,B | 1.76 ± 0.06 ab,B | 2.13 ± 0.01 ab,B | 3.47 ± 1.11 bc,B | |
| (3) | 1.00 ± 0.01 c | 0.99 ± 0.00 c | 0.96 ± 0.00 a | 0.97 ± 0.00 a | 1.00 ± 0.00 bc | 0.98 ± 0.00 b | |
| (4) | 0.98 ± 0.03 ab | 0.95 ± 0.02 a | 1.07 ± 0.01 b | 1.14 ± 0.11 c | 0.96 ± 0.00 ab | 0.99 ± 0.01 ab | |
| (5) | 1.00 ± 0.00 bc | 1.00 ± 0.00 c | 0.98 ± 0.00 a | 0.98 ± 0.00 a | 1.00 ± 0.00 b | 1.00 ± 0.00 b | |
| (6) | 0.98 ± 0.06 ab | 0.95 ± 0.02 a | 1.34 ± 0.05 c | 1.25 ± 0.05 c | 0.95 ± 0.00 b | 1.04 ± 0.01 b | |
| (7) | 3.42 ± 0.08 a,B | 13.57 ± 2.58 c,B | 2.55 ± 0.10 a,B | 2.74 ± 0.09 a,B | 6.17 ± 0.22 ab,B | 10.10 ± 2.15 bc,B | |
| (8) | 1.02 ± 0.03 a | 1.09 ± 0.00 a | 1.12 ± 0.03 b | 1.11 ± 0.00 b | 1.03 ± 0.00 a | 1.11 ± 0.02 b | |
| (9) | 1.96 ± 0.04 a,B | 5.20 ± 0.63 b,B | 1.71 ± 0.04 a,B | 1.77 ± 0.04 a,B | 2.84 ± 0.10 a,B | 4.13 ± 0.74 b,B | |
| (10) | 0.99 ± 0.03 b | 0.93 ± 0.01 a | 1.17 ± 0.02 c | 1.13 ± 0.02 c | 0.95 ± 0.00 b | 0.98 ± 0.01 b | |
| After 10 days | |||||||
| Fat type | B | O | HOG 1% | HOG 2% | OG 1% | OG 2% | |
| Sensors[G0/G] | (1) | 0.98 ± 0.00 c | 0.99 ± 0.01 b | 0.94 ± 0.00 a | 0.95 ± 0.00 a | 0.96 ± 0.00 b | 0.95 ± 0.00 a |
| (2) | 1.72 ± 0.04 a,A | 2.16 ± 0.19 c,A | 2.27 ± 0.07 ab,A | 1.97 ± 0.08 ab,A | 2.12 ± 0.21 ab,A | 2.58 ± 0.48 bc,A | |
| (3) | 1.00 ± 0.00 c | 1.00 ± 0.01 c | 0.97 ± 0.00 a | 0.97 ± 0.00 a | 0.98 ± 0.00 bc | 0.98 ± 0.00 b | |
| (4) | 0.98 ± 0.01 ab | 0.94 ± 0.02 a | 1.05 ± 0.00 b | 1.03 ± 0.01 c | 1.00 ± 0.01 ab | 0.99 ± 0.01 ab | |
| (5) | 1.00 ± 0.00 bc | 1.01 ± 0.00 c | 0.98 ± 0.00 a | 0.99 ± 0.00 a | 0.99 ± 0.00 b | 0.99 ± 0.00 b | |
| (6) | 1.01 ± 0.04 ab | 0.90 ± 0.05 a | 1.33 ± 0.03 c | 1.23 ± 0.06 c | 1.10 ± 0.05 b | 1.09 ± 0.02 b | |
| (7) | 3.41 ± 0.01 a,A | 6.93 ± 1.14 c,A | 3.56 ± 0.11 a,A | 3.32 ± 0.04 a,A | 4.99 ± 1.85 ab,A | 6.61 ± 1.78 bc,A | |
| (8) | 1.04 ± 0.02 a | 1.03 ± 0.02 a | 1.15 ± 0.00 b | 1.11 ± 0.01 b | 1.10 ± 0.01 a | 1.14 ± 0.01 b | |
| (9) | 1.86 ± 0.01 a,A | 2.93 ± 0.32 b,A | 2.00 ± 0.03 a,A | 1.91 ± 0.01 a,A | 2.41 ± 0.55 a,A | 2.88 ± 0.52 b,A | |
| (10) | 1.00 ± 0.04 b | 0.91 ± 0.03 a | 1.12 ± 0.01 c | 1.08 ± 0.02 c | 1.02 ± 0.04 b | 1.03 ± 0.00 b | |
| Statistical analysis | |||||||
| Fat type | Time | Fat type × Time | |||||
| Sensors | (1) | *** | ns | *** | |||
| (2) | *** | * | ** | ||||
| (3) | *** | ns | *** | ||||
| (4) | *** | ns | ns | ||||
| (5) | *** | ns | *** | ||||
| (6) | *** | ns | ns | ||||
| (7) | *** | *** | *** | ||||
| (8) | *** | ns | *** | ||||
| (9) | *** | *** | *** | ||||
| (10) | *** | ns | *** | ||||