High-nutrition additive-free candy jam based on seaweed dietary fibers and preparation method of high-nutrition additive-free candy jam

Abstract

The invention discloses a high-nutrition additive-free candy jam based on seaweed dietary fibers and a preparation method of the high-nutrition additive-free candy jam. The jam comprises the following components in parts by weight: 55-70 parts of a fruit base material, 0.7-1.3 parts of sugar beet-sourced low-methoxy amidated pectin, 2.2-4.2 parts of a seaweed dietary fiber compound system, 0.06-0.18 part of calcium salt, 0.08-0.25 part of an anthocyanin stable system and the balance of water, and exogenous saccharides and artificial or natural sugar substitutes are not added. Wherein the methoxylation degree of pectin is smaller than or equal to 35%, the amidation degree of pectin is 5-20%, and the seaweed dietary fiber compound system comprises brown seaweed soluble dietary fibers and red seaweed galactan dietary fibers. The preparation method comprises the following steps: pulping at low temperature and adjusting acid, dispersing and hydrating polysaccharide, adding glue in batches, degassing and controlling oxygen in stages, introducing laccase for covalent cross-linking, adding calcium in stages to form ionic cross-linking, adding an anthocyanin stabilizing system, filling at low temperature, and carrying out 580-620MPa ultrahigh pressure treatment. A stable gel structure and good water binding capacity are obtained under the condition of no exogenous sugar, bleeding is reduced, anthocyanin and color stability are improved, and meanwhile non-thermal sterilization and storage period safety are achieved.

Description

Technical Field

[0001] This invention relates to the technical field of food processing and functional foods, and in particular to a high-nutrition, additive-free confectionery sauce based on seaweed dietary fiber and its preparation method. Background Technology

[0002] Jams, as a food product made primarily from fruit, are widely used in baking, spreads, and functional foods due to their concentrated flavor and ease of consumption. Traditional jams typically rely on exogenous sugars such as sucrose, added in high amounts, to work with pectin to form a gel structure. This system not only gives the product a stable texture and good spreadability but also, to some extent, inhibits microbial growth by reducing water activity, thereby extending shelf life.

[0003] However, with the increasing demand from consumers for low-sugar, additive-free, and nutrient-preserving foods, reducing or even eliminating exogenous sugars has become an important development direction for jam products. In the absence of a high-sugar environment, the gel formation mechanism of traditional pectin systems is significantly affected, leading to problems such as loose structure, insufficient rheological properties, and water separation during storage in jam systems. Furthermore, the higher water activity in low-sugar or sugar-free systems also places higher demands on the structural stability and storage safety of the product.

[0004] On the other hand, many jam products use berries rich in anthocyanins, polyphenols, and other natural active substances as raw materials. These components are easily degraded or discolored during processing and storage due to changes in oxygen, metal ions, pH, and processing conditions. In traditional processes, product stability is often improved by heating to sterilize or adding synthetic stabilizers. However, these methods can easily lead to the loss of heat-sensitive nutrients or contradict the trend towards clean labels and fewer additives.

[0005] Therefore, how to simultaneously achieve a stable gel structure, good storage structure maintenance, and stable preservation of natural active ingredients in a jam system without relying on exogenous sugars and high-temperature processing remains a pressing technical problem to be solved in the jam and related fruit product industry. Summary of the Invention

[0006] The purpose of this invention is to solve the problems of insufficient structural stability, water separation during storage, and decreased stability of nutritional active ingredients in existing jam products when exogenous sugars are reduced or eliminated. The invention provides a high-nutrition jam product and its preparation method that still have good textural stability, storage stability, and nutritional retention levels without exogenous sugars.

[0007] To achieve the above objectives, the first aspect of the present invention provides a high-nutrition, additive-free confectionery sauce based on seaweed dietary fiber, comprising the following components by weight: 55-70 parts fruit base; 0.7–1.3 parts of low-methoxylated pectin from beets; 2.2–4.2 portions of seaweed dietary fiber compound system; 0.06–0.18 parts calcium salt; 0.08–0.25 parts anthocyanin stabilization system; The remainder is water. The jam contains no added exogenous sugars or artificial or natural sugar substitutes. The methoxylation degree of the sugar beet-derived low-methoxylated pectin is no higher than 35%, and the amidation degree is 5-20%. The seaweed dietary fiber compound system includes 1.6 to 3 parts of soluble dietary fiber from brown algae and 0.2 to 0.8 parts of galactomannan dietary fiber from red algae.

[0008] By combining fruit base, beet-derived low-methoxyamide pectin, seaweed dietary fiber compound system, and calcium salt in a limited weight ratio, a stable gel-type continuous phase structure is formed without introducing additional exogenous sugars or sugar substitutes. The low-methoxyamide pectin provides carboxyl sites that can undergo ion crosslinking with calcium ions and form a basic three-dimensional network. The seaweed dietary fiber compound system constructs an interpenetrating support phase in this network and improves the water-holding capacity and viscoelasticity of the system, thereby reducing free water migration and inhibiting water separation during storage.

[0009] Meanwhile, the degree of methoxylation of pectin is limited to no more than 35%, and the degree of amidation is limited to 5-20%, so that it can maintain a high calcium-sensitive crosslinking efficiency and controllable crosslinking rate under low sugar or no exogenous sugar environment, avoiding gel dependence on sugar-acid conditions caused by excessive methoxylation of pectin or network looseness caused by insufficient sites.

[0010] Furthermore, by limiting the proportions of soluble dietary fiber from brown algae and galactan dietary fiber from red algae to a specific range, the two types of seaweed polysaccharides exhibit chain segment entanglement and swelling behavior at different scales under ionic strength and shear conditions. This synergistically fills the pores in the pectin crosslinking network and provides fine structural support, thereby achieving spreadable consistency, lower risk of water separation, and more stable texture retention in a system without exogenous sugars.

[0011] As a further improvement of the present invention, the fruit base is selected from one or more of blueberries, blackcurrants, mulberries, and raspberries, and the natural soluble solids content of the fruit base is 8-14 °Brix.

[0012] By specifically defining the fruit base material as described above, all the sweetness in the jam system comes from the natural sugars contained in the fruit itself. At the same time, it ensures that the fruit pulp has sufficient soluble solids as a continuous phase basis for the formation of the polysaccharide network. This solids content range avoids the problem of the system being too thin due to too low solids, making it difficult for pectin and seaweed dietary fiber to form a stable three-dimensional structure, while avoiding the situation where the system has too high osmotic pressure due to too high solids, affecting the uniformity of enzymatic oxidation cross-linking and calcium ion diffusion.

[0013] In addition, the aforementioned berries are generally rich in anthocyanins and polyphenolic compounds. Their natural acidity and antioxidant components can form a synergistic and stable environment with the subsequently constructed pectin-seaweed dietary fiber complex network, making it easier for anthocyanins to be fixed in the gel microstructure without heat treatment. This achieves both no added sugar and good flavor performance and high nutritional retention.

[0014] As a further improvement of the present invention, the calcium salt is selected from calcium lactate or calcium gluconate.

[0015] By limiting the calcium salt to calcium lactate or calcium gluconate, calcium ions are released in an aqueous system in a relatively slow and controllable manner, thereby gradually undergoing ionic cross-linking reactions with the carboxyl sites in low-methoxyamiditized pectin derived from beets. This release characteristic matches the subsequent segmented calcium addition and static rearrangement steps, avoiding the problems of localized excessive cross-linking and structural inhomogeneity caused by the instantaneous dissociation of large amounts of calcium ions. The pectin ionic cross-linking network formed under these conditions has a relatively uniform spatial distribution and continuity, which is beneficial for providing stable skeletal support for the seaweed dietary fiber compound system, allowing polysaccharide segments from different sources to be fully embedded in the network and synergistically constrain water.

[0016] Meanwhile, the organic acid radicals introduced by calcium lactate and calcium gluconate buffer changes in ionic strength in the system, reducing the risk of structural collapse or water redistribution under non-thermal process conditions such as degassing, enzymatic oxidative crosslinking and ultra-high pressure treatment. This improves the stability of the overall gel structure of the jam and its resistance to water separation during storage without affecting the flavor.

[0017] As a further improvement of the present invention, the anthocyanin stabilizing system is composed of the following components in parts by weight: 0.03–0.12 parts ascorbic acid or isoascorbic acid; 0.01–0.05 parts sodium citrate; 0.005–0.03 parts rosemary extract, Furthermore, the ascorbic acid A, sodium citrate B, rosemary extract C, system pH, and dissolved oxygen (DO) satisfy the following relationship: 1 ≤ A / B ≤ 6 and 0.15 ≤ (A × C) / B ≤ 3.0 and (A × C) / (B × DO × pH) = 0.5~6.5; where A, B, and C are in parts by weight, and DO is in mg / L, thereby simultaneously constraining the pathways of free radical scavenging, metal ion complexation, and anthocyanin oxidation.

[0018] By explicitly defining the anthocyanin stabilization system as consisting of ascorbic acid or isoascorbic acid, sodium citrate, and rosemary extract, and further defining the ratio of the three components and their coupling relationship with the system pH and dissolved oxygen content, anthocyanins can obtain a multi-pathway, synergistically controlled stable environment under non-thermal processing conditions.

[0019] Ascorbic acid compounds preferentially react with dissolved oxygen and reactive oxygen species in the system, thereby reducing oxidative stress and delaying the initial oxidation process of anthocyanins. Sodium citrate inhibits metal-catalyzed oxidation reaction pathways through complexation with trace metal ions, while also buffering and stabilizing the pH of the system to prevent anthocyanin structural transformation caused by acidity fluctuations. Phenolic hydroxyl compounds in rosemary extract participate in free radical scavenging under low dissolved oxygen conditions and form a weakly interacting shielding layer on anthocyanin molecules, further reducing their probability of exposure to the oxidative environment.

[0020] By limiting the ratio of A to B and the comprehensive relationship between A, B, C and DO and pH, the three stabilization mechanisms mentioned above are placed in a synergistic range that matches each other in the same system. This avoids the stability imbalance caused by an excessively strong or weak single antioxidant pathway. As a result, the degradation rate of anthocyanins during processing and storage is significantly reduced without relying on heat treatment and synthetic stabilizers, thereby improving the color retention and functional activity retention of jam.

[0021] A second aspect of this invention provides a method for preparing the above-mentioned high-nutrition, additive-free candy sauce based on seaweed dietary fiber, comprising the following steps: S1: Crush the fruit base material and make fruit pulp at a temperature not exceeding 10℃, and adjust the pH of the obtained fruit pulp to 2.9-3.6; S2: The seaweed dietary fiber compound system was dispersed and hydrated at 15-20℃, and then beet-derived low-methoxyamidized pectin was added to the resulting system in two separate portions. S3: Degas the system obtained in step S2 at 10–18°C, and after the degassing is completed, add the enzymatic oxidative crosslinking system at 12–18°C and react. S4: Add calcium salts to the system obtained in step S3 in a segmented manner to form an ionic cross-linked structure; S5: Add the anthocyanin stabilizing system to the system obtained in step S4 and mix thoroughly; S6: The system obtained in step S5 is filled and sealed under low temperature conditions, and then the sealed jam is subjected to ultra-high pressure treatment.

[0022] By limiting the entire jam preparation process to a system temperature that never exceeds 40°C, and then subjecting it to ultra-high pressure treatment after formula development and structural stabilization to achieve commercial sterility, the product avoids the destructive effects of heat input on the system during the two key stages of sterilization and structural stabilization. The low-temperature conditions effectively inhibit the thermal degradation and structural transformation of heat-sensitive nutrients such as anthocyanins, polyphenols, and vitamins, reducing color browning and flavor loss caused by heating.

[0023] Building upon this foundation, ultra-high pressure processing is introduced as a non-thermal sterilization method. By applying instantaneous high pressure, the cell membrane structure and metabolic system of microorganisms are disrupted, thus achieving sterilization without relying on high temperatures. Simultaneously, this high-pressure environment has an overall compaction and locking effect on the already formed pectin ion cross-linking network and enzymatic oxidative covalent cross-linking structure, making the complex polysaccharide network more dense and stable at the microscopic scale. As a result, the jam retains high nutritional activity and natural color while also possessing good microbial safety and storage stability, achieving a synergistic unity between high nutrient retention and clean label characteristics.

[0024] As a further improvement of the present invention, step S3 includes the following stages: S3-1, add food-grade laccase at 12-18℃ and disperse and mix; S3-2 undergoes a first-stage covalent cross-linking reaction at 12–18°C. S3-3 undergoes a second-stage covalent crosslinking reaction at 12–18°C. Furthermore, the amount of laccase added (E), the amount of pectin used (G), the reaction time of the first stage (τ1), the reaction time of the second stage (τ2), the reaction temperature of the first stage (T1), and the reaction temperature of the second stage (T2) satisfy the following relationship: (E×(τ1+τ2)) / (G×((T1+T2) / 2)) = 0.008~0.12, E and G are expressed in parts by weight, τ1 and τ2 in minutes, and T1 and T2 in degrees Celsius.

[0025] By specifically defining the enzymatic oxidative crosslinking system reaction in step S3 as described above, the relationship essentially limits the effective amount of enzymatic action received by a unit of pectin throughout the entire reaction process, thereby avoiding uncontrollable crosslinking deviations caused by simply extending the reaction time, increasing the temperature, or increasing the amount of enzyme.

[0026] Under the control of the relational formula, even if there are differences in activity between different batches of raw materials, or slight fluctuations in reaction time and temperature during actual production, as long as the relational formula is satisfied, the number and distribution density of covalent bonds formed by pectin molecules in the system are still limited to a relatively consistent range.

[0027] Specifically, by initiating covalent cross-linking under milder reaction conditions in the first stage, laccase preferentially forms dispersed initial cross-linking points between pectin segments, thereby establishing a uniform network framework. In the second stage, the reaction continues to supplement the cross-linking density, allowing the network formed in the early stage to gradually connect rather than grow excessively in certain areas. By incorporating the sum of the reaction times of the two stages and the average temperature of the two stages into the relational constraint, the reaction rate and reaction process are essentially weighted and balanced, preventing problems such as excessive cross-linking of local segments, uneven network pore size, or structural rigidity caused by excessively fast reaction in a single stage.

[0028] Furthermore, by directly linking the aforementioned equivalent cross-linking input with the amount of pectin, the resulting covalent cross-linked network is matched with the subsequent calcium salt ion cross-linking step in terms of spatial scale and mechanical properties. This allows calcium ions to diffuse uniformly within the existing covalent network framework and complete secondary shaping during the ion cross-linking process, reducing local shrinkage and water redistribution caused by uneven framework density. Thus, this relationship not only controls the covalent cross-linking reaction itself but also indirectly improves the overall structural stability, water separation resistance, and fixation effect of functional components such as anthocyanins in the complex polysaccharide system under conditions without exogenous sugars by precisely defining the initial network structure.

[0029] As a further improvement of the present invention, step S3 includes the following degassing stage: S3-a, the system obtained in step S2 is subjected to the first stage of degassing treatment, reducing the dissolved oxygen content of the system to 30% to 60% of the initial dissolved oxygen content within 1 to 5 minutes; S3-b, after completing the first stage of degassing, the system undergoes a second stage of degassing to stabilize and control the residual dissolved oxygen in the system. Furthermore, in the second stage of degassing, the dissolved oxygen content (DO), degassing time (t), system temperature (T), and system volume (V) satisfy the following relationship: DO ≤ (0.08×T + 0.015×t) / V, Where DO is expressed in mg / L, t in minutes, T in degrees Celsius, and V in liters.

[0030] By clearly dividing the degassing process into two consecutive stages with different control objectives, and by defining the oxygen reduction rate in the first stage and the residual dissolved oxygen control method in the second stage, a stable and repeatable oxygen environment can be established before the system enters the enzymatic oxidative cross-linking reaction. In the first stage of degassing, the dissolved oxygen content of the system is rapidly reduced to 30% to 60% of the initial dissolved oxygen content within 1 to 5 minutes. This allows the complex system formed by pectin and seaweed dietary fiber to quickly leave the high-oxygen state before the introduction of laccase. This significantly reduces the non-specific consumption of laccase active sites by dissolved oxygen and reactive oxygen species, and avoids the enzyme being used for oxygen removal before participating in the target covalent cross-linking reaction, which would lead to a decrease in the effective enzyme quantity. At the same time, the time scale limitation ensures that the degassing process focuses on rapid removal rather than excessively pursuing extremely low oxygen levels, thereby avoiding structural disturbances in the system due to sudden changes in oxygen conditions in the early stage.

[0031] After completing the first stage of rapid oxygen reduction, the residual dissolved oxygen in the system is stabilized and controlled through the second stage of degassing. A functional relationship is established between the dissolved oxygen content and the degassing time, system temperature, and system volume, so that the residual dissolved oxygen is limited to a threshold range that matches the system scale and thermal state. This provides a relatively constant and repeatable oxygen environment for the laccase catalytic reaction. Under this condition, it is possible to avoid the laccase reaction pathway deviation or promotion of non-target oxidation reactions caused by excessively high dissolved oxygen, and to prevent the reaction start-up delay or reaction rate fluctuation caused by excessively low dissolved oxygen, so that the covalent cross-linking reaction can proceed smoothly according to the expected path.

[0032] By employing the aforementioned staged degassing and differentiated control methods, the degassing operation is transformed from a simple physical deoxygenation step into a pre-regulation mechanism for the enzymatic covalent cross-linking reaction conditions. This not only improves the effectiveness and reproducibility of laccase in the pectin covalent cross-linking reaction but also provides a more uniform structural basis for subsequent ionic cross-linking and ultra-high pressure treatment. Simultaneously, it reduces the oxidative stress of anthocyanins and other polyphenols in the early stages of the reaction, facilitating their fixation and stability during the formation of the complex polysaccharide network. This enhances the structural stability, color retention, and nutritional retention of the exogenous confectionery jam system during processing and storage. As a further improvement of this invention, step S4 includes the following stages: S4-1, add the first stage calcium salt and let stand; S4-2, add the second stage calcium salt and let stand; S4-3, with the addition of the third-stage calcium salt; Furthermore, the total amount of calcium salt added (Ca), the amount of pectin (G), the standing time (Δt), and the system temperature (T) satisfy the following relationship: (Ca×Δt) / (G×T) = 0.06~0.45, Where Ca and G are expressed in parts by weight, Δt in minutes, and T in degrees Celsius.

[0033] By designing the ionic crosslinking process as a three-stage continuous calcium addition and introducing a static rearrangement process in the first two stages, and limiting it with the relationship between the total amount of calcium salt added, the amount of pectin, the static time and the system temperature, the process of calcium ions participating in pectin ionic crosslinking is transformed from a one-time rapid reaction into a controlled diffusion and gradual rearrangement process.

[0034] The first and second stages initiate ionic cross-linking reactions at relatively low instantaneous calcium ion concentrations, allowing calcium ions to gradually diffuse along the formed covalent cross-linking network and bind orderly to the carboxyl sites on the pectin segments. This avoids problems such as localized over-cross-linking, structural inhomogeneity, or granulation caused by the instantaneous concentrated release of calcium ions. A set resting time is set after calcium is added in each stage to allow sufficient time for the ion distribution and segment conformation within the system to spontaneously rearrange, thereby gradually forming ionic cross-linking nodes with a more uniform spatial distribution.

[0035] By incorporating the total amount of calcium salt added, the settling time, and the system temperature into a unified relational constraint, the effective calcium ion interaction intensity received by a unit of pectin during the ionic crosslinking stage is essentially limited. This ensures that the system under different batch conditions and temperature levels can still be controlled within the same equivalent crosslinking window, thereby reducing fluctuations in crosslinking density caused by changes in environmental conditions. Under these conditions, the calcium addition in the third stage is mainly used to replenish crosslinking sites and complete the overall network shaping, without causing damage or re-aggregation of the previous structure. This ensures that the ionic crosslinking network and the aforementioned covalent crosslinking network maintain a good match in terms of spatial scale and mechanical properties.

[0036] Through the synergistic effect of the aforementioned staged calcium addition and relational constraints, the pectin ionic crosslinking process is adapted to the formation sequence and structural state of the covalent crosslinking backbone, reducing the risk of system shrinkage and water redistribution during the crosslinking process. This allows the complex polysaccharide network to maintain high water-holding capacity and structural stability even without exogenous sugars. As a result, not only is the texture retention and water separation resistance of the jam improved during shearing and storage, but a uniform and stable structural basis is also provided for subsequent ultra-high pressure processing, which is conducive to maintaining a stable taste and appearance of the final product during long-term storage.

[0037] As a further improvement of the present invention, the pressure of the ultra-high pressure treatment in step S6 is 580-620 MPa, the treatment temperature is 10-20°C, the pressure holding time is 2.5-5 minutes, and the ultra-high pressure treatment is performed after completing steps S4 and S5.

[0038] By limiting ultra-high pressure (UHPP) treatment to low-temperature conditions after the completion of ionic cross-linking and the introduction of the anthocyanin stabilization system, and by specifying the treatment pressure, temperature, and holding time, UHPP not only serves as a non-thermal sterilization process but also acts as a key step in locking and stabilizing the existing complex polysaccharide structure. Applying high pressure after the completion of both covalent and ionic cross-linking network construction avoids interference with the cross-linking reaction or alteration of the cross-linking pathway, thus ensuring good controllability in the formation of the polysaccharide network structure. The high hydrostatic pressure applied at this stage, acting uniformly within the system, further compacts and stabilizes the already formed pectin and seaweed dietary fiber complex network at the microscale, reducing the free volume and potential defects within the network.

[0039] Meanwhile, by limiting the ultra-high pressure processing temperature to the range of 10–20°C and controlling the holding time, the sterilization process is completed without introducing a heat effect, thus avoiding the degradation or structural transformation of anthocyanins, polyphenols, and other heat-sensitive nutrients due to temperature increases. Under these conditions, high pressure mainly achieves sterilization by disrupting the integrity of microbial cell membranes and metabolic balance, while having little impact on the chemical structure of the already formed polysaccharide cross-linking network and stable system. This ensures the safety of microorganisms while maintaining the original texture and color of the jam.

[0040] By explicitly placing ultra-high pressure processing at the end of the step sequence and establishing a sequential dependency with the preceding structure-building steps, the complex polysaccharide network is fixed as a whole before entering the storage stage, thereby reducing the risk of textural changes and water separation caused by structural relaxation, ion migration, or water redistribution during subsequent storage. As a result, long-term structural stability, good taste retention, and high levels of nutritional and color stability of the jam are achieved without exogenous sugars.

[0041] The present invention, by adopting the above technical solution, has the following beneficial effects: (1) By synergistically designing a compound system of low-methoxyamide pectin and seaweed dietary fiber under the condition of no exogenous sugar, and combining it with the ion cross-linking process involving calcium ions, a complex polysaccharide structure formed by the superposition of covalent cross-linking network and ion cross-linking network is constructed, so that the jam can still form a continuous, stable and water-holding gel system without relying on sucrose or sugar substitutes, thereby significantly reducing the risk of water separation during storage and maintaining good spreadability and taste stability.

[0042] (2) By dividing the enzymatic oxidation covalent crosslinking process into multiple stages and introducing the equivalent relationship of reaction intensity, the amount of laccase, reaction time and reaction temperature are synergistically constrained, so that the formation of pectin covalent crosslinking network is transformed from empirical control to quantitative control, ensuring that the crosslinking density and spatial distribution formed under different batches and different process fluctuations remain consistent, thus providing a uniform and reliable skeleton basis for subsequent ionic crosslinking and overall structural stability.

[0043] (3) By designing the degassing process into two stages, rapid oxygen reduction and stable oxygen control, and establishing a functional relationship between the control of residual dissolved oxygen and the system volume, temperature and degassing time, the system can obtain a repeatable low-oxygen environment before entering the enzymatic cross-linking reaction. This reduces the non-target consumption of dissolved oxygen on enzyme activity and avoids the deviation of the reaction path caused by fluctuations in oxygen conditions, thereby improving the controllability of the enzymatic cross-linking process and reducing the oxidative loss of active ingredients such as anthocyanins in the early stage of the reaction.

[0044] (4) By changing the introduction of calcium salt from one-time addition to multi-stage segmented addition and setting a static rearrangement process, and by coupling and limiting the amount of calcium salt, static time and system temperature, calcium ions participate in the ionic cross-linking reaction in the covalent cross-linking network in a controlled diffusion manner, reducing local excessive cross-linking and structural inhomogeneity, thereby significantly improving the uniformity, anti-shrinkage ability and long-term water retention stability of the composite polysaccharide network.

[0045] (5) By completing the construction of the polysaccharide network and introducing the anthocyanin stabilization system, and then implementing low-temperature ultra-high pressure treatment, sterilization is achieved without introducing heat effects, and the formed composite structure is locked as a whole. This allows the jam to maintain high nutritional activity and natural color while obtaining good microbial safety and structural stability during storage, thus achieving a synergistic unity of clean label, high nutrition and long-term stability. Detailed Implementation

[0046] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0047] Unless otherwise defined, all scientific and technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art.

[0048] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0049] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0050] The present invention will now be described in detail with reference to specific embodiments, which are intended to understand rather than limit the invention.

[0051] Unless otherwise specified, in the following examples, the beet-derived low-methoxylated pectin is GENU® Pectin LM-104 AS from CP Kelco, with a methoxylation degree of 28% and an amidation degree of 12%. The soluble dietary fiber from brown algae is food-grade brown algae dietary fiber from Qingdao Haizhiyuan Biotechnology Co., Ltd., and the galactomannan dietary fiber from red algae is κ-carrageenan (food grade) from Fujian Luxin Group. Calcium salts are calcium lactate. Rosemary extract is Duralox® Rosemary Extract from Kalsec, primarily composed of caryopsisic acid.

[0052] Example 1 This embodiment discloses a high-nutrition, additive-free confectionery jam based on seaweed dietary fiber and its preparation method. The jam described in this embodiment, by weight, consists of the following components: Fruit base: Blueberry pulp, 60.0 parts, with a natural soluble solids content of 11.2 °Brix; Low-methoxylated pectin from beets: 1.0 part Seaweed dietary fiber complex system: 3.0 parts in total, including 2.4 parts of soluble dietary fiber from brown algae and 0.6 parts of galactomannan dietary fiber from red algae.

[0053] Calcium salts: 0.12 parts; Anthocyanin stabilizing system: 0.16 parts in total, including: 0.08 parts ascorbic acid, 0.04 parts sodium citrate, and 0.04 parts rosemary extract. Deionized water: up to 100 parts.

[0054] The preparation method of this embodiment includes the following steps: S1: Fresh blueberry pulp was cryogenically crushed at 8°C and processed twice using a colloid mill to ensure uniform particle size. The pH of the pulp was then adjusted to 3.2 using a food-grade citric acid solution. After adjustment, the pulp was allowed to stand at 8°C for 10 minutes before use.

[0055] S2: At 18℃, slowly add the weighed soluble dietary fiber from brown algae and galactomannan dietary fiber from red algae into part of the deionized water, and stir at 300 rpm for 20 minutes to fully disperse and complete the initial hydration.

[0056] Subsequently, low-methoxyamide pectin from beets was added to the above system in two batches. The first batch consisted of 0.4 parts, and the mixture was stirred for 15 minutes to allow it to be initially wetted and dispersed. The second batch consisted of 0.6 parts, and the mixture was stirred for another 15 minutes to allow the pectin to fully swell and form a homogeneous polysaccharide continuous phase with the seaweed dietary fiber.

[0057] S3: Slowly add the polysaccharide system obtained in step S2 to the fruit pulp in step S1, and mix at 200 rpm for 15 minutes at 15°C to form a uniform jam matrix system.

[0058] S4: Dissolve calcium lactate in a small amount of deionized water to prepare a 5% (w / w) calcium salt solution. Add this solution to the system obtained in step S3 at 15°C and continue stirring at 200 rpm for 10 minutes to ensure that calcium ions are evenly distributed in the system and undergo ionic cross-linking with pectin.

[0059] S5: At 15℃, ascorbic acid, sodium citrate, and rosemary extract were added to the system sequentially according to the formula ratio. After each addition, the mixture was stirred for 5 minutes until all ingredients were added and thoroughly mixed. After the addition was complete, the dissolved oxygen content of the system was measured to be 1.2 mg / L, and the pH of the system was 3.25.

[0060] S6: The above jam system is aseptically filled and sealed at 12°C, and then placed in an ultra-high pressure equipment. The ultra-high pressure treatment is completed at 600MPa pressure and 15°C temperature for 4 minutes. After the treatment, the pressure is slowly released and cooled to room temperature to obtain the finished jam.

[0061] Example 2 The difference between this embodiment and embodiment 1 lies in the specific implementation of step S3, which is as follows: Food-grade laccase was added to the polysaccharide system obtained in step S2 at 15 ℃. The amount of laccase added was 0.035 parts (E), and the amount of beet-derived low-methoxyamidized pectin (G) in the system was 1.0 part. After the laccase was added and evenly dispersed, the following two consecutive stages of covalent cross-linking reaction were carried out sequentially: The first stage of covalent crosslinking reaction: the reaction was maintained at 14 ℃ (T1) for 20 minutes (τ1). The second stage of covalent crosslinking reaction: continue the reaction at 16 ℃ (T2) for 30 minutes (τ2).

[0062] The above parameters satisfy the following relationship: (E×(τ1+τ2)) / (G×((T1+T2) / 2))=0.117 Example 3 The difference between this embodiment and Embodiment 2 lies in the specific implementation method of the degassing stage in step S3. The degassing process is as follows: S3-a First stage degassing treatment: After completing step S2 in Example 2 and before adding food-grade laccase, the jam matrix system, which has been fully dispersed and hydrated by the seaweed dietary fiber compound system and the low-methoxyamidized pectin from beets, is placed at 15 ℃ and degassed in a vacuum manner for the first stage of degassing treatment.

[0063] The degassing time was controlled at 3 minutes, which reduced the dissolved oxygen content of the system from the initial value of about 6.0 mg / L to about 2.8 mg / L, corresponding to about 47% of the initial dissolved oxygen content.

[0064] S3-b Second-stage degassing treatment: After completing the first-stage degassing treatment, the system is subjected to a second-stage degassing treatment at 15 °C for 10 minutes, with a system volume of 20 L.

[0065] After the second stage of degassing, the dissolved oxygen (DO) content of the system was 0.06 mg / L.

[0066] The parameters for the second-stage degassing treatment were calculated and satisfy the following relationship: DO≤(0.08×T+0.015×t) / V=0.0675.

[0067] After completing the second stage of degassing, food-grade laccase was immediately added to the degassed jam matrix system at 15 °C, following the same procedure as in Example 2, and the two-stage covalent cross-linking reaction steps described in Example 2 were continued.

[0068] Example 4 The difference between this embodiment and embodiment 3 lies in the specific implementation of step S4, as follows: Step S4 will no longer involve adding calcium salt all at once, but will instead be implemented in the following three stages: S4-1 First stage of calcium addition and settling: After completing step S3 in Example 3, calcium lactate of the first stage is added to the jam system at 15 ℃, with an addition amount of 0.04 parts. After the addition is completed, the mixture is left to stand for 8 minutes without stirring, so that calcium ions can undergo initial diffusion and binding in the already formed pectin covalent cross-linked network.

[0069] S4-2 Second Stage Calcium Addition and Settling: After the first stage of settling is completed, calcium lactate of the second stage is added to the system at 15 ℃, with an addition amount of 0.04 parts. After the addition is completed, the system is also settling for 8 minutes under static conditions to allow calcium ions to further participate in the ionic cross-linking of pectin carboxyl sites and complete the rearrangement process inside the network.

[0070] S4-3 Third Stage Calcium Addition: After the second stage of settling is completed, calcium lactate of the third stage is added to the system at 15 ℃. The amount added is 0.04 parts. After adding, the mixture is slowly stirred for 5 minutes to replenish the remaining calcium ion sites that can participate in cross-linking and to complete the shaping of the overall ionic cross-linking structure.

[0071] In the above three stages, the total amount of calcium salt added (Ca) was 0.12 parts, the amount of pectin (G) was 1.0 parts, the cumulative settling time (Δt) between the two settling periods was 16 minutes, and the system temperature (T) was 15 ℃. The above parameters satisfy the following relationship: (Ca×Δt) / (G×T)=0.128.

[0072] After completing the third stage of calcium addition and mixing, the same subsequent process steps as in Example 3 are immediately followed, including the addition of the anthocyanin stabilizing system and the low-temperature ultra-high pressure treatment step.

[0073] Comparative Example 1 The difference between this comparative example and Example 1 is that the raw materials do not contain the seaweed dietary fiber compound system. The formula is adjusted as follows: Blueberry puree: 60 servings; Low-methoxylated pectin from beets: 1 part; Calcium lactate: 0.12 parts; Anthocyanin stabilizing system: 0.16 parts; Water: Make up to 100 servings.

[0074] The preparation method no longer includes the dispersion and hydration steps of seaweed dietary fiber; the remaining steps are the same as in Example 1.

[0075] Comparative Example 2 The difference between this comparative example and Example 1 is that the beet-derived low-methoxylated pectin used in Example 1 was replaced with non-amidated low-methoxylated pectin with a methoxylation degree of 30% and an amidation degree of 0%, and the amount used was 1 part. The pectin used was food-grade low-methoxylated pectin GENU® Pectin LM-102 produced by CP Kelco.

[0076] Comparative Example 3 The difference between this comparative example and Example 1 is that the raw materials do not contain calcium salts. The formulation is adjusted as follows: Blueberry puree: 60 servings; Low-methoxylated pectin from beets: 1 part; Seaweed dietary fiber compound system: 3 servings; Anthocyanin stabilizing system: 0.16 parts; Water: Make up to 100 servings.

[0077] The following performance tests were performed on the samples from Examples 1-4 and Comparative Examples 1-3.

[0078] (a) Gel structure and textural properties testing: The prepared jam samples were left to stand at 4 ℃ for 24 h to observe whether a continuous and stable gel structure was formed, and to record whether any layering, collapse, or obvious flow occurred. Subsequently, the samples were spread unidirectionally using a stainless steel spatula at 20 ℃. The spreadability and structural integrity of the jam were evaluated by observing whether any breakage, tailing, or obvious water separation occurred during the spreading process.

[0079] Furthermore, a simplified compression test was performed on the samples using a food texture analyzer. A cylindrical probe was selected, and the hardness value of the samples was measured under a 30% compression ratio to reflect the mechanical stability of the jam gel structure.

[0080] The test results are shown in Table 1 below.

[0081] Table 1 (II) Water separation rate test: The water separation rate of the jam samples was determined by centrifugation. 10 g of jam sample was weighed and placed in a centrifuge tube, and centrifuged at 3000 rpm for 10 min. After centrifugation, the mass of the separated free water was collected and weighed.

[0082] The water separation rate was calculated as the ratio of the mass of the separated water to the mass of the original sample, which was used to evaluate the jam system's ability to confine water under conditions without exogenous sugar.

[0083] The test results are shown in Table 2 below.

[0084] Table 2 (III) Water-holding stability test: The jam samples were sealed and stored at 4 ℃. Samples were taken on the 7th, 15th, and 30th days of storage to observe the appearance of the jam and record whether water separation occurred, in order to evaluate the long-term water-holding stability of the jam under refrigeration conditions. The test results are shown in Table 3 below.

[0085] Table 3 (iv) Anthocyanin content and retention rate detection: The total anthocyanin content in jam samples was determined using the pH difference method, with cyanidin-3-glucoside as the standard for conversion. The anthocyanin content in the filled jam samples was used as the initial value, and the anthocyanin content was measured after storage at 4 ℃ for 15 days and 30 days. The anthocyanin retention rate was calculated by comparing the results at different time points, thus evaluating the stability and protection effect of the jam on anthocyanins during non-thermal processing and storage. The test results are shown in Table 4 below.

[0086] Table 4 (v) Color stability test: The color parameters of the jam samples were measured using a colorimeter, and the L values ​​of the samples at different storage time points were recorded. a b The color value was calculated, and the total color difference ΔE was determined to characterize the degree of color change in the jam during storage. A smaller ΔE value indicates better color stability of the jam. The test results are shown in Table 5 below.

[0087] Table 5 (vi) Microbiological safety testing: In accordance with the GB 4789 series of national food safety standards, the total bacterial count, mold, and yeast counts of the jam samples after ultra-high pressure processing were tested to evaluate the microbiological safety of the product under non-heat sterilization conditions. The test results are shown in Table 6 below.

[0088] Table 6 The above performance test results show that, through the synergistic design of seaweed dietary fiber-low methoxyamide pectin composite system, controlled enzymatic covalent crosslinking, staged ionic crosslinking, and low-temperature ultra-high pressure non-thermal sterilization, this invention achieves a stable gel structure, significantly reduced water separation rate, excellent anthocyanin retention rate, and reliable microbial safety of the jam system without adding exogenous sugars or sugar substitutes.

[0089] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A high-nutrition, additive-free confectionery sauce based on seaweed dietary fiber, characterized in that, By weight, it includes the following components: 55-70 parts fruit base; 0.7–1.3 parts of low-methoxylated pectin from beets; 2.2–4.2 portions of seaweed dietary fiber compound system; 0.06–0.18 parts calcium salt; 0.08–0.25 parts anthocyanin stabilization system; The remainder is water. The jam contains no added exogenous sugars or artificial or natural sugar substitutes. The methoxylation degree of the sugar beet-derived low-methoxylated pectin is no higher than 35%, and the amidation degree is 5-20%. The seaweed dietary fiber compound system includes 1.6 to 3 parts of soluble dietary fiber from brown algae and 0.2 to 0.8 parts of galactomannan dietary fiber from red algae.

2. The high-nutrition, additive-free candy sauce based on seaweed dietary fiber according to claim 1, characterized in that, The fruit base is selected from one or more of blueberries, blackcurrants, mulberries, and raspberries, and the natural soluble solids content of the fruit base is 8–14 °Brix.

3. The high-nutrition, additive-free candy sauce based on seaweed dietary fiber according to claim 1, characterized in that, The calcium salt is selected from calcium lactate or calcium gluconate.

4. The high-nutrition, additive-free candy sauce based on seaweed dietary fiber according to claim 1, characterized in that, The anthocyanin stabilizing system consists of the following components in parts by weight: 0.03–0.12 parts ascorbic acid or isoascorbic acid; 0.01–0.05 parts sodium citrate; 0.005–0.03 parts rosemary extract, Furthermore, the ascorbic acid A, sodium citrate B, rosemary extract C, system pH, and dissolved oxygen (DO) satisfy the following relationship: 1 ≤ A / B ≤ 6 and 0.15 ≤ (A × C) / B ≤ 3.0 and (A × C) / (B × DO × pH) = 0.5~6.5; where A, B, and C are in parts by weight, and DO is in mg / L, thereby simultaneously constraining the pathways of free radical scavenging, metal ion complexation, and anthocyanin oxidation.

5. A method for preparing a high-nutrition, additive-free confectionery sauce based on seaweed dietary fiber as described in any one of claims 1 to 4, characterized in that, Includes the following steps: S1: Crush the fruit base material and make fruit pulp at a temperature not exceeding 10℃, and adjust the pH of the obtained fruit pulp to 2.9-3.6; S2: The seaweed dietary fiber compound system was dispersed and hydrated at 15-20℃, and then beet-derived low-methoxyamidized pectin was added to the resulting system in two separate portions. S3: Degas the system obtained in step S2 at 10–18°C, and after the degassing is completed, add the enzymatic oxidative crosslinking system at 12–18°C and react. S4: Add calcium salts to the system obtained in step S3 in a segmented manner to form an ionic cross-linked structure; S5: Add the anthocyanin stabilizing system to the system obtained in step S4 and mix thoroughly; S6: The system obtained in step S5 is filled and sealed under low temperature conditions, and then the sealed jam is subjected to ultra-high pressure treatment.

6. The method for preparing a high-nutrition, additive-free confectionery sauce based on seaweed dietary fiber according to claim 5, characterized in that, Step S3 includes the following stages: S3-1, add food-grade laccase at 12-18℃ and disperse and mix; S3-2 undergoes a first-stage covalent cross-linking reaction at 12–18°C. S3-3 undergoes a second-stage covalent crosslinking reaction at 12–18°C. Furthermore, the amount of laccase added (E), the amount of pectin used (G), the reaction time of the first stage (τ1), the reaction time of the second stage (τ2), the reaction temperature of the first stage (T1), and the reaction temperature of the second stage (T2) satisfy the following relationship: (E×(τ1+τ2)) / (G×((T1+T2) / 2)) = 0.008~0.12, E and G are expressed in parts by weight, τ1 and τ2 in minutes, and T1 and T2 in degrees Celsius.

7. The method for preparing a high-nutrition, additive-free confectionery sauce based on seaweed dietary fiber according to claim 5, characterized in that, Step S3 includes the following degassing stage: S3-a, the system obtained in step S2 is subjected to the first stage of degassing treatment, reducing the dissolved oxygen content of the system to 30% to 60% of the initial dissolved oxygen content within 1 to 5 minutes; S3-b, after completing the first stage of degassing, the system undergoes a second stage of degassing to stabilize and control the residual dissolved oxygen in the system. Furthermore, in the second stage of degassing, the dissolved oxygen content (DO), degassing time (t), system temperature (T), and system volume (V) satisfy the following relationship: DO ≤ (0.08×T + 0.015×t) / V, Where DO is expressed in mg / L, t in minutes, T in degrees Celsius, and V in liters.

8. The method for preparing a high-nutrition, additive-free confectionery sauce based on seaweed dietary fiber according to claim 5, characterized in that, Step S4 includes the following stages: S4-1, add the first stage calcium salt and let stand; S4-2, add the second stage calcium salt and let stand; S4-3, with the addition of the third-stage calcium salt; Furthermore, the total amount of calcium salt added (Ca), the amount of pectin (G), the standing time (Δt), and the system temperature (T) satisfy the following relationship: (Ca×Δt) / (G×T) = 0.06~0.45, Where Ca and G are expressed in parts by weight, Δt in minutes, and T in degrees Celsius.

9. The method for preparing a high-nutrition, additive-free confectionery sauce based on seaweed dietary fiber according to claim 5, characterized in that, In step S6, the ultra-high pressure treatment is performed at a pressure of 580–620 MPa, a temperature of 10–20°C, and a holding time of 2.5–5 minutes. The ultra-high pressure treatment is performed after steps S4 and S5.

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