Introduction
If you have ever spent an evening dealing with unexplained bloating, sluggish digestion, or that uncomfortable heaviness after a meal, you are not alone. Across the UK, millions of people regularly experience low-level digestive discomfort that leaves them searching supermarket aisles and health blogs for answers. In recent years, traditional fermented foods have stepped firmly into the wellness spotlight, with miso paste often praised as a gut-healing staple.
Originating in East Asia and deeply rooted in Japanese culinary culture, miso is far more than a savoury base for soup. It is a biologically active, fermented food packed with live microorganisms, bioactive peptides, and essential micronutrients. However, when navigating everyday digestive health, it can be difficult to separate genuine nutritional science from modern health trends.
This article explores what the clinical research says about miso and digestive function, how fermentation alters its nutritional profile, and how you can incorporate it safely into your routine. It is designed for anyone looking to support their digestion naturally while taking a balanced, evidence-based approach to overall wellness.
At Blue Horizon, we believe that dietary changes are a wonderful supporting tool, but they work best as part of a sensible, stepped journey. If you are struggling with persistent digestive or systemic symptoms, the first step is always a conversation with your GP to rule out underlying clinical causes. From there, simple lifestyle adjustments, structured symptom tracking, and targeted blood analysis can help you build a complete picture of your health.
What Is Miso and How Is It Made?
Miso is a traditional, thick seasoning paste created by fermenting cooked soybeans with salt and a starter culture known as koji. The koji starter is made by inoculating a grain—most commonly rice, barley, or soybeans themselves—with a beneficial fungal spore called Aspergillus oryzae.
The traditional production of miso follows a two-stage fermentation process that transforms simple ingredients into an ingredient rich in depth and flavour:
- Stage One (The Koji Starter): Grains such as steamed rice or barley are inoculated with Aspergillus oryzae. Over 40 to 48 hours, the mold produces an abundance of digestive enzymes, including amylases (which break down complex starches into simple sugars) and proteases (which break down dense proteins into amino acids).
- Stage Two (Secondary Fermentation): The enzyme-rich koji is thoroughly blended with cooked, mashed soybeans, water, and a specific ratio of sea salt. This mixture is packed tightly into vats to ferment. Over periods ranging from a few weeks to upwards of three years, beneficial yeasts and lactic acid bacteria flourish, maturing the paste and developing its distinct profile.
This biological transformation produces the five core taste profiles, most notably umami—a rich, savoury sensation driven by high concentrations of free glutamic acid released during protein breakdown.
Common Varieties of Miso
Miso is not a single, uniform ingredient. Different regions and production methods yield distinct varieties, generally identifiable by their colour, ingredients, and aging time:
- White Miso (Shiro Miso): Made with a higher proportion of rice koji and fermented for a shorter period (usually a few weeks to two months). It has a light golden hue, a delicate sweetness, and a milder, lower-salt flavour. It is an ideal starting point for dressings, light broths, and glazes.
- Yellow Miso (Shinshu Miso): Fermented slightly longer than white miso, usually with barley or rice. It offers a balanced, earthy flavour that works well across soups, marinades, and braises.
- Red Miso (Aka Miso): Made with a higher proportion of soybeans and aged for up to three years. The extended fermentation creates a deep reddish-brown colour, a robust aroma, and a pungent, salty flavour. It suits rich stews, dark sauces, and hearty root vegetable dishes.
- Barley Miso (Mugi Miso): Utilises barley koji combined with soybeans. It has a distinctive, rustic barley aroma with a savoury, slightly sweet profile.
Key Takeaway: The colour and flavour of miso reflect its fermentation length and ingredients. Lighter misos are sweeter and milder, while darker misos are aged longer, offering deeper flavour and higher concentrations of complex fermentation by-products.
Is Miso Good for Gut Health? The Science Explained
To understand whether miso is truly beneficial for your digestive tract, we must look at how its nutritional matrix interacts with human gastrointestinal physiology. Miso supports the digestive system through several distinct biological mechanisms. For broader practical advice, see this guide to improving gut and digestive health.
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| HOW MISO SUPPORTS THE GUT |
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| 1. Probiotic Strains -> Introduces friendly microbes to gut |
| 2. Enzyme Activity -> Pre-digests dense soy proteins |
| 3. Antinutrient Removal -> Reduces phytic acid for absorption |
| 4. Bioactive Peptides -> Supports intestinal barrier integrity |
| 5. Prebiotic Substrates -> Feeds beneficial resident bacteria |
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1. Delivery of Probiotic Microorganisms
The human large intestine houses trillions of microbes, collectively known as the gut microbiome. This intricate ecosystem plays an indispensable role in digesting dietary fibre, manufacturing essential vitamins, regulating immune responses, and protecting against pathogenic organisms.
Unpasteurised miso contains a living microbial community. During fermentation, Aspergillus oryzae works alongside various lactic acid bacteria (such as Tetragenococcus halophilus and Lactobacillus species) and salt-tolerant yeasts.
When you consume unpasteurised miso, these beneficial microbes pass into the digestive tract. While not all food-borne bacteria permanently colonise the colon, their transient passage provides valuable support:
- They produce lactic acid and short-chain organic acids that help maintain an optimal, slightly acidic pH in the gut lumen.
- An acidic environment discourages the overgrowth of opportunist, pathogenic bacteria.
- They interact with gut-associated lymphoid tissue (GALT), helping to modulate normal immune responses.
2. Breakdown of Antinutrients and Enhanced Digestibility
Whole legumes, including soybeans, are naturally dense in complex carbohydrates (oligosaccharides such as raffinose and stachyose) and storage compounds like phytic acid (phytates). In unfermented forms, these compounds can present digestive challenges:
- Oligosaccharides cannot be broken down by human stomach enzymes. When they reach the large bowel intact, resident bacteria rapidly ferment them, producing hydrogen and methane gas that leads to bloating, cramping, and wind.
- Phytic acid acts as an "antinutrient," binding tightly to essential dietary minerals such as iron, zinc, calcium, and magnesium in the digestive tract, which impairs their absorption into the bloodstream.
Fermentation serves as a form of external pre-digestion. The enzymes released by Aspergillus oryzae actively degrade phytic acid and dismantle troublesome oligosaccharides. This means the proteins and minerals in miso are far easier for the human digestive tract to break down and absorb, significantly reducing the likelihood of post-meal gas and discomfort compared to unfermented soy products.
3. Production of Bioactive Peptides and Short-Chain Fatty Acids
As the enzymes in koji break down soy proteins, they release small chains of amino acids known as bioactive peptides. Research indicates that these peptides possess notable antioxidant and mild anti-inflammatory properties within the gut mucosa.
Furthermore, the non-digestible fibres and starches present in miso act as prebiotics—fuel for your resident colonic bacteria. When your native microbiome ferments these prebiotic substrates, it produces short-chain fatty acids (SCFAs), predominantly acetate, propionate, and butyrate.
Butyrate is the primary energy source for the epithelial cells lining the colon (colonocytes). Adequate butyrate production helps maintain the structural integrity of the gut barrier, preventing unwanted compounds from crossing into systemic circulation and supporting a calm, resilient digestive environment.
4. Supporting Upper Digestive Comfort
Observational studies from Japan have explored the association between regular miso consumption and upper gastrointestinal comfort. Large population surveys suggest that individuals who regularly consume moderate amounts of traditional miso soup report lower rates of functional dyspepsia (indigestion) and acid reflux symptoms compared to those who do not.
While observational associations do not prove direct causation, researchers hypothesise that the combination of soothing warm liquid, easily absorbed amino acids, and digestive enzymes helps support comfortable gastric emptying and stomach acid balance.
Key Takeaway: Miso supports gut health not just through live probiotic bacteria, but by neutralising plant antinutrients, easing protein breakdown, and supplying prebiotics that nourish your gut lining.
Beyond the Gut: Broader Nutritional and Health Potential
While gut support is the primary reason many people turn to miso, this fermented paste offers a broad spectrum of nutritional benefits that extend to wider metabolic and systemic health. Blue Horizon’s nutritional blood testing collection includes options relating to vitamins, minerals, iron status, and broader nutritional markers.
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| MISO NUTRITIONAL HIGHLIGHTS |
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| * Complete Plant Protein (All 9 essential amino acids) |
| * Rich in Isoflavones (Daidzein and Genistein) |
| * Micronutrients: Vitamin K, Manganese, Zinc, Copper |
| * Fermentation By-products: Microbial B-vitamins |
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Complete Plant-Based Protein
Soybeans are one of the few plant sources that provide a complete amino acid profile, meaning they contain all nine essential amino acids that the human body cannot synthesise on its own. A single tablespoon of miso paste (roughly 15 to 17 grams) delivers approximately 2 to 3 grams of easily digestible plant protein, making it an excellent flavourful booster for plant-based and omnivorous diets alike.
Antioxidant and Isoflavone Activity
Miso contains natural polyphenols and soy isoflavones, primarily genistein and daidzein. During fermentation, microbial enzymes convert these isoflavones into their "aglycone" forms—unbound molecules that are smaller and significantly easier for the human gut to absorb.
Isoflavones and other antioxidant compounds in miso help neutralise free radicals, unstable molecules that contribute to oxidative stress and cellular wear-and-tear throughout the body. Furthermore, because isoflavones are phytoestrogens (plant compounds that weakly bind to human oestrogen receptors), research has explored their potential role in gently supporting hormonal balance and easing mild vasomotor symptoms, such as hot flushes, during the perimenopause and menopause.
Micronutrient Density
Despite being consumed in relatively small culinary amounts, miso provides a meaningful contribution of micronutrients:
- Vitamin K: Important for normal blood clotting mechanisms and bone matrix mineralisation.
- Manganese and Copper: Essential trace minerals that serve as cofactors for antioxidant enzymes (such as superoxide dismutase) and support connective tissue maintenance.
- Zinc: An essential mineral vital for immune function, mucosal healing, and digestive enzyme synthesis.
- B-Complex Vitamins: Lactic acid bacteria and yeasts synthesise small amounts of B vitamins during the fermentation process, contributing to cellular energy pathways.
Practical Considerations: Preparing, Cooking, and Selecting Miso
To gain the maximum digestive benefit from miso, how you shop for and prepare it matters substantially. Not all miso products on supermarket shelves offer the same biological activity.
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| HOW TO PRESERVE LIVE MISO PROBIOTICS |
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| 1. Purchase raw, unpasteurised tubs from the chiller. |
| 2. Cook your soup vegetables, noodles, and broth first. |
| 3. Remove the pan from the heat; let it cool slightly. |
| 4. Whisk miso paste with warm broth in a small ladle. |
| 5. Stir the smooth mixture back in without boiling. |
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Choosing the Right Tub
When shopping in UK supermarkets, health food shops, or East Asian grocers, keep these tips in mind:
- Look for "Unpasteurised" or "Live": Commercial pasteurisation involves heat-treating the paste to extend shelf life and prevent the tub from swelling with fermentation gases. However, intense heat kills the beneficial probiotic bacteria and deactivates fragile enzymes. To get live cultures, look for tubs marked "unpasteurised" or "raw," usually found in the refrigerated section.
- Check the Ingredient List: Authentic miso requires very few ingredients: soybeans, a grain (koji), water, and salt. Avoid products loaded with artificial preservatives, excessive added sugars, flavour enhancers, or monosodium glutamate (MSG) blends, which are often used to mask rushed fermentation times.
- Storage: Keep opened miso in an airtight container in the fridge. Because of its natural salt content and fermentation stability, unpasteurised miso can safely keep for many months without spoiling, though its flavour and colour will naturally deepen over time.
The "Never-Boil" Golden Rule
The most common culinary mistake with miso is boiling it vigorously in soup stock. Exposing live miso paste to boiling temperatures (100°C) immediately destroys its delicate live bacteria and denatures its active enzymes.
To preserve its probiotic potential:
- Prepare your soup base, vegetables, and proteins completely.
- Take the saucepan off the heat and allow the liquid to stop bubbling and cool slightly (ideally below 60°C).
- Ladle a small amount of the warm broth into a small bowl or measuring jug, add your tablespoon of miso paste, and whisk until completely smooth.
- Gently stir the dissolved miso back into the warm pan just before serving.
Simple Ways to Incorporate Miso
You do not need to limit miso to traditional Japanese soups. Its versatile umami depth works across many dishes:
- Salad Dressings: Whisk a teaspoon of white miso with extra virgin olive oil, apple cider vinegar, a touch of grated ginger, and a drop of honey for an enzyme-rich dressing.
- Roasted Root Vegetables: Brush a glaze of yellow miso, warm water, and a touch of sesame oil over carrots, parsnips, or aubergine before roasting.
- Comforting Broths: Stir a spoonful of live red miso into warm bone broth or vegetable stock for a mid-afternoon restorative drink.
- Marinades: Combine miso with garlic and citrus juice to marinate salmon, tofu, or chicken breasts before gentle grilling.
Important Cautions and Who Should Be Careful
While miso is a wholesome, nutrient-dense food for the majority of people, it is not suitable for every dietary circumstance. Responsible health management means understanding potential contraindications.
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| WHO SHOULD EXERCISE CAUTION |
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| * Low-Sodium Diets -> High natural salt content |
| * Thyroid Medication -> Soy can impair levothyroxine uptake |
| * Coeliac Disease -> Some varieties use barley koji |
| * MAOI Medications -> Fermented foods contain tyramine |
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1. High Sodium Content and Blood Pressure
Miso relies on salt to control the fermentation environment and prevent harmful putrefactive bacteria from multiplying. A single tablespoon (approximately 15g) can contain between 1.0g and 1.5g of salt, which represents a notable portion of the UK NHS recommended maximum daily intake of 6g for adults.
Interestingly, animal studies and some human observational data suggest that the sodium in fermented miso does not elevate blood pressure or strain the cardiovascular system to the same degree as pure table salt (sodium chloride), likely due to the balancing effects of soy peptides and potassium.
However, if your GP has placed you on a strict low-sodium diet due to hypertension, chronic kidney disease, or heart failure, you should account for miso in your daily salt allowance and consult your GP or a registered dietitian before increasing your intake.
2. Thyroid Health and Medication Interference
Soybeans contain natural compounds known as goitrogens (specifically isoflavones), which have the potential to interfere with how the thyroid gland utilises iodine to produce thyroid hormones.
For people with normal thyroid function who consume adequate dietary iodine (from seafood, dairy, or fortified foods), moderate miso intake is generally completely safe. However, if you are diagnosed with hypothyroidism or take levothyroxine, timing is critical.
Soy protein can bind to levothyroxine in the gut and significantly reduce its absorption into your bloodstream. As a general rule:
- Always take your thyroid medication on an empty stomach with a glass of water first thing in the morning.
- Wait at least 30 to 60 minutes before eating breakfast.
- Ensure that any concentrated soy products, including miso, are consumed several hours away from your medication window (ideally at lunch or dinner).
- Never adjust your prescribed thyroid medication dosage based on dietary changes without explicit guidance from your GP or endocrinologist.
3. Coeliac Disease and Gluten Considerations
Pure soybean miso and rice-based miso (Kome Miso) are naturally gluten-free. However, barley miso (Mugi Miso) is made using barley koji, which contains gluten. Furthermore, cross-contamination can occur during manufacturing. If you have coeliac disease or non-coeliac gluten sensitivity, always check packaging labels carefully to verify that the product is certified gluten-free.
When Gut Symptoms Persist: The Blue Horizon Method
Adding a nourishing, live food like miso to your diet can be a wonderful way to support your daily digestive processes. However, nutritional tweaks are not a cure-all. If you are regularly troubled by persistent gut symptoms—such as stubborn bloating, sudden alterations in bowel habits, chronic fatigue, acid reflux, or unexplained discomfort—it is essential to approach your health methodically rather than relying on guesswork.
At Blue Horizon, we champion a phased, clinically responsible journey:
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| THE BLUE HORIZON METHOD |
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| STEP 1: Primary Care Review (GP First) |
| Rule out red-flag gastrointestinal pathologies. |
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| STEP 2: Structured Self-Tracking |
| Log symptoms, meal timing, sleep, stress, and stool. |
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| STEP 3: Targeted Blood Profiling |
| Assess systemic cofactors (Thyroid, Iron, B12, hs-CRP). |
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Step 1: Consult Your GP First
Dietary changes should never replace standard medical evaluation. Your first port of call must be your NHS GP practice. Your doctor can perform routine clinical examinations and rule out serious conditions that require targeted medical intervention, such as:
- Inflammatory Bowel Disease (Crohn's disease or Ulcerative Colitis)
- Coeliac disease (via NHS serological blood tests, completed while still eating gluten)
- Bowel infections or structural abnormalities
- Significant anaemia or overt thyroid disorders
Always seek prompt GP advice if you notice "red flag" symptoms, such as unexplained weight loss, blood in your stool, persistent changes in bowel habits lasting more than three weeks, or difficulty swallowing.
Step 2: Structured Self-Tracking
If your GP has ruled out acute pathology but you still do not feel your best, start keeping a structured daily health diary. Rather than restricting foods haphazardly, spend two to three weeks noting:
- Dietary Intake: What you eat, including fermented foods like miso, and the rough times of your meals.
- Symptom Timing: When bloating, gas, or sluggishness occurs (e.g., 30 minutes post-meal vs. late evening).
- Lifestyle Markers: Daily water intake, sleep duration and quality, and subjective stress levels.
- Bowel Patterns: Frequency and consistency using the Bristol Stool Chart.
For more ideas on structured monitoring, this guide to gut health and microbiome signs explores symptom timing, bowel patterns, and broader digestive factors.
Often, patterns emerge that reveal how stress, rushed meals, poor hydration, or specific ingredients influence your digestion.
Step 3: Targeted Blood Testing as an Informative Snapshot
If you have completed standard checks with your GP, improved your lifestyle, and are still experiencing low energy, persistent sluggishness, or digestive irregularities, looking deeper at systemic biology can provide valuable clarity.
Gastrointestinal symptoms do not exist in isolation. Many physiological systems directly influence how your gut moves, absorbs nutrients, and maintains its mucosal lining. A private blood test provides a detailed biochemical snapshot, helping you and your healthcare professional explore underlying imbalances that might be contributing to how you feel.
Understanding the Bigger Picture: Thyroid and Metabolic Links to Gut Health
When people struggle with unexplained digestive issues—particularly chronic constipation, bloating, and post-meal sluggishness—they often look exclusively at the stomach and intestines. However, your metabolism and hormonal network play a profound role in digestive performance.
How the Thyroid Governs Digestion
Your thyroid gland acts as the master regulator of your metabolic rate. Thyroid hormones—specifically Free Thyroxine (T4) and the biologically active Free Triiodothyronine (T3)—directly control the speed of the gastrointestinal tract (gut motility):
- Thyroid Underactivity (Hypothyroidism): When thyroid hormone output drops, intestinal peristalsis (the muscular contractions that move food along) slows down significantly. This can lead to chronic constipation, abdominal distension, reduced production of stomach acid, and bacterial stagnation in the small intestine.
- Thyroid Overactivity (Hyperthyroidism): Excess thyroid hormones accelerate motility, often leading to loose stools, frequent bowel movements, and nutrient malabsorption.
If you are eating fermented foods like miso, drinking water, and eating plenty of fibre but still struggle with persistent constipation, cold intolerance, low mood, and profound fatigue, assessing your thyroid function is a sensible clinical consideration. You can compare available options in the thyroid blood testing collection.
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| BLUE HORIZON TIERED THYROID TESTING |
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| BRONZE | TSH + Free T4 + Free T3 |
| | + Extras: Magnesium & Cortisol |
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| SILVER | Everything in Bronze |
| | + Autoimmune Antibodies: TPOAb & TgAb |
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| GOLD | Everything in Silver |
| | + Vital Nutrients: Ferritin, Folate, B12, Vit D, CRP |
| |
| PLATINUM | Everything in Gold |
| | + Full Iron Panel, HbA1c, Reverse T3 (Venous only) |
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The Blue Horizon Thyroid Testing Range
Standard NHS testing frequently evaluates Thyroid Stimulating Hormone (TSH) as a frontline screening tool, and only cascades to Free T4 if TSH falls outside the reference range. While this is practical for initial screening, looking at a comprehensive hormone panel offers a far more detailed overview.
At Blue Horizon, our tiered thyroid testing range is designed to provide clear, structured options depending on how deep you wish to look:
- Bronze Tier: Measures core thyroid hormones (TSH, Free T4, and Free T3) to assess production and conversion, along with our unique Blue Horizon Extras: Magnesium and Cortisol. Most private providers do not include these cofactors, yet magnesium is essential for cellular enzyme function and cortisol (the primary adrenal stress hormone) directly influences thyroid hormone conversion. The Thyroid Premium Bronze profile provides the full test details.
- Silver Tier: Contains everything in the Bronze tier, while adding Thyroid Peroxidase Antibodies (TPOAb) and Thyroglobulin Antibodies (TgAb). These markers check for autoimmune thyroid activity (such as Hashimoto's thyroiditis), which can cause fluctuating digestive and metabolic symptoms long before baseline TSH fails.
- Gold Tier: Builds upon the Silver tier by incorporating vital nutritional cofactors: Ferritin (stored iron), Folate, Active Vitamin B12, Vitamin D (25-OH), and C-Reactive Protein (CRP) (a marker of systemic inflammation). Because a sluggish gut can impair the absorption of these exact vitamins, this tier offers a broader, holistic snapshot of systemic wellness.
- Platinum Tier: Our most comprehensive metabolic and thyroid profile. It includes everything in Gold, plus Reverse T3, HbA1c (long-term blood sugar regulation), and an extended Iron Panel (Iron, Transferrin Saturation, TIBC, and UIBC). The Thyroid Premium Platinum profile contains the complete marker list and collection requirements.
Practical Details: Sample Collection and Timing
We strive to make pathology testing accessible and stress-free:
- Collection Methods: Bronze, Silver, and Gold tiers can be completed conveniently at home using a fingerprick (microtainer) blood kit or a modern Tasso sample device. Alternatively, you can book a professional phlebotomy blood draw at a partner clinic or arrange a nurse home visit.
- Platinum Requirements: Because the Platinum panel requires a larger volume of blood for its extensive marker suite, it requires a professional venous blood draw via a clinic visit or nurse home visit.
- Sample Timing: We recommend collecting your blood sample at around 9:00 am. Thyroid hormone secretion and cortisol levels follow a natural circadian rhythm, peaking in the early morning. Collecting at 9:00 am provides optimal consistency, especially if you plan to track your markers over time.
Important Note on Results: Blood testing provides a clear biochemical snapshot to guide your health journey; it does not replace a clinical diagnosis. Always review your laboratory results with your GP or a qualified specialist before making significant changes to medication, supplementation, or treatment plans. You can view current pricing and test options in the thyroid blood tests collection.
Summary: Making Miso Work for You
Miso is a versatile, nutrient-dense ingredient that can serve as a valuable addition to a gut-friendly lifestyle. Its unique combination of live probiotic bacteria, pre-digested proteins, reduced antinutrients, and prebiotic fibres provides gentle, ongoing support for everyday digestive comfort.
To get the most out of miso:
- Choose raw, unpasteurised tubs kept in the fridge to ensure you are receiving live, active cultures.
- Never boil your miso paste; stir it in at the very end of cooking to protect heat-sensitive microorganisms and enzymes.
- Be mindful of your overall sodium intake, and account for miso within a balanced, whole-food diet.
- If you take thyroid medication, leave several hours between your dose and consuming concentrated soy foods like miso.
- Follow a stepped, responsible health approach: see your GP first for persistent symptoms, track your lifestyle factors, and use targeted blood profiling if you need a deeper look at the underlying systems supporting your wellbeing.
FAQ
Does cooking miso paste kill its gut-friendly bacteria?
Yes, high heat destroys the live probiotic microorganisms and denatures the active enzymes found in unpasteurised miso. To preserve its digestive benefits, prepare your soup or dish first, remove the pan from the heat source, allow it to cool slightly (ideally below 60°C), and whisk in the miso paste just before serving.
How much miso should I consume daily for digestive benefits?
For most healthy adults, consuming one to two teaspoons (or up to one tablespoon, roughly 15g) per day provides a meaningful amount of beneficial microbes and enzymes without contributing excessive sodium. Incorporating it a few times a week as part of a varied diet containing other fermented foods is an excellent strategy.
Is miso safe for people with thyroid conditions?
Miso contains soy isoflavones, which can act as mild goitrogens and may interfere with thyroid hormone uptake if consumed in large quantities alongside an iodine deficiency. However, moderate culinary intake is generally considered safe. If you take levothyroxine, ensure you take your medication on an empty stomach and wait several hours before eating miso, as soy can inhibit medication absorption. Always discuss dietary adjustments with your GP.
What is the difference between pasteurised and unpasteurised miso?
Pasteurised miso has undergone heat treatment during packaging to extend its ambient shelf life and stop the fermentation process. While it retains its rich flavour, the heat kills the living probiotic bacteria and deactivates enzymes. Unpasteurised miso remains biologically active, containing live cultures and enzymes, and must be stored in the refrigerator.
